Information processing apparatus, appearance inspection apparatus, information processing method, and program

Abstract

To appropriately illuminate an object to be inspected at the time of imaging.SOLUTION: In a case where the image clarity, which is a feature of the surface of the inspection target object, is low in the color change inspection or the surface unevenness change inspection, the light source to be turned on is a light source having the shortest distance from the optical axis of the imaging device and the largest elevation angle from the inspection target object among the light sources included in the illumination device. In consideration of the spread of the specular reflection light on the surface with low image clarity, the number of light sources that are not turned on is larger than the number of light sources that are not turned on when the image clarity is high. In the gloss change inspection, in a case where the image clarity, which is a feature of the surface of the inspection target object, is low, the light source to be turned on is a light source having an elevation angle equal to or greater than a predetermined angle including a light source closest to the optical axis of the imaging device and having the largest elevation angle from the inspection target object among the light sources included in the illumination device. In consideration of the spread of the specular reflection light on the surface with low image clarity, the number of light sources to be turned on is larger than the number of light sources to be turned on when the image clarity is high.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an information processing technique for controlling a visual inspection apparatus. [Background technology]

[0002] Conventionally, visual inspection devices capture images of an object using an illumination device with multiple light sources arranged in a circular ring, and then inspect the object for defects based on the captured images. The visual inspection device analyzes changes in brightness and chromaticity of the object's surface extracted from the captured images and calculates various evaluation features used to evaluate the presence or absence of defects. The evaluation features include gloss changes based on specular reflection components on the object's surface, color changes based on diffuse reflection components, and surface roughness changes based on diffuse reflection components on multiple object surfaces. Patent Document 1 discloses a technology in which lighting patterns for multiple light sources with different light intensities and directions for illuminating the object are preset, and the lighting patterns are switched appropriately depending on the desired evaluation features. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-105870 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology described in Patent Document 1, the set lighting pattern is based on the assumption that the surface of the object being inspected is in an ideal state, and if the surface of the object being inspected is not ideal, the set lighting pattern may not be able to properly illuminate the object being inspected.

[0005] Therefore, an object of the present disclosure is to provide appropriate illumination when capturing an image of an object to be inspected. [Means for solving the problem]

[0006] The technology disclosed herein comprises a control means for controlling an imaging means for imaging an object to be inspected and an illumination means having a plurality of light sources at different elevation angles from the object to be inspected, and an acquisition means for acquiring characteristic information of the surface of the object to be inspected, wherein the control means sets lighting conditions for the illumination means based on the characteristic information and inspection items for the object to be inspected, turns on the plurality of light sources of the illumination means in accordance with the set lighting conditions, and causes the imaging means to image the object to be inspected in synchronization with the lighting. [Effects of the Invention]

[0007] According to the present invention, it is possible to appropriately illuminate an object to be inspected when imaging the object. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram showing an example of the hardware configuration of an information processing device for controlling an illumination device and an imaging device included in the appearance inspection apparatus according to an embodiment. [Figure 2] FIG. 1 is a diagram showing the configuration of an illumination device according to an embodiment. [Figure 3] FIG. 10 is a diagram showing an illumination lighting pattern according to an embodiment. [Figure 4] FIG. 10 is a diagram showing example setting parameters for a lighting pattern according to an embodiment. [Figure 5] FIG. 2 is a functional block diagram of an information processing device provided in the appearance inspection apparatus according to the first embodiment. [Figure 6] 4 is a flowchart for explaining a visual inspection process according to the first embodiment. [Figure 7] FIG. 10 is a diagram showing an illumination lighting pattern according to the second embodiment. [Figure 8] FIG. 10 is a functional block diagram of an information processing device provided in the appearance inspection apparatus according to the second embodiment. [Figure 9] 10 is a flowchart for explaining a visual inspection process according to the second embodiment. [Figure 10] 10 is a flowchart for explaining a visual inspection process according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the following embodiments do not limit the present invention, and not all of the combinations of features described in the present embodiments are necessarily essential to the solution of the present invention. Note that the same components will be described with the same reference numerals. Furthermore, each process (step) in the flowchart will be indicated with a reference numeral beginning with S.

[0010] [Embodiment 1] 1 shows an example of the hardware configuration of an information processing device for controlling an illumination device and an imaging device included in the appearance inspection apparatus according to this embodiment. The information processing device 100 includes a CPU 101, a ROM 102, a RAM 103, a VC (video card) 104, a general-purpose I / F (interface) 105, a SATA (serial ATA) I / F 106, and a NIC (network interface card) 107. The CPU 101 uses the RAM 103 as a work memory to execute an OS (operating system) and various programs stored in the ROM 102, a HDD (hard disk drive) 113, etc. The CPU 101 also controls each component via a system bus 108. Note that, in the processing according to the flowcharts described below, program codes stored in the ROM 102, the HDD 113, etc. are loaded into the RAM 103 and executed by the CPU 101. A display 115 is connected to the VC 104. To the general-purpose I / F 105, input devices such as a mouse 110 and a keyboard 111, as well as an illumination device 116 and an imaging device 117 of an external device, are connected via a serial bus 109. To the SATA I / F 106, a general-purpose drive 114 that reads and writes from and to an HDD 113 and various storage media is connected via a serial bus 112. The NIC 107 inputs and outputs information to and from external devices. The CPU 101 uses the various storage media mounted on the HDD 113 and the general-purpose drive 114 as storage locations for various data. The CPU 101 displays a UI (graphical user interface) provided by a program on a display 115, and accepts inputs such as user instructions via the mouse 110 and the keyboard 111.

[0011] The information processing device 100 stores surface feature information relating to the surface features of the object under test in advance in either the RAM 103 or the HDD 113, and acquires this surface feature information by referencing the storage location. This surface feature information includes information on at least the image clarity of the object under test and the surface texture of the object under test, and may be editable by the user. The information on image clarity is information on the glossiness of the object under test, the amount of gloss change on the object under test, and the ratio of specular reflection light components to diffuse reflection light components of the light reflected from the object under test. The information on surface texture is information on the complexity of the irregularities on the object under test's surface, i.e., surface roughness.

[0012] 2 shows an example of the configuration of the illumination device 116 and the imaging device 117 in the appearance inspection apparatus of this embodiment. Fig. 2(a) is a diagram showing the illumination device 116 as seen from the side, and Fig. 2(b) is a diagram showing the illumination device 116 as seen from directly above.

[0013] The illumination device 116 has a plurality of light sources 201 arranged radially around the zenith of a hemisphere, and the diametrical surface of the hemisphere serves as the installation surface for the inspection object 202. By placing the inspection object 202 at the center of the diametrical surface, the illumination device 116 is able to illuminate the inspection object 202 all around with light sources at a plurality of different elevation angles. The elevation angle in this disclosure refers to the angle from the inspection object 202 placed at the center of the diametrical surface of the illumination device 116. In addition, an imaging device 117 can be installed at the zenith of the hemisphere of the illumination device 116 so as to directly face the inspection object 202 placed at the center of the diametrical surface. The imaging device 117 can capture an image of the surface of the inspection object in synchronization with the lighting of each light source 201.

[0014] In the present embodiment, the lighting device 116 is configured so that the on / off of each light source 201 can be controlled individually, but the present invention is not limited to this. For example, the lighting device 116 may be configured so that the on / off of each of a plurality of adjacent light sources 201 can be controlled individually in order to obtain sufficient light intensity.

[0015] Here, examples of inspection items in this embodiment will be described. The inspection items include inspection for gloss change, inspection for color change, and inspection for surface unevenness change.

[0016] In the gloss change inspection, the specular reflection component of light from the light source on the surface of the object being inspected is acquired as an evaluation feature, and the presence or absence of a gloss change is determined based on whether the change in brightness distribution or distribution range of the specular reflection component is greater than or equal to a predetermined threshold.

[0017] In color change inspection, the diffuse reflection light component, which does not include the specular reflection light component of light from the light source on the surface of the object being inspected, is acquired as an evaluation feature, and the presence or absence of a color change is determined based on whether the change in the chromaticity distribution or distribution range of the diffuse reflection light component is greater than or equal to a predetermined threshold.

[0018] Surface unevenness change inspection is aimed at detecting uneven defects in areas of the surface of an object that should be smooth. In surface unevenness change inspection, the surface of the object is sequentially illuminated from multiple directions and captured, and from the images obtained, surface unevenness, changes in surface unevenness, area and size of the unevenness changes, etc. are calculated as evaluation feature quantities using normal vector estimation processing, typically photometric stereo. The presence or absence of uneven defects on the surface of the object is determined by determining whether the calculated evaluation feature quantities are above a predetermined threshold.

[0019] Next, the influence of the surface characteristics of the inspection object on each inspection item will be described.

[0020] The gloss change inspection acquires and evaluates the specular reflection component of light from the light source on the surface of the object being inspected, while the color change inspection and surface unevenness change inspection acquire and evaluate the diffuse reflection component, avoiding the specular reflection component of the light from the light source on the surface of the object being inspected.

[0021] Therefore, one of the characteristics of the surface of an object being inspected that affects each inspection item is image clarity. "Image clarity" refers to the sharpness of an image projected onto the surface of an object. High image clarity results in a clear image, while low image clarity results in a blurred image. For surfaces with high image clarity, the difference in the amount of specular and diffuse reflected light components in the light reflected from the light source is large, and the specular reflected light component has a strong directivity in the direction of reflection. On the other hand, for surfaces with low image clarity, the difference in the amount of specular and diffuse reflected light components in the light reflected from the light source is small, but the directivity of the specular reflected light component is relatively weak, resulting in a wider range of reflection directions. Therefore, when the surface clarity of an object being inspected is high, the lighting direction in gloss change inspections is limited to a direction that captures the specular reflected light component. Furthermore, for color change inspections and surface roughness change inspections, the lighting direction is limited to a direction that avoids the specular reflected light component.

[0022] So far, we have explained the case where the surface of the object to be inspected is assumed to be smooth. Therefore, if the entire surface of the object to be inspected is textured or has large irregularities such as curves or steps, the reflection direction of the light irradiated onto the surface may be strongly affected by the uneven surface. Therefore, in order to properly illuminate the object to be inspected, it is necessary to adjust the illumination direction depending on the shape of the surface of the object to be inspected, i.e., whether the surface texture is smooth or rough.

[0023] Taking into account the above-described inspection items and the influence of the surface characteristics of the inspection object on the inspection items, the illumination lighting pattern defined as the lighting conditions of the illumination device 116 during image capture in this embodiment will be described in detail. FIG. 3 shows the light source positions when the hemispherical illumination device 116 is viewed from the side, with black circles indicating light sources that are not lit and white circles indicating light sources that are lit. When there are multiple light sources that are lit, they are turned on one by one in sequence to capture multiple images of the inspection object. Furthermore, as shown in FIG. 2(b), multiple light source rows are arranged radially from 0 degrees to an axis passing through the center and zenith of the hemisphere at intervals of 45 degrees. For each row of radially arranged light sources, one light source is turned on one by one according to the lighting pattern shown in FIG. 3, and the inspection object is imaged in synchronization with the lighting of each light source.

[0024] Figure 3(a) shows the lighting patterns for the inspection items, which are divided into two categories: color change inspection or surface unevenness change inspection, and gloss change inspection, according to the difference in image clarity, which is a characteristic of the surface of the object being inspected.

[0025] The upper left of the table shown in Fig. 3(a) shows the illumination lighting pattern during imaging when the image clarity, which is a characteristic of the surface of the inspection object, is high in color change inspection or surface unevenness change inspection. This illumination lighting pattern is intended to obtain the diffuse reflection light component while avoiding the specular reflection light component of the light source light on the surface of the inspection object 202. When imaging the inspection object, the inspection object is directly faced to the imaging device 117, and among the light sources of the illumination device 116, the light source 301 closest to the optical axis of the imaging device 117 is not turned on, and the other light sources 302 are turned on sequentially.

[0026] The bottom left of the table in FIG. 3( a) shows the illumination lighting pattern for imaging when the image clarity, which is a characteristic of the surface of the inspection object, is low in a color change inspection or a surface unevenness inspection. In this case, to avoid the specular reflection light component of the light source light on the surface of the inspection object 202 and obtain the diffuse reflection light component, the light sources 305 around the zenith directly below the image capture device 117 and directly facing the inspection object 202 are not turned on, and the other light sources 306 are turned on sequentially. Of the light sources in the illumination device 116, the light source 305 is the light source that is closest to the optical axis of the image capture device 117 and has the largest elevation angle from the inspection object 202. Considering the spread of specular reflection light on a surface with low image clarity, the number of light sources 305 that are not turned on when image clarity is low is greater than the number of light sources 301 that are not turned on when image clarity is high.

[0027] 3(a) shows the illumination lighting pattern when imaging in a gloss change inspection when image clarity, which is a characteristic of the surface of the inspection object 202, is high. In this case, in order to acquire the specular reflection light component of the light source light on the surface of the inspection object 202, when imaging the inspection object 202, the light source 303 located directly below the imaging device 117 and directly facing the inspection object 202 is turned on, and the other light sources 304 are not turned on.

[0028] The lower right of FIG. 3( a) shows the illumination lighting pattern during imaging in a gloss change inspection when the image clarity, which is a characteristic of the surface of the inspection object 202, is low. In this case, to acquire the specularly reflected light component of the light source light on the surface of the inspection object 202, multiple light sources 307 located around the zenith directly below the image capture device 117 and directly facing the inspection object 202 are sequentially turned on to illuminate the surface of the inspection object, while other light sources 308 are not turned on. The light sources 307 are light sources with an elevation angle of a predetermined angle or more, including the light source that is closest to the optical axis of the image capture device 117 and has the largest elevation angle from the inspection object 202 among the light sources included in the illumination device 116. Considering the spread of specularly reflected light on a surface with low image clarity, the number of light sources 307 turned on when the image clarity is low is greater than the number of light sources 303 turned on when the image clarity is high.

[0029] Furthermore, when lighting up using the lighting pattern in gloss change inspection, it is not necessary to sequentially light up all of the rows of radially arranged light sources, regardless of the level of image clarity, which is a characteristic of the surface of the object being inspected, and only arbitrarily selected rows may be lighted up.

[0030] Figure 3(b) shows the lighting patterns corresponding to the surface characteristics of the object being inspected, dividing the inspection items into two categories: color change inspection, surface unevenness change inspection, and gloss change inspection.

[0031] The upper left of Fig. 3(b) shows an illumination pattern for imaging when the surface texture, which is a characteristic of the surface of the inspection object 202, is smooth in a color change inspection or a surface unevenness change inspection. In this case, the specular reflection light component of the light source light on the surface of the inspection object 202 is avoided and the diffuse reflection light component is acquired. Therefore, the surface of the inspection object is illuminated using an illumination pattern similar to that in the upper left of Fig. 3(a).

[0032] The lower left of Figure 3(b) shows an illumination lighting pattern during imaging when the surface texture, which is a characteristic of the surface of the inspection object 202, is rough in a color change inspection or a surface unevenness inspection. When the surface texture is rough and the surface orientation is not uniform, the specular reflection light component of the light source light on the surface of the inspection object 202 spreads more. Therefore, in order to avoid the specular reflection light component and obtain the diffuse reflection light component, the elevation angle is smaller than in the case of the lower left of Figure 3(a) where the surface texture is smooth, and even the light source 313 located at a lower position is turned on, while the other light sources 312 are not turned on.

[0033] The upper right of Fig. 3(b) shows an illumination pattern for gloss change inspection when the surface texture, which is a characteristic of the surface of the inspection object 202, is smooth, and obtains the specular reflection light component of the light source light on the surface of the inspection object 202. Therefore, the surface of the inspection object is illuminated using an illumination pattern similar to the upper left of Fig. 3(a).

[0034] The lower right of FIG. 3(b) shows the illumination pattern during imaging in a gloss change inspection when the surface texture, which is a characteristic of the surface of the inspection object 202, is rough. When the surface texture is rough, the orientation of the surface is not uniform, and the specular reflection light component of the light from the light source on the surface of the inspection object 202 spreads more. Therefore, in order to acquire the specular reflection light component, light source 314, which is located directly below the imaging device 117 and directly facing the inspection object, is turned on at a smaller elevation angle and lower position than in the lower right of FIG. 3(a) where the surface texture is smooth, and the other light sources 315 are not turned on.

[0035] When the surface has a rough and complex shape, the illumination pattern is sequentially applied to all of the rows of radially arranged light sources regardless of the type of inspection item. The same applies to illumination patterns for color change inspection or surface unevenness inspection when the surface has a smooth texture.

[0036] On the other hand, when the surface texture is smooth, the lighting pattern for gloss change inspection does not need to sequentially light up all of the rows of light sources arranged radially, but rather can light up only arbitrarily selected rows.

[0037] An example of the setting parameters for the illumination lighting pattern in this embodiment is shown in Figure 4. Setting parameter 401 is the setting parameter for the illumination lighting pattern when the image clarity, which is a characteristic of the surface of the object being inspected in the gloss change inspection, is low, as shown in the lower right of Figure 3(a).

[0038] The height on the vertical axis indicates the height of each light source in each light source row shown in FIG. 2(a), with the highest position being numbered "1" and the lowest position being numbered "8." The illumination angle on the horizontal axis indicates the angle around the axis passing through the center of the hemisphere and the zenith from the light source row at 0 degrees shown in FIG. 2(b). Therefore, one light source is specified by the number corresponding to the light source height on the vertical axis and the illumination angle on the horizontal axis. The setting parameters 401 shown in FIG. 4 define the order in which the light sources 307 to be turned on, shown in the lower right of FIG. 3(a), are turned on sequentially in the illumination angle direction, starting with the light source at the highest position, with the height gradually decreasing. Setting parameters are similarly defined for the other illumination patterns shown in FIG. 3 and stored in the RAM 103, HDD 113, various storage media mounted on the general-purpose drive 114, etc.

[0039] FIG. 5 shows a functional block diagram of an information processing device provided in the visual inspection device of this embodiment.

[0040] The surface feature setting unit 501 receives surface feature information of the object to be inspected set by the user, and outputs the surface feature information to the illumination lighting pattern setting unit 503 .

[0041] The inspection item setting unit 502 receives the inspection items for the appearance inspection set by the user, and outputs the inspection items to the illumination lighting pattern setting unit 503 and the image analysis unit 508. Note that the inspection items may be set in advance in the inspection item setting unit 502 instead of being set by the user.

[0042] The illumination lighting pattern setting unit 503 stores the illumination lighting pattern in memory as parameters that set the lighting positions and lighting sequences of the light sources, and selects the setting parameters for the illumination lighting pattern according to the inspection items for the visual inspection and the surface feature information of the object to be inspected.

[0043] The imaging condition setting unit 504 controls the illumination unit 505 and the imaging unit 506 according to the setting parameters of the illumination lighting pattern, and images the inspection object in synchronization with the lighting of each light source. The captured image data of the inspection object captured according to the illumination lighting pattern is stored in the storage unit 507.

[0044] The image analysis unit 508 analyzes the captured image data stored in the storage unit 507 to determine the evaluation feature amount required for analyzing the inspection items of the visual inspection set by the inspection item setting unit 502 .

[0045] The evaluation unit 509 evaluates the inspection items on the surface of the inspection object with respect to the evaluation feature amounts, judges whether the product is good or bad, and stores the inspection results in the storage unit 507 .

[0046] The display control unit 510 displays the test results stored in the storage unit 507 on the display 115 .

[0047] FIG. 6 shows a flowchart for explaining the appearance inspection process of this embodiment.

[0048] In S601, the surface feature setting unit 501 receives surface feature information of the object to be inspected, such as image clarity and surface texture, set by the user.

[0049] In S602, the illumination lighting pattern setting unit 503 acquires the characteristics of the surface of the inspection object from the surface characteristic information of the inspection object received from the user.

[0050] In S603, the inspection item setting unit 502 sets the inspection items for the visual inspection. Information indicating the inspection items may be received from the user and the received inspection items may be set, or the inspection items may be set in advance. The inspection item setting unit 502 outputs the set inspection items to the illumination lighting pattern setting unit 503 and the image analysis unit 508.

[0051] In S604, the image analysis unit 508 sets the type of evaluation feature for the set inspection item. As described above, the evaluation feature may be, for example, a specular reflection light component for a gloss change inspection, a diffuse reflection light component for a color change inspection, or the amount of surface unevenness, the amount of change in surface unevenness, or the area or size of the unevenness transformation for a surface unevenness change inspection.

[0052] In S605, the illumination lighting pattern setting unit 503 determines the illumination lighting pattern according to the inspection item and the surface feature information of the inspection object.

[0053] In S606, the imaging condition setting unit 504 determines, as imaging conditions, the illumination lighting pattern of the illumination unit 505 and imaging settings such as the shutter speed and exposure of the imaging unit 506. The imaging settings are determined according to, for example, the brightness of each light source 201 that is turned on, the number of light sources 201 that are turned on simultaneously, etc.

[0054] In S607, the imaging condition setting unit 504 turns on the illumination unit 505 in accordance with the imaging conditions determined in S606, and causes the imaging unit 506 to capture an image of the inspection object in synchronization with the lighting of the illumination unit 505. The captured image data obtained by imaging by the imaging unit 506 is stored in the storage unit 507.

[0055] In S608, the image analysis unit 508 sets an analysis method for analyzing the evaluation feature amount of the captured image data for the examination item set in S603.

[0056] In S609, the image analysis unit 508 analyzes each captured image data and calculates an evaluation feature amount based on the analysis method determined in S608.

[0057] In S610, the evaluation unit 509 performs defect determination for the inspection items set in S603 based on the evaluation feature amounts calculated in S609.

[0058] In S611, the evaluation unit 509 stores data relating to the inspection result in the storage unit 507 based on the defect determination result.

[0059] In S612, the display control unit 510 causes the display 115 to display a screen showing the test results based on the data relating to the test results stored in the storage unit 507.

[0060] In this embodiment, gloss change, color change, and surface irregularities are given as typical examples of defects, but other defects may occur depending on the type of object being inspected. In the case where the surface condition of the object being inspected affects the inspection results, the same effect as in this embodiment can be obtained for inspection items to detect such other defects by determining an appropriate illumination lighting pattern according to the surface feature information of the object being inspected.

[0061] As described above, according to the first embodiment, highly accurate visual inspection is possible by analyzing captured image data of an inspection object that has been appropriately illuminated in accordance with surface feature information of the inspection object during visual inspection.

[0062] [Embodiment 2] In the first embodiment, the illumination lighting pattern is determined according to two inspection object feature amounts, but in this embodiment, the illumination lighting pattern is determined according to surface feature information of two types of inspection objects. Note that the following description will focus on the differences from the first embodiment described above, and a description of the similarities will be omitted.

[0063] The illumination lighting patterns in this embodiment will be described in detail below.

[0064] FIG. 7(a) shows a lighting pattern corresponding to a combination of image clarity, which is a feature of the surface of the object to be inspected, and the surface texture of the object to be inspected in a color change inspection or a surface unevenness change inspection.

[0065] The upper left of Figure 7(a) is an illumination lighting pattern when the surface of the object to be inspected has high image clarity and a smooth surface texture, and is the same illumination lighting pattern as the upper left of Figure 3(a).

[0066] The lower left of FIG. 7(a) shows an illumination pattern when the surface of the object to be inspected has low image clarity and a smooth surface texture, and is the same illumination pattern as the lower left of FIG. 3(a).

[0067] The upper right of Figure 7(a) shows the illumination pattern when the surface of the object to be inspected has high image clarity and a rough surface texture, and is the same as the illumination pattern shown in the lower left of Figure 3(b).

[0068] The lower right of FIG. 7( a) shows an illumination pattern for an object 202 having a surface characterized by low image clarity and rough surface texture. Because of the low image clarity and rough surface texture, the specularly reflected light component of the light source light on the surface of the object 202 tends to spread. Therefore, the specularly reflected light component of light from a light source with a smaller elevation angle is incident on the image capture device 117 than when the image clarity is high and the surface texture is smooth. For this reason, in order to capture the diffusely reflected light component while avoiding the specularly reflected light component, the light sources 702 that are turned on are limited to those located lower and with an even smaller elevation angle than the light source 313 shown in the lower left of FIG. 3( b). Therefore, when capturing an image of the object 202, the light sources 702 located lower are turned on sequentially, and the other light sources 701 are not turned on.

[0069] The illumination pattern shown in FIG. 7(a) is such that all the rows of light sources arranged radially are sequentially lit.

[0070] FIG. 7(b) shows the illumination lighting pattern corresponding to the combination of image clarity, which is a feature of the surface of the object to be inspected, and the surface texture of the object to be inspected in the gloss change inspection.

[0071] The upper left of Figure 7(b) is an illumination lighting pattern when the surface of the object to be inspected has high image clarity and a smooth shape, and is the same illumination lighting pattern as the upper right of Figure 3(b).

[0072] The lower left of FIG. 7(b) is an illumination lighting pattern when the surface of the object to be inspected has low image clarity and a smooth shape, and is the same illumination lighting pattern as the lower right of FIG. 3(a).

[0073] The upper right of Figure 7(b) is an illumination pattern when the surface of the object to be inspected has high image clarity and a complex shape, and is the same illumination pattern as the lower right of Figure 3(b).

[0074] The lower right of FIG. 7( b) shows an illumination lighting pattern for an object 202 having low image clarity and rough surface texture. Because the surface of the object 202 has low image clarity and a rough surface texture, the specularly reflected light component of the light source light is likely to spread on the surface of the object 202. Therefore, more specularly reflected light components from light sources with smaller elevation angles are incident on the image capture device 117 than when the surface has high image clarity and a smooth surface texture. For this reason, in order to capture as many specularly reflected light components of the light source light as possible, the light sources 703 that are turned on are limited to those located lower and with smaller elevation angles than the light source 314 shown in the lower right of FIG. 3( b). Therefore, when capturing an image of the object 202, the light sources 703 that provide illumination from more directions are turned on sequentially, and the other light sources 704 are not turned on.

[0075] The illumination pattern shown in FIG. 7(b) is such that all the rows of light sources arranged radially are sequentially lit.

[0076] As described above, according to the second embodiment, highly accurate appearance inspection is possible by analyzing captured image data of an object that has been appropriately illuminated in accordance with multiple pieces of feature information on the surface of the object during appearance inspection.

[0077] [Embodiment 3] In the first and second embodiments, when the surface feature information is the same, the illumination patterns for the inspection items based on different reflected light components, i.e., color change inspection and surface unevenness inspection, and gloss change inspection, are mutually exclusive and do not overlap. However, the illumination patterns are not necessarily mutually exclusive for different inspection items, and the illumination light sources may partially overlap. Therefore, if an illumination pattern is set for each inspection item and the inspection object is imaged, imaging the same inspection object multiple times using the same light source, which is inefficient. Therefore, in this embodiment, if multiple different inspection items are set for the same inspection object and a light source is commonly illuminated in multiple illumination patterns corresponding to those inspection items, imaging using that common light source is performed only once. Note that differences from the first embodiment will be mainly described, and similarities will be omitted.

[0078] 8 shows a functional block diagram of an information processing device provided in the appearance inspection device of this embodiment. Processing other than the inspection item setting unit 502, the illumination lighting pattern setting unit 503, the imaging condition setting unit 504, and the captured image data extraction unit 801 is the same as in the first embodiment, and therefore description thereof will be omitted.

[0079] First, the inspection item setting unit 502 accepts settings of multiple inspection items. The illumination lighting pattern setting unit 503 sets multiple illumination lighting patterns for multiple inspection items according to the characteristics of the surface of the inspection object. The imaging condition setting unit 504 identifies a lighting light source common to the multiple illumination lighting patterns and controls the illumination unit 505 and the imaging unit 506 so that imaging using the common lighting light source is performed only once. The imaging condition setting unit 504 also outputs information related to the illumination lighting pattern corresponding to each inspection item to the captured image data extraction unit 801. The captured image data extraction unit 801 extracts captured image data of the inspection object captured according to the illumination lighting pattern corresponding to the inspection item according to the inspection item to be analyzed by the image analysis unit 508 and outputs the extracted image data to the image analysis unit 508. Note that in this embodiment, the captured image data extraction unit 801 is configured to acquire the illumination lighting pattern from the imaging condition setting unit 504, but may also be configured to acquire the illumination lighting pattern from the illumination lighting pattern setting unit 503.

[0080] FIG. 9 shows a flowchart for explaining the appearance inspection process of this embodiment.

[0081] The processes from S601 to S605, S607 to S608, and S609 to S612 are the same as those in the first embodiment, and therefore the description thereof will be omitted.

[0082] In S901, the imaging condition setting unit 504 determines a common lighting light source for the illumination lighting pattern for each examination item.

[0083] In S902, the imaging condition setting unit 504 determines imaging conditions so that imaging using a common lit light source is performed once.

[0084] In S903, the captured image data extraction unit 801 extracts, for each inspection item, captured image data of the inspection object captured in accordance with the illumination lighting pattern corresponding to the inspection item, and outputs the extracted image data to the image analysis unit 508.

[0085] In S609 and S610, the captured image data is analyzed and a defect determination is performed according to the inspection item corresponding to the captured image data output in S903. For example, the captured image data extraction unit 801 may add information about the inspection item to the captured image data to be output, and the image analysis unit 508 may set an analysis method for the captured image data based on the information about the inspection item added to the captured image data. Similarly, the image analysis unit 508 may add information about the inspection item to the calculated evaluation feature, and the evaluation unit 509 may perform a defect determination based on the information about the inspection item added to the evaluation feature.

[0086] As described above, according to the third embodiment, by analyzing the captured image data of the inspection object with an appropriate lighting direction set according to the feature quantities of the inspection object, it is possible to efficiently carry out a highly accurate appearance inspection.

[0087] [Embodiment 4] In the first to third embodiments, the illumination pattern is changed depending on the characteristics of the surface of the object to be inspected, and the captured image data may include captured image data that is not suitable for calculating the desired evaluation feature amount. In particular, when calculating the diffuse reflection light component excluding the specular reflection light component as the evaluation feature amount, it is desirable to exclude the captured image data that includes the specular reflection light component from the analysis target.

[0088] Therefore, in this embodiment, from the multiple captured image data obtained, only captured image data suitable for calculating the evaluation feature values ​​of the inspection item is extracted, and the extracted captured image data is analyzed to calculate the evaluation feature values.

[0089] The following description will focus on the processes that are different from those in the first embodiment, and will omit a description of the same processes.

[0090] Here, as an example of processing for determining whether or not a specular reflection light component is included in the light reflected from the light source on the surface of the object being inspected in the captured image data, a threshold value corresponding to the brightness of the specular reflection light component of the light reflected from the light source on the surface of the object being inspected is set for the brightness in the captured image data. Captured image data in which a brightness equal to or greater than the threshold is detected on the surface of the object being inspected is captured image data in which too much specular reflection light component is reflected, and is therefore captured image data that is not suitable for calculating evaluation feature quantities, and is therefore excluded from analysis targets for calculating evaluation feature quantities.

[0091] The method of determining whether or not to exclude captured image data from the analysis target may differ depending on the type of evaluation feature, and the threshold value or the like serving as the determination criterion may also be determined arbitrarily.

[0092] The functional block configuration of the visual inspection device in this embodiment is the same as the block configuration shown in FIG. 8 of the third embodiment.

[0093] When the surface of the inspection object is not smooth, the captured image data extraction unit 801 determines whether the captured image data is suitable for calculating an evaluation feature amount according to the inspection item in the image analysis unit 508. The captured image data extraction unit 801 outputs only captured image data that has been determined to be suitable for calculating an evaluation feature amount to the image analysis unit 508 as captured image data to be analyzed. Processing other than that in the captured image data extraction unit 801 is the same as in the first embodiment, and therefore description thereof will be omitted.

[0094] 10 shows a flowchart for explaining the appearance inspection process of this embodiment. The processes from S601 to S608 and S609 to S612 are the same as those in the first embodiment, and therefore the explanation will be omitted.

[0095] In S1001, the captured image data extraction unit 801 determines whether the surface of the inspection object is smooth. If it is determined that the surface of the inspection object is not smooth, the process proceeds to S1002, and if it is determined that the surface of the inspection object is smooth, the process proceeds to S609.

[0096] In S1002, the captured image data extraction unit 801 determines captured image data suitable for the evaluation feature amount analysis of the examination item, and acquires the captured image data as the captured image data to be analyzed.

[0097] As described above, according to the fourth embodiment, by analyzing only captured image data that is suitable for calculating evaluation feature quantities from among the captured image data obtained, highly accurate appearance inspection is possible.

[0098] (Other Examples) The present invention can also be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in the computer of the system or device read and execute the program.The present invention can also be realized by a circuit (e.g., ASIC) that realizes one or more functions.

[0099] The present disclosure includes the following configurations and methods. [Configuration 1] a control means for controlling an imaging means for imaging an object to be inspected and an illumination means having a plurality of light sources with different elevation angles from the object to be inspected; an acquisition means for acquiring characteristic information of the surface of the inspection object; Equipped with the control means sets lighting conditions for the lighting means based on the characteristic information and the inspection items for the inspection object, turns on the plurality of light sources of the lighting means in accordance with the set lighting conditions, and causes the imaging means to image the inspection object in synchronization with the lighting. 1. An information processing device comprising: [Configuration 2] the lighting condition is a condition for specifying a light source to be turned on among the plurality of light sources, 2. The information processing device according to configuration 1, [Configuration 3] the characteristic information includes information regarding at least one of image clarity and surface texture; 3. The information processing device according to configuration 1 or 2. [Configuration 4] The inspection item is any one of color change, surface roughness change, and gloss change. 4. The information processing device according to any one of configurations 1 to 3. [Configuration 5] the setting means sets the lighting conditions to be the same when the inspection item is the color change and when the inspection item is the surface unevenness change. 5. The information processing device according to configuration 4. [Configuration 6] and when the inspection item is the gloss change, the setting means sets the lighting conditions so that, as the image clarity of the inspection object becomes lower, the lighting conditions are set so that the light sources among the plurality of light sources are turned on in order from the light source having the largest elevation angle from the inspection object to the light source having the smallest elevation angle. 5. The information processing device according to configuration 4. [Configuration 7] When the inspection item is the gloss change, the setting means sets the lighting conditions so that, as the surface texture of the inspection object becomes rougher, light sources among the plurality of light sources are turned on in order from the light source having the largest elevation angle from the inspection object to the light source having the smallest elevation angle. 7. The information processing device according to configuration 4 or 6, [Configuration 8] When the inspection item is the color change or the surface unevenness change, the lower the image clarity of the inspection object, the more the setting means sets the lighting conditions so as not to light the light sources having the largest to smallest elevation angles from the inspection object among the plurality of light sources. 5. The information processing device according to configuration 4. [Configuration 9] When the inspection item is the color change or the surface unevenness change, the rougher the surface texture of the inspection object, the more the setting means sets the lighting conditions so as not to light the light sources having the largest to smallest elevation angles from the inspection object among the plurality of light sources. 9. The information processing device according to configuration 4 or 8. [Configuration 10] The illumination means has the plurality of light sources arranged in a hemispherical shape, The imaging means is disposed at the zenith of the lighting means. 10. The information processing device according to any one of configurations 1 to 9. [Configuration 11] When a plurality of different inspection items are set for the same inspection object and a light source that is commonly turned on for the plurality of different inspection items exists, the control means turns on the light source and captures an image synchronized with the turning on only once. 11. The information processing device according to any one of configurations 1 to 10. [Configuration 12] the acquiring means includes a receiving means for receiving an input from a user, and acquires the input from the user regarding the surface features of the inspection object received by the receiving means as the feature information. 12. The information processing device according to any one of configurations 1 to 11. [Configuration 13] Further, an inspection means for performing an appearance inspection based on the captured image obtained by the imaging means is provided, the inspection means performs the visual inspection only on the captured images that are suitable for the visual inspection, among the captured images. 13. The information processing device according to any one of configurations 1 to 12. [Configuration 14] The information processing device according to any one of configurations 1 to 13, the imaging means; the lighting means; An appearance inspection device comprising: [Configuration 15] a step of controlling an imaging means for imaging an object to be inspected and an illumination means having a plurality of light sources with different elevation angles from the object to be inspected; acquiring surface feature information of the inspection object; Equipped with the controlling step includes setting lighting conditions for the lighting means based on the characteristic information and an inspection item for the inspection object, lighting the plurality of light sources of the lighting means in accordance with the set lighting conditions, and causing the imaging means to image the inspection object in synchronization with the lighting. An information processing method comprising: [Configuration 16] A program for causing a computer to function as the information processing device according to any one of configurations 1 to 13.

Claims

1. a control means for controlling an imaging means for imaging an object to be inspected and an illumination means having a plurality of light sources with different elevation angles from the object to be inspected; an acquisition means for acquiring characteristic information of the surface of the inspection object; Equipped with the control means sets lighting conditions for the lighting means based on the characteristic information and the inspection items for the inspection object, turns on the plurality of light sources of the lighting means in accordance with the set lighting conditions, and causes the imaging means to image the inspection object in synchronization with the lighting.

1. An information processing device comprising:

2. the lighting condition is a condition for specifying a light source to be turned on among the plurality of light sources, 2. The information processing apparatus according to claim 1, wherein:

3. the characteristic information includes information regarding at least one of image clarity and surface texture; 2. The information processing apparatus according to claim 1, wherein:

4. The inspection item is any one of a color change, a surface unevenness change, and a gloss change.

2. The information processing apparatus according to claim 1, wherein:

5. the setting means sets the lighting conditions to be the same when the inspection item is the color change and when the inspection item is the surface unevenness change.

5. The information processing apparatus according to claim 4,

6. and when the inspection item is the gloss change, the setting means sets the lighting conditions so that, as the image clarity of the inspection object becomes lower, the lighting conditions are set so that the light sources among the plurality of light sources are turned on in order from the light source having the largest elevation angle from the inspection object to the light source having the smallest elevation angle.

5. The information processing apparatus according to claim 4,

7. When the inspection item is the gloss change, the setting means sets the lighting conditions so that, as the surface texture of the inspection object becomes rougher, light sources among the plurality of light sources are turned on in order from the light source having the largest elevation angle from the inspection object to the light source having the smallest elevation angle.

5. The information processing apparatus according to claim 4,

8. When the inspection item is the color change or the surface unevenness change, the lower the image clarity of the inspection object, the more the setting means sets the lighting conditions so as not to light the light sources having the largest to smallest elevation angles from the inspection object among the plurality of light sources.

5. The information processing apparatus according to claim 4,

9. When the inspection item is the color change or the surface unevenness change, the rougher the surface texture of the inspection object, the more the setting means sets the lighting conditions so as not to light the light sources having the largest to smallest elevation angles from the inspection object among the plurality of light sources.

5. The information processing apparatus according to claim 4,

10. The illumination means has the plurality of light sources arranged in a hemispherical shape, The imaging means is disposed at the zenith of the lighting means.

2. The information processing apparatus according to claim 1, wherein:

11. When a plurality of different inspection items are set for the same inspection object and a light source that is commonly turned on for the plurality of different inspection items exists, the control means turns on the light source and captures an image synchronized with the turning on only once.

2. The information processing apparatus according to claim 1, wherein:

12. the acquiring means includes a receiving means for receiving an input from a user, and acquires the input from the user regarding the surface features of the inspection object received by the receiving means as the feature information.

2. The information processing apparatus according to claim 1, wherein:

13. Further, an inspection means for performing an appearance inspection based on the captured image obtained by the imaging means is provided, the inspection means performs the visual inspection only on the captured images that are suitable for the visual inspection, among the captured images.

2. The information processing apparatus according to claim 1, wherein:

14. An information processing device according to any one of claims 1 to 13; the imaging means; the lighting means; An appearance inspection device comprising:

15. a step of controlling an imaging means for imaging an object to be inspected and an illumination means having a plurality of light sources with different elevation angles from the object to be inspected; acquiring surface feature information of the inspection object; Equipped with the controlling step includes setting lighting conditions for the lighting means based on the characteristic information and an inspection item for the inspection object, lighting the plurality of light sources of the lighting means in accordance with the set lighting conditions, and causing the imaging means to image the inspection object in synchronization with the lighting. An information processing method comprising:

16. A program for causing a computer to function as the information processing device according to any one of claims 1 to 13.

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