JP7124569B2 - inspection equipment - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inspection apparatus for inspecting the presence or absence of defects on the surface of an object to be inspected, which has surfaces with different normal vectors.

For example, during the manufacturing process of a product, irregularities that are not designed may be formed on the surface of the product. Such unevenness is a defect in terms of product quality. In addition, the surface of the product may be painted. Otherwise, the coating may become defective. Even in such a case, unevenness that is not assumed in terms of design is formed on the surface of the product, resulting in defects in product quality. Therefore, conventionally, techniques for inspecting the presence or absence of such defects have been used (for example, Patent Documents 1 to 3).

Patent Literature 1 describes a surface defect inspection apparatus for inspecting defects on the surface of a coated object to be inspected. This surface defect inspection apparatus includes an illumination unit that irradiates a striped pattern on the surface of an inspection object, and an imaging unit that captures an image of the inspection object irradiated with the stripe pattern. Inspect the surface of the object for defects. The striped pattern imaged by the imaging unit changes in the period and shape of the striped pattern due to defects (unevenness) on the surface of the inspection object. inspecting. Here, the imaged stripe pattern changes depending on not only surface defects but also the shape of the inspection object. Therefore, when the surface of the object to be inspected consists of surfaces having various curvatures, it is necessary to divide the surface of the object to be inspected into small regions for each curvature and project a suitable fringe pattern for each of the small regions. Yes, inspection is required as many times as the number of divisions. Therefore, in the surface defect inspection apparatus of Patent Document 1, in order to inspect the surface of the inspection object having various curvatures at once, blue, green, and red with different light and dark cycles are combined according to each curved surface. The striped pattern is projected, the striped pattern reflected by the object to be inspected is imaged by the imaging unit, and the captured image is divided into blue, green, and red components, respectively, to obtain an image corresponding to the curvature of the curved surface. An image of a striped pattern with a light-dark cycle is acquired. This makes it possible to inspect the surfaces of inspection objects having various curvatures with a single imaging.

Patent Literature 2 also describes an inspection apparatus for inspecting defects on the surface of an inspection object. In order to inspect the surface of an object to be inspected having various curvatures at once, this inspection apparatus images the surface of the object to be inspected onto which the stripe pattern is irradiated, instead of projecting a parallel stripe pattern. The striped pattern is produced so that the striped pattern in the imaged image obtained by the above is parallel at regular intervals. As a result, even an inspection object having a surface with various curvatures can be inspected in a single inspection because the cycle, shape, etc. of the fringe pattern change only in the defective portion.

Patent Literature 3 discloses a surface inspection apparatus capable of accurately discriminating convex defects on the surface of a healthy portion such as a casting surface that has fine irregularities. This technology is equipped with an installation table that rotates the casting, a camera that is arranged so that the entire inspection surface of the casting can be imaged without blind spots, and a light that is arranged so that the entire inspection surface of the casting can be illuminated. . The inspection accuracy is improved by overlapping the areas photographed by the respective cameras and inspecting the same defect using a plurality of images.

JP 2011-226814 A JP 2017-194380 A JP 2017-138106 A

The techniques described in Patent Literatures 1 and 2 are capable of inspecting the entire surface of an inspection object having various curvatures in one shot. If the radius is small), a blind spot occurs with respect to the photographing device, and it may not be possible to photograph the entire surface. Further, the angle of reflection of the projected fringe pattern from the surface of the object to be inspected becomes smaller, which reduces the intensity of the photographing light. As a result, there is a possibility that patterns cannot be identified in image processing, and defects cannot be detected. Therefore, when the curvature of the surface of the inspection object is large (the radius of curvature is small), it is necessary to photograph the surface of the inspection object a plurality of times while changing the posture of the inspection object and the imaging device. be.

The technique described in Patent Document 3 uses a plurality of cameras and illuminations, but the number of captured images used to inspect for the presence or absence of defects increases, resulting in a longer inspection time.

Therefore, there is a demand for an inspection apparatus capable of quickly inspecting for the presence or absence of defects regardless of the curvature of the surface of the object to be inspected.

A characteristic configuration of an inspection apparatus according to the present invention is an inspection apparatus for inspecting the presence or absence of defects on the surface of an inspection object configured to have surfaces with different normal vectors, and and an irradiating unit for irradiating the inspection object with light by emitting light, and each optical axis is set based on the normal vector, and an imaged image of the inspection object irradiated with the light is acquired at the same time. light emission position coordinate information indicating the coordinates of the light emission positions on the display screen; and light receiving positions of the light in each of the captured images acquired by the plurality of image pickup image acquisition sections. a calculation unit for calculating the coordinates on the display screen corresponding to the coordinates in each of the captured images based on the light receiving position coordinate information indicating the coordinates; and the simultaneously captured images based on the calculation result of the calculation unit. In each of the above, an inspection pattern for inspecting the presence or absence of the defect is displayed on the display screen so that a first pattern having a brightness of a predetermined or more and a second pattern darker than the brightness of the first pattern are alternately arranged. and an inspection pattern creation unit that creates auxiliary inspection patterns in which the colors of the first patterns are different from each other for each of the surfaces having different normal vectors, and superimposes the auxiliary inspection patterns. and to prepare the inspection pattern .

With such a characteristic configuration, since a plurality of captured image acquisition units are arranged according to the shape of the inspection object, the inspection pattern enables inspection of the presence or absence of defects even in areas where mutual captured image acquisition units are blind spots. can be easily produced. Therefore, by using such an inspection pattern, it is possible to realize an inspection apparatus capable of quickly inspecting for the presence or absence of defects regardless of the curvature of the surface of the object to be inspected.

Further, if necessary, the captured image acquisition unit rotates the captured image acquisition unit about the normal vector of the surface to be imaged as a rotation axis, thereby moving the projection position of the inspection pattern sweeping onto the surface. can be done. Even in such a case, since the incident angle of the light emitted from the irradiation unit to the surface to be imaged does not change and the brightness does not change, it is possible to perform inspection appropriately.

Furthermore, the plurality of captured image acquisition units capture images of planes having different normal vectors, and there is no need to acquire a plurality of captured images of the same plane as in the technique described in Patent Document 3. Therefore, an increase in captured image can be suppressed.
Further, with such a configuration, by extracting only the color components related to the auxiliary inspection pattern of the surface to be inspected from the captured image acquired by each of the captured image acquisition units, inspection for the presence or absence of defects can be performed appropriately. It is possible to do

a composite image generating unit for extracting an inspection target area to be inspected for the presence or absence of the defect from the captured images acquired by each of the plurality of captured image acquisition units and generating one combined image; It is preferable to inspect the presence or absence of defects on the surface of the inspection object based on the synthesized image.

With such a configuration, the inspection object area necessary for inspection is extracted and inspected, so that the computational load related to inspection can be reduced. In addition, since a plurality of inspection target areas are combined into one image for inspection, even if the number of surfaces to be inspected increases, it takes the same amount of time as in the conventional case (when there is only one captured image acquisition unit). can be inspected.

In addition, the inspection pattern generation unit may generate, as the inspection patterns, a first inspection pattern in which the first pattern and the second pattern are arranged along a predetermined direction in the captured image, and the first inspection pattern in the captured image. It is preferable to fabricate a second inspection pattern in which the pattern and the second pattern are arranged along a direction crossing the predetermined direction.

With such a configuration, when a defect exists along a direction orthogonal to the direction in which the first pattern and the second pattern are arranged in the captured image (extending direction of the first pattern and the second pattern in the captured image), Even so, the inspection can be performed using the second inspection pattern including the first pattern and the second pattern arranged in the direction intersecting the defect in the captured image, so that the defect can be prevented from being overlooked.

It is a schematic diagram which shows the structure of an inspection apparatus. It is a figure which shows the arrangement|positioning relationship of the to-be-inspected object and the captured image acquisition part which concern on 1st Embodiment. FIG. 4 is a diagram showing the concept of calculating coordinates; FIG. 4 is a diagram showing the concept of creating an inspection pattern; It is a figure which shows an example of an inspection pattern. FIG. 10 is a diagram showing preparation of an inspection pattern according to the second embodiment; FIG. 10 is a diagram showing preparation of an inspection pattern according to the second embodiment; FIG. 11 is a diagram showing a synthesized image according to the second embodiment; FIG. FIG. 10 is a diagram showing the preparation of inspection patterns according to the third embodiment; FIG. 12 is a diagram showing the preparation of inspection patterns according to the fourth embodiment; FIG. 10 is a diagram showing an inspection pattern according to another embodiment;

1. First Embodiment An inspection apparatus according to the present invention is configured so as to be able to quickly inspect the presence or absence of defects on the surface of an object to be inspected. The inspection apparatus 1 of this embodiment will be described below.

FIG. 1 is a diagram schematically showing the configuration of an inspection apparatus 1 of this embodiment. As shown in FIG. 1, the inspection apparatus 1 includes an irradiation section 10, a captured image acquisition section 20, a calculation section 30, and an inspection pattern preparation section 40. As shown in FIG.

The irradiation unit 10 irradiates the inspection object 2 with light by causing a predetermined position in the display screen 11 to emit light. The irradiation unit 10 irradiates the inspection object 2 with light when inspecting the presence or absence of defects on the surface of the inspection object 2 and when creating an inspection pattern for such inspection. The irradiation unit 10 includes a display unit such as a liquid crystal display or an organic EL display. do.

Here, the inspection apparatus 1 of the present embodiment inspects the presence or absence of defects on the surface of the inspection object 2 configured to have surfaces with different normal vectors. A side view of the test object 2 is shown in FIG. A normal vector is a unit vector in a direction perpendicular to a given plane. In the example of FIG. 2, an inspection object 2 having a curved surface with different heights in the Z direction along the Y direction is shown, and v1, v2, and v3 are shown as normal vectors. Therefore, in the example of FIG. 2, the surfaces having different normal vectors correspond to the surface s1 having the normal vector v1, the surface s2 having the normal vector v2, and the surface s3 having the normal vector v3. Note that the inspection object 2 may be a combination of a plurality of flat surfaces as well as such a curved surface. The irradiation unit 10 irradiates light over a wide range of the surface of the inspection object 2 including the surfaces s1 to s3.

A plurality of captured image acquisition units 20 are provided. In this embodiment, three captured image acquisition units 20 are provided so that the surface of the inspection object 2 can be captured over a wide range. In the following description, the three captured image acquisition units 20 will be referred to as a captured image acquisition unit 22, a captured image acquisition unit 23, and a captured image acquisition unit 24 when described separately.

The respective optical axes of the plurality of captured image acquisition units 20 are set based on the display screen 11 of the irradiation unit 10 and the normal vector v1-v3 described above. The captured image acquiring unit 22 is arranged so that the surface s1 irradiated with light from the display screen 11 of the irradiating unit 10 and its surrounding surfaces can be imaged in order to inspect the presence or absence of defects on the surface s1 and its surrounding surfaces. be done. Therefore, the captured image acquisition unit 22 determines the angle θ1 between the incident direction of the light irradiated from the display screen 11 to the surface s1 and the normal vector v1, and the angle θ1 between the optical axis of the captured image acquisition unit 22 and the normal vector v1. are arranged so that the angle .theta.2 formed therebetween is equal. Similarly, the captured image acquisition unit 23 determines the angle θ3 between the incident direction of the light emitted from the display screen 11 to the surface s2 and the normal vector v2, the optical axis of the captured image acquisition unit 23, and the normal vector v2. are arranged so as to be equal to the angle θ4 formed by In addition, the captured image acquisition unit 24 determines the angle θ5 between the incident direction of the light emitted from the display screen 11 to the surface s3 and the normal vector v3, and the angle θ5 between the optical axis of the captured image acquisition unit 24 and the normal vector v3. It is arranged so that the angle .theta.6 formed therebetween becomes equal. By using a plurality of captured image acquisition units 20 having respective optical axes set in this manner, it is possible to capture an image of the entire surface (wide range) of the inspection object 2 as shown in FIG. .

The captured image acquisition unit 20 acquires a captured image 21 (described later) obtained by capturing the inspection object 2 irradiated with light at the same time. Here, if the surface of the inspection object 2 to be inspected by the inspection apparatus 1 is smooth or coated, etc., when the irradiation unit 10 irradiates light, the inspection object 2 light is reflected on the surface of The captured image acquisition unit 20 acquires a captured image 21 of the inspection object 2 in such a light-reflecting state. The captured image acquisition unit 20 can be configured using an imaging device such as a CMOS image sensor, a CCD image sensor, or the like. In this embodiment, each of the captured image acquisition unit 22, the captured image acquisition unit 23, and the captured image acquisition unit 24 acquires the captured image 21 at the same time.

Returning to FIG. 1, the calculation unit 30 calculates light emission position coordinate information indicating the coordinates of the light emission position on the display screen 11 and the coordinates of the light reception position in each of the captured images 21 acquired by the plurality of captured image acquisition units 20. , and the coordinates on the display screen 11 corresponding to the coordinates on each of the captured images 21 are calculated. Here, as shown in FIG. 3A, the display screen 11 is divided into predetermined sizes, and the divided areas are defined by coordinates. This division may be performed in units of pixels of the display screen 11, or may be performed by using one aggregate made up of a plurality of pixels as a unit area.

Here, when the inspection apparatus 1 prepares an inspection pattern, the irradiation unit 10 emits light while sequentially moving the light emission position for each region, and each of the plurality of captured image acquisition units 20 emits light each time the light emission position moves. , the captured image 21 is acquired. Information indicating the coordinates defining the light emission position at this time corresponds to the light emission position coordinate information. Therefore, the light emission position coordinate information is transmitted from the irradiation unit 10 to the calculation unit 30 .

On the other hand, the information indicating the coordinates defining the light receiving position in the captured image 21 acquired by each of the captured image acquisition units 22 to 24 corresponds to the light receiving position coordinate information. The coordinates defining the light receiving position may be calculated by each of the captured image acquisition units 22 to 24, or may be calculated by the calculation unit 30 using the captured image 21 acquired by each of the captured image acquisition units 22 to 24. You can calculate. Therefore, when the coordinates defining the light receiving position are calculated by each of the captured image acquiring units 22 to 24, the light emitting position coordinate information is transmitted from the irradiation unit 10 to the calculating unit 30, and the light receiving position is calculated. When the coordinates to be specified are calculated by the calculation section 30, the captured image 21 is transmitted from each of the captured image acquisition sections 22 to 24 to the calculation section 30. FIG.

Here, as described above, the display screen 11 is divided into a plurality of areas with a predetermined size. In the present embodiment, each of the captured images 21 acquired by each captured image acquiring unit 20 also has a plurality of predetermined sizes, as shown in FIGS. area. In the example of FIG. 3, the display screen 11 is divided into x in the horizontal direction and y in the vertical direction. As shown in FIG. It is divided vertically into Y1. Further, as shown in (C) of FIG. 3, the captured image 21 acquired by the captured image acquisition unit 23 is divided into X2 in the horizontal direction and Y2 in the vertical direction, and as shown in (D) of FIG. The captured image 21 acquired by the captured image acquiring unit 24 is divided into X3 in the horizontal direction and Y3 in the vertical direction.

For this reason, the above-mentioned "to calculate the coordinates on the display screen 11 corresponding to the coordinates on each of the captured images 21" means that each area divided by a predetermined size on the display screen 11 is 24, to determine which of a plurality of regions divided by a predetermined size corresponds to the imaged image 21 acquired by each of 24. FIG. Such calculation can be performed by causing the irradiation unit 10 to emit light for each region on the display screen 11, and specifying the coordinates of the region where light is received in each captured image 21 acquired at this time. be. Note that X and x1, x2, and x3 may be in the same unit (pixel, mm, etc.), or may be in different units. Also, Y and y1, y2, and y3 may be in the same unit, or may be in different units.

Based on the calculation result of the calculation unit 30, the inspection pattern generation unit 40 generates a first pattern F having a brightness equal to or higher than a predetermined brightness and a second pattern S darker than the first pattern F in each of the captured images 21 captured at the same time. are displayed alternately on the display screen 11, and an inspection pattern for inspecting the presence or absence of defects on the surface of the inspection object 2 is produced.

The calculation result of the calculation unit 30 is the result of calculating the coordinates on the display screen 11 corresponding to the coordinates in the captured image 21 acquired by each of the captured image acquisition units 22 to 24. is transmitted to The “first pattern F having brightness equal to or higher than a predetermined brightness” is a display object displayed with brightness equal to or higher than a predetermined brightness in the captured image 21, and corresponds to, for example, a white display object. On the other hand, the “second pattern S darker than the first pattern F” is a display object displayed in the captured image 21 with a brightness darker than the first pattern F, for example, a black display object. corresponds to In the following, for ease of understanding, a pattern including both the first pattern F and the second pattern S in the captured image 21 will be described as a bright and dark pattern.

Here, as shown in FIG. 4A, a pattern in which a white strip pattern and a black strip pattern are arranged in parallel with the same width on the display screen 11 is used as the inspection pattern. However, depending on the shape of the surface of the inspection object 2, the pattern included in the captured image 21 may not always be the same as the inspection pattern. Specifically, for example, even if the surface of the object to be inspected 2 is a flat surface, if the surface of the inspection object 2 has an angle with respect to the flat surface as it approaches the side surface, as shown in FIG. The light-dark pattern included in the image 21 appears as if both sides are curved.

Further, when there is a defect on the surface of the inspection object 2 to be inspected by the inspection apparatus 1, even when the irradiation unit 10 irradiates the inspection object 2 with a parallel pattern of light and dark, as is well known, imaging is performed. The light and dark patterns contained in image 21 are non-parallel depending on the defect. Therefore, as shown in FIG. 4B, when the pattern included in the captured image 21 is curved on both sides, the presence or absence of defects on the surface of the inspection object 2 can be easily inspected. Gone.

Therefore, in the present inspection apparatus 1, the inspection pattern is arranged such that the light and dark patterns included in the captured images 21 acquired by the captured image acquisition units 22 to 24 are parallel as shown in FIG. 4C. is produced. In particular, in the present embodiment, the inspection pattern generation unit 40 generates inspection patterns so that the widths of the first pattern F and the second pattern S in the captured image 21 acquired by each of the captured image acquisition units 22 to 24 are constant. to make. By preparing the inspection pattern in this way, when there is a defect on the surface of the inspection object 2, the distortion of the light-and-dark pattern corresponding to the defect in the captured image 21 can be made more conspicuous. Therefore, it becomes possible to make it easy to appropriately inspect (determine) the presence or absence of defects. In the captured image 21, the inspection pattern formed by alternately arranging the first patterns F and the second patterns S conforms to the shape of the surface of the inspection object 2 as shown in FIG. It may be arcuate or have edges (not shown) accordingly.

An example of an inspection pattern formed in this manner is shown in FIG. The inspection pattern shown in FIG. 5 is produced according to the captured image acquisition unit 20, the display screen 11, and the inspection target surface of the inspection object 2 as shown in FIG. Therefore, it is possible to inspect the presence or absence of defects over a wide range of the surfaces of the inspection object 2 . Note that even when such an inspection pattern is used, when inspecting an area of the inspection object 2 that cannot be inspected, the inspection apparatus 1 causes the attitude change control unit 3 to change the attitude of the inspection object 2 to support it. It is preferable that the unit 4 is controlled to move to a position where a predetermined inspection pattern is easily irradiated, and the inspection is performed by irradiating the inspection pattern.

Here, when the inspection pattern creating unit 40 creates an inspection pattern, the irradiation unit 10 may be configured to irradiate the inspection object 2 with dot-shaped light. This makes it possible to accurately calculate the coordinates on the display screen 11 corresponding to the coordinates on each captured image 21 . Therefore, since the inspection pattern can be appropriately produced along the surface of the inspection object 2, it is possible to accurately inspect the presence or absence of defects.

Further, for example, the irradiation unit 10 can be configured to irradiate the inspection object 2 with linear light. In this case, since the light can be irradiated over a wider range than when the light is irradiated in dots, the coordinates on the display screen 11 corresponding to the coordinates on the captured image 21 can be calculated quickly. It becomes possible. Therefore, it is possible to rapidly fabricate an inspection pattern.

Alternatively, the irradiating unit 10 is configured to irradiate the dot-shaped light only to the portion where the inspection pattern generating unit 40 cannot generate the inspection pattern as a result of irradiating the inspection object 2 with the linear light. You can By adopting such a configuration, while the inspection pattern can be produced quickly by irradiating the linear light, the portion where the inspection pattern cannot be produced by irradiating the linear light can be supplemented by irradiating the dot-shaped light. It becomes possible to fabricate an inspection pattern by using the

The inspection apparatus 1 inspects the presence or absence of defects on the surface of the inspection object 2 based on the inspection pattern thus produced. Since a known technique can be used to inspect the presence or absence of defects on the surface, an example thereof will be briefly described below.

First, the posture change control unit 3 sets the inspection object 2 to a posture corresponding to the inspection. Next, the irradiation unit 10 displays an inspection pattern corresponding to this posture on the display screen 11 and irradiates the inspection object 2 with light. captures the irradiated surface of the inspection object 2 . Image processing is performed on each of the acquired captured images 21 to detect the boundary portion between the first pattern F and the second pattern S, and a fringe edge image is generated by drawing the boundary portion.

Next, the irradiation unit 10 slides the inspection pattern by a preset amount along the direction in which the first pattern F and the second pattern S are arranged, and generates a stripe edge image in the same manner as described above. This fringe edge image is generated until the amount of sliding movement of the inspection pattern reaches a preset amount (for example, one period), and a fringe edge image is similarly generated. At this time, every time a striped edge image is generated, each striped edge image is superimposed and synthesized.

When the movement amount of the slide movement reaches a preset amount, it is determined whether or not there is a portion having a luminance equal to or lower than a preset first threshold in the superimposed image. It is determined whether or not there is a portion having a large luminance equal to or higher than a second preset threshold. When the superimposed image has a portion having a luminance equal to or lower than a preset first threshold, or has a portion having a luminance equal to or higher than a preset second threshold, the inspection apparatus 1 , it is determined that the surface of the inspection object 2 has a defect.

If it is determined that there is no defect, and if another portion of the inspection object 2 is to be inspected for defects, the inspection is continued. On the other hand, if it is determined that there is a defect, the inspection for the presence or absence of defects on the inspection object 2 ends. As described above, according to the inspection apparatus 1, it is possible to inspect the presence or absence of defects on the surface of the inspection object 2 over a wide range at once.

2. 2nd Embodiment Next, 2nd Embodiment of the inspection apparatus 1 is described. In the first embodiment, FIG. 5 shows an example of the inspection pattern. Depending on the layout relationship of the irradiation unit 10, the captured image acquisition unit 20, and the inspection object 2, and the shape of the inspection object 2, as shown in FIG. and the inspection pattern p5 used for inspecting the surface s5 may overlap. In this case, even if each of the two captured image acquisition units 20 captures images of the surface s4 and the surface s5, the captured image 21 in which the first pattern F and the second pattern S are alternately arranged is not obtained, and the defect is appropriately detected. cannot be inspected for the presence of

Therefore, in the inspection apparatus 1 according to the present embodiment, when the inspection patterns used for inspecting the presence/absence of defects on surfaces having different normal vectors overlap with each other, the inspection pattern creation unit 40 is arranged in the captured image acquisition unit 20 is moved to a position rotated about the normal vector as an axis of rotation, and an inspection pattern is produced.

FIG. 7 shows an example in which the captured image acquisition unit 20 that captures an image of the surface s4 is rotated around the normal vector v4 of the surface s4. By changing the position of the captured image acquisition unit 20 that captures the surface s4 in this way, it is possible to prevent the inspection pattern p4 and the inspection pattern p5 from overlapping on the display screen 11. FIG. Therefore, the captured images 21 acquired by the respective captured image acquisition units 20 are in a state in which the first pattern F and the second pattern S are alternately arranged, and the inspection apparatus 1 determines whether there is a defect on each of the surfaces s4 and s5. can be inspected at the same time.

Here, when inspecting the presence or absence of defects in the inspection object 2, the number of captured image acquisition units 20 used may increase (five captured image acquisition units 20 are shown in the example of FIG. 8). In such a case, it is assumed that it takes time to individually generate the stripe edge image and evaluate the luminance based on the stripe edge image.

Therefore, the inspection apparatus 1 includes a composite image generation unit that extracts an inspection target area to be inspected for defects from the captured images 21 acquired by each of the plurality of captured image acquisition units 20 and generates one combined image. In preparation, it is preferable to inspect the presence or absence of defects on the surface of the inspection object 2 based on this synthesized image. In FIG. 8, the captured images 21 captured by the five captured image acquisition units 20 are shown in (A) to (E). The composite image generation unit extracts an inspection target region including the first pattern F and the second pattern S from each of the captured images 21, synthesizes the inspection target regions extracted from the respective images, and produces (F ) to generate a composite image as shown in FIG. By generating and evaluating a striped edge image as described above using such a composite image, it is possible to quickly inspect for the presence or absence of defects and reduce the computational load associated with the inspection. .

3. 3rd Embodiment Next, 3rd Embodiment of the inspection apparatus 1 is described. In the second embodiment described above, when the inspection patterns used for inspecting the presence/absence of defects on surfaces having different normal vectors overlap with each other, the inspection pattern generation unit 40 causes the captured image acquisition unit 20 to generate normal vectors. Although it has been described that the inspection pattern is produced in a state in which the vector is rotated about the rotation axis, the inspection patterns used for inspecting the presence or absence of defects on surfaces having different normal vectors are mutually different. Configurations with different colors are also possible.

In the present embodiment, the inspection pattern creation unit 40 creates auxiliary inspection patterns in which the colors of the first patterns F are different for respective surfaces having different normal vectors, and creates inspection patterns by superimposing the auxiliary inspection patterns. do. "Each of the surfaces having different normal vectors" refers to the surface s4 having the normal vector v4 and the surface s5 having the normal vector v5 in the example of FIG. "The colors of the first patterns F are different from each other" refers to the first pattern of the captured image 21 captured using an inspection pattern for inspecting the presence or absence of defects on the surface s4 (hereinafter, "auxiliary inspection pattern for the surface s4"). F and the first pattern F of the imaged image 21 captured using the inspection pattern for inspecting the presence or absence of defects on the surface s5 (hereinafter referred to as the "auxiliary inspection pattern for the surface s5"). For example, the auxiliary inspection pattern for the surface s4 may be produced using red and black, and the auxiliary inspection pattern for the surface s5 may be produced using blue and black. Of course, it is possible to use colors other than red and blue, and the second pattern S may also be produced using different colors. Thereby, the colors of the first patterns F of the respective captured images 21 can be made different from each other.

FIG. 9A shows an auxiliary inspection pattern for the surface s4 produced by the inspection pattern production unit 40, and FIG. Such an auxiliary inspection pattern is shown. The inspection pattern production unit 40 superimposes the auxiliary inspection patterns without changing them to produce one inspection pattern as shown in FIG. 9C. In this case, the portion where the first pattern F of the auxiliary inspection pattern for the surface s4 and the first pattern F of the auxiliary inspection pattern for the surface s5 overlap is colored in a composite color (in the case of FIG. 9, red and blue are combined to make purple). ).

When such an inspection pattern is used, the captured image acquisition unit 20 is preferably configured using a color camera capable of identifying the color used as the first pattern F. Specifically, the captured image acquisition unit 20 that captures the surface s4 should be configured to capture only the red component, and the captured image acquisition unit 20 that captures the surface s5 should be configured to capture only the blue component. With this configuration, when the planes s4 and s5 are imaged as shown in FIG. It is possible to do it properly.

4. 4th Embodiment Next, 4th Embodiment of the inspection apparatus 1 is described. In the above-described third embodiment, the inspection pattern creation unit 40 creates auxiliary inspection patterns in which the colors of the first patterns F are different for each of the surfaces having different normal vectors, and does not change the auxiliary inspection patterns. Although it is explained that the inspection patterns are produced by superimposing them, it is also possible to change the inspection patterns used for inspecting the presence or absence of defects on surfaces with different normal vectors, synthesize them into one inspection pattern, and produce it.

In this embodiment, the inspection pattern creation unit 40 creates individual inspection patterns in which the first pattern F and the second pattern S are arranged in parallel in the captured image 21 for each of the surfaces having different normal vectors, and a plurality of captured images are captured. An inspection pattern is produced by synthesizing the individual inspection patterns so that the first pattern F and the second pattern S are alternately arranged at equal intervals in each image 21 .

FIG. 10A shows the individual auxiliary inspection pattern for the surface s4 produced by the inspection pattern production unit 40, and FIG. 10B shows the surface s5 produced by the inspection pattern production unit 40. (for ease of understanding, they are similar to FIGS. 9A and 9B, respectively). (C) of FIG. 10 shows the individual inspection patterns superimposed without change (corresponding to (C) of FIG. 9). In the present embodiment, the inspection pattern generation unit 40 obtains the first pattern F and the second pattern F in the captured image 21 captured by the captured image acquisition unit 20 for the portion where the first patterns overlap in FIG. 10C. An inspection pattern is produced by synthesizing the individual inspection patterns so that the pattern S is alternately arranged at equal intervals (deformed so that the pitch of the stripes becomes equal). FIG. 10D shows an example of an inspection pattern created by synthesis.

A captured image 21 captured using such an inspection pattern is shown in (E) of FIG. In addition, as shown in FIG. 10E, in the captured image 21 of the present embodiment, the first pattern F and the second pattern S are not parallel to each other, but the stripe pitch is evenly spaced. It is possible to appropriately inspect the presence or absence of

5. Other Embodiments In the above embodiment, an example in which the inspection pattern creating unit 40 creates an inspection pattern in which the first pattern F and the second pattern S are arranged in the horizontal direction in the captured image 21 will be described. However, the inspection pattern creating unit 40 can also be configured to create an inspection pattern in which the first pattern F and the second pattern S in the captured image 21 are arranged along the vertical direction.

Here, in the case of using an inspection pattern in which the first pattern F and the second pattern S in the captured image 21 are arranged along the horizontal direction, the defect in the inspection object 2 is detected by the first pattern F and the second pattern S in the captured image 21 . When the direction in which the two patterns S are arranged is perpendicular to the direction in which the first pattern F and the second pattern S are arranged (parallel to the longitudinal direction of the first pattern F and the second pattern S), the change in luminance caused by the defect in the fringe edge image is small. There is a possibility that the existence will be overlooked (see (A) in FIG. 11).

Therefore, the inspection pattern generation unit 40 creates a first inspection pattern in which the first pattern F and the second pattern S are arranged along a predetermined direction in the captured image 21 and the first pattern F in the captured image 21 as inspection patterns. and the second pattern S arranged along a direction crossing a predetermined direction. The first inspection pattern is an inspection pattern in which the first pattern F and the second pattern S in the captured image 21 are arranged along the vertical direction, as shown in FIG. 11A. Therefore, the second pattern S is an inspection pattern in which the first pattern F and the second pattern S in the captured image 21 are arranged along the direction intersecting the vertical direction. FIG. 11B shows an example in which the first pattern F and the second pattern S are arranged in the horizontal direction in the captured image 21 . By using such a first inspection pattern and a second inspection pattern, it is possible to appropriately detect even a defect extending in a predetermined direction in the inspection object 2 .

INDUSTRIAL APPLICABILITY The present invention can be used in an inspection apparatus that inspects the presence or absence of defects on the surface of an inspection object that has surfaces with different normal vectors.

1: Inspection device 2: Inspection object 11: Display screen 10: Irradiation unit 20: Captured image acquisition unit 21: Captured image 30: Calculation unit 40: Inspection pattern preparation unit F: First pattern S: Second pattern s1-s5 : surface v1-v5: normal vector

Claims (4)

An inspection apparatus for inspecting the presence or absence of defects on the surface of an inspection object configured to have surfaces with different normal vectors,
an irradiation unit that emits light at a predetermined position within a display screen to irradiate the inspection object with light;
a plurality of captured image acquisition units configured to acquire captured images of the inspection object to which the respective optical axes are set based on the normal vector and which are irradiated with the light at the same time;
light emitting position coordinate information indicating the coordinates of the light emitting position on the display screen; and light receiving position coordinate information indicating the coordinates of the light receiving position in each of the captured images acquired by the plurality of captured image acquisition units; a calculation unit that calculates coordinates on the display screen corresponding to the coordinates on each of the captured images, based on
Based on the calculation result of the calculation unit, the display is performed such that a first pattern having brightness equal to or higher than a predetermined brightness and a second pattern darker than the brightness of the first pattern are alternately arranged in each of the simultaneously captured images. an inspection pattern creation unit that creates an inspection pattern that is displayed on a screen and inspects for the presence or absence of the defect;
with
The inspection pattern creation unit creates auxiliary inspection patterns in which the colors of the first pattern are different for each of the surfaces having different normal vectors, and superimposes the auxiliary inspection patterns to create the inspection pattern. Device. 2. The inspection apparatus according to claim 1, wherein each of said plurality of captured image acquisition units simultaneously acquires said captured images obtained by capturing only a single color component among mutually different colors used as said first pattern. further comprising a composite image generation unit that extracts an inspection target area to be inspected for the presence or absence of the defect from the captured images acquired by each of the plurality of captured image acquisition units and generates one combined image,
3. The inspection apparatus according to claim 1, wherein the presence or absence of defects on the surface of the inspection object is inspected based on the synthesized image. The inspection pattern generating unit may generate, as the inspection patterns, a first inspection pattern in which the first pattern and the second pattern are arranged along a predetermined direction in the captured image, and the first pattern in the captured image. 4. The inspection apparatus according to any one of claims 1 to 3 , wherein the second pattern and the second pattern are arranged along a direction crossing the predetermined direction.

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