JP2012068188A - Adjustment method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inclination detection method for easily detecting the inclined state of an imaging surface by simple configurations.SOLUTION: The adjustment method includes: an inclination detection process of detecting the inclined state of each of two imaging apparatuses; an inclination adjustment process of adjusting the inclination of the imaging apparatus; a location detection process of detecting the location of the imaging apparatus; a location adjustment process of adjusting the location of the imaging apparatus. The inclination detection process is characterized to image each of patterns set with equal intervals by successively changing the focal position of the imaging apparatus, and to set a pattern area by detecting the pattern position in the pickup image, and to detect the luminance value of each pixel in the pattern area, and to calculate luminance changing amounts between the pixels along the direction of inspection, and to calculate the integrated value of luminance changing amounts in each pattern area, and to detect the focal coincident position corresponding to the pickup image whose integrated value becomes the maximum, and to detect the inclined state of the imaging apparatus based on the focal coincident position.

Description

  The present invention relates to an adjustment method and the like.

  2. Description of the Related Art Conventionally, an inspection apparatus is known in which an inspection target is imaged by an imaging unit and the inspection target is inspected based on a captured image. In such an inspection apparatus, the incident light incident on the imaging means is imaged. When the optical axis of the incident light is inclined with respect to the measurement object, the entire area within one screen is accurately focused. I can not match. On the other hand, an apparatus that determines the tilt angle of the image sensor with respect to the illumination optical axis is known (see, for example, Patent Document 1).

In the inspection apparatus described in Patent Document 1, five tilt determination methods are shown as methods for detecting or adjusting the tilt of the image sensor.
That is, as the determination method 1, a plurality of sensors are arranged in the vicinity of the image pickup surface, the image pickup surface of the image pickup device is picked up, shape information such as the position and interval of the alignment mark is recognized from these picked-up images, A method of detecting is shown.
As a determination method 2, a method is provided in which a plurality of sensors for obtaining the height of the imaging surface are provided, and the tilt is detected by obtaining the heights of a plurality of locations on the imaging surface.
As a determination method 3, there is shown a method in which the tilt is adjusted by irradiating the imaging surface with light and changing the tilt angle of the imaging element in various directions and acquiring the maximum value of the output signal by the hill-climbing method.
As a determination method 4, a method is shown in which the luminance distribution of the imaging region is obtained from the output signal output from the imaging device, and the tilt is detected based on the deviation of these luminance distributions.
As a determination method 5, a pattern image is projected on the imaging surface, and a method of detecting the tilt by comparing the captured image and the pattern image is shown.

JP 2006-313143 A

  By the way, in the conventional tilt determination method 1 and determination method 2 as in the above-mentioned Patent Document 1, since it is necessary to separately provide a plurality of sensors, there are problems such as a complicated configuration and an increase in the number of parts. . Further, in the determination method 3, since it is necessary to change the attitude of the image sensor in every direction, detect an output signal, and search for the maximum output value in a hill-climbing method, the search time becomes long, and tilt adjustment is required. There is a problem that the time is long. Furthermore, in the determination method 4, there is a problem that when the light irradiated to the imaging surface is uneven in brightness, even if there is no tilt, it may be determined that there is tilt, and the accuracy of tilt detection is reduced. . Furthermore, the determination method 5 has a problem in that the accuracy of the tilt detection is lowered when the optical axis of the projection image light of the pattern image is inclined or deviated from the incident optical axis of the image sensor. .

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  [Application Example 1] An adjustment method for adjusting the optical axes of two imaging devices facing each other across a placement unit on which an inspection object is placed, and for each of the two imaging devices, An inclination detecting step for detecting an inclination state of the optical axis with respect to the mounting portion, and an inclination adjusting step for adjusting the inclination of the optical axis of the imaging device with respect to the mounting portion based on the inclination state detected in the inclination detecting step. And after the tilt adjustment step, based on the position detection step of detecting the position of the optical axis of the imaging device relative to the mounting portion and the position detected in the position detection step, the optical axis of the imaging device A position adjusting step for adjusting a position with respect to the placement unit, and the inclination detection step includes a pattern installation step for providing a pattern image in which patterns are formed at equal intervals on the placement unit, and the imaging device. Scorching The position is sequentially changed, the pattern image is captured at a predetermined distance interval, and a pattern imaging process for acquiring the captured image, and the position of the pattern in the captured image acquired by the pattern imaging process are detected, and A pattern area setting step for setting a pattern area including at least a part of the pattern from the captured image, and detecting a luminance value of each pixel in the pattern area and calculating a luminance change amount between the pixels along a predetermined inspection direction A luminance change amount calculating step, a change amount integrating step of calculating an integrated value of the luminance change amount in the pattern region, and the focal position corresponding to the captured image in which the integrated value in the pattern region is maximum. A focus coincidence detecting step for detecting the focus coincidence position, and the tilt state based on the focus coincidence position. Adjustment wherein the inclination detecting step of leaving, having, that.

The adjustment method of this application example is an adjustment method for adjusting the optical axes of two imaging devices that face each other across a placement unit on which an inspection object is placed, and the tilt detection is performed for each of the two imaging devices. A process, an inclination adjustment process, a position detection process, and a position adjustment process.
In the tilt detection step, a tilt state with respect to the mounting portion of the optical axis of the imaging device is detected.
In the inclination adjustment step, the inclination of the optical axis of the imaging device with respect to the placement portion is adjusted based on the inclination state detected in the inclination detection step.
In the position detection step, the position of the optical axis of the imaging device with respect to the placement unit is detected after the tilt adjustment step.
In the position adjustment step, the position of the optical axis of the imaging device with respect to the placement unit is adjusted based on the position detected in the position detection step.
Here, the inclination detection step includes a pattern installation step, a pattern imaging step, a pattern region setting step, a luminance change amount calculation step, a change amount integration step, a focus coincidence detection step, and an inclination detection step. .
According to this adjustment method, a pattern image is set on the placement unit in the pattern installation step, and a plurality of captured images in which the distance between the imaging device and the placement unit is changed is acquired in the pattern imaging step. In the pattern region setting step, a pattern region including at least a part of the pattern is set from within the captured image, and in the luminance change amount calculating step and the change amount integrating step, an integrated value of the luminance change amount in this pattern region is calculated. . Here, in a state where the focus position of the imaging device is coincident with the pattern image, the luminance change amount becomes large at the boundary (edge portion) of the pattern in the captured image. Therefore, the integrated value of the luminance change amount in the pattern region Also grows. Thus, when the integrated value of the luminance change amount of the pattern area is maximized, it indicates that the focal position of the imaging device matches one area of the pattern image corresponding to the pattern area. Then, the focal position of the imaging apparatus is detected as the focal position. That is, in the focus coincidence detection step, by detecting a captured image in which the integrated value of the luminance change amount is maximized for each of the plurality of pattern regions, the region corresponding to each pattern region on the pattern image and the focus of the imaging device It is possible to detect the focus matching position, which is the adjustment position of the imaging device or the adjustment position of the lens constituting the imaging device, which matches the position. In the tilt detection step, it is possible to easily detect the tilt state of the optical axis of the imaging device with respect to the placement unit based on these focal point matching positions.
In this way, since the inclination state of the optical axis of the imaging device with respect to the mounting unit is detected based on the captured image, for example, it is not necessary to separately provide a plurality of sensors and the inclination state detection process is easily performed with a simple configuration. be able to. In addition, a complicated operation such as tilting the imaging surface of the mounting unit or the imaging device in various directions is unnecessary, and a simple operation that only adjusts the focal position of the imaging device, that is, the imaging device is mounted on the mounting unit. The tilt state can be detected and the time required for the tilt state detection process can be shortened by simply moving the lens of the incident optical system of the image pickup device back and forth in one direction.
In addition, an imaging apparatus is provided for setting a plurality of pattern areas for a captured image of a pattern image, and detecting an inclination state of a predetermined area on the pattern image with respect to each pattern area based on an integrated value of the luminance change amount. On the other hand, it is not necessary to perform an operation such as irradiating light with no unevenness of brightness, and it is possible to easily detect a tilt state with high accuracy.
Furthermore, in this adjustment method, since the position detection process and the position adjustment process are performed for each of the two imaging devices, the optical axes of the two imaging devices can be aligned.

The block diagram which shows schematic structure of the test | inspection apparatus in this embodiment. The figure which shows an example of the pattern image in this embodiment. The figure which shows the imaging implementation position of the 1st imaging part in this embodiment, and a 2nd imaging part. The figure which shows a part of captured image data in this embodiment. The figure which showed the luminance variation | change_quantity in each pixel of the captured image data in this embodiment. It is a figure which shows the change of the luminance change integrated value at the time of changing the focus position of a 1st imaging part and a 2nd imaging part in the predetermined pattern area | region of the captured image data in this embodiment, (A) is a pattern The figure which shows the example of an area | region, (B) is a figure which shows the change curve of the luminance change integrated value in the pattern area | region shown by (A). The figure which shows an example of the inclination state display image in this embodiment. The flowchart of the adjustment method of the test | inspection apparatus in this embodiment. The flowchart which shows the inclination detection process in this embodiment.

Embodiments will be described with reference to the drawings.
FIG. 1 is a block diagram illustrating a schematic configuration of an inspection apparatus according to the present embodiment.

[Configuration of inspection equipment]
In FIG. 1, an inspection apparatus 1 is an apparatus that images an inspection target placed on a placement unit 2 from above and below in the Z direction and performs various inspections based on the captured image. The inspection apparatus 1 accurately inspects defects and the like based on captured images of, for example, an inspection apparatus for a display body such as a liquid crystal panel, an inspection apparatus for inspecting the structure of a structure such as a semiconductor wafer and the presence or absence of deposits. The present invention can be applied to various inspections other than an apparatus and a microscope for inspecting the detailed shape of an inspection object. The inspection device 1 includes a placement unit 2, a first imaging device 3, a second imaging device 4, and a control device 6. An inspection object and a pattern member 7 are placed on the placement unit 2.

The first imaging device 3 is provided above the placement unit 2 in the Z direction. The second imaging device 4 is provided below the placement unit 2 in the Z direction. The first imaging device 3 and the second imaging device 4 are opposed to each other with the placement unit 2 interposed therebetween.
The first imaging device 3 includes a first imaging unit 8 and a first advancing / retreating driving unit 9 serving as a focus adjusting unit that moves the first imaging unit 8 toward and away from the mounting unit 2.
The second imaging device 4 includes a second imaging unit 11 and a second advancing / retreating driving unit 12 as a focus adjusting unit that moves the second imaging unit 11 toward and away from the mounting unit 2.
The control device 6 controls the operation of the inspection device 1 as a tilt detection device. The control device 6 individually controls the placement unit 2, the first imaging device 3, and the second imaging device 4.

The placement unit 2 includes a pedestal 15, a first X-axis stage 16, a first Y-axis stage 17, a second X-axis stage 18, and a second Y-axis stage 19.
The first Y-axis stage 17 and the second Y-axis stage 19 are respectively disposed on the pedestal portion 15. A first X-axis stage 16 is disposed on the first Y-axis stage 17. A second X-axis stage 18 is disposed on the second Y-axis stage 19.
The inspection object and the pattern member 7 are placed on the first X-axis stage 16.
On the second X-axis stage 18, the first imaging device 3 is disposed.
The inspection object and the pattern member 7 placed on the first X-axis stage 16 can be moved in the X direction and the Y direction by the first Y-axis stage 17 and the first X-axis stage 16.

Similarly, the first imaging device 3 is configured to be movable in the X direction and the Y direction by the second Y axis stage 19 and the second X axis stage 18.
The placement unit 2 having the above configuration is connected to the control device 6. Then, the first Y-axis stage 17 and the second Y-axis stage 19 individually move in the Y direction based on commands from the control device 6. The first X-axis stage 16 and the second X-axis stage 18 also individually move in the X direction based on commands from the control device 6.
In the present embodiment, the pedestal 15, the first X-axis stage 16, and the first Y-axis stage 17 are each made of a material having optical transparency. Therefore, the inspection object and the pattern member 7 placed on the first X-axis stage 16 can be imaged by the second imaging device 4. Examples of the light transmissive material include glass and resin.

Here, the pattern member 7 used in the inclination detection method will be described. The pattern member 7 is made of a light transmissive material. The pattern member 7 is a plate-like member formed to have a uniform thickness dimension with a pattern image formed on the surface, for example. The pattern member 7 has a bottom surface that is formed into a smooth surface, and can be placed on the first X-axis stage 16 in a substantially tight contact state.
A pattern image 21 is formed on the surface of the pattern member 7, for example, as shown in FIG. In the present embodiment, the pattern image 21 has a plurality of circular patterns 22. In the pattern image 21, the plurality of circular patterns 22 are equally arranged in the X-axis direction and the Y-axis direction to form the pattern image 21.

Note that the pattern image 21 is not limited to the above configuration, and for example, an image in which a plurality of rectangular patterns are evenly arranged in the X-axis direction and the Y-axis direction may be used.
The pattern member 7 is provided with a reference pattern 23 at a substantially central portion. In the present embodiment, a cross pattern is adopted as the reference pattern 23. The reference pattern 23 is used when the optical axes of the first imaging unit 8 and the second imaging unit 11 are aligned.
In the present embodiment, a cross pattern is employed as the reference pattern 23, but the reference pattern 23 is not limited to this. As the reference pattern 23, for example, various polygons such as a rectangle and a star, an arbitrary shape such as a circular pattern 22, and an arbitrary pattern such as a pattern or a pattern including characters and symbols can be adopted.

  As shown in FIG. 1, the first imaging unit 8 is provided facing the mounting unit 2 from above in the Z direction, and mounts the inspection object and the pattern member 7 mounted on the mounting unit 2. An image is taken from above in the Z direction of the unit 2. The first imaging unit 8 includes a camera 26, an incident optical system 27, and a tilt adjusting unit 28. The incident optical system 27 guides incident light incident from the mounting unit 2 to the camera 26. The tilt adjusting means 28 adjusts the tilt angle of the camera 26 and the incident optical system 27. The camera 26 and the incident optical system 27 constitute an imaging unit. The first imaging unit 8 is held by an arm 29. The arm 29 can be moved forward and backward along the Z direction by the first advance / retreat drive unit 9, that is, can be moved toward and away from the placement unit 2. ing.

  The second imaging unit 11 is provided facing the mounting unit 2 from below in the Z direction. The second imaging unit 11 moves the inspection object and the pattern member 7 placed on the placement unit 2 through the pedestal unit 15, the first Y axis stage 17, and the first X axis stage 16 in the Z direction. The image is taken from below. The second imaging unit 11 includes a camera 31, an incident optical system 32, and a tilt adjusting unit 33. The incident optical system 32 guides incident light incident from the mounting unit 2 to the camera 31. The tilt adjusting means 33 adjusts the tilt angle of the camera 31 and the incident optical system 32. The camera 31 and the incident optical system 32 constitute an imaging unit. The second imaging unit 11 is held by an arm 34, and the arm 34 can be moved forward and backward along the Z direction by the second forward / backward drive unit 12, that is, can be moved toward and away from the mounting unit 2. ing.

  Although not shown, each of the camera 26 and the camera 31 includes an imaging surface in which a plurality of imaging elements are arranged in a matrix. When these imaging elements receive incident light, they generate an electrical signal corresponding to the amount of received light by photoelectric conversion processing. Then, the camera 26 and the camera 31 each output an electrical signal output from each imaging element in accordance with incident light to the control device 6 as captured image data.

  The incident optical system 27 and the incident optical system 32 are provided to face the mounting unit 2, respectively, and guide light incident from the mounting unit 2 to the imaging elements of the camera 26 and the camera 31. Each of the incident optical system 27 and the incident optical system 32 includes optical components such as a plurality of lenses, and these optical components are arranged such that the optical axis is orthogonal to the imaging surfaces of the camera 26 and the camera 31. Yes. Note that the incident optical system 27 and the incident optical system 32 may each include a focus adjustment mechanism that performs focusing by moving each optical component along the optical axis direction.

The inclination adjusting means 28 and the inclination adjusting means 33 are driven by control signals input from the control device 6, respectively. The tilt adjusting unit 28 tilts the camera 26 and the incident optical system 27, which are imaging units, at an angle corresponding to the signal. In addition, the tilt adjusting unit 33 tilts the camera 31 and the incident optical system 32 that are imaging units to an angle corresponding to the signal.
As described above, the first advance / retreat drive unit 9 holds the first imaging unit 8 via the arm 29. The second advance / retreat drive unit 12 holds the second imaging unit 11 via the arm 34.
The first advancing / retreating drive unit 9 holds the arm 29 so as to be able to advance and retreat in the Z-axis direction (the direction in which the arm 29 moves toward and away from the mounting unit 2). Advance and retract along the Z-axis direction. The second advancing / retreating drive unit 12 holds the arm 34 so as to be able to advance and retreat in the Z-axis direction (the direction in which the arm 34 moves toward and away from the placement unit 2). Advance and retract along the Z-axis direction.

In the present embodiment, the first advance / retreat drive unit 9 and the second advance / retreat drive unit 12 drive the arm 29 and the arm 34 to adjust the focus of the first imaging unit 8 and the focus of the second imaging unit 11. Illustrated. However, the adjustment method of the focus of the 1st imaging part 8 and the focus of the 2nd imaging part 11 is not limited to this.
As a focus adjustment method, for example, a method in which the first advance / retreat drive unit 9 or the second advance / retreat drive unit 12 directly moves the first imaging unit 8 or the second imaging unit 11 in the Z-axis direction may be employed. According to this configuration, since the arm 29 and the arm 34 can be omitted, vibration and the like can be prevented, and the first imaging unit 8 and the second imaging unit 11 can be driven more precisely.
Further, the optical components in the incident optical system 27 and the incident optical system 32 are advanced and retracted by the first advance / retreat drive unit 9 and the second advance / retreat drive unit 12, and the focus of the first imaging unit 8 and the second imaging unit 11 is placed. A method of matching the inspection object placed on 2 and the pattern member 7 can also be adopted.

The control device 6 controls the overall operation of the inspection device 1. The control device 6 performs detection of an inclination state of the first imaging unit 8 with respect to the mounting unit 2, correction of the inclination of the first imaging unit 8, inspection processing of the inspection object, and the like. In addition, the control device 6 also performs detection of an inclination state of the second imaging unit 11 with respect to the placement unit 2, correction of the inclination of the second imaging unit 11, inspection processing of the inspection object, and the like. For example, a general-purpose personal computer may be used as the control device 6.
As shown in FIG. 1, the control device 6 includes an input / output unit 41, an input operation unit 42, a storage unit 43, and an arithmetic processing unit 44.

  The input / output unit 41 is connected to the first imaging device 3, the second imaging device 4, and the placement unit 2. The input / output unit 41 outputs a control signal output from the arithmetic processing unit 44 to each of the first imaging device 3, the second imaging device 4, and the placement unit 2. Further, when the captured image data 46 (see FIGS. 3, 4, and 6) is input from the first imaging unit 8 or the second imaging unit 11, the input / output unit 41 converts the captured image data 46 into an arithmetic processing unit. 44. The input / output unit 41 includes a terminal to which an output device 47 such as a display or a printer can be connected, and outputs various processing results under the control of an arithmetic processing unit 44 described later.

The input operation unit 42 includes input means such as a keyboard and a mouse, for example, and outputs an operation signal corresponding to the operation content to the arithmetic processing unit 44 when the user operates the input means.
The storage unit 43 stores various data and programs. Examples of the storage unit 43 include a drive that drives a recording medium such as an HDD, a memory, a CD, and a DVD.
The arithmetic processing unit 44 is configured by an integrated circuit such as a CPU, and performs predetermined arithmetic processing by a program stored in the storage unit 43. As shown in FIG. 1, the program executed by the arithmetic processing unit 44 includes a focus control means 51, an inclination calculation means 52, an inclination correction means 53, an inspection means 54, and the like.

The focus control unit 51 performs autofocus processing and sets the reference positions of the first imaging unit 8 and the second imaging unit 11. Here, the autofocus process is not particularly limited. As the autofocus processing, for example, the first advancing / retreating driving unit 9 and the second advancing / retreating driving unit 12 are moved forward and backward while referring to the captured image data input from the first imaging unit 8 and the second imaging unit 11, and the captured image is captured. A so-called contrast detection method for detecting a point where the contrast of data is maximized may be employed. As an autofocus process, there is an active method for detecting the distance between the first imaging unit 8 or the second imaging unit 11 and the pattern member 7 placed on the placement unit 2 by irradiating infrared rays or the like. Can be employed. Then, a position where the first imaging unit 8 and the second imaging unit 11 are in focus with respect to the pattern member 7 on the placement unit 2 is set as a reference position.
In the present embodiment, during the autofocus process, the first advancing / retreating driving unit 9 and the second advancing / retreating driving unit 12 are driven, and the first imaging is performed at a position where the pattern member 7 on the placement unit 2 is in focus. Although the structure which moves the part 8 and the 2nd imaging part 11 is illustrated, it is not limited to this. For example, the first advance / retreat drive unit 9 and the second advance / retreat drive unit 12 are driven to move the first imaging unit 8 and the second imaging unit 11 to the center position of the displaceable range in the Z-axis direction. A configuration may be adopted in which focusing is performed by moving the lens of the incident optical system 32 forward and backward. In this case, the reference positions of the first imaging unit 8 and the second imaging unit 11 are set to the center position of the displaceable range in the Z-axis direction.
Furthermore, although the configuration in which the autofocus process is performed by the focus control unit 51 is illustrated, for example, a configuration in which the imaging control unit 61 described below has a function of performing the autofocus process may be used.

The tilt calculating means 52 obtains the tilt state (tilt) of the mounting unit 2 with respect to the optical axis of the incident optical system 27 of the first imaging unit 8 based on the captured image data 46 by the first imaging device 3. In addition, the tilt calculating means 52 obtains the tilt state (tilt) of the mounting unit 2 with respect to the optical axis of the incident optical system 32 of the second imaging unit 11 based on the captured image data 46 by the second imaging device 4.
The inclination calculation means 52 includes an imaging control means 61, a pattern area setting means 62, a luminance change amount calculation means 63, a change amount integration means 64, a focus coincidence detection means 65, and an inclination detection means 66. ing.

The imaging control means 61 generates a Z-axis control signal for moving the first imaging unit 8 and the second imaging unit 11 to a predetermined position, and uses the generated Z-axis control signal as the first advance / retreat drive unit 9 and the second advance / retreat unit. Output to the drive unit 12.
The imaging control unit 61 controls the first imaging unit 8 and the second imaging unit 11 to perform an imaging operation, and acquires captured image data 46 input from the first imaging unit 8 and the second imaging unit 11.
Here, the imaging control means 61 performs control to acquire the captured image data 46 by the first imaging unit 8 and the second imaging unit 11 as shown in FIG. FIG. 3 is a diagram illustrating the imaging execution positions of the first imaging unit 8 and the second imaging unit 11. That is, the imaging control unit 61 is centered on the reference position set by the focus control unit 51, and the first imaging unit 8 and the second imaging unit are within a preset range with respect to the ± Z direction from the reference position. 11 is moved. At this time, the imaging control unit 61 drives the first imaging unit 8 and the second imaging unit 11 at a preset driving amount (for example, 1 μm) interval, and the first imaging unit 8 and the second imaging unit at each position. The unit 11 is controlled to acquire the captured image data 46. Then, the imaging control unit 61 associates the acquired captured image data 46 with the position data of the first imaging unit 8 and the second imaging unit 11 corresponding to the captured image data 46, and can appropriately read the data to the storage unit 43. Remember.

  The pattern area setting unit 62 detects the position of the circular pattern 22 included in the captured image data 46 stored in the storage unit 43, and the coordinates of the captured image data 46 with respect to the pattern image 21 from the position data of these circular patterns 22. Detect position. That is, when imaging is performed by moving the first imaging unit 8 or the second imaging unit 11 in the Z-axis direction, the scale of each captured image data 46 is slightly different, and the circular pattern 22 is also arranged at a slightly different position. Image. Therefore, the pattern area setting means 62 first detects the position of the circular pattern 22 and sets the coordinate position with respect to the pattern image 21 from the position data of the circular pattern 22. That is, a coordinate position indicating which position in the pattern image 21 corresponds to each pixel of each captured image data 46 is set. Then, the pattern area setting unit 62 divides each captured image data 46 set with these coordinates into a plurality of pattern areas 71. Here, FIG. 4 is a diagram illustrating a part of the captured image data 46. The pattern area setting means 62 equally divides a plurality of square pattern areas 71 from the captured image data 46 so that one circular pattern 22 is included in one pattern area 71 as shown in FIG.

As shown in FIG. 5, the luminance change amount calculating unit 63 calculates the luminance change amount with respect to each pattern region 71 with respect to a predetermined inspection direction. FIG. 5 is a diagram showing the luminance change amount in each pixel of the captured image data 46.
The luminance change amount calculation unit 63 calculates the luminance change amount between pixels along a predetermined inspection direction. In the present embodiment, as shown in FIG. 5, the X-axis direction is set as the inspection direction, and the luminance change amount between a pair of pixels adjacent to the calculation target pixel of the luminance change amount is calculated along the X-axis direction. Specifically, the luminance change amount calculation means 63 assumes that the coordinates of the pixel for calculating the luminance change amount are (x, y) and the luminance change amount at this point (x, y) is K (x, y). Then, the luminance change amount is calculated by the following equation (1).

K (x, y) = abs (A (x-1, y) -A (x + 1, y)) (1)
In the above formula (1), A (x−1, y) and A (x + 1, y) are luminance values at the point (x−1, y) and the point (x + 1, y), respectively. That is, the luminance change amount calculation unit 63 detects the luminance value of a pair of pixels adjacent to the calculation target pixel along the inspection direction (X-axis direction), and calculates the absolute value of these luminance differences as the luminance change of the calculation target pixel. The quantity is K (x, y).
Also, the luminance change amount calculation means 63 performs a process of displaying a luminance change amount display image as shown in FIG. 5 using the luminance change amount K (x, y) for each pixel calculated here as a luminance value. Also good.

  The change amount integrating means 64 calculates the luminance change integrated value in the pattern region 71 by integrating the luminance change amount of the pixels included in each pattern region 71.

The focus coincidence detection unit 65 calculates the change amount integration unit 64 for a plurality of captured image data 46 acquired by setting the first imaging unit 8 and the second imaging unit 11 at a plurality of height positions. The integrated luminance change value of each pattern area 71 is read, and the focus coincidence position in these pattern areas 71 is detected.
Here, FIG. 6 is a diagram illustrating a change in the luminance change integrated value when the focal positions of the first imaging unit 8 and the second imaging unit 11 are changed in the predetermined pattern region 71 of the captured image data 46. . 6A is a diagram illustrating an example of the pattern region 71, and FIG. 6B is a diagram illustrating a change curve of the luminance change integrated value in the pattern region 71 illustrated in FIG. 6A.
As shown in FIG. 6, when the focal position of the first imaging unit 8 or the second imaging unit 11 is changed, the luminance change integrated value also changes.
That is, when the focal positions of the first imaging unit 8 and the second imaging unit 11 coincide with the area corresponding to the pattern area 71 of the pattern member (in focus), the outer periphery of the circular pattern 22 in the pattern area 71 Since no blur occurs at the edge, the amount of change in luminance increases at pixels sandwiching the outer peripheral edge, and the integrated value of luminance change also increases. On the other hand, when the focal position of the first imaging unit 8 or the second imaging unit 11 changes and the focus is shifted, blurring occurs at the outer peripheral edge of the circular pattern 22 in the pattern area 71, and the luminance change amount is also small. Become. In this case, the luminance change integrated value in the pattern area 71 is also reduced.
The focus coincidence detecting means 65 detects the point where the integrated luminance change value is maximized, so that the position where the first imaging unit 8 or the second imaging unit 11 is moved relative to the pattern area 71 is determined. Whether the focal position matches the pattern image, that is, the focal position is detected. In the example of FIG. 6, the focus coincidence detection unit 65 detects a position where the height position of the first image pickup unit 8 or the second image pickup unit 11 is “10” as the focus coincidence position with respect to the pattern region 71A, and A position where the height position of the first imaging unit 8 is “7” with respect to the region 71B is detected as a focus matching position.

The tilt detection unit 66 detects the tilt state (tilt) of the mounting unit 2 with respect to the incident optical axis of the first imaging unit 8 or the second imaging unit 11 based on the focal point matching position of each pattern region 71.
Specifically, the inclination detecting means 66 generates an inclination state display image 73 as shown in FIG. The tilt state display image 73 is an image in which rectangular areas having the same size as the pattern area 71 set by the pattern area setting unit 62 are evenly spread and colors corresponding to the focal point matching positions are displayed in these rectangular areas. .
Here, as in the example of FIG. 6, the focus matching position of the pattern region 71A is the reference position (height position “10”), and the height position of the focus matching position of the pattern region 71B is “7”. The mounting unit 2 is inclined in a direction away from the first imaging unit 8 and the second imaging unit 11 with respect to the incident optical axis of the first imaging unit 8 and the second imaging unit 11 with respect to the pattern region 71B. It can be judged. That is, as shown in FIG. 7, by displaying the focus coincidence position with respect to each pattern region 71, it is possible to easily determine the inclination state of the placement unit 2. In the present embodiment, the tilt detection unit 66 generates the tilt state display image 73 as shown in FIG. 7, but generates an image that displays the focus coincidence position with respect to each pattern region 71 as a specific numerical value, for example. May be.

The inclination correction means 53 generates an inclination correction signal for correcting the inclination of the first imaging unit 8 or the second imaging part 11 based on the detection result detected by the inclination detection means 66, and the inclination adjustment means 28 or inclination adjustment. It outputs to the means 33. For example, as illustrated in FIG. 6, when the region corresponding to the pattern region 71 </ b> B of the placement unit 2 is inclined in a direction away from the first imaging unit 8 or the second imaging unit 11, A tilt correction signal is generated so that the imaging surface corresponding to the pattern area 71B of the second imaging unit 11 is tilted to the placement unit 2 by a dimension corresponding to the focal point matching position, and the tilt adjustment unit 28 and the tilt adjustment unit 33 are generated. Output to.
Note that the inclination correction means 53 may be configured to generate an inclination correction signal and output it to the inclination adjustment means 28 or the inclination adjustment means 33 in accordance with a user's manual input.

  The inspection unit 54 inspects the inspection object placed on the placement unit 2 based on the captured image data 46 input from the first imaging unit 8 and the second imaging unit 11.

[Operation of inspection equipment]
An adjustment method in the inspection apparatus 1 will be described.
The adjustment method in the inspection apparatus 1 is a method in which the optical axis of the first imaging unit 8 and the optical axis of the second imaging unit 11 are aligned and the tilt of each of the first imaging unit 8 and the second imaging unit 11 is adjusted. is there.
FIG. 8 is a flowchart of the adjustment method of the inspection apparatus in the present embodiment.

The adjustment method in the inspection apparatus 1 includes a pattern installation step S1, an inclination detection step S2, an inclination adjustment step S3, a position detection step S4, and a position adjustment step S5.
In the pattern installation step S <b> 1, the pattern member 7 is placed on the placement unit 2 of the inspection apparatus 1. When the pattern image 21 is formed on the first X-axis stage 16 of the placement unit 2, the pattern setting step S1 may be omitted because the setting of the pattern image 21 has already been completed. .

Next, in the tilt detection step S2, the tilt detection step S2 shown in FIG. 9 is performed for each of the first imaging unit 8 and the second imaging unit 11.
As shown in FIG. 9, the tilt detection step S2 includes an autofocus step S201, a pattern imaging step S202, a pattern region setting step S203, a luminance change amount calculation step S204, a change amount integration step S205, and a focus coincidence detection. Step S206 and inclination detection step S207 are included.
In the autofocus step S201, the focus control means 51 of the control device 6 refers to the captured image data input from the first imaging unit 8 and the second imaging unit 11, and the first advance / retreat drive unit 9 and the second advance / retreat drive. The unit 12 is driven to move the first imaging unit 8 and the second imaging unit 11 to a reference position where the contrast of the captured image data is maximized.

Next, in the pattern imaging step S202, the tilt calculation means 52 of the control device 6 drives the first advance / retreat drive unit 9 and the second advance / retreat drive unit 12 by the imaging control means 61, and thereby the first imaging unit 8 and the second imaging unit. The unit 11 is advanced and retracted along the Z direction at 1 μm intervals at a height position within a predetermined range from the reference position, and the pattern image 21 is captured at each height position to obtain captured image data 46. In addition, the imaging control unit 61 stores the captured image data 46 obtained by imaging in the storage unit 43 in association with position data regarding the height position at which the captured image data 46 was captured.
Next, in the pattern area setting step S203, the inclination calculating unit 52 detects the position of each circular pattern 22 from each captured image data 46 acquired in the pattern imaging step S202 by the pattern area setting unit 62. Then, the pattern area setting unit 62 sets a coordinate position indicating which position in the pattern image 21 each pixel of each captured image data 46 is based on the position data of the circular pattern 22.
Then, the pattern area setting means 62 performs a process of dividing the captured image data 46 into a plurality of pattern areas 71 as shown in FIG.

Next, in the luminance change amount calculating step S204, the inclination calculating unit 52 sets the X axis direction as the inspection direction for each pattern region 71 set in the pattern region setting step S203 by the luminance change amount calculating unit 63, and The luminance change amount of each pixel is calculated using Equation (1). Further, the inclination calculation means 52 calculates the amount of change in luminance in each pixel for all the captured image data 46 acquired in the pattern imaging step S202 and all the pattern regions 71 set in the pattern region setting step S203. To do.
Next, in the change amount integrating step S205, the inclination calculating unit 52 integrates the luminance change amount calculated in the luminance change amount calculating step S204 by the change amount integrating unit 64 for each pattern region 71. The integrated luminance change value at 71 is calculated.
Next, in the focus coincidence detection step S206, the tilt calculation means 52 causes the focus coincidence detection means 65 to take a captured image that maximizes the luminance change integrated value calculated in the change amount integration step S205 for each pattern region 71. Data 46 is detected. Then, the focus coincidence detection unit 65 detects position data along the Z direction of the first image pickup unit 8 and the second image pickup unit 11 corresponding to the detected imaged image data 46 as a focus coincidence position with respect to the pattern region 71.

Next, in the tilt detection step S207, the tilt calculation unit 52 uses the first imaging unit 8 and the second imaging unit 8 based on the focus matching position for each pattern region 71 detected by the tilt detection unit 66 in the focus matching detection step S206. The inclination state of the mounting unit 2 with respect to the incident optical axis of the imaging unit 11 is detected, and an inclination state display image 73 as shown in FIG. 7 is generated.
Following the inclination detection step S2 shown in FIG. 9, in the inclination adjustment step S3 shown in FIG. 8, the inclinations of the first imaging unit 8 and the second imaging unit 11 are adjusted by the inclination adjustment means 28 and the inclination adjustment means 33. .

Next, in the position detection step S4, the reference pattern 23 (FIG. 2) of the pattern member 7 is imaged by each of the first imaging unit 8 and the second imaging unit 11. And the arithmetic processing part 44 detects the position with respect to the reference pattern 23 of the 1st imaging part 8 or the 2nd imaging part 11 based on an imaging result. Thereby, the positions of the first imaging unit 8 and the second imaging unit 11 with respect to the reference pattern 23 can be grasped.
Subsequently, in position adjustment process S5, the position of each optical axis of the 1st imaging part 8 and the 2nd imaging part 11 is adjusted.
The positions of the optical axes of the first imaging unit 8 and the second imaging unit 11 are implemented by positioning the reference pattern 23 of the pattern member 7 at approximately the center of the field of view of the camera 26 and the camera 31.
When the reference pattern 23 is displaced from the approximate center of the field of view of the camera 31, the position of the pattern member 7 relative to the camera 31 is changed by driving the first X-axis stage 16 and the first Y-axis stage 17.
On the other hand, when the reference pattern 23 is deviated from the approximate center of the field of view of the camera 26, the position of the camera 26 relative to the pattern member 7 is changed by driving the second X-axis stage 18 and the second Y-axis stage 19.
As described above, the optical axes of the first imaging unit 8 and the second imaging unit 11 can be aligned.

[Effects of inspection device]
As described above, in the inspection apparatus 1, the pattern image 21 is set on the placement unit 2 by the pattern setting process, and the height positions of the first imaging unit 8 and the second imaging unit 11 are changed by the imaging control unit 61. A pattern imaging process is performed in which the pattern image 21 is captured and the captured image data 46 is acquired. Then, the inclination calculating means 52 of the control device 6 performs a pattern area setting step of dividing the captured image data 46 into a plurality of pattern areas 71 by the pattern area setting means 62, and for each pixel in the captured image data 46. Then, the luminance change amount calculation unit 63 performs a luminance change amount calculation step to calculate the luminance change amount between the pixels along the inspection direction. Further, the change amount integrating means 64 performs a change amount integrating step for calculating a luminance change integrated value for each pattern region 71. Thereafter, the focus coincidence detection unit 65 acquires the captured image data 46 having the maximum luminance change integrated value for each pattern region 71, and the first imaging unit 8 and the second imaging unit 46 corresponding to the captured image data 46. A focus coincidence detection process is performed in which the height position of the imaging unit 11 is detected as a focus coincidence position. And the inclination detection means 66 implements the inclination detection process which detects the inclination state of the mounting part 2 with respect to the incident optical axis of the 1st imaging part 8 or the 2nd imaging part 11 based on this focus coincidence position.

For this reason, the first image capturing unit 8 and the second image capturing unit 11 are respectively set to the pattern regions 71 on the basis of the focus matching positions detected based on the luminance change amounts of the pattern regions 71 of the captured image data 46. The inclination state of the mounting portion 2 with respect to the incident optical axis can be detected. Therefore, the tilt position and the tilt amount in the placement unit 2 can be detected in detail for each region, and an accurate tilt detection process can be performed. For example, even when light having uneven luminance is irradiated on the pattern image 21, light having the same intensity is irradiated while the first imaging unit 8 and the second imaging unit 11 are moved in the Z-axis direction. If so, the amount of light applied to the area corresponding to each pattern area 71 is constant. Therefore, it is possible to accurately detect the tilt state of the mounting portion 2 without being affected by uneven brightness.
Further, since the tilt detection process is performed based on the captured image data 46, it is not necessary to use a plurality of sensors, for example, and the cost of the inspection apparatus can be reduced. Further, since the first imaging unit 8 and the second imaging unit 11 are moved in the Z direction and imaging is performed by the first imaging unit 8 and the second imaging unit 11, for example, the first imaging unit 8 and the second imaging unit 11 are used. Compared to a method of performing imaging by tilting in various directions with respect to both the X-axis direction and the Y-axis direction, the processing time can be significantly shortened, and the tilt detection process can be speeded up.

The pattern image 21 includes a circular pattern 22 that is arranged at equal intervals in the X-axis direction and the Y-axis direction.
For this reason, the luminance change amount calculating means 63 can easily calculate the luminance change amount between the pixels with the X-axis direction as the inspection direction. Even when the inspection direction is set in the Y-axis direction, the luminance change amount can be calculated. That is, in the present embodiment, the luminance change integrated value is calculated using only the X-axis direction as the inspection direction, and the focus matching position is obtained based on the luminance change integrated value. For example, in the pattern image 21 having the circular pattern 22, It may be configured to calculate the amount of change in luminance for each of the X-axis direction and the Y-axis direction and calculate the integrated value of luminance change based on the amount of change in luminance. In this case, the focus matching position can be detected more accurately. The tilt state can be inspected better.

The inspection apparatus 1 includes a focus control unit 51, and performs an autofocus process and sets a reference position in an autofocus process. In the pattern imaging process, the captured image data 46 is acquired by moving the first imaging unit 8 and the second imaging unit 11 within a predetermined range centered on the reference position.
That is, the inspection apparatus 1 mainly detects a minute inclination state of the mounting unit 2 with respect to the incident optical axis of the first imaging unit 8 or the second imaging unit 11, and in this case, a small size centered on the reference position is used. The focus coincidence position of each pattern region 71 exists within the range. In such a case, in the method of moving the first imaging unit 8 and the second imaging unit 11 by 1 μm, for example, with respect to the entire movable range and acquiring the captured image data 46, the quantity of the captured image data 46 increases. However, the processing time and processing load also increase. On the other hand, as described above, by setting only the predetermined range centered on the reference position as the inspection target, the quantity of the captured image data 46 is reduced, and the processing time and the processing load can be reduced.
In addition, when the inclination state of the mounting unit 2 is large, the user can visually check the first imaging unit using the inclination state detection method according to the present embodiment after being corrected to a certain inclination state in advance. 8 or the inclination state of the mounting unit 2 with respect to the incident optical axis of the second imaging unit 11 is detected.

Then, in the pattern area setting step, the pattern area setting means 62 equally divides the captured image data 46 into rectangular pattern areas 71.
For this reason, the luminance change integrated value is calculated for all the pattern regions 71 in the captured image data 46, and the focus matching position is detected based on the luminance change integrated value. The tilt angle can be detected in more detail, and the tilt detection accuracy can be improved.

Further, in the inclination detection step, the inclination detection unit 66 generates an inclination state display image 73 that displays the focus coincidence position corresponding to each pattern region 71.
For this reason, for example, by outputting and displaying the tilt state display image 73 on the output device 47, the user can easily confirm the tilt position and the tilt amount in the placement unit 2. Therefore, it is possible to satisfactorily support the inclination correction work for the first imaging unit 8 and the mounting unit 2 of the second imaging unit 11 by the user.
Further, the inclination correcting means 53 outputs an inclination correction signal to the inclination adjusting means 28 based on the focus coincidence position and the inclination state display image 73 with respect to each pattern region 71, and the inclination adjusting means 28 of the first imaging unit 8. The tilt state has been corrected. For this reason, even when the mounting unit 2 is inclined with respect to the incident optical axis of the first imaging unit 8 or the second imaging unit 11, the first imaging unit 8 or the The tilt state of the second imaging unit 11 can be corrected.

[Other Embodiments]
The present invention is not limited to the embodiments described above, and various improvements and modifications can be made within the scope of achieving the object of the present invention.

  For example, in the present embodiment, a configuration in which a plate-like member having an equal thickness as the pattern member 7 is placed in close contact with the first X-axis stage 16 of the placement unit 2 is exemplified. The member 7 may be formed in a film shape, and may be affixed and fixed on the placement unit 2. Furthermore, a configuration in which the pattern image 21 is directly formed on the placement unit 2 may be employed.

The inspection apparatus 1 can be any object as long as it performs a predetermined process based on an image captured by an imaging unit. For example, a pixel of a display body such as a liquid crystal panel In addition to a pixel defect detection device that detects defects based on captured images, a structural defect detection device that detects structural defects of foreign objects such as semiconductor wafers, adhesion of foreign matter, etc. based on captured images, and detailed inspection of inspection objects The present invention can also be applied to a microscope or the like.
Furthermore, although the configuration in which the tilt detection device is included in the inspection device is illustrated, a configuration in which the tilt detection device is provided separately may be used.

  Furthermore, the first image pickup unit 8 and the second image pickup unit 11 are provided with the inclination adjustment unit 28 and the inclination adjustment unit 33, and the inclination adjustment unit 28 and the inclination adjustment unit 33 are driven by the control of the control device 6 to perform the first image pickup. Although the configuration in which the tilt state of the unit 8 and the second imaging unit 11 is changed is illustrated, for example, a configuration in which the tilt of the first imaging unit 8 and the second imaging unit 11 is directly changed manually may be employed. Even in this case, the tilt state display image 73 is output to the output means, for example, so that the tilt adjustment can be easily performed while referring to the tilt state display image 73.

  In addition, the incident optical system 27 and the incident optical system 32 may have a configuration without focus adjustment, or may have a configuration with focus adjustment as in the present embodiment. Further, in the present embodiment, the first image pickup unit 8 and the second image pickup unit 11 are moved forward and backward by the first advance / retreat drive unit 9 and the second advance / retreat drive unit 12, so that a plurality of captured images corresponding to each height position are obtained. Although an example of acquiring the data 46 has been shown, for example, the focus adjustment mechanism in the incident optical system 27 or the incident optical system 32 functions as the focus adjustment unit of the present invention, and a plurality of optical components are moved by moving the focus adjustment mechanism. The captured image data 46 corresponding to the height position may be acquired, or the focus adjustment unit may be configured by the first advance / retreat drive unit 9, the second advance / retreat drive unit 12, and the focus adjustment mechanism.

  Furthermore, in the present embodiment, an example in which the pattern area 71 is set so that one circular pattern 22 is included in one pattern area 71 with respect to the pattern image 21 having the circular pattern 22 as shown in FIG. Although shown, for example, the pattern region 71 may be set so that two or more circular patterns 22 are included. Even when a pattern image in which a pattern other than the circular pattern 22 is formed is used, the pattern region 71 may be set so that at least a part of the pattern is included. Furthermore, in the above, an example in which the captured image data 46 is equally divided into a plurality of pattern areas 71 is shown, but the areas of the pattern areas 71 may be different from each other. For example, in the central region of the captured image data 46, processing may be performed in which the area of the pattern region 71 is increased and the area of the pattern region 71 is decreased toward the outer peripheral portion. The inclination state in the vicinity of the peripheral edge portion of the mounting portion 2 can be detected with high accuracy.

  Further, in the pattern area setting step, the pattern area setting means 62 is configured to set the pattern area 71 obtained by equally dividing the captured image data 46. However, the present invention is not limited to this. For example, the pattern area setting unit 62 may perform a process of cutting out only a predetermined position in the captured image data 46 as the pattern area 71. In this case, for example, by setting the pattern regions 71 at the four corners of the captured image data 46 and a total of nine places between these four corners, it is possible to detect in which inclination direction the mounting unit 2 is inclined. Is possible.

  The luminance change amount calculation unit 63 calculates the luminance change amount between pixels along the inspection direction with the X axis direction as the inspection direction. For example, the Y axis direction may be the inspection direction. The direction that intersects the direction may be set as the inspection direction. Furthermore, as described above, the luminance change amount with respect to the X-axis direction and the luminance change amount with respect to the Y-axis may be calculated, and the tilt state may be detected based on these luminance change amounts. The relative inclination state of the mounting unit 2 and the first imaging unit 8 and the second imaging unit 11 can be detected.

  The luminance change amount calculation unit 63 uses the absolute value of the luminance difference between two pixels adjacent to the calculation target pixel as the luminance change amount. For example, the luminance change amount calculation unit 63 calculates the absolute value of the luminance difference between the calculation target pixel and one adjacent pixel. The luminance change amount may be used, and a larger value of the absolute values of the luminance differences between the calculation target pixel and the two adjacent pixels may be used as the luminance change amount.

  In the tilt state detection method, in the pattern imaging process, the first imaging unit 8 and the second imaging unit 11 are moved in a range from a preset lower set value to an upper set value to obtain the captured image data 46. Although it is acquired, in the focus coincidence detection step, if it is detected that the focus coincidence position is the lower set value or the upper set value, there is a possibility that an accurate focus coincidence position cannot be obtained. In this case, returning to the pattern imaging process again, the movement range of the first imaging unit 8 and the second imaging unit 11 is expanded, that is, the value of the lower setting value is decreased, the value of the upper setting value is increased, and the captured image data 46 is increased. You may use the method of acquiring. With such a configuration, it is possible to detect a more appropriate focus coincidence position, and thus the tilt state of the mounting unit 2 with respect to the incident optical axis of the first imaging unit 8 or the second imaging unit 11 can be more accurately detected. It can be detected well.

  DESCRIPTION OF SYMBOLS 1 ... Inspection apparatus, 2 ... Mounting part, 3 ... 1st imaging device, 4 ... 2nd imaging device, 6 ... Control apparatus, 7 ... Pattern member, 8 ... 1st imaging part, 9 ... 1st advance / retreat drive part, DESCRIPTION OF SYMBOLS 11 ... 2nd imaging part, 12 ... 2nd advance / retreat drive part, 16 ... 1st X-axis stage, 17 ... 1st Y-axis stage, 18 ... 2nd X-axis stage, 19 ... 2nd Y-axis stage, 21 ... Pattern image, 22 ... Circular pattern, 23 ... reference pattern, 26 ... camera, 27 ... incident optical system, 28 ... tilt adjusting means, 31 ... camera, 32 ... incident optical system, 33 ... tilt adjusting means.

Claims (1)

An adjustment method for adjusting the optical axes of two imaging devices facing each other across a placement portion on which an inspection object is placed,
For each of the two imaging devices,
An inclination detection step of detecting an inclination state of the optical axis of the imaging device with respect to the mounting portion;
Based on the tilt state detected in the tilt detection step, a tilt adjustment step of adjusting the tilt of the optical axis of the imaging device with respect to the placement unit;
A position detecting step for detecting a position of the optical axis of the imaging device with respect to the mounting portion after the tilt adjusting step;
A position adjustment step of adjusting the position of the optical axis of the imaging device relative to the mounting portion based on the position detected in the position detection step;
The tilt detection step includes
A pattern installation step for providing a pattern image in which a pattern is formed at equal intervals on the placement section,
A pattern imaging step of sequentially changing the focal position of the imaging device, capturing the pattern image at predetermined distance intervals, and acquiring the captured image;
A pattern region setting step of detecting a position of the pattern in the captured image acquired by the pattern imaging step and setting a pattern region including at least a part of the pattern from the captured image;
A luminance change amount calculating step of detecting a luminance value of each pixel in the pattern region and calculating a luminance change amount between the pixels along a predetermined inspection direction;
A change amount integrating step of calculating an integrated value of the luminance change amount in the pattern region;
A focus matching detection step of detecting the focus position corresponding to the captured image with the maximum integrated value in the pattern area as a focus matching position;
An inclination detection step of detecting the inclination state based on the focus coincidence position,
An adjustment method characterized by that.

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