JP7573438B2 - Imaging device - Google Patents

Description

The present disclosure relates to an imaging device, and in particular to an imaging device that realizes a compact and low-profile device configuration and enables imaging while suppressing the occurrence of flare and ghosting.

In recent years, solid-state imaging elements used in camera-equipped mobile terminal devices, digital still cameras, and the like have become increasingly compact, high-resolution, and low-profile.

As cameras become more compact and have higher pixel counts, the lens and solid-state image sensor are closer on the optical axis, and it is becoming common for infrared light blocking filters to be placed near the lens.

For example, a technology has been proposed that enables the miniaturization of solid-state imaging elements by constructing the lowest layer lens of a lens group consisting of multiple lenses on the solid-state imaging element.

JP 2015-061193 A

However, if the lowest layer lens is constructed on the solid-state imaging element, although this contributes to making the device more compact and thinner, the distance between the infrared light cut filter and the lens becomes shorter, resulting in flare and ghosting caused by internal reflection of light.

This disclosure has been made in light of these circumstances, and in particular aims to achieve a compact, low-profile solid-state imaging element while suppressing the occurrence of flare and ghosting.

An imaging device according to one aspect of the present disclosure includes a solid-state imaging element that generates pixel signals by photoelectric conversion in response to an amount of incident light, and a lens group consisting of a plurality of lenses that focus the incident light on a light receiving surface of the solid-state imaging element, wherein a lowest layer lens that constitutes a lowest layer in a direction in which the incident light is incident among the lens group is configured at the forefront in a direction in which the incident light is received, the lowest layer lens is an aspheric concave lens, and an effective area for focusing the incident light on the solid-state imaging element is set, an anti-reflection film is formed on at least a surface of the effective area of the lowest layer lens, the effective area is disposed approximately at the center of a width of the lowest layer lens in a direction perpendicular to the incident light, and the effective area is provided with a reflective coating. A non-effective area is set in which incident light is not necessarily focused onto the solid-state imaging element, and the anti-reflection film is further provided on a bank-shaped protrusion with a flat portion formed in the non-effective area and having a thickness from the glass substrate described below that is thicker than the thickest thickness of the effective area of the lowest layer lens, on the side of the lowest layer lens, and on a glass substrate provided on the solid-state imaging element to which the lowest layer lens is attached, and on the side of the lowest layer lens, an area in which the anti-reflection film is not formed is provided in an area from a position a predetermined width closer to the glass substrate as viewed from the flat portion of the protrusion to a position a predetermined width closer to the flat portion as viewed from a position near the boundary between the lowest layer lens and the glass substrate.

In one aspect of the present disclosure, a solid-state imaging element generates a pixel signal by photoelectric conversion according to the amount of incident light, the incident light is focused on a light receiving surface of the solid-state imaging element by a lens group consisting of a plurality of lenses, the incident light is focused on a light receiving surface of the solid-state imaging element by a lens group having a lowest layer lens constituting a lowest layer with respect to an incident direction of the incident light, the lowest layer lens being configured in the forefront with respect to a direction in which the incident light is received, the lowest layer lens being an aspheric concave lens, an effective area is set for focusing the incident light on the solid-state imaging element, an anti-reflection film is formed on at least a surface of the effective area of the lowest layer lens, the effective area is disposed approximately in the center with respect to a width of the lowest layer lens in a vertical direction with respect to the incident light, and the effective area is provided with a reflective coating. A non-effective area is set in which incident light is not necessarily focused onto the solid-state imaging element, and the anti-reflection film is further provided on a bank-shaped protrusion with a flat portion formed in the non-effective area and having a thickness from the glass substrate described below that is thicker than the thickest thickness of the effective area of the lowest layer lens, on the side of the lowest layer lens, and on a glass substrate provided on the solid-state imaging element to which the lowest layer lens is attached, and on the side of the lowest layer lens, an area in which the anti-reflection film is not formed is provided in an area from a position a predetermined width closer to the glass substrate as viewed from the flat portion of the protrusion to a position a predetermined width closer to the flat portion as viewed from a position near the boundary between the lowest layer lens and the glass substrate.

According to one aspect of the present disclosure, particularly in solid-state imaging elements, it is possible to achieve a compact and low-profile device configuration while suppressing the occurrence of flare and ghosting.

1 is a diagram illustrating a configuration example of a first embodiment of an imaging device according to the present disclosure. 2 is a schematic external view of an integrated component including a solid-state imaging element in the imaging device of FIG. 1 . 11A and 11B are diagrams illustrating a substrate configuration of an integrated component portion. FIG. 2 is a diagram illustrating an example of a circuit configuration of a laminated substrate. FIG. 2 is a diagram showing an equivalent circuit of a pixel. FIG. 2 is a diagram showing a detailed structure of a laminated substrate. 2 is a diagram for explaining that ghosts and flares caused by internal reflection do not occur in the imaging device of FIG. 1 . 2 is a diagram for explaining that ghosts and flares caused by internal reflection do not occur in an image captured by the imaging device of FIG. 1 . FIG. 13 is a diagram illustrating a configuration example of a second embodiment of an imaging device according to the present disclosure. 10A and 10B are diagrams for explaining how ghosts and flares caused by internal reflection do not occur in the imaging device of FIG. 9 . FIG. 13 is a diagram illustrating a configuration example of a third embodiment of an imaging device according to the present disclosure. FIG. 13 is a diagram illustrating a configuration example of an imaging device according to a fourth embodiment of the present disclosure. FIG. 13 is a diagram illustrating a configuration example of an imaging device according to a fifth embodiment of the present disclosure. FIG. 13 is a diagram illustrating an example configuration of an imaging device according to a sixth embodiment of the present disclosure. FIG. 13 is a diagram illustrating a configuration example of an imaging device according to a seventh embodiment of the present disclosure. FIG. 13 is a diagram illustrating an example configuration of an imaging device according to an eighth embodiment of the present disclosure. FIG. 13 is a diagram illustrating a configuration example of a ninth embodiment of an imaging device according to the present disclosure. FIG. 23 is a diagram illustrating a configuration example of an imaging device according to a tenth embodiment of the present disclosure. FIG. 23 is a diagram illustrating a configuration example of an imaging device according to an eleventh embodiment of the present disclosure. FIG. 23 is a diagram illustrating a configuration example of an imaging device according to a twelfth embodiment of the present disclosure. FIG. 23 is a diagram illustrating a configuration example of a thirteenth embodiment of an imaging device according to the present disclosure. FIG. 26 is a diagram illustrating a configuration example of an imaging device according to a fourteenth embodiment of the present disclosure. FIG. 23 is a diagram illustrating a configuration example of an imaging device according to a fifteenth embodiment of the present disclosure. 24A to 24C are diagrams illustrating modified examples of the outer shape of the lens in FIG. 23. 24A to 24C are diagrams illustrating a modified example of the structure of the lens end portion of FIG. 23. 24A to 24C are diagrams illustrating a modified example of the structure of the lens end portion of FIG. 23. 24A to 24C are diagrams illustrating a modified example of the structure of the lens end portion of FIG. 23. 24A to 24C are diagrams illustrating a modified example of the structure of the lens end portion of FIG. 23. FIG. 23 is a diagram illustrating a configuration example of an imaging device according to a sixteenth embodiment of the present disclosure. 30A to 30C are diagrams illustrating a method for manufacturing the imaging device of FIG. 29. 30 is a diagram for explaining a modified example of the individualized cross section of the configuration example of FIG. 29 . 32 is a diagram for explaining a manufacturing method of the imaging device shown in the upper left of FIG. 31 . 32 is a diagram for explaining a manufacturing method of the imaging device shown in the lower left of FIG. 31 . 32A to 32C are diagrams illustrating a manufacturing method for the imaging device shown in the upper right of FIG. 31 . 32 is a diagram illustrating a manufacturing method of the imaging device shown in the lower right of FIG. 31 . FIG. 30 is a diagram illustrating a modified example in which an anti-reflection film is added to the configuration of FIG. 29. FIG. 30 is a diagram illustrating a modified example in which an anti-reflection film is added to the side surface of the configuration in FIG. 29. FIG. 23 is a diagram illustrating a configuration example of a seventeenth embodiment of an imaging device according to the present disclosure. 1A and 1B are diagrams for explaining the conditions for the thickness of a lens that is small, lightweight, and capable of capturing high-resolution images. 1A and 1B are diagrams for explaining the stress distribution applied to the AR coating on the lens when a mounting reflow thermal load is applied according to the shape of the lens. 40A and 40B are diagrams illustrating modified examples of the lens shape in FIG. 39. 42 is a diagram for explaining the shape of the two-stage side lens in FIG. 41. 42A to 42D are diagrams illustrating modified shapes of the two-stage side lens of FIG. 41. 42 is a diagram for explaining the stress distribution on the AR coating on the lens when the two-stage side type lens of FIG. 41 is subjected to a mounting reflow thermal load. 45 is a diagram for explaining the maximum value of the stress distribution applied to the AR coating on the lens when the mounting reflow heat load in FIG. 44 is applied. 26A to 26C are diagrams illustrating a manufacturing method of the imaging device according to the eighteenth embodiment of the present disclosure. 47A to 47C are diagrams illustrating a modified example of the manufacturing method of FIG. 46. 1A to 1C are diagrams illustrating a method for manufacturing a two-stage side lens. 11A to 11C are diagrams illustrating a modified example of the manufacturing method for a two-stage side lens. 50A to 50C are diagrams explaining adjustment of the angle between the average surfaces of the side surfaces, adjustment of surface roughness, and provision of a skirting portion in the manufacturing method of the two-stage side lens of FIG. 49. FIG. 23 is a diagram illustrating a configuration example of a nineteenth embodiment of an imaging device according to the present disclosure. 52 is a diagram for explaining an example of the alignment mark in FIG. 51. 52 is a diagram for explaining an application example using the alignment mark of FIG. 51. FIG. 23 is a diagram illustrating a configuration example of an imaging device according to a twentieth embodiment of the present disclosure. 1A and 1B are diagrams illustrating the stress distribution on the AR coating when a thermal load is applied to the AR coating during mounting and reflow in a case where the AR coating is formed on the entire surface and in a case where the AR coating is not formed on the entire surface. FIG. 23 is a diagram illustrating a configuration example of a twenty-first embodiment of an imaging device according to the present disclosure. 13A and 13B are diagrams illustrating an example in which a light-shielding film is formed on the side surface by connecting a lens and a bank. 1 is a block diagram showing an example of the configuration of an imaging device as an electronic device to which a camera module according to the present disclosure is applied. 1A to 1C are diagrams illustrating an example of use of a camera module to which the technology of the present disclosure is applied. 1 is a diagram illustrating an example of a schematic configuration of an endoscopic surgery system. 2 is a block diagram showing an example of the functional configuration of a camera head and a CCU. FIG. 1 is a block diagram showing an example of a schematic configuration of a vehicle control system; 4 is an explanatory diagram showing an example of the installation positions of an outside-vehicle information detection unit and an imaging unit; FIG.

A preferred embodiment of the present disclosure will be described in detail below with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configuration are designated by the same reference numerals to avoid redundant description.

Hereinafter, modes for carrying out the present disclosure (hereinafter, referred to as embodiments) will be described in the following order.
1. First embodiment 2. Second embodiment 3. Third embodiment 4. Fourth embodiment 5. Fifth embodiment 6. Sixth embodiment 7. Seventh embodiment 8. Eighth embodiment 9. Ninth embodiment 10. Tenth embodiment 11. Eleventh embodiment 12. Twelfth embodiment 13. Thirteenth embodiment 14. Fourteenth embodiment 15. Fifteenth embodiment 16. Sixteenth embodiment 17. Seventeenth embodiment 18. Eighteenth embodiment 19. Nineteenth embodiment 20. Twentieth embodiment 21. Twenty-first embodiment 22. Application example to electronic device 23. Use example of solid-state imaging device 24. Application example to endoscopic surgery system 25. Application example to moving body

1. First embodiment
<Configuration example of imaging device>
An example of the configuration of an image pickup device according to a first embodiment of the present disclosure, which suppresses the occurrence of ghosts and flares while realizing a compact and low-profile device configuration, will be described with reference to Fig. 1. Fig. 1 is a side cross-sectional view of the image pickup device.

The imaging device 1 in Figure 1 is composed of a solid-state imaging element 11, a glass substrate 12, an IRCF (infrared cut filter) 14, a lens group 16, a circuit board 17, an actuator 18, a connector 19, and a spacer 20.

The solid-state imaging element 11 is an image sensor consisting of a so-called CMOS (Complementary Metal Oxide Semiconductor) or CCD (Charge Coupled Device), and is fixed in an electrically connected state on the circuit board 17. As described later with reference to FIG. 4, the solid-state imaging element 11 is composed of a plurality of pixels arranged in an array, and generates a pixel signal according to the amount of incident light that is focused and incident on each pixel from the upper side in the figure through a lens group 16, and outputs the pixel signal as an image signal to the outside from a connector 19 via the circuit board 17.

A glass substrate 12 is provided on the upper surface of the solid-state imaging element 11 in Figure 1, and is attached to the upper surface with a transparent adhesive (GLUE) 13, i.e., an adhesive having approximately the same refractive index as the glass substrate 12.

The upper surface of the glass substrate 12 in FIG. 1 is provided with an IRCF 14 that cuts infrared light from the incident light, and is attached with a transparent adhesive (GLUE) 15 that has approximately the same refractive index as the glass substrate 12. The IRCF 14 is made of, for example, soda lime glass, and cuts (removes) infrared light.

That is, the solid-state imaging element 11, glass substrate 12, and IRCF 14 are layered and bonded together with transparent adhesives 13 and 15 to form an integrated structure, which is then connected to the circuit board 17. Note that the solid-state imaging element 11, glass substrate 12, and IRCF 14, which are surrounded by a dashed dotted line in the figure, are bonded together with adhesives 13 and 15 that have approximately the same refractive index to form an integrated structure, and hence will hereinafter be referred to simply as the integrated structure 10.

In addition, the IRCF 14 may be diced into individual pieces during the manufacturing process of the solid-state imaging elements 11 and then attached to the glass substrate 12, or a large-sized IRCF 14 may be attached to the entire surface of a wafer-like glass substrate 12 consisting of a plurality of solid-state imaging elements 11 and then diced into individual solid-state imaging elements 11. Either method may be adopted.

A spacer 20 is configured on the circuit board 17 so as to surround the entire integrated structure of the solid-state imaging element 11, glass substrate 12, and IRCF 14. An actuator 18 is provided on the spacer 20. The actuator 18 is configured in a cylindrical shape, and houses a lens group 16 formed by stacking multiple lenses inside the cylinder, which is driven in the vertical direction in FIG.

With this configuration, the actuator 18 moves the lens group 16 in the vertical direction in Figure 1 (front-back direction relative to the optical axis) to achieve autofocus by adjusting the focus so as to form an image of the subject on the imaging surface of the solid-state imaging element 11 depending on the distance to the subject (not shown), which is at the top of the figure.

<External appearance diagram>
Next, the configuration of the integrated component 10 will be described with reference to Figures 2 to 6. Figure 2 shows a schematic external view of the integrated component 10.

The integrated component 10 shown in Figure 2 is a semiconductor package in which a solid-state imaging element 11 is packaged, the solid-state imaging element 11 being made of a laminated substrate formed by stacking a lower substrate 11a and an upper substrate 11b.

The lower substrate 11a of the laminated substrate constituting the solid-state imaging element 11 has multiple solder balls 11e formed thereon, which are back electrodes for electrically connecting to the circuit board 17 in Figure 1.

On the upper surface of the upper substrate 11b, a color filter 11c of R (red), G (green), or B (blue) and an on-chip lens 11d are formed. The upper substrate 11b is connected to a glass substrate 12 for protecting the on-chip lens 11d via an adhesive 13 made of a glass seal resin in a cavity-less structure.

For example, as shown in FIG. 3A, the upper substrate 11b is formed with a pixel region 21 in which pixel units that perform photoelectric conversion are arranged two-dimensionally in an array, and a control circuit 22 that controls the pixel units, and the lower substrate 11a is formed with a logic circuit 23 such as a signal processing circuit that processes pixel signals output from the pixel units.

Alternatively, as shown in FIG. 3B, only the pixel region 21 may be formed on the upper substrate 11b, and the control circuit 22 and logic circuit 23 may be formed on the lower substrate 11a.

As described above, by forming and stacking the logic circuit 23 or both the control circuit 22 and the logic circuit 23 on the lower substrate 11a separate from the upper substrate 11b of the pixel region 21, the size of the imaging device 1 can be reduced compared to a case in which the pixel region 21, the control circuit 22, and the logic circuit 23 are arranged in a planar direction on a single semiconductor substrate.

In the following, the upper substrate 11b on which at least the pixel region 21 is formed will be referred to as the pixel sensor substrate 11b, and the lower substrate 11a on which at least the logic circuit 23 is formed will be referred to as the logic substrate 11a.

<Example of laminated substrate configuration>
FIG. 4 shows an example of the circuit configuration of the solid-state imaging device 11. As shown in FIG.

The solid-state imaging element 11 includes a pixel array section 33 in which pixels 32 are arranged in a two-dimensional array, a vertical drive circuit 34, a column signal processing circuit 35, a horizontal drive circuit 36, an output circuit 37, a control circuit 38, and an input/output terminal 39.

Each pixel 32 includes a photodiode as a photoelectric conversion element and a plurality of pixel transistors. An example of the circuit configuration of pixel 32 will be described later with reference to FIG. 5.

Pixel 32 can also have a shared pixel structure. This pixel sharing structure is composed of multiple photodiodes, multiple transfer transistors, one shared floating diffusion, and each of the other pixel transistors. In other words, in a shared pixel, the photodiodes and transfer transistors constituting multiple unit pixels are configured to share each of the other pixel transistors.

The control circuit 38 receives an input clock and data instructing the operating mode, etc., and outputs data such as internal information of the solid-state imaging element 11. That is, the control circuit 38 generates clock signals and control signals that serve as the basis for the operation of the vertical drive circuit 34, column signal processing circuit 35, horizontal drive circuit 36, etc., based on the vertical synchronization signal, horizontal synchronization signal, and master clock. The control circuit 38 then outputs the generated clock signals and control signals to the vertical drive circuit 34, column signal processing circuit 35, horizontal drive circuit 36, etc.

The vertical drive circuit 34 is configured, for example, by a shift register, selects a specific pixel drive wiring 40, supplies a pulse to the selected pixel drive wiring 40 for driving the pixels 32, and drives the pixels 32 row by row. That is, the vertical drive circuit 34 selects and scans each pixel 32 of the pixel array section 33 in the vertical direction row by row, and supplies a pixel signal based on a signal charge generated in the photoelectric conversion section of each pixel 32 according to the amount of light received to the column signal processing circuit 35 through the vertical signal line 41.

The column signal processing circuit 35 is arranged for each column of pixels 32, and performs signal processing such as noise removal for each pixel column on signals output from one row of pixels 32. For example, the column signal processing circuit 5 performs signal processing such as CDS (Correlated Double Sampling) for removing pixel-specific fixed pattern noise and AD conversion.

The horizontal drive circuit 36 is, for example, composed of a shift register, and sequentially outputs horizontal scanning pulses to select each of the column signal processing circuits 35 in turn, and output pixel signals from each of the column signal processing circuits 35 to the horizontal signal line 42.

The output circuit 37 processes and outputs the signals sequentially supplied from each of the column signal processing circuits 35 through the horizontal signal line 42. The output circuit 37 may perform only buffering, or may perform black level adjustment, column variation correction, various digital signal processing, etc. The input/output terminal 39 exchanges signals with the outside.

The solid-state imaging element 11 configured as described above is a CMOS image sensor called a column AD type, in which a column signal processing circuit 35 that performs CDS processing and AD conversion processing is arranged for each pixel column.

<Pixel circuit configuration example>
FIG. 5 shows an equivalent circuit of the pixel 32 .

Pixel 32 shown in Figure 5 shows a configuration that realizes an electronic global shutter function.

The pixel 32 has a photodiode 51 as a photoelectric conversion element, a first transfer transistor 52, a memory section (MEM) 53, a second transfer transistor 54, an FD (floating diffusion region) 55, a reset transistor 56, an amplification transistor 57, a selection transistor 58, and an emission transistor 59.

The photodiode 51 is a photoelectric conversion unit that generates and accumulates an electric charge (signal charge) according to the amount of light received. The anode terminal of the photodiode 51 is grounded, and the cathode terminal is connected to the memory unit 53 via the first transfer transistor 52. The cathode terminal of the photodiode 51 is also connected to a discharge transistor 59 for discharging unnecessary electric charges.

When the first transfer transistor 52 is turned on by the transfer signal TRX, it reads out the charge generated by the photodiode 51 and transfers it to the memory unit 53. The memory unit 53 is a charge holding unit that temporarily holds the charge until it is transferred to the FD 55.

When the second transfer transistor 54 is turned on by the transfer signal TRG, it reads out the charge stored in the memory unit 53 and transfers it to the FD 55.

The FD 55 is a charge holding unit that holds the charge read out from the memory unit 53 in order to read it out as a signal. When the reset transistor 56 is turned on by a reset signal RST, the charge stored in the FD 55 is discharged to a constant voltage source VDD, thereby resetting the potential of the FD 55.

The amplifier transistor 57 outputs a pixel signal according to the potential of the FD 55. That is, the amplifier transistor 57 forms a source follower circuit together with the load MOS 60 as a constant current source, and a pixel signal indicating a level according to the charge stored in the FD 55 is output from the amplifier transistor 57 to the column signal processing circuit 35 (FIG. 4) via the selection transistor 58. The load MOS 60 is arranged, for example, in the column signal processing circuit 35.

The selection transistor 58 is turned on when pixel 32 is selected by the selection signal SEL, and outputs the pixel signal of pixel 32 to the column signal processing circuit 35 via the vertical signal line 41.

When the discharge transistor 59 is turned on by the discharge signal OFG, it discharges unnecessary charges accumulated in the photodiode 51 to the constant voltage source VDD.

The transfer signals TRX and TRG, the reset signal RST, the discharge signal OFG, and the selection signal SEL are supplied from the vertical drive circuit 34 via the pixel drive wiring 40.

The operation of pixel 32 is briefly explained.

First, before exposure begins, a high-level discharge signal OFG is supplied to the discharge transistor 59, turning on the discharge transistor 59, discharging the charge stored in the photodiode 51 to the constant voltage source VDD, and resetting the photodiodes 51 of all pixels.

After the photodiode 51 is reset, the discharge transistor 59 is turned off by a low-level discharge signal OFG, and exposure begins for all pixels in the pixel array section 33.

After a predetermined exposure time has elapsed, in all pixels of the pixel array section 33, the first transfer transistor 52 is turned on by the transfer signal TRX, and the charge accumulated in the photodiode 51 is transferred to the memory section 53.

After the first transfer transistor 52 is turned off, the charge held in the memory unit 53 of each pixel 32 is read out row by row, sequentially, to the column signal processing circuit 35. In the readout operation, the second transfer transistor 54 of the pixel 32 in the readout row is turned on by the transfer signal TRG, and the charge held in the memory unit 53 is transferred to the FD 55. Then, the selection transistor 58 is turned on by the selection signal SEL, and a signal indicating a level corresponding to the charge stored in the FD 55 is output from the amplification transistor 57 via the selection transistor 58 to the column signal processing circuit 35.

As described above, pixel 32 having the pixel circuit of Figure 5 is capable of setting the exposure time to be the same for all pixels in pixel array section 33, temporarily storing electric charge in memory section 53 after exposure is completed, and performing global shutter type operation (imaging) in which electric charge is read out sequentially row by row from memory section 53.

The circuit configuration of pixel 32 is not limited to the configuration shown in Figure 5, and for example, a circuit configuration that does not have a memory section 53 and operates using a so-called rolling shutter method can be adopted.

<Basic Structure Example of Solid-State Imaging Device>
Next, a detailed structure of the solid-state imaging element 11 will be described with reference to Fig. 6. Fig. 6 is an enlarged cross-sectional view showing a part of the solid-state imaging element 11.

In the logic substrate 11a, a multi-layer wiring layer 82 is formed on the upper side (pixel sensor substrate 11b side) of a semiconductor substrate 81 (hereinafter referred to as silicon substrate 81) made of, for example, silicon (Si). This multi-layer wiring layer 82 constitutes the control circuit 22 and logic circuit 23 in FIG. 3.

The multilayer wiring layer 82 is composed of multiple wiring layers 83, including a topmost wiring layer 83a closest to the pixel sensor substrate 11b, an intermediate wiring layer 83b, and a bottommost wiring layer 83c closest to the silicon substrate 81, and an interlayer insulating film 84 formed between each wiring layer 83.

The multiple wiring layers 83 are formed using, for example, copper (Cu), aluminum (Al), tungsten (W), etc., and the interlayer insulating film 84 is formed, for example, of a silicon oxide film, a silicon nitride film, etc. Each of the multiple wiring layers 83 and the interlayer insulating film 84 may be formed of the same material for all layers, or two or more materials may be used depending on the layer.

A silicon through hole 85 is formed at a predetermined position of the silicon substrate 81, and a connection conductor 87 is embedded in the inner wall of the silicon through hole 85 via an insulating film 86 to form a silicon through electrode (TSV: Through Silicon Via) 88. The insulating film 86 can be formed of, for example, a SiO2 film or a SiN film.

6, an insulating film 86 and a connection conductor 87 are formed along the inner wall surface, and the inside of the silicon through hole 85 is hollow, but depending on the inner diameter, the inside of the silicon through hole 85 may be entirely filled with the connection conductor 87. In other words, the inside of the through hole may be filled with a conductor or may be partially hollow. This also applies to the through chip electrode (TCV: Through Chip Via) 105 described later.

The connection conductor 87 of the silicon through electrode 88 is connected to a rewiring 90 formed on the underside of the silicon substrate 81, and the rewiring 90 is connected to the solder ball 11e. The connection conductor 87 and the rewiring 90 can be made of, for example, copper (Cu), tungsten (W), polysilicon, or the like.

In addition, a solder mask (solder resist) 91 is formed on the underside of the silicon substrate 81 so as to cover the rewiring 90 and the insulating film 86, except for the area where the solder balls 11e are formed.

On the other hand, in the pixel sensor substrate 11b, a multi-layer wiring layer 102 is formed on the underside (the logic substrate 11a side) of a semiconductor substrate 101 (hereinafter referred to as the silicon substrate 101) made of silicon (Si). This multi-layer wiring layer 102 constitutes the pixel circuit of the pixel region 21 in FIG. 3.

The multilayer wiring layer 102 is composed of multiple wiring layers 103, including a top wiring layer 103a closest to the silicon substrate 101, an intermediate wiring layer 103b, and a bottom wiring layer 103c closest to the logic substrate 11a, and an interlayer insulating film 104 formed between each wiring layer 103.

The materials used for the multiple wiring layers 103 and the interlayer insulating film 104 can be the same as the materials for the wiring layer 83 and the interlayer insulating film 84 described above. In addition, like the wiring layer 83 and the interlayer insulating film 84 described above, the multiple wiring layers 103 and the interlayer insulating film 104 may be formed using one or more materials.

In the example of Figure 6, the multilayer wiring layer 102 of the pixel sensor substrate 11b is composed of three wiring layers 103, and the multilayer wiring layer 82 of the logic substrate 11a is composed of four wiring layers 83, but the total number of wiring layers is not limited to this and can be formed with any number of layers.

Within the silicon substrate 101, a photodiode 51 formed by a PN junction is formed for each pixel 32.

Although not shown in the figure, the multilayer wiring layer 102 and the silicon substrate 101 are also formed with a plurality of pixel transistors, such as a first transfer transistor 52 and a second transfer transistor 54, as well as a memory section (MEM) 53.

At predetermined positions of the silicon substrate 101 where the color filter 11c and the on-chip lens 11d are not formed, a silicon through electrode 109 connected to the wiring layer 103a of the pixel sensor substrate 11b and a chip through electrode 105 connected to the wiring layer 83a of the logic substrate 11a are formed.

The chip through electrode 105 and the silicon through electrode 109 are connected by a connection wiring 106 formed on the upper surface of the silicon substrate 101. An insulating film 107 is formed between the silicon through electrode 109 and the silicon substrate 101, and between the chip through electrode 105 and the silicon substrate 101. Furthermore, a color filter 11c and an on-chip lens 11d are formed on the upper surface of the silicon substrate 101 via a planarization film (insulating film) 108.

As described above, the solid-state imaging element 11 shown in Fig. 2 has a laminated structure in which the multilayer wiring layer 102 side of the logic substrate 11a and the multilayer wiring layer 82 side of the pixel sensor substrate 11b are bonded together. In Fig. 6, the bonded surfaces of the multilayer wiring layer 102 side of the logic substrate 11a and the multilayer wiring layer 82 side of the pixel sensor substrate 11b are indicated by dashed lines.

In addition, in the solid-state imaging element 11 of the imaging device 1, the wiring layer 103 of the pixel sensor substrate 11b and the wiring layer 83 of the logic substrate 11a are connected by two through electrodes, a silicon through electrode 109 and a chip through electrode 105, and the wiring layer 83 of the logic substrate 11a and the solder ball (rear electrode) 11e are connected by a silicon through electrode 88 and a rewiring 90. This allows the planar area of the imaging device 1 to be minimized.

Furthermore, by creating a cavity-less structure between the solid-state imaging element 11 and the glass substrate 12 and bonding them together with adhesive 13, the height can also be reduced.

Therefore, the imaging device 1 shown in Figure 1 makes it possible to realize a more compact semiconductor device (semiconductor package).

With the above-described configuration of the imaging device 1, the IRCF 14 is provided on the solid-state imaging element 11 and the glass substrate 12, making it possible to suppress the occurrence of flare and ghosts caused by internal reflection of light.

That is, as shown in the left part of Figure 7, when the IRCF 14 is spaced apart from the glass substrate 12 and is configured near the midpoint between the lens 16 and the glass substrate 12, the incident light is condensed as shown by the solid line, passes through the IRCF 14, the glass substrate 12, and the adhesive 13, enters the solid-state image sensor (CIS) 11 at position F0, and is then reflected at position F0 as shown by the dotted line, generating reflected light.

As shown by the dotted line, a portion of the reflected light reflected at position F0 is reflected, for example, through adhesive 13 and glass substrate 12, by the back surface (the lower surface in Figure 7) R1 of IRCF 14 arranged at a position spaced apart from glass substrate 12, and then again passes through glass substrate 12 and adhesive 13 and enters solid-state imaging element 11 again at position F1.

In addition, as shown by the dotted line, another portion of the reflected light reflected at the focal point F0 passes through, for example, the adhesive 13, the glass substrate 12, and the IRCF 14 arranged at a position spaced apart from the glass substrate 12, and is reflected by the upper surface (the upper surface in Figure 7) R2 of the IRCF 14, and then passes through the IRCF 14, the glass substrate 12, and the adhesive 13 and enters the solid-state imaging element 11 again at position F2.

At these positions F1 and F2, the light that reenters the image generates flare and ghost images due to internal reflection. More specifically, as shown in image P1 in Figure 8, when the illumination L is captured by the solid-state imaging element 11, these appear as flare and ghost images as shown by reflected light R21 and R22.

In contrast, when the IRCF 14 is configured on the glass substrate 12 as in the imaging device 1 shown in the right part of Fig. 7, which corresponds to the configuration of the imaging device 1 in Fig. 1, the incident light shown by the solid line is condensed and passes through the IRCF 14, adhesive 15, glass substrate 12, and adhesive 13 to be incident on the solid-state imaging element 11 at position F0, and is then reflected as shown by the dotted line. The reflected light is then reflected by surface R11 of the lowest lens on the lens group 16 via adhesive 13, glass substrate 12, adhesive 15, and IRCF 14, but because the lens group 16 is located sufficiently far from the IRCF 14, it is reflected to a range where it cannot be fully received by the solid-state imaging element 11.

Here, the solid-state imaging element 11, glass substrate 12, and IRCF 14, which are surrounded by a dashed line in the figure, are bonded together with adhesives 13 and 15 of approximately the same refractive index to form an integrated component 10. In the integrated component 10, the refractive index is unified to suppress the occurrence of internal reflection that occurs at the boundary between layers of different refractive indexes, and for example, re-intrusion at positions F1 and F2, which are near position F0 in the left part of Figure 7, is suppressed.

As a result, when the imaging device 1 in Figure 1 captures illumination L, it can capture an image in which the occurrence of flare and ghosts caused by internal reflection, such as reflected light R21 and R22 in image P1, is suppressed, as shown in image P2 in Figure 8.

As a result, a configuration such as the imaging device 1 of the first embodiment shown in Figure 1 makes it possible to realize a compact and low-profile device configuration, while suppressing the occurrence of flare and ghosts caused by internal reflection.

Image P1 in Figure 8 is an image of illumination L captured at night by an imaging device 1 having the configuration shown on the left in Figure 7, and image P2 is an image of illumination L captured at night by an imaging device 1 (of Figure 1) having the configuration shown on the right in Figure 7.

In the above, an example has been described in which the actuator 18 moves the lens group 16 in the vertical direction in FIG. 1 to adjust the focal length according to the distance to the subject, thereby achieving autofocus. However, it is also possible to not provide the actuator 18 and not adjust the focal length using the lens group 16, and to have the lens function as a so-called fixed focal length lens.

2. Second embodiment
In the first embodiment, an example has been described in which the IRCF 14 is attached to the glass substrate 12 that is attached to the imaging surface side of the solid-state imaging element 11. However, the lowest lens that constitutes the lens group 16 may also be provided on the IRCF 14.

Figure 9 shows an example of the configuration of an imaging device 1 in Figure 1 in which the lens in the lowest layer in the direction of light incidence, out of the lens group 16 consisting of multiple lenses that make up the imaging device 1 in Figure 1, is separated from the lens group 16 and configured on the IRCF 14. Note that in Figure 5, components that have basically the same functions as the components in Figure 1 are given the same reference numerals, and their explanation will be omitted as appropriate.

9 differs from the imaging device 1 in Fig. 1 in that, on the top surface of the IRCF 14 in the figure, lens 131, which is the lowest layer of the lenses constituting lens group 16 in the direction of incidence of light, is provided separately from lens group 16. Note that, although the lens group 16 in Fig. 9 is given the same reference numeral as lens group 16 in Fig. 1, strictly speaking, it differs from lens group 16 in Fig. 1 in that it does not include lens 131, which is the lowest layer of the lenses in the direction of incidence of light.

With the configuration of the imaging device 1 as shown in Figure 9, the IRCF 14 is provided on a glass substrate 12 provided on the solid-state imaging element 11, and further, the lowest layer lens 131 constituting the lens group 16 is provided on the IRCF 14, making it possible to suppress the occurrence of flare and ghosts due to internal reflection of light.

That is, as shown in the left part of Figure 10, when lens 131, which is the lowest layer in the direction of incidence of light from lens group 16, is provided on glass substrate 12, and IRCF 14 is spaced apart from lens 131 and configured near the midpoint between lens group 16 and lens 131, the incident light shown by the solid line is concentrated and passes through IRCF 14, lens 131, glass substrate 12, and adhesive 13 to enter solid-state imaging element 11 at position F0, and is then reflected from position F0 as shown by the dotted line, generating reflected light.

As shown by the dotted line, a portion of the reflected light reflected at position F0 is reflected, for example, through adhesive 13, glass substrate 12, and lens 131 by the back surface (the lower surface in Figure 2) R31 of IRCF 14 arranged at a position spaced apart from lens 131, and then enters the solid-state imaging element 11 again at position F11 via lens 131, glass substrate 12, and adhesive 13.

In addition, as shown by the dotted line, another portion of the reflected light reflected at the focal point F0 passes through, for example, the adhesive 13, the glass substrate 12, and the lens 131, as well as the IRCF 14 arranged at a position spaced apart from the lens 131, and is reflected off the upper surface (the upper surface in Figure 7) R32 of the IRCF 14, and then passes through the IRCF 14, the lens 131, the glass substrate 12, and the adhesive 13 and enters the solid-state imaging element 11 again at position F12.

The light that re-enters positions F11 and F12 appears as flare or ghosting on the solid-state imaging element 11. This is essentially the same as the principle that occurs when reflected light R21, R21 of the illumination L in image P1 described with reference to Figure 8 re-enters positions F1 and F2 in Figure 7.

In contrast, when the lowest lens 131 of the lens group 16 is configured on the IRCF 14, as shown in the right part of Figure 10, similar to the configuration in the imaging device 1 of Figure 9, the incident light is condensed as shown by the solid line, passes through the lens 131, IRCF 14, adhesive 15, glass substrate 12, and adhesive 13, enters the solid-state imaging element 11 at position F0, and is then reflected and reflected by surface R41 on the lens group 16 at a sufficiently distant position via adhesive 13, glass substrate 12, adhesive 15, IRCF 14, and lens 131 as shown by the dotted line.However, since the light is reflected to a range that is almost impossible to receive by the solid-state imaging element 11, the occurrence of flare and ghosting can be suppressed.

In other words, the solid-state imaging element 11, adhesive 13, glass substrate 12, and IRCF 14 are bonded together with adhesives 13 and 15 of approximately the same refractive index to form an integrated structure. Therefore, in the integrated structure, which is the integrated structure, the integrated structure portion 10 surrounded by the dotted line in the figure, the refractive index is unified, thereby suppressing the occurrence of internal reflection that occurs at the boundary between layers of different refractive indexes. For example, as shown in the left part of Figure 10, the incidence of reflected light, etc. at positions F11 and F12 near position F0 is suppressed.

As a result, a configuration such as the imaging device 1 of the second embodiment shown in Figure 10 makes it possible to realize a compact and low-profile device configuration, while suppressing the occurrence of flare and ghosts caused by internal reflection.

3. Third embodiment
In the second embodiment, an example has been described in which the lens 131 in the lowest layer is provided on the IRCF 14, but the lens 131 in the lowest layer and the IRCF 14 may be bonded together with an adhesive.

Figure 11 shows an example of the configuration of an imaging device 1 in which the lowest layer lens 131 and IRCF 14 are bonded together with an adhesive. In the imaging device 1 of Figure 11, components having the same functions as those of the imaging device 1 of Figure 9 are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

That is, the imaging device 1 in Figure 11 differs from the imaging device 1 in Figure 9 in that the lowest layer lens 131 and IRCF 14 are bonded together with a transparent adhesive 151, i.e., an adhesive having approximately the same refractive index.

Even with a configuration such as the imaging device 1 of Figure 11, it is possible to suppress the occurrence of flare and ghosting, just like the imaging device 1 of Figure 9.

In addition, if the lens 131 is not very flat, there is a risk that IRCF 14 will become misaligned with respect to the optical axis of lens 131 even if an attempt is made to fix it to IRCF 14 without using adhesive 151. However, by bonding lens 131 and IRCF 14 together with adhesive 151, it becomes possible to fix IRCF 14 without misalignment with the optical axis of lens 131 even if the lens 131 is not very flat, and it becomes possible to suppress image distortion caused by misalignment of the optical axis.

4. Fourth embodiment
In the second embodiment, an example has been described in which the lowest layer lens 131 is provided on the IRCF 14 in the direction of light incidence, but not only the lowest layer lens 131 but also a plurality of lens groups constituting the lowest layer of the lens group 16 may be provided on the IRCF 14.

Figure 12 shows an example of the configuration of an imaging device 1 in which a lens group 16 consisting of a plurality of lenses constituting the lowest layer in the direction of incidence is configured on an IRCF 14. Note that in the imaging device 1 of Figure 12, components having the same functions as those of the imaging device 1 of Figure 9 are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

That is, the imaging device 1 in Fig. 12 differs from the imaging device 1 in Fig. 9 in that, instead of the lens 131, a lens group 171 made up of a plurality of lenses constituting the lowest layer of the lens group 16 in the direction of light incidence is provided on the IRCF 14. Note that, although Fig. 12 shows an example of the lens group 171 made up of two lenses, the lens group 171 may be made up of more than one lens.

Even with this configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, since lens group 171, which is composed of a plurality of lenses constituting the lowest layer of the plurality of lenses constituting lens group 16, is configured on IRCF 14, the number of lenses constituting lens group 16 can be reduced, and lens group 16 can be made lighter. This makes it possible to reduce the amount of driving force of actuator 18 used for autofocus, thereby enabling actuator 18 to be made smaller and consume less power.

In addition, the lens 131 in the imaging device 1 of Figure 11 of the third embodiment may be replaced with a lens group 171 and attached to the IRCF 14 with a transparent adhesive 151.

<5. Fifth embodiment>
In the second embodiment, an example has been described in which glass substrate 12 is attached onto solid-state imaging element 11 with adhesive 13, and IRCF 14 is attached onto glass substrate 12 with adhesive 15. However, glass substrate 12, adhesive 15, and IRCF 14 may be replaced with a configuration having both the functions of glass substrate 12 and IRCF 14, and this may be attached onto solid-state imaging element 11 with adhesive 13.

Figure 13 shows an example of the configuration of an imaging device 1 in which the glass substrate 12, adhesive 15, and IRCF 14 are replaced with a configuration that combines the functions of the glass substrate 12 and the IRCF 14, and is attached to the solid-state imaging element 11 with adhesive 13, and a bottom-layer lens 131 is provided on top of that. Note that in the imaging device 1 of Figure 13, components having the same functions as those of the imaging device 1 of Figure 9 are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

That is, the imaging device 1 in Figure 13 differs from the imaging device 1 in Figure 9 in that the glass substrate 12 and IRCF 14 are replaced with an IRCF glass substrate 14' having the functions of the glass substrate 12 and the functions of the IRCF 14 and is attached to the solid-state imaging element 11 with adhesive 13, and further, the lowest layer lens 131 is provided on the IRCF 14'.

With such a configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

That is, currently, in order to miniaturize the solid-state imaging element 11, a small solid-state imaging element can be realized by bonding the solid-state imaging element 11 to a glass substrate 12 called a CSP (Chip Size Package) structure, and processing the solid-state imaging element 11 thinly using the glass substrate as a base substrate. In Fig. 13, the IRCF glass substrate 14' functions as the IRCF 14 as well as the highly flat glass substrate 12, making it possible to realize a low height.

In addition, the glass substrate 12, adhesive 15, and IRCF 14 in the imaging device 1 of Figures 1, 11, and 12, which are the first, third, and fourth embodiments, may be replaced with an IRCF glass substrate 14' that has the functions of the glass substrate 12 and the functions of the IRCF 14.

6. Sixth embodiment
In the fourth embodiment, an example has been described in which a glass substrate 12 is attached onto a solid-state imaging element 11 having a CSP structure with an adhesive 13, an IRCF 14 is further attached onto the glass substrate 12 with an adhesive 15, and a lens group 171 consisting of a plurality of lenses in the lowest layer among the plurality of lenses that constitute the lens group 16 is provided on the IRCF 14. However, instead of the solid-state imaging element 11 having a CSP structure, a solid-state imaging element 11 having a COB (Chip on Board) structure may be used.

Figure 14 shows an example of a configuration in which the glass substrate 12 and IRCF 14 in the imaging device 1 in Figure 12 are replaced with an IRCF glass substrate 14' that has the functions of the glass substrate 12 and the IRCF 14, and a solid-state imaging element 11 with a COB (Chip on Board) structure is used instead of the solid-state imaging element 11 with a CSP structure. In the imaging device 1 in Figure 14, components with the same functions as those in the imaging device 1 in Figure 12 are given the same reference numerals, and their explanation will be omitted as appropriate.

That is, the imaging device 1 in Figure 14 differs from the imaging device 1 in Figure 12 in that the glass substrate 12 and the IRCF 14 are replaced with an IRCF glass substrate 14' having the functions of the glass substrate 12 and the functions of the IRCF 14, and that a solid-state imaging element 91 having a COB (Chip on Board) structure is used instead of the solid-state imaging element 11 having a CSP structure.

Even with this configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 12.

In recent years, the CSP structure has become common in order to miniaturize the solid-state imaging element 11 as the imaging device 1 becomes smaller, but the CSP structure is more expensive than the COB structure solid-state imaging element 11 because of the complex processing required, such as bonding to the glass substrate 12 or IRCF glass substrate 14' and wiring the terminals of the solid-state imaging element 11 to the back side of the light receiving surface. Therefore, in addition to the CSP structure, a COB structure solid-state imaging element 91 connected to the circuit board 17 by wire bonds 92 or the like may be used.

By using a solid-state imaging element 91 with a COB structure, connection to the circuit board 17 can be made easy, which simplifies processing and reduces costs.

In addition, the solid-state imaging element 11 having a CSP structure in the imaging device 1 of the first to third embodiments and the fifth embodiment of Figures 1, 9, 11 and 13 may be replaced with a solid-state imaging element 11 having a COB (Chip on Board) structure.

7. Seventh embodiment
In the second embodiment, an example has been described in which a glass substrate 12 is provided on a solid-state imaging element 11, and an IRCF 14 is further provided on the glass substrate. However, it is also possible to provide an IRCF 14 on a solid-state imaging element 11, and then provide a glass substrate 12 on the IRCF 14.

Figure 15 shows an example configuration of an imaging device 1 in which a glass substrate 12 is used, an IRCF 14 is provided on a solid-state imaging element 11, and a glass substrate 12 is further provided on the IRCF 14.

The imaging device 1 in Figure 15 differs from the imaging device 1 in Figure 9 in that the glass substrate 12 and the IRCF 14 are swapped, the IRCF 14 is attached to the solid-state imaging element 11 with a transparent adhesive 13, and the glass substrate 12 is further attached to the IRCF 14 with a transparent adhesive 15, and a lens 131 is provided on the glass substrate 12.

With such a configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, due to its characteristics, the IRCF 14 generally has low flatness due to the influence of temperature and external disturbances, which may cause distortion in the image on the solid-state imaging element 11.

As a result, it is common to use special materials to maintain flatness, such as by applying a coating material to both sides of the IRCF14, but this increases costs.

In contrast, in the imaging device 1 of Figure 15, the IRCF 14, which has low flatness, is sandwiched between the solid-state imaging element 11 and the glass substrate 12, which have high flatness, making it possible to ensure flatness at low cost and reduce image distortion.

Therefore, the imaging device 1 in Fig. 15 can suppress the occurrence of flare and ghosting, and can also suppress image distortion caused by the characteristics of the IRCF 14. In addition, it is not necessary to coat the image with a special material to maintain flatness, which can reduce costs.

In addition, in the imaging device 1 of the first, third and fourth embodiments shown in Figures 1, 11 and 12, the glass substrate 12 and the IRCF 14 may be interchanged and attached with adhesives 13 and 15.

8. Eighth embodiment
In the first embodiment, an example has been described in which IRCF 14 is used as a configuration for cutting infrared light. However, a configuration other than IRCF 14 may be used as long as it is capable of cutting infrared light. For example, an infrared-cutting resin may be applied instead of IRCF 14.

Figure 16 shows an example of the configuration of an imaging device 1 in which an infrared light blocking resin is used instead of the IRCF 14. In the imaging device 1 of Figure 16, components having the same functions as those of the imaging device 1 of Figure 1 are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

That is, the imaging device 1 in Fig. 16 differs from the imaging device 1 in Fig. 1 in that an infrared light cut resin 211 is provided instead of the IRCF 14. The infrared light cut resin 211 is provided, for example, by coating.

Even with this configuration, it is possible to suppress the occurrence of flare and ghosting, just like the imaging device 1 of Figure 1.

In addition, in recent years, improvements have been made to resins, and those with infrared blocking effects have become common, and it is known that infrared light blocking resin 211 can be applied to the glass substrate 12 during the production of the CSP type solid-state imaging element 11.

In addition, an infrared light cut resin 211 may be used instead of the IRCF 14 in the imaging device 1 of the second to fourth embodiments and the seventh embodiment of Figures 9, 11, 12, and 15.

9. Ninth embodiment
In the second embodiment, when a glass substrate 12 is used, an example has been described in which a flat substrate is provided in close contact with the solid-state imaging element 11 without any cavities, but it is also possible to provide a cavity between the glass substrate 12 and the solid-state imaging element 11.

Figure 17 shows an example of the configuration of an imaging device 1 in which a cavity is provided between a glass substrate 12 and a solid-state imaging element 11. In the imaging device 1 of Figure 17, components having the same functions as those of the imaging device 1 of Figure 9 are given the same reference numerals, and descriptions thereof will be omitted as appropriate.

That is, the imaging device 1 in Fig. 17 differs from the imaging device in Fig. 9 in that a glass substrate 231 with a surrounding convex portion 231a is provided instead of the glass substrate 12. The surrounding convex portion 231a comes into contact with the solid-state imaging element 11, and the convex portion 231a is adhered by a transparent adhesive 232, forming a cavity 231b consisting of an air layer between the imaging surface of the solid-state imaging element 11 and the glass substrate 231.

With such a configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, in place of the glass substrate 12 in the imaging device 1 of the first, third, fourth and eighth embodiments of Figures 1, 11, 12 and 16, a glass substrate 231 may be used and only the convex portion 231a may be adhered by adhesive 232, thereby forming a cavity 231b.

<10. Tenth embodiment>
In the second embodiment, an example has been given in which the lowest lens 131 of the lens group 16 is configured on the IRCF 14 provided on the glass substrate 12. However, instead of the IRCF 14 on the glass substrate 12, the lens 131 may be configured by a coating material of an organic multilayer film having an infrared light blocking function.

Figure 18 shows an example configuration of an imaging device 1 in which, instead of the IRCF 14 on the glass substrate 12, an organic multilayer film coating material with infrared light cutting function is used.

The imaging device 1 in Figure 18 differs from the imaging device 1 in Figure 9 in that instead of the IRCF 14 on the glass substrate 12, it is constructed with an organic multilayer coating material 251 that has an infrared light cutting function.

With such a configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, instead of the IRCF 14 in the imaging device 1 of the first, third, fourth, seventh and ninth embodiments of Figures 1, 6, 7, 10 and 12, an organic multilayer coating material 251 having an infrared light cutting function may be used.

11. Eleventh embodiment
In the tenth embodiment, an example has been described in which the lens 131 in the lowest layer of the lens group 16 is provided on the organic multilayer coating material 251 having an infrared light cutting function, instead of the IRCF 14 on the glass substrate 12. However, the lens 131 may be further provided with an AR (Anti Reflection) coating.

Figure 19 shows an example configuration of an imaging device 1 in which the lens 131 in the imaging device 1 of Figure 13 is AR coated.

That is, the imaging device 1 in Fig. 19 differs from the imaging device 1 in Fig. 18 in that a lens 271 in the lowest layer of the lens group 16, which is coated with an AR coating 271a, is provided instead of the lens 131. The AR coating 271a can be formed by, for example, vacuum deposition, sputtering, or WET coating.

With such a configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, the AR coating 271a of the lens 271 suppresses internal reflection of the reflected light from the solid-state imaging element 11, making it possible to suppress the occurrence of flare and ghosting with greater precision.

In addition, instead of the lens 131 in the imaging device 1 of the second, third, fifth, seventh, ninth and tenth embodiments of Figs. 9, 11, 13, 15, 17 and 18, a lens 271 with an AR coating 271a may be used. Also, an AR coating similar to the AR coating 271a may be applied to the surface (the top surface in the figure) of the lens group 171 in the imaging device 1 of Figs. 12 and 14 of the fourth and sixth embodiments.

The AR coating 271a is preferably a single layer or multi-layer structure film of the following films. That is, the AR coating 271a is, for example, a transparent silicon-based resin, an acrylic-based resin, an epoxy-based resin, a styrene-based resin, or the like resin, an insulating film mainly composed of Si (silicon), C (carbon), and H (hydrogen) (e.g., SiCH, SiCOH, and SiCNH), an insulating film mainly composed of Si (silicon) and N (nitrogen) (e.g., SiON and SiN), a SiO2 film, a P-SiO film, and an HDP-SiO film formed using at least one of the material gases such as silicon hydroxide, alkylsilane, alkoxysilane, and polysiloxane, and an oxidizing agent.

<12. Twelfth embodiment>
In the eleventh embodiment, an example has been described in which a lens 271 with an AR (Anti Reflection) coating 271 a is used instead of the lens 131. However, as long as the anti-reflection function can be realized, a configuration other than an AR coating may be used. For example, a moth-eye structure, which is a minute uneven structure that prevents reflection, may be used.

Figure 20 shows an example configuration of an imaging device 1 in which a lens 291 having a moth-eye structure and anti-reflection function is provided instead of the lens 131 in the imaging device 1 of Figure 19.

That is, the imaging device 1 in Figure 20 differs from the imaging device 1 in Figure 18 in that, instead of the lens 131, a lens 291 in the lowest layer of the lens group 16 is provided which is treated with an anti-reflection treatment 291a that has been treated to form a moth-eye structure.

Even with this configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 18.

In addition, the lens 291 has an anti-reflection processing section 291a that has been treated to have a moth-eye structure, which suppresses the internal reflection of the reflected light from the solid-state imaging element 11, making it possible to suppress the occurrence of flare and ghosting with higher accuracy. Note that the anti-reflection processing section 291a may be one that has been treated with an anti-reflection process other than a moth-eye structure, as long as it can achieve the anti-reflection function.

The anti-reflection treatment 291a is preferably a single layer or multi-layer structure of the following films. That is, the anti-reflection treatment 291a is, for example, a transparent silicone resin, an acrylic resin, an epoxy resin, a styrene resin, or the like resin, an insulating film mainly composed of Si (silicon), C (carbon), and H (hydrogen) (for example, SiCH, SiCOH, and SiCNH), an insulating film mainly composed of Si (silicon) and N (nitrogen) (for example, SiON and SiN), a SiO2 film, a P-SiO film, an HDP-SiO film, or the like formed using at least one of the material gases and an oxidizing agent such as silicon hydroxide, alkylsilane, alkoxysilane, and polysiloxane.

In addition, instead of the lens 131 in the imaging device 1 of Figures 9, 11, 13, 15, 17, and 18, which are the second, third, fifth, seventh, ninth, and tenth embodiments, a lens 291 with an anti-reflection treatment unit 291a may be used. Also, the surface of the lens group 171 in the imaging device 1 of Figures 12 and 14, which are the fourth and sixth embodiments, may be subjected to an anti-reflection treatment similar to that of the anti-reflection treatment unit 291a.

<13. Thirteenth embodiment>
In the fourth embodiment, an example has been described in which the lens 131 in the lowest layer of the lens group 16 is provided on the IRCF 14, but this may be replaced with a configuration having an infrared light cutting function and a function similar to that of the lens 131 in the lowest layer.

Figure 21 shows an example configuration of an imaging device 1 in which, instead of the IRCF 14 and the lens 131 in the lowest layer of the lens group 16 in the imaging device 1 of Figure 9, an infrared light cutting lens having an infrared light cutting function and a function similar to that of the lens in the lowest layer of the lens group 16 is provided.

That is, the imaging device 1 in Figure 21 differs from the imaging device 1 in Figure 9 in that an infrared light cut lens 301 with an infrared light cut function is provided instead of the IRCF 14 and the lens 131 in the lowest layer of the lens group 16.

Even with this configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, since the infrared light cut lens 301 has both an infrared light cut function and a function as the lens 131 in the lowest layer of the lens group 16, it is not necessary to provide the IRCF 14 and the lens 131 separately, and therefore it is possible to make the device configuration of the imaging device 1 smaller and thinner. In addition, instead of the lens group 171 and IRCF 14 in the imaging device 1 of FIG. 12, which is the fourth embodiment, it is possible to replace them with an infrared light cut lens that has both an infrared light cut function and a function as the lens group 171 consisting of a plurality of lenses in the lowest layer of the lens group 16.

<14. Fourteenth embodiment>
It is known that stray light is likely to enter from the peripheral portion of the light receiving surface of the solid-state imaging element 11. Therefore, a black mask may be provided on the peripheral portion of the light receiving surface of the solid-state imaging element 11 to suppress the intrusion of stray light and thereby suppress the occurrence of flare and ghosting.

The left part of Figure 22 shows an example configuration of an imaging device 1 in which, instead of the glass substrate 12 in the imaging device 1 of Figure 18, a glass substrate 321 is provided with a black mask 321a that blocks light from the edges of the light receiving surface of the solid-state imaging element 11.

That is, the imaging device 1 on the left side of Fig. 22 differs from the imaging device 1 in Fig. 18 in that, instead of the glass substrate 12, a glass substrate 321 having a black mask 321a made of a light-shielding film applied to the edge portion Z2 is provided, as shown in the right side of Fig. 22. The black mask 321a is applied to the glass substrate 321 by photolithography or the like. Note that no black mask is applied to the center portion Z1 of the glass substrate 321 on the right side of Fig. 22.

With such a configuration, it is possible to suppress the occurrence of flare and ghosting, similar to the imaging device 1 of Figure 9.

In addition, since the glass substrate 321 has a black mask 321a applied to the peripheral portion Z2, it is possible to suppress the intrusion of stray light from the peripheral portion, thereby making it possible to suppress the occurrence of flare and ghosting caused by stray light.

The black mask 321a may be provided not only on the glass substrate 321 but also on other components as long as it can prevent stray light from entering the solid-state imaging element 11. For example, it may be provided on the organic multilayer coating material 251 or lens 131 having an infrared light cutting function, or it may be provided on the IRCF 14, the IRCF glass substrate 14', the glass substrate 231, the lens group 171, the lenses 271, 291, the infrared light cutting resin 211, the infrared light cutting lens 301, etc. In this case, if the surface has low flatness and the black mask cannot be applied by photolithography, the black mask may be applied to the surface with low flatness by, for example, inkjet printing.

As described above, according to the present disclosure, it is possible to reduce flare and ghosting caused by internal reflection of light from solid-state imaging elements that occurs as the device is made smaller, and it is also possible to achieve high pixel counts, high image quality, and compact size without compromising the performance of the imaging device.

<15. Fifteenth embodiment>
In the above, an example has been described in which the lenses 131, 271, 291, the lens group 171, or the infrared light cut lens 301 is joined by bonding or pasting onto the rectangular solid-state imaging element 11.

However, when any of the rectangular lenses 131, 271, 291, lens group 171, and infrared light cut lens 301 are adhered or attached to a solid-state imaging element 11 of approximately the same size, the areas near the corners tend to peel off, and peeling of the corners of the lens 131 may prevent incident light from properly entering the solid-state imaging element 11, resulting in the risk of flare or ghosting.

Therefore, when any of the rectangular lenses 131, 271, 291, lens group 171, and infrared light cut lens 301 are adhered or affixed to the solid-state imaging element 11, they may be set to have outer dimensions smaller than the outer dimensions of the solid-state imaging element 11, and an effective area may be set near the center of the lens and an ineffective area may be set on the outer periphery, so that the lens is less likely to peel off, or the incident light can be effectively collected even if the edges are slightly peeled off.

That is, when the lens 131 is adhered or affixed to the glass substrate 12 provided on the solid-state imaging element 11, for example, as shown in Fig. 23, the outer dimensions of the lens 131 are made smaller than the glass substrate 12 on the solid-state imaging element 11, and a non-effective area 131b is set on the outer periphery of the lens 131, and an effective area 131a is set inside it. Note that a glass substrate 231 may be provided on the solid-state imaging element 11 instead of the glass substrate 12.

In addition, the configuration in Figure 23 omits the IRCF 14 and adhesive 15 in the integrated component 10 of the imaging device 1 in Figure 9, but this is omitted only for the sake of convenience of explanation, and it goes without saying that they may also be provided between the lens 131 and the glass substrate 12.

Furthermore, here, the effective area 131a is an area of the lens 131 where the incident light is incident, which has an aspheric shape and functions effectively to focus the incident light on a photoelectrically convertible area of the solid-state imaging element 11. In other words, the effective area 131a is a concentric structure in which an aspheric lens structure is formed, which is an area circumscribing the outer periphery of the lens, and which focuses the incident light on a photoelectrically convertible imaging surface of the solid-state imaging element 11.

On the other hand, the non-effective area 131b is an area that does not necessarily function as a lens to focus incident light entering the lens 131 onto an area that is photoelectrically converted in the solid-state imaging element 11.

However, in the non-effective region 131b, it is desirable to have a structure that extends the structure that functions as a lens having a partially aspherical shape at the boundary with the effective region 131a. In this way, by providing the structure that functions as a lens in the non-effective region 131b and extending it near the boundary with the effective region 131a, it becomes possible to properly focus incident light on the imaging surface of the solid-state imaging element 11 even if misalignment occurs when the lens 131 is adhered or pasted to the glass substrate 12 on the solid-state imaging element 11.

23, the size of the glass substrate 12 on the solid-state imaging element 11 is height Vs in the vertical direction (Y direction) × width Hs in the horizontal direction (X direction), and a lens 131 smaller than the solid-state imaging element 11 (glass substrate 12) and having a size of height Vn in the vertical direction × width Hn in the horizontal direction is glued or attached to the center part inside the glass substrate 12 on the solid-state imaging element 11. Furthermore, a non-effective area 131b that does not function as a lens is set on the outer periphery of the lens 131, and an effective area 131a having a size of height Ve in the vertical direction × width He in the horizontal direction is set inside it.

In other words, in both the horizontal width and the vertical height, the relationship is width and length of the effective area 131a of the lens 131 < width and length of the non-effective area 131b < width and length of the external size of the solid-state imaging element 11 (upper glass substrate 12), and the central positions of the lens 131, effective area 131a and non-effective area 131b are approximately identical.

In addition, in Figure 23, the upper part of the figure shows a top view viewed from the light incident direction when lens 131 is adhered or affixed to glass substrate 12 on solid-state imaging element 11, and the lower left part of the figure shows an external perspective view when lens 131 is adhered or affixed to glass substrate 12 on solid-state imaging element 11.

Furthermore, the lower right corner of Figure 23 shows the boundary B1 between the side portion of the lens 131 and the glass substrate 12 at the end of the external oblique view when the lens 131 is adhered or attached to the glass substrate 12 on the solid-state imaging element 11, the boundary B2 of the outside of the non-effective area 131b, and the boundary B3 between the outside of the effective area 131a and the inside of the non-effective area 131b.

23 shows an example in which the side edge of lens 131 is perpendicular to glass substrate 12 on solid-state imaging element 11. For this reason, in the top view of FIG. 23, outer boundary B2 of non-effective area 131b is formed on the upper surface of lens 131, and boundary B1 between effective area 131a and non-effective area 131b is formed on the lower surface of lens 131, and is therefore of the same size. As a result, in the upper part of FIG. 23, the outer periphery (boundary B1) of lens 131 and the outer periphery (boundary B2) of non-effective area 131b are expressed as having the same external shape.

With this configuration, a space is created between the side of the lens 131 that forms the outer periphery and the outer periphery of the glass substrate 12 on the solid-state imaging element 11, making it possible to suppress interference between the side of the lens 131 and other objects, and making it possible to create a configuration that is less likely to peel off from the glass substrate 12 on the solid-state imaging element 11.

In addition, by setting the effective area 131a of the lens 131 within the non-effective area 131b, even if the peripheral portion peels off to some extent, it is possible to appropriately focus the incident light on the imaging surface of the solid-state imaging element 11. In addition, when the lens 131 peels off, the interfacial reflection increases, and flare and ghosting worsen, so by suppressing the peeling, it is possible to suppress the occurrence of flare and ghosting.

In addition, in Figure 23, an example has been described in which the lens 131 is adhered or affixed to the glass substrate 12 on the solid-state imaging element 11, but it may of course be any of the lenses 271, 291, the lens group 171, and the infrared light cut lens 301.

<Modifications of Lens Outer Shape>
In the above, an example has been described in which an effective area 131a is set in the center of the lens 131, a non-effective area 131b is set on its outer periphery, and the effective area 131a is smaller in size than the outer periphery of the solid-state imaging element 11 (upper glass substrate 12), and all four corners of the external shape of the lens 131 are configured with acute-angled shapes.

However, as long as the size of the lens 131 is set smaller than the size of the solid-state imaging element 11 (upper glass substrate 12), an effective area 131a is set in the center of the lens 131, and a non-effective area 131b is set on the outer periphery, the outer shape may be any other shape.

That is, as shown in the upper left of Fig. 24 (corresponding to Fig. 23), the four corner regions Z301 in the outer shape of the lens 131 may be configured to have acute-angled shapes. Also, as shown in the lens 131' in the upper right of Fig. 24, the four corner regions Z302 may be configured to have a polygonal shape with obtuse angles.

In addition, as shown by lens 131'' in the center left of Figure 24, the areas Z303 at the four corners of the external shape may be circular in shape.

Furthermore, as shown by lens 131''' in the middle right of Figure 24, the area Z304 at the four corners of the outer shape may have a shape in which small square portions protrude from the four corners. Furthermore, the protruding shape may be a shape other than a square, such as a circle, an ellipse, or a polygon.

In addition, as shown by lens 131'''' in the lower left of Figure 24, the areas Z305 at the four corners of the external shape may be rectangularly recessed.

Furthermore, as shown by lens 131'''''' in the lower right of Figure 24, the effective area 131a may be rectangular, and the outer periphery of the non-effective area 131b may be circular.

In other words, the sharper the corners of lens 131 are, the more likely they are to peel off from glass substrate 12, which may have adverse optical effects. Therefore, as shown by lenses 131' to 131''''' in Figure 24, by giving the corners a polygonal shape with an angle less than 90 degrees, a rounded shape, a shape with a concave or convex portion, or the like, lens 131 is configured to be less likely to peel off from glass substrate 12, and the risk of adverse optical effects can be reduced.

<Modifications of the lens end structure>
In the above, an example has been described in which the end of the lens 131 is formed perpendicular to the imaging surface of the solid-state imaging element 11. However, the lens 131 may be formed in another shape as long as the size of the lens 131 is set smaller than the size of the solid-state imaging element 11, an effective area 131a is set in the center of the lens 131, and a non-effective area 131b is set on the outer periphery thereof.

That is, as shown in the upper left of Figure 25, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens may be extended, and the end may be formed vertically, as shown by end Z331 of the non-effective area 131b (corresponding to the configuration in Figure 23).

Furthermore, as shown in the second upper part from the left in Figure 25, at the boundary between the non-effective area 131b and the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens may be extended, and the end may be formed into a tapered shape, as shown by end Z332 of the non-effective area 131b.

Furthermore, as shown in the third upper part from the left in Figure 25, at the boundary between the non-effective area 131b and the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens may be extended, and the end may be formed in a rounded shape, as shown by end Z333 of the non-effective area 131b.

Furthermore, as shown in the upper right part of Figure 25, at the boundary between the non-effective area 131b and the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens may be extended, and the end may be formed as a side surface with a multi-stage structure, as shown by end Z334 of the non-effective area 131b.

Furthermore, as shown in the lower left of Figure 25, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown at end Z335 of the non-effective area 131b, a bank-shaped protrusion is formed that has a horizontal flat portion at the end and protrudes further than the effective area 131a in a direction opposite to the direction of incidence of the incident light, and the side of the protrusion is formed vertically.

Furthermore, as shown in the second lower part from the left in Figure 25, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown by end Z336 of the non-effective area 131b, a bank-shaped protrusion is formed that has a horizontal flat portion at the end and protrudes further than the effective area 131a in a direction opposite to the direction of incidence of the incident light, and the side of the protrusion is formed in a tapered shape.

Furthermore, as shown in the third lower part from the left in Figure 25, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown by end Z337 of the non-effective area 131b, a bank-shaped protrusion is formed that has a horizontal flat portion at the end and protrudes further than the effective area 131a in a direction opposite to the direction of incidence of the incident light, and the side of the protrusion is formed in a rounded shape.

Furthermore, as shown in the lower right of Figure 25, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown at end Z338 of the non-effective area 131b, a bank-shaped protrusion having a horizontal flat portion at the end and protruding further than the effective area 131a in a direction opposite to the incident direction of the incident light is formed, and the side of the protrusion may be formed into a multi-step structure.

25 shows an example of a structure in which the end of the lens 131 has a horizontal flat portion and does not have a bank-shaped protrusion that protrudes in a direction opposite to the incident direction of the incident light beyond the effective area 131a, and the lower part shows an example of a structure in which the end of the lens 131 does not have a protrusion with a horizontal flat portion. Also, the upper and lower parts of FIG. 25 show, from the left, an example in which the end of the lens 131 is configured perpendicular to the glass substrate 12, an example in which the end is configured in a tapered shape, an example in which the end is configured in a rounded shape, and an example in which the end is configured in multiple stages with multiple side surfaces.

Furthermore, as shown in the upper part of Figure 26, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown at the end Z351 of the non-effective area 131b, a protrusion is formed perpendicular to the glass substrate 12, and further, a rectangular boundary structure Es may be left at the boundary with the glass substrate 12 on the solid-state imaging element 11.

Furthermore, as shown in the lower part of Figure 26, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown at the end Z352 of the non-effective area 131b, a protrusion is formed perpendicular to the glass substrate 12, and further, a round-shaped boundary structure Er may be left at the boundary with the glass substrate 12 on the solid-state imaging element 11.

In both the square-shaped boundary structure Es and the round-shaped boundary structure Er, by increasing the contact area between the lens 131 and the glass substrate 12, it is possible to bond the lens 131 and the glass substrate 12 more closely, and as a result, it is possible to prevent the lens 131 from peeling off from the glass substrate 12.

In addition, the square-shaped boundary structure Es and the round-shaped boundary structure Er may be used in any of the cases where the ends are formed in a tapered shape, a rounded shape, or a multi-stage structure.

Furthermore, as shown in FIG. 27, in the non-effective area 131b, at the boundary with the effective area 131a, a configuration similar to that of the effective area 131a as an aspheric lens is extended, and as shown by end Z371 of the non-effective area 131b, the side of the lens 131 is formed perpendicular to the glass substrate 12, and further, a refractive film 351 of a predetermined refractive index is formed on the glass substrate 12 at the outer periphery at approximately the same height as the lens 131.

As a result, for example, when the refractive index of the refractive film 351 is higher than a predetermined refractive index, as shown by the solid arrow at the top of Fig. 27, if there is incident light from the outer periphery of the lens 131, it is reflected to the outside of the lens 131 and, as shown by the dotted arrow, the incident light to the side of the lens 131 is reduced. As a result, the intrusion of stray light into the lens 131 is suppressed, thereby suppressing the occurrence of flare and ghosting.

Furthermore, when the refractive index of the refractive film 351 is lower than a predetermined refractive index, it transmits light that does not enter the incident surface of the solid-state imaging element 11 and attempts to pass out of the lens 131 from the side of the lens 131, as shown by the solid arrow at the bottom of Fig. 27, and reduces reflected light from the side of the lens 131, as shown by the dotted arrow. As a result, it is possible to suppress the intrusion of stray light into the lens 131, thereby suppressing the occurrence of flare and ghosts.

Furthermore, in Figure 27, an example has been described in which the refractive film 351 is formed at the same height as the lens 131 on the glass substrate 12 and has vertical ends, but it may have other shapes.

For example, as shown in region Z391 in the upper left of Figure 28, the refractive film 351 may be configured to have a tapered shape at its end on the glass substrate 12 and to have a thickness greater than the height of the end of the lens 131.

In addition, for example, as shown in region Z392 in the upper center of Figure 28, the refractive film 351 may be configured to have a tapered shape at the end and to have a thickness that is higher than the height of the end of the lens 131, and further configured so that a portion of it overlaps the non-effective region 131b of the lens 131.

Furthermore, for example, as shown in region Z393 in the upper right corner of Figure 28, the refractive film 351 may be configured to form a tapered shape from the height of the end of the lens 131 to the end of the glass substrate 12.

In addition, for example, as shown in area Z394 in the lower left of Figure 28, the refractive film 351 may be configured to have a tapered shape at the end of the glass substrate 12 and to have a thickness that is less than the height of the end of the lens 131.

Furthermore, for example, as shown in region Z395 in the lower right of Figure 28, the refractive film 351 may be configured to be concave toward the glass substrate 12 greater than the height of the end of the lens 131 and to be formed in a rounded shape.

In either of the configurations shown in Figures 27 and 28, the intrusion of stray light into lens 131 is suppressed, thereby making it possible to suppress the occurrence of flare and ghosting.

<16. Sixteenth embodiment>
In the above, examples have been described in which flare and ghosting are reduced by configuring the lens 131 so that it is difficult to peel off from the glass substrate 12 and by configuring the lens 131 to suppress the intrusion of stray light. However, flare and ghosting may also be reduced by configuring the lens 131 to suppress burrs of adhesive that occur during processing.

That is, as shown in the upper part of Fig. 29, consider a configuration in which an IRCF 14 is formed on a solid-state imaging element 11, and a glass substrate 12 is bonded to the IRCF 14 with adhesive 15 (for example, the configuration of the seventh embodiment in Fig. 15). Note that the configuration in Fig. 29 corresponds to the configuration other than the lens in the integrated component 10 in the imaging device 1 in Fig. 15.

In this case, a certain thickness of IRCF14 is required, but it is generally difficult to increase the viscosity of the IRCF14 material, and it is not possible to achieve the desired thickness in one go. However, applying multiple coats of IRCF14 can result in the generation of microvoids and bubbles, which can degrade the optical properties.

In addition, after the IRCF 14 is formed on the solid-state imaging element 11, the glass substrate 12 is bonded with adhesive 15, but warping occurs due to the hardening and shrinkage of the IRCF 14, which may cause poor bonding between the glass substrate 12 and the IRCF 14. Furthermore, the glass substrate 12 alone cannot suppress the warping of the IRCF 14, and warping may occur in the entire device, degrading the optical characteristics.

Furthermore, particularly when the glass substrate 12 and the IRCF 14 are joined via adhesive 15, resin burrs caused by the adhesive 15 may be generated during singulation, as shown in the upper range Z411 of Figure 29, which may reduce the machining accuracy during implementation, such as pick-up.

Therefore, as shown in the center of Figure 29, IRCF 14 is divided into two parts, IRCF 14-1 and 14-2, and IRCF 14-1 and 14-2 are bonded together with adhesive 15.

With this configuration, when forming IRCFs 14-1 and 14-2, it is possible to form thin films separately for each, making it easy to form thick films (division formation) to obtain the desired spectral characteristics.

In addition, when the glass substrate 12 is bonded to the solid-state imaging element 11, any steps on the solid-state imaging element 11 (sensor steps such as PADs) can be flattened and bonded using IRCF 14-2, making it possible to thin the adhesive 15 and, as a result, making it possible to reduce the height of the imaging device 1.

Furthermore, the IRCFs 14-1 and 14-2 formed on the glass substrate 12 and the solid-state imaging element 11, respectively, offset the warping, making it possible to reduce the warping of the device chip.

In addition, the elastic modulus of glass is higher than that of IRCFs 14-1 and 14-2. By making the elastic modulus of IRCFs 14-1 and 14-2 higher than that of adhesive 15, the top and bottom of the low-elasticity adhesive 15 are covered with IRCFs 14-1 and 14-2, which have a higher elastic modulus than adhesive 15, during singulation, making it possible to suppress the occurrence of resin burrs during singulation (Expand), as shown in range Z412 at the top of Figure 29.

Furthermore, as shown in the lower part of Figure 29, IRCFs 14'-1 and 14'-2 with adhesive properties may be formed and directly bonded to each other so that they face each other. In this way, it is possible to prevent the occurrence of resin burrs in the adhesive 15 that occur during singulation.

<Production Method>
Next, with reference to FIG. 30, a manufacturing method for bonding a glass substrate 12 to the solid-state imaging element 11 shown in the center of FIG. 29 with an adhesive 15 sandwiched between IRCFs 14-1 and 14-2 will be described.

In the first process, as shown in the upper left of Figure 30, IRCF 14-1 is applied to and formed on the glass substrate 12. Also, IRCF 14-2 is applied to and formed on the solid-state imaging element 11. Note that in the upper left of Figure 30, the glass substrate 12 is depicted in an inverted state after IRCF 14-2 has been applied to and formed.

In the second step, adhesive 15 is applied onto IRCF 14-2, as shown in the upper center of Figure 30.

In the third step, as shown in the upper right part of Figure 30, the IRCF 14-1 of the glass substrate 12 is bonded to the adhesive 15 shown in the upper center of Figure 30 so that it faces the surface to which the adhesive 15 is applied.

In the fourth step, an electrode is formed on the back side of the solid-state imaging element 11, as shown in the lower left of Figure 30.

In the fifth step, as shown in the lower center of Figure 30, the glass substrate 12 is thinned by polishing.

Then, after the fifth process, the ends are cut off with a blade or the like to separate the substrate, and IRCFs 14-1 and 14-2 are stacked on the imaging surface, with a glass substrate 12 formed on top to complete the solid-state imaging element 11.

Through the above process, the adhesive 15 is sandwiched between the IRCFs 14-1 and 14-2, making it possible to suppress the generation of burrs that accompany singulation.

In addition, IRCF14-1 and 14-2 can be formed to half the required film thickness, making it possible to reduce the thickness required for recoating or to eliminate the need for recoating, thereby suppressing the occurrence of microvoids and bubbles and reducing deterioration of optical properties.

Furthermore, since the film thickness of each of IRCFs 14-1 and 14-2 is reduced, it is possible to reduce warping due to curing shrinkage, which makes it possible to suppress the occurrence of poor bonding between the glass substrate 12 and IRCF 14, and makes it possible to suppress deterioration of optical characteristics due to warping.

In addition, as shown in the lower part of Figure 29, when IRCF 14'-1, 14'-2 with adhesive function are used, the process of applying adhesive 15 is simply omitted, so the explanation will be omitted.

<Modification of Side Shape After Slicing>
The above-described manufacturing method forms IRCFs 14-1 and 14-2, and when the solid-state imaging element 11 having the glass substrate 12 formed thereon is separated into individual pieces, it is assumed that the end portions are cut with a blade or the like so that the side cross section is perpendicular to the imaging surface.

However, by adjusting the shape of the side cross section of IRCFs 14-1, 14-2 and glass substrate 12 formed on the solid-state imaging element 11, the effects of fallen debris caused by glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15 may be further reduced.

For example, as shown in the upper left of Figure 31, the side cross section may be formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, and the glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15 are all equal and smaller than the solid-state imaging element 11.

Furthermore, as shown in the upper right part of Figure 31, the side cross section may be formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, the outer shapes of IRCFs 14-1, 14-2 and adhesive 15 are equal and are the second largest after the solid-state imaging element 11, and the outer shape of the glass substrate 12 is the smallest.

Also, as shown in the lower left of Figure 31, a side cross section may be formed so that the horizontal external shapes are, in order of size, solid-state imaging element 11, IRCFs 14-1 and 14-2, adhesive 15, and glass substrate 12.

Furthermore, as shown in the lower right of Figure 31, the side cross section may be formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, followed by the outer shape of the glass substrate 12, and the outer shapes of IRCFs 14-1, 14-2 and adhesive 15 are equal and smallest.

<Singulation method shown in the upper left of FIG. 31>
Next, the singulation method shown in the upper left corner of FIG. 31 will be described with reference to FIG.

The upper part of Figure 32 shows a diagram explaining the side cross section shown in the upper left of Figure 31. That is, in the upper part of Figure 32, the horizontal outer shape of the solid-state imaging element 11 is the largest, followed by the glass substrate 12, the IRCFs 14-1 and 14-2, and the adhesive 15, all of which are equally large and smaller than the solid-state imaging element 11.

Here, a method for forming the side cross section shown in the upper left of Fig. 31 will be described with reference to the middle part of Fig. 32. The middle part of Fig. 32 is an enlarged side view of the boundary between adjacent solid-state imaging elements 11 that are cut by individualization.

In the first step, at the boundary between adjacent solid-state imaging elements 11, a blade of a predetermined width Wb (e.g., approximately 100 μm) is used to cut an area Zb consisting of the glass substrate 12, IRCFs 14-1, 14-2 and adhesive 15 from the surface of IRCF 14-1 to a depth Lc1.

32, the position of depth Lc from the surface of IRCF14-1 is the surface of the solid-state imaging element 11, and is set to a position up to the wiring layer 11M formed by CuCu bonding or the like, but it is sufficient if it reaches the surface of the solid-state imaging element 11. Therefore, depth Lc1 may be cut down to the surface of the semiconductor substrate 81 in FIG. 6.

32, the blade is cut into the boundary while being centered at the center position of the adjacent solid-state imaging elements 11, as shown by the dashed line. In the figure, width WLA is the width at which the wiring layer is formed at the ends of two adjacent solid-state imaging elements 11. Furthermore, the width to the center of the scribe line of one chip of the solid-state imaging elements 11 is width Wc, and the width to the end of the glass substrate 12 is width Wg.

Furthermore, the range Zb corresponds to the shape of the blade, with the upper portion being the width Wb of the blade and the lower portion being represented as a hemispherical shape, which corresponds to the shape of the blade.

In the second step, for example, the Si substrate (semiconductor substrate 81 in FIG. 6) of the solid-state imaging element 11 is cut by dry etching, laser dicing, or a blade into a range Zh having a predetermined width Wd (e.g., about 35 μm) thinner than the blade that cut into the glass substrate 12, thereby dividing the solid-state imaging element 11 into individual pieces. However, in the case of laser dicing, the width Wd is approximately zero. The cut shape can also be adjusted to the desired shape by dry etching, laser dicing, or a blade.

As a result, as shown in the lower part of Figure 32, the side cross section is formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, and the glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15 are all equal and smaller than the solid-state imaging element 11.

In addition, in the lower part of Figure 32, as shown in range Z431, a portion of IRCF 14-2 in the horizontal direction near its boundary with the solid-state imaging element 11 is depicted as being wider than the horizontal width of IRCF 14-1, and differs from the shape of the side cross section of the glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15 in the upper part of Figure 32.

However, this is the result of deforming the cut shape made by a blade, and by adjusting the cut shape using dry etching, laser dicing, or a blade, the configuration in the lower part of Figure 32 can be made substantially identical to the configuration in the upper part of Figure 32.

In addition, the process of cutting the Si substrate (semiconductor substrate 81 in Figure 6) that forms the solid-state imaging element 11 using range Zh may be performed prior to the cutting operation in range Zb, and in this case, the operation may be performed in an upside-down state relative to the state shown in the middle of Figure 32.

Furthermore, since the wiring layer is prone to cracking and peeling during blade dicing, the range Zh may be cut by ablation processing using a short pulse laser.

<Singulation method in the upper right part of FIG. 31>
Next, the singulation method in the upper right part of FIG. 31 will be described with reference to FIG.

The upper part of Figure 33 shows a diagram explaining the side cross section shown in the upper right part of Figure 31. That is, the upper part of Figure 33 shows a side cross section formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, the outer shapes of IRCFs 14-1 and 14-2 and adhesive 15 are equal and are the second largest after the solid-state imaging element 11, and the outer shape of the glass substrate 12 is the smallest.

Here, a method for forming the side cross section shown in the upper right part of Fig. 31 will be described with reference to the middle part of Fig. 33. The middle part of Fig. 33 is an enlarged side view of the boundary between adjacent solid-state imaging elements 11 that are cut by individualization.

In the first step, a blade of a predetermined width Wb1 (e.g., approximately 100 μm) is used to cut an area Zb1 consisting of the glass substrate 12, IRCFs 14-1, 14-2 and adhesive 15 from the surface of IRCF 14-1 to a depth Lc11.

In the second step, a blade of a predetermined width Wb2 (<width Wb1) cuts a range Zb2 to a depth that exceeds the wiring layer 11M.

In the third step, for example, the Si substrate (semiconductor substrate 81 in FIG. 6) is cut by dry etching, laser dicing, or a blade to separate the solid-state imaging elements 11 into individual pieces by cutting a range Zh having a predetermined width Wd (e.g., about 35 μm) thinner than width Wb2. However, in the case of laser dicing, width Wd is approximately zero. In addition, the cut shape can be adjusted to the desired shape by dry etching, laser dicing, or a blade.

As a result, as shown in the lower part of Figure 33, the side cross section is formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, the outer shapes of IRCFs 14-1, 14-2 and adhesive 15 are equal and are the next largest after the solid-state imaging element 11, and the glass substrate 12 is the smallest.

In the lower part of Figure 33, as shown by range Z441, a portion of IRCF14-1 in the horizontal direction is drawn to be the same as the horizontal width of glass substrate 12. Also, as shown by range Z442, a portion of IRCF14-2 in the horizontal direction is drawn to be wider than the horizontal width of IRCF14-1.

Therefore, the cross-sectional side shapes of the glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15 in the lower part of Figure 33 are different from those in the upper part of Figure 33.

However, this is the result of deforming the cut shape made by a blade, and by adjusting the cut shape using dry etching, laser dicing, or a blade, the configuration in the lower part of Figure 32 can be made substantially identical to the configuration in the upper part of Figure 32.

In addition, the process of cutting the Si substrate (semiconductor substrate 81 in Figure 6) that forms the solid-state imaging element 11 using range Zh may be performed prior to the cutting operation of ranges Zb1 and Zb2, and in this case, the operation may be performed in a state inverted upside down relative to the state shown in the middle of Figure 33.

Furthermore, since the wiring layer is prone to cracking and peeling during blade dicing, the range Zh may be cut by ablation processing using a short pulse laser.

<Singulation method shown in the lower left of FIG. 31>
Next, the singulation method shown in the lower left corner of FIG. 31 will be described with reference to FIG.

The upper part of Figure 34 shows a diagram explaining the side cross section shown in the lower left part of Figure 31. That is, in the upper part of Figure 34, the side cross sections of the following are shown in order of size of outer shape: the horizontal outer shape of the solid-state imaging element 11, the IRCFs 14-1 and 14-2, the adhesive 15, and the glass substrate 12.

Here, a method for forming the side cross section shown in the upper right part of Fig. 31 will be described with reference to the middle part of Fig. 34. The middle part of Fig. 34 is an enlarged side view of the boundary between adjacent solid-state imaging elements 11 that are cut by individualization.

In the first step, a blade of a predetermined width Wb1 (e.g., approximately 100 μm) is used to cut the area Zb consisting of the glass substrate 12, IRCFs 14-1, 14-2 and adhesive 15 from the surface of IRCF 14-2 to a depth Lc21.

In the second step, laser ablation processing is performed to a predetermined width Wb2 (<width Wb1), and a range ZL is cut to a depth exceeding the wiring layer 11M.

In this process, IRCFs 14-1, 14-2 and adhesive 15 undergo thermal contraction near the processed surface due to absorption of the laser light, and due to wavelength dependence, adhesive 15 retreats relative to the cut surfaces of IRCFs 14-1, 14-2, resulting in a concave shape.

In the third step, for example, the Si substrate (semiconductor substrate 81 in FIG. 6) is cut by dry etching, laser dicing, or a blade to separate the solid-state imaging elements 11 into individual pieces by cutting a range Zh having a predetermined width Wd (e.g., about 35 μm) thinner than width Wb2. However, in the case of laser dicing, width Wd is approximately zero. In addition, the cut shape can be adjusted to the desired shape by dry etching, laser dicing, or a blade.

As a result, as shown in the lower part of Fig. 34, the side cross section is formed so that the external shape in the horizontal direction of the solid-state imaging element 11 is the largest, followed by the external shapes of the IRCFs 14-1 and 14-2, then the external shape of the adhesive 15, and the glass substrate 12 is the smallest. In other words, as shown by range Z452 in the lower part of Fig. 34, the external shape of the adhesive 15 is smaller than the external shapes of the IRCFs 14-1 and 14-2.

In the lower part of Figure 34, as shown by range Z453, a portion of IRCF14-2 in the horizontal direction is drawn wider than the horizontal width of IRCF14-1. Also, as shown by range Z451, a portion of IRCF14-1 in the horizontal direction is drawn the same as the horizontal width of glass substrate 12.

Therefore, the cross-sectional side shapes of the glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15 in the lower part of Figure 34 are different from those in the upper part of Figure 34.

However, this is the result of deforming the cut shape made by a blade, and by adjusting the cut shape using dry etching, laser dicing, or a blade, the configuration in the lower part of Figure 32 can be made substantially identical to the configuration in the upper part of Figure 32.

In addition, the process of cutting the Si substrate (semiconductor substrate 81 in Figure 6) that forms the solid-state imaging element 11 using range Zh may be performed prior to the cutting operation of ranges Zb and ZL, and in this case, the operation may be performed in an upside-down state relative to the state shown in the middle of Figure 34.

Furthermore, since the wiring layer is prone to cracking and peeling during blade dicing, the range Zh may be cut by ablation processing using a short pulse laser.

<Singulation method shown in the lower right corner of FIG. 31>
Next, the singulation method shown in the lower right corner of FIG. 31 will be described with reference to FIG.

The upper part of Figure 35 shows a diagram explaining the side cross section shown in the lower right part of Figure 31. That is, the upper part of Figure 35 shows a side cross section in which the horizontal outer shape of the solid-state imaging element 11 is the largest, followed by the outer shape of the glass substrate 12, and the outer shapes of the IRCFs 14-1, 14-2 and adhesive 15 are equal and smallest.

Here, a method for forming the side cross section shown in the lower right of Fig. 31 will be described with reference to the middle part of Fig. 35. The middle part of Fig. 35 is an enlarged side view of the boundary between adjacent solid-state imaging elements 11 that are cut by individualization.

In the first step, the glass substrate 12 is cut into a range Zs1 in which the width Ld is essentially zero by a so-called stealth (laser) dicing process using a laser.

In the second step, laser ablation processing is performed over a predetermined width Wab, and a range ZL is cut to a depth that exceeds IRCFs 14-1, 14-2 and the wiring layer 11M in the solid-state imaging element 11.

In this process, the laser ablation process is adjusted so that the cut surfaces of IRCFs 14-1, 14-2, and adhesive 15 are identical.

In the third step, a range Zs2 with a width of approximately zero is cut by a so-called stealth (laser) dicing process using a laser, and the solid-state imaging element 11 is separated into individual pieces. At this time, organic matter generated by ablation is discharged to the outside through the grooves processed by stealth dicing.

As a result, as shown by ranges Z461 and Z462 in the lower part of Figure 35, the side cross section is formed so that the horizontal outer shape of the solid-state imaging element 11 is the largest, followed by the outer shape of the glass substrate 12, and the outer shapes of IRCFs 14-1, 14-2 and adhesive 15 are equal and smallest.

In addition, the order of the stealth dicing process for the glass substrate 12 and the stealth dicing process for the solid-state imaging element 11 may be reversed, in which case the work may be performed in an upside-down state relative to the state shown in the middle part of Figure 35.

<Adding an anti-reflective coating>
In the above, we have described an example in which IRCFs 14-1 and 14-2 are formed on a solid-state imaging element 11 by adhering them with an adhesive 15, as shown in the upper left corner of Figure 36, and then a glass substrate 12 is formed on IRCF 14-1, thereby suppressing the occurrence of burrs and suppressing a decrease in optical characteristics. However, it is also possible to form an additional film having an anti-reflection function.

That is, for example, as shown in the center left of Figure 36, an additional film 371 having an anti-reflection function may be formed on the glass substrate 12.

Furthermore, for example, as shown in the lower left of Figure 36, additional films 371-1 to 371-4 having anti-reflection function may be formed on the glass substrate 12, at the boundary between the glass substrate 12 and IRCF 14-1, at the boundary between IRCF 14-1 and adhesive 15, and at the boundary between adhesive 15 and IRCF 14-2.

In addition, as shown in the upper right, middle right, and lower right parts of Figure 36, any one of additional films 371-2, 371-4, and 371-3 having anti-reflection function may be formed, or a combination of these may be formed.

Furthermore, the additional films 371, 371-1 to 371-4 may be formed, for example, from a film having a function equivalent to the above-mentioned AR coating 271a or the anti-reflection treatment portion (moth eye) 291a.

These additional films 371, 371-1 to 371-4 prevent the incidence of unnecessary light, thereby suppressing the occurrence of ghosts and flares.

<Addition to the side>
In the above, we have described examples in which additional films 371-1 to 371-4 with anti-reflection function are formed on glass substrate 12, at the boundary between glass substrate 12 and IRCF 14-1, at the boundary between IRCF 14-1 and adhesive 15, and at the boundary between adhesive 15 and IRCF 14-2. However, additional films that function as anti-reflection films or light absorbing films may also be formed on the side portions.

That is, as shown in the left part of Figure 37, an additional film 381 functioning as an anti-reflection film or a light absorbing film may be formed on the entire side cross section of the glass substrate 12, IRCFs 14-1, 14-2, adhesive 15, and solid-state imaging element 11.

Furthermore, as shown in the right part of Figure 37, an additional film 381 functioning as an anti-reflection film or a light absorbing film, etc. may be formed only on the sides of the glass substrate 12, IRCFs 14-1, 14-2, and adhesive 15, excluding the sides of the solid-state imaging element 11.

In either case, an additional film 381 is provided on the side surfaces of the solid-state imaging element 11, the glass substrate 12, the IRCFs 14-1 and 14-2, and the adhesive 15, thereby preventing unnecessary light from entering the solid-state imaging element 11 and suppressing the occurrence of ghosts and flares.

<17. Seventeenth embodiment>
In the above, an example has been described in which falling-off debris and the occurrence of flare and ghosting are suppressed by adjusting the horizontal size relationships of the stacked solid-state imaging element 11, IRCF 14-1, adhesive 15, IRCF 14-2, and glass substrate 12. However, by specifying the shape of the lens, it is also possible to realize a lens that is small and lightweight and capable of high-resolution imaging.

For example, consider the case where a glass substrate 12 is formed on a solid-state imaging element 11, and a lens corresponding to lens 271 having AR coating 271a formed thereon is bonded (for example, integrated component 10 in imaging device 1 in FIG. 19). Note that the configuration of imaging device 1 may be other than that shown in FIG. 19. For example, the same applies if lens 131 in integrated component 10 in imaging device 1 in FIG. 9 is replaced with lens 271.

That is, as shown in Fig. 38, an aspheric concave lens 401 (corresponding to lens 271 in Fig. 19) is formed on the glass substrate 12 on the solid-state imaging element 11 in a concentric circle centered on the center of gravity position as viewed from above. In addition, an AR coating 402 (a film having a function equivalent to the above-mentioned AR coating 271a or anti-reflection processing part 291a) is formed on the surface of the lens 401 on which light is incident, and a protrusion 401a is formed on the outer periphery. Note that Figs. 38 and 39 show a configuration in which the solid-state imaging element 11, glass substrate 12, and lens 271 are extracted from the integrated component 10 in the imaging device 1 in Fig. 19.

Here, as shown in Fig. 39, the lens 401 has a cone-like shape that is aspheric and concave with the center of gravity as viewed from above. In Fig. 39, the upper right part of the figure shows the cross-sectional shape of the lens 401 in the direction indicated by the dotted line in the upper left of the figure, and the lower right part of the figure shows the cross-sectional shape of the lens 401 in the direction indicated by the solid line in the upper left of the figure.

In Figure 39, the range Ze of the lens 401 has a common aspheric curved structure in the upper right and lower right parts of Figure 39, and this shape forms an effective area on the imaging surface of the solid-state imaging element 11 that focuses incident light from above in the figure.

In addition, because the lens 401 is composed of an aspheric curved surface, the thickness changes depending on the distance from the center position in the direction perpendicular to the incident direction of light. More specifically, at the center position, the lens thickness is the thinnest thickness D, and the lens thickness at the position furthest from the center in the range Ze is the thickest thickness H. In addition, when the thickness of the glass substrate 12 is thickness Th, the thickest thickness H of the lens 401 is thicker than the thickness Th of the glass substrate 12, and the thinnest thickness D of the lens 401 is thinner than the thickness Th of the glass substrate 12.

In other words, by summarizing these relationships, by using a lens 401 and a glass substrate 12 that satisfy the relationship of thickness H > thickness Th > thickness D, it is possible to realize an imaging device 1 (integrated component 10) that is small and lightweight and capable of capturing images at high resolution.

In addition, by making the volume VG of the glass substrate 12 smaller than the volume VL of the lens 401, it is possible to form the lens volume most efficiently, thereby realizing an imaging device 1 that is small and lightweight and capable of capturing images at high resolution.

<Stress distribution occurring when AR coating is heated>
Moreover, with the above-described configuration, it is possible to suppress stress caused by expansion and contraction of the AR coating 402 during thermal load in mounting reflow and during reliability testing.

Figure 40 shows the stress distribution due to expansion and contraction of the AR coating 402 under reflow thermal load when the external shape of the lens 401 in Figure 39 is changed. Note that the stress distribution in Figure 40 shows a distribution of 1/2 and 1/4 of the total range in both the horizontal and vertical directions based on the center position of the lens 401 shown as range Zp in Figure 38.

The leftmost part of Figure 40 shows the stress distribution that occurs in the AR coating 402A when subjected to mounting reflow thermal load in a lens 401A that does not have a protrusion 401a.

The second from the left in Figure 40 shows the stress distribution that occurs in the AR coating 402B when subjected to mounting reflow thermal load in a lens 401B having a protrusion 401a as shown in Figure 39.

The third figure from the left in Figure 40 shows the stress distribution that occurs in the AR coating 402C during mounting reflow thermal load in lens 401C in which the height of the protrusion 401a shown in Figure 39 is made higher than in the case of Figure 39.

The fourth figure from the left in Figure 40 shows the stress distribution that occurs in the AR coating 402D during mounting reflow thermal load in a lens 401D in which the width of the protrusion 401a shown in Figure 39 is larger than in the case of Figure 39.

The fifth figure from the left in Figure 40 shows the stress distribution that occurs in the AR coating 402E during mounting reflow thermal load in a lens 401E in which the taper on the side of the outer periphery of the protrusion 401a shown in Figure 39 is larger than in the case of Figure 39.

The rightmost part of Figure 40 shows the stress distribution that occurs in the AR coating 402F during mounting reflow thermal load in a lens 401F in which the protrusions 401a shown in Figure 39 are provided only on the four sides that form the outer periphery.

As shown in Figure 40, in the stress distribution generated in the AR coating 402A of lens 401A which does not have the protrusion 401a shown in the leftmost part, a large stress distribution is observed on the outer periphery of the effective area, but in the AR coatings 402B to 402F of lenses 401B to 401F which have the protrusion 401a formed, there is not a stress distribution as large as that seen in the AR coating 402A.

In other words, by providing a protrusion 401a on the lens 401, it is possible to suppress the occurrence of cracks in the AR coating 402 due to expansion and contraction of the lens 401 during mounting reflow thermal load.

<Modifications of Lens Shape>
In the above, an example has been described in which an imaging device 1 that is small and lightweight and capable of capturing images at high resolution is configured using a concave lens 401 with a protruding portion 401a tapered on the outer periphery as shown in Fig. 39. However, the shape of the lens 401 may be other shapes as long as the thicknesses D, H, and Th of the lens 401 and the glass substrate 12 satisfy the relationship of thickness H>thickness Th>thickness D. It is also more preferable if the volumes VG and VL satisfy the relationship of volume VG<volume VL.

For example, as shown in lens 401G in Figure 41, the side surface on the outer periphery of the protrusion 401a may be configured to be perpendicular to the glass substrate 12 and not include a taper.

In addition, as shown by lens 401H in Figure 41, the side surface on the outer periphery side of the protrusion 401a may be configured to include a rounded taper.

Furthermore, as shown by lens 401I in Figure 41, the lens may not include the protrusion 401a itself, and the side surface may include a linear tapered shape that forms a predetermined angle with respect to the glass substrate 12.

In addition, as shown by lens 401J in Figure 41, the lens may not include the protrusion 401a itself, and the side surface may be configured to be perpendicular to the glass substrate 12, and may not include a tapered shape.

Furthermore, as shown by lens 401K in Figure 41, the lens may not include the protrusion 401a itself, and the side surface may be configured to include a rounded tapered shape relative to the glass substrate 12.

As shown in lens 401L in Fig. 41, the side of the lens may have a two-stage configuration with two inflection points without including the protrusion 401a itself. The detailed configuration of lens 401L will be described later with reference to Fig. 42. Since the side of lens 401L has a two-stage configuration with two inflection points, it will be referred to as a two-stage side lens hereinafter.

Furthermore, as shown in lens 401M in Figure 41, the side may include a protrusion 401a and have a two-stage configuration with two inflection points on the outer side.

Furthermore, as shown by lens 401N in Figure 41, it may include a protrusion 401a, and the side surface may be configured to be perpendicular to the glass substrate 12, and a rectangular skirt portion 401b may be added near the boundary with the glass substrate 12.

Furthermore, as shown by lens 401N in Figure 41, it may include a protrusion 401a and be configured to be perpendicular to the glass substrate 12, and further include a rounded hem portion 401b' near the boundary with the glass substrate 12.

<Detailed configuration of two-stage side-type lens>
Now, with reference to FIG. 42, a detailed configuration of the two-stage side lens 401L in FIG. 41 will be described.

Figure 42 shows perspective views of the appearance of a solid-state imaging element 11 with a glass substrate 12 and a two-stage side lens 401L formed thereon, as viewed from various directions. Here, in the upper center of Figure 42, sides LA, LB, LC, and LD are set clockwise from the right side of the solid-state imaging element 11 in the figure.

The right part of Fig. 42 shows a perspective view of the periphery of the corners of sides LA and LB of the solid-state imaging element 11 when the solid-state imaging element 11 and the lens 401L are viewed from the line of sight E1 direction in the upper center of Fig. 42. The lower center part of Fig. 42 shows a perspective view of the periphery of the corners of sides LA and LB of the solid-state imaging element 11 when the solid-state imaging element 11 and the lens 401L are viewed from the line of sight E2 direction in the upper center of Fig. 42. Furthermore, the left part of Fig. 42 shows a perspective view of the periphery of the corners of sides LB and LC of the solid-state imaging element 11 when the solid-state imaging element 11 and the lens 401L are viewed from the line of sight E3 direction in the center of Fig. 42.

That is, in the two-stage side lens 401L, the center of the long sides LB and LD (not shown) is close to the center of gravity of a circle that functions as a lens with the thinnest lens thickness when viewed from the top surface of the two-stage side lens 401L, which is a concave lens, so that the lens becomes thin and the ridge line has a gently curved shape as surrounded by a dotted line.

In contrast, the centers of the short sides LA and LC are located far from the center of gravity, so the lens is made thicker and the ridges are made straight.

<Two inflection points and two-stage side>
As shown in FIG. 43, in the cross-sectional shape of the two-stage side lens 401L, the side surface of the non-effective area provided outside the effective area Ze is configured in two stages, and the average surfaces X1, X2 of the respective side surfaces are formed offset, with inflection points P1, P2 in the cross-sectional shape being formed at positions where a step is created by the two stages of the side surface.

The inflection points P1 and P2 change in the order of concave and convex, starting from the position closest to the solid-state imaging element 11.

In addition, the heights of the inflection points P1 and P2 from the glass substrate 12 are both located at positions higher than the thinnest thickness Th of the two-stage side lens 401L.

Furthermore, it is desirable that the difference between the average surfaces X1, X2 of the two side surfaces (the distance between the average surfaces X1, X2) be greater than the thickness of the solid-state imaging element 11 (the thickness of the silicon substrate 81 of the solid-state imaging element 11 in Figure 6).

In addition, it is desirable that the difference in distance between the average surfaces X1, X2 of the two side surfaces be 1% or more of the area width perpendicular to the incident direction of the incident light in the effective area of lens 401L (for example, the horizontal width He or the vertical height Ve in Figure 23).

Therefore, as long as two-stage side surfaces and two inflection points that satisfy the above-mentioned conditions are formed, the lens may have a shape other than that of the two-stage side surface lens 401L. For example, as shown in the second row from the top of Figure 43, the lens may be a two-stage side surface lens 401P in which two-stage side surfaces consisting of average surfaces X11 and X12 are provided and inflection points P11 and P12 with curvatures different from inflection points P1 and P2 are formed at a position higher from the glass substrate 12 than the thinnest thickness Th of the lens.

For example, as shown in the third row from the top of Figure 43, a two-stage side lens 401Q may be provided with two side stages consisting of average surfaces X21 and X22, and inflection points P21 and P22 with curvatures different from inflection points P1, P2 and P11, P22 are formed at a position higher from the glass substrate 12 than the thinnest thickness Th of the lens.

Furthermore, for example, as shown in the fourth row from the top of Figure 43, a two-stage side surface consisting of average surfaces X31 and X32 may be provided, inflection points P31 and P32 are formed at a position higher than the thinnest thickness Th of the lens from the glass substrate 12, and the end of the thickest position of the lens 401 may be rounded, forming a two-stage side surface type lens 401R.

<Stress distribution occurring when the AR coating is heated in a lens with two inflection points and two-stage side surfaces>
As described above, in the case of a two-stage side-type lens 401L having two inflection points and two-stage side surfaces, the stress applied to the AR coating 402 due to the expansion and contraction of the lens 401L during mounting reflow thermal load and reliability testing can be suppressed.

Figure 44 shows the stress distribution due to expansion and contraction of the AR coating 402 under mounting reflow thermal load when the external shape of the lens 401 in Figure 39 is changed. In Figure 44, the upper row shows the stress distribution of the AR coating 402 on the rear side when the lens 401 is viewed diagonally, and the lower row shows the stress distribution of the AR coating 402 on the front side when the lens 401 is viewed diagonally.

The leftmost part of Figure 44 shows the stress distribution that occurs in the AR coating 402S during mounting reflow thermal load for lens 401S (corresponding to lens 401A), which does not have a protrusion 401a and is not a two-stage side lens.

The second from the left in Figure 44 shows the stress distribution that occurs in the AR coating 402T during mounting reflow thermal load in a lens 401T corresponding to the two-stage side lens 401L shown in Figure 43.

The third figure from the left in Figure 44 shows the stress distribution that occurs in the AR coating 402U during mounting reflow thermal load for a lens 401U that does not have a protrusion 401a but has a tapered shape and the corners of each side of the lens are molded into a rounded shape.

The fourth figure from the left in Figure 44 shows the stress distribution that occurs in the AR coating 402V during mounting reflow thermal load for a lens 401V that has no protrusion 401a or tapered shape, has side surfaces perpendicular to the glass substrate 12, and has rounded corners on each side of the lens.

In addition, Fig. 45 shows graphs of the maximum value of the entire stress distribution (Worst), the maximum value of the effective area of the lens (Effective), and the maximum value at the ridgeline (Ridgeline) in the AR coating for each lens shape in Fig. 44, from the left. Also, the graphs of the maximum values in Fig. 45 show the maximum values of the stress distribution for AR coatings 402S to 402V, from the left.

As shown in Figure 45, the overall maximum stress of each lens is 1390 MPa at the corner Ws (Figure 44) of the upper surface for AR coating 402S of lens 401S, 1130 MPa at the corner Wt (Figure 44) of the ridge for AR coating 402T of lens 401T, 800 MPa at the ridge Wu (Figure 44) for AR coating 402U of lens 401U, and 1230 MPa at the ridge Wv (Figure 44) for AR coating 402V of lens 401V.

In addition, the maximum stress in the effective area of each lens is, as shown in Figure 45, 646 MPa for AR coating 402S on lens 401S, 588 MPa for AR coating 402T on lens 401T, 690 MPa for AR coating 402U on lens 401U, and 656 MPa for AR coating 402V on lens 401V.

Furthermore, the maximum stress at the ridge of each lens is 1050 MPa for AR coating 402S on lens 401S, 950 MPa for AR coating 402T on lens 401T, 800 MPa for AR coating 402U on lens 401U, and 1230 MPa for AR coating 402U on lens 401V.

According to Figure 45, the AR coating 402S of lens 401S has the smallest maximum stress in all cases, but according to Figure 44, in the overall stress distribution in the effective area of AR coating 402T of lens 401T, there is no stress distribution of around 600 MPa, which is prevalent in the area close to the outer periphery of AR coating 402U of lens 401U, and it can be seen that, overall, in the external shape consisting of AR coating 402T of lens 401T (same as AR coating 402L), the stress distribution generated in AR coating 402T of AR coating 402T (same as AR coating 402L) is small.

In other words, according to Figures 44 and 45, during mounting reflow thermal load, in the lens 401T (401L) having two inflection points and a two-stage side surface, the expansion and contraction occurring in the AR coating 402T (402L) is suppressed, and the stress caused by the expansion and contraction is reduced.

As described above, by adopting a two-stage side-type lens 401L having two inflection points and two-stage side faces as the lens 401, it is possible to suppress expansion and contraction due to heat during mounting reflow thermal load, reliability testing, etc.

As a result, it becomes possible to reduce the stress generated in the AR coating 402L, and to suppress the occurrence of cracks, lens peeling, etc. In addition, it becomes possible to suppress the expansion and contraction of the lens itself, which reduces the occurrence of distortion and suppresses the deterioration of image quality due to an increase in birefringence caused by distortion, and the occurrence of flare due to an increase in interfacial reflection caused by a local change in the refractive index.

<18. Eighteenth embodiment>
The above describes an example in which a lens that is small, lightweight, and capable of capturing high-resolution images is realized by specifying the shape of the lens. However, it is also possible to realize a lens that is even smaller, lighter, and capable of capturing high-resolution images by improving the precision with which the lens is formed on the solid-state imaging element 11.

As shown in the upper part of Figure 46, with the mold 452 pressed against the glass substrate 12 on the solid-state imaging element 11, the space between the mold 452 and the glass substrate 12 is filled with ultraviolet light curing resin 461, which is the material for the lens 401, and exposed to ultraviolet light from the top of the figure for a predetermined period of time.

Both the substrate 451 and the mold 452 are made of a material that transmits ultraviolet light.

The molding die 452 has an aspheric convex structure corresponding to the shape of the concave lens 401, and a light-shielding film 453 is formed on the outer periphery. Depending on the angle of incidence of the ultraviolet light, a taper can be formed on the side of the lens 401, for example, at an angle θ as shown in Figure 46.

The ultraviolet light curing resin 461 that is the material of the lens 401 is hardened by being exposed to ultraviolet light for a predetermined period of time, and is formed into an aspheric concave lens as shown in the lower part of Figure 46, and is attached to the glass substrate 12.

After a predetermined time has elapsed while being irradiated with ultraviolet light, the ultraviolet light curable resin 461 hardens to form the lens 401, and after the lens 401 is formed, the molding die 452 is removed from the formed lens 401 (demolding).

At the boundary between the outer periphery of the lens 401 and the glass substrate 12, a portion of the ultraviolet light curable resin 461 seeps out from the mold 452, generating a seepage portion 461a. However, since the ultraviolet light is blocked from the seepage portion 461a by the light-shielding film 453, as shown in the range Zc in the enlarged view Zf, the seepage portion 461a of the ultraviolet light curable resin 461 remains uncured, and after demolding, it is cured by the ultraviolet light contained in natural light, remaining as a skirt portion 401d.

As a result, the lens 401 is formed as a concave lens by the molding die 452, and a tapered shape is formed on the side at the angle θ defined by the light-shielding film 453. In addition, a skirt portion 401d is formed on the outer periphery of the lens 401 at the boundary with the glass substrate 12, which makes it possible to more firmly adhere the lens 401 to the glass substrate 12.

As a result, it is possible to form lenses with high precision that are small, lightweight, and capable of capturing high-resolution images.

In the above, an example has been described in which the light-shielding film 453 is provided on the outer periphery of the lens 401 on the back side (lower side in the figure) of the substrate 451 with respect to the incident direction of the ultraviolet light, as shown in the upper left part of Fig. 47. However, the light-shielding film 453 may also be provided on the outer periphery of the lens 401 on the front side (upper side in the figure) of the substrate 451 with respect to the incident direction of the ultraviolet light, as shown in the upper right part of Fig. 47.

In addition, as shown in the second from the top left of Figure 47, instead of the substrate 451, a molding die 452' that is horizontally larger than the molding die 452 may be formed, and the light-shielding film 453 may be provided on the outer periphery of the lens 401 on the back side (lower side in the figure) with respect to the direction of incidence of the ultraviolet light.

Furthermore, the light-shielding film 453 may be provided on the outer periphery of the lens 401 on the front side (upper side in the figure) of the substrate 451 of the molding die 452' with respect to the incident direction of ultraviolet light, as shown in the second from the top on the right in Figure 47.

In addition, the light-shielding film 453 may be formed by integrating the substrate 451 and the mold 452 into a mold 452'' as shown in the third image from the top left of Figure 47, and may be provided on the outer periphery of the lens 401 on the back side (lower side in the figure) relative to the incident direction of the ultraviolet light.

Furthermore, the light-shielding film 453 may be provided on the outer periphery of the lens 401 on the front side (upper side in the figure) with respect to the incident direction of the ultraviolet light, by forming a molding die 452'' by integrating the substrate 451 and the molding die 452, as shown in the third image from the top on the right in Figure 47.

Furthermore, as shown in the lower left of Figure 47, in addition to the substrate 451 and the molding die 452, a molding die 452''' may be formed having a structure that defines a portion of the side surface, and a light-shielding film 453 may be formed on the outer periphery of the molding die 452''', on the back side relative to the direction of incidence of ultraviolet light.

46 and 47 omit the IRCF 14 and adhesive 15 from the integrated component 10 of the imaging device 1 in Fig. 9, but this is omitted for the sake of convenience, and they may of course be provided between the lens 401 (131) and the glass substrate 12. In the following, the explanation will be given using an example of a configuration in which the IRCF 14 and adhesive 15 are omitted from the imaging device 1 in Fig. 9, but in either case, the IRCF 14 and adhesive 15 may be provided between the lens 401 (131) and the glass substrate 12, for example.

<Method of forming two-stage side-face lens>
Next, a method for manufacturing the two-stage lens will be described.

The basic manufacturing method is the same as that for lenses that do not have the two-stage sidewall type described above.

That is, as shown in the left part of Fig. 48, a molding die 452 corresponding to the side shape of the two-stage side lens 401L is prepared for the substrate 451, and ultraviolet light curing resin 461 is placed on the glass substrate 12 on the solid-state imaging element 11. Note that Fig. 48 shows the configuration of only the right half of the side cross section of the molding die 452.

Next, as shown in the center of Figure 48, the ultraviolet light curing resin 461 on which the molding die 452 is placed is fixed so as to press it against the glass substrate 12, thereby filling the recess of the molding die 452 with the ultraviolet light curing resin 461, and ultraviolet light is irradiated from above in the figure for a predetermined period of time.

The ultraviolet light curing resin 461 hardens when exposed to ultraviolet light, forming a concave two-stage side lens 401 that corresponds to the molding die 452.

After the lens 401 is formed by exposure to ultraviolet light for a predetermined period of time, the molding die 452 is released as shown in the right part of Figure 48, and the lens 401 consisting of a two-stage side lens is completed.

Also, as shown in the left part of Figure 49, a part of the outer periphery of the molding die 452 that abuts against the glass substrate 12 may be cut, for example, a part below the height of the inflection point closest to the glass substrate 12, of the two inflection points in the cross-sectional shape of the side surface, and a light-shielding film 453 may be provided on the cut surface.

In this case, as shown in the second from the left in Figure 49, when ultraviolet light is irradiated from above in the figure for a predetermined time with ultraviolet light curable resin 461 filled in the recess of mold 452, the ultraviolet light is blocked in the lower part of light-shielding film 453, so curing does not proceed, and lens 401 remains in an incomplete state. However, the ultraviolet light curable resin 461 around the effective area in the figure exposed to ultraviolet light proceeds to cure and is formed into lens 401.

When the molding die 452 is released in this state, as shown in the third from the left in Figure 49, the lens 401 formed as a two-stage side lens has the outermost two-stage side that is closest to the glass substrate 12 remaining as an oozing portion 461a of uncured ultraviolet light curing resin 461.

Therefore, as shown in the right part of Figure 49, the angle and surface roughness of the side surface of the uncured ultraviolet light curable resin 461, which remains in the state of an oozing portion 461a, is controlled and ultraviolet light is irradiated separately to harden it.

By doing this, as shown in the upper part of Figure 50, it is possible to set the angles formed by the average planes X1 and X2 of the side surfaces of lens 401 to different angles, such as angles θ1 and θ2, respectively, with respect to the direction of incidence of the incident light.

Here, when the angles of the sides X1 and X2 are angles θ1 and θ2, respectively, by configuring them so that angle θ1 < angle θ2, it is possible to suppress the occurrence of side flare and also to prevent the completed lens 401 from peeling off from the glass substrate 12 when the molding die 452 is released.

It is also possible to configure the surface roughness ρ(X1), ρ(X2) of each of the sides X1, X2 to be different.

Here, by setting the surface roughness ρ(X1), ρ(X2) of each of the sides X1, X2 such that surface roughness ρ(X1) < surface roughness ρ(X2), it is possible to suppress the occurrence of side flare and also to prevent the completed lens 401 from peeling off from the glass substrate 12 when the molding die 452 is released.

In addition, by adjusting the shape of the seeping-out portion 461a of the ultraviolet light curing resin 461, it is also possible to form a skirt portion 401d as shown in the lower part of Figure 50. This makes it possible to fix the lens 401 more firmly to the glass substrate 12.

The angles θ1, θ2, surface roughness ρ(X1), ρ(X2), and formation of the skirting portion 401d can be set by the shape of the mold 452 even when the light-shielding film 453 shown in FIG. 48 is not used. However, when the mold 452 provided with the light-shielding film 453 is used as shown in FIG. 49, the seepage portion 461a of the ultraviolet light curing resin 461 left as an uncured portion in the initial irradiation of ultraviolet light can be adjusted later, so that the degree of freedom in setting the angles θ1, θ2, surface roughness ρ(X1), ρ(X2), and skirting portion 401d can be increased.

In either case, it becomes possible to form the lens 401 with high precision on the glass substrate 12 of the solid-state imaging element 11. In addition, it becomes possible to adjust the angles of the side surfaces X1 and X2 of the two-stage side surface type lens 401, the surface roughness ρ(X1) and ρ(X2), and the presence or absence of the skirt portion 401d, so that it is possible to suppress the occurrence of flare and ghosting and to form the lens 401 more firmly on the glass substrate 12.

<19. Nineteenth embodiment>
The above describes an example of forming the lens 401 on the glass substrate 12 on the solid-state imaging element 11 with high precision by a molding method. However, in order to form the lens 401 at an appropriate position on the glass substrate 12, an alignment mark may be formed on the glass substrate 12 and the lens 401 may be positioned based on the alignment mark, thereby forming the lens 401 on the glass substrate 12 with even higher precision.

That is, as shown in Fig. 51, an effective area Ze of the lens 401 (corresponding to the effective area 131a in Fig. 23) is provided from the center, a non-effective area Zn (corresponding to the non-effective area 131b in Fig. 23) is provided on the outer periphery thereof, an area Zg where the glass substrate 12 is exposed is provided on the outer periphery thereof, and an area Zsc where a scribe line is set is provided on the outermost periphery of the solid-state imaging element 11. In Fig. 51, a protrusion 401a is provided in the non-effective area Zn (corresponding to the non-effective area 131b in Fig. 23).

The width of each region has the following relationship: width of effective region Ze > width of non-effective region Zn > width of region Zg where glass substrate 12 is exposed > width of region Zsc where the scribe line is set.

The alignment mark 501 is formed in an area Zg on the glass substrate 12 where the glass substrate 12 is exposed. Therefore, the size of the alignment mark 501 is smaller than the area Zg, but it must be a size that can be recognized by the image for alignment.

Alignment may be achieved by forming an alignment mark 501 on the glass substrate 12, for example, at a position where the corner of the lens 401 should abut, and adjusting the corner of the lens in the molding die 452 to the position where the alignment mark 501 is provided, based on an image captured by an alignment camera.

<Example of alignment mark>
The alignment marks 501 are, for example, alignment marks 501A to 501K as shown in FIG.

That is, alignment marks 501A to 501C are square, alignment marks 501D and 501E are circular, alignment marks 501F to 501I are polygonal, and alignment marks 501J and 501K are multiple linear shapes.

<Example of providing alignment marks on glass substrate and molding die>
Furthermore, among the alignment marks 501A to 501K, the black and gray portions may be formed at positions corresponding to the outer periphery of the lens 401 on the molding die 452 and the area Zg on the glass substrate 12, and the positional relationship between the lens 401 and the glass substrate 12 may be aligned by checking, for example, based on an image captured by an alignment camera whether they are in a corresponding positional relationship.

That is, in the case of alignment mark 501A, as shown in FIG. 52, an alignment mark 501' consisting of a gray rectangular frame is provided on the molding die 452 so that the lens 401 and the molding die 452 are in the appropriate positional relationship, and an alignment mark 501 consisting of a rectangular portion that becomes the black portion is formed.

Then, the alignment mark 501 on the glass substrate 12 and the alignment mark 501' on the molding die 452 are imaged with an alignment camera from the direction of the arrow in Figure 53, and the alignment can be adjusted by adjusting the position of the molding die 452 so that the black directional alignment mark 501 is imaged so that it is contained within and overlaps the alignment mark 501' consisting of a gray rectangular frame.

In this case, it is desirable to arrange the alignment mark 501 in the black portion and the alignment mark 501' in the gray portion within the same field of view of the same camera, but it is also possible to calibrate the positional relationship between the multiple cameras in advance and align the multiple cameras based on the corresponding positional relationship between the alignment marks 501, 501' provided in corresponding different positions.

In either case, the alignment mark 501 makes it possible to position and form the lens 401 with high precision on the glass substrate 12 of the solid-state imaging element 11.

<20. Twentieth embodiment>
In the above, an example has been described in which the lens 401 and the glass substrate 12 on the solid-state imaging element 11 are positioned with high precision using alignment marks. However, it is also possible to form an AR coating 402 on the effective area of the lens 401 to improve sensitivity and realize high-definition imaging.

That is, for example, as shown by the thick line at the top of Figure 54, the AR coating 402-P1 may be formed over the entire area of the glass substrate 12, the non-effective area including the side and flat portion of the protrusion 401a (corresponding to the non-effective area 131b in Figure 23), and the effective area (corresponding to the effective area 131a in Figure 23).

Also, for example, as shown in the second from the top of Fig. 54, the AR coating 402-P2 may be formed only on the effective area within the protrusion 401a on the lens 401. By forming the AR coating 402-P2 only on the area (effective area (corresponding to the effective area 131a in Fig. 23)) within the protrusion 401a on the lens 401, it is possible to reduce stress caused by thermal expansion and contraction of the lens 401 during mounting reflow thermal load, etc., and to suppress the occurrence of cracks in the AR coating 402-P2.

Furthermore, for example, as shown in the third figure from the top in Figure 54, an AR coating 402-P3 may be formed in the inner region (effective region (corresponding to effective region 131a in Figure 23)) of protrusion 401a on lens 401, including the flat portion of protrusion 401a. By forming AR coating 402-P3 only in the inner region of protrusion 401a on lens 401, including protrusion 401a on lens 401, it is possible to reduce the stress generated in AR coating 402-P3 due to thermal expansion and contraction of lens 401 during mounting reflow thermal load, etc., and the occurrence of cracks can be suppressed.

Furthermore, for example, as shown in the fourth figure from the top in Figure 54, in addition to the planar portion of protrusion 401a on lens 401 and part of its outer periphery, AR coating 402-P4 may be formed in the inner region of protrusion 401a (effective region (corresponding to effective region 131a in Figure 23)), and AR coating 402-P5 may be formed in the region near the boundary between glass substrate 12 and lens 401 and glass substrate 12. By forming an area where an AR coating is not formed on part of the side portion of lens 401, as in AR coatings 402-P4 and 402-P5, it is possible to reduce the stress generated in AR coating 402-P2 due to thermal expansion and contraction of lens 401 during mounting reflow thermal load, etc., and to suppress the occurrence of cracks.

Figure 55 summarizes the stress distribution that occurs in the AR coating 402 when subjected to mounting reflow thermal load when the area on the lens 401 where the AR coating 402 is formed is changed in various ways.

Figure 55 shows, at the top, the external shape of the lens 401 and the AR coating 402 when the lens 401 is divided into two parts horizontally and vertically, and at the bottom, the stress distribution that occurs in the AR coating 402 when subjected to the corresponding mounting reflow thermal load.

The left part of Figure 55 shows the case where an AR coating 402AA is formed in which an AR coating is formed over the entire surface including the surrounding glass substrate 12, the side surface of the lens 401, the protrusion 401a, and the inside of the protrusion 401a.

The second from the left in Figure 55 shows the case of AR coating 402AB, in which, compared to the configuration in the leftmost part of Figure 55, no AR coating is formed on the surrounding glass substrate 12 and the sides of lens 401, and an AR coating is formed in the other areas.

The third from the left in Figure 55 is the case of AR coating 402AC, in which, compared to the configuration in the leftmost part of Figure 55, no AR coating is formed on the side area of lens 401, and AR coating is applied to the surrounding glass substrate 12, protrusion 401a, and the inside of protrusion 401a.

The fourth from the left in Fig. 55 shows the case of AR coating 402AD, in which, compared to the configuration in the leftmost part of Fig. 55, no AR coating is formed on the side region of lens 401, the flat portion of protrusion 401a, or the inside of protrusion 401a in the region from the flat portion of the top surface of protrusion 401a to a predetermined width A, and the AR coating is applied to the rest of the glass substrate 12 inside and around protrusion 401a. Here, width A is, for example, 100 μm.

The fifth from the left in Figure 55 is the case of AR coat 402AE, in which, compared to the configuration in the leftmost part of Figure 55, an AR coat is formed on the inside of protrusion 401a, the flat part on the top surface of protrusion 401a, and the outer side surface of protrusion 401a, in an area extending a predetermined width A below the flat part.

The sixth from the left in Figure 55 is the case of AR coat 402AF, in which, compared to the configuration in the leftmost part of Figure 55, an AR coat is formed on the inside of protrusion 401a, the flat part on the top surface of protrusion 401a, and the outer side surface of protrusion 401a, in an area extending a predetermined width 2A below the flat part.

The seventh from the left in Figure 55 is the case of AR coat 402AG, in which, compared to the configuration in the leftmost part of Figure 55, an AR coat is formed on the inside of protrusion 401a, the flat part on the top surface of protrusion 401a, and the outer side surface of protrusion 401a, in an area up to a predetermined width 3A below the flat part.

The eighth from the left in Figure 55 is the case of AR coat 402AH, in which, compared to the configuration in the leftmost part of Figure 55, an AR coat is formed on the inside of protrusion 401a, the flat part on the top surface of protrusion 401a, and the outer side surface of protrusion 401a, in an area extending a predetermined width 4A below the flat part.

A comparison with the leftmost part of Figure 55 shows that in either case, the stress generated in the AR coating 402 is smaller when the AR coating inside the protrusion 401a of the lens 401 is formed in a state where it is not continuously connected to the AR coating 402 on the glass substrate 12, than when the AR coating 402AA is formed to cover the entire surface of the lens 401.

As described above, by forming the AR coating 402 on the lens 401, it becomes possible to suppress the occurrence of flare and ghosting, and to capture higher resolution images.

In addition, the AR coating 402 is formed over the entire surface including the effective and non-effective areas of the lens 401 including the protrusion 401a, and on the glass substrate 12 which forms its periphery, by providing an area where the AR coating is not formed in at least a part other than the effective area and the glass substrate 12, it becomes possible to suppress the occurrence of cracks due to expansion and contraction caused by heating during mounting reflow thermal load or reliability testing, etc.

Note that although we have described the AR coating 402 here, other films may be used as long as they are formed on the surface of the lens 401, and this also applies to anti-reflection films such as moth-eye films.

Although the above has been described as an example of a lens with a protrusion 401a, even if the lens does not have a protrusion 401a, it is sufficient that an area where an AR coating is not formed is provided on at least a part of the entire surface including the effective area and the non-effective area and on the glass substrate 12 that is the outer periphery of the effective area and the glass substrate 12. In other words, it is sufficient that the AR coating 402 formed on the lens 401 is not formed in a state where it is continuously connected to the AR coating 402 formed on the lens side and the glass substrate 12. For this reason, the lens 401 may be, for example, a two-stage side type lens 401L, and the same effect is achieved if the AR coating 402 formed on the lens 401 is formed in a state where it is not continuously connected to the AR coating 402 formed on the lens side and the glass substrate 12.

<21. Twenty-first embodiment>
In the above, an example has been described in which the AR coating 402 formed on the lens 401 is not formed in a state in which it is continuously connected to the AR coating 402 formed on the glass substrate 12, thereby reducing the stress generated in the AR coating 402 due to expansion and contraction caused by heat during the mounting reflow thermal load.

However, a light-shielding film may be formed to cover the protrusion 401a and sides of the lens 401 to suppress the occurrence of side flare.

That is, as shown in the top row of Figure 56, a light-shielding film 521 may be formed on the glass substrate 12 over the entire range up to the height of the side surface of the lens 401 and the flat portion of the upper surface of the protrusion 401a, i.e., the range other than the effective area.

Also, as shown in the second from the top of Figure 56, a light-shielding film 521 may be formed on the entire surface from the glass substrate 12 to the side of the lens 401 and the flat portion of the upper surface of the protrusion 401a, i.e., on the entire surface other than the effective area.

Furthermore, as shown in the third figure from the top in Figure 56, a light-shielding film 521 may be formed on the side of the protrusion 401a of the lens 401 from above the glass substrate 12.

In addition, as shown in the fourth figure from the top in Figure 56, a light-shielding film 521 may be formed on the side of the protrusion 401a of the lens 401 in a range from above the glass substrate 12 to a predetermined height from the glass substrate 12.

Furthermore, as shown in the fifth figure from the top in Figure 56, a light-shielding film 521 may be formed only on the side surface of the protrusion 401a of the lens 401.

In addition, as shown in the sixth figure from the top in Figure 56, a light-shielding film 521 may be formed in the range up to the highest position of the two sides of the two-stage side lens 401 on the glass substrate 12.

Furthermore, as shown in the seventh image from the top of Figure 56, a light-shielding film 521 may be formed to cover the entire surface up to the highest position of the two sides of the two-stage side lens 401 on the glass substrate 12, and the outer periphery of the solid-state imaging element 11.

In any case, the light-shielding film 521 is formed by partial film deposition, by depositing a film and then performing lithography, by forming a resist and then depositing a film and lifting off the resist, or by using lithography.

In addition, a bank for forming a light-shielding film may be formed on the outer periphery of the two-stage side lens 401, and a light-shielding film 521 may be formed on the outer periphery of the two-stage side lens 401, inside the bank.

That is, as shown in the top row of Figure 57, a bank 531 of the same height as the lens height may be formed on the glass substrate 12 at the outer periphery of the double-sided lens 401, and a light-shielding film 521 may be formed by lithography or coating on the inside of the bank 531 at the outer periphery of the double-sided lens 401, and then the heights of the light-shielding film 521, the lens 401, and the bank 531 may be aligned by polishing using CMP (Chemical Mechanical Polishing) or the like.

Also, as shown in the second row of Figure 57, a bank 531 of the same height as the lens height can be formed on the glass substrate 12 at the outer periphery of the two-stage side lens 401, and the heights of the light-shielding film 521, lens 401, and bank 531 can be self-aligned by the material of the light-shielding film 521 simply by applying the material of the light-shielding film 521 to the inside of the bank 531 at the outer periphery of the two-stage side lens 401.

Furthermore, as shown in the third row of Figure 57, a bank 531 of the same height as the lens height may be formed on the glass substrate 12 at the outer periphery of the two-stage side lens 401, and a light-shielding film 521 may simply be formed by lithography on the inside of the bank 531 at the outer periphery of the two-stage side lens 401.

Also, as shown in the fourth row of Figure 57, a bank 531 may be formed on the glass substrate 12 at the outer periphery of the two-stage side lens 401 so as to connect the boundary between the two-stage side lens 401 and the glass substrate 12, and a light-shielding film 521 may be formed by lithography or coating on the inside of the bank 531 at the outer periphery of the two-stage side lens 401, and then the heights of the light-shielding film 521, the lens 401, and the bank 531 may be aligned by polishing using CMP (Chemical Mechanical Polishing) or the like.

Furthermore, as shown in the fifth row of Figure 57, a bank 531 is formed on the glass substrate 12 at the outer periphery of the two-stage side lens 401 so as to connect the boundary between the two-stage side lens 401 and the glass substrate 12, and the heights of the light-shielding film 521, the lens 401, and the bank 531 can be self-aligned by the material of the light-shielding film 521 simply by applying the material of the light-shielding film 521 to the inside of the bank 531 at the outer periphery of the two-stage side lens 401.

Furthermore, as shown in the sixth row of Figure 57, a bank 531 may be formed on the glass substrate 12 at the outer periphery of the two-stage side lens 401 so as to connect the boundary between the two-stage side lens 401 and the glass substrate 12, and a light-shielding film 521 may simply be formed by lithography on the outer periphery of the two-stage side lens 401, inside the bank 531.

In either case, a light-shielding film is formed to cover the protruding portion 401a and side surfaces of the lens 401, making it possible to suppress the occurrence of side flare.

In the above, we have described an example in which a light-shielding film is formed on the outer periphery of lens 401, but as long as light cannot enter from the outer periphery of lens 401, it is possible to form, for example, a light-absorbing film instead of the light-shielding film.

<22. Examples of application to electronic devices>
The imaging device 1 of Figures 1, 4, and 6 to 17 described above can be applied to various electronic devices, such as imaging devices such as digital still cameras and digital video cameras, mobile phones with an imaging function, and other devices with an imaging function.

Figure 58 is a block diagram showing an example configuration of an imaging device as an electronic device to which the present technology is applied.

The imaging device 1001 shown in Figure 58 is configured with an optical system 1002, a shutter device 1003, a solid-state imaging element 1004, a driving circuit 1005, a signal processing circuit 1006, a monitor 1007, and a memory 1008, and is capable of capturing still images and moving images.

The optical system 1002 is composed of one or more lenses and guides light (incident light) from the subject to the solid-state image sensor 1004, forming an image on the light receiving surface of the solid-state image sensor 1004.

The shutter device 1003 is disposed between the optical system 1002 and the solid-state imaging element 1004, and controls the light irradiation period and light blocking period to the solid-state imaging element 1004 according to the control of the drive circuit 1005.

The solid-state imaging element 1004 is configured by a package including the above-mentioned solid-state imaging element. The solid-state imaging element 1004 accumulates signal charge for a certain period of time in response to light that is imaged on the light receiving surface via the optical system 1002 and the shutter device 1003. The signal charge accumulated in the solid-state imaging element 1004 is transferred in accordance with a drive signal (timing signal) supplied from the drive circuit 1005.

The drive circuit 1005 outputs a drive signal that controls the transfer operation of the solid-state imaging element 1004 and the shutter operation of the shutter device 1003, thereby driving the solid-state imaging element 1004 and the shutter device 1003.

The signal processing circuit 1006 performs various signal processing on the signal charges output from the solid-state imaging element 1004. The image (image data) obtained by performing the signal processing by the signal processing circuit 1006 is supplied to a monitor 1007 for display, or is supplied to a memory 1008 for storage (recording).

Even in the imaging device 1001 configured in this manner, by applying any one of the imaging devices 1 shown in Figures 1, 9, and 11 to 22 instead of the above-mentioned optical system 1002 and solid-state imaging element 1004, it is possible to achieve a compact and low-profile device configuration while suppressing ghosts and flares caused by internal reflection.

<23. Examples of Use of Solid-State Imaging Device>
FIG. 59 is a diagram showing an example of using the imaging device 1 described above.

The imaging device 1 described above can be used in various cases, for example, to sense light such as visible light, infrared light, ultraviolet light, and X-rays, as follows:

- Devices that take images for viewing, such as digital cameras and mobile devices with camera functions; - Devices for traffic purposes, such as in-vehicle sensors that take images of the front and rear of a car, the surroundings, and the interior of the car for safe driving such as automatic stopping and for recognizing the driver's state, surveillance cameras that monitor moving vehicles and roads, and distance measuring sensors that measure the distance between vehicles, etc.; - Devices for home appliances such as TVs, refrigerators, and air conditioners that take images of users' gestures and operate devices in accordance with those gestures; - Devices for medical and healthcare purposes, such as endoscopes and devices that take images of blood vessels by receiving infrared light; - Devices for security purposes, such as surveillance cameras for crime prevention and cameras for person authentication; - Devices for beauty purposes, such as skin measuring devices that take images of the skin and microscopes that take images of the scalp; - Devices for sports, such as action cameras and wearable cameras for sports purposes, etc.; - Devices for agricultural purposes, such as cameras for monitoring the condition of fields and crops.

<24. Application example to endoscopic surgery system>
The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

Figure 60 is a diagram showing an example of the general configuration of an endoscopic surgery system to which the technology disclosed herein (the present technology) can be applied.

Figure 60 shows an operator (doctor) 11131 performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000. As shown in the figure, the endoscopic surgery system 11000 is composed of an endoscope 11100, other surgical tools 11110 such as an insufflation tube 11111 and an energy treatment tool 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are mounted.

The endoscope 11100 is composed of a lens barrel 11101, the tip of which is inserted into the body cavity of the patient 11132 at a predetermined length, and a camera head 11102 connected to the base end of the lens barrel 11101. In the illustrated example, the endoscope 11100 is configured as a so-called rigid lens barrel having a rigid lens barrel 11101, but the endoscope 11100 may be configured as a so-called flexible lens barrel having a flexible lens barrel.

An opening into which an objective lens is fitted is provided at the tip of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100, and light generated by the light source device 11203 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 11101, and is irradiated via the objective lens toward an object to be observed in the body cavity of the patient 11132. The endoscope 11100 may be a direct-viewing endoscope, an oblique-viewing endoscope, or a side-viewing endoscope.

An optical system and an image sensor are provided inside the camera head 11102, and the reflected light (observation light) from the observation object is focused on the image sensor by the optical system. The observation light is photoelectrically converted by the image sensor to generate an electrical signal corresponding to the observation light, i.e., an image signal corresponding to the observation image. The image signal is sent to the camera control unit (CCU: Camera Control Unit) 11201 as RAW data.

The CCU 11201 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and controls the overall operation of the endoscope 11100 and the display device 11202. Furthermore, the CCU 11201 receives an image signal from the camera head 11102, and performs various image processing on the image signal, such as development processing (demosaic processing), to display an image based on the image signal.

The display device 11202, under the control of the CCU 11201, displays an image based on an image signal that has been subjected to image processing by the CCU 11201.

The light source device 11203 is composed of a light source such as an LED (Light Emitting Diode) and supplies irradiation light to the endoscope 11100 when photographing the surgical site, etc.

The input device 11204 is an input interface for the endoscopic surgery system 11000. A user can input various information and instructions to the endoscopic surgery system 11000 via the input device 11204. For example, the user inputs an instruction to change the imaging conditions (type of irradiation light, magnification, focal length, etc.) of the endoscope 11100.

The treatment tool control device 11205 controls the operation of the energy treatment tool 11112 for cauterizing tissue, incising, sealing blood vessels, etc. The insufflation device 11206 sends gas into the body cavity of the patient 11132 via the insufflation tube 11111 to inflate the body cavity in order to ensure a clear field of view for the endoscope 11100 and to ensure a working space for the surgeon. The recorder 11207 is a device capable of recording various types of information related to surgery. The printer 11208 is a device capable of printing various types of information related to surgery in various formats such as text, images, or graphs.

The light source device 11203 that supplies irradiation light to the endoscope 11100 when photographing the surgical site can be composed of a white light source composed of, for example, an LED, a laser light source, or a combination of these. When the white light source is composed of a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high precision, so that the white balance of the captured image can be adjusted in the light source device 11203. In this case, it is also possible to capture images corresponding to each of the RGB colors in a time-division manner by irradiating the observation object with laser light from each of the RGB laser light sources in a time-division manner and controlling the drive of the image sensor of the camera head 11102 in synchronization with the irradiation timing. According to this method, a color image can be obtained without providing a color filter to the image sensor.

The light source device 11203 may be controlled to change the intensity of the light it outputs at predetermined time intervals. The driving of the image sensor of the camera head 11102 may be controlled in synchronization with the timing of the change in the light intensity to acquire images in a time-division manner, and the images may be synthesized to generate an image with a high dynamic range that is free of so-called blackout and whiteout.

The light source device 11203 may also be configured to supply light of a predetermined wavelength band corresponding to special light observation. In special light observation, for example, by utilizing the wavelength dependency of light absorption in body tissue, a narrow band of light is irradiated compared to the irradiation light (i.e., white light) during normal observation, a predetermined tissue such as blood vessels on the mucosal surface is photographed with high contrast, so-called narrow band imaging. Alternatively, in special light observation, fluorescence observation may be performed in which an image is obtained by fluorescence generated by irradiating excitation light. In fluorescence observation, excitation light is irradiated to body tissue and fluorescence from the body tissue is observed (autofluorescence observation), or a reagent such as indocyanine green (ICG) is locally injected into the body tissue and excitation light corresponding to the fluorescence wavelength of the reagent is irradiated to the body tissue to obtain a fluorescent image. The light source device 11203 may be configured to supply narrow band light and/or excitation light corresponding to such special light observation.

Figure 61 is a block diagram showing an example of the functional configuration of the camera head 11102 and CCU 11201 shown in Figure 60.

The camera head 11102 has a lens unit 11401, an imaging unit 11402, a drive unit 11403, a communication unit 11404, and a camera head control unit 11405. The CCU 11201 has a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera head 11102 and the CCU 11201 are connected to each other by a transmission cable 11400 so that they can communicate with each other.

The lens unit 11401 is an optical system provided at the connection with the lens barrel 11101. Observation light taken in from the tip of the lens barrel 11101 is guided to the camera head 11102 and enters the lens unit 11401. The lens unit 11401 is composed of a combination of multiple lenses including a zoom lens and a focus lens.

The imaging unit 11402 is composed of an imaging element. The imaging element constituting the imaging unit 11402 may be one (so-called single-plate type) or multiple (so-called multi-plate type). When the imaging unit 11402 is composed of a multi-plate type, for example, each imaging element may generate an image signal corresponding to each of RGB, and a color image may be obtained by combining them. Alternatively, the imaging unit 11402 may be configured to have a pair of imaging elements for acquiring image signals for the right eye and the left eye corresponding to 3D (Dimensional) display. By performing 3D display, the surgeon 11131 can more accurately grasp the depth of the biological tissue in the surgical site. In addition, when the imaging unit 11402 is composed of a multi-plate type, multiple lens units 11401 may be provided corresponding to each imaging element.

Furthermore, the imaging unit 11402 does not necessarily have to be provided in the camera head 11102. For example, the imaging unit 11402 may be provided inside the telescope tube 11101, immediately after the objective lens.

The driving unit 11403 is composed of an actuator, and moves the zoom lens and focus lens of the lens unit 11401 a predetermined distance along the optical axis under the control of the camera head control unit 11405. This allows the magnification and focus of the image captured by the imaging unit 11402 to be appropriately adjusted.

The communication unit 11404 is configured by a communication device for transmitting and receiving various information between the communication unit 11404 and the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 as RAW data to the CCU 11201 via the transmission cable 11400.

In addition, the communication unit 11404 receives a control signal for controlling the driving of the camera head 11102 from the CCU 11201, and supplies it to the camera head control unit 11405. The control signal includes information on the imaging conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value at the time of capturing the image, and/or information specifying the magnification and focus of the captured image.

The above-mentioned frame rate, exposure value, magnification, focus, and other imaging conditions may be appropriately specified by the user, or may be automatically set by the control unit 11413 of the CCU 11201 based on the acquired image signal. In the latter case, the endoscope 11100 is equipped with a so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function.

The camera head control unit 11405 controls the operation of the camera head 11102 based on a control signal from the CCU 11201 received via the communication unit 11404.

The communication unit 11411 is configured by a communication device for transmitting and receiving various information between the camera head 11102. The communication unit 11411 receives an image signal transmitted from the camera head 11102 via the transmission cable 11400.

In addition, the communication unit 11411 transmits a control signal to the camera head 11102 for controlling the driving of the camera head 11102. The image signal and the control signal can be transmitted by electrical communication, optical communication, etc.

The image processing unit 11412 performs various image processing on the image signal, which is RAW data transmitted from the camera head 11102.

The control unit 11413 performs various controls related to the imaging of the surgical site, etc. by the endoscope 11100, and the display of the captured images obtained by imaging the surgical site, etc. For example, the control unit 11413 generates a control signal for controlling the driving of the camera head 11102.

The control unit 11413 also displays the captured image showing the surgical site on the display device 11202 based on the image signal that has been image-processed by the image processing unit 11412. At this time, the control unit 11413 may recognize various objects in the captured image using various image recognition techniques. For example, the control unit 11413 can recognize surgical tools such as forceps, specific biological parts, bleeding, mist generated when using the energy treatment tool 11112, and the like, by detecting the shape and color of the edges of objects included in the captured image. When the control unit 11413 displays the captured image on the display device 11202, it may use the recognition result to superimpose various types of surgical support information on the image of the surgical site. By superimposing the surgical support information and presenting it to the surgeon 11131, the burden on the surgeon 11131 can be reduced and the surgeon 11131 can proceed with the surgery reliably.

The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable corresponding to communication of electrical signals, an optical fiber corresponding to optical communication, or a composite cable of these.

In the illustrated example, communication is performed wired using a transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may also be performed wirelessly.

An example of an endoscopic surgery system to which the technology of the present disclosure can be applied has been described above. The technology of the present disclosure can be applied to, for example, the endoscope 11100, the camera head 11102 (the imaging unit 11402), the CCU 11201 (the image processing unit 11412), etc., among the configurations described above. Specifically, for example, the imaging device 1 of Figures 1, 9, and 11 to 22 can be applied to the lens unit 11401 and the imaging unit 10402. By applying the technology of the present disclosure to the lens unit 11401 and the imaging unit 10402, it is possible to realize a compact and low-profile device configuration and suppress the occurrence of flare and ghosts caused by internal reflection.

Note that, although an endoscopic surgery system has been described here as an example, the technology disclosed herein may also be applied to other systems, such as microsurgical systems.

<25. Examples of applications to moving objects>
The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of moving body such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an airplane, a drone, a ship, or a robot.

Figure 62 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile object control system to which the technology disclosed herein can be applied.

The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 62, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside vehicle information detection unit 12030, an inside vehicle information detection unit 12040, and an integrated control unit 12050. In addition, as functional configurations of the integrated control unit 12050, a microcomputer 12051, an audio/video output unit 12052, and an in-vehicle network I/F (interface) 12053 are shown.

The drive system control unit 12010 controls the operation of devices related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 functions as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

The body system control unit 12020 controls the operation of various devices installed in the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as headlamps, tail lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves or signals from various switches transmitted from a portable device that replaces a key can be input to the body system control unit 12020. The body system control unit 12020 accepts the input of these radio waves or signals and controls the vehicle's door lock device, power window device, lamps, etc.

The outside-vehicle information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, the image capturing unit 12031 is connected to the outside-vehicle information detection unit 12030. The outside-vehicle information detection unit 12030 causes the image capturing unit 12031 to capture images outside the vehicle and receives the captured images. The outside-vehicle information detection unit 12030 may perform object detection processing or distance detection processing for people, cars, obstacles, signs, or characters on the road surface based on the received images.

The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal according to the amount of light received. The imaging unit 12031 can output the electrical signal as an image, or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing off.

The microcomputer 12051 can calculate the control target values of the driving force generating device, steering mechanism, or braking device based on the information inside and outside the vehicle acquired by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an ADAS (Advanced Driver Assistance System), including vehicle collision avoidance or impact mitigation, following driving based on the distance between vehicles, maintaining vehicle speed, vehicle collision warning, or vehicle lane departure warning.

In addition, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving, which allows the vehicle to travel autonomously without relying on the driver's operation, by controlling the driving force generating device, steering mechanism, braking device, etc. based on information about the surroundings of the vehicle acquired by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040.

In addition, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information outside the vehicle acquired by the outside-vehicle information detection unit 12030. For example, the microcomputer 12051 can control the headlamps according to the position of a preceding vehicle or an oncoming vehicle detected by the outside-vehicle information detection unit 12030, and perform cooperative control for the purpose of preventing glare, such as switching from high beams to low beams.

The audio/image output unit 12052 transmits at least one output signal of audio and image to an output device capable of visually or audibly notifying the occupants of the vehicle or the outside of the vehicle of information. In the example of FIG. 62, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are exemplified as output devices. The display unit 12062 may include, for example, at least one of an on-board display and a head-up display.

Figure 63 is a diagram showing an example of the installation position of the imaging unit 12031.

In FIG. 63, vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as imaging unit 12031.

The imaging units 12101, 12102, 12103, 12104, and 12105 are provided, for example, at the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield inside the vehicle cabin of the vehicle 12100. The imaging unit 12101 provided at the front nose and the imaging unit 12105 provided at the upper part of the windshield inside the vehicle cabin mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 provided at the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 provided at the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The images of the front acquired by the imaging units 12101 and 12105 are mainly used to detect leading vehicles, pedestrians, obstacles, traffic lights, traffic signs, lanes, etc.

Figure 63 shows an example of the imaging ranges of imaging units 12101 to 12104. Imaging range 12111 indicates the imaging range of imaging unit 12101 provided on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of imaging units 12102 and 12103 provided on the side mirrors, respectively, and imaging range 12114 indicates the imaging range of imaging unit 12104 provided on the rear bumper or back door. For example, image data captured by imaging units 12101 to 12104 are superimposed to obtain an overhead image of vehicle 12100 viewed from above.

At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera consisting of multiple imaging elements, or may be an imaging element having pixels for phase difference detection.

For example, the microcomputer 12051 can extract, as a preceding vehicle, the three-dimensional object that is the closest to the vehicle 12100 on the path of travel and travels in approximately the same direction as the vehicle 12100 at a predetermined speed (for example, 0 km/h or more) by calculating the distance to each three-dimensional object within the imaging range 12111 to 12114 and the change in this distance over time (relative speed to the vehicle 12100) based on the distance information obtained from the imaging units 12101 to 12104. Furthermore, the microcomputer 12051 can set the vehicle distance to be secured in advance in front of the preceding vehicle and perform automatic brake control (including follow-up stop control) and automatic acceleration control (including follow-up start control). In this way, cooperative control can be performed for the purpose of autonomous driving, which runs autonomously without relying on the driver's operation.

For example, the microcomputer 12051 classifies and extracts three-dimensional object data on three-dimensional objects, such as two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects, based on the distance information obtained from the imaging units 12101 to 12104, and can use the data to automatically avoid obstacles. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. Then, the microcomputer 12051 determines the collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or exceeds a set value and there is a possibility of a collision, the microcomputer 12051 can provide driving assistance for collision avoidance by outputting an alarm to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or avoidance steering via the drive system control unit 12010.

At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether or not a pedestrian is present in the captured images of the imaging units 12101 to 12104. The recognition of such a pedestrian is performed, for example, by a procedure of extracting feature points in the captured images of the imaging units 12101 to 12104 as infrared cameras and a procedure of performing pattern matching processing on a series of feature points that indicate the contour of an object to determine whether or not the object is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the captured images of the imaging units 12101 to 12104 and recognizes the pedestrian, the audio/image output unit 12052 controls the display unit 12062 to superimpose a rectangular contour line for emphasis on the recognized pedestrian. The audio/image output unit 12052 may also control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

The above describes an example of a vehicle control system to which the technology disclosed herein can be applied. The technology disclosed herein can be applied to, for example, the imaging unit 12031 of the configuration described above. Specifically, for example, the imaging device 1 of Figures 1, 9, and 11 to 22 can be applied to the imaging unit 12031. By applying the technology disclosed herein to the imaging unit 12031, it is possible to achieve a smaller and lower-profile device configuration and suppress the occurrence of flare and ghosting caused by internal reflection.

The present disclosure can also be configured as follows.
<1> A solid-state imaging element that generates a pixel signal by photoelectric conversion in accordance with the amount of incident light;
a lens group including a plurality of lenses that focuses the incident light onto a light receiving surface of the solid-state imaging device;
a lowermost layer lens constituting a lowermost layer in the lens group with respect to an incident direction of the incident light is configured at a front end with respect to a direction in which the incident light is received,
The imaging device, wherein the bottom layer lens is an aspheric concave lens having an anti-reflection film formed on its surface.
<2> The lowest layer lens has an effective area for collecting the incident light onto the solid-state imaging element,
The imaging device according to <1>, wherein the anti-reflection film is formed at least in an effective area of the lowermost lens.
<3> The effective area is disposed at a substantially center with respect to a width of the lowermost layer lens in a direction perpendicular to the incident light, and a non-effective area is set on the outer periphery of the effective area so that the incident light is not necessarily focused on the solid-state imaging element,
The imaging device described in <2>, wherein when the anti-reflection film is provided on the non-effective area, the side of the lowest layer lens, and a glass substrate provided on the solid-state imaging element to which the lowest layer lens is attached, at least a portion of the glass substrate is provided with an area where the anti-reflection film is not formed.
<4> The imaging device described in <3>, wherein a width of the effective area, a width of the non-effective area, a width of the area where the glass substrate is exposed, and a width of the area where a scribe line is set satisfy a relationship of: width of the effective area>width of the non-effective area>width of the area where the glass substrate is exposed>width of the area where the scribe line is set.
<5> In the non-effective region, a bank-shaped protrusion having a thickness from the glass substrate greater than the maximum thickness of the bottom layer lens and a flat portion is formed,
The imaging device according to <3>, wherein the anti-reflection film is formed on a part of the protruding portion.
<6> The imaging device according to <5>, wherein the anti-reflection film is formed on a side surface of the protrusion on the effective area side and on the flat portion.
<7> The imaging device according to <6>, wherein the anti-reflection film is formed on a side surface of the protrusion on the effective area side, on the flat portion, and on an area up to a predetermined height from the flat portion of an outer peripheral side surface of the protrusion.
<8> The imaging device according to <7>, wherein the anti-reflection film is formed near a boundary between the lowermost lens and the glass substrate.
<9> The imaging device according to any one of <1> to <8>, wherein a side surface is formed in multiple steps on an outer periphery of the bottom layer lens.
<10> The imaging device according to any one of <1> to <9>, wherein the solid-state imaging element has a laminated structure and a cavity-less structure.

1 imaging device, 10 integrated component, 11 (CPS structure) solid-state imaging element, 11a lower substrate (logic substrate), 11b upper substrate (pixel sensor substrate), 11c color filter, 11d on-chip lens, 12 glass substrate, 13 adhesive, 14 IRCF (infrared cut filter), 14' IRCF glass substrate, 15 adhesive, 16 lens group, 17 circuit substrate, 18 actuator, 19 connector, 20 spacer, 21 pixel region, 22 control circuit, 23 logic circuit, 32 pixel, 51 photodiode, 81 silicon substrate, 83 wiring layer, 86 insulating film, 88 silicon through-hole electrode, 91 solder mask, 101 silicon substrate, 103 wiring layer, 105 chip through-hole electrode, 106 Connection wiring, 109 Silicon through-hole electrode, 131 Lens, 151 Adhesive, 171 Lens group, 191 (COB structure) solid-state imaging element, 192 Wire bond, 211 Infrared light cut resin, 231 Glass substrate, 231a Convex portion, 231b Cavity, 251 Coating agent having infrared light cut function, 271 Lens, 271a AR coating, 291 Lens, 291a Anti-reflection processing portion, 301 Infrared light cut lens, 321 Glass substrate, 351 Refractive film, 371, 371-1 to 371-4, 381 Additional film, 401, 401A to 401U, 401AA to AH Lens, 401a Protrusion, 401b, 401b' footing portion, 401d footing portion, 402, 402A to 402U, 402AA to AH, 402-P1 to 402-P5 AR coating, 451 substrate, 452, 452', 452'', 452''' molding die, 453 light-shielding film, 461 ultraviolet light curing resin, 461a seepage portion, 501, 501', 501A to 501K alignment marks, 521 light-shielding film, 531 bank

Claims (4)

a solid-state imaging element that generates pixel signals by photoelectric conversion in accordance with the amount of incident light;
a lens group including a plurality of lenses that focuses the incident light onto a light receiving surface of the solid-state imaging device;
a lowermost layer lens constituting a lowermost layer in the lens group with respect to an incident direction of the incident light is configured at a front end with respect to a direction in which the incident light is received,
the bottom layer lens is an aspheric concave lens, and has an effective area for condensing the incident light onto the solid-state imaging element, and an anti-reflection film is formed on at least the surface of the effective area of the bottom layer lens;
the effective area is disposed at approximately the center of the width of the lowermost layer lens in a direction perpendicular to the incident light, and a non-effective area is set on the outer periphery of the effective area so that the incident light is not necessarily focused on the solid-state imaging element;
An imaging device in which the anti-reflection film is further provided on a bank-shaped protrusion with a flat portion formed in the non-effective area and having a thickness from the glass substrate described below that is thicker than the thickest thickness of the effective area of the lowest layer lens, on the side of the lowest layer lens, and on a glass substrate provided on the solid-state imaging element to which the lowest layer lens is attached, and among these, on the side of the lowest layer lens, an area on which the anti-reflection film is not formed is provided in an area from a position closer to the glass substrate by a predetermined width as viewed from the flat portion of the protrusion to a position closer to the flat portion by a predetermined width as viewed from a position near the boundary between the lowest layer lens and the glass substrate. a region in which a scribe line is set on the outermost periphery of the solid-state imaging element;
2. The imaging device according to claim 1, wherein the width of the effective area, the width of the non-effective area, the width of the area where the glass substrate is exposed, and the width of the area where the scribe line is set satisfy the relationship: width of the effective area > width of the non-effective area > width of the area where the glass substrate is exposed > width of the area where the scribe line is set. The imaging device according to claim 1 , wherein a side surface of the lowermost lens is formed in multiple steps on an outer periphery of the lowermost lens. The imaging device according to claim 1 , wherein the solid-state imaging element has a laminated structure and a cavity-less structure.

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