TWI758609B - Image generation device and image generation method - Google Patents

Abstract

An objective of the present invention is generating an image required for accurate determination of defects in a display panel. A solution therefor includes: a mounting table 11 on which a display panel P is mounted; a camera 12 provided to face the display panel P; a calculation tool 171a which calculates the mean value of the luminance levels of the peripheral pixels of a target pixel based on the image data captured by the camera 12 as the mean value of the peripheral pixels; a defect determination tool 171b which determines that a defect is present in the image pickup pixel of the camera 12 corresponding to the target pixel if the differential between the luminance level of the target pixel and the calculated mean value of the peripheral pixels is greater than a set threshold; and a correction tool 171d which corrects the luminance level of the target pixel as the mean value of the peripheral pixels and stores the corrected image data to a memory 172 if the defect determination tool 171b determines that a defect is present in the image pickup pixel of the camera 12 corresponding to the target pixel.

Description

Image generation device and image generation method

The present invention relates to an image generating apparatus and an image generating method for generating an image required for inspection of a display panel.

Display panels such as liquid crystal display panels, organic electroluminescence (organic electroluminescence) display panels (hereinafter referred to as panels or display panels), display devices (such as monitors, personal computers, portable terminals (tablet terminals, smart Mobile phones, mobile phones, etc.), etc.), the appearance and lighting state of the display panel will be inspected during manufacture and before shipment. The inspection of the appearance and lighting state of the display panel has been carried out by the method of photographing the display panel as the object to be inspected by photographing means such as a camera, and performing inspection based on the captured image.

For example, Patent Document 1 discloses that the luminance of each pixel extracted as a candidate for a pixel having a bright spot defect is divided by the luminance of the pixel based on the luminance data of an image obtained by photographing a liquid crystal display panel with a CCD camera. The average value of the brightness of the surrounding eight adjacent pixels of the same color is obtained to obtain the contrast ratio, and then the sum of the calculated contrast ratios is corrected corresponding to the color information, and then the corrected defect contrast ratio is calculated. A technology to determine whether a pixel has a bright spot defect by comparing it with a preset determination threshold.

[Prior Art Literature] [Patent Literature]

(Patent Document 1) Japanese Patent Publication No. 2010-146733

However, as in the technique disclosed in Patent Document 1, when judging whether there is a bright spot defect based on the luminance data of each pixel (referred to as an image pixel) of an image obtained by photographing a liquid crystal display panel with a CCD camera, if the There are photographic pixels with abnormal brightness values in a part of the plurality of photosensitive elements (that is, pixels, also called photographic pixels) of the photographic element. Even if the inspected liquid crystal display panel has no bright spot defects, it is judged that there is a bright spot defect. In the case of a bright spot defect.

In other words, the technique disclosed in Patent Document 1 cannot determine whether the cause of the bright spot defect is the imaging element of the CCD camera or the liquid crystal display panel, so it cannot accurately determine the defect of the liquid crystal display panel.

In view of this, an object of the present invention is to provide an image generating apparatus and an image generating method that generate an image necessary for accurately determining a defect of a display panel.

In order to achieve the above-mentioned object, the first feature of the image generating apparatus of the present invention is to include: a mounting table for mounting a display panel as an object to be inspected; a photographing means is provided facing the display panel; and a calculating means is based on the above-mentioned For the image data captured by the photographing means, the average value of the brightness values of the surrounding pixels of the attention pixel is calculated as the average value of the surrounding pixels; When the difference between the pixel average values is greater than or equal to the set threshold value, it is determined that the imaging element of the imaging element corresponding to the pixel of interest is defective; When a photographing pixel of the photographing element corresponding to the photographing means is defective, the luminance value of the attention pixel is corrected to the average value of the surrounding pixels, and the corrected image data obtained by the correction is stored in the memory unit.

The second feature of the image generating apparatus of the present invention is that the defect determination means includes: threshold setting means for setting a dynamic value set based on the calculated average value of the surrounding pixels for each of the attention pixels. as the aforementioned threshold.

A third feature of the image generating apparatus of the present invention is that the calculation means, the defect determination means, and the correction means are constituted by an integrated circuit provided between the imaging means and the memory unit.

In order to achieve the above-mentioned object, the first feature of the image generation method of the present invention is that it can correct an image used for inspecting a display panel using a stage and a photographing means on which the display panel as an object to be inspected is placed, and the photographing means It is disposed opposite to the above-mentioned display panel, and the image generation method includes: a calculation step of calculating the average value of the brightness values of the surrounding pixels of the attention pixel based on the image data captured by the above-mentioned photographing means as the surrounding pixel average. value; a defect judgment step of judging the imaging element of the imaging means corresponding to the attention pixel when the difference between the luminance value of the attention pixel and the calculated average value of the surrounding pixels is equal to or greater than a set threshold value A photographing pixel is defective; and a correcting step is to correct the luminance value of the attention pixel to the peripheral value when the defect determination means judges that the photographing pixel of the photographing element of the photographing means corresponding to the attention pixel is defective The average value of the pixels is stored, and the corrected image data obtained by the aforementioned correction is stored in the memory unit.

According to the image generating apparatus and the image generating method of the present invention, it is possible to generate an image necessary for accurately determining a defect of a display panel.

1‧‧‧Video generation device

11‧‧‧Place

12‧‧‧Camera

15‧‧‧Panel drive signal generator

16‧‧‧Panel power supply

17‧‧‧Image processing device

19‧‧‧Input

20‧‧‧Output

20a‧‧‧Operation monitor

20b‧‧‧Video Monitor

101~109, 202~204, 206~209, 212~214, 216~219‧‧‧Pixel

120, 121‧‧‧differential

171‧‧‧Processing Department

171a, 174a‧‧‧Calculation means

171b, 174b‧‧‧Defect Judgment Methods

171c, 174c‧‧‧Threshold setting method

171d, 174d‧‧‧correction means

172‧‧‧Memory Department

173‧‧‧External Network Department

174‧‧‧Capture Card

205‧‧‧pixels (abnormal brightness point)

215‧‧‧pixels (abnormal brightness point)

P‧‧‧Display Panel

FIG. 1 is an explanatory diagram showing a schematic configuration of a video generating apparatus according to a first embodiment of the present invention.

FIG. 2 is a functional configuration diagram illustrating the configuration of the video processing device included in the video generation device 1 .

Fig. 3(a) is a diagram showing an example of an image obtained by a camera photographing the display panel; Fig. 3(b) is a diagram showing an abnormal point of luminance caused by a defect of the photographing element, where the luminance value is higher than that of the surroundings (due to the defect of the camera). Brightness abnormal point) is a graph of the brightness values of the adjacent image pixels in the same row; Figure 3(c) shows the brightness abnormal point (due to the brightness abnormal point of the panel) whose brightness value is higher than the surrounding due to the defect of the display panel ) is a graph of the luminance values of adjacent image pixels in the same row.

Figure 4 (a) is a diagram illustrating the attention pixel and surrounding pixels of the image captured by the camera; Figure 4 (b)~(d) shows the appearance of the attention pixel caused by the abnormal brightness of the camera. Figures 4 (e) to (g) are diagrams showing an example of the brightness value of each image pixel when the highlighted pixel appears at an abnormal point in brightness of the panel.

Fig. 5(a) shows the difference of each image pixel in the same column with its pixel relative to the surrounding pixels when the eye-catching pixel as shown in Fig. 3(b) is caused by the abnormal point of brightness of the camera. The ratio of the luminance value of the pixel of interest to the average value of the luminance value (brightness ratio); Fig. 5(b) shows that when the pixel of interest is an abnormal point of luminance caused by the panel, each pixel in the same column is The ratio (brightness ratio) of the luminance value of the pixel of interest to the average value of the luminance values of the surrounding pixels.

FIG. 6 is a flowchart showing the processing contents of the image generating apparatus according to the first embodiment.

FIG. 7 is a functional configuration diagram illustrating the configuration of a video processing device included in the video generation device according to the second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts and constituent elements are denoted by the same or equivalent symbols in the respective figures. However, it should be noted that the picture shown is a schematic diagram and may be different from the actual product. Of course, the respective figures also include differences in the relationship of dimensions, ratios, and the like.

In addition, the embodiments disclosed below illustrate devices and the like for embodying the technical idea of the present invention, and the technical idea of the present invention does not limit the material, shape, structure, arrangement, etc. of each component to those described below. The technical idea of the present invention can be variously changed within the scope of the patent application.

Embodiments of the image generating apparatus of the present invention will be described in detail below with reference to the accompanying drawings.

<First Embodiment>

FIG. 1 is an explanatory diagram showing a schematic configuration of a video generating apparatus according to a first embodiment of the present invention. In the following description, the horizontal direction of the paper surface of Fig. 1 is the X1-X2 direction, and the direction perpendicular to the paper surface of Fig. 1 is the Y1-Y2 direction (the direction that penetrates the paper surface is the Y1 direction, and the direction that penetrates the paper surface is the Y1 direction. The direction of the paper surface is the Y2 direction), and the up-down direction of the paper surface of FIG. 1 is the Z1-Z2 direction.

(Overall configuration of video generation device)

The image generating apparatus 1 according to the first embodiment of the present invention is suitable for use in a display panel inspection apparatus for inspecting the lighting state of the display panel P. As shown in FIG. As shown in FIG. 1, the image generation apparatus 1 of 1st Embodiment has the mounting base 11 on which the display panel P which is an object to be examined is mounted and fixed. The display panel P mounted on the mounting table 11 has display pixels arranged in a matrix along the X1-X2 direction and the Y1-Y2 direction.

Moreover, as shown in FIG. 1, above the center of the display panel P (Z1 direction), a camera 12 is arranged facing the display panel P as a photographing means. The camera 12 is a digital camera having photographic elements such as a CCD sensor and a CMOS sensor, and can obtain an image of the display state of the digital data type by photographing the display panel P on which the image is displayed. In this embodiment, each pixel of the image captured by the camera corresponds to each pixel (photographic pixel) of the light-sensing element constituting the imaging element of the camera on a one-to-one basis. The camera 12 is fixed by a camera fixing mechanism not shown.

In addition, the image generation device 1 includes a panel drive signal generator 15 , a panel power supply 16 , an image processing device 17 , an input unit 19 , and an output unit 20 .

The panel drive signal generator 15 causes the display panel P to display an inspection screen and the like according to an instruction from the image processing device 17 .

The panel power supply 16 supplies power to the display panel P. As shown in FIG.

The input unit 19 is, for example, a mouse, a keyboard, and the like for the operation of the image generating apparatus 1 and the input of information such as data, and is supplied to the image processing apparatus 17 .

The output unit 20 displays a screen or the like in accordance with an instruction from the video processing device 17, and includes an operation monitor 20a and a video monitor 20b. The operation monitor 20a displays a screen for performing operations, various settings, data input, and operation status display of the video generation device 1 and its components (camera 12, panel drive signal generator 15, panel power supply 16), and the like. The video monitor 20b displays the video captured by the camera 12, the corrected video obtained by correcting the video by the video processing device 17, and the like.

The image processing device 17 may be constituted by a general-purpose computer such as a PC (personal computer). The image processing device 17 controls external devices such as the camera 12 , the panel drive signal generator 15 , the panel power supply 16 , and the like, performs processing for generating a screen to be displayed on the display panel P, and corrects the image captured by the camera 12 , and Processing and the like are performed to identify defective pixels of the display panel P based on the corrected image after the correction.

FIG. 2 is a functional configuration diagram illustrating the configuration of the video processing device 17 included in the video generation device 1 .

As shown in FIG. 2 , the image processing apparatus 17 includes a processing unit 171, and the processing unit 171 is a functional block realized by a program and a CPU that executes various processes according to the program. Furthermore, the processing unit 171 is connected to the memory unit 172 that stores various data.

The data stored in the memory unit 172 include, for example, various programs for realizing the processing unit 171, screen data determined by the processing unit 171 to be displayed on the display panel P during inspection, image data captured by the camera 12, Corrected image data corrected by the processing unit 171, various data determined by calculation to identify defective pixels, data used to control various external devices, various data stored as a work area, and the image processing device 17, measurement Various data for setting conditions required for various processing, such as objects and camera specifications. The storage unit 172 is realized by a storage medium such as a memory and a hard disk. In addition, the processing unit 171 is connected to an external network unit 173 for connecting with various external devices, and the input unit 19 , the output unit 20 , the camera 12 , the panel drive signal generator 15 , the input unit 19 , the output unit 20 , the camera 12 , the panel drive signal generator 15 , The panel is connected to an external device such as a power supply 16 and transmits and receives data.

In the processing unit 171 of the image processing device 17, a dummy calculation means 171a, defects, etc. are constructed by the execution program, various data, etc. stored in the memory unit 172, and the calculation processing of the CPU or the like executed according to the program, data, etc. The determination means 171b, and the correction means 171d. Among them, the defect determination means 171b includes a threshold value setting means 171c.

As described above, the camera 12 can obtain a photographed image of the display state by photographing the display panel P on which the image is displayed. At this time, there may be cases where the photographic pixel itself of the photographing element of the camera 12 has a defect (photographic pixel defect). There are various reasons for the occurrence of this photographic pixel defect, such as: abnormal sensitivity to light caused by the deterioration of the photographic pixel, etc.; there are also reproducible occurrences at a fixed position on a certain photographic element. Photographic pixel defects; there are also photographic pixel defects without position reproducibility, such as abnormal sensitivity to light, which randomly occurs on the photographic element due to poor characteristics of the photographic element.

When the imaging element of the camera 12 has a pixel defect, even if the display panel P, which is the inspection object, does not have a bright spot defect (display pixel defect), a bright spot will appear on the image captured by the camera 12. The brightness value of the component is higher than the surrounding brightness abnormal point.

Fig. 3 shows the abnormal point of brightness caused by the brightness value of the photographing element being higher than that of the surrounding (due to the abnormal point of brightness of the camera), and the abnormal point of brightness caused by the brightness value of the display panel being higher than that of the surrounding (due to the brightness of the panel). An explanatory diagram of an abnormal point).

FIG. 3( a ) is a diagram showing an example of a photographed image obtained by photographing the display panel P by the camera 12 .

In the example shown in FIG. 3( a ), an abnormal brightness point 205 due to the camera and an abnormal brightness point 215 due to the panel appear in the form of bright spots on the captured image.

Fig. 3(b) is a graph showing the luminance values of the image pixels in the same row adjacent to the luminance anomaly point 205 caused by the camera, and Fig. 3(c) is a graph showing the luminance value adjacent to the luminance anomaly point 215 caused by the panel A graph of the luminance values of image pixels in the same row. In Fig. 3, the luminance value detected by each pixel of the imaging element of the camera 12 is displayed on the corresponding image pixel. This brightness value represents the sensitivity to light, and the higher the brightness, the higher the brightness value.

As shown in FIG. 3(b), only the brightness value of the brightness abnormal point 205 caused by the camera is higher than the brightness value of the adjacent image pixels in the same row (X1-X2 direction). In particular, the luminance values of the image pixels 204 and 206 adjacent to the luminance abnormal point 205 are substantially the same as the luminance values of the image pixels 202 to 203 and 207 to 209 . In other words, since only the luminance value caused by the abnormal brightness point 205 of the camera exhibits an abnormally high value, it can be presumed that there is a photographic image in the photographing element of the camera 12 corresponding to the abnormal point of brightness 205 caused by the camera. element defects.

On the other hand, in FIG. 3(c), the luminance value of the luminance abnormal point 215 caused by the panel is at a peak value, and the luminance values of the adjacent image pixels 214 and 216 caused by the luminance abnormal point 215 of the panel are also higher than The image pixels 211 and 218 have high luminance values. That is, not only the brightness value of the abnormal brightness point 215 caused by the panel is high, but the brightness value of the pixel adjacent to the abnormal brightness point 215 is also higher as it is closer to the abnormal brightness point 215 caused by the panel.

As described above, the light emitted from each display pixel of the display panel P is incident on the imaging element through the lens of the camera 12 . The camera 12 can convert the light incident into its photographic element into electrical signals to obtain a photographed image in the form of digital data. Therefore, when the display panel P has a bright spot defect (display pixel defect), the light emitted from the display pixel having the bright spot defect (display pixel defect) is incident on a plurality of photographic images through an optical system such as a lens of the camera 12 . white. Therefore, a plurality of photographic pixels of the camera 12 obtain high luminance values.

In the example shown in FIG. 3(c), since the brightness value of the brightness abnormal point 215 caused by the panel is at a peak value, and the brightness value of the image pixel adjacent to the brightness abnormal point 215 caused by the panel also appears to be higher. The higher the brightness abnormal point 215 caused by the panel, the higher it is. Therefore, it can be presumed that the camera 12 is not defective in the photographic pixels (photographic pixel defect), but the display pixel of the display panel P has a bright spot defect (display pixel defect). .

As mentioned above, the captured image captured by the camera 12 may include the abnormal brightness point 205 caused by the camera due to the defect of the photographic pixel, and the abnormal brightness point 215 caused by the panel caused by the defect of the display pixel, Therefore, in the lighting inspection of the display panel P, it is necessary to detect the display pixel defect of the display panel P by removing the abnormal brightness point 205 caused by the camera. That is, it must be determined whether the bright spot abnormal point is caused by the camera 12 or the display panel P.

On the other hand, in the image generating apparatus 1 of the first embodiment, the calculating means 171a first calculates the average value of the luminance values of the image pixels located around the attention pixel based on the image captured by the camera 12 as the surrounding pixel average value.

FIG. 4( a ) is a diagram illustrating the attention pixel and surrounding pixels of the image captured by the camera 12 .

If the image pixel 105 is used as the attention pixel, the eight image pixels 101 to 104 and 106 to 109 surrounding the attention pixel 105 are the surrounding pixels. On the other hand, the calculating means 171a calculates the average value of the luminance values of the surrounding pixels 101 to 104 and 106 to 109 as the surrounding pixel average value.

The defect judgment means 171b judges that the difference between the luminance value of the attention pixel 105 and the calculated average value of the surrounding pixels is equal to or larger than a set threshold value, and determines as the imaging pixel of the imaging element of the camera 12 corresponding to the attention pixel 105 defective.

Figures 4 (b) to (d) are diagrams showing an example of the luminance value of each image pixel when the attention pixel 105 appears due to the white spot of the camera. Figure 4 (e) to ( g) is a diagram showing an example of the luminance value of each image pixel when the attention pixel 105 appears at an abnormal point in luminance of the panel.

As shown in FIGS. 4 (b) to (d), when the attention pixel 105 appears at an abnormal point of luminance caused by the camera, only the luminance value of the attention pixel 105 becomes abnormally higher than the surrounding pixels.

The calculation means 171 a calculates the average value of the luminance values of the surrounding pixels 101 to 104 and 106 to 109 as the surrounding pixel average value 110 .

Then, when the difference 120 between the luminance value of the attention pixel 105 and the calculated average value 110 of the surrounding pixels is equal to or larger than the set threshold value Th, the defect judgment means 171b judges that the pixel of the camera 12 corresponding to the attention pixel 105 is a photographing pixel of the camera 12 defective. The threshold value Th is determined by the threshold value setting means 171c included in the defect determination means 171b. Details will be described later.

In the example shown in FIG. 4( c ), since the attention pixel 105 has an abnormal point of luminance caused by the camera, the luminances of the surrounding pixels 101 to 104 and 106 to 109 are smaller than the luminance of the attention pixel 105 A lot of value. That is, since the difference 120 is larger than the set threshold Th, the defect determination means 171b determines that the imaging pixel of the camera 12 corresponding to the attention pixel 105 is defective (photographic pixel defect).

On the other hand, as shown in FIGS. 4 (e) to (g), when the attention pixel 105 appears at an abnormal point in luminance caused by the panel, not only the luminance value of the attention pixel 105, but also the luminance values of the surrounding pixels becomes higher value.

The calculating means 171 a calculates the average value of the luminance values of the surrounding pixels 101 to 104 and 106 to 109 as the surrounding pixel average value 111 .

In the example shown in FIG. 4( f ), the attention pixel 105 appears at an abnormal point in brightness of the panel, and the brightness values of the peripheral pixels 101 to 104 and 106 to 109 also have high values. That is, since the difference 121 is too small to exceed the set threshold Th, the defect determination means 171b determines that the display pixel of the display panel P is not defective but the display pixel of the display panel P is defective (display pixel defect).

In this way, it is possible to distinguish between the brightness abnormal point caused by the camera and the display pixel defect caused by the abnormal brightness point of the panel.

Then, when the defect determination means 171b determines that the imaging pixel of the camera 12 corresponding to the attention pixel 105 is defective, the correction means 171d corrects the luminance value of the attention pixel 105 to the average value of the surrounding pixels. The correction means 171 d stores, in the storage unit 172 , the corrected image data corrected with each image pixel of the captured image as the attention pixel 105 .

Thereby, the correction image data used for the lighting inspection of the display panel P and the abnormal point of brightness caused by the camera removed from the captured image can be stored in the memory unit 172 .

In addition, as for the setting of the threshold, it is preferable to use a dynamic threshold (variable threshold) created according to the luminance value of the surrounding pixels for each pixel of interest. When setting the variable threshold value, for example, the threshold value can be created from a value obtained by multiplying the average value of luminance values of surrounding pixels by a fixed coefficient. Thereby, the threshold value also changes every time the attention pixel changes, so the threshold value can be dynamically changed. By using such a determination method using a variable threshold value, it is possible to monitor the increase ratio of the luminance value of the attention pixel relative to the luminance value of the surrounding pixels, so that the cause can be more accurately determined than the case of using a fixed threshold value. Distinguish between the abnormal brightness point of the camera and the abnormal point of brightness caused by the panel.

Here, the determination of the threshold Th by the threshold setting means 171c will be described in more detail.

In order to remove the brightness abnormal point due to the camera from the captured image but leave the brightness abnormal point due to the panel, the threshold Th for distinguishing the brightness abnormal point due to the panel and the brightness abnormal point due to the camera must be appropriately set.

As shown in Figure 3(b), when only the brightness value of an image pixel at a certain point is higher than the brightness value of the surrounding pixels, it can be inferred that the image pixel is caused by the abnormal brightness of the camera, as shown in Figure 3 As shown in (c), when a certain image pixel has a high luminance value, and the luminance value of its image pixel has a peak value, and the closer the pixel is to the image pixel, the higher the luminance value, the image pixel can be inferred. It is caused by the abnormal point of brightness of the panel.

Therefore, for example, if the threshold is set to a fixed value and the difference between the luminance values of adjacent video pixels is simply the threshold value or more, it is determined that the luminance abnormal point is caused by the camera, as shown in Fig. 3(c) If the difference between the luminance values of the image pixel 215 and the adjacent image pixel 214 is too large, the image pixel 215 may be mistakenly regarded as an abnormal point of luminance caused by the camera.

On the other hand, the threshold value setting means 171c changes the threshold value Th for each pixel of interest. Specifically, for each pixel of interest, a value obtained by multiplying the calculated average value of surrounding pixels by a preset threshold magnification TR is set as the threshold Th. Here, in order to prevent the threshold value Th from being "0", it is preferable to use a value obtained by adding the offset value to the threshold value Th as the threshold value Th. The threshold magnification TR is determined by the user according to the ratio (brightness ratio) of the luminance value of the attention pixel relative to the average value of the surrounding pixels when the abnormal point of brightness caused by the camera occurs, and when the abnormal point of brightness caused by the panel occurs. The luminance ratio is inputted from the input unit 19 in advance to distinguish the luminance abnormal point caused by the camera and the luminance abnormal point caused by the panel.

Fig. 5(a) shows that in the case where the image pixel 205 shown in Fig. 3(b) is caused by an abnormal point of brightness of the camera, among the image pixels in the same row as the image pixel 205, relative to The ratio (brightness ratio) of the brightness value of the attention pixel to the average value of the surrounding pixels is the same as the image pixel 205 when the image pixel 215 is the abnormal point of brightness caused by the panel in Fig. 5(b). The ratio (brightness ratio) of the luminance value of the attention pixel with respect to the average value of the surrounding pixels in each image pixel in the row.

As shown in FIG. 5(a), when the pixel 205 is an abnormal point of brightness caused by the camera, the brightness ratio of the image pixel 205 is sufficiently large compared to the brightness ratios of the pixels 202-204 and 206-209. value.

On the other hand, as shown in FIG. 5(b), when the pixel 215 is an abnormal point of brightness caused by the panel, although the brightness ratio of the pixel 215 is larger than the brightness ratio of the pixels 212-214 and 216-219, the difference is Small.

Therefore, if the threshold magnification TR is set too low, there is a possibility that the defect determination means 171b erroneously determines the brightness abnormal point caused by the panel as the brightness abnormal point caused by the camera.

In this regard, the user presets an appropriate threshold magnification TR capable of distinguishing the brightness abnormal point caused by the camera from the brightness abnormal point caused by the panel. In the example shown in FIG. 5, the threshold magnification TR is set to 150% (1.5 times) of the average value of the surrounding pixels.

In this way, the abnormal brightness point caused by the camera and the abnormal brightness point caused by the panel can be distinguished, so the abnormal point of brightness caused by the camera can be excluded, and only the bright spot defect of the display panel P can be detected.

FIG. 6 is a flowchart showing the processing contents of the image generating apparatus 1 according to the first embodiment.

As shown in FIG. 6 , the camera 12 acquires a photographed image of the display state by photographing the display panel P on which the image is displayed (step S101 ). The number of rows and columns of pixels of the acquired image is registered or preset at this time. The number of rows and columns of pixels in the video is used for determination in steps S117 and S119 to be described later.

Next, the calculating means 171a designates one pixel of the acquired captured image as the attention pixel of the origin (step S103). Here, the pixels of the captured image are arranged in a matrix in a rectangular image area, and the pixel located at the upper left corner of the image is set as the attention pixel at the origin (0, 0), and the first pixel is counted from the top. The arrangement direction of the pixels in the column is the X axis, and the arrangement direction of the pixels in the first row from the left is the Y axis.

Then, the calculating means 171a sums up the luminance values of eight pixels (peripheral pixels) around the designated attention pixel based on the captured image captured by the camera 12 (step S105), and then calculates the sum of the luminance values. The sum of the luminance values of the surrounding pixels is divided by the number of surrounding pixels "8" to calculate the average value of surrounding pixels (step S107). In addition, when the pixel of interest is located at a corner, the luminance values of the three surrounding pixels (peripheral pixels) are added up and divided by the number of surrounding pixels "3". When the pixel of interest is located on the edge other than the corner, the luminance values of the five surrounding pixels (peripheral pixels) are added up and divided by the number of surrounding pixels "5".

The calculating means 171a calculates the difference between the luminance value of the designated attention pixel and the calculated average value of the surrounding pixels (step S109).

The threshold value setting means 171c sets, as the threshold value Th, a value obtained by multiplying the calculated average value of surrounding pixels by a preset threshold value magnification TR (step S111).

Next, the defect determination means 171b adds an offset value to the threshold value Th set in step S111, and sets it as a new threshold value Th (step S113). The average value of surrounding pixels may also be "0". When the average value of surrounding pixels is "0", it is still "0" even if multiplied by the threshold magnification TR. On the other hand, in order to prevent the threshold value Th from becoming "0", the defect determination means 171b adds a value such as "150", which is an offset value, to the threshold value Th to set a new threshold value Th. The offset value is a preset value.

The defect determination means 171b compares whether the difference between the luminance value of the attention pixel calculated in step S109 and the average value of surrounding pixels is equal to or larger than the threshold Th set in step S113 (step S114).

As a result of the comparison, if it is determined that the difference between the luminance value of the attention pixel and the average value of the surrounding pixels is greater than the threshold Th set in step S113 (YES in step S115 ), the defect determination means 171b determines the difference between the attention pixel and the average value of the attention pixel. When a pixel defect occurs in the corresponding imaging element of the camera 12, the correction means 171d corrects the luminance value of the pixel of interest to the average value of the surrounding pixels (step S116). If it is determined that the difference between the luminance value of the attention pixel and the average value of surrounding pixels is equal to or less than the threshold Th set in step S113 (NO in step S115 ), the process proceeds to the next step without performing correction.

Next, the correction means 171d determines whether or not the attention pixel is the last pixel in the row (whether it is the rightmost pixel). That is, it is determined whether or not the value of X of the coordinates of the pixel of interest is equal to the number of rows of the image pixel array (step S117). If it is determined that it is not the last pixel in the row (NO in step S117), the coordinate value of X is incremented by 1 (step S118), the next pixel of interest is designated (step S104), and the following steps are performed processing. If it is determined that it is the last pixel (the rightmost pixel) in the row (YES in step S117 ), it is determined whether or not the pixel of interest is the last row. That is, it is determined whether the value of Y of the coordinate of the pixel of interest is equal to the number of columns of the image pixel array (step S119). If the pixel of interest is not the last column (“NO” in step S119 ), the coordinate value of X is set to 0 and the coordinate value of Y is incremented by 1 (step S120 ), and the next pixel of interest is designated (step S104 ), The processing of the subsequent steps is performed. If it is determined that the pixel of interest is the last row (YES in step S119 ), the correction means 171d stores the captured image data in the storage unit 172 when the correction has not been performed, and stores the captured image data in the storage unit 172 when the correction is performed. The corrected image data after correction is stored in the storage unit 172 (step S121). Then, the captured image data obtained by the above-mentioned processing is used for the judgment processing of display pixel defects, and the like.

As described above, the image generating apparatus 1 according to the first embodiment includes: the mounting table 11 on which the display panel P, which is the object to be inspected, is mounted; the camera 12 arranged to face the display panel P; The average value of the brightness values of the surrounding pixels of the attention pixel is calculated as the average value of the surrounding pixels as the calculation means 171a; the difference between the brightness value of the attention pixel and the calculated average value of the surrounding pixels is set as Defect judgment means 171b for judging that the imaging element of the camera 12 corresponding to the pixel of interest has a imaging pixel defect when the threshold value is greater than or equal to the threshold value; When a photographic pixel defect occurs in the photographic pixel, the luminance value of the pixel of interest is corrected to the average value of the surrounding pixels, and the corrected image data obtained by the correction is stored in the correction means 171d of the storage unit 172 .

Therefore, even if the image captured by the camera 12 includes abnormal brightness points due to photographic pixel defects (due to the abnormal brightness points of the camera) and abnormal brightness points due to display pixel defects (due to the abnormal brightness of the panel) In the case of abnormal brightness points), it is also possible to distinguish the abnormal brightness points caused by the camera from the abnormal brightness points caused by the panel. Therefore, the abnormal point of photographing brightness can be excluded by correction, and only the bright spot defect of the display panel P can be detected, so that the defect of the display panel P can be accurately determined.

<Second Embodiment>

The image generation device 1 according to the first embodiment of the present invention executes a program by the processing unit 171 to virtually construct the calculation means 171a, the defect determination means 171b, the threshold value setting means 171c, and the correction means 171d, but it is not limited to this, and the A calculation means, a defect determination means, a threshold value setting means, and a correction means are mounted on the integrated circuit.

The second embodiment of the present invention is an example of an image generating apparatus 1 in which calculation means, defect determination means, threshold value setting means, and correction means are mounted using an integrated circuit.

FIG. 7 is a functional configuration diagram illustrating the configuration of the video processing device 17 included in the video generation device 1 according to the second embodiment of the present invention.

As shown in FIG. 7, the image processing apparatus 17 of the image generating apparatus 1 according to the second embodiment of the present invention includes a capture card 174 having an integrated circuit.

The capture card 174 is equipped with a calculation means 174a, a defect determination means 174b, a threshold value setting means 174c, and a correction means 174d using an integrated circuit. Among them, the processing contents of the calculation means 174a, the defect determination means 174b, the threshold value setting means 174c, and the correction means 174d are the same as those of the calculation means 171a, the defect determination means 171b, the threshold value setting means 171c, and the correction means in the first embodiment described above. The means 171d is performed based on the same concept, and the flow of the processing in the first embodiment shown in FIG. 6 can also be applied to the second embodiment.

Specifically, the calculation means 174a includes an addition circuit and a division circuit. The addition circuit sums the brightness values of the surrounding pixels of the attention pixel according to the image data captured by the camera 12 , and the division circuit divides the summed value by the number of surrounding pixels to calculate the average value of surrounding pixels. . The number of surrounding pixels is, for example, "3" when the pixel of interest is located at the corner, "5" when the pixel of interest is located on the edge, and "8" when the pixel of interest is located at other positions.

The defect determination means 174b includes a subtraction circuit and a selection circuit. The subtraction circuit calculates the difference by subtracting the average value of surrounding pixels from the luminance value of the pixel of interest. Then, the threshold Th is subtracted from the difference. When the value obtained by subtracting the threshold Th from the difference is a positive value, the selection circuit sends a signal representing an abnormal point of brightness caused by a pixel defect of the camera (an abnormal point of brightness caused by the camera) to the correction means 174d, When the value obtained by subtracting the threshold Th from the difference is a negative value, a signal indicating an abnormal point of luminance not caused by a pixel defect of the camera is sent to the correction means 174d.

The threshold value setting means 174c includes a multiplying circuit. The multiplication circuit multiplies the average value of the surrounding pixels by the threshold value magnification TR input from the outside, and supplies the threshold value Th to the selection circuit.

The correction means 174d corrects the brightness value of the image pixel, which is supplied from the defect determination means 174b and indicates an abnormal point of brightness caused by the camera, to the average value of the surrounding pixels and stores it in the memory unit 172, and stores the defect determination means 174b. The image pixels indicating that the supply is not caused by the abnormal point of brightness of the camera are stored in the memory unit 172 without being corrected.

As described above, in the image generating apparatus 1 according to the second embodiment of the present invention, the capture card 174 is provided on the downstream side of the camera 12 and on the upstream side of the memory unit 172, and the calculation means 174a is constituted by an integrated circuit , a defect determination means 174b, a threshold value setting means 174c, and a correction means 174d.

Therefore, when the images captured by the camera 12 are sequentially supplied from the external network unit 173 to the capture card 174 in the form of captured image data, the capture card 174 executes the processing in sequence according to the supplied order, and will The image data (corrected image data) is stored in the storage unit 172 . Therefore, since the processing is performed continuously, the time until the processing is completed can be significantly shortened compared to the virtual construction of the calculation means, the defect determination means, the threshold value setting means, and the correction means by executing the program. In addition, if the integrated circuit of the capture card 174 is a semiconductor chip with a rewritable circuit (such as a Field Programmable Gate Array (FPGA)), it can be adapted to the measurement object, photographing means, etc. It is better to easily customize various means according to the specifications.

12‧‧‧Camera

15‧‧‧Panel drive signal generator

16‧‧‧Panel power supply

17‧‧‧Image processing device

19‧‧‧Input

20‧‧‧Output

171‧‧‧Processing Department

171a‧‧‧Means of calculation

171b‧‧‧Defect Judgment Means

171c‧‧‧Threshold setting method

171d‧‧‧Means of Correction

172‧‧‧Memory Department

173‧‧‧External Network Department

Claims (5)

An image generating device, comprising: a mounting table for mounting a display panel as an object to be inspected; a photographing means arranged to face the display panel; and a calculating means for calculating based on image data captured by the photographing means The average value of the brightness values of the surrounding pixels of the attention pixel is regarded as the average value of the surrounding pixels; the defect judgment means is to use the difference between the luminance value of the attention pixel and the calculated average value of the surrounding pixels as the set threshold value. In the above case, it is determined that the imaging element of the imaging device corresponding to the pixel of interest is defective; and the correction means is to determine the imaging element of the imaging device corresponding to the pixel of interest by the defect determination means. When a defect occurs in a photographic pixel, the luminance value of the attention pixel is corrected to the average value of the surrounding pixels, and the corrected image data obtained by the correction is stored in the storage unit, and the defect judgment means includes: a threshold value setting means , the threshold value is set according to each of the above-mentioned attention pixels, and the above-mentioned threshold value setting means is based on each of the above-mentioned attention pixels, based on the calculated average value of the above-mentioned surrounding pixels and the preset fixed threshold value magnification to calculate the dynamic value The value of , is set as the aforementioned threshold value, and the aforementioned threshold value magnification is the ratio of the increase of the brightness value of the attention pixel relative to the average value of the surrounding pixels to distinguish the brightness abnormal point caused by the panel and the brightness abnormal point caused by the camera. , the abnormal brightness point caused by the panel is caused by the defect of the aforementioned display panel and the brightness value is higher than the surrounding If the brightness is higher, the abnormal point of brightness caused by the camera is caused by the defect of the aforementioned photographing means and the brightness value is higher than the surrounding. The image generating device according to claim 1, wherein the threshold setting means multiplies the calculated average value of the surrounding pixels by the threshold magnification plus an offset value for each of the attention pixels The subsequent value is set as the aforementioned threshold value. The image generating apparatus according to claim 1, wherein the calculating means, the defect determining means, and the correcting means are constituted by integrated circuits provided between the photographing means and the memory unit. An image generation method for correcting an image used for inspecting a display panel using a mounting table and a photographing means, the mounting table placing the display panel as an object to be inspected, the photographing means being provided opposite to the display panel, and the image The generating method includes: a calculating step of calculating the average value of the brightness values of the surrounding pixels of the attention pixel based on the image data captured by the aforementioned photographing means as the surrounding pixel average value; the threshold value setting step is based on each of the aforementioned The threshold value is set for the attention pixel; in the defect determination step, when the difference between the brightness value of the attention pixel and the calculated average value of the surrounding pixels is greater than or equal to the set threshold value, the step corresponding to the attention pixel is judged. A photographing pixel of a photographing element of the photographing means is defective; and a correcting step is, when the defect determining means judges that a photographing pixel of the photographing element of the photographing means corresponding to the above-mentioned pixel of interest is defective, correcting the photographing pixel of the above-mentioned attentional pixel. The brightness value is corrected to the average value of the aforementioned peripheral pixels, and the corrected image data obtained by the aforementioned correction is stored in the memory unit, The threshold value set in the above-mentioned threshold value setting step is: a dynamic value calculated according to each of the above-mentioned attention pixels, according to the calculated average value of the above-mentioned surrounding pixels, and a preset fixed threshold value magnification, and the above-mentioned threshold value magnification is used. In order to distinguish the brightness abnormal point caused by the panel and the brightness abnormal point caused by the camera, the increase ratio of the brightness value of the attention pixel relative to the average value of the surrounding pixels, the brightness abnormal point caused by the panel is caused by the aforementioned If the display panel is defective and the brightness value is higher than the surrounding area, the abnormal brightness point caused by the camera is caused by the defect of the aforementioned photographing means and the brightness value is higher than the surrounding area. The image generation method according to claim 4, wherein the threshold setting step is to multiply the calculated average value of the surrounding pixels by the threshold magnification plus an offset value for each of the noticeable pixels The subsequent value is set as the aforementioned threshold value.

Images