JP6072511B2 - Position adjustment apparatus and position adjustment method - Google Patents

Description

  The present invention relates to a position adjusting device and a position adjusting method for adjusting a relative positional relationship between an imaging lens and an imaging element.

  In recent years, with the rapid progress of high resolution camera modules, there is a demand for mounting technology that adjusts the relative positional relationship between the imaging lens and the imaging element with high accuracy.

  Here, conventionally, a technique for adjusting the relative positional relationship between the imaging lens and the imaging element based on the outer shape and appearance of the camera module is known. As an example, Patent Document 1 discloses a technique in which an actuator is picked up by an image pickup device, and the relative positional relationship between the optical axis of the image pickup lens and the center of the image pickup element is adjusted based on the gloss and color thereof. Has been.

  However, in recent years, it is required to perform adjustment with higher accuracy than the adjustment based on the outer shape and appearance of the camera module as disclosed in Patent Document 1.

  In Patent Document 2, the camera module main body is arranged in an adjustment frame, the position of the camera module main body is adjusted based on the image signal of the image sensor for inspection obtained from the camera module main body, and the camera module main body remains adjusted. A technique for adhering and fixing to the adjustment frame is disclosed.

  Patent Document 3 discloses a technique for imaging a measurement chart and adjusting the relative positional relationship between an imaging lens and an imaging element based on mark position information of the captured image. In Patent Document 3, the orientation of the image sensor is controlled by imaging the measurement chart using a reference lens and an image sensor, and the measurement chart is imaged using the image lens and the reference image sensor. The attitude of the imaging lens is controlled.

  In each of the technologies disclosed in Patent Documents 2 and 3, an image sensor that uses an image signal to adjust the relative positional relationship between the imaging lens and the image sensor, but is not mounted on a finished camera module is used. It is necessary to use it. As a result, the techniques disclosed in Patent Documents 2 and 3 may complicate the camera module manufacturing process. When the manufacturing process of the camera module becomes complicated, an error may occur in the relative positional relationship between the imaging lens and the imaging device when the imaging device (which should be mounted on the finished camera module) is mounted on the imaging lens. Concerned.

  Therefore, a technique for directly adjusting the relative positional relationship between the imaging lens and the imaging device while performing imaging using only the imaging device mounted on the completed camera module as the imaging device is known. Such techniques are disclosed in Patent Documents 4 and 5, for example.

  In Patent Document 4, an imaging signal for each measurement position is acquired while moving the imaging lens to a plurality of measurement positions set along the optical axis direction of the imaging lens, and the optical axis of the imaging element is obtained from the imaging signal. A technique for automatically adjusting the direction position and the inclination of two axes orthogonal to the optical axis is disclosed.

  Patent Document 5 discloses a technique for quantitatively detecting the tilt of an image sensor from image data of a chart obtained by imaging a measurement chart moving along the optical axis direction of an imaging lens a plurality of times with a fixed image sensor. Has been.

  Both the techniques disclosed in Patent Documents 4 and 5 are techniques that can perform high-precision adjustment suitable for the configuration of the camera module in order to adjust the inclination of the image plane of the imaging lens with high precision. I can say that.

JP 2012-27063 A (published February 9, 2012) JP 2011-175019 A (published September 8, 2011) JP2011-133509A (released on July 7, 2011) JP 2009-302837 A (released on December 24, 2009) JP 2006-319544 A (published on November 24, 2006) JP 2005-86659 A (published March 31, 2005)

  In any of the techniques disclosed in Patent Documents 4 and 5, it is necessary to acquire the relationship of the resolving power of the camera module to the focus shift position of the imaging lens, that is, the defocus characteristic. As a result, in any of the techniques disclosed in Patent Documents 4 and 5, it is necessary to perform movement control to each focus shift position and obtain an output signal of the image sensor for each focus shift position. In particular, in a camera module that needs to adjust the relative positional relationship between the imaging lens and the imaging device with high accuracy, the amount of data handled at the time of adjustment becomes enormous.

  As a result, in the techniques disclosed in Patent Documents 4 and 5, there is a problem that when adjusting the relative positional relationship between the imaging lens and the imaging element with high accuracy, the measurement time and thus the adjustment time become long. Occur.

  The present invention has been made in view of the above problems, and an object of the present invention is to enable adjustment of the relative positional relationship between the imaging lens and the imaging element with high accuracy and in a short time. An adjustment device and a position adjustment method are provided.

により、上記撮像レンズに対する、上記撮像素子の受光面の、該撮像レンズの光軸方向への傾き量θを求める傾き量演算部を備えていることを特徴としている。
In order to solve the above problem, a position adjustment device according to an aspect of the present invention is a position adjustment device that adjusts the relative positional relationship between an imaging lens and an imaging element, and includes a plurality of measurement objects, Each of the obtained images of the plurality of measurement objects obtained with reference to the center of the position adjustment image that is an image obtained by imaging the plurality of measurement objects using the imaging lens and the imaging element . A plurality of measurement objects, each of which includes a positional deviation adjustment unit that adjusts a relative positional deviation between the imaging lens and the imaging element based on an asymmetry of a relationship between an image height and a contrast. The plurality of measurement objects are arranged so as to appear in any one of a plurality of image heights in the position adjustment image, and for each corresponding image height, the object distance to the imaging lens is different. But the same The center of the sphere constituting the spherical surface is positioned on a straight line obtained by extending the optical axis of the imaging lens, the radius of the sphere is R, and the position adjustment image With respect to the optical axis of the imaging lens, the position on the spherical surface corresponding to the center and the position on the spherical surface corresponding to any image height other than the center having the same contrast as the center of the position adjustment image When the separation distance in the vertical direction is dx, the positional deviation adjusting unit is represented by the following formula (1).

Thus, an inclination amount calculation unit for obtaining an inclination amount θ of the light receiving surface of the imaging element with respect to the imaging lens in the optical axis direction of the imaging lens is provided .

により、上記撮像レンズに対する、上記撮像素子の受光面の、該撮像レンズの光軸方向への傾き量θを求めることを特徴としている。 A position adjustment method according to an aspect of the present invention is a position adjustment method for adjusting a relative positional relationship between an imaging lens and an imaging element in order to solve the above-described problem, and includes the imaging lens and the imaging element. The relationship between the image height and the contrast of each of the obtained plurality of measurement object images with reference to the center of the position adjustment image, which is an image obtained by imaging a plurality of measurement objects using Based on the asymmetry, the relative positional deviation between the imaging lens and the imaging device is adjusted so that each of the plurality of measurement objects is captured at any one of a plurality of image heights in the position adjustment image. In addition, for each of the corresponding image heights, the object distance to the imaging lens is different , the plurality of measurement objects are arranged on the same spherical surface, and the center of the sphere constituting the spherical surface is arranged. The imaging lens The optical axis is positioned on a straight line, the radius of the sphere is R, and the position on the spherical surface corresponding to the center of the position adjustment image has the same contrast as the center of the position adjustment image. When the distance in the direction perpendicular to the optical axis of the imaging lens from the position on the spherical surface corresponding to an arbitrary image height other than the center is dx,
The following mathematical formula (1)

Thus, an inclination amount θ of the light receiving surface of the image pickup element with respect to the image pickup lens in the optical axis direction of the image pickup lens is obtained.

  According to one embodiment of the present invention, it is possible to adjust the relative positional relationship between an imaging lens and an imaging element with high accuracy and in a short time.

It is a top view which shows schematic structure of the position adjustment apparatus which concerns on embodiment of this invention. It is sectional drawing which shows the schematic structural example of a camera module. It is the figure which looked at the arrangement of a plurality of detection patterns in the direction of the optical axis of an imaging lens. It is a graph explaining the method of calculating | requiring dx. It is the figure which showed the correlation between the chart for alignment mark measurement shown in FIG. 3, dx, and inclination amount (theta).

(Configuration of camera module)
FIG. 2 is a cross-sectional view illustrating a schematic configuration example of the camera module.

  A camera module 200 shown in FIG. 2 includes an imaging lens 201 and an imaging element 202.

  The imaging lens 201 performs imaging of an object to be imaged by the camera module 200. The imaging lens 201 has three lenses, but the number of lenses in the imaging lens may be two or less or four or more. The imaging lens 201 is accommodated in the lens barrel 203, but may be accommodated in a lens holder (not shown) instead of the lens barrel 203, or the imaging lens 201 is accommodated in the lens barrel 203. The lens barrel 203 may be accommodated in the lens holder.

  The imaging element 202 receives light that has passed through the imaging lens 201 by the light receiving surface 204 and converts the received light into an electrical signal. As the imaging device 202, a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) can be used.

  The camera module 200 performs imaging of an object using the imaging lens 201 and the imaging element 202.

  Examples of the camera module 200 include a known camera module that includes an imaging lens 201 and an imaging element 202. The camera module 200 includes a cover glass that protects the light receiving surface 204 of the image sensor 202, a mechanism that realizes an autofocus function by displacing the imaging lens 201 in the direction of the optical axis 201a (of the imaging lens 201), and an imaging lens. A mechanism (not shown) that realizes a camera shake correction function by displacing 201 in a direction perpendicular to the optical axis 201a may be further provided.

  In the camera module 200, for example, the imaging lens 201 and the imaging element 202 are arranged on a straight line in which the center 204c of the light receiving surface 204 of the imaging element 202 extends the optical axis 201a of the imaging lens 201, and the light receiving surface 204 is light. Ideally, it should be arranged perpendicular to the axis 201a.

  In the position adjustment device according to the following embodiment, in the camera module 200, in order to realize the ideal positional relationship between the imaging lens 201 and the imaging element 202, the imaging lens 201 and the imaging element 202 have a relative relationship. The positional relationship is adjusted.

(Configuration of position adjustment device)
FIG. 1 is a top view showing a schematic configuration of the position adjusting apparatus according to the present embodiment.

  The position adjustment apparatus shown in FIG. 1 includes a plurality of detection patterns (measurement objects) 101 and a position deviation adjustment unit 102. The positional deviation adjustment unit 102 includes an image acquisition unit 103, a dx calculation unit 104, an inclination amount calculation unit 105, a member displacement unit 106, and an axis deviation amount calculation unit 107.

  One detection pattern 101 is, for example, one alignment mark provided on the measurement chart. Although detailed illustration is omitted for the sake of convenience, each detection pattern 101 includes, for example, a plurality of parallel lines provided substantially perpendicular to the optical axis 201a. Various lines such as those provided in the horizontal direction, those provided in the vertical direction, or combinations thereof can be applied to the plurality of lines.

  Here, each of the plurality of detection patterns 101 is reflected in one of a plurality of image heights in a position adjustment image described later, and the object distance with respect to the imaging lens 201 is different for each corresponding image height. Is arranged.

  More specifically, the plurality of detection patterns 101 are arranged on the same spherical surface 101s, and the center 101c of the sphere constituting the spherical surface 101s is located on a straight line obtained by extending the optical axis 201a.

  In the present specification, “image height” is an index indicating the height from the center of a captured image, and in particular, the horizontal direction (x in the direction perpendicular to the optical axis 201a to the center of the image. (Direction).

  FIG. 3 is a diagram showing the arrangement of the plurality of detection patterns 101 in the direction of the optical axis 201a.

  As shown in FIG. 3, each detection pattern 101 is formed on a measurement chart 301 with an alignment mark, for example. Preferably, the measurement chart 301 with alignment mark is arranged so as to be part of the spherical surface 101s.

  As shown in FIG. 1, the plurality of detection patterns 101 are arranged on a spherical surface 101s of a sphere whose center 101c is on a straight line obtained by extending the optical axis 201a when viewed from above. On the other hand, as shown in FIG. 3, the plurality of detection patterns 101 are aligned in the x direction when viewed in the direction of the optical axis 201a. In other words, the plurality of detection patterns 101 have the same height in the vertical direction.

  In the present embodiment, the symbols x-2, x-1, x0, x1, and x2 are attached to the plurality of detection patterns 101 in order from the one on the left side of FIG.

  In this embodiment, an example in which there are five detection patterns 101 is described. However, the number of detection patterns 101 is not limited to five, and may be four or less, or six or more. There may be.

  The plurality of detection patterns 101 are imaged by the imaging lens 201. At this time, the image sensor 202 receives light that has passed through the imaging lens 201 (light that is formed by imaging the plurality of detection patterns 101 with the imaging lens 201) and converts the light into an electrical signal. That is, the plurality of detection patterns 101 are imaged by the camera module 200 (however, an incomplete product in which the relative positional relationship between the imaging lens 201 and the imaging element 202 is not adjusted). The image sensor 202 supplies this electrical signal to the image acquisition unit 103 of the positional deviation adjustment unit 102.

  The image acquisition unit 103 performs well-known predetermined image processing on the electrical signal supplied from the image sensor 202 to generate image data.

  In particular, the image acquisition unit 103 generates image data of images of a plurality of detection patterns 101 captured using the imaging lens 201 and the imaging element 202. The image acquisition unit 103 acquires the image data as a position adjustment image and supplies the image data to the dx calculation unit 104 of the position shift adjustment unit 102.

  The dx calculation unit 104 performs the following processing using the position adjustment image.

  The dx calculation unit 104 approximates the relationship between the image height and contrast of the image of each detection pattern 101 shown in the position adjustment image with a curve, and obtains a value dx based on the curve.

  Here, dx is a position on the spherical surface 101s corresponding to the center of the position adjustment image and a position on the spherical surface 101s corresponding to an arbitrary image height other than the center having the same contrast as the center of the position adjustment image. Is a separation distance in a direction perpendicular to the optical axis 201a. In particular, dx indicates the distance in the direction in which the plurality of detection patterns 101 are arranged. As shown in FIG. 3, when the plurality of detection patterns 101 are arranged in the x direction, dx indicates the distance in the x direction. Show.

  In the present specification, “contrast” is an index indicating the sharpness of an image, and means resolution (resolution). Needless to say, the contrast of the image captured by the camera module changes depending on the object distance to the imaging lens provided in the camera module, the image height in the image, and the like.

  FIG. 4 is a graph for explaining a technique for obtaining dx when the detection pattern 101 (x0) is copied to the center of the position adjustment image among the plurality of detection patterns 101.

  In the example shown in FIG. 4, the contrast of the detection pattern 101 (x0) shown in the center of the position adjustment image is C0.

  The detection pattern 101 (x-2), the detection pattern 101 (x-1), the detection pattern 101 (x1), and the detection pattern 101 (x2) are at positions shifted in the x direction with respect to the detection pattern 101 (x0). Is provided. As a result, the image heights of the detection pattern 101 (x-2), the detection pattern 101 (x-1), the detection pattern 101 (x1), and the detection pattern 101 (x2) that appear in the position adjustment image are the detection pattern 101. Different from (x0).

  Here, as described above, the plurality of detection patterns 101 are arranged such that the object distance to the imaging lens 201 is different for each corresponding image height in the position adjustment image. This means that the detection patterns 101 other than the detection pattern 101 (x0) appear at different image heights in the position adjustment image and the object distances are different from each other.

  Since the image height in the position adjustment image and the object distance to the imaging lens 201 are different among the plurality of detection patterns 101, the distribution of the image height and contrast of each detection pattern 101 in the position adjustment image is different. can get.

  In FIG. 4, a point indicating the relationship between the image height and the contrast regarding the detection pattern 101 (x−2) is denoted as xc−2. In FIG. 4, a point indicating the relationship between the image height and the contrast regarding the detection pattern 101 (x−1) is denoted as xc−1. In FIG. 4, the point indicating the relationship between the image height and the contrast regarding the detection pattern 101 (x0) is denoted as xc0. In FIG. 4, the point indicating the relationship between the image height and the contrast regarding the detection pattern 101 (x1) is denoted by xc1. In FIG. 4, a point indicating the relationship between the image height and the contrast regarding the detection pattern 101 (x2) is denoted by xc2.

  Then, the dx calculation unit 104 refers to the five points xc-2, xc-1, xc0, xc1, and xc2 shown in FIG. 4, and the image height and contrast of the plurality of detection patterns 101 that appear in the position adjustment image. Is approximated by a curve.

  The approximation by the above curve can be easily performed by a known least square method or the like. The approximate curve is not particularly limited as long as it has a function for drawing a continuous curve.

  Then, the dx calculation unit 104 has a contrast C0 other than the center of the position adjustment image from an approximate curve (see FIG. 4) showing the relationship between the image height and the contrast of the plurality of detection patterns 101 shown in the position adjustment image. One point of the obtained image height is specified. Here, the image height at which the contrast C0 is obtained other than the center of the position adjustment image is xa.

  Then, the dx calculation unit 104 calculates the position between the position on the spherical surface 101s corresponding to the center of the position adjustment image (that is, the position where the detection pattern 101 (x0) is present) and the position on the spherical surface 101s corresponding to the image height xa. , The separation distance in the x direction is obtained, and this is defined as dx. Note that dx is an actual separation distance on the object side where an image is formed by the imaging lens 201.

  The dx calculation unit 104 supplies the dx obtained as described above to the tilt amount calculation unit 105 as the number for calculation in the tilt amount calculation unit 105.

  When the distance between the center 101c and the spherical surface 101s, that is, the radius of the sphere is R, the tilt amount calculation unit 105 is represented by the following formula (1).

Thus, an inclination amount θ in the direction of the optical axis 201a of the light receiving surface 204 of the imaging element 202 with respect to the imaging lens 201 is obtained.

  Here, the inclination amount θ indicates the inclination angle of the light receiving surface 204 in the direction of the optical axis 201a when the direction in which the plurality of detection patterns 101 are arranged is the inclination amount θ = 0 ° (no inclination). As shown in FIG. 3, when a plurality of detection patterns 101 are arranged in the x direction, an inclination angle in the direction of the optical axis 201a with respect to the x direction is shown.

  FIG. 5 shows a correlation between the measurement chart 301 with alignment mark shown in FIG. 3, dx, and the inclination amount θ. FIG. 5 is a view of the measurement chart 301 with alignment marks as viewed from above, and the line of sight is the same as FIG.

  That is, in FIG. 5, a point 301a that is a position on the spherical surface 101s corresponding to the image height xa is on the right side (in other words, in other words, a point 301s that is a position on the spherical surface 101s corresponding to the center of the position adjustment image. dx is a positive value when it is on the side of θ = 0 °. On the other hand, in FIG. 5, when the point 301a is on the left side (in other words, θ = 180 ° side) with respect to the point 301s, dx takes a negative value. FIG. 5 conceptually shows such a relationship between dx and the inclination amount θ, where dx is a negative value and dx is a positive value.

  When the information indicating the tilt amount θ is supplied from the tilt amount calculation unit 105, the member displacement unit 106 displaces the imaging lens 201 and / or the image sensor 202 so as to correct the tilt amount θ based on this information. It is something to be made.

  In addition, as illustrated in FIG. 1, the position deviation adjustment unit 102 may include an axis deviation amount calculation unit 107.

  The axis shift amount calculation unit 107 performs the calculation using the position adjustment image separately from the dx calculation unit 104 and the tilt amount calculation unit 105, and the center 204 c of the optical axis 201 a of the imaging lens 201 and the light receiving surface 204 of the imaging element 202. The relative positional deviation is obtained. More specifically, the axis deviation amount calculation unit 107 obtains a relative positional deviation between a straight line extending in a direction perpendicular to the light receiving surface 204 from the center 204c and the optical axis 201a.

  The axis deviation amount calculation unit 107 calculates, for example, the amount of deviation of the at least one detection pattern 101 that appears in the position adjustment image with respect to the ideal arrangement, and the relative relationship between the optical axis 201a and the center 204c corresponding to the calculation result. A typical positional shift amount is obtained. The technique for obtaining the positional deviation in this way can also be realized by a known technique. At this time, the member displacement unit 106 indicates the relative displacement amount between the optical axis 201 a of the imaging lens 201 and the center 204 c of the light receiving surface 204 of the imaging element 202, which is supplied from the axial displacement amount calculation unit 107. Based on the information, the imaging lens 201 and / or the imaging element 202 may be displaced so as to correct the positional deviation amount.

  In this embodiment, an example in which a plurality of detection patterns 101 are arranged in the x direction has been described. However, the arrangement direction of the plurality of detection patterns 101 with respect to the direction perpendicular to the optical axis 201a is: Either direction is acceptable. The value dx and the inclination amount θ change in accordance with the arrangement direction of the plurality of detection patterns 101 with respect to the direction perpendicular to the optical axis 201a in accordance with the relationship shown in FIG.

[Summary]
In order to solve the above problem, a position adjustment device according to an aspect of the present invention is a position adjustment device that adjusts the relative positional relationship between an imaging lens and an imaging element, and includes a plurality of measurement objects (detection). Pattern 101) and the contrast asymmetry with respect to the center of the position adjustment image, which is an image obtained by imaging the plurality of measurement objects using the imaging lens and the imaging element. A positional shift adjustment unit that adjusts a relative positional shift between the imaging lens and the imaging device, and each of the plurality of measurement objects is set at any one of a plurality of image heights in the position adjustment image. It is characterized in that the object distance to the imaging lens is different for each image height corresponding to the image.

  According to the above configuration, the measurement object is arranged so that the object distance to the imaging lens is different for each image height of the position adjustment image. This makes it easy to control the position of the measurement object, imaging lens, imaging device, etc., and obtain the output signal of the imaging device for each focus shift position. It is possible to obtain an image for position adjustment that reflects the relationship (defocus characteristic) of the module resolving power.

  As a result, according to the position adjusting device, since the amount of data handled at the time of adjustment can be reduced as compared with the conventional case, the relative positional relationship between the imaging lens and the imaging element can be adjusted in a short time. .

  In addition, according to the above configuration, the relative positional relationship between the imaging lens and the imaging device can be directly adjusted while performing imaging using only the imaging device mounted on the completed camera module as the imaging device. Therefore, adjustment can be performed with high accuracy.

  In the position adjustment device according to an aspect of the present invention, the plurality of measurement objects are arranged on the same spherical surface, and the center of the sphere constituting the spherical surface extends the optical axis of the imaging lens. It is preferable to lie on a straight line.

  Further, in the position adjustment device according to one aspect of the present invention, the radius of the sphere is R, and the position on the spherical surface corresponding to the center of the position adjustment image has the same contrast as the center of the position adjustment image. If the separation distance in the direction perpendicular to the optical axis of the imaging lens with respect to the position on the spherical surface corresponding to an arbitrary image height other than the center is dx, the positional deviation adjustment unit is represented by the above formula. According to (1), it is preferable that an inclination amount calculation unit for obtaining an inclination amount θ of the light receiving surface of the imaging element with respect to the imaging lens in the optical axis direction of the imaging lens is provided.

  According to the above configuration, the relative positional deviation between the imaging lens and the imaging element can be obtained quantitatively with a simple operation as the tilt amount θ.

  Further, in the position adjustment device according to one aspect of the present invention, the position deviation adjustment unit approximates the relationship between the image height and contrast of each measurement object image shown in the position adjustment image by a curve, It is preferable that a dx calculation unit for obtaining the above dx based on the curve is provided.

  According to said structure, said value dx can be calculated | required easily.

  A position adjustment method according to an aspect of the present invention is a position adjustment method for adjusting a relative positional relationship between an imaging lens and an imaging element, and includes a plurality of measurements using the imaging lens and the imaging element. Based on the contrast asymmetry with respect to the center of the position adjustment image that is an image obtained by imaging the object, the relative positional deviation between the imaging lens and the imaging element is adjusted, Each of the measurement objects is arranged so as to appear in any one of a plurality of image heights in the position adjustment image, and the object distance to the imaging lens is different for each corresponding image height. It is said.

  According to said structure, there exists an effect similar to the position adjustment apparatus which concerns on each aspect of this invention.

  The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

  INDUSTRIAL APPLICABILITY The present invention can be used for a position adjustment device and a position adjustment method that adjust the relative positional relationship between an imaging lens and an imaging element.

101 Detection pattern (object for measurement)
101c Center of sphere 101s Spherical surface 102 Position shift adjustment unit 104 dx calculation unit 105 Inclination amount calculation unit 200 Camera module 201 Imaging lens 201a Optical axis 202 Imaging element 204 Light receiving surface

Claims (3)

A position adjustment device for adjusting a relative positional relationship between an imaging lens and an imaging element,
Multiple measuring objects;
Each of the obtained images of the plurality of measurement objects obtained with reference to the center of the position adjustment image that is an image obtained by imaging the plurality of measurement objects using the imaging lens and the imaging element . A positional deviation adjusting unit that adjusts a relative positional deviation between the imaging lens and the imaging element based on the asymmetry of the relationship between the image height and the contrast;
The plurality of measurement objects are:
Each so as to appear in any of a plurality of image heights in the position adjustment image, and
For each corresponding image height, the object distance to the imaging lens is arranged differently ,
The plurality of measurement objects are arranged on the same spherical surface,
The center of the sphere constituting the spherical surface is located on a straight line obtained by extending the optical axis of the imaging lens,
Let the radius of the sphere be R,
The imaging of the position on the spherical surface corresponding to the center of the image for position adjustment and the position on the spherical surface corresponding to an arbitrary image height other than the center having the same contrast as the center of the image for position adjustment If the separation distance in the direction perpendicular to the optical axis of the lens is dx,
The positional deviation adjusting unit is represented by the following mathematical formula (1).

Thus, the position adjustment device is provided with an inclination amount calculation unit that obtains an inclination amount θ of the light receiving surface of the imaging element with respect to the imaging lens in the optical axis direction of the imaging lens . The positional deviation adjustment unit includes a dx calculation unit that approximates the relationship between the image height and the contrast of each measurement object image in the position adjustment image by a curve and obtains the dx based on the curve. The position adjusting device according to claim 1 , wherein A position adjustment method for adjusting a relative positional relationship between an imaging lens and an imaging element,
Each of the obtained images of the plurality of measurement objects with reference to the center of the position adjustment image that is an image obtained by imaging the plurality of measurement objects using the imaging lens and the imaging element. Based on the asymmetry of the relationship between high and contrast , the relative positional deviation between the imaging lens and the imaging element is adjusted,
The plurality of measurement objects are
Each so as to appear in any of a plurality of image heights in the position adjustment image, and
For each corresponding image height, the object distance to the imaging lens is different ,
The plurality of measurement objects are arranged on the same spherical surface,
The center of the sphere constituting the spherical surface is positioned on a straight line obtained by extending the optical axis of the imaging lens,
Let the radius of the sphere be R,
The imaging of the position on the spherical surface corresponding to the center of the image for position adjustment and the position on the spherical surface corresponding to an arbitrary image height other than the center having the same contrast as the center of the image for position adjustment If the separation distance in the direction perpendicular to the optical axis of the lens is dx,
The following mathematical formula (1)

To obtain an inclination amount θ of the light-receiving surface of the imaging element with respect to the imaging lens in the optical axis direction of the imaging lens .

Images