JP2021183947A - Defect inspection device and defect inspection method - Google Patents

Abstract

To allow a human to determine a state of raw materials, such as color of colored defects and the color of an inspection target displayed on a screen.SOLUTION: A defect inspection device comprises: a first lighting device irradiating a detection target with first light at an irradiation angle θ; a second lighting device irradiating a site irradiated with the first light, with second light at an irradiation angle α different from the irradiation angle θ; a line type color sensor receiving reflected light of the first light obtained by regularly reflecting the first light and reflected light of the second light obtained by diffusing and reflecting the second light; and a defect detection part calculating upper limit y1 and lower limit y2 of received light volume ratio y capable of identifying defective colors of RGB three primary colors with respect to glossiness x of the detection target calculated based on received light volume A of the reflected light of the first light and received light volume B of the reflected light of the second light, and controlling the lighting of at least one of the first lighting device and the second lighting device so that the sum of received light volume a of the reflected light of the first light and received light volume b of the reflected light of the second light calculated based on the received light volume ratio y within the range of y1>y>y2 is equal to total received light volume in the line type color sensor.SELECTED DRAWING: Figure 1

Description

The present invention relates to a defect inspection device and a defect inspection method for inspecting an inspected object so that a person can discriminate the material state such as the color of a colored defect and the color of the inspected object on an inspection screen.

The technique of inspecting an inspected object by an inspection device using a line type color sensor is well known. For example, in Patent Document 1 below, a light source provided so as to positively reflect the light irradiating the object to be inspected (hereinafter, also referred to as “normal reflection illumination”) and the light irradiating the inspection object are scattered and reflected. A technique for distinguishing between ink printing on a substrate and a metal region is disclosed in an optical system using a light source (hereinafter, also referred to as “scattered reflection illumination”) provided as described above.

Japanese Unexamined Patent Publication No. 2008-21605

Here, in an optical system using specular reflection illumination and scattered reflection illumination as in Patent Document 1, a line-type color sensor is used to distinguish between ink printing on a substrate and a metal region, and an inspected object is inspected. It is possible. However, a technique for discriminating the material state such as the color of the detected defect and the color of the inspected object on the screen has not been established.
For example, if the output of specular illumination is strong when a colored defect is detected, the defect will be displayed on the screen as a dark defect (black), and it is difficult to determine the color of the defect on the screen even if a color inspection is performed. It becomes.
Further, if the output of the scattered reflection illumination is strong when a colored defect is detected, the defect is displayed on the screen as a bright defect (white), and it is also difficult to determine the color of the defect on the screen. Therefore, in order for a person to discriminate the color of the detected defect on the screen, it is necessary to appropriately control the output ratio of the specular illumination and the diffuse reflection illumination.

The present invention has been made in view of such circumstances, and an object thereof is to allow a person to discriminate a material state such as a color of a colored defect in an inspected object displayed on a screen and a color of the inspected object. It is an object of the present invention to provide a possible defect inspection apparatus and defect inspection method.

In order to solve the above-mentioned problems, the defect inspection apparatus of the present invention has a first illumination that irradiates the object to be inspected with the first light at an irradiation angle θ, and a position where the first light is irradiated. On the other hand, the second illumination that irradiates the second light at an irradiation angle α different from the irradiation angle θ, and the first light that is generated by positive reflection of the first light irradiated to the object to be inspected. A line-type color sensor that receives the reflected light of light and the reflected light of the second light generated by scattering and reflecting the second light irradiated to the object to be inspected, and the first in the line-type color sensor. The glossiness x (x = A ÷ B) of the inspected object is calculated based on the received amount A of the reflected light of 1 and the received amount B of the reflected light of the second light, and the gloss of the inspected object is calculated. _{The upper limit value y 1} and the lower limit value y ₂ of the light receiving amount ratio y capable of discriminating the color of the defect of the RGB3 primary color with respect to the degree x are calculated, and the line is based on the light receiving amount ratio y within the range of _{y 1} >y> y _2. The light receiving amount a of the reflected light of the first light and the light receiving amount b of the reflected light of the second light in the type color sensor are calculated, and the sum of the light receiving amount a and the light receiving amount b is the line type color. It has a defect detection unit that adjusts the dimming of at least one of the first illumination and the second illumination so as to obtain the total amount of light received by the sensor.

Further, according to the present invention, in the defect inspection device, the irradiation angle θ is such that the first light irradiated to the inspected object and the first light are applied to the inspected object. The irradiation angle α is an angle formed by the normal line at a vertical position, and the irradiation angle α is an angle formed by the second light irradiated to the object to be inspected and the normal line, and is the line type color sensor. The light receiving angle θ of the reflected light of the first light received by is an angle formed by the reflected light of the first light and the normal line, and the light receiving angle θ is −θ with reference to the normal line. When the irradiation angle θ is + θ degree, the second illumination has an angle within the range of −90 degree <α <−θ degree, −θ degree <α <+ θ degree. It is provided so that the angle is within the range, or the angle is within the range of + θ degree <α <+ 90 degrees.

In order to solve the above-mentioned problems, in the defect inspection method of the present invention, the first illumination irradiates the object to be inspected with the first light at the irradiation angle θ, and the second illumination is described above. The second light is irradiated to the position where the first light is irradiated at an irradiation angle α different from the irradiation angle θ, and the line type color sensor irradiates the object to be inspected with the first light. To receive the reflected light of the first light generated by the normal reflection of the light and the reflected light of the second light generated by the scattered reflection of the second light irradiated to the object to be inspected. The defect detecting unit determines the glossiness x (x =) of the object to be inspected based on the received amount A of the reflected light of the first light and the received amount B of the reflected light of the second light in the line type color sensor. _{A ÷ B) is calculated, and the upper limit value y 1} and the lower limit value y ₂ of the light receiving amount ratio y that can discriminate the color of the defect of the RGB3 primary color with respect to the glossiness x of the inspected object are calculated, and y ₁ >y>. Based on the light receiving amount ratio y within the range of y ₂ , the light receiving amount a of the reflected light of the first light and the light receiving amount b of the reflected light of the second light in the line type color sensor are calculated, and the light receiving amount b. It includes dimming at least one of the first illumination and the second illumination so that the sum of a and the light receiving amount b is the total light receiving amount in the line type color sensor. ..

According to the present invention, a person can discriminate the material state such as the color of a colored defect in the inspected object displayed on the screen and the color of the inspected object.

It is a schematic block diagram which shows the structure of a defect inspection apparatus. It is an optical block diagram of the image pickup part. It is a table which shows the specific example of the equipment used. It is a table which shows the specific example of the inspection condition. It is a table which shows the specific example of the object to be inspected. It is a table explaining the relationship between the light-receiving amount and the light-receiving amount ratio from specular reflection illumination and diffuse reflection illumination. It is a table explaining the glossiness of the object to be inspected. It is a figure which shows the colored defect in the inspected object. It is a figure which shows the relationship between the light-receiving amount ratio of the light-receiving amount from specular reflection illumination and diffuse reflection illumination, and the defect light amount Lv when the object to be inspected is an iron plate (glossiness: 0.5). It is a figure which shows the relationship between the light-receiving amount ratio of the light-receiving amount from specular reflection illumination and diffuse reflection illumination, and the defect light amount Lv when the object to be inspected is a zinc-plated iron plate (glossiness: 0.9). It is a figure which shows the relationship between the light-receiving amount ratio of the light-receiving amount from specular reflection illumination and diffuse reflection illumination, and the defect light amount Lv when the object to be inspected is a phosphorus bronze plate (glossiness: 5.7). It is a figure which shows the relationship between the light-receiving amount ratio of the light-receiving amount from specular reflection illumination and diffuse reflection illumination, and defect light amount Lv when the object to be inspected is an aluminum plate (glossiness: 10.2). It is a figure which shows the relationship between the light-receiving amount ratio of the light-receiving amount from specular reflection illumination and diffuse reflection illumination, and the defect light amount Lv when the object to be inspected is a copper plate (glossiness: 11.4). It is a figure which shows the relationship between the light-receiving amount ratio of the light-receiving amount from specular reflection illumination and diffuse reflection illumination, and defect light amount Lv when the object to be inspected is a stainless steel plate (glossiness: 23.6). It is a figure which shows the relationship between the glossiness and the light-receiving amount ratio of the light-receiving amount from the specular reflection illumination and the diffuse reflection illumination which are effective. 6 is a table showing the glossiness of other objects to be inspected when the glossiness of the phosphor bronze plate is "1.00". It is a figure which shows the relationship between the glossiness when the glossiness of a phosphorus bronze plate is "1.00", and the light-receiving amount ratio of the light-receiving amount from the specular reflection illumination and the diffuse reflection illumination. It is a table which shows the δ value and φ value according to the numerical fluctuation of the glossiness of a phosphor bronze plate. It is a table which shows the inspection result for each light-receiving amount ratio of the oil defect adhering to a copper plate. It is a figure which shows the waveform which averaged the output of each color of a line type color sensor when the light-receiving amount ratio of the light-receiving amount from a specular reflection illumination and the diffuse reflection illumination is 10: 0. It is a figure which shows the waveform of the output of each color of a line type color sensor when the light-receiving amount ratio of the light-receiving amount from a specular reflection illumination and the diffuse reflection illumination is 10: 0. It is a figure which shows the waveform which averaged the output of each color of a line type color sensor when the light-receiving amount ratio of the light-receiving amount from a specular reflection illumination and the diffuse reflection illumination is 8: 2. It is a figure which shows the waveform of the output of each color of a line type color sensor when the light-receiving amount ratio of the light-receiving amount from a specular reflection illumination and the diffuse reflection illumination is 8: 2. It is a figure which shows the waveform which averaged the output of each color of a line type color sensor when the light-receiving amount ratio of the light-receiving amount from a specular reflection illumination and the diffuse reflection illumination is 3: 7. It is a figure which shows the waveform of the output of each color of a line type color sensor in the case where the light-receiving amount ratio of the light-receiving amount from a specular reflection illumination and the diffuse reflection illumination is 3: 7.

Hereinafter, a defect inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing a configuration of a defect inspection device. As shown in FIG. 1, the defect inspection device 1 includes an image pickup unit 2, a defect detection unit 11, a rotary encoder 12, and an operation unit 13.

The defect inspection device 1 is a device that inspects the inspected object 14.
The object to be inspected 14 is, for example, a continuous sheet. As an example of the object to be inspected 14 in the form of a continuous sheet, products such as metal and film can be mentioned. The object to be inspected 14 has a long shape in the transport direction described later. The short axis direction of the object to be inspected 14 corresponds to the width direction, and the long axis (long) direction corresponds to the transport direction (also referred to as a traveling direction).

The image pickup unit 2 includes a lighting device that illuminates the object 14 to be inspected 14 and a line-type sensor that receives the reflected light thereof. The lighting device of the present embodiment includes lighting for specular reflection (hereinafter, also referred to as “specular reflection lighting”) and lighting for diffuse reflection (hereinafter, also referred to as “scattered reflection lighting”). The specular reflection illumination (first illumination) is provided so that the light irradiated to the object 14 to be inspected is specularly reflected. The diffuse reflection illumination (second illumination) is provided so that the light irradiated to the object 14 to be inspected is scattered and reflected. The shape of each illuminating device is, for example, a line type. The longitudinal direction of the imaging range of the imaging unit 2 is provided so as to be orthogonal to the traveling direction of the object to be inspected 14.
As the lighting device, for example, a fluorescent lamp, quartz rod lighting, LED lighting and the like are used. As the line type sensor, for example, a sensor having 2048 to 8192 elements is used. As the number of elements, an appropriate number of elements and speed (for example, data rate, scan rate, etc.) are used for a predetermined number of elements according to the width, traveling speed, resolution, installation space, etc. of the object 14 to be inspected. .. Further, the line type sensor receives the reflected light reflected by the object 14 to be inspected by the light emitted from the lighting device. The light received by the line type sensor is received in a state where the object to be inspected 14 is conveyed in the conveying direction. The line type sensor outputs an electric signal (defect data) according to the shade of the color tone of the surface of the object to be inspected 14 to the defect detection unit 11. In other words, the line type sensor outputs an electric signal according to the light intensity distribution on the surface of the inspected object 14 in units of lines (hereinafter referred to as inspection lines) in a direction orthogonal to the traveling direction of the inspected object 14. .. Examples of the line type sensor include a CMOS (complementary MOS) camera and a CCD (Charge-Coupled Device) camera.
In addition, the line type color sensor includes a three-line method, a prism spectroscopy method, and a Bayer method, and has built-in red, green, and blue sensors.

The defect detection unit 11 is composed of an image processing computer and an image board connected to the line type sensor of the image pickup unit 2. The defect detection unit 11 detects the defect of the inspected object 14 based on the image data obtained from the line type sensor. The defect detection unit 11 includes, for example, a binarization unit, a run-length coding unit, and a connectivity processing unit. The defect detection unit 11 binarizes the defect data input from the line type sensor of the image pickup unit 2 based on a predetermined threshold value, compresses the defect data, performs a connectivity process, and performs a defect feature amount. (Information representing the characteristics of the shape of the defect. For example, the peripheral length, area, width, length, aspect ratio, area ratio of the defect) is measured.
In addition to defect detection, the defect detection unit 11 calculates the glossiness of the surface (light irradiation surface) of the object 14 to be inspected based on the amount of light received from the specular reflection illumination and the amount of light received from the diffuse reflection illumination. Further, the defect detection unit 11 performs dimming (automatic dimming) of each illumination based on the light receiving amount (camera light receiving amount) in the line type sensor at the start of inspection.
As the defect detection unit 11, an image processing device LSC-600 manufactured by MEC Co., Ltd. can be used.

The rotary encoder 12 mainly contacts the wheel of the measuring unit owned by the rotary encoder 12 with the transfer roll, and measures the inspection length based on the rotation speed of the transfer roll. This transport roll transports the object to be inspected 14 in the transport direction. Here, the inspection length represents the distance from the inspection start position of the inspected object 14 in the Y-axis direction.

The operation unit 13 is for setting inspection conditions, displaying a screen during inspection, confirming past inspection results, and the like. In addition, defect detailed data, lists and maps, defect images, etc. are displayed as screen displays during inspection.

<Example>
FIG. 2 is an optical configuration diagram of the image pickup unit 2 of the present invention. The image pickup unit 2 includes a specular reflection illumination 22, a scattering reflection illumination 23, and a line type color sensor 21.
The specular reflection illumination 22 irradiates the object 14 to be inspected with light (first light) at an irradiation angle θ. The irradiation angle θ is an angle formed by the light emitted by the specular reflection illumination 22 on the object to be inspected 14 and the normal line 24 at the position where the light is applied to the object to be inspected 14.
The diffuse reflection illumination 23 irradiates the object 14 to be inspected with light (second light) at an irradiation angle α. The diffuse reflection illumination 23 irradiates the position where the specular reflection illumination 22 irradiates the light. The irradiation angle α is an angle formed by the light emitted by the scattered reflection illumination 23 on the object 14 to be inspected and the normal line 24. The irradiation angle α is an angle different from the irradiation angle θ.
In the line type color sensor 21, the reflected light generated by the normal reflection of the light emitted by the normal reflection illumination 22 on the inspected object 14 and the light emitted by the scattered reflection illumination 23 are scattered and reflected by the inspected object 14. Receives the generated reflected light. The line type color sensor 21 receives the reflected light of the light emitted by the specular reflection illumination 22 at the light receiving angle θ. The light receiving angle θ is an angle formed by the reflected light of the light emitted by the specularly reflected illumination 22 and the normal line 24.
The normal line 24 is a reference in which the irradiation angle θ, the irradiation angle α, and the light receiving angle θ are 0 degrees. In this embodiment, the irradiation angle θ of the light emitted by the specular reflection illumination 22 and the light reception angle θ of the reflected light received by the line type color sensor 21 are 15 degrees, and the irradiation angle α of the light emitted by the scattered reflection illumination 23 is α. Is assumed to be 0 degrees.

In this embodiment, the irradiation angle θ of the specular reflection illumination 22 and the line type color sensor 21 is set to 15 degrees, but the present invention is not limited to this. The smaller the angle, the less the optical axis shift due to the vertical movement of the object to be inspected 14 during transportation, so 15 degrees is practically adopted.
Further, although the irradiation angle of the diffuse reflection illumination 23 is set to 0 degrees, any angle may be used as long as the regular reflected light does not enter the line type color sensor 21. For example, the normal line 24 in FIG. 2 is used as a reference for the irradiation angle θ, the irradiation angle α, and the light receiving angle θ to be 0 degrees, the light receiving angle of the line type color sensor 21 is −θ degrees, and the light emitted by the specular reflection illumination 22. The irradiation angle of is + θ degree. In this case, the diffuse reflection illumination 23 has an irradiation angle α within a range of −90 degrees <α <−θ degrees (α1 in FIG. 2) and a range of −θ degrees <α <+ θ degrees (α2 in FIG. 2). It is provided so that the angle is within the range of + θ degree <α <+ 90 degree (α3 in FIG. 2). At this time, the imaging position of the line type color sensor 21 is fixed.

Here, with reference to FIGS. 3 to 5, specific examples of the equipment used, the inspection conditions, and the object to be inspected in this embodiment will be described.
FIG. 3 is a table showing specific examples of the equipment used. In the table shown in FIG. 3, the configuration of the defect inspection device 1, the name of the equipment used as each configuration, and the model of each equipment are shown.
An image processing apparatus (LSC-600) manufactured by MEC Co., Ltd. is used as the defect detection unit 11. As the line type color sensor 21, a line type sensor camera (2048,000 pixels, 80 MHz) manufactured by MEC Co., Ltd. and a lens (50 mm lens for line type sensor F2.8) are used. As the specular reflection illumination 22, LED illumination for lines (MLD-WA-W) manufactured by MEC Co., Ltd. is used. As the diffuse reflection illumination 23, LED illumination for lines (MLDHB-W1) manufactured by MEC Co., Ltd. is used. The brightness of the diffuse reflection optical system is darker than that of the specular reflection optical system. Therefore, as the diffuse reflection illumination 23 of this embodiment, illumination brighter than the specular reflection illumination 22 is used. For example, as shown in FIG. 3, the light intensity (brightness) of the diffuse reflection illumination 23 (MLDHB-W1) is 45 times the light intensity of the specular reflection illumination 22 (MLD-WA-W).
The configuration of the defect inspection device 1, the name of the equipment used as each configuration, and the model of each equipment are not limited to these examples.

FIG. 4 is a table showing specific examples of inspection conditions. FIG. 4 shows a device for setting inspection conditions, a name of the condition, and a content of the condition.
The inspection conditions for the defect inspection device 1 include an optical system, a camera angle, a specular reflection illumination angle, a scattered reflection illumination angle, a camera resolution, a camera distance, a specular reflection illumination distance, and a scattered reflection illumination distance. The condition of the optical system is to use specular reflection and diffuse reflection together. The condition of the camera angle is that the angle of the camera is 15 degrees. The condition of the specular illumination angle is that the angle of the specular illumination 22 is 15 degrees. The condition of the diffuse reflection illumination angle is that the angle of the diffuse reflection illumination 23 is 0 degree. The condition of the camera resolution is that the width direction is 100 μm / pixel and the flow direction is 100 μm / scan. The condition of the camera distance is that the distance to the inspection target is 498 mm. The condition of the specular illumination distance is that the distance to the inspection target is 200 mm. The condition of the diffuse reflection illumination distance is that the distance to the inspection target is 270 mm.
As an inspection condition for the rewinding machine, there is a transport speed. The condition of the transport speed is 5 m / min.
The equipment for setting inspection conditions, the name of the condition, and the content of the condition are not limited to these examples.

FIG. 5 is a table showing a specific example of the object to be inspected 14. FIG. 5 shows No. of the inspected object 14, the inspected object 14, and remarks.
As shown in FIG. 5, in this embodiment, No. 1-No. The inspection is performed on the six inspected objects 14 of No. 6. No. The object 14 to be inspected in 1 is an iron plate. No. The object 14 to be inspected in 2 is a galvanized iron plate (galvanized steel plate). No. The object 14 to be inspected in 3 is a phosphor bronze plate (JIS C5911). No. The object 14 to be inspected in 4 is an aluminum plate (aluminum alloy 1000 series). No. The object 14 to be inspected in 5 is a copper plate (copper alloy C1000 series). No. The object 14 to be inspected in 6 is a stainless steel plate (austenite 304 series).
In this embodiment, the defect inspection is performed using a metal product as the inspected object 14, but a non-metal product may be used as the inspected object 14.

The light emitted from the specular reflection illumination 22 and the scattered reflection illumination 23 is reflected by the object 14 to be inspected. The reflected light reflected by the object 14 to be inspected is received by the line type color sensor 21. The defect detection unit 11 adjusts (dimming) the irradiation amounts of the specular reflection illumination 22 and the scattered reflection illumination 23 based on the received light amount Lv of the line type color sensor 21. In the following, the received amount of the reflected light of the light emitted from the normal reflection illumination 22 before dimming is "light receiving amount A", and the received amount of the reflected light of the light emitted from the scattered reflected illumination 23 before dimming is "light receiving amount A". Is indicated as "light receiving amount B". Further, the received amount of the reflected light of the light emitted from the normal reflection illumination 22 after dimming is "light receiving amount a", and the received amount of the reflected light of the light emitted from the scattered reflected illumination 23 after dimming is "light receiving amount a". Amount b "is shown.

The defect detection unit 11 calculates the glossiness x of the object to be inspected 14 based on the light receiving amount A and the light receiving amount B in the line type color sensor 21. Defect detecting section 11 calculates the upper limit value y ₁ and the lower limit value y ₂ glossiness distinguishable received light amount ratio color defects RGB3 primary for x y of the object 14. The defect detection unit 11 calculates the light receiving amount a and the light receiving amount b in the line type color sensor 21 based on the light receiving amount ratio y within the range of _{y 1} >y> y _2. The defect detection unit 11 adjusts at least one of the specular reflection illumination 22 and the diffuse reflection illumination 23 so that the sum of the light reception amount a and the light reception amount b is the total light reception amount in the line type color sensor. When the irradiation amount of the specular reflection illumination 22 is already the irradiation amount of the light receiving amount a at the time of dimming, the defect detection unit 11 does not have to adjust the dimming of the specular reflection illumination 22. Further, when the irradiation amount of the scattering reflection illumination 23 is already the irradiation amount of the light receiving amount b at the time of dimming, the defect detection unit 11 does not have to perform the dimming of the scattering reflection illumination 23. When dimming of both the specular reflection illumination 22 and the scattered reflection illumination 23 is required at the time of dimming, the defect detection unit 11 performs dimming of both the specular reflection illumination 22 and the scattered reflection illumination 23.

Here, with reference to FIG. 6, the relationship between the light receiving amount a from the specular reflection illumination 22 and the light receiving amount b from the diffuse reflection illumination 23 will be described. FIG. 6 is a table for explaining the relationship between the light receiving amount and the light receiving amount ratio from the specular reflection illumination 22 and the diffuse reflection illumination 23.

In this embodiment, the ratio of the light receiving amount a from the specular reflection illumination 22 and the light receiving amount b from the diffuse reflection lighting 23 (light receiving amount a: light receiving amount b) is changed from 10: 0 to 0:10 to cause a colored defect. 3 was detected.
The output of the line type color sensor 21 is 0 Lv to 256 Lv (gradation). In this embodiment, the total light-receiving amount z (z = a + b) of the light-receiving amount a from the specular reflection illumination 22 and the light-receiving amount b from the diffuse reflection illumination 23 is set to 128 Lv, which is the center of 256 Lv. This is to make it easier for a person to discriminate the material state such as the color of the object to be inspected 14.

As shown in FIG. 6, when the light receiving amount ratio is 10: 0, the light receiving amount a is 128 Lv and the light receiving amount b is 0 Lv. When the light receiving amount ratio is 9: 1, the light receiving amount a is 115 Lv and the light receiving amount b is 13 Lv. When the light receiving amount ratio is 8: 2, the light receiving amount a is 102 Lv and the light receiving amount b is 26 Lv. When the light receiving amount ratio is 7: 3, the light receiving amount a is 90 Lv and the light receiving amount b is 38 Lv. When the light receiving amount ratio is 6: 4, the light receiving amount a is 77 Lv and the light receiving amount b is 51 Lv. When the light receiving amount ratio is 5: 5, the light receiving amount a is 64 Lv and the light receiving amount b is 64 Lv. When the light receiving amount ratio is 4: 6, the light receiving amount a is 51 Lv and the light receiving amount b is 77 Lv. When the light receiving amount ratio is 3: 7, the light receiving amount a is 38 Lv and the light receiving amount b is 90 Lv. When the light receiving amount ratio is 2: 8, the light receiving amount a is 26 Lv and the light receiving amount b is 102 Lv. When the light receiving amount ratio is 1: 9, the light receiving amount a is 13 Lv and the light receiving amount b is 115 Lv. When the light receiving amount ratio is 0:10, the light receiving amount a is 0 Lv and the light receiving amount b is 128 Lv.

FIG. 7 is a table for explaining the glossiness of the object to be inspected 14. FIG. 7 shows No. of the object 14 to be inspected, the object 14 to be inspected, the amount of light received from the specular reflection illumination 22, the amount of light received from the diffuse reflection illumination 23, and the glossiness x (x = A ÷ B). ing.

The glossiness x in the present invention is a value indicating the ratio of the light receiving amount A from the specular reflection illumination 22 and the light receiving amount B from the diffuse reflection illumination 23 in the line type color sensor 21 of the imaging unit 2. The defect detection unit 11 calculates the glossiness x by dividing the light receiving amount A by the light receiving amount B (x = A ÷ B). The glossiness x indicates that the larger the value of the inspected object 14, the more glossy the inspected object 14.
When the light receiving amount A from the specular reflection illumination 22 is measured, the scattered reflection illumination 23 is turned off. Further, when the light receiving amount B from the scattered reflection illumination 23 is measured, the specular reflection illumination 22 is turned off. Further, the outputs of the specular reflection illumination 22 and the scattered reflection illumination 23 at the time of measuring each received light amount are constant. Further, the scanning cycle of the line type color sensor 21 is also constant.

As shown in FIG. 7, No. In the iron plate 1, the light receiving amount A from the specular reflection illumination 22 is 44.5 Lv, the light receiving amount B from the diffuse reflection illumination 23 is 91.0 Lv, and the glossiness x is 0.5. No. In the zinc-plated iron plate of 2, the light receiving amount A from the specular reflection illumination 22 is 98.0 Lv, the light receiving amount B from the diffuse reflection illumination 23 is 115.0 Lv, and the glossiness x is 0.9. No. In the phosphorus bronze plate of No. 3, the light receiving amount A from the specular reflection illumination 22 is 134.0 Lv, the light receiving amount B from the diffuse reflection illumination 23 is 23.4 Lv, and the glossiness x is 5.7. No. In the aluminum plate No. 4, the light receiving amount A from the specular reflection illumination 22 is 189.0 Lv, the light receiving amount B from the scattered reflection illumination 23 is 18.5 Lv, and the glossiness x is 10.2. No. In the copper plate 5, the light receiving amount A from the specular reflection illumination 22 is 140.0 Lv, the light receiving amount B from the scattered reflection illumination 23 is 12.3 Lv, and the glossiness x is 11.4. No. In the stainless steel plate No. 6, the light receiving amount A from the specular reflection illumination 22 is 136.0 Lv, the light receiving amount B from the scattered reflection illumination 23 is 5.8 Lv, and the glossiness x is 23.6.

FIG. 8 is a diagram showing colored defects in the inspected object 14. In the embodiment, the red defect 31, the green defect 32, and the blue defect 33, the colored defects 3 of the RGB3 primary colors, were attached to each of the objects to be inspected 14.
The amount of light Lv at the center of the colored defect 3 of each color detected by the image pickup unit 2 was recorded.

When the detected colored defect 3 of each color is confirmed on the inspection screen, the color can be discriminated when the light intensity Lv at the center of the colored defect 3 is between 20/256 Lv and 240/256 Lv. Therefore, the ratio of the specular reflection illumination 22 to the scattered reflection illumination 23 for each inspected object 14 is changed from 10: 0 to 0:10 to detect the colored defect 3, and the effective range from 20/256 Lv to 240/256 Lv is set. confirmed.
In the embodiment, an 8-bit camera is used, but a 10-bit or 12-bit camera may be used. 7.8% to 93.8% of the camera output is in the range where color can be discriminated. For example, it ranges from 80/1024 Lv to 960/1024 Lv for a 10-bit camera and 320/4096 Lv to 3840/4096 Lv for a 12-bit camera.

Further, as a result of detecting the colored defects 3 of the red defect 31, the green defect 32, and the blue defect 33, even if the ratio of the normal reflection illumination 22 and the scattered reflection illumination 23 is changed and detected, the amount of light in the central portion of the colored defect 3 is detected. Lv had a relationship of red defect 31> green defect 32> blue defect 33. Therefore, the determination of 20/256 Lv was performed by the blue defect 33, and the determination of 240/256 Lv was performed by the red defect 31. At this time, the determination was calculated from the approximate expression. In the approximate expression, y is the defect light amount Lv, and x is the ratio of the illumination unit for scattering reflection. Thereby, each color defect of red, green, and blue can be discriminated within the effective range of the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23.

FIG. 9A is a diagram showing the relationship between the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 and the defective light amount Lv when the object 14 to be inspected is an iron plate (glossiness: 0.5). ..
It was confirmed that in this iron plate (glossiness: 0.5), all the defects were contained in the range of 20 Lv to 240 Lv of the light amount in the central part of the colored defect 3 regardless of the light receiving amount ratio. The effective range of the light receiving amount ratio is from 10:00 to 0:10.

FIG. 9B is a diagram showing the relationship between the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 and the defective light amount Lv when the object 14 to be inspected is a zinc-plated iron plate (glossiness: 0.9). Is. The approximate expression of the red defect 31 is y = 7.222x + 17.289, and the approximate expression of the blue defect 33 is y = 4.6236x + 14.809.
In this zinc-drawn iron plate (glossiness: 0.9), when the light receiving amount ratio is 8.875: 1.125, the blue defect 33 becomes 20 Lv or more. Further, even if the light receiving amount ratio is 0:10, it is 240 Lv or less. The effective range of the light receiving amount ratio is 8.875: 1.125 to 0:10.

FIG. 9C is a diagram showing the relationship between the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 and the defective light amount Lv when the object 14 to be inspected is a phosphorus bronze plate (glossiness: 5.7). Is. Further, the approximate expression of the red defect 31 ^{y = -2.537x 2 + 49.919x + 9.1701} , the approximate expression of the blue defect 33 is ^{y = -1.6204x 2 + 39.845x + 2.6514} .
In this phosphor bronze plate (glossiness: 5.7), when the light receiving amount ratio is 9.576: 0.424, the blue defect 33 becomes 20 Lv or more. Further, when the light receiving amount ratio is 2.575: 7.425, the red defect 31 becomes 240 Lv or less. The effective range of the light receiving amount ratio is 9.576: 0.424 to 2.575: 7.425.

FIG. 9D is a diagram showing the relationship between the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 and the defective light amount Lv when the object 14 to be inspected is an aluminum plate (glossiness: 10.2). be. The approximate expression of the red defect 31 is y = -4.7357 x ² + 69.288x + 18.311, and the approximate expression of the blue defect 33 is y = -3.1384 x ² + 55.997x + 1.7292.
In this aluminum plate (glossiness: 10.2), when the light receiving amount ratio is 9.667: 0.333, the blue defect 33 becomes 20 Lv or more. Further, when the light receiving amount ratio is 5.275: 4.725, the red defect 31 becomes 240 Lv or less. The effective range of the light receiving amount ratio is 9.667: 0.333 to 5.275: 4.725.

FIG. 9E is a diagram showing the relationship between the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 and the defective light amount Lv when the object 14 to be inspected is a copper plate (glossiness: 11.4). .. The approximate expression of the red defect 31 is y = -4.3927 x ² + 66.093 x + 19.57, and the approximate expression of the blue defect 33 is y = -3.066 x ² + 54.538 x + 4.3454.
In this copper plate (glossiness: 11.4), when the light receiving amount ratio is 9.707: 0.293, the blue defect 33 becomes 20 Lv or more. Further, when the light receiving amount ratio is 5.013: 4.987, the red defect 31 becomes 240 Lv or less. The effective range of the light receiving amount ratio is 9.707: 0.293 to 5.013: 4.987.

FIG. 9F is a diagram showing the relationship between the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 and the defective light amount Lv when the object 14 to be inspected is a stainless steel plate (glossiness: 23.6). be. Further, the approximate expression of the red defect 31 ^{y = 0.0313x 5 -1.049x 4 + 13.464x} 3 -81.864x 2 + 232.52x + 12.91, approximate expression of the blue defect 33 y = -0.0288x ⁵ +0 .6131x is a ^{4 -3.052x 3 -12.642x 2 + 131.34x +} 8.4542.
In this stainless steel plate (glossiness: 23.6), when the light receiving amount ratio is 9.911: 0.089, the blue defect 33 becomes 20 Lv or more. Further, when the light receiving amount ratio is 8.071: 1.929, the red defect 31 becomes 240 Lv or less. The effective range of the light receiving amount ratio is 9.911: 0.089 to 8.071: 1.929.

FIG. 10 is a diagram showing the relationship between the glossiness and the light receiving amount ratio of the light receiving amount from the specular reflection lighting 22 and the scattered reflection lighting 23. y ₁ = 10.638e ^−0.072x is an approximate expression of the upper limit value at which the defective light amount is 240 Lv or less, and y ₂ = 0.9898e ^−0.105x is an approximate expression of the lower limit value at which the defective light amount is 20 Lv or more. The plot with the name of the inspected object 14 shown in FIG. 10 shows the upper limit value and the lower limit value in the effective range of the light receiving amount ratio in each inspected object 14 described with reference to FIGS. 9A to 9B. .. The approximate expression of the upper limit value and the approximate expression of the lower limit value are the expressions obtained based on the plot.
From the above, the defect detection unit 11 has a specular reflection illumination 22 and a range in which the light receiving amount ratio y within the range of _{y 1} >y> y _{2 and both the specular reflection illumination 22 and the diffuse reflection illumination 23 are lit.} The output of the diffuse reflection illumination 23 is adjusted. As a result, the defect detection unit 11 can detect the colored defect 3 so that a person can discriminate the color of the defect of the RGB3 primary color on the screen. In practice, in order to facilitate the calculation, the light receiving amount ratio is set at the center position of _{y 1} = 10.638e ^−0.072x and y ₂ = 0.9898e ^−0.105x.
For example, the defect detection unit 11 determines the glossiness x (x = A ÷ B) of the inspected object 14 from the light receiving amount A from the specular reflection illumination 22 and the light receiving amount B from the diffuse reflection illumination 23 measured at the start of the inspection. calculate. The defect detection unit 11 calculates an upper limit value y ₁ (y ₁ = 10.638e ^−0.072x ) and a lower limit value y ₂ (y ₂ = 0.9898e −0.105x) based on the calculated ^{glossiness x.} do. The defect detection unit 11 calculates the ratio of the amount of light received from the diffuse reflection illumination 23 by y = (y ₁ + y ₂ ) / 2, and calculates the ratio of the amount of light received from the specular reflection illumination 22 by γ = 10 −y. Therefore, an appropriate light receiving amount ratio can be determined.

However, if the type of illumination changes, the ratio of the amount of light received from the specular reflection illumination 22 and the diffuse reflection illumination 23 changes, so that the calculated glossiness value also changes. Therefore, it is necessary to acquire the numerical value of the glossiness after selecting the specular reflection illumination 22 and the scattered reflection illumination 23. For example, when the specular reflection illumination 22 and the scattering reflection illumination 23 are selected, the No. 14 of the inspected object 14 is selected. 3: The glossiness of the phosphor bronze plate (JIS C5911) is measured.

Here, with reference to FIG. 11, No. 3: The glossiness of another inspected object 14 when the glossiness of the phosphor bronze plate (JIS C5911) is "1.00" will be described. FIG. 11 shows No. 3: It is a table showing the glossiness of another inspected object 14 when the glossiness of the phosphor bronze plate (JIS C5911) is "1.00". FIG. 11 shows No. of the object to be inspected 14, the glossiness of the object to be inspected 14, the glossiness in the examples, and the glossiness when the glossiness of the phosphor bronze plate is “1.00”.

As shown in FIG. 11, No. The glossiness of the iron plate of No. 1 is 0.5, and the glossiness of the phosphor bronze plate is 0.09 when the glossiness is "1.00". No. The glossiness of the zinc-coated iron plate of No. 2 is 0.9, and the glossiness of the phosphor bronze plate is 0.15 when the glossiness is "1.00". No. The glossiness of the phosphor bronze plate 3 in the embodiment is 5.7, and the glossiness when the phosphor bronze plate has a glossiness of "1.00" is 1.00. No. The glossiness of the aluminum plate of No. 4 in the embodiment is 10.2, and the glossiness of the phosphor bronze plate is 1.79 when the glossiness is "1.00". No. The glossiness of the copper plate of No. 5 is 11.4, and the glossiness of the phosphor bronze plate is 1.99 when the glossiness is "1.00". No. The glossiness of the stainless steel plate of No. 6 is 23.6, and the glossiness of the phosphor bronze plate is 4.14 when the glossiness is “1.00”.

FIG. 12 shows No. 3: The figure showing the relationship between the glossiness when the glossiness of the phosphorus bronze plate (JIS C5911) is "1.00" and the light receiving amount ratio of the light receiving amount from the effective specular reflection illumination 22 and the diffuse reflection illumination 23. be. No. 3: When the glossiness of the phosphorus bronze plate (JIS C5911) is "1.00", y = 10.638e ^−0.412x is an approximate expression in which the defect light amount is 240 Lv or less, and y = 0.9898e − ^{0. .602x} is an approximate expression in which the defect light amount is 20 Lv or more.

From the above, the light receiving amount ratio can be determined from the equations of _{y 1} = 10.638e ^−δx and y ₂ = 0.9898e ^−φx. At this time, δ and φ depend on the reference object 14 to be inspected. For example, No. 3: When the phosphor bronze plate (JIS C5911) is used as a reference, δ = 0.4105x ^−0.996 and φ = 0.6021x ^−1.001 .

Here, with reference to FIG. 13, No. 3: Phosphor bronze plate (JIS C5911) The δ value and φ value due to the numerical fluctuation of the glossiness will be described. FIG. 13 shows No. 3: It is a table which shows the δ value and φ value according to the numerical fluctuation of the glossiness of a phosphor bronze plate (JIS C5191). FIG. 13 shows the glossiness, the δ value, and the φ value.

As shown in FIG. 13, when the glossiness is 1, the δ value is 0.412 and the φ value is 0.602. When the glossiness is 2, the δ value is 0.206 and the φ value is 0.301. When the glossiness is 3, the δ value is 0.137 and the φ value is 0.201. When the glossiness is 4, the δ value is 0.103 and the φ value is 0.150. When the glossiness is 5, the δ value is 0.082 and the φ value is 0.120. When the glossiness is 6, the δ value is 0.069 and the φ value is 0.100. When the glossiness is 7, the δ value is 0.059 and the φ value is 0.086. When the glossiness is 8, the δ value is 0.052 and the φ value is 0.075. When the glossiness is 9, the δ value is 0.046 and the φ value is 0.067. When the glossiness is 10, the δ value is 0.041 and the φ value is 0.060.

The inspection of the object 14 to be inspected is carried out based on the total light receiving amount z of the light receiving amount a from the specular reflection illumination 22 and the light receiving amount b from the scattered reflection illumination 23. The light receiving amount a, the light receiving amount b, and the total light receiving amount z are calculated by the defect detection unit 11. The defect detection unit 11 calculates the light receiving amount a from the equation _{a = (10−y) / 10 × z 0.} The defect detection unit 11 calculates the light receiving amount b from the equation _{of b = y / 10 × z 0.} The defect detection unit 11 calculates the total received light amount z from the equation of z = a + b.
The defect detection unit 11 determines the specular reflection illumination 22 or the diffuse reflection illumination 23 so that the total light reception amount z, which is the sum of the calculated light reception amount a and the light reception amount b, is the total light reception amount z in the line type color sensor 21. Dimming at least one of the above. The light receiving amount z ₀ can be set according to the inspection conditions.

At this time, the dimming of the specular reflection illumination 22 and the scattering reflection illumination 23 needs to be performed alternately. There are multiple methods for dimming each light.
(Method 1)
With the object 14 to be inspected placed, the scattered reflection illumination 23 is turned off, and dimming is performed so that the amount of light received by the specular reflection illumination 22 is the amount of light received a. After dimming the specular reflection illumination 22, the specular reflection illumination 22 is turned off, and dimming is performed so that the amount of light received by the scattered reflection illumination 23 is the amount of light received b. After dimming the diffuse reflection illumination 23, the specular reflection illumination 22 is turned on and the inspection is started.
(Method 2)
The diffuse reflection illumination 23 is turned off, and the specular reflection illumination 22 is dimmed to the light receiving amount a. After dimming the specular reflection illumination 22, the diffuse reflection illumination 23 is turned on, and the diffuse reflection illumination 23 is dimmed to the light receiving amount z ₀ .
In the above-mentioned two dimming methods, the diffuse reflection illumination 23 may be the first in the order of dimming each illumination.

Next, the oil defect (brown) adhering to the copper plate (glossiness: 11.4) was inspected by the imaging unit 2. In the same manner as described above, the light receiving amount ratio between the light receiving amount a from the specular reflection illumination 22 and the light receiving amount b from the diffuse reflection illumination 23 was varied and detected.

Here, with reference to FIG. 14, the discriminant result of the inspection result of the oil defect (brown) adhering to the copper plate (glossiness: 11.4) will be described. FIG. 14 is a table showing inspection results for each light receiving amount ratio of oil defects adhering to the copper plate. FIG. 14 shows the light receiving amount ratio, the total light receiving amount, the defect light amount Lv, the defect detection result, and the defect color discrimination result. The defective light amount Lv indicates the defective light amount Lv of the oil defect (brown) with respect to the light receiving amount ratio of the light receiving amount a and the light receiving amount b. The total received light amount z is 128 Lv for all the received light amounts.

As shown in FIG. 14, when the light receiving amount ratio is 10: 0, the defect light amount Lv is 17.3 Lv, and the defect can be detected but the defect color cannot be discriminated. When the light receiving amount ratio is 9: 1, the defect light amount Lv is 59.6 Lv, and defect detection and defect color discrimination are possible. When the light receiving amount ratio is 8: 2, the defect light amount Lv is 157.0 Lv, and defect detection and defect color discrimination are possible. When the light receiving amount ratio is 7: 3, the defect light amount Lv is 182.5 Lv, and defect detection and defect color discrimination are possible. When the light receiving amount ratio is 6: 4, the defect light amount Lv is 226.7 Lv, and defect detection and defect color discrimination are possible. When the light receiving amount ratio is 5: 5, the defect light amount Lv is 241.7 Lv, and the defect can be detected but the defect color cannot be discriminated. When the light receiving amount ratio is 4: 6, the defect light amount Lv is 247.2 Lv, and the defect can be detected but the defect color cannot be discriminated. When the light receiving amount ratio is 3: 7, the defect light amount Lv is 253.0 Lv, and the defect can be detected but the defect color cannot be discriminated. When the light receiving amount ratio is 2: 8, the defect light amount Lv is 254.5 Lv, and the defect can be detected but the defect color cannot be discriminated. When the light receiving amount ratio is 1: 9, the defect light amount Lv is 254.9 Lv, and the defect can be detected but the defect color cannot be discriminated. When the light receiving amount ratio is 0:10, the defect light amount Lv is 254.7 Lv, and the defect can be detected but the defect color cannot be discriminated.

From the results shown in FIG. 14, the color discrimination of the oil defect (brown) is possible within the effective range of the light receiving amount ratio of the copper plate (see FIG. 9E) of 9.707: 0.293 to 5.013: 4.987. Met.
The center of the effective range of the light receiving amount ratio is 7.36: 2.64. Since the result of this time is between the result of 8: 2 and 7: 3, it was confirmed that there is no practical problem in dimming at the center of the effective range of the light receiving amount ratio.

With reference to FIGS. 15A and 15B, the waveform of the oil defect when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 10: 0 will be described. The vertical axis in FIGS. 15A and 15B shows the camera output, and the horizontal axis shows the camera pixels.
FIG. 15A is a diagram showing a waveform obtained by averaging the outputs of each color of the line type color sensor 21 when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 10: 0. From this waveform, it can be confirmed that the color of the defect has contrast and can be detected. However, the defect light amount Lv is 20 Lv or less. Therefore, it is impossible for a person to discriminate the defect color on the screen.
FIG. 15B is a diagram showing an output waveform of each color of the line type color sensor 21 when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 10: 0. The numerical values of the defect light amount Lv near the defect center were 19 Lv for the red output, 17 Lv for the green output, and 16 Lv for the blue output. From the output values of each of these colors, it can be seen that the color of the detected defect cannot be discriminated.

With reference to FIGS. 16A and 16B, the waveform of the oil defect when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 8: 2 will be described. The vertical axis in FIGS. 16A and 16B shows the camera output, and the horizontal axis shows the camera pixels.
FIG. 16A is a diagram showing a waveform obtained by averaging the outputs of each color of the line type color sensor 21 when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 8: 2. From this waveform, it can be confirmed that the color of the defect has contrast and can be detected. Further, the defect light amount Lv is between 20/256 Lv and 240/256 Lv. Therefore, it is possible for a person to discriminate the defect color on the screen.
FIG. 16B is a diagram showing an output waveform of each color of the line type color sensor 21 when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 8: 2. The numerical values of the defect light amount Lv near the defect center were 248 Lv for the red output, 133 Lv for the green output, and 90 Lv for the blue output. From the output values of each of these colors, it is possible to determine that the detected defect is brown.

With reference to FIGS. 17A and 17B, the waveform of the oil defect when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 3: 7 will be described. The vertical axis in FIGS. 17A and 17B shows the camera output, and the horizontal axis shows the camera pixels.
FIG. 17A is a diagram showing a waveform obtained by averaging the outputs of each color of the line type color sensor 21 when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 3: 7. From this waveform, it can be confirmed that the color of the defect has contrast and can be detected. However, the defect light amount Lv is 240 Lv or more. Therefore, it is impossible for a person to discriminate the defect color on the screen.
FIG. 17B is a diagram showing an output waveform of each color of the line type color sensor 21 when the light receiving amount ratio of the light receiving amount from the specular reflection illumination 22 and the diffuse reflection illumination 23 is 3: 7. The numerical values of the defect light amount Lv near the defect center were 255 Lv for the red output, 255 Lv for the green output, and 249 Lv for the blue output. From the output values of each of these colors, it can be seen that the color of the detected defect cannot be discriminated.

Regardless of the ratio of the amount of light received from the specular illumination 22 and the diffuse reflection illumination 23, the red output is 150 Lv, the green output is 125 Lv, and the blue output is 110 Lv in the normal part of the object 14 to be inspected. It can be determined that it is dark brown. In the present invention, it is possible to detect the colored defect 3 and distinguish the color of the colored defect 3 and the inspected object 14 by controlling the light receiving amount ratio of the light received from the specular reflection illumination 22 and the diffuse reflection illumination 23. I understand.

The embodiment of the present invention has been described above.
As described above, in the defect inspection device 1 of the present invention, the specular reflection illumination 22 irradiates the object 14 to be inspected with the first specularly reflected light at an irradiation angle θ. The diffuse reflection illumination 23 irradiates the position where the first light is irradiated with the second light scattered and reflected at an irradiation angle α different from the irradiation angle θ. The line type color sensor 21 receives the reflected light of the first light and the reflected light of the second light.
The defect detection unit 11 has a glossiness x (x = A) of the object to be inspected 14 based on the light receiving amount A of the reflected light of the first light and the light receiving amount B of the reflected light of the second light in the line type color sensor 21. ÷ B) is calculated. Defect detecting section 11 calculates a discernible amount of received light ratio upper limit value y ₁ and the lower limit value y ₂ and y color defects RGB3 primary for gloss x the calculated inspection object 14. The defect detection unit 11 determines the light receiving amount a of the first light reflected by the line type color sensor 21 and the reflected light of the second light based on the light receiving amount ratio y within the range of _{y 1} >y> y _2. The light receiving amount b is calculated. The defect detection unit 11 dims at least one of the specular reflection illumination 22 and the scattered reflection illumination 23 so that the sum of the calculated light reception amount a and the light reception amount b is the total light reception amount in the line type color sensor 21. I do.

With this configuration, the defect inspection device 1 of the present invention displays on the screen the total light-receiving amount of the light-receiving amount a and the light-receiving amount b in the line-type color sensor 21 according to the glossiness x of the object 14 to be inspected. The material state of the inspection object 14 is controlled within an effective range that can be discriminated by a person. Thereby, the person can discriminate the material state such as the color of the colored defect and the color of the inspected object in the inspected object displayed on the screen.

Therefore, the defect inspection device 1 of the present invention makes it possible for a person to discriminate the material state such as the color of the colored defect in the inspected object displayed on the screen and the color of the inspected object.

The defect inspection device 1 in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by a computer system and executed. The term "computer system" as used herein includes hardware such as an OS and peripheral devices. Further, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, or a CD-ROM, and a storage device such as a hard disk built in a computer system. Further, a "computer-readable recording medium" is a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line, and dynamically holds the program for a short period of time. It may also include a program that holds a program for a certain period of time, such as a volatile memory inside a computer system that is a server or a client in that case. Further, the above program may be for realizing a part of the above-mentioned functions, and may be further realized for realizing the above-mentioned functions in combination with a program already recorded in the computer system. It may be realized by using a programmable logic device such as FPGA (Field Programmable Gate Array).

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and includes designs and the like within a range that does not deviate from the gist of the present invention.

1 ... Defect inspection device 11 ... Defect detection unit 12 ... Rotary encoder 13 ... Operation unit 14 ... Object to be inspected 2 ... Imaging unit 21 ... Line type color sensor 22 ... Specular reflection lighting 23 ... Scattered reflection lighting 24 ... Normal 3 ... Colored Defect 31 ... Red defect 32 ... Green defect 33 ... Blue defect

Claims (3)

The first illumination that irradiates the object to be inspected with the first light at the irradiation angle θ, and
A second illumination that irradiates the second light at an irradiation angle α different from the irradiation angle θ with respect to the position where the first light is irradiated, and
The first reflected light generated by positive reflection of the first light irradiated on the object to be inspected and the second light generated by scattered reflection of the second light irradiated on the object to be inspected. A line-type color sensor that receives the reflected light of 2 and
The glossiness x (x = A ÷ B) of the object to be inspected is calculated based on the received amount A of the reflected light of the first light and the received amount B of the reflected light of the second light in the line type color sensor. _{Then, the upper limit value y 1} and the lower limit value y ₂ of the light receiving amount ratio y capable of discriminating the color of the defect of the RGB3 primary color with respect to the glossiness x of the inspected object are calculated, and within the range of _{y 1} >y> y _2. Based on the light reception amount ratio y, the light reception amount a of the reflected light of the first light and the light reception amount b of the reflected light of the second light in the line type color sensor are calculated, and the light reception amount a and the light reception amount b. A defect detection unit that adjusts at least one of the first illumination and the second illumination so that the sum of the light is the total amount of light received in the line type color sensor.
Defect inspection equipment with. The irradiation angle θ is an angle formed by the first light irradiated to the object to be inspected and the normal at the position where the first light is irradiated to the object to be inspected.
The irradiation angle α is an angle formed by the second light applied to the object to be inspected and the normal line.
The light receiving angle θ of the reflected light of the first light received by the line type color sensor is an angle formed by the reflected light of the first light and the normal line.
When the light receiving angle θ is −θ degree and the irradiation angle θ is + θ degree with respect to the normal line,
In the second illumination, the irradiation angle α is an angle within the range of −90 degrees <α <−θ degrees, an angle within the range of −θ degrees <α <+ θ degrees, or + θ degrees <α <+ 90 degrees. Provided so that the angle is within the range,
The defect inspection apparatus according to claim 1. The first illumination irradiates the object to be inspected with the first light at an irradiation angle θ.
The second illumination irradiates the second light with respect to the position where the first light is irradiated at an irradiation angle α different from the irradiation angle θ.
The line-type color sensor scatters the reflected light of the first light generated by the positive reflection of the first light irradiated on the object to be inspected and the second light irradiated on the object to be inspected. Receiving the reflected light of the second light generated by reflection and
The defect detecting unit determines the glossiness x (x = A) of the object to be inspected based on the received amount A of the reflected light of the first light and the received amount B of the reflected light of the second light in the line type color sensor. _{÷ B) is calculated, and the upper limit value y 1} and the lower limit value y ₂ of the light receiving amount ratio y that can discriminate the color of the defect of the RGB3 primary color with respect to the glossiness x of the inspected object are calculated, and y ₁ >y> y. _{Based on the light receiving amount ratio y within the range of 2} , the light receiving amount a of the reflected light of the first light and the light receiving amount b of the reflected light of the second light in the line type color sensor are calculated, and the light receiving amount a. Dimming of at least one of the first illumination and the second illumination is performed so that the sum of the light receiving amount b and the light receiving amount b is the total light receiving amount in the line type color sensor.
Defect inspection methods including.

Images