JPH09218094A - Color unevenness inspection device - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To obtain subtle color unevenness by obtaining color image data with good reproducibility according to the type of inspection object. An image pickup angle of a color camera 3 with respect to a glass substrate 1 is controlled by controlling an angle of a θ moving table 11, and red, green, and blue of color image data at these image pickup angles are represented by a Munsell table. The image data is converted into image data of at least hue of the color system, and the imaging angle in the histogram having the largest difference between the maximum value and the minimum value of each histogram of the image data of this hue is set as the optimum angle.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color unevenness inspection apparatus for inspecting subtle color unevenness of an inspection object such as an alignment film or a coating plate applied to a glass substrate of a liquid crystal display.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram of such a color unevenness inspection apparatus. A glass substrate 1 of a liquid crystal display is arranged as an inspection object, and an illuminating device 2 is arranged diagonally above the glass substrate 1.

The glass substrate 1 on the side opposite to the lighting device 2
Above the above is an industrial color television camera (hereinafter,
3 is arranged. The color camera 3 captures an image of the entire inspection area of the glass substrate 1 illuminated by the illumination device 2 from diagonally above the glass substrate 1 and outputs a video signal thereof. This video signal is digitally converted and input to the image processing unit 4.

The reason why the image is picked up obliquely from above the glass substrate 1 is that the color unevenness of the glass substrate 1 is subtle and it is difficult to recognize the color unevenness from directly above. .

The image processing unit 4 takes in a digital video signal and stores it as color image data, and determines the uneven color portion on the glass substrate 1 from the gray level of this color image data. The determination result of the uneven color portion on the glass substrate 1 is displayed on the monitor television 5.

[0006]

However, the appearance of the glass substrate 1 differs depending on the type of the glass substrate 1, that is, the color image data obtained by the image pickup of the color camera 3 depending on the type of the glass substrate 1. The contrast is different.

Therefore, it is necessary to adjust the image pickup angle of the color camera 3 with respect to the glass substrate 1 depending on the type of the glass substrate 1 so that the best contrast can be obtained.
However, in the above apparatus, the arrangement angle of the glass substrate 1 is fixed, and the image pickup angle is not set optimally depending on the type of the glass substrate 1, and it is not possible to obtain color image data with good reproducibility. It is difficult to determine color unevenness.

Therefore, according to the present invention, it is possible to obtain color image data having good reproducibility according to the kind of the inspection object,
An object of the present invention is to provide a color unevenness inspection device capable of determining subtle color unevenness.

[0009]

According to a first aspect of the present invention, there is provided a color unevenness inspection apparatus for inspecting color unevenness of an inspection object based on color image data obtained by imaging the inspection object with an imaging device. Angle control means for controlling a relative imaging angle of the device with respect to the inspection object, and red, green, and blue of each color image data obtained by imaging of the imaging device at a plurality of imaging angles controlled by the angle control means. Of at least one of hue, saturation, and lightness, and an imaging angle of an imaging device that images the inspection object based on the image data obtained by the conversion means. And an angle setting means for setting an optimum angle from among the above.

In such a color unevenness inspection apparatus, the image pickup angle of the image pickup apparatus with respect to the inspection object is controlled, and the image pickup apparatus takes an image of the inspection object with each image pickup angle. When the image of the inspection object is picked up by the image pickup device at these image pickup angles, the respective color image data are sent to the converting means, and the red, green, and blue of the color image data are at least hue and saturation image data by the converting means. Is converted to.

Then, each image data of these hues and saturations is sent to the angle setting means, where the image pickup angle of the image pickup device for picking up the inspection object is set to the optimum angle based on at least the image data of hue. .

According to a second aspect of the present invention, in the color unevenness inspection apparatus according to the first aspect, the conversion means obtains at least an image data of hues, and the angle setting means obtains each histogram of each image data of hues at each imaging angle. And the image pickup angle in the histogram having the largest difference between the maximum value and the minimum value of these histograms is set as the optimum angle.

According to a third aspect of the present invention, in the color unevenness inspection apparatus according to the first aspect, the conversion means obtains at least image data of hue and saturation, and the angle setting means sets the hue and saturation at each imaging angle. Vectors of these hues and saturations are created from each image data, and the imaging angle with the largest vector of these vectors is set as the optimum angle.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION

(1) Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a color unevenness inspection apparatus corresponding to claims 1 and 2. The glass substrate 1 of the liquid crystal display is placed on the θ moving table 11 of the angle adjusting mechanism 10. The angle adjusting mechanism 10 is provided with a θ-axis drive motor 13 on an upper part of a gantry 12, and a θ-moving table 11 is connected to a rotation shaft of the θ-axis drive motor 13.

Therefore, the θ moving table 11 is a mechanism that rotates in the θ direction with respect to the illumination device 2 in response to the drive of the θ axis drive motor 13. On the other hand, the determination processing unit 20
Has a function of determining a subtle color unevenness by setting an optimum imaging angle θ according to the type of glass substrate 1 based on the color image data of the glass substrate 1 captured by the color camera 3. .

Specifically, the main control unit 21 is provided, and the input unit 22, the output unit 23, the operation unit 24, and the image memory 25 are connected to the main control unit 21, and the main control unit 21 is also provided.
The RGB-HSI conversion unit 26, according to a command issued from
Each function as the angle setting unit 27, that is, the angle data table 28, the histogram creation unit 29, the maximum / minimum detection unit 30, the optimum angle determination unit 31, and the rotation control unit 3
2. The image processing unit 33 operates.

Of these, the input section 22 is connected to the output terminal of the color camera 3 and A / D (analog / digital) converts the video signal output from the color camera 3 to obtain an image memory as color image data. It has a function to send to 25.

The output section 23 has a monitor television 34.
Are connected to display the image data stored in the image memory 25 on the monitor television 34.
The operation unit 24 is, for example, a keyboard or a mouse.

The RGB-HSI converter 26 reads the color image data of the glass substrate 1 stored in the image memory 25, and R, G, B in this color image data is read.
Each of the color signals of H, H, S, and I of the Munsell color system
It has a function of converting into each image data.

Here, each image data of the hue H, the saturation S, and the brightness I converted by the RGB-HSI converter 26 is as follows.
Since the contrast is low, RG
R of the color image data by the B-HSI conversion unit 26,
The conversion processing from G and B to the image data of the hue H, the saturation S, and the lightness I of the Munsell color system is repeated, and these conversion data are sequentially added to each other to enhance the image.
You may make it obtain each image data of saturation Sn and brightness In.

The angle data table 28 stores in advance the angle θ of the θ moving table 11 with respect to the illuminating device 2, that is, the image pickup angle for adjustment of the glass substrate 1 of the color camera 3, for example, θ, θ + Δθ, θ + 2Δθ.

The histogram creating section 29 is used for the image memory 2
Of the image data of the hue Hn, the saturation Sn, and the lightness In stored in FIG. 5, for example, the image data of the hue Hn is read out, and the function of creating a histogram of the number of pixels with respect to the hue value in the image data of the hue Hn is created. Have

The histogram creating unit 29 has a function of creating a histogram for each image data of each hue Hn for each image pickup angle θ, θ + Δθ, and θ + 2Δθ of the color camera 3 with respect to the glass substrate 1. ing.

The maximum / minimum detecting section 30 has a function of detecting the maximum value hmax and the minimum value hmin of the hue value in each histogram for each of the image pickup angles θ, θ + Δθ, and θ + 2Δθ for adjustment.

The optimum angle determination unit 31 is for the respective image pickup angles θ, θ + Δθ, θ + 2 obtained by the maximum / minimum detection unit 30.
Each difference value of the maximum value hmax and the minimum value hmin of the hue value for each Δθ Difference value = hmax−hmin (1) is obtained, and the imaging angle θ indicating the maximum value of the difference value,
It has a function of determining θ + Δθ or θ + 2Δθ as the optimum imaging angle.

The hue H is used because the width of the hue circle is widened when the contrast is high, so that the point where the width of the hue circle is widest is set as the optimum angle. The rotation control unit 32 drives the θ-axis drive motor 13 to control the rotation of the θ movement table 11 in the θ direction, receives the optimum image capturing angle determined by the optimum angle determining unit 31, and receives the optimum image capturing angle. It has a function of controlling the rotation of the θ movement table 11 at an angle.

The image processing section 33 has a function of reading the color image data stored in the image memory 25 and determining the color unevenness portion on the glass substrate 1 from the gray level of this color image data.

The image processing unit 33 also includes an adding unit 26a.
At least one of image data of hue Hn, saturation Sn, and lightness In obtained by
Of the image data of the hue Hn, a histogram of the frequency with respect to the gray level of the image data of the hue Hn is created, and then the average value and the variance value are calculated from the histogram result, and the average value and the variance value are the first predetermined values. It is determined whether or not it is within the range, and if the average value and the variance value are outside the first allowable range, the image data of the hue Hn is divided into quarters to create each area image data, A function to repeat the process of creating a histogram of the frequency of these area image data against the gray level and calculating the average value and variance of the histogram, and determining the presence or absence of color unevenness in the finally obtained area image data. have.

Next, the operation of the apparatus configured as described above will be described. The main controller 21 uses the angle data table 2
Imaging angles θ, θ + Δθ, θ + 2Δ stored in
θ is read and sequentially passed to the rotation control unit 32.

The rotation control unit 32 sequentially receives the image pickup angles θ, θ + Δθ, and θ + 2Δθ, and first receives the image pickup angle θ.
The θ-axis driving motor 13 is driven so that the angle θ of the θ-moving table 11 with respect to the lighting device 2 is set.

At this time, the color camera 3 picks up an image of the glass substrate 1 illuminated by the illumination device 2 and outputs the image signal. This video signal is sent to the input unit 22 of the determination processing device 20, where it is converted into a digital video signal,
It is stored in the image memory 25 as color image data when the imaging angle is θ.

Next, the rotation control unit 32 determines the image pickup angle θ + Δ.
The θ-axis drive motor 13 is sequentially driven so as to obtain θ and θ + 2Δθ, whereby the θ movement table 11 is sequentially set to the illumination device 2 at angles θ + Δθ and θ + 2Δθ.

At this time, the color camera 3 picks up an image of the glass substrate 1 illuminated by the illumination device 2 and outputs a video signal thereof. This video signal is sent to the input unit 22 of the determination processing device 20, where it is converted into a digital video signal,
The image data is sequentially stored in the image memory 25 as each color image data when the imaging angles are θ + Δθ and θ + 2Δθ.

In this way, each imaging angle θ, θ + Δθ, θ +
When each color image data of 2Δθ is stored in the image memory 25, the RGB-HSI conversion unit 26 causes the image memory 25 to
Imaging angles θ, θ + Δθ, θ + 2Δθ stored in
In the image memory 25, the R, G, and B color signals in the color image data are sequentially read out and converted into the Munsell color system hue H, saturation S, and lightness I image data. Remember.

Here, as described above, since the image data of the hue H, the saturation S, and the brightness I converted by the RGB-HSI conversion unit 26 has a low contrast, the image enhancement of FIG. Flowchart step # 1
As shown in # 4, the RGB-HSI conversion unit 26 repeats the conversion processing from R, G, B of the color image data to each image data of the hue H, the saturation S, and the lightness I of the Munsell color system, These pieces of conversion data are sequentially added to obtain image data of hue Hn, saturation Sn, and brightness In that emphasizes the image.

Next, the histogram creating section 29 determines the hue Hn, the saturation Sn, and the brightness In stored in the image memory 25.
For example, the image data of the hue Hn is read out for each imaging angle θ, θ + Δθ, and θ + 2Δθ, and a histogram of the number of pixels with respect to the hue value of each image data of the hue Hn is created.

FIGS. 3A, 3B and 3C show the results of creating a histogram of the number of pixels with respect to such hue values. FIG. 3A shows the histogram at the imaging angle θ, and FIG. 3B shows the imaging. Angle θ +
Histogram when Δθ, Figure (c) shows imaging angle θ + 2
It is a histogram when Δθ.

Next, the maximum / minimum detecting section 30 detects the maximum value hmax and the minimum value hmin of the hue value in each histogram for each of these imaging angles θ, θ + Δθ, θ + 2Δθ.

For example, in the histogram at the image pickup angle θ shown in FIG. 3 (a), the maximum value hmax1 and the minimum value hmi of the hue values are shown.
Detecting n1 and using the histogram at the imaging angle θ + Δθ shown in Fig. 6 (b), the maximum hue value hmax2 and minimum hue value hmin2
Is detected, and in the histogram at the imaging angle θ + 2Δθ shown in FIG. 7C, the maximum hue value hmax3 and the minimum hue value hmin3
Is detected.

Next, the optimum angle determination unit 31 determines the respective imaging angles θ, θ + Δθ, θ obtained by the maximum / minimum detection unit 30.
The difference between the maximum value hmax and the minimum value hmin of the hue value for each + 2Δθ is calculated according to the above equation (1), and the image pickup angle θ, θ + Δθ or θ + 2Δθ showing the largest difference value is determined as the optimum image pickup angle. .

That is, each imaging angle θ, θ + Δθ, θ +
In the case of 2Δθ, the relationship between the maximum value hmax and the minimum value hmin of the hue values is (hmax1−hmin1) <(hmax2−hmin2)> (hmax3−hmin3) (2).

Therefore, the optimum angle determination unit 31 determines the difference value h
Since max2−hmin2 is the largest value, the imaging angle θ
When it is + Δθ, it is determined that the contrast has the highest imaging angle, and this imaging angle θ + Δθ is sent to the rotation control unit 32.

The rotation control unit 32 determines the optimum image pickup angle θ.
+ Δθ is received, so that the imaging angle becomes θ + Δθ
The rotation of the moving table 11 is controlled. When the optimum imaging angle θ + Δθ corresponding to the type of glass substrate 1 is set in this way, the color camera 3 images the glass substrate 1 illuminated by the illumination device 2 and outputs the video signal. This video signal is converted into a digital video signal by the input unit 22 and stored in the image memory 25 as color image data at the optimum imaging angle θ + Δθ.

Next, the image processing section 33 reads the color image data stored in the image memory 25, and determines the uneven color portion on the glass substrate 1 from the gray level of this color image data.

As another method for determining the color unevenness, RGB is used.
The −HSI conversion unit 26 sequentially reads the color image data at the imaging angle θ + Δθ stored in the image memory 25, and outputs the R, G, and B color signals in this color image data to the hue H and color of the Munsell color system. The image data is converted into image data of S and lightness I and stored in the image memory 25.

Here, the adder 26a uses the RGB-HSI.
The conversion processing of the color image data R, G, B from the Munsell color system hue H, the saturation S, and the lightness I by the conversion unit 26 is repeated, and these conversion data are sequentially added to each image. The respective image data of the hue Hn, the saturation Sn, and the lightness In that are emphasized are obtained.

The image processing unit 33 reads out at least one image data of the image data of the hue Hn, the saturation Sn, and the brightness In obtained by the adding unit 26a, for example, the image data of the hue Hn, and the image data of the hue Hn. Create a histogram of the frequency with respect to the gray level, and then calculate the average value and variance value from this histogram result, and determine whether these average value and variance value are within the first predetermined range. If the average value and the variance value are outside the first allowable range, the image data of the hue Hn is divided into quarters to create each area image data, and the histogram of the frequency with respect to the gray level of these area image data is again created. Is repeated and the average value and the variance value thereof are calculated, and the presence or absence of color unevenness is determined in the finally divided area image data.

As described above, in the first embodiment, the glass substrate 1 is imaged by controlling the image pickup angle of the color camera 3 with respect to the glass substrate 1, and the red, green, and blue of these color image data are displayed in the Munsell table. At least the hue of the color system is converted into image data, and the image pickup angle in the histogram having the largest difference between the maximum value and the minimum value of each histogram of this hue image data is set as the optimum angle. The image pickup angle of the color camera 1 with respect to the glass substrate 1 can be automatically adjusted to obtain the best contrast according to the type of product 1, color image data with good reproducibility can be obtained, and subtle color unevenness can be determined. it can. (2) Next, a second embodiment of the present invention will be described.
The same parts as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

FIG. 4 is a block diagram of a color unevenness inspection apparatus corresponding to the first and third aspects. This color unevenness inspection apparatus is applied especially when the color change in the glass substrate 1 is subtle.
The angle setting means 40 has the functions of an angle data table 41, a vector creation unit 42, and an optimum angle determination unit 43.

In the angle data table 41, similarly to the above, the angle θ of the θ movement table 11 with respect to the illumination device 2,
That is, the imaging angles for adjustment of the color camera 3 with respect to the glass substrate 1, for example, θ, θ + Δθ, and θ + 2Δθ are stored in advance.

The vector creating section 42 has the respective imaging angles θ, θ + Δθ, θ + obtained by the RGB-HSI converting section 26.
It has a function of creating a vector of the hue Hn and the saturation Sn from each image data of the hue Hn and the saturation Sn for each 2Δθ.

The optimum angle determination unit 43 has a function of setting the imaging angle θ, θ + Δθ or θ + 2Δθ of the largest vector among these vectors as the optimum angle. Next, the operation of the apparatus configured as described above will be described.

Similarly to the above, the rotation control unit 32 sequentially receives the respective image pickup angles θ, θ + Δθ, θ + 2Δθ, and first drives the θ-axis drive motor 13 so as to obtain the image pickup angle θ, thereby illuminating the θ movement table 11. The angle θ is set with respect to the device 2.

At this time, the color camera 3 takes an image of the glass substrate 1 illuminated by the illumination device 2 and outputs the image signal. This video signal is sent to the input unit 22 of the determination processing device 20, where it is converted into a digital video signal,
It is stored in the image memory 25 as color image data when the imaging angle is θ.

Next, the rotation controller 32 determines the image pickup angle θ + Δ.
The θ-axis drive motor 13 is sequentially driven so as to obtain θ and θ + 2Δθ, whereby the θ movement table 11 is sequentially set to the illumination device 2 at angles θ + Δθ and θ + 2Δθ.

Each time, the color camera 3 picks up an image of the glass substrate 1 illuminated by the illumination device 2 and outputs the image signal thereof. This video signal is sent to the input unit 22 of the determination processing device 20, where it is converted into a digital video signal,
The image data is sequentially stored in the image memory 25 as each color image data when the imaging angles are θ + Δθ and θ + 2Δθ.

In this way, each imaging angle θ, θ + Δθ, θ +
When each color image data of 2Δθ is stored in the image memory 25, the RGB-HSI conversion unit 26 causes the image memory 25 to
Imaging angles θ, θ + Δθ, θ + 2Δθ stored in
In the image memory 25, the R, G, and B color signals in the color image data are sequentially read out and converted into the Munsell color system hue H, saturation S, and lightness I image data. Remember.

Here, as described above, since the image data of the hue H, the saturation S, and the brightness I converted by the RGB-HSI conversion unit 26 has low contrast, the RGB-HSI conversion unit in the addition unit 26a. The conversion processing from R, G, and B of the color image data to the image data of the hue H, the saturation S, and the lightness I of the Munsell color system by 26 is repeated, and these conversion data are sequentially added to emphasize each image. Each image data of the hue Hn, the saturation Sn, and the brightness In obtained.

Next, the vector creating section 42 uses the image memory 2
Image pickup angles θ, θ + Δθ, θ + 2Δ stored in
Of the image data of the hue Hn, the saturation Sn, and the lightness I for each θ, the image data of the hue Hn and the saturation Sn are read out, and the vector of polar coordinates shown in FIG. 5 is obtained using the hue Hn and the saturation Sn. create.

This vector has the hue Hn as an angle and the color S as
It is created with n as the size. The vector creation unit 42
A vector is created for each pixel data of each image data of each imaging angle θ, θ + Δθ, θ + 2Δθ, and a maximum vector SHmax and a minimum vector SHmin of each image data of each imaging angle θ, θ + Δθ, θ + 2Δθ.
And ask.

That is, as shown in FIG. 6, the imaging angle θ
Maximum vector Shmax1 and minimum vector Shmin1
And the maximum vector Shma when the imaging angle θ + Δθ
x2, the minimum vector Shmin2, and the imaging angle θ + 2Δθ
In this case, the maximum vector Shmax3 and the minimum vector hmin3.

Then, the vector creating section 42 calculates the vector sum of the maximum vector SHmax and the minimum vector SHmin. That is, the vector sum S at the imaging angle θ
h1 and the vector sum Sh2 at the imaging angle θ + Δθ
And the vector sum Sh3 at the imaging angle θ + 2Δθ
Becomes

Next, the optimum angle determination unit 43 determines the largest vector sum of these vector sums Sh1, Sh2, Sh3, here the vector sum Sh2, and sets the imaging angle θ + Δθ corresponding to this vector sum Sh2 as the optimum angle. Set.

Therefore, the optimum angle determination unit 43 determines that the contrast is the highest at the imaging angle θ + Δθ, and sends the imaging angle θ + Δθ to the rotation control unit 32.

The rotation control unit 32 determines the optimum image pickup angle θ.
+ Δθ is received, so that the imaging angle becomes θ + Δθ
The rotation of the moving table 11 is controlled. When the optimum imaging angle θ + Δθ corresponding to the type of glass substrate 1 is set in this way, the color camera 3 images the glass substrate 1 illuminated by the illumination device 2 and outputs the video signal. This video signal is converted into a digital video signal by the input unit 22 and stored in the image memory 25 as color image data at the optimum imaging angle θ + Δθ.

Next, the image processing unit 33 reads the color image data stored in the image memory 25, and determines the uneven color portion on the glass substrate 1 from the gray level of this color image data.

As another method for determining color unevenness, similarly to the above, the RGB-HSI conversion unit 26 sequentially reads the color image data at the imaging angle θ + Δθ stored in the image memory 25, and the color image data R in
Hu and H of the Munsell color system, saturation S,
The image data having the lightness I is converted and stored in the image memory 25.

Here, the adder 26a uses the RGB-HSI.
The conversion processing of the color image data R, G, B from the Munsell color system hue H, the saturation S, and the lightness I by the conversion unit 26 is repeated, and these conversion data are sequentially added to each image. The respective image data of the hue Hn, the saturation Sn, and the lightness In that are emphasized are obtained.

The image processing unit 33 reads out at least one image data of the image data of the hue Hn, the saturation Sn, and the brightness In obtained by the adding unit 26a, for example, the image data of the hue Hn, and the image data of the hue Hn. Create a histogram of the frequency for the light and shade levels of, then calculate the average value, variance value from this histogram result, determine whether these average value, variance value is within a predetermined range, these average values, If the variance value is outside the allowable range, the image data of the hue Hn is divided into quarters to create each area image data, and again the histogram of the frequency with respect to the gray level of these area image data is created and the average thereof is created. The calculation of the value and the variance value is repeated, and the presence or absence of color unevenness is determined in the area image data finally obtained by division.

As described above, in the second embodiment, the vector of the hue Hn and the saturation Sn is created from each image data of the hue Hn and the saturation Sn at each imaging angle. Since the image pickup angle with the largest vector is set as the optimum angle, even if the glass substrate 1 has a slight color unevenness in color change, the image pickup angle of the color camera 1 with respect to the glass substrate 1 is set to the best contrast. Therefore, it is possible to obtain the color image data with good reproducibility and to judge the subtle color unevenness.

[0071]

As described in detail above, claims 1 to 5 of the present invention.
According to 3, it is possible to provide the color image data having good reproducibility according to the kind of the inspection object, and to provide the color unevenness inspection apparatus capable of determining the subtle color unevenness.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a color unevenness inspection device according to the present invention.

FIG. 2 is a flowchart of image enhancement.

FIG. 3 is a diagram showing a histogram of the number of pixels with respect to a hue value.

FIG. 4 is a configuration diagram showing a second embodiment of a color unevenness inspection apparatus according to the present invention.

FIG. 5 is a diagram showing a vector composed of hue and saturation.

FIG. 6 is a diagram showing each vector sum composed of hue and saturation.

FIG. 7 is a configuration diagram of a conventional color unevenness inspection device.

[Explanation of symbols]

1 ... Glass substrate, 2 ... Illumination device, 3 ... Color camera, 1
0 ... Angle adjusting mechanism, 11 ... θ moving table, 12 ... Stand, 13 ... θ axis drive motor, 20 ... Judgment processing unit, 21 ...
Main control unit, 25 ... Image memory, 26 ... RGB-HSI conversion unit, 27 ... Angle setting means, 28 ... Angle data table, 29 ... Histogram creation unit, 30 ... Maximum / minimum detection unit, 31 ... Optimal angle determination unit, 32 ... Rotation control unit, 33 ...
Image processing unit, 40 ... Angle setting means, 41 ... Angle data table, 42 ... Vector creation unit, 43 ... Optimal angle determination unit.

Claims (3)

[Claims] 1. A color unevenness inspection device for inspecting color unevenness of the inspection target based on color image data obtained by capturing an image of the inspection target with an imaging device, wherein the image pickup device is relative to the inspection target. Angle control means for controlling various image pickup angles, and red, green, and blue of the respective color image data obtained by the image pickup of the image pickup device at a plurality of image pickup angles controlled by the angle control means, hue, saturation, A conversion unit for converting at least one image data of brightness and an image pickup angle of the image pickup device for picking up an image of the inspection object based on the image data obtained by the conversion unit is optimum from the plurality of image pickup angles. An apparatus for inspecting color unevenness, comprising: an angle setting means for setting an angle. 2. The conversion means obtains image data of at least hue, the angle setting means obtains each histogram of each image data of hue at each imaging angle, and a difference value between the maximum value and the minimum value of these histograms. The color unevenness inspection apparatus according to claim 1, wherein the imaging angle in the histogram having the largest value is set as the optimum angle. 3. The conversion means obtains at least image data of hue and saturation, and the angle setting means creates vectors of these hue and saturation from each image data of hue and saturation at each imaging angle. Then, the color unevenness inspection apparatus according to claim 1, wherein the imaging angle of the largest vector among these vectors is set as the optimum angle.