JP5203318B2 - Imaging module and manufacturing method thereof - Google Patents

Description

  The present invention relates to an imaging module and a manufacturing method thereof.

  In Patent Document 1, the heat absorbing side and the heat radiating side are thermally separated, and accommodation of the working fluid that absorbs the heat from the back side insulating sheet of the image sensor through the opening of the FPC board and transfers the heat by phase change to dissipate the heat. The heat generated by the image pickup device is transferred from the back side insulating sheet to the heat pipe by convection and radiation, absorbs heat by the phase change of the working fluid, and dissipates heat. It is described that the heat of the element is transferred to the element support member by heat conduction and exhausted.

  In Patent Document 2, the image pickup device includes a package in which an image pickup unit is accommodated, and a holder is attached in a state of projecting from the frame portion surrounding the package and the image pickup unit facing the optical path of the optical system. A mounting plate portion to be attached to the seat, and an adhesive filling notch portion provided in the frame portion. The adhesive filling notch portion is formed in an open shape at the lower end of the lower wall, and It is described that three are provided at intervals in the extending direction of the side surface.

JP 2008-271487 A JP-A-2005-121912

  In recent years, in imaging devices (cameras) such as digital still cameras and digital video cameras, the number of pixels and the density of imaging devices (imaging units) used are increasing, and the temperature of the imaging unit associated with long-time imaging. There is a problem that image noise and image degradation occur due to the rise. For this reason, it is required to efficiently dissipate heat generated from a CCD image sensor, a CMOS image sensor, or an imaging unit including them. In addition, when mounting an imaging unit or an imaging module including an imaging unit in an imaging apparatus, it is also important that the lens can be optically positioned with high accuracy.

  In the technique disclosed in Patent Document 1, it is described that the heat generated in the imaging element is transferred to a heat pipe and transferred to the element support member by heat conduction to be exhausted. However, since the heat pipe is used to transfer heat from the image pickup element to the element support member that is a heat radiating member, the configuration is complicated and the assembly work is not so easy.

  In the technique disclosed in Patent Document 2, for the optical positioning of the image sensor, it is described that a mounting plate portion that is attached to the mounting seat in a state where the imaging unit faces the optical path of the optical system is described. Has been. However, no means for dissipating the heat generated from the image sensor is provided, and image noise and image degradation may occur due to the temperature rise of the image sensor.

  It is possible to promote heat dissipation from the CCD image sensor using a heat radiating plate (heat radiating member). However, it is not so easy to attach the CCD image sensor to the heat radiating plate so that the heat radiation efficiency is good and the CCD image sensor is optically positioned accurately. For example, when an imaging element (imaging unit) such as a CCD image sensor is made of ceramic having high thermal conductivity, a heat dissipation effect is enhanced and a reduction in thickness can be expected. However, the tolerance (individual difference) of a ceramic package manufactured by a method such as sintering is relatively large compared to a resin-based package manufactured by a method with relatively high accuracy such as a mold. It is not so easy to accurately position the imaging surface (light receiving surface) optically. Therefore, if priority is given to heat dissipation efficiency, it is desirable that the CCD image sensor is in close contact with the heat sink, but it is necessary to adjust the tilt of the CCD image sensor in order to install the CCD image sensor at an optically accurate position. The CCD image sensor cannot be brought into close contact with the heat sink.

One embodiment of the present invention is a method for manufacturing an imaging module mounted on a camera. The imaging module is an imaging unit (image sensor, imaging device, imaging element) including a plurality of light receiving elements, and includes an imaging unit having a front surface including an imaging surface and a back surface facing the imaging surface, a heat sink, a holder, The holder includes a first surface serving as an optical reference when the imaging module is mounted on the camera, and the method includes the following steps.
A first step of attaching the imaging unit to the heat sink so that the back surface of the imaging unit is thermally connected to the heat sink.
-Align the imaging surface of the imaging unit attached to the heat sink and the first surface of the holder (alignment adjustment), and fix the heat sink and holder by filling the resin in the connection holes of the heat sink The second step to do.

  In this manufacturing method, the first surface and the imaging surface of the imaging unit are aligned in the second step of fixing the holder including the first surface serving as a reference when mounting and the heat sink with resin. Do. When positioning is performed in the second step, the inclination, distance, and the like between the first surface and the imaging surface are also adjusted to predetermined conditions. Therefore, when attaching the imaging unit to the heat sink, priority can be given to the thermal contact between the imaging unit and the heat sink with respect to the position of the imaging unit, that is, the position and the inclination. Therefore, in this manufacturing method, connecting the imaging unit to the heat radiating plate with good heat transfer efficiency, and fixing the imaging unit so as to be in a predetermined position and orientation in the imaging module, Can be done independently. Accordingly, it is possible to manufacture an imaging module that has high heat dissipation efficiency from the imaging unit, is compact, and can accurately set the imaging unit with respect to a lens or the like.

  In the second step, it is desirable to fill resin into at least three connection holes arranged so that the inclination of the heat sink is determined around the imaging unit to which the heat sink is attached. Since the heat sink and the holder can be adjusted including inclination, the relationship between the imaging surface of the imaging unit attached to the heat sink and the first surface of the holder can be set with higher accuracy. Accordingly, it is possible to provide an imaging module that is easy to dissipate heat from the imaging unit, has high positional accuracy of the imaging unit (imaging surface) in the imaging module, and can be easily mounted on a camera or the like. Furthermore, since the second process can be designed centering on alignment adjustment rather than heat transfer, a UV curable resin suitable for alignment adjustment can be used as the resin used in the second process, although the thermal conductivity is not high.

  One of the different aspects of the present invention is a plate-like imaging unit (image sensor, imaging device, imaging element) having a plurality of light receiving elements, a heat sink to which the imaging unit is attached, and a heat sink. An imaging module having a holder. The imaging unit includes a front surface that includes an imaging surface and a back surface that faces the front surface. The holder includes a first surface serving as a reference when the imaging module is mounted on the camera. The heat radiating plate includes a plurality of connection holes for aligning the image pickup surface of the image pickup unit and the first surface of the holder when the heat radiating plate is attached to the holder around the attached image pickup unit. Are thermally connected, and the holder and the heat sink are fixed by a resin filled in a plurality of connection holes.

  In this imaging module, when fixing the heat sink to the holder, the image pickup surface of the image pickup unit attached to the heat sink and the first surface of the holder can be aligned so as to satisfy a predetermined condition. For this reason, the imaging module can be attached to the camera based on the first surface of the holder. Furthermore, since the imaging unit can be attached with priority to thermal contact with the heat sink, it is easy to obtain a higher heat dissipation effect. Accordingly, it is possible to provide an imaging module that has a simple configuration, has a high heat dissipation effect, has high positional accuracy of the imaging unit (imaging surface) in the imaging module, and can be easily mounted on a camera.

  In this imaging module, it is desirable that a heat conductive film is sandwiched between the imaging unit and the heat sink. By sandwiching a heat conductive film that has high thermal conductivity and is easily deformed between the imaging unit and the heat sink, it is possible to suppress the formation of a gap between the image pickup unit and the heat sink. Heat can be transferred more efficiently.

  It is desirable that the heat radiating plate includes a convex portion protruding toward the back surface of the imaging unit. The convex portion of the heat sink is easily brought into contact with the central portion of the back surface of the image pickup unit that is likely to be hot, and heat is easily transferred from the image pickup unit to the heat sink.

  The imaging module may include a flexible substrate on which the back surface of the imaging unit is a mounting surface and the imaging unit is mounted. The flexible substrate can be disposed between the imaging unit formed by the convex portion of the heat sink and the heat sink (gap).

  It is desirable that the plurality of connection holes of the heat sink include at least three connection holes arranged so as to determine the inclination of the heat sink around the attached imaging unit. Since the heat sink can be adjusted and fixed with respect to the holder with an inclination, the imaging surface of the imaging unit attached to the heat sink and the first surface of the holder can be aligned with higher accuracy.

  One of the different aspects of the present invention is a camera having the imaging module and a lens aligned with the first surface of the holder of the imaging module. By aligning the lens with the first surface of the imaging module (holder), the relationship between the imaging surface and the lens in the imaging module can be set to a predetermined relationship (optical position). Therefore, the labor for mounting the imaging module on the camera can be reduced, and the camera can be provided at a lower cost.

The figure which showed typically the outline | summary of the camera which mounts an imaging module. The perspective view which looked at the imaging module from the front side (the imaging surface side). The perspective view which looked at the imaging module from the back side (the side opposite to an imaging surface). The figure which expanded the imaging module to the main parts which comprise an imaging module. The figure which expanded the imaging module to the holder and the subassembly. The front view of an imaging module. VII-VII sectional drawing of an imaging module. VIII-VIII sectional drawing of an imaging module.

  FIG. 1 schematically shows an outline of a camera 100 equipped with an imaging module 1 according to the present invention. The camera 100 includes a body 97, the imaging module 1 housed in the body 97, and a lens module 98 attached to the front of the imaging module 1. The lens module 98 includes one or a plurality of lenses 99 and is assembled so that the reference surface 93 of the lens module 98 and the first surface (reference surface) 31 of the imaging module 1 are in contact with each other. The reference surface 93 of the lens module 98 and the reference surface 31 of the imaging module 1 are assembled by assembling the lens module 98 and the imaging module 1 based on the reference surfaces 31 and 93, thereby including an imaging unit ( The optical positional relationship between the image sensor, the imaging device, and the imaging device 20 (more specifically, the imaging surface 23 of the imaging unit 20) and one or a plurality of lenses 99 included in the lens module 98 is expressed by the imaging unit 20. The optical system including the lens (lens system) 99 is designed. Therefore, when the camera 100 is assembled, the reference surfaces 31 and 93 may be in direct contact with each other, and the reference surfaces 31 and 93 are assembled in a predetermined relationship via an appropriate member (alignment device). It may be done.

  The imaging module 1 includes an imaging unit 20, a flexible substrate 60 on which the imaging unit 20 is mounted, and a holder 30 that covers the surface (front surface) 21 side of the imaging unit 20 including the imaging surface (light receiving surface) 23 of the imaging unit 20. And the heat sink 10 attached to the back surface (rear surface) 22 of the imaging unit 20. The camera 100 further includes a control unit 2 to which an elastically deformable flexible substrate 60 is connected. Image data acquired by the imaging unit 20 is processed by the control unit 2 and displayed as an image on the LCD 3. Further, the image data acquired by the imaging unit 20 is recorded in the flash memory 5 by operating the operation button 4 such as a shutter.

  FIG. 2 shows a state where the imaging module 1 is extracted and viewed from the front side (imaging surface 23 side) 1a. FIG. 3 shows a state in which the imaging module 1 is viewed from the back side (the side opposite to the imaging surface 23) 1b. FIG. 4 shows a state in which the imaging module 1 is developed on main parts constituting the imaging module 1. FIG. 5 shows a state in which the imaging module 1 is deployed on the holder 30 and the subassembly 40.

  As shown in these drawings, the imaging module 1 has a structure in which a subassembly 40 including the imaging unit 20 and a holder 30 are stacked from the back side 1b. The holder 30 is provided with a flat surface (reference surface) 31 as viewed from the front side 1a, and serves as a reference surface (reference surface) when combined with the lens module 98 as described above.

  A part of the cover assembly 49 that covers the imaging unit 20 in the sub-assembly 40 appears on the front side 1 a from the opening 34 of the holder 30. A central portion of the cover assembly 49 is a window 48 through which light passes. For this reason, the light condensed by the lens module 98 reaches the imaging surface 23 in which the light receiving elements of the imaging unit 20 are arranged in the two-dimensional direction through the window 48. The imaging unit 20 is made of ceramic having high thermal conductivity, and is an imaging device (image sensor or imaging device) in which a plurality of light receiving elements are arranged on the imaging surface 23, and is typically a CCD image sensor or a CMOS image sensor. Etc. The imaging unit 20 converts information of an image formed on the imaging surface 23 into an electrical signal (image data) and outputs the electrical signal through the flexible substrate 60.

  The subassembly 40 includes a heat sink 10, an image pickup unit 20 attached to the surface 10 a side of the heat sink 10, and a cover assembly 49 that covers the surface 21 side of the image pickup unit 20. The imaging unit 20 has a back surface 22 mounted on the flexible substrate 60 as a mounting surface. Therefore, the imaging module 1 includes a plate-shaped imaging unit 20 including an imaging surface 23 in which a plurality of light receiving elements are arranged, a heat sink 10 to which the image pickup unit 20 is attached, and a holder 30 attached to the heat sink 10. Have When the subassembly 40 is manufactured, the imaging unit 20 has the back surface 22 facing the front surface 21 including the imaging surface 23 thermally connected to the heat sink 10.

  The heat radiating plate 10 includes three connection holes 11 for attaching the heat radiating plate 10 to the holder 30 with an inclination around the attached imaging unit 20. The connection hole 11 penetrates the heat sink 10. As shown in FIG. 3, when the subassembly 40 is attached to the holder 30, the connection hole 11 of the heat sink 10 and the connection portion 35 provided on the back surface 32 of the holder 30 are combined, and the UV curable resin 71 is attached to the connection hole. 11 and the subassembly 40 and the holder 30 are fixed by irradiating ultraviolet rays. Before the UV curable resin 71 is cured, the imaging surface 23 of the imaging unit 20 and the reference surface 31 of the holder 30 are aligned, and the planar position, angle, and reference surface of the imaging surface 23 and the reference surface 31 are further determined. The distance (depth) between 31 and the imaging surface 23 is set to a predetermined relationship according to the design. Therefore, the imaging module 1 adjusted so that the imaging surface 23 and the reference surface 31 are in a predetermined positional relationship can be provided.

  The method for manufacturing the imaging module 1 will be described in more detail with reference to FIGS. 6 shows a state in which the imaging module 1 is viewed from the front, FIG. 7 shows a longitudinal sectional view of the imaging module 1 (VII-VII cross section in FIG. 6), and FIG. FIG. 8 is a cross-sectional view in the horizontal direction (cross section VIII-VIII in FIG. 6).

  First, as shown in FIG. 4, the imaging unit 20 and the heat sink 10 are attached so as to be thermally connected (first step). Further, the imaging unit 20 is covered with the cover assembly 49, and the subassembly 40 is assembled (manufactured). After that, as shown in FIG. 5, the heat sink 10 and the holder 30 are assembled so that the imaging surface 23 of the imaging unit 20 and the reference surface 31 of the holder 30 are in a predetermined positional relationship, and are fixed by the UV curable resin 71. (Second step).

  In the vicinity of the center of the heat radiating plate 10, a convex portion 15 protruding toward the imaging unit 20 is provided. The imaging unit 20 is attached to the heat sink 10 with a heat conductive film 19 sandwiched between the back surface 22 and the convex portion 15 of the heat sink 10. In this example, the imaging unit 20 is provided in a state where the imaging unit 20 is mounted on a flexible substrate 60 in which a portion facing the convex portion 15 is an opening 61. The imaging unit 20 is attached to the heat radiating plate 10 with screws 18 from the surface 21 side of the imaging unit 20 together with the flexible substrate 60 by a cover assembly 49. Therefore, the imaging unit 20 is attached to the heat sink 10 while being sandwiched between the cover assembly 49 and the heat sink 10.

  The heat sink 10 is provided with three holes 17 for fixing the cover assembly 49 through the three screws 18. The angle of the cover assembly 49 can be adjusted by attaching the cover assembly 49 to the heat radiating plate 10 at three locations, and the imaging unit 20 can dissipate heat while sandwiching the heat conduction film 19 without applying a biased load to the imaging unit 20. It can be attached to the plate 10. Therefore, the imaging unit 20 and the heat sink 10 can be fixed with good heat transfer. For this reason, the heat which generate | occur | produced in the imaging unit 20 can be efficiently transmitted to the heat sink 10, and it can suppress that the imaging unit 20 overheats. The number of screws 18 and holes 17 is not limited to three and may be four or more.

  The cover assembly 49 includes, from the surface 21 side of the imaging unit 20, a sensor cover 42 for fixing the imaging unit 20 to the heat sink 10, and a low-pass filter 43 attached to the substantially rectangular opening 42 a of the sensor cover 42. The filter rubber 44 and the filter holder 45 for fixing the filter 43 and the rubber 44 are included. The opening 42 a of the sensor cover 42 is open in the optical axis direction 101 of the imaging surface 23 of the imaging unit 20. The sensor cover 42 includes a fixing hole 47 of the screw 18 for attaching to the heat sink 10. The low-pass filter 43 is for eliminating moiré (interference fringes) and the like, and the filter rubber 44 shields the periphery of the imaging surface 23 of the imaging unit 20 and also the imaging surface 23 of the imaging unit 20 and the low-pass filter 43. This is to prevent dust from entering the surface 43a. The filter holder 45 includes four locking portions 45 a and is attached to four locking protrusions 42 b formed on the sensor cover 42.

  The heat conductive film 19 attached to the back surface 22 of the imaging unit 20 can be formed of an elastic sheet such as a silicon-based elastomer having a high thermal conductivity, or a resin agent (adhesive) such as an epoxy having a high thermal conductivity. The heat conductive film 19 has high heat conductivity and also has elasticity. For this reason, the tolerance at the time of attaching the image pick-up unit 20 and the heat sink 10 can be absorbed, and the curvature and distortion between the image pick-up unit 20 and the heat sink 10 by the difference in a thermal expansion coefficient can be absorbed. Therefore, it is possible to suppress the occurrence of a gap between the back surface 22 of the imaging unit 20 and the convex portion 15 of the heat sink 10. For this reason, the back surface 22 of the imaging unit 20 and the convex part 15 of the heat sink 10 can be kept in close contact from the point of heat transfer, and a sufficient area required for heat transfer can be secured. Therefore, the heat generated in the ceramic package type imaging unit 20 with good heat dissipation efficiency can be efficiently released to the outside through the heat sink 10. At the same time, even if there is some tolerance in the outer shape of the ceramic package of the imaging unit 20, the package and the heat sink 10 can be brought into thermal contact with each other via the heat conductive film 19.

  Further, since the heat conductive film 19 is elastic, vibrations and shocks applied to the imaging unit 20 during the manufacturing process of the imaging module 1 and the camera 100 and when the camera 100 is used can be reduced. For this reason, generation | occurrence | production of the electrical trouble of the imaging unit 20 can be suppressed, and also since the attachment position of the imaging unit 20 can also be suppressed, generation | occurrence | production of an optical trouble can also be suppressed.

  In the imaging module 1, the optical alignment of the imaging surface 23 of the imaging unit 20 can be performed in the process of attaching the subassembly 40 including the imaging unit 20 to the holder 30 (second process). For this reason, in the process of attaching the back surface 22 of the image pickup unit 20 and the heat sink 10 (first process), the alignment (optical alignment adjustment) of the image pickup unit 20 is basically unnecessary. A resin having a high thermal conductivity such as an epoxy resin can be selected to attach the imaging unit 20 to the heat radiating plate 10 instead of a resin that is suitable for such alignment adjustment but has a low thermal conductivity.

  In addition, it is also possible to attach the imaging unit 20 to the heat sink 10 directly, that is, excluding the heat conduction film 19, and it is possible to suppress the imaging unit 20 from being overheated by radiating heat through the heat sink 10. Although the heat sink 10 may be a flat plate not provided with the convex portion 15, it is easy to secure a thermal contact area between the back surface 22 of the imaging unit 20 and the heat sink 10 by providing the convex portion 15. . In this example, the convex portion 15 is provided on the heat radiating plate 10, and the heat conductive film 19 is sandwiched between the convex portion 15 and the imaging unit 20, so that the heat generated from the imaging unit 20 is efficiently transmitted to the radiating plate 10. Can communicate well. Moreover, since the vicinity of the center of the back surface 22, which is likely to be high in the image pickup unit 20, can be thermally connected to the heat sink 10, the heat of the image pickup unit 20 can be more efficiently transferred to the heat sink 10.

  Furthermore, as shown in FIG. 7 and FIG. 8, by providing the heat sink 10 with a convex portion 15 protruding in the direction of the imaging unit 20 and making the area of the convex portion 15 slightly smaller than the back surface 22 of the imaging unit 20, A gap 29 can be provided between the heat sink 10 around the convex portion 15 and the imaging unit 20. By adjusting the protrusion amount of the convex portion 15, the flexible substrate 60 can be disposed in the gap 29, and interference between the heat sink 10 and the flexible substrate 60 can be prevented. For this reason, the imaging unit 20 can be thermally connected to the heat sink 10 without being obstructed by the flexible substrate 60. Further, since the flat flexible substrate 60 can be assembled along the flat heat sink 10, the subassembly 40 including the flexible substrate 60 and the imaging module 1 can be compactly assembled.

  Further, as shown in FIG. 7, the flexible substrate (flexible printed circuit board) 60 is fixed to the heat sink 10 by UV curable resin 71 injected into two holes 12 provided in the heat sink 10. Therefore, the imaging unit 20 mounted on the flexible substrate 60 is also fixed to the heat sink 10 through the flexible substrate 60 in addition to the heat conductive film 19 and the cover assembly 49. When the imaging module 1 is incorporated in an optical device such as the camera 100, the flexible substrate 60 is connected to the control unit 2 of the optical device, and at that time, an external force may be applied to the flexible substrate 60. By fixing the flexible substrate 60 to the heat radiating plate 10, it is possible to suppress external force applied to the imaging unit 20 during assembly of the optical device. For this reason, it is possible to prevent the alignment of the imaging unit 20 from being out of order due to an external force when the optical apparatus is assembled.

  The heat sink 10 to which the imaging unit 20 is attached is an aluminum plate having high thermal conductivity. The heat radiating plate 10 may be made of copper or other metal plate having high thermal conductivity. The heat sink 10 has three connection holes 11 around the imaging unit 20 to which it is attached. These three connection holes 11 are distributed so as to be able to define the inclination of the heat radiating plate 10 when being attached to the holder 30, and are arranged so as to have a substantially triangular apex. In the heat sink 10 of this example, as shown in FIGS. 4 and 5, the three connection holes 11 are around a region 16 where the substantially rectangular imaging unit 20 is to be attached, It is provided in each of the regions outside the three sides of the four sides. There may be four or more connection holes 11.

  As shown in FIG. 5, after the imaging unit 20 is attached to the heat radiating plate 10 by the cover assembly 49 to form the subassembly 40, the subassembly 40 is attached to the holder 30 via the heat radiating plate 10 of the subassembly 40 (first). Step 2).

  The holder 30 includes a reference surface (first surface) 31 that serves as a reference when the imaging module 1 is mounted on the camera 100. In this example, a part of the surface of the holder 30 viewed from the front side 1 a is a reference surface 31. The radiator plate 10 of the subassembly 40 is provided with three connection holes 11 for attaching the radiator plate 10 to the holder 30 including the inclination of the radiator plate 10 around the attached imaging unit 20. Therefore, when the UV curable resin 71 is injected into the connection hole 11 and the heat sink 10 is fixed to the holder 30, the positional relationship between the heat sink 10 and the holder 30 is equivalent to the center 23 a of the imaging surface 23 in the optical axis direction 101. In order to adjust to the correct axis, not only shift adjustment in the plane perpendicular to the optical axis direction 101 (center alignment in the XY direction) and height adjustment of the imaging surface 23 (Z adjustment), but also the heat sink 10 and the holder 30 (tilt adjustment (angle adjustment) of the imaging surface 23) and rotation angle adjustment (roll adjustment) around the optical axis direction 101 can be adjusted.

  Further, as shown in FIGS. 3, 7, and 8, a connection portion 35 is provided at a position facing the connection hole 11 of the heat radiating plate 10 on the back surface 32 of the holder 30, and the connection portion 35 is a sub-assembly 40. And a protrusion 36 protruding toward the surface. By providing the convex protrusions 36, it is possible to secure a bonding area between the adhesive (UV curable resin) 71 injected into the connection holes 11 of the heat sink 10 and the holder 30. Therefore, the subassembly 40 can be firmly fixed to the holder 30 so as to be adjusted to a predetermined positional relationship and to maintain the positional relationship.

  Position adjustment (positioning) between the subassembly 40 and the holder 30 is performed between the imaging surface 23 of the imaging unit 20 attached to the heat radiating plate 10 and a reference surface (first surface) 31 of the holder 30. That is, the holder 30 and the subassembly 40 are attached to an alignment device (not shown), and shift adjustment (center adjustment (XY) of the imaging surface 23 between the imaging surface 23 of the imaging unit 20 and the reference surface 31 of the holder 30 is performed. Adjustment)), height adjustment (Z adjustment), tilt adjustment (θ adjustment), and roll adjustment (φ adjustment) if necessary. Thereafter, a UV curable resin 71 is injected into the connection hole 11 and cured by irradiation with ultraviolet rays. The alignment adjustment may be performed before UV irradiation, and the resin injection into the connection hole 11 may be performed before or after the alignment adjustment.

  One of the alignment methods is to perform image processing by capturing the imaging surface 23 of the imaging unit 20 and the reference surface 31 of the holder 30 with a camera. In addition, the holder 30 is temporarily attached to the lens unit for inspection, the image output of the imaging unit 20 is monitored, and alignment is performed by obtaining an image with a predetermined resolution from the imaging unit 20 at a predetermined position. Is possible. It is also possible to adopt a method such as measuring the positional relationship between the reference surface 31 of the holder 30 and the imaging surface 23 of the imaging unit 20 using an appropriate measuring device and adjusting the positional relationship to a predetermined positional relationship. .

  Regardless of which method is employed, in the imaging module 1 of the present example, by adjusting the mounting position of the heat sink 10 and the holder 30, the reference plane 31 of the holder 30 and the imaging plane 23 of the imaging unit 20 are adjusted. Alignment is possible. Therefore, when the image pickup unit 20 is attached to the heat sink 10, optical alignment is basically unnecessary, and the heat sink 10 and the image pickup unit 20 are in heat transfer close contact with the image pickup surface 23. The imaging module 1 adjusted so as to have a predetermined positional relationship with the reference plane 31 can be provided.

  In this example, each of the stoppers 47a has a size that allows the stoppers 47a to enter three places around the opening 34 of the holder 30 that are engaged with the three stoppers 47a extending from the sensor cover 42 in three directions. A recess (notch) 37 is provided. With these stoppers 47a and recesses 37, as shown in FIG. 6, when assembling the subassembly 40 and the holder 30, a clearance 49a is always opened between the holder 30 and the cover assembly 49 except for the periphery of the stopper 47a. It is like that. A fixing hole 47 for attaching the cover assembly 49 to the heat sink 10 is provided on the back surface of the stopper 47a. Therefore, when attaching the subassembly 40 to the holder 30, the rough positional relationship between the subassembly 40 and the holder 30 can be adjusted by the stopper 47 a having the highest attachment strength with respect to the heat sink 10. For this reason, the imaging unit 20 is secured to the heat sink 10 with the screw 18 by the cover assembly 49 and is strong against an impact at the time of assembly. Further, when the subassembly 40 and the holder 30 are assembled. Even if the subassembly 40 and the holder 30 come into contact with each other, the impact applied to the imaging unit 20 can be suppressed.

  As described above, in the imaging module 1 manufactured by the manufacturing method having the first step shown in FIG. 4 and the second step shown in FIG. 5, the imaging surface 23 of the imaging unit 20 and the reference surface of the holder 30. 31 is adjusted (alignment adjustment) so as to have a predetermined positional relationship. For this reason, when the camera 100 shown in FIG. 1 is assembled, the lens module 98 and the imaging are obtained by aligning the reference surface 31 of the holder 30 with the reference surface 93 of the lens module 98, for example, the connecting portion of the lens barrel. Optical alignment (alignment adjustment) with the surface 23 can be easily performed. Then, the lens module 98 condenses the light on the imaging surface 23 of the imaging unit 20 through the window 48 of the cover assembly 49 that appears from the opening 34 opened in the optical axis direction 101 near the center of the holder 30, and forms an image. Can be made.

  Further, in the imaging module 1, the alignment of the imaging surface 23 of the imaging unit 20 and the reference surface 31 of the holder 30 can be performed in the process of attaching the subassembly 40 to the holder 30 (second process). Therefore, in the process of attaching the back surface 22 of the image pickup unit 20 and the heat sink 10 (first step), the image pickup unit 20 and the heat sink 10 can be fixed in a state in which heat transfer from the image pickup unit 20 to the heat sink 10 is easy. . For this reason, the heat generated from the imaging unit 20 can be efficiently transmitted to the heat radiating plate 10, and the heat can be efficiently released from the imaging unit 20 to the outside.

  In particular, in the imaging unit 20 using a ceramic package that prioritizes heat dissipation efficiency in recent years, by adopting this manufacturing method, even if the ceramic package includes some manufacturing tolerances, the heat dissipation of the ceramic package. The imaging module 1 with high optical accuracy can be provided while taking advantage of the above. Further, since the alignment adjustment of the imaging module 1 is performed between the holder 30 and the subassembly 40, specifically, between the holder 30 and the heat radiating plate (heat radiating member) 10, no external force is applied to the imaging unit 20. Therefore, damage to the imaging unit 20 at this stage can be suppressed.

  As described above, according to the present invention, the heat radiation plate (heat radiation member) is used, the heat radiation efficiency is good with a simpler and more compact configuration than the heat pipe, and the optical reference surface 31 and the imaging surface (light receiving surface) of the imaging unit 20. ) The imaging module 1 that can be easily aligned (alignment adjustment) with 23 can be provided. For this reason, it is possible to provide the imaging module 1 in which the reference plane 31 and the imaging plane 23 of the imaging module 1 are accurately aligned, and the reference plane 31 of the imaging module 1 is incorporated into an optical device such as the camera 100. By aligning (alignment adjustment), it can be easily incorporated into an optical instrument. Further, when the imaging module 1 is incorporated into an optical device, the holder 30 of the imaging module 1 is used for alignment, and external force is not easily applied to the imaging unit 20 during the incorporation. Therefore, it is possible to prevent damage to the imaging unit 20 when assembling the optical apparatus.

  Therefore, by adopting the imaging module 1 of the present invention, it is possible to manufacture and provide an optical apparatus, for example, a camera, which can acquire a stable and clear image for a long time. Therefore, the imaging module 1 according to the present invention is mounted on various imaging devices such as a digital still camera and a digital video camera, and can be applied to various applications such as a WEB camera and a surveillance camera.

  In addition, among the order which assembles the parts demonstrated above, the assembly order of parts except the order which assembles the heat sink 10, the imaging unit 20, and the holder 30 is not limited above. For example, the low-pass filter 43, the filter rubber 44, and the filter holder 45, which are parts constituting the cover assembly 49 in the subassembly 40, are attached after the heat sink 10 and the holder 30 are assembled in a predetermined positional relationship. be able to. That is, when the heat sink 10 and the holder 30 in a state where the sensor cover 42 is assembled are assembled, the sensor cover 42 appears on the front side 1 a from the opening 34. Therefore, the low-pass filter 43, the filter rubber 44, and the filter holder 45 can be sequentially attached to the sensor cover 42.

DESCRIPTION OF SYMBOLS 1 Imaging module, 10 Heat sink, 11 Connection hole 20 Imaging unit, 21 Front surface, 22 Back surface, 23 Imaging surface 30 Holder, 31 1st surface (reference surface), 35 Connection part, 36 Protrusion 40 Subassembly, 42 Sensor cover 49 Cover assembly 60 Flexible substrate 71 UV curable resin 97 Body 98 Lens module 99 Lens 100 Camera

Claims (8)

A method of manufacturing an imaging module mounted on a camera,
The imaging module is an imaging unit including a plurality of light receiving elements, and includes an imaging unit having a front surface including an imaging surface and a back surface facing the imaging unit, a heat sink, and a holder. Including a first surface as a reference when the module is mounted on the camera;
The method is
A first step of attaching the imaging unit to the heat sink so that the back surface of the imaging unit is thermally connected to the heat sink;
The heat sink and the holder are formed by aligning the imaging surface of the imaging unit attached to the heat sink and the first surface of the holder and filling a plurality of connection holes of the heat sink with resin. And a second step of fixing. In claim 1,
The method includes filling the resin into at least three connection holes arranged to determine the inclination of the heat sink around the attached imaging unit of the heat sink. A plate-like imaging unit having a plurality of light receiving elements;
A heat sink to which the imaging unit is attached;
An imaging module having a holder attached to the heat sink,
The imaging unit includes a front surface including an imaging surface, and a back surface facing the surface,
The holder includes a first surface serving as a reference when the imaging module is mounted on a camera,
The heat radiating plate has a plurality of connection holes that align the imaging surface of the imaging unit and the first surface of the holder when the heat radiating plate is attached to the holder around the attached imaging unit. The imaging module and the heat sink are thermally connected, and the holder and the heat sink are fixed by a resin filled in the plurality of connection holes.   The imaging module according to claim 3, wherein a heat conductive film is sandwiched between the imaging unit and the heat dissipation plate.   5. The imaging module according to claim 3, wherein the heat radiating plate includes a protrusion protruding toward the back surface of the imaging unit. In Claim 5, the back side of the imaging unit is a mounting surface, and has a flexible substrate on which the imaging unit is mounted,
The flexible substrate is an imaging module disposed between the imaging unit and the heat dissipation plate. In any of claims 3 to 6,
The imaging module, wherein the plurality of connection holes of the heat sink include at least three connection holes arranged around the attached imaging unit so as to determine an inclination of the heat sink. The imaging module according to any one of claims 3 to 7,
A camera having a lens aligned with the first surface of the holder of the imaging module.

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