JP7742554B2 - Illuminated imaging device and position adjustment device - Google Patents

Description

The present invention relates to an illuminated imaging device that illuminates an object and captures an image, and a position adjustment device that uses the same to adjust the position of the object.

In recent years, various FA (Factory Automation) devices, such as processing machines and mounting machines in the electronics, electrical, and mechanical fields, have begun to use so-called visual feedback devices that obtain the position of an object based on captured images and move the object so that processing and mounting can be carried out appropriately.

When an object vibrates in response to the environment, a visual feedback device cannot capture a clear image, making it impossible to move the object properly. To address this issue, the technique described in Patent Document 1 below can be used, for example. Patent Document 1 below describes a method for capturing clear images by capturing images only when the amplitude of the vibration is below a predetermined threshold, even if the object being measured vibrates.

JP 2017-15483 A

The technique described in Patent Document 1 can capture clear images when the vibration amplitude is below a predetermined threshold, but stops capturing images when the vibration amplitude exceeds the predetermined threshold. Therefore, when the technique is applied to a visual feedback device, the object cannot be moved properly if the vibration amplitude exceeds the predetermined threshold.

In view of these problems, the present invention aims to provide an illuminated photographing device and a position adjustment device using the same that can properly capture an image of an object even when the object is vibrating.

An illuminated image capture device according to a first aspect of the present invention includes a projection unit that irradiates an object with illumination light, a detection unit that detects vibration of the object, a camera unit having a focus, and an analysis unit that estimates a period during which the focus is approximately aligned with the object based on a detection signal from the detection unit. The illuminated image capture device projects the illumination light from the projection unit onto an area that includes the object during the period estimated by the analysis unit, and stops projecting the illumination light outside of the period.

According to a second aspect of the present invention, there is provided an illuminated image capturing device including a projection unit that irradiates an object with illumination light, a detection unit that detects vibration of the object, a camera unit having a focal point, and an analysis unit that estimates a period during which the focal point substantially aligns with the object based on a detection signal from the detection unit. The illuminated image capturing device controls the camera unit to expose each pixel during the period estimated by the analysis unit, and controls the camera unit not to expose each pixel outside the period.

With the illuminated imaging devices of the first and second aspects, an image is captured using illumination light during a period when the camera's focus is approximately aligned with the object, resulting in a clear image with the camera's focus approximately aligned with the object. Therefore, even if the object is vibrating, an image of the object can be captured accurately.

A position adjustment device according to a third aspect of the present invention comprises an installation unit on which an object is installed, a drive unit that drives the installation unit to change the position of the object, an illuminated imaging device according to the first or second aspect, and a control unit that drives the drive unit using an image obtained by the illuminated imaging device as a feedback control image to adjust the position of the object to a target position.

The position adjustment device of this aspect uses the illuminated imaging device of the first or second aspect, so the feedback control image is a clear image in which the camera's focus is approximately aligned with the object. Therefore, even if the object is vibrating, the control unit can appropriately adjust the object's position to the target position based on the captured image.

As described above, the present invention provides an illuminated imaging device that can properly capture an image of an object even when the object is vibrating, and a position adjustment device using the same.

The effects and significance of the present invention will become clearer from the description of the embodiments shown below. However, the embodiment shown below is merely an example of how the present invention may be put into practice, and the present invention is in no way limited to the embodiments described below.

FIG. 1 is a side view schematically illustrating the configuration of a position adjustment system according to a first embodiment. FIG. 2 is a perspective view schematically illustrating the configuration of the position adjustment device according to the first embodiment. FIG. 3 is a block diagram showing the configuration of a circuit section of the position adjustment device according to the first embodiment. FIG. 4 is a schematic diagram showing a procedure for acquiring a captured image when an object is vibrating in the Z-axis direction according to a comparative example. FIG. 5 is a schematic diagram showing a procedure for acquiring a captured image when an object is vibrating in the Z-axis direction according to the first embodiment. FIG. 6 is a block diagram showing the configuration of a circuit section of a position adjustment device according to a modification of the first embodiment. Fig. 7A is a perspective view schematically illustrating a configuration of an object according to embodiment 2. Fig. 7B is a graph schematically illustrating vibrations of each edge according to embodiment 2. FIG. 8 is a perspective view schematically illustrating the configuration of a position adjustment device according to the second embodiment. FIG. 9 is a block diagram showing the configuration of a circuit section of a position adjustment device according to the second embodiment. FIG. 10 is a schematic diagram showing a procedure for acquiring a captured image according to the second embodiment. FIG. 11 is a side view schematically illustrating the configuration of a position adjustment system according to the third embodiment. FIG. 12 is a block diagram showing the configuration of a circuit section of a position adjustment device according to the fourth embodiment. FIG. 13 is a schematic diagram showing a procedure for acquiring a captured image according to the fourth embodiment. FIG. 14 is a diagram schematically illustrating a configuration example in which the illuminated imaging device according to the fifth embodiment is applied to a microscope.

However, the drawings are for illustrative purposes only and do not limit the scope of the invention.

Embodiments of the present invention will now be described with reference to the drawings. For convenience, the following drawings are labeled with mutually orthogonal X, Y, and Z axes. The positive direction of the Z axis is the height direction of the position adjustment system 1.

<Embodiment 1>
In the embodiment 1 described below, an illuminated imaging device 2a (see FIG. 3) is configured by a projection unit 40, an acceleration sensor 30 (detection unit), a camera 50 (camera unit), an imaging processing unit 113 (camera unit), a vibration analysis circuit 111 (analysis unit), and a drive circuit 112.

Figure 1 is a side view schematically showing the configuration of the position adjustment system 1.

The position adjustment system 1 includes a room 1a, a position adjustment device 2, and a robot 10. The room 1a is installed on the ground 3 and configured to prevent external light from entering the room 1a. The position adjustment device 2 and the robot 10 are located within the room 1a. In embodiment 1, when the position adjustment device 2 and the robot 10 are used, all lights within the room 1a are turned off except for the illumination light from the projection unit 40, making the room 1a a dark room. In other words, the room 1a is a dark environment, dark enough that the camera 50 cannot capture an image. By installing the position adjustment device 2 in a space where natural light is blocked, such as a dark environment, the influence of natural light can be suppressed when adjusting the position of the object T1, as described below.

The position adjustment device 2 comprises a support base 21, a drive unit 22, an installation unit 23, an acceleration sensor 30, a projection unit 40, and a camera 50.

The support base 21 is placed on the ground 3. The drive unit 22 is placed on the upper surface of the support base 21, and moves the installation unit 23 placed on the upper surface of the drive unit 22 in the X-axis and Y-axis directions, and rotates it about an axis parallel to the Z-axis direction. The drive unit 22 is an XYθ stage. The installation unit 23 is a flat member. An operator or another robot places the object T1 near the center of the upper surface 23a of the installation unit 23. The object T1 is, for example, a semiconductor substrate.

An acceleration sensor 30 is installed near the end of the upper surface 23a of the installation section 23. The acceleration sensor 30 detects vibrations of the installation section 23 and the object T1. In embodiment 1, the acceleration sensor 30 is required to be able to detect vibrations in at least the Z-axis direction.

The projection unit 40 is a light source that emits illumination light in a predetermined wavelength band. The projection unit 40 is, for example, an LED light source that emits monochromatic visible light. The projection unit 40 projects the illumination light onto an area that includes at least the object T1 on the installation unit 23. The projection unit 40 may be equipped with an optical system (lens, etc.) for limiting the projection area of the illumination light. The camera 50 is configured to capture visible light and includes a CMOS image sensor or a CCD image sensor. The camera 50 captures an image of the object T1 installed on the top surface 23a of the installation unit 23 and outputs imaging information indicating the integrated amount of light received by each pixel.

The robot 10 comprises a drive unit 11, a support shaft 12, a horizontal drive unit 13, an arm 14, and a gripping unit 15.

The drive unit 11 is installed on the ground 3 and moves the vertically extending support shaft 12 in the Z-axis direction and rotates it about an axis parallel to the Z-axis direction. The horizontal drive unit 13 is installed at the upper end of the support shaft 12 and moves the horizontally extending arm 14 in the horizontal direction. The gripper 15 is installed on the underside of the tip of the arm 14 and is configured to be able to grip various types of chips.

The robot 10 drives the drive unit 11 and horizontal drive unit 13 to move the gripper 15 onto a chip placed in the chip storage area, and drives the gripper 15 to grip the chip. The robot 10 drives the horizontal drive unit 13 to move the gripper 15 onto the object T1 placed on the placement unit 23, and drives the gripper 15 to release the gripped chip and place the chip on the object T1. The robot 10 sequentially places the chips on the object T1.

When the robot 10 places a chip on the object T1 in this way, if the object T1 is not positioned appropriately, the chip will be placed in an inappropriate position. Therefore, based on the image information from the camera 50, the drive unit 22 moves the installation unit 23 in the X-axis and Y-axis directions and rotates the installation unit 23 about an axis parallel to the Z-axis direction so that the object T1 is positioned appropriately.

Figure 2 is a perspective view schematically showing the configuration of the position adjustment device 2.

Camera 50 captures edges E1 and E2 of object T1. Edge E1 is the edge on the positive side of the X-axis of the top surface of object T1, and edge E2 is the edge on the negative side of the Y-axis of the top surface of object T1. The imaging direction of camera 50 is the negative direction of the Z-axis. The position and focal length of camera 50 are set so that the focal position of camera 50 in the Z-axis direction coincides with the positions of edges E1 and E2 of object T1 installed on installation unit 23.

In the captured image acquired by the camera 50, the position of the installation unit 23 is adjusted by the drive unit 22 so that edge E1 overlaps with line L1 indicating the appropriate position of edge E1, and edge E2 overlaps with line L2 indicating the appropriate position of edge E2. As a result, the position of the object T1 in the X-axis direction, Y-axis direction, and rotational position about the Z-axis are each adjusted to the target positions.

Figure 3 is a block diagram showing the configuration of the circuit section of the position adjustment device 2.

The position adjustment device 2 has a circuit configuration including an image acquisition unit 110 and a control unit 120. The image acquisition unit 110 is composed of a vibration analysis circuit 111, a drive circuit 112, and an image capture processing unit 113.

Based on the detection signal from the acceleration sensor 30, the vibration analysis circuit 111 estimates the period during which the focus of the camera 50 is approximately aligned with the object T1, and outputs a trigger to drive the drive circuit 112 during the estimated period. The specific operation of the vibration analysis circuit 111 will be described later with reference to Figures 4 and 5. The drive circuit 112 drives the projection unit 40 at the timing when the trigger is output from the vibration analysis circuit 111, causing the projection unit 40 to project illumination light. The image capture processing unit 113 processes the image capture information output from the camera 50 to obtain an image for feedback control, and outputs the obtained image to the control unit 120.

The control unit 120 detects the positions of edges E1 and E2 based on the captured image acquired by the image processing unit 113, and drives the drive unit 22 so that edges E1 and E2 align with lines L1 and L2, respectively (see Figure 2).

When the ground 3 (see Figure 1) shakes due to vibrations from various devices installed in room 1a (see Figure 1), the vibrations of the ground 3 are transmitted to object T1 via support base 21, drive unit 22, and installation unit 23, causing object T1 to vibrate. In this case, as shown by the white arrow in Figure 3, if object T1 vibrates in the Z-axis direction, the positions of edges E1 and E2 will deviate from the focal position of camera 50 in the Z-axis direction. As a result, the captured image acquired by image capture processing unit 113 will become unclear, making it impossible to properly adjust the position of object T1 based on the captured image.

In contrast, in this embodiment, the vibration analysis circuit 111 determines the position of the object T1 in the Z-axis direction based on the detection signal of the acceleration sensor 30. Then, the vibration analysis circuit 111 outputs a trigger to the drive circuit 112 when the positions of the edges E1 and E2 of the object T1 approximately align with the focal position of the camera 50. As a result, when the edges E1 and E2 of the object T1 come to the focal position of the camera 50, the object T1 is illuminated by the illumination light from the projection unit 40, and the captured image acquired by the image capture processing unit 113, as described below, becomes clear.

Figures 4 and 5 are schematic diagrams showing the procedures for acquiring captured images in the comparative example and embodiment 1, respectively, when the object T1 is vibrating in the Z-axis direction.

In the example shown in Figures 4 and 5, since the object T1 is made of the same material, the entire object T1 vibrates in unison in the Z-axis direction. Furthermore, one frame period of the camera 50 includes multiple vibrations, and the Z-axis position H1 of edges E1 and E2 coincides with the focal position H0 of the camera 50 approximately four times. The camera 50 is maintained in an exposure state during one frame period, and outputs the integrated amount of light received by each pixel during one frame period as imaging information. The imaging processing unit 113 acquires one captured image from the imaging information based on one frame.

Here, typically, vibrations that can occur in the object T1 in the position adjustment system 1 of Figure 1 are approximately 100 Hz or higher. Meanwhile, a typical camera 50 operates at 30 fps to 60 fps, with the length of one frame being approximately 16 milliseconds to approximately 33 milliseconds. Therefore, one frame of a typical camera 50 contains approximately 1.6 to 3.3 vibration waves. In other words, one frame contains both an in-focus state in which the Z-axis position H1 of edges E1 and E2 is approximately aligned with the focal position H0 of the camera 50, and an out-of-focus state other than the in-focus state.

As shown in Figure 4, in the comparative example, the light projection intensity of the projection unit 40 is maintained constant during the frame period. Therefore, illumination light is always projected onto the object T1 during the frame period. Therefore, in addition to the image of the object T1 in the focused state shown by the solid-line frame, each pixel of the camera 50 also receives the image of the object T1 in the out-of-focus state shown by the dashed-line frame. Therefore, the accumulated amount of light at each pixel is mixed with so-called out-of-focus light. Therefore, in the comparative example, the captured image M0 formed based on one frame of imaging information is an unclear image.

As shown in Figure 5, in embodiment 1, the projection unit 40 is driven on/off depending on the positions of edges E1 and E2. Specifically, the vibration analysis circuit 111 (see Figure 3) analyzes the detection signal of the acceleration sensor 30 using Fourier analysis or the like to obtain the Z-axis position Ht of the upper surface 23a of the installation unit 23. The vibration analysis circuit 111 adds the known height h of the object T1 to the obtained position Ht to obtain the position H1 of edges E1 and E2 of the object T1.

The vibration analysis circuit 111 estimates the period P1 during which the position H1 of the edges E1 and E2 is approximately aligned with the focal position H0 of the camera 50. The vibration analysis circuit 111 stores the focal position H0 in advance. If the depth of field of the camera 50 (the distance on one side from the focal position) is δ, then the period P1 is the period during which the following equation (1) is satisfied:

|H1-H0|≦δ…(1)

The vibration analysis circuit 111 analyzes the vibration pattern in the Z-axis direction based on the detection signal from the acceleration sensor 30, and from the analyzed vibration pattern, estimates the period in which the above equation (1) is satisfied as the period P1 of the focused state.

The vibration analysis circuit 111 then outputs a trigger to the drive circuit 112 during the estimated period P1. The drive circuit 112 drives the projection unit 40 to project illumination light onto the object T1 during the period P1 when the trigger is input. As a result, illumination light is projected onto the object T1 when edges E1 and E2 of the object T1 are near the focal position H0 of the camera 50. On the other hand, the vibration analysis circuit 111 does not output a trigger to the drive circuit 112 outside of the period P1. If no trigger is input, the drive circuit 112 causes the projection unit 40 to stop projecting illumination light. As a result, illumination light is not projected onto the object T1 when edges E1 and E2 of the object T1 are not near the focal position H0 of the camera 50.

Thus, in the focused state, as shown by the solid-line frame, the image of the focused object T1 is mainly incident on each pixel of the camera 50. In other words, in the out-of-focus state, since the object T1 is not illuminated by the illumination light and the room 1a is a dark room, almost no out-of-focus image is incident on each pixel of the camera 50. Therefore, in the case of embodiment 1, the captured image M1 formed based on one frame of imaging information is a clear image.

<Effects of First Embodiment>
As described above, according to the first embodiment, the following effects are achieved.

Based on the detection signal from the acceleration sensor 30 (detection unit), the illuminated imaging device 2a (see FIG. 3) estimates the period P1 during which the camera 50 is approximately focused on the object T1, and captures an image M1 for feedback control using illumination light during the estimated period P1. The control unit 120 then drives the drive unit 22 based on the captured image M1 to adjust the position of the object T1 to the target position. With this configuration, as described with reference to FIG. 5, the captured image M1 is captured using illumination light during the period P1 during which the camera 50 is approximately focused on the object T1. Therefore, even if the object T1 is vibrating, the captured image M1 for feedback control can be properly captured, and the control unit 120 can properly adjust the position of the object T1 to the target position based on the captured image M1.

As explained with reference to Figure 5, the image acquisition unit 110 projects illumination light from the projection unit 40 onto an area on the installation unit 23 that includes at least the object T1 during period P1, and causes the projection unit 40 to stop projecting illumination light outside period P1. With this configuration, ON/OFF control of the illumination light can suppress blurring of the captured image caused by vibration.

As shown in Figure 3, the detection unit that detects vibrations of the object T1 is an acceleration sensor 30 installed in the installation unit 23. With this configuration, vibrations of the object T1 can be easily detected.

As mentioned above, typical vibrations that can occur in the object T1 are approximately 100 Hz or higher, and a typical camera 50 operates at 30 to 60 fps. In this case, as shown in Figures 4 and 5, one frame includes both in-focus and out-of-focus states. In contrast, in embodiment 1, the image of the object T1 is incident on each pixel of the camera 50 only when it is in-focus, so even if one frame includes both in-focus and out-of-focus states, the captured image M1 formed based on the imaging information of one frame is a clear image. Therefore, the object T1 can be properly positioned at the target position based on the captured image M1.

<Modification of the First Embodiment>
In the first embodiment, the acceleration sensor 30 is used to detect the vibration state of the object T1, but in this modified example, a TOF (Time Of Flight) sensor 60 is used.

Figure 6 is a block diagram showing the configuration of the circuit section of the position adjustment device 2 in this modified example.

Compared to embodiment 1 shown in FIG. 3, the position adjustment device 2 of this modified example includes a TOF sensor 60 instead of the acceleration sensor 30. The TOF sensor 60 is installed, for example, on the underside of the camera 50. The TOF sensor 60 projects pulsed light in the negative Z-axis direction and receives the pulsed light reflected from the top surface of the object T1. The TOF sensor 60 detects the distance from the TOF sensor 60 to the top surface of the object T1 based on the time difference between the emission and reception of the pulsed light. The vibration analysis circuit 111 analyzes the vibration of the object T1 in the Z-axis direction based on the distance from the TOF sensor 60 to the object T1, and obtains the position H1 of the edges E1 and E2 of the object T1.

In this modified example, as in embodiment 1, the vibration analysis circuit 111 estimates the period P1 during which the position H1, which changes in response to vibration, approximately aligns with the focal position H0 of the camera 50, and outputs a trigger to the drive circuit 112 during the estimated period P1. The drive circuit 112 drives the projection unit 40 to project illumination light onto the object T1 during the period P1 when the trigger is input. As a result, as in embodiment 1, the captured image M1 formed based on one frame of imaging information is a clear image. Therefore, the control unit 120 can appropriately adjust the position of the object T1 to the target position based on the acquired captured image M1.

In addition, in this modified example, a TOF sensor 60 that measures the distance to the object T1 is used as the detection unit that detects vibrations of the object T1. This allows for an inexpensive configuration for detecting vibrations of the object T1. Furthermore, the TOF sensor 60 can directly measure vibrations near the edges E1 and E2, thereby improving the measurement accuracy of vibrations in the measurement object compared to indirectly measuring vibrations of the edges E1 and E2 by detecting vibrations of the installation unit 23, as in embodiment 1.

<Embodiment 2>
In the first embodiment, the object T1 is made of the same material, so when vibration occurs, the entire object T1 vibrates in the Z-axis direction as a whole. In contrast, in the second embodiment, the object T1 is made of a plurality of different materials, and each part of the different materials vibrates with a different phase.

In embodiment 2, the illuminated imaging device 2a (see Figure 9) is composed of projection units 41, 42, TOF sensors 61, 62 (detection units), cameras 51, 52 (camera units), imaging processing units 113, 133 (camera units), vibration analysis circuits 111, 131 (analysis units), and drive circuits 112, 132.

Figure 7(a) is an oblique view schematically showing the configuration of the object T1 according to embodiment 2.

In embodiment 2, object T1 is composed of portions T11 and T12 made of different materials. Edge E1 is the edge on the portion T11 side, and edge E2 is the edge on the portion T12 side. As such, when portions T11 and T12 are made of different materials, the speeds of vibrations transmitted to portions T11 and T12 are different, and therefore, even if the same vibration is applied from the ground 3, the phases of the vibrations at edges E1 and E2 are different.

Figure 7(b) is a graph schematically showing the vibration of each edge E1, E2 in embodiment 2.

The vibration waveforms of edges E1 and E2 are shown by solid and dashed lines, respectively. In this example, the vibration waveforms of edges E1 and E2 have the same shape but different phases. In this way, if portions T11 and T12 of object T1 vibrate at different phases, when an image is captured as in embodiment 1 above, one of edges E1 or E2 will be unclear in the captured image. Therefore, in embodiment 2, as shown below, vibrations are detected for portions T11 and T12, and an image is generated based on the imaging information obtained from portions T11 and T12, respectively.

Figure 8 is an oblique view schematically showing the configuration of the position adjustment device 2 relating to embodiment 2.

Compared to embodiment 1 in Figure 2, the position adjustment device 2 of embodiment 2 includes projection units 41, 42 and cameras 51, 52 instead of projection unit 40 and camera 50. Cameras 51, 52 have the same configuration as camera 50. Furthermore, the position adjustment device 2 of embodiment 2 includes TOF sensors 61, 62 and filters 71, 72. TOF sensors 61, 62 have the same configuration as TOF sensor 60 shown in the modified example of embodiment 1. The other configurations of embodiment 2 are the same as those of embodiment 1.

TOF sensor 61 is installed on the underside of camera 51 and detects the distance from TOF sensor 61 to the vicinity of edge E1. TOF sensor 62 is installed on the underside of camera 52 and detects the distance from TOF sensor 62 to the vicinity of edge E2. Projector 41 is an LED light source that emits illumination light in a first wavelength band, and projector 42 is an LED light source that emits illumination light in a second wavelength band different from the first wavelength band. The first wavelength band is, for example, a red light wavelength band, and the second wavelength band is, for example, a blue light wavelength band. Both cameras 51 and 52 capture the entire object T1. Filter 71 is a bandpass filter for camera 51 that transmits light in the first wavelength band and blocks light other than the first wavelength band. Filter 72 is a bandpass filter for camera 52 that transmits light in the second wavelength band and blocks light other than the second wavelength band.

Figure 9 is a block diagram showing the configuration of the circuit section of the position adjustment device 2 in embodiment 2.

Compared to embodiment 1 shown in Figure 3, the position adjustment device 2 of embodiment 2 has a circuit configuration including a vibration analysis circuit 131, a drive circuit 132, and an image capture processing unit 133. The image acquisition unit 110 of embodiment 2 is composed of the vibration analysis circuit 111, the drive circuit 112, the image capture processing unit 113, the vibration analysis circuit 131, the drive circuit 132, and the image capture processing unit 133.

The vibration analysis circuit 111 analyzes the vibration in the Z-axis direction near edge E1 based on the distance from the TOF sensor 61 to the vicinity of edge E1, and from the analysis results, estimates the period during which the focus of the camera 51 is approximately aligned with edge E1 based on the above equation (1), and outputs a trigger to drive the drive circuit 112 during the estimated period. As a result, when edge E1 is approximately aligned with the focal position of the camera 51, edge E1 is illuminated by the illumination light from the projection unit 41.

Similarly, the vibration analysis circuit 131 analyzes the vibration in the Z-axis direction near edge E2 based on the distance from the TOF sensor 62 to the vicinity of edge E2, and from the analysis results, estimates the period during which the focus of the camera 52 is approximately aligned with edge E2 based on the above equation (1), and outputs a trigger to drive the drive circuit 132 during the estimated period. As a result, when edge E2 is approximately aligned with the focal position of the camera 52, edge E2 is illuminated by the illumination light from the projection unit 42.

The camera 51 is equipped with a filter 71 that transmits only light in the first wavelength band, so the camera 51 receives only illumination light in the first wavelength band from the projection unit 41 and outputs imaging information. The imaging processing unit 113 processes the imaging information output from the camera 51 to obtain an image M11 for feedback control, and outputs the obtained image M11 to the control unit 120. The image M11 is an image in which the edge E1 is clear.

Similarly, camera 52 is equipped with a filter 72 that transmits only light in the second wavelength band, and therefore camera 52 receives only illumination light in the second wavelength band from projection unit 42 and outputs imaging information. The imaging processing unit 133 processes the imaging information output from camera 52 to obtain an image M12 for feedback control, and outputs the obtained image M12 to control unit 120. The image M12 is an image in which edge E2 is clear.

The control unit 120 extracts the line of edge E1 from the captured image M11 and extracts the line of edge E2 from the captured image M12. The control unit 120 then combines the extracted image of edge E1 with the extracted image of edge E2 to obtain a captured image M10 that includes only edges E1 and E2. The control unit 120 drives the installation unit 23 so that the line of edge E1 in the captured image M10 coincides with line L1 and the line of edge E2 in the captured image M10 coincides with line L2.

Figure 10 is a schematic diagram showing the procedure for acquiring captured images M11, M12, and M10 in embodiment 2.

As described above, edges E1 and E2 vibrate in the Z-axis direction at different phases. The projection unit 41 projects illumination light of a first wavelength onto object T1 during period P1, when the focal position of camera 51 is approximately aligned with edge E1. As a result, an image of object T1 in a focused state, as indicated by the solid-line frame, is incident on each pixel of camera 51. Therefore, an image M11 in which edge E1 is clearly visible is acquired based on one frame of imaging information from camera 51.

Similarly, the projection unit 42 projects illumination light of the second wavelength onto the object T1 during a period P2 when the focal position of the camera 52 is approximately aligned with the edge E2. As a result, an image of the object T1 in a focused state, as indicated by the solid-line frame, is incident on each pixel of the camera 52. Therefore, an image M12 in which the edge E2 is clearly visible is acquired based on one frame of imaging information from the camera 52.

In this way, the control unit 120 generates an image M10 based on an image M11 in which the edge E1 is clear and an image M12 in which the edge E2 is clear, and appropriately adjusts the position of the object T1 to the target position based on the image M10.

<Effects of the Second Embodiment>
As described above, according to the second embodiment, the following effects are achieved.

In embodiment 2, as in embodiment 1 above, it is possible to obtain clear images M11 and M12 of edges E1 and E2, and to properly adjust the position of object T1 to the target position.

Furthermore, filter 71 blocks light outside the wavelength band of the illumination light from projection unit 41 from reaching camera 51, and filter 72 blocks light outside the wavelength band of the illumination light from projection unit 42 from reaching camera 52. Filter 71 prevents unwanted light outside the wavelength band of the illumination light from projection unit 41 from entering camera 51 not only during period P1 but also outside period P1. Filter 72 prevents unwanted light outside the wavelength band of the illumination light from projection unit 42 from entering camera 52 not only during period P2 but also outside period P2. Therefore, blurring of captured images M11, M12, and M10 caused by vibration can be reliably suppressed.

<Embodiment 3>
In the first embodiment, the room 1a is set to be a dark room, whereas in the third embodiment, the room 1a is illuminated with illumination light of a predetermined color.

As in embodiment 1, in embodiment 3, the illuminated imaging device 2a (see Figure 12) is composed of a projection unit 40, an acceleration sensor 30 (detection unit), a camera 50 (camera unit), an imaging processing unit 113 (camera unit), and a vibration analysis circuit 111 (analysis unit).

Figure 11 is a side view schematically showing the configuration of the position adjustment system 1 relating to embodiment 3.

Compared to embodiment 1 of FIG. 1, the position adjustment system 1 of embodiment 3 includes a lighting device 1b and a filter 70. The lighting device 1b is installed in room 1a. The lighting device 1b emits, for example, yellow illumination light. As a result, the interior of room 1a is illuminated with yellow illumination light. The projection unit 40 is, for example, an LED light source that emits illumination light in the red or blue wavelength band. The filter 70 is a bandpass filter that transmits light in the wavelength band of the illumination light from the projection unit 40 and blocks light outside the wavelength band of the illumination light from the projection unit 40 for the camera 50. As a result, the illumination light from the lighting device 1b does not enter the imaging surface of the camera 50.

<Effects of the Third Embodiment>
5, in the third embodiment, illumination light is projected from the projection unit 40 during a period P1 in which the position H1 of the edges E1 and E2 is substantially aligned with the focal position H0 of the camera 50. This allows a clear captured image M1 to be acquired, similar to the first embodiment.

Furthermore, the filter 70 blocks light other than the wavelength band of the illumination light from the projection unit 40 from reaching the camera 50. The wavelength band of the illumination light from the projection unit 40 is set to a wavelength band different from the wavelength band of the light used to illuminate the room 1a in which the position adjustment device 2 is installed. This allows the illumination light from room 1a to be removed by the filter 70, thereby suppressing blurring that occurs in the captured image M1 due to the illumination light from room 1a.

In semiconductor manufacturing, rooms 1a are used that are lit from the inside with monochromatic visible light, such as yellow rooms, so that workers can work there. Even in this case, the influence of light from the lighting device 1b that illuminates the interior of the room 1a can be suppressed, allowing a clear captured image M1 to be obtained.

<Fourth Embodiment>
In the first embodiment, the camera 50 is in an exposure state for the entire period of one frame. In contrast to this, in the fourth embodiment, the projection unit 40 is always turned on, and the camera 50 is in an exposure state when the edges E1 and E2 are substantially aligned with the focal position H0 of the camera 50. In the fourth embodiment, a camera capable of switching the exposure state within one frame is used as the camera 50.

In embodiment 4, the illuminated imaging device 2a (see Figure 12) is also composed of a projection unit 40, an acceleration sensor 30 (detection unit), a camera 50 (camera unit), an imaging processing unit 113 (camera unit), a vibration analysis circuit 111 (analysis unit), and a drive separation 112.

Figure 12 is a block diagram showing the configuration of the circuit section of the position adjustment device 2 in embodiment 4.

In embodiment 4, compared to embodiment 1 of Figure 3, the vibration analysis circuit 111 outputs a trigger to the image capture processing unit 113 when edges E1 and E2 are approximately aligned with the focal position H0 of the camera 50. The camera 50 is configured to be able to switch the exposure state within one frame in response to instructions from the image capture processing unit 113. The other configurations of embodiment 4 are the same as those of embodiment 1.

Figure 13 is a schematic diagram showing the procedure for acquiring a captured image M1 in embodiment 4.

In embodiment 4, the projection unit 40 is always on. The vibration analysis circuit 111 outputs a trigger to the image capture processing unit 113 when edges E1 and E2 are approximately aligned with the focal position H0 of the camera 50, i.e., during period P1. The image capture processing unit 113 sets the shutters of all pixels of the camera 50 to an exposed state using exposure control at the timing when the trigger is input, i.e., during period P1. On the other hand, outside of period P1, the image capture processing unit 113 sets the shutters of all pixels of the camera 50 to a non-exposed state using exposure control.

As a result, similar to embodiment 1, when edges E1 and E2 are approximately aligned with the focal position H0 of camera 50, an image of object T1 in focus is incident on each pixel of camera 50. On the other hand, when edges E1 and E2 are not approximately aligned with the focal position H0 of camera 50, an image of object T1 is not incident on each pixel of camera 50. Therefore, in embodiment 4 as well, the captured image M1 formed based on one frame of imaging information is a clear image.

<Effects of the Fourth Embodiment>
The image acquisition unit 110 controls the camera 50 to expose each pixel during the period P1, and controls the camera 50 not to expose each pixel outside the period P1. This allows the exposure control of the camera 50 to suppress blurring of the captured image M1 caused by vibration.

<Embodiment 5>
In the above-described first to fourth embodiments, the illuminated imaging device 2a is used in the position adjustment device 2. However, the device in which the illuminated imaging device is used is not limited to the position adjustment device, and the illuminated imaging device may also be used as appropriate in other devices that may be used in an environment in which vibrations may cause blurring in the captured image.

Figure 14 is a schematic diagram showing an example configuration when the illuminated imaging device 200 is applied to a microscope 4.

In this configuration example, the illuminated imaging device 200 is composed of a projection unit 210, an acceleration sensor 242 (detection unit), an imaging unit 220 (camera unit), an imaging processing unit 253 (camera unit), a vibration analysis circuit 251 (analysis unit), and a drive circuit 252.

An object T1 with an uneven surface is placed on a stage 241. A microscope 4 is placed on the object T1. The microscope 4 incorporates a projection unit 210, an imaging unit 220, and a half mirror 231. The projection unit 210 comprises a light source 211, a collimator lens 212, and an objective lens 221. The imaging unit 220 comprises an objective lens 221, a condenser lens 222, and an imaging element 223. The objective lens 221 is shared by the projection unit 210 and the imaging unit 220. The imaging unit 220, together with an imaging processing unit 253, constitutes a camera unit.

The light source 211 emits illumination light. The light source 211 is composed of, for example, a light-emitting diode (LED). The illumination light emitted from the light source 211 is converted into approximately parallel light by the collimator lens 212, reflected by the half mirror 231, and directed toward the object T1. The illumination light is then focused by the objective lens 221 and illuminates the object T1. The area illuminated by the illumination light need only include the shooting location. The light from the illuminated area is captured by the objective lens 221 as light for shooting. The light for shooting then passes through the half mirror 231 and is focused by the focusing lens 222 on the shooting surface of the image sensor 223. As a result, an image of the object T1 is formed on the shooting surface of the image sensor 223.

An acceleration sensor 242 for detecting vibrations is installed on the stage 241. Vibrations transmitted from an external vibration source to the object T1 via the stage are detected by this acceleration sensor 242. A signal from the acceleration sensor 242 is output to the vibration analysis circuit 251. The location of the object T1 to be photographed shakes due to the vibration. However, as in the first embodiment above, a trigger is output from the vibration analysis circuit 251 to the drive circuit 252 so that illumination light is irradiated onto the object T1 only during the period when that location coincides with the photographing focus (the focal position determined by the objective lens 221 and the condenser lens 222). As a result, only the image at the focal position is formed on the image sensor 223.

The imaging processing unit 252 processes the imaging information output from the imaging element 223 to acquire an image, and outputs the acquired image to, for example, an analysis processing unit for inspecting the state of the object T1. Alternatively, the imaging processing unit 252 may display the acquired image on a display unit such as a monitor.

<Effects of the Fifth Embodiment>
The configuration of the fifth embodiment also makes it possible to capture an image without blur, similar to the first to fourth embodiments.

When a person directly views the image of the object T1, the image sensor 223 may be omitted from the imaging unit 220. In other words, if the "retina of the human eye" is also considered to be the imaging unit, the illuminated imaging device of the present invention can be applied to a microscope even when observing directly with the eye.

In addition to the microscope shown in Figure 14, an illuminated imaging device with a similar configuration to the above can also be used for other imaging devices, such as imaging devices used for component inspection in vibration-affected environments.

In the configuration example of Figure 14, as in embodiment 4 above, the light-emitting unit 210 may constantly emit illumination light while controlling the exposure time of the image sensor 223 to obtain an in-focus image. This also makes it possible to obtain a clear image without blur. In the configuration example of Figure 14, other vibration detection means, such as a TOF sensor, may be used instead of the acceleration sensor 242.

<Other changes>
The configurations of the position adjustment system 1 and the position adjustment device 2 can be modified in various ways in addition to the configurations shown in the above embodiment and modified examples.

In the above-described first and fourth embodiments and the modified example of the first embodiment, the projection unit 40 was an LED light source that emitted monochromatic light, but it may also be an LED light source that emits white light. However, because the response frequency of an LED light source that emits monochromatic light is higher than the response frequency of an LED light source that emits white light, it is preferable that the LED light source used as the projection unit 40 be an LED light source that emits monochromatic light. When an LED light source that emits monochromatic light is used, the illumination light can be turned on and off in response to high-frequency vibrations.

In the above embodiments 1, 3, and 4, the acceleration sensor 30 is installed on the installation unit 23, and vibrations of the object T1 are indirectly detected by detecting vibrations of the installation unit 23. However, this is not limited to this. For example, if the moving object equipped with the device itself is the object T1 to be adjusted in position, the acceleration sensor 30 may be installed on the object T1. Furthermore, if the ground 3 hardly vibrates but the camera 50 vibrates, the acceleration sensor 30 may be installed on the camera 50.

In the above-described embodiment 4, the projection unit 40 is always lit, but as in embodiment 1, the lighting of the projection unit 40 may be controlled when the edges E1 and E2 are approximately aligned with the focal position H0 of the camera 50. This reliably prevents unwanted light from entering the imaging surface of the camera 50.

In the above-described embodiment 4, the projection unit 40 is always on, but if a lighting device 1b is installed in the room 1a, as in embodiment 3, the projection unit 40 may be omitted. That is, the lighting device 1b installed in the room 1a may be used in place of the projection unit 40 of the position adjustment device 2. In this case, illumination light from the lighting device 1b is always irradiated onto the object T1, and the exposure of the camera 50 is controlled, thereby enabling a clear captured image M1 to be obtained, as in embodiment 4.

In the above embodiments 1 to 4 and the modified example of embodiment 1, the position adjustment device 2 is equipped with cameras 50, 51, and 52. However, if cameras are used to control the position of the robot 10, the position adjustment device 2 does not need to be equipped with cameras 50, 51, and 52. In other words, of the multiple cameras used to control the position of the robot 10, a camera whose focal position is approximately aligned near the edge of the target object T1 may be used in place of cameras 50, 51, and 52 of the position adjustment device 2. In this case, the imaging processing unit of the position adjustment device 2 acquires the captured image using the imaging information of that camera.

In the above-described modified example of embodiment 1 and embodiment 2, TOF sensors 60, 61, and 62 that measure the distance to the edges E1 and E2 of the object T1 were used as the detection unit that detects vibrations of the object T1. However, the configuration for measuring the distance to the edges E1 and E2 of the object T1 is not limited to TOF sensors; an eddy current sensor or a capacitance sensor may also be used. In these cases, too, a configuration for detecting vibrations of the object T1 can be realized inexpensively. Furthermore, these configurations allow the positions of the edges E1 and E2 to be measured directly, thereby improving measurement accuracy.

In the second embodiment, the focal positions of cameras 51 and 52 were the same H0, but if the height of object T1 differs between the edges, the focal positions of cameras 51 and 52 are set to different positions. In this case, too, projection unit 41 is turned on during period P1 when edge E1 approximately aligns with the focal position of camera 51, and projection unit 42 is turned on during period P2 when edge E2 approximately aligns with the focal position of camera 52. Therefore, in this case too, it is possible to obtain captured image M11 in which edge E1 is clear, and captured image M12 in which edge E2 is clear.

In embodiment 2, another imaging processing unit may be provided upstream of the control unit 120 to generate captured image M10 by combining captured image M11 from the imaging processing unit 113 and captured image M12 from the imaging processing unit 133. Also, captured image M11 and captured image M12 do not necessarily have to be combined. In this case, the control unit 120 drives the installation unit 23 so that the line of edge E1 extracted from captured image M11 coincides with line L1, and the line of edge E2 extracted from captured image M12 coincides with line L2.

In embodiment 2, the vibrations of edge E1 and edge E2 have the same shape, and only the phases of the vibrations differ, but this is not limited to this, and the amplitudes and periods of the two vibrations may differ from each other. Also, while the timing of one frame period for cameras 51 and 52 is the same, they may be offset from each other.

In Figures 5, 10, and 13, the edge position of object T1 is illustrated as a sinusoidal waveform, but this is not limited thereto; the amplitude of the waveform may change over time. In this case, too, the vibration analysis circuit estimates the period during which the edge position of object T1 approximately aligns with the focal position of the corresponding camera. This effectively reduces blurring in the captured image caused by vibration.

In the above-described embodiments 1 to 4 and the modified example of embodiment 1, the projection units 40, 41, and 42 are configured to emit visible light, and the cameras 50, 51, and 52 are configured to capture visible light. However, this is not limited thereto, and the projection units 40, 41, and 42 may be configured to emit infrared light or ultraviolet light, and the cameras 50, 51, and 52 may be configured to capture the corresponding infrared light or ultraviolet light.

In the above-described embodiments 1 to 4 and the modified example of embodiment 1, the vibration analysis circuit 111 previously stored the focal positions of the cameras 50, 51, and 52. However, this is not limited to this. The focal positions of the cameras 50, 51, and 52 may be determined, for example, by moving the cameras at low speed in the Z-axis direction in a vibration-free state, fixing the camera position in a state where the edge of the target object T1 in the captured image is clearly visible, and using the position of the edge of the target object T1 at this time as the focal position of the camera.

In the above-described embodiments 1 to 4 and the modified example of embodiment 1, the imaging direction of cameras 50, 51, and 52 was the Z-axis direction, but this is not limited to this and the imaging direction may be tilted relative to the Z-axis direction. In this case, the vibration of object T1 in the imaging direction of the camera is analyzed in the vibration analysis circuit based on detection signals from the acceleration sensor, TOF sensor, etc.

In the above embodiments, if the optical design is such that the effective range of the focus on the XY plane is sufficiently small, vibrations in the X or Y axis can be treated in the same way as Z axis vibrations. In other words, illumination light only needs to be applied during the period when the edge falls within the effective range.

In addition, various modifications of the embodiments of the present invention are possible as appropriate within the scope of the technical ideas set forth in the claims.

(Additional Note)
The above description of the embodiments discloses the following techniques.

(Technology 1)
a projection unit that irradiates an object with illumination light;
a detection unit that detects vibrations of the object;
a camera unit having a focal point;
an analysis unit that estimates a period during which the focus of the camera is approximately aligned with the object based on the detection signal from the detection unit, and causes the projection unit to project the illumination light onto an area including the object during the period, and causes the projection unit to stop projecting the illumination light outside the period,
An illuminated imaging device characterized by:

(Technology 2)
a projection unit that irradiates an object with illumination light;
a detection unit that detects vibrations of an object;
a camera unit having a focal point;
an analysis unit that estimates a period during which the focus is approximately aligned with the object based on a detection signal from the detection unit,
controlling the camera so as to expose each pixel during the period, and controlling the camera so as not to expose each pixel outside the period;
An illuminated imaging device characterized by:

Technologies 1 and 2 use illumination light to capture images during a period when the camera's focus is approximately aligned with the object, resulting in clear images of the object when the camera's focus is approximately aligned with the object. Therefore, even if the object is vibrating, an image of the object can be captured accurately.

(Technology 3)
In the illuminated imaging device according to any one of the first and second techniques,
further comprising a filter that blocks light other than the wavelength band of the illumination light from reaching the camera.
An illuminated imaging device characterized by:

This technology can prevent unwanted light outside the wavelength band of the illumination light from entering the camera not only during the above-mentioned period but also outside of that period. This further reduces blurring of captured images caused by vibration.

(Technique 4)
In the illuminated imaging device described in Technology 3,
a wavelength band of the illumination light is set to a wavelength band different from a wavelength band of light used to illuminate a room in which the illuminated imaging device is installed;
An illuminated imaging device characterized by:

This technology allows room lighting to be filtered out, thereby reducing blurring of captured images caused by room lighting.

(Technology 5)
In the illuminated imaging device according to any one of techniques 1 to 4,
The detection unit is an acceleration sensor installed on the installation unit or the object.
An illuminated imaging device characterized by:

This technology makes it easy to detect vibrations in an object.

(Technology 6)
In the illuminated imaging device according to any one of techniques 1 to 4,
The detection unit is a device for measuring the distance to the object.
An illuminated imaging device characterized by:

(Technology 7)
In the illuminated imaging device described in Technology 6,
The detection unit is a TOF sensor.
An illuminated imaging device characterized by:

This technology allows for inexpensive implementation of a configuration for detecting vibrations of an object. Furthermore, the TOF sensor allows for direct measurement of the object's position, improving the accuracy of measuring the object's position.

(Technology 8)
a placement unit on which an object is placed;
a driving unit that drives the installation unit to change the position of the object;
An illuminated imaging device according to any one of techniques 1 to 7;
a control unit that drives the drive unit using the captured image obtained by the illuminated imaging device as a feedback control image to adjust the position of the object to a target position,
A position adjustment device characterized by:

This technology uses an illuminated imaging device according to any one of technologies 1 to 7, so the feedback control image is a clear image in which the camera's focus is approximately aligned with the object. Therefore, even if the object is vibrating, the control unit can appropriately adjust the object's position to the target position based on the captured image.

2 Position adjustment device 2a, 200 Illuminated imaging device 22 Driving unit 23 Installation unit 30 Acceleration sensor (detection unit)
40, 41, 42, 210 Projection unit 50, 51, 52 Camera 60, 61, 62 TOF sensor (detection unit)
70, 71, 72 Filter 110 Image acquisition unit 111, 131, 251 Vibration analysis circuit (analysis unit)
113, 133, 253 Image capture processing unit 120 Control unit M1, M10, M11, M12 Captured image P1, P2 Period T1 Object

Claims (8)

a projection unit that irradiates an object with illumination light;
a detection unit that detects vibrations of the object ;
a camera unit having a focal point;
an analysis unit that estimates a period during which the focus is approximately aligned with the object based on a detection signal from the detection unit,
During the period, the projection unit projects the illumination light onto an area including the object, and outside the period, the projection unit stops projecting the illumination light.
An illuminated imaging device characterized by: a projection unit that irradiates an object with illumination light;
a detection unit that detects vibrations of the object ;
a camera unit having a focal point;
an analysis unit that estimates a period during which the focus is approximately aligned with the object based on a detection signal from the detection unit,
controlling the camera unit so as to expose each pixel during the period, and controlling the camera unit so as not to expose each pixel outside the period;
An illuminated imaging device characterized by: 3. The illuminated imaging device according to claim 1,
further comprising a filter that blocks light outside the wavelength band of the illumination light from reaching the camera unit .
3. The illuminated imaging device according to claim 1 or 2. 4. The illuminated imaging device according to claim 3,
a wavelength band of the illumination light is set to a wavelength band different from a wavelength band of light used to illuminate a room in which the illuminated imaging device is installed;
An illuminated imaging device characterized by: 3. The illuminated imaging device according to claim 1,
The detection unit is an installation unit on which the object is installed or an acceleration sensor installed on the object.
An illuminated imaging device characterized by: 3. The illuminated imaging device according to claim 1,
The detection unit is a device for measuring the distance to the object.
An illuminated imaging device characterized by: 7. The illuminated imaging device according to claim 6,
The detection unit is a TOF sensor.
An illuminated imaging device characterized by: a placement unit on which an object is placed;
a driving unit that drives the installation unit to change the position of the object;
The illuminated imaging device according to claim 1 or 2;
a control unit that drives the drive unit using the captured image obtained by the illuminated imaging device as a feedback control image to adjust the position of the object to a target position,
A position adjustment device characterized by: