Region detection apparatus and defect inspection apparatus

Abstract

To provide a technique advantageous for improving the accuracy of detecting a display region.SOLUTION: There is provided a region detection apparatus for detecting a display region from an inspection image photographed in a state where the display region of a display device is lit, the region detection apparatus scanning a plurality of lines set so as to intersect with sides constituting the outer edge of the display region and specifying the display region by detecting coordinate positions of the sides on the basis of pixel values of pixels of each of the plurality of lines.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an area detection device and a defect inspection device. [Background technology]

[0002] As sensor panels mounted on imaging devices become larger and more pixelated, a method for analyzing inspection images of a display device has been proposed for inspecting defects in display devices. When performing defect inspection using an inspection image, it is necessary to detect the display area of ​​the display device as the inspection area. Patent Document 1 shows that a black image and a white image are displayed on a color liquid crystal display panel, and the circumscribed area of ​​the portion of the image where the grayscale values ​​differ by more than a predetermined value is determined, and the circumscribed area is set as the inspection area within the image. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Publication No. 2001-083474 Summary of the Invention [Problem to be solved by the invention]

[0004] If the inspection image contains data of abnormal signal levels, such as bright spots, outside the captured display area due to defects in the sensor panel, the operation described in Patent Document 1 may result in an erroneous determination of the edge of the display area.

[0005] An object of the present invention is to provide a technique that is advantageous in improving the accuracy of detection of a display area. [Means for solving the problem]

[0006] In view of the above problems, an area detection device according to an embodiment of the present invention is an area detection device for detecting a display area from an inspection image captured with the display area of ​​a display device turned on, and is characterized in that the area detection device identifies the display area by scanning a plurality of lines that are set to intersect with the sides that form the outer edge of the display area, and detecting the coordinate positions of each side based on the pixel values ​​of each pixel of the plurality of lines. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a technique that is advantageous in improving the accuracy of detection of a display area. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a defect inspection apparatus including an area detection apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing an example of a processing flow of the defect inspection apparatus of FIG. 1. [Figure 3] FIG. 2 is a diagram showing an example of the configuration of the area detection device shown in FIG. 1; [Figure 4] FIG. 2 is a diagram showing the relationship between defects in an inspection image and scan lines that scan the inspection image. [Figure 5] FIG. 3 is a diagram for explaining the arrangement of scan lines for scanning an inspection image. [Figure 6] FIG. 1 is a diagram showing an example of the configuration of a defect inspection apparatus including an area detection apparatus according to an embodiment of the present invention. [Figure 7] FIG. 7 is a diagram showing an example of the configuration of the area detection device in FIG. 6. [Figure 8] FIG. 2 is a diagram showing the relationship between defects in an inspection image and scan lines that scan the inspection image. [Figure 9] FIG. 3 is a diagram for explaining the arrangement of scan lines for scanning an inspection image. [Figure 10] FIG. 1 is a diagram showing an example of the configuration of a defect inspection apparatus including an area detection apparatus according to an embodiment of the present invention. [Figure 11] FIG. 11 is a diagram showing an example of a processing flow of the defect inspection apparatus of FIG. [Figure 12] FIG. 12 is a diagram showing an example of the configuration of the area detection device in FIG. [Figure 13] FIG. 3 is a diagram for explaining the arrangement of scan lines for scanning an inspection image. [Figure 14] FIG. 11 is a diagram showing an example of a processing flow of the area detection device in FIG. [Figure 15] FIG. 11 is a diagram showing an example of a processing flow of the area detection device in FIG. [Figure 16] FIG. 11 is a diagram showing an example of a processing flow of the area detection device in FIG. [Figure 17] FIG. 11 is a diagram showing an example of a processing flow of the area detection device in FIG. [Figure 18] FIG. 1 is a diagram showing an example of the configuration of a defect inspection apparatus including an area detection apparatus according to an embodiment of the present invention. [Figure 19] FIG. 19 is a diagram showing an example of the configuration of the area detection device in FIG. 18. [Figure 20] FIG. 3 is a diagram for explaining the arrangement of scan lines for scanning an inspection image. [Figure 21] FIG. 19 is a diagram showing an example of a processing flow of the area detection device in FIG. 18. [Figure 22] FIG. 19 is a diagram showing an example of a processing flow of the area detection device in FIG. 18. [Figure 23] FIG. 19 is a diagram showing an example of a processing flow of the area detection device in FIG. 18. [Figure 24] FIG. 19 is a diagram showing an example of a processing flow of the area detection device in FIG. 18. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] 1 to 24, a defect inspection apparatus according to an embodiment of the present disclosure and an area detection apparatus disposed in the defect inspection apparatus will be described. FIG. 1 is a block diagram showing an example configuration of a defect inspection apparatus 100 including an area detection apparatus 103 according to this embodiment. The defect inspection apparatus 100 includes an image acquisition unit 101, an image memory 102, an area detection device 103, and a defect inspection unit 105. The image acquisition unit 101 acquires an inspection image of a display device 107 to be inspected. The image memory 102 stores image data of the inspection image acquired by the image acquisition unit 101. The area detection device 103 detects a display area from an inspection image captured with the display area of ​​the display device 107 turned on. A threshold value for detecting the display area is input to the area detection device 103. The defect inspection unit 105 inspects the display area identified by the area detection device 103 for defects. The defect inspection unit 105 outputs the inspection results.

[0011] 2 shows a processing flow of the defect inspection apparatus 100. First, in S200, the display device 107 is turned on. For example, the display device 107 may display a white image in response to a signal output from the image acquisition unit 101. Next, in S201, the image acquisition unit 101 captures an image of the display device 107 to acquire an inspection image. Image data of the acquired inspection image is stored in the image memory 102.

[0012] Once the inspection image (image data) is acquired, the area detection device 103 performs a step of detecting a display area from the inspection image. Here, the inspection image is described as being rectangular, as shown in Figure 5, and composed of pixels arranged in a matrix in the x and y directions. The following description will be made using the top, bottom, left, and right of the inspection image 500 in Figure 5.

[0013] First, in S202, the area detection device 103 reads from the image memory 102 image data for scanning pixel values ​​from pixels located at the left edge of the inspection image 500, and detects the coordinate position xstart of the left-most side that forms the outer edge of the display area 501. Next, in S203, the area detection device 103 reads from the image memory 102 image data for scanning pixel values ​​from pixels located at the right edge of the inspection image 500, and detects the coordinate position xend of the right-most side that forms the outer edge of the display area 501. Next, in S204, the area detection device 103 reads from the image memory 102 image data for scanning pixel values ​​from pixels located at the top edge of the inspection image 500, and detects the coordinate position ystart of the top-most side that forms the outer edge of the display area 501. Furthermore, in S205, the area detection device 103 reads from the image memory 102 image data for scanning pixel values ​​from pixels located at the bottom edge of the image, and detects the coordinate position yend of the bottom-most side that forms the outer edge of the display area 501.

[0014] When the respective coordinate positions xstart, ystart, xend, and yend are detected, in S206, the coordinate positions xstart, ystart, xend, and ystart of each side of the detected display area 501 are output from the area detection device 103 to the defect inspection unit 105. The area detection device 103 detects the coordinate positions of each side that constitutes the outer edge of the display area 501, thereby identifying the display area 501 from the inspection image 500. In S207, the defect inspection unit 105 performs an operation to detect defects in the display area 501 identified by the area detection device 103.

[0015] FIG. 3 is a diagram illustrating an example of the configuration of the area detection device 103. The area detection device 103 scans multiple lines set to intersect with the sides that form the outer edge of the display area 501 and detects the coordinate positions of each side based on the pixel values ​​of each pixel on the multiple lines. For example, as shown in FIG. 4, data of abnormal signal levels, such as bright spots, may be recorded in the inspection image 500 due to defects in the sensor panel of the image acquisition unit 101. FIG. 4 illustrates a cross-shaped defect 400 with a width of three pixels. To prevent the bright spot shown in the defect 400 from being mistakenly detected as a side that forms the outer edge of the display area 501, the area detection device 103 scans lines that are larger than the defect 400, for example, five pixels wide, and detects the coordinate positions of the sides that form the outer edge of the display area 501. For example, the defect inspection device 100 may include a storage unit that stores the size of defects that appear in the inspection image 500 according to the characteristics of the image acquisition unit 101. As a result, the range in which the multiple lines scanned by the area detection device 103 are arranged in the direction along the side that forms the outer edge of the display area 501 may be set to be larger than the size of the defect 400 stored in the storage unit. For example, the size of the defect may be stored in the image memory 102.

[0016] The area detection device 103 may include a memory control unit 301, comparators 302 to 306 for comparing image data of each line with a threshold value, an AND circuit 308, and a coordinate acquisition unit 309. Image data of an inspection image 500 is input from the image memory 102 to the area detection device 103 via the memory control unit 301. A threshold value for detecting a display area 501 is input to the comparators 302 to 306. The coordinate acquisition unit 309 outputs the obtained coordinate positions xstart, ystart, xend, and yend of each side constituting the outer edge of the display area 501 to the defect inspection unit 105.

[0017] Next, the operation of area detection device 103 will be described with reference to Fig. 5. Fig. 5 shows an inspection image 500 and a display area 501. A plurality of lines 502 are five lines scanned to detect the coordinate position xstart of the leftmost side that constitutes the outer edge of display area 501. Similarly, a plurality of lines 503, 504, and 505 are five lines scanned to detect the coordinate position xend of the rightmost side, the coordinate position ystart of the topmost side, and the coordinate position yend of the bottommost side that constitute the outer edge of display area 501, respectively. Here, the width and height of inspection image 500 are represented by w (w pixels, or w pieces) and h (h pixels, or h pieces), respectively.

[0018] Furthermore, in this embodiment, the display area 501 is rectangular, and the area detection device 103 scans a plurality of lines 502 to 505 set for each of the four sides that form the outer edge of the display area 501. However, this is not a limitation, and a plurality of lines to be scanned for each of the sides that form the outer edge of the display area 501 is set according to the shape of the display area 501. Furthermore, the area detection device 103 scans the plurality of lines 502 to 505 in the inspection image 500 from the outside of the display area 501 toward the display area 501. More specifically, the area detection device 103 will be described as scanning the plurality of lines 502 to 505 from pixels arranged at the edge of the inspection image 500 toward the display area 501. However, this is not a limitation, and the area detection device 103 may scan from the center (or center) of the inspection image 500, where the display area 501 is expected to be located, toward the edge.

[0019] In defect inspection, the display area 501 is typically captured so as to be positioned at the center of the angle of view of the inspection image 500. Furthermore, it is believed that light emission is stable near the center of the display area 501 in both the vertical and horizontal directions. Therefore, scanning the center of the inspection image 500 in both the vertical and horizontal directions is considered appropriate for detecting the display area 501. Therefore, the central pixel of the inspection image 500 in the direction along the edge of the display area 501 to be detected may be located within a range where multiple lines 502-505 are arranged in the direction along the edge of the display area 501 to be detected. Here, the central pixel is a pixel expressed at positions w / 2+0.5 and h / 2+0.5 when w and h are odd numbers. Furthermore, when w and h are even numbers, the central pixel may be a pixel expressed at positions w / 2 and h / 2, or a pixel expressed at positions w / 2+1 and h / 2+1, or both. Furthermore, the center line (indicated by D[0] in FIG. 5) of the multiple lines 502-505 may be formed by the center pixel. When the multiple lines 502-505 are odd-numbered as shown in FIG. 5, the center line of the multiple lines 502-505 is determined to be one line, similar to the center pixel. When the multiple lines 502-505 are even-numbered, the center line of the multiple lines 502-505 may be the two central lines, or one of them. In FIG. 5, the centers in the x and y directions are y=w / 2 and x=h / 2, respectively.

[0020] The threshold value used by the comparators 302 to 306 to compare with the pixel value of the image data of each line may be set according to the pixel value of a pixel located at the center of the inspection image 500. Furthermore, for example, the defect inspection device 100 may perform defect inspections on multiple display devices 107 of the same type. In this case, the threshold value may be set according to the pixel value of a pixel located at the center of the multiple inspection images 500. The central pixel of the inspection image 500 may be, for example, a pixel within a range of 5% or 10% of the pixels between the center position and the edge of the inspection image 500, from the center position toward the edge. The threshold value may be set to a value lower than the luminance of the central region of the inspection image 500, where the illuminated display region 501 of the inspection image 500 is assumed to be captured. For example, the image acquisition unit 101 or the region detection device 103 may set the threshold value according to the luminance of the center of the inspection image 500. Furthermore, for example, a user may visually extract the luminance of the display region 501 displayed in the inspection image 500 and set a lower level as the threshold value.

[0021] Next, we will explain the detection of the coordinate position xstart of the leftmost side that forms the outer edge of the display area 501, which is performed by the area detection device 103, as shown in S202 of Fig. 2. Scanning is performed in the +x direction from x=0. In addition, the y coordinate of D[0], which indicates the center line of the multiple lines 502 to be scanned, is set to h / 2.

[0022] First, image data P[x,h / 2-2], P[x,h / 2-1], P[x,h / 2], P[x,h / 2+1], and P[x,h / 2+2] for five adjacent lines are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. Each of the comparators 302 to 306 compares the pixel values ​​of pixels included in multiple lines 502 with a threshold value. The comparison results of the comparators 302 to 306 are input to an AND circuit 308. The AND circuit 308 outputs "1" when all of the comparators 302 to 306 output "1" (all pixel values ​​of the five lines are equal to or greater than the threshold value). The coordinate acquisition unit 309 acquires the x-coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position xstart. In other words, the position in the scanning direction where all pixel values ​​of the multiple lines 502 change from less than the threshold to greater than or equal to the threshold is detected as the coordinate position xstart. At this time, the output "1" of the AND circuit 308 is notified to the memory control unit 301 as an acquisition end signal for the coordinate position xstart. Upon receiving the acquisition end signal, the memory control unit 301 proceeds to the detection step of the coordinate position xend in S203.

[0023] 2, the coordinate position xend of the right-most side that forms the outer edge of the display area 501 is detected by scanning in the -x direction from x=w-1. Other operations are the same as those for detecting the coordinate position xstart, and the coordinate acquisition unit 309 acquires the x coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position xend. At that time, the output "1" of the AND circuit 308 is notified to the memory control unit 301 as an acquisition end signal for the coordinate position xstart. Upon receiving the acquisition end signal, the memory control unit 301 proceeds to the detection step of the coordinate position ystart in S204.

[0024] Next, we will explain the detection of the coordinate position ystrat of the top edge that forms the outer edge of the display area 501, which is performed by the area detection device 103, as shown in S204 in Figure 2. Scanning is performed in the +y direction from y = 0. In addition, the x coordinate of D[0], which indicates the center line of the multiple lines 504 to be scanned, is set to w / 2.

[0025] First, image data P[w / 2-2,y], P[w / 2-1,y], P[w / 2,y], P[w / 2+1,y], and P[w / 2+2,y] for five adjacent lines are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The comparison results of the comparators 302 to 306 are input to an AND circuit 308. The AND circuit 308 outputs "1" when all the outputs of the comparators 302 to 306 become "1" (all pixel values ​​of the five lines are equal to or greater than the threshold value). The coordinate acquisition unit 309 acquires the y-coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position ystart. At this time, the output "1" of the AND circuit 308 is notified as an acquisition end signal for the coordinate position ystart to the memory control unit 301. Upon receiving the acquisition end signal, the memory control unit 301 proceeds to the detection step of the coordinate position yend in S205.

[0026] 2, the coordinate position yend of the bottom edge that forms the outer edge of the display area 501 is detected by scanning from y=h-1 in the -y direction. Other operations are the same as those for detecting the coordinate position ystart, and the coordinate acquisition unit 309 acquires the y coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position yend. At that time, the output "1" of the AND circuit 308 is notified to the memory control unit 301 as an acquisition end signal for the coordinate position yend. Upon receiving the acquisition end signal, the memory control unit 301 ends detection of the coordinate positions of the display area 501.

[0027] 2, the coordinate positions xstart, xend, ystart, and yend of the display area 501 detected by the area detection device 103 are sent from the area detection device 103 to the defect inspection unit 105. The area detection device 103 may, for example, supply the values ​​of the coordinate positions xstart, xend, ystart, and yend corresponding to each side that constitutes the outer edge of the display area 501 to the defect inspection unit 105. Furthermore, for example, the area detection device 103 may supply the coordinates (xstart, ystart), (xend, ystart), (xstart, yend), and (xend, yend) of the four corners of the display area 501 to the defect inspection unit 105.

[0028] As described above, the area detection device 103 scans the multiple lines 502 to 505 to detect the coordinate positions of each side that forms the outer edge of the display area 501. As a result, even if the inspection image 500 obtained by the image acquisition unit 101 contains a defect 400 caused by the sensor panel of the image acquisition unit 101, it is possible to suppress the influence of the defect 400 and extract the inspection area (display area 501) of the display device 107. In other words, the accuracy of detection of the display area 501 is improved.

[0029] Furthermore, when detecting the coordinate positions of each side constituting the outer edge of the display area 501, it is conceivable to scan the entire inspection image 500. However, as the sensor panel of the image acquisition unit 101 for acquiring the inspection image 500 becomes larger and has more pixels, the number of pixels to be scanned increases, resulting in an increase in the amount of calculations. On the other hand, the area detection device 103 of this embodiment detects one side by scanning a small number of lines, such as five lines. Therefore, even if the sensor panel of the image acquisition unit 101 becomes larger and has more pixels, it is possible to detect the display area 501 of the display device 107 while suppressing an increase in the amount of calculations and suppressing false detection of defects 400.

[0030] In the above embodiment, an example has been shown in which scanning is performed from the edge to the center of the inspection image 500. However, scanning may also be performed from the center (or center) of the inspection image 500 to the edge. In this case, when the output of the AND circuit changes from "1" to "0," each coordinate position is acquired.

[0031] Next, modifications of the above-described defect inspection apparatus 100 and area detection apparatus 103 will be described using FIGS. 6 to 9. FIG. 6 is a diagram showing a modification of the above-described defect inspection apparatus 100. In the above-described embodiment, in the area detection apparatus 103, adjacent lines of the plurality of lines 502 to 505 are each composed of pixels arranged adjacent to each other in a direction along the edge of the detection object. However, this is not limited thereto, and pixels that do not constitute the plurality of lines 502 to 505 may be arranged between adjacent lines of the plurality of lines 502 to 505 in a direction along the edge of the detection object. The configuration shown in FIG. 6 corresponds to a case where there are adjacent defects caused by the sensor panel of the image acquisition unit 101, etc., and scans a wider area in a direction along the edge of the detection object than in the above-described embodiment.

[0032] As shown in FIG. 6, the defect inspection apparatus 100 may have the same configuration as that shown in FIG. 1, except that a signal specifying the line spacing between adjacent lines is input to the area detection device 103. FIG. 7 is a diagram showing an example configuration of the area detection device 103 of this embodiment. As shown in FIG. 7, the area detection device 103 may have the same configuration as that shown in FIG. 3, except that the line spacing d is input to the memory control unit 301. For example, if "1" is input as the line spacing d, each of the multiple lines 502 to 505 adjacent to each other is composed of pixels arranged adjacent to each other in a direction along the edge of the detection target. In other words, the area detection device 103 operates in the same manner as the above-described embodiment. Therefore, differences from the above-described configuration will be mainly described, and descriptions of configurations that may be similar will be omitted as appropriate. For example, the processing flow of the defect inspection apparatus 100 may be the same as the processing flow shown in FIG. 2.

[0033] The area detection device 103 shown in Fig. 7 is effective when multiple defects 800, 801 appear close to each other in the inspection image 500, as shown in Fig. 8. For example, as shown in Fig. 8, the area detection device 103 scans lines of five pixels at a line spacing d (d=2 in the case of Fig. 8) that is larger than the line spacing shown in Fig. 4, so as to avoid erroneous detection of defects 800, 801 of six pixels. As a result, the width scanned by the area detection device 103 in the direction along the edge of the detection target is 10 pixels, which suppresses erroneous detection of defects 800, 801 and improves the detection accuracy of the coordinate positions of the edges that form the outer edge of the display area 501.

[0034] Next, the operation of the area detection device 103 of this embodiment will be described with reference to Fig. 9. Here, explanations of configurations that may be similar to the configuration shown in Fig. 5 will be omitted as appropriate. As in the operation of the above-described embodiment, the memory control unit 301 is provided with information (w, h) about the width and height of the inspection image 500. Also, here, as in the flow shown in Fig. 2, the coordinates of each side that constitutes the outer edge of the display area 501 are detected in the order of coordinate position xstart, coordinate position xend, coordinate position ystart, and coordinate position yend.

[0035] 9 are five lines scanned to detect the coordinate position xstart of the left-most side that constitutes the outer edge of the display area 501. Similarly, multiple lines 901, 902, and 903 are five lines scanned to detect the coordinate position xend of the right-most side, the coordinate position ystart of the top-most side, and the coordinate position yend of the bottom-most side that constitute the outer edge of the display area 501. Here, as in the above-described embodiment, the centers in the x and y directions are set to y=w / 2 and x=h / 2, respectively.

[0036] First, we will explain the detection of the coordinate position xstart of the leftmost side that forms the outer edge of the display area 501, which is performed by the area detection device 103, as shown in S202 in Figure 2. Scanning is performed in the +x direction from x=0. Furthermore, the y coordinate of D[0], which indicates the center line of the multiple lines 900 to be scanned, is set to h / 2.

[0037] Image data P[x,h / 2-2d], P[x,h / 2-d], P[x,h / 2], P[x,h / 2+d], and P[x,h / 2+2d] for five lines with a set line spacing d are read from the image memory 102 via the memory control unit 301. The line spacing d may be set by inputting an appropriate value by the user. Alternatively, data for setting the line spacing d may be sent to the area detection device 103 from a storage unit (e.g., the image memory 102) that stores the size of defects appearing in the inspection image 500 according to the characteristics of the image acquisition unit 101. The image data P is input to the comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The subsequent operation may be the same as that described with reference to FIG. 5, and the coordinate acquisition unit 309 acquires the x-coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position xstart. At this time, the output "1" of the AND circuit 308 is notified as an acquisition end signal for the coordinate position xstart to the memory control unit 301. Upon receiving the acquisition end signal, the memory control unit 301 proceeds to the detection step of the coordinate position xend in S203.

[0038] 2, the coordinate position xend of the right-most side that forms the outer edge of the display area 501 is detected by scanning in the -x direction from x=w-1. Other operations are the same as those for detecting the coordinate position xstart, and the coordinate acquisition unit 309 acquires the x coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position xend. At that time, the output "1" of the AND circuit 308 is notified to the memory control unit 301 as an acquisition end signal for the coordinate position xstart. Upon receiving the acquisition end signal, the memory control unit 301 proceeds to the detection step of the coordinate position ystart in S204.

[0039] Next, we will explain the detection of the coordinate position ystrat of the top edge that forms the outer edge of the display area 501, which is performed by the area detection device 103 in S204 of Fig. 2. Scanning is performed in the +y direction from y=0. In addition, the x coordinate of D[0], which indicates the center line of the multiple lines 504 to be scanned, is set to w / 2. First, image data P[w / 2-2d,y], P[w / 2-d,y], P[w / 2,y], P[w / 2+d,y], and P[w / 2+2d,y] for five lines spaced apart by a line interval d are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. Subsequent operations are similar to those described with reference to FIG. 5, and the coordinate acquisition unit 309 acquires the y-coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position ystart. At this time, the output "1" of the AND circuit 308 is notified to the memory control unit 301 as an acquisition end signal for the coordinate position ystart. Upon receiving the acquisition end signal, the memory control unit 301 proceeds to the step of detecting the coordinate position yend in S205.

[0040] 2, the coordinate position yend of the bottom edge that forms the outer edge of the display area 501 is detected by scanning from y=h-1 in the -y direction. Other operations are the same as those for detecting the coordinate position ystart, and the coordinate acquisition unit 309 acquires the y coordinate value when the output of the AND circuit 308 changes from "0" to "1" as the coordinate position yend. At that time, the output "1" of the AND circuit 308 is notified to the memory control unit 301 as an acquisition end signal for the coordinate position yend. Upon receiving the acquisition end signal, the memory control unit 301 ends detection of the coordinate positions of the display area 501.

[0041] 2, the coordinate positions xstart, xend, ystart, and yend of the display area 501 detected by the area detection device 103 are sent from the area detection device 103 to the defect inspection unit 105. The area detection device 103 may, for example, supply the values ​​of the coordinate positions xstart, xend, ystart, and yend corresponding to each side that constitutes the outer edge of the display area 501 to the defect inspection unit 105. Furthermore, for example, the area detection device 103 may supply the coordinates (xstart, ystart), (xend, ystart), (xstart, yend), and (xend, yend) of the four corners of the display area 501 to the defect inspection unit 105.

[0042] 6 to 9, the area detection device 103 scans the multiple lines 502 to 505 at a predetermined line interval d to detect the coordinate position of each side that forms the outer edge of the display area 501. This makes it possible to suppress the influence of defects even when the inspection image 500 obtained by the image acquisition unit 101 contains a defect larger than the defect 400 (FIG. 4) caused by the sensor panel of the image acquisition unit 101 or when multiple defects such as the defects 800 and 801 are lined up. In other words, the accuracy of detecting the inspection area (display area 501) of the display device 107 is improved.

[0043] The line spacing d may be 2 as described above, or may be 3 or more. It can be changed as appropriate depending on the characteristics of the sensor panel of the image acquisition unit 101. In each of the above-described embodiments, the center position of the line scanned to detect the coordinate positions xstart and xend is set to y=h / 2, and the center position of the line scanned to detect the coordinate positions ystart and yend is set to x=w / 2. However, this is not limited thereto, and the lines may be set at any positions as long as a level of brightness sufficient to acquire the coordinate positions of the display area 501 is ensured. For example, the center line of the multiple lines 502 to 505 and 900 to 903 may be appropriately selected depending on the pixel values ​​of the display area 501 of the display device 107.

[0044] Next, modified examples of the defect inspection apparatus 100 and area detection apparatus 103 described above will be described with reference to FIGS. 10 to 17. This embodiment includes error processing (stopping inspection) when the display area 501 of the display device 107 cannot be properly detected from the inspection image 500 acquired by the image acquisition unit 101. Specifically, the area detection apparatus 103 processes the inspection image 500 as an error image when the coordinate positions of the sides constituting the outer edge of the detected display area 501 are not within a predetermined valid coordinate area. Furthermore, in this embodiment, the center positions of the lines scanned to detect the coordinate positions xstart and xend and the center positions of the lines scanned to detect the coordinate positions ystart and yend can be set to any positions. For example, the center positions of the lines scanned to detect the coordinate positions xstart, xend, ystart, and yend may be set to appropriate positions depending on the pixel values ​​of the display area 501. The center position of the line may be specified by the user with reference to the inspection image 500, or may be automatically determined by a processing circuit (not shown) arranged in the defect inspection device 100 or the area detection device 103 with reference to the inspection image 500.

[0045] In addition to the thresholds used in the comparators 302 to 306, the following settings are input to the area detection device 103. The line spacing x sets the spacing between adjacent lines among the multiple lines when detecting the coordinate positions ystart and yend. The line spacing y sets the spacing between adjacent lines among the multiple lines when detecting the coordinate positions xstart and xend. The setting x_pos sets the x-direction position of the center line among the multiple lines when detecting the coordinate positions ystart and yend. The setting x_pos_d sets the number (number of pixels) by which the positions of the multiple lines are shifted in a direction along the target side when the detected coordinate positions ystart and yend are not within a preset range, as will be described later. The setting y_pos sets the y-direction position of the center line among the multiple lines when detecting the coordinate positions xstart and xend. The setting y_pos_d sets the number (number of pixels) by which the positions of the multiple lines are shifted in a direction along the target side when the detected coordinate positions xstart and xend are not within a preset range when detecting the coordinate positions xstart and xend. The setting xs_base sets the valid coordinate area for the coordinate position xstart. The setting xe_base sets the center coordinate of the valid coordinate area for the coordinate position xend. The setting ys_base sets the center coordinate of the valid coordinate area for the coordinate position ystart. The setting ye_base sets the center coordinate of the valid coordinate area for the coordinate position yend. The settings x_base_d and ybase_d set the range of the valid coordinate area from the center coordinate set by the settings xs_base, xe_base, ys_base, and ye_base. The setting retry_max sets the maximum number of times the positions of multiple lines are shifted in the direction along the target edge if the detected coordinate position is not within the range of the preset valid coordinate area. In addition, the area detection device 103 performs error processing if the coordinate positions of the edges constituting the outer edge of the detected display area 501 are not within the range of the preset valid coordinate area. In other words, if the display area 501 of the display device 107 cannot be properly detected from the inspection image 500, an interruption notification abort indicating that scanning has been stopped is output.

[0046] FIG. 11 shows the processing flow of the defect inspection apparatus 100 shown in FIG. 10. Steps S201 and S202 are the same as those described with reference to FIG. 2. Next, in step S1100, the area detection device 103 reads image data for scanning pixel values ​​from the pixel located at the left edge of the inspection image 500 from the image memory 102 and detects the coordinate position xstart of the left edge side that forms the outer edge of the display area 501. If the coordinate position xstart is detected correctly (the coordinate position xstart is within the range of the valid coordinate area set by the settings xs_base and x_base_d), the processing proceeds to step S1101. On the other hand, if the detected coordinate position xstart is not within the range of the valid coordinate area previously set by the settings xs_base and x_base_d, the area detection device 103 shifts the positions of the multiple lines to be scanned in accordance with the setting y_pos_d. Next, the multiple lines are scanned again to detect the coordinate position xstart. If the detected coordinate position xstart is not within a preset valid coordinate area, the area detection device 103 repeatedly shifts the position of the multiple lines and scans the multiple lines. If the coordinate position xstart is not within the preset valid coordinate area after repeating the process a predetermined number of times set by the setting retry_max, the area detection device 103 determines that the coordinate position xstart is not detectable and stops scanning the multiple lines. This causes the defect inspection device 100 to end the inspection.

[0047] If the coordinate position xstart is detected successfully, in S1101, the area detection device 103 reads image data from the image memory 102 to scan pixel values ​​from pixels located at the right edge of the inspection image 500, and detects the coordinate position xend of the right edge that forms the outer edge of the display area 501. If the coordinate position xend is detected successfully (the coordinate position xend is within the range of the valid coordinate area set by the settings xe_base and x_base_d), the process proceeds to S1102. On the other hand, if the detected coordinate position xend is not within the range of the valid coordinate area previously set by the settings xe_base and x_base_d, the area detection device 103 shifts the positions of the multiple lines to be scanned according to the setting y_pos_d. Next, the area detection device 103 scans the multiple lines again. As with the detection of the coordinate position xstart, if the detected coordinate position xend is not within the range of the previously set valid coordinate area, the area detection device 103 repeats shifting the positions of the multiple lines and scanning the multiple lines. If the coordinate position xend is not within the range of the preset valid coordinate area after repeating the predetermined number of times set by the setting retry_max, the area detection device 103 determines that the coordinate position xend is not detectable and stops scanning the multiple lines. This causes the defect inspection device 100 to end the inspection.

[0048] If the coordinate position xend is successfully detected, in S1102, the area detection device 103 reads image data from the image memory 102 to scan pixel values ​​from pixels located at the top of the inspection image 500, and detects the coordinate position ystart of the top edge that forms the outer edge of the display area 501. If the coordinate position ystart is successfully detected (the coordinate position ystart is within the range of the valid coordinate area set by the settings ys_base and y_base_d), the process proceeds to S1103. On the other hand, if the detected coordinate position ystart is not within the range of the valid coordinate area previously set by the settings ys_base and y_base_d, the area detection device 103 shifts the positions of the multiple lines to be scanned according to the setting x_pos_d. Next, the area detection device 103 scans the multiple lines again. As with the detection of the coordinate positions xstart and xend, if the detected coordinate position ystart is not within the range of the valid coordinate area previously set, the area detection device 103 repeats shifting the positions of the multiple lines and scanning the multiple lines. If the coordinate position ystart is not within the range of the preset valid coordinate area after repeating the predetermined number of times set by the setting retry_max, the area detection device 103 determines that the coordinate position ystart is undetectable and stops scanning the multiple lines. This causes the defect inspection device 100 to end the inspection.

[0049] If the coordinate position ystart is successfully detected, in S1103, the area detection device 103 reads image data from the image memory 102 to scan pixel values ​​from pixels located at the bottom of the inspection image 500, and detects the coordinate position yend of the bottom edge that forms the outer edge of the display area 501. If the coordinate position yend is successfully detected (the coordinate position yend is within the range of the effective coordinate area set by the settings ye_base and y_base_d), processing proceeds to S206. On the other hand, if the detected coordinate position yend is not within the range of the effective coordinate area previously set by the settings ye_base and y_base_d, the area detection device 103 shifts the positions of the multiple lines to be scanned according to the setting x_pos_d. Next, the area detection device 103 scans the multiple lines again. As with the detection of the coordinate positions xstart, xend, and ystart, if the detected coordinate position yend is not within the range of the effective coordinate area previously set, the area detection device 103 repeats shifting the positions of the multiple lines and scanning the multiple lines. If the coordinate position Y end is not within the range of the preset valid coordinate area after repeating the predetermined number of times set by the setting retry_max, the area detection device 103 determines that the coordinate position Y end is undetectable and stops scanning the multiple lines. This causes the defect inspection device 100 to end the inspection.

[0050] When the respective coordinate positions xstart, ystart, xend, and yend are detected, in S206, the coordinate positions xstart, ystart, xend, and ystart of each side of the detected display area 501 are output from the area detection device 103 to the defect inspection unit 105. The area detection device 103 detects the coordinate positions of each side that constitutes the outer edge of the display area 501, thereby identifying the display area 501 from the inspection image 500. In S207, the defect inspection unit 105 performs an operation to detect defects in the display area 501 identified by the area detection device 103.

[0051] Next, the configuration of the area detection device 103 of this embodiment will be described with reference to Fig. 12. Configurations that differ from the configurations shown in Fig. 3 and Fig. 7 will be described, and descriptions of configurations that may be similar will be omitted as appropriate.

[0052] The line interval x and the line interval y are input to the memory control unit 301. Furthermore, the memory control unit 301 also receives the settings x_pos, x_pos_d, y_pos, and y_pos_d.

[0053] A signal 1207 propagates the address of the pixel being scanned from the memory control unit 301 to an address determination unit 1209 (described later) and a coordinate acquisition unit 309. A signal 1208 notifies a rescan from the address determination unit 1209. A signal 1218 notifies the address determination unit 1209 that the coordinate positions xstart, xend, ystart, and yend have been detected.

[0054] The settings xs_base, xe_base, ys_base, ye_base, x_base_d, y_base_d, and retry_max are input to the address determination unit 1209. Furthermore, if the display area 501 of the display device 107 cannot be properly detected from the inspection image 500, the address determination unit 1209 outputs an interruption notification abort indicating that scanning has been stopped.

[0055] Next, the operation of the area detection device 103 of this embodiment will be described with reference to Fig. 13. Here, explanation of configurations that may be similar to the configuration shown in Fig. 5 will be omitted as appropriate. As in the operation of the above-described embodiment, the memory control unit 301 is provided with width and height information (w, h) of the inspection image 500. Also, here, as in the flow shown in Fig. 11, the coordinates of each side that constitutes the outer edge of the display area 501 are detected in the order of coordinate position xstart, coordinate position xend, coordinate position ystart, and coordinate position yend. In the operation shown in Fig. 13, the line spacing x is set to xd, and the line spacing x input terminal 1202 is set to yd.

[0056] The multiple lines 1300 are five lines scanned to detect the coordinate position xstart of the leftmost side that constitutes the outer edge of the display area 501. Similarly, the multiple lines 1301, 1302, and 1303 are five lines scanned to detect the coordinate position xend of the rightmost side, the coordinate position ystart of the topmost side, and the coordinate position yend of the bottommost side that constitute the outer edge of the display area 501, respectively.

[0057] First, a description will be given of detection of the coordinate position xstart of the left edge that forms the outer edge of the display area 501, which is performed by the area detection device 103, as shown in S1100 in Fig. 11. Fig. 14 is a detailed flowchart showing the processing in S1100.

[0058] When the process transitions from S201 to S1400 (S1100), the position at which to start scanning the multiple lines 1300 is set. The setting y_pos sets the y coordinate of D[0], which indicates the center line of the multiple lines 1300 to be scanned, to y_pos. Also, an x-direction counter indicating the position in the x-direction in the memory control unit 301 is set to 0, and a rescan counter retry in the address determination unit 1209 is set to 0.

[0059] Next, in each step from S1401, scanning is performed from the left edge of the inspection image 500 in the +x direction. Specifically, five lines of image data P[x,y_pos+y_pos_d*retry-2yd], P[x,y_pos+y_pos_d*retry-yd], P[x,y_pos+y_pos_d*retry], P[x,y_pos+y_pos_d*retry+yd], and P[x,y_pos+y_pos_d*retry+2yd] are read from the image memory 102 via the memory control unit 301. The image data P is input to the comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The image data P is compared with a threshold set in each of the comparators 302 to 306, and the comparison result is input to the AND circuit 308.

[0060] Next, in S1402, it is determined whether the coordinate position xstart has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all comparators 302 to 306 are "1" (whether the pixel values ​​of all five lines are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the x-direction counter is incremented by +1 in S1403, and the process returns to S1401, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the +x direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1404.

[0061] In S1404, the address determination unit 1209 determines whether the coordinate position xstart is within the range of the valid coordinate area preset by the settings xs_base and x_base_d. Specifically, it determines whether the coordinate position xstart is within the range of xs_base±x_base_d. If the coordinate position xstart is greater than xs_base+x_base_d or smaller than xs_base-x_base_d (Yes in S1404), the coordinate position xstart is not within the range of the valid coordinate area, and the process proceeds to S1405.

[0062] In S1405, the rescan counter "retry" is incremented by +1, a rescan is notified to the memory control unit 301 by a signal 1208, and processing proceeds to S1406. In S1406, the address determination unit 1209 determines whether the value of the rescan counter "retry" is greater than the set value "retry_max." If the value of the rescan counter "retry" is greater than the set value "retry_max," it is determined that there is a defect in the inspection image 500 and the coordinate position xstart cannot be detected, and an interruption notification "abort" is output from the address determination unit 1209, and the defect inspection apparatus 100 ends the inspection. If the value of the rescan counter "retry" is smaller than the set value "retry_max," processing proceeds to S1407.

[0063] In S1407, the memory control unit 301 shifts the y coordinate of D[0], which indicates the center line of the multiple lines 1300 to be scanned, to a position calculated by y_pos+y_pos_d*retry. Also, the x-direction counter is reset to "0" by signal 1208. Then, the process proceeds to S1402, and the above steps are repeated.

[0064] Furthermore, in S1404, if the coordinate position xstart is within the range of xs_base±x_base_d (No in S1404), the coordinate position xstart is within the range of the valid coordinate area, and therefore the coordinate position xstart is determined (S1408). In other words, it is determined that the coordinate position xstart has been detected. In this case, the signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position xstart is stored. The signal 1218 is also supplied to the memory control unit 301, and the memory control unit 301 proceeds to the step of detecting the coordinate position xend in S1101.

[0065] Next, the detection of the coordinate position xend of the right-most side constituting the outer edge of the display area 501, which is performed by the area detection device 103 in S1101 of Fig. 11, will be described. Fig. 15 is a detailed flow diagram showing the processing in S1101. Explanations of steps similar to those in the detection flow of the coordinate position xstart described using Fig. 14 will be omitted where appropriate.

[0066] When the process transitions from S1506 (S1100) to S1500 (S1101), the position where scanning of the multiple lines 1301 starts is set. The setting y_pos sets the y coordinate of D[0], which indicates the center line of the multiple lines 1300 to be scanned, to y_pos. Also, the x-direction counter indicating the x-direction position in the memory control unit 301 is set to w-1 (the x-coordinate of the right edge of the inspection image 500), and the rescan counter retry in the address determination unit 1209 is set to 0.

[0067] Next, in each step from S1501, scanning is performed in the −x direction from the right edge of the inspection image 500. Specifically, five lines of image data P[x,y_pos+y_pos_d*retry-2yd], P[x,y_pos+y_pos_d*retry-yd], P[x,y_pos+y_pos_d*retry], P[x,y_pos+y_pos_d*retry+yd], and P[x,pos+y_pos_d*retry+2yd] are read from the image memory 102 via the memory control unit 301. The image data P is input to the comparators 302 to 306 via D[−2], D[−1], D[0], D[1], and D[2], respectively. The image data P is compared with a threshold set in each of the comparators 302 to 306, and the comparison result is input to the AND circuit 308.

[0068] Next, in S1502, it is determined whether the coordinate position xend has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all comparators 302 to 306 are "1" (whether the pixel values ​​of all five lines are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the x-direction counter is decremented by -1 in S1503, and the process returns to S1501, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the -x direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1504.

[0069] In S1504, the address determination unit 1209 determines whether the coordinate position xend is within the range of the valid coordinate area preset by the settings xe_base and x_base_d. Specifically, it determines whether the coordinate position xend is within the range of xe_base±x_base_d. If the coordinate position xend is greater than xe_base+x_base_d or smaller than xe_base-x_base_d (Yes in S1504), the coordinate position xend is not within the range of the valid coordinate area, and the process proceeds to S1405 and S1406.

[0070] S1405 and S1406 are the same as the flow for detecting the coordinate position xstart described above. In S1406, if the value of the rescan counter retry is greater than the setting retry_max, it is determined that there is a defect in the inspection image 500 and the coordinate position xend cannot be detected, so an interruption notification abort is output from the address determination unit 1209 and the defect inspection apparatus 100 ends the inspection. On the other hand, if the value of the rescan counter retry is smaller than the setting retry_max, the process proceeds to S1505.

[0071] In S1505, the memory control unit 301 shifts the y coordinate of D[0], which indicates the center line of the multiple lines 1301 to be scanned, to a position calculated by y_pos+y_pos_d*retry. Also, the x-direction counter is reset to "w-1" by signal 1208. Then, the process proceeds to S1501, and the above steps are repeated.

[0072] Furthermore, in S1504, if the coordinate position xend is within the range of xe_base±x_base_d (No in S1504), the coordinate position xend is within the range of the valid coordinate area, and therefore the coordinate position xend is determined (S1506). In other words, it is determined that the coordinate position xend has been detected. In this case, signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position xend is stored. Signal 1218 is also supplied to the memory control unit 301, and the memory control unit 301 proceeds to the step of detecting the coordinate position ystart in S1102.

[0073] Next, the detection of the coordinate position ystart of the top edge that forms the outer edge of the display area 501, which is performed by the area detection device 103 in S1102 of Fig. 11, will be described. Fig. 16 is a detailed flow diagram showing the processing in S1102. Explanations of steps similar to those in the detection flow for the coordinate positions xstart and xend described using Figs. 14 and 15 will be omitted where appropriate.

[0074] When the process transitions from S1506 (S1101) to S1600 (S1102), the position at which to start scanning the multiple lines 1302 is set. The setting x_pos sets the x coordinate of D[0], which indicates the center line of the multiple lines 1302 to be scanned, to x_pos. Also, the y-direction counter indicating the position in the y direction in the memory control unit 301 and the rescan counter retry in the address determination unit 1209 are set to 0, respectively.

[0075] Next, in each step from S1601, scanning is performed from the top edge of the inspection image 500 in the +y direction. Specifically, five lines of image data P[x_pos+x_pos_d*retry-2xd,y], P[x_pos+x_pos_d*retry-xd,y], P[x_pos+x_pos_d*retry,y], P[x_pos+x_pos_d*retry+xd,y], and P[x_pos+x_pos_d*retry+2xd,y] are read from the image memory 102 via the memory control unit 301. The image data P is input to the comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The image data P is compared with a threshold set in each of the comparators 302 to 306, and the comparison result is input to the AND circuit 308.

[0076] Next, in S1602, it is determined whether the coordinate position ystart has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all comparators 302 to 306 are "1" (whether the pixel values ​​of all five lines are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the y-direction counter is incremented by +1 in S1603, and the process returns to S1601, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the +y direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1604.

[0077] In S1604, the address determination unit 1209 determines whether the coordinate position ystart is within the range of the valid coordinate area preset by the settings ys_base and y_base_d. Specifically, it determines whether the coordinate position ystart is within the range of ys_base±y_base_d. If the coordinate position ystart is greater than ys_base+y_base_d or smaller than ys_base−y_base_d (Yes in S1604), the coordinate position ystart is not within the range of the valid coordinate area, and the process proceeds to S1405 and S1406.

[0078] In S1406, if the value of the rescan counter "retry" is greater than the setting "retry_max," it is determined that there is a defect in the inspection image 500 and the coordinate position ystart cannot be detected, and an interruption notification "abort" is output from the address determination unit 1209, and the defect inspection apparatus 100 terminates the inspection. On the other hand, if the value of the rescan counter "retry" is smaller than the setting "retry_max," the process proceeds to S1605.

[0079] In S1605, the memory control unit 301 shifts the x coordinate of D[0], which indicates the center line of the multiple lines 1302 to be scanned, to a position calculated by x_pos+x_pos_d*retry. Also, the y-direction counter is reset to "0" by signal 1208. Then, the process proceeds to S1601, and the above steps are repeated.

[0080] Furthermore, in S1604, if the coordinate position ystart is within the range of ys_base±y_base_d (No in S1604), the coordinate position ystart is within the range of the valid coordinate area, and therefore the coordinate position ystart is determined (S1606). In other words, it is determined that the coordinate position ystart has been detected. In this case, a signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position ystart is stored. The signal 1218 is also supplied to the memory control unit 301, and the memory control unit 301 proceeds to the step of detecting the coordinate position yend in S1103.

[0081] Next, the detection of the coordinate position yend of the bottom edge that forms the outer edge of the display area 501, which is performed by the area detection device 103 in S1103 of Fig. 11, will be described. Fig. 17 is a detailed flow diagram showing the processing in S1102. Explanations of steps similar to those in the detection flow for the coordinate positions xstart, xend, and ystart described using Figs. 14 to 16 will be omitted where appropriate.

[0082] When the process transitions from S1606 (S1102) to S1700 (S1103), the position at which to start scanning the multiple lines 1303 is set. The setting x_pos sets the x coordinate of D[0], which indicates the center line of the multiple lines 1303 to be scanned, to x_pos. Also, the y-direction counter indicating the position in the y direction in the memory control unit 301 is set to h-1 (the y coordinate of the bottom edge of the inspection image 500), and the rescan counter retry in the address determination unit 1209 is set to 0.

[0083] Next, in each step from S1701, scanning is performed from the bottom edge of the inspection image 500 in the -y direction. Specifically, five lines of image data P[x_pos+x_pos_d*retry-2xd,y], P[x_pos+x_pos_d*retry-xd,y], P[x_pos+x_pos_d*retry,y], P[x_pos+x_pos_d*retry+xd,y], and P[x_pos+x_pos_d*retry+2xd,y] are read from the image memory 102 via the memory control unit 301. The image data P is input to the comparators 302 to 306 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The image data P is compared with a threshold set in each of the comparators 302 to 306, and the comparison result is input to the AND circuit 308.

[0084] Next, in S1702, it is determined whether the coordinate position yend has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all comparators 302 to 306 are "1" (whether the pixel values ​​of all five lines are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the y-direction counter is decremented by -1 in S1603, and the process returns to S1701, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the -y direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1704.

[0085] In S1704, the address determination unit 1209 determines whether the coordinate position yend is within the range of the valid coordinate area preset by the settings ye_base and y_base_d. Specifically, it determines whether the coordinate position yend is within the range of ye_base±y_base_d. If the coordinate position yend is greater than ye_base+y_base_d or smaller than ye_base−y_base_d (Yes in S1704), the coordinate position yend is not within the range of the valid coordinate area, and the process proceeds to S1405 and S1406.

[0086] S1405 and S1406 are the same as the flow for detecting the coordinate positions xstart, xend, and ystart described above. In S1406, if the value of the rescan counter "retry" is greater than the setting "retry_max," it is determined that there is a defect in the inspection image 500 and the coordinate position "yend" cannot be detected, and an interruption notification "abort" is output from the address determination unit 1209, and the defect inspection apparatus 100 ends the inspection. Also, if the value of the rescan counter "retry" is smaller than the setting "retry_max," the process proceeds to S1705.

[0087] In S1705, the memory control unit 301 shifts the x coordinate of D[0], which indicates the center line of the multiple lines 1303 to be scanned, to a position calculated by x_pos+x_pos_d*retry. Also, the y-direction counter is reset to "h-1" by signal 1208. Then, the process proceeds to S1701, and the above steps are repeated.

[0088] Furthermore, in S1704, if the coordinate position yend is within the range of ye_base±y_base_d (No in S1704), the coordinate position yend is within the range of the valid coordinate area, and therefore the coordinate position yend is determined (S1706). In other words, it is determined that the coordinate position yend has been detected. In this case, signal 1218 is output from address determination unit 1209 to coordinate acquisition unit 309, and coordinate position yend is stored. Signal 1218 is also supplied to memory control unit 301, and the step of detecting each side that constitutes the outer edge of display area 501 is completed.

[0089] When the coordinate positions xstart, ystart, xend, and yend are detected, in S206, the detected coordinate positions xstart, ystart, xend, and ystart of each side of the display area 501 are output from the area detection device 103 to the defect inspection unit 105. The area detection device 103 may, for example, supply the values ​​of the coordinate positions xstart, xend, ystart, and yend corresponding to each side that constitutes the outer edge of the display area 501 to the defect inspection unit 105. Furthermore, for example, the area detection device 103 may supply the coordinates (xstart, ystart), (xend, ystart), (xstart, yend), and (xend, yend) of the four corners of the display area 501 to the defect inspection unit 105. Next, in S207, the defect inspection unit 105 performs an operation to detect defects in the display area 501 identified by the area detection device 103.

[0090] As described above, when detecting the coordinate positions of each side constituting the outer edge of the display area 501, the area detection device 103 determines whether the coordinate positions are appropriate, and if they are not appropriate, changes the position and scans again. This makes it possible to detect the display area 501 of the display device 107 more reliably than in the above-described embodiment. It also makes it possible to detect defective inspection images 500 before inspection by the defect inspection unit 105. Since inspection by the defect inspection unit 105 generally takes time, a fail-stop that ends inspection before inspection by the defect inspection unit 105 is possible. This makes it possible to shorten the inspection time for the entire inspection lot, such as inspecting multiple display devices 107.

[0091] In this embodiment, the settings x_pos_d and y_pos_d that shift the scanning position may be positive or negative. When the settings x_pos_d and y_pos_d are positive values, the line scanned to detect the sides that form the outer edge of the display area 501 is shifted in the positive direction when the coordinate position is not appropriate. When the settings x_pos_d and y_pos_d are negative values, the line scanned to detect the sides that form the outer edge of the display area 501 is shifted in the negative direction when the coordinate position is not appropriate.

[0092] In addition, in each of the above-described embodiments, the number of lines to be scanned is set to 5. However, this is not limited to this, and the number may be 2 to 4 lines, or 6 or more lines depending on the size and density of the defects 400, 800, 801 caused by the sensor panel of the image acquisition unit 101. For example, the user may change the number of lines to be scanned depending on the lot to be inspected.

[0093] Next, modifications of the defect inspection device 100 and area detection device 103 described above will be described with reference to FIGS. 18 to 24. In this embodiment, as with the area detection device 103 described with reference to FIGS. 10 to 17, error processing (inspection aborted) is performed when the display area 501 of the display device 107 cannot be properly detected from the inspection image 500 acquired by the image acquisition unit 101. However, unlike the area detection device 103 described with reference to FIGS. 10 to 17, when the coordinate positions of the sides constituting the outer edge of the detected display area 501 are not within a preset valid coordinate area, the number of lines for detecting the coordinate positions of the sides is increased. By increasing the number of lines and scanning multiple lines again, the detection accuracy of the display area 501 of the display device 107 is improved.

[0094] 10, the area detection device 103 shown in FIG. 18 does not receive the line spacing x, line spacing y, settings x_pos_d, y_pos_d, and retry_max, but receives the number of scan lines instead. That is, the area detection device 103 shown in FIG. 18 receives the thresholds used in comparators 302 to 306, settings x_pos, y_pos, xs_base, xe_base, ys_base, ye_base, x_base_d, y_base_d, and the number of scan lines. In this embodiment, the processing flow in the area detection device 103 may be similar to the processing flow shown in FIG. 11. Meanwhile, in this embodiment, when the detected coordinate position is not within a predetermined range, the area detection device 103 repeatedly increases the number of lines and scans the multiple lines to detect the display area 501. At this time, if the coordinate position is not within a preset range until a predetermined number of lines is reached, the area detection device 103 stops scanning the multiple lines and outputs an interruption notification "abort" indicating that scanning has been stopped. Here, the predetermined number of lines is the maximum number of lines that the memory control unit 301 can read from the image memory 102.

[0095] Fig. 19 is a diagram showing an example of the configuration of the area detection device 103 of this embodiment. Configurations that differ from the configuration shown in Fig. 12 will be described, and descriptions of configurations that may be similar will be omitted as appropriate.

[0096] The number of scan lines and the settings x_pos and y_pos are input to the memory control unit 301. Here, the memory control unit 301 is capable of reading out image data of up to n+1 lines (n is an even number) from the image memory 102, and is connected to comparators 1902 to 1908 for comparing the read image data of the n+1 lines with a threshold value. The outputs of the comparators 1902 to 1908 are connected to an AND circuit 308.

[0097] Next, the operation of the area detection device 103 of this embodiment will be described with reference to FIG. 20. Here, the description of configurations that may be similar to the configuration shown in FIG. 5 will be omitted as appropriate. As in the operation of the above-described embodiment, the memory control unit 301 is provided with width and height information (w, h) of the inspection image 500. Also, here, as in the flow shown in FIG. 11, the coordinates of each side that constitutes the outer edge of the display area 501 are detected in the order of coordinate position xstart, coordinate position xend, coordinate position ystart, and coordinate position yend. Also, the set x_pos and y_pos are set to the center images of the inspection image 500 in the vertical and horizontal directions, respectively.

[0098] The multiple lines 2000 are n+1 lines scanned to detect the coordinate position xstart of the leftmost side that constitutes the outer edge of the display area 501. Similarly, the multiple lines 2001, 2002, and 2003 are n+1 lines scanned to detect the coordinate position xend of the rightmost side, the coordinate position ystart of the topmost side, and the coordinate position yend of the bottommost side that constitute the outer edge of the display area 501, respectively.

[0099] First, a description will be given of detection of the coordinate position xstart of the left edge that forms the outer edge of the display area 501, which is performed by the area detection device 103, as shown in S1100 in Fig. 11. Fig. 21 is a detailed flowchart showing the processing in S1100.

[0100] When the process transitions from S201 to S2100 (S1100), the position where scanning of the multiple lines 2000 starts is set. The setting y_pos sets the y coordinate of D[0], which indicates the center line of the multiple lines 2000 to be scanned, to y_pos. Also, the x-direction counter, which indicates the position in the x-direction within the memory control unit 301, is set to 0, and the scan line number counter lnum is set to 5.

[0101] Next, in each step from S2101, scanning is performed from the left edge of the inspection image 500 in the +x direction. Specifically, image data P[x,y_pos-2], P[x,y_pos-1], P[x,y_pos], P[x,y_pos+1], and P[x,y_pos+2] for five lines, which is the value of the scan line number counter lnum, are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 1903 to 1907 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The image data P is compared with a threshold set in each of the comparators 1903 to 1907, and the comparison result is input to an AND circuit 308. At this time, the output (D[-n / 2], D[+n / 2], etc.) from the memory control unit 301 of the line not to be scanned is a value greater than the set threshold, and the output of the connected comparator is set to "1." For example, the memory control unit 301 may supply the maximum value of the memory data (8'hFF in the case of 8 bits) to the line not to be scanned.

[0102] Next, in S2102, it is determined whether the coordinate position xstart has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all of the comparators 1902 to 1908 are "1" (whether all pixel values ​​are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the x-direction counter is incremented by +1 in S2103, and the process returns to S2101, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the +x direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1404.

[0103] In S1404, the address determination unit 1209 determines whether the coordinate position xstart is within the range of the valid coordinate area preset by the settings xs_base and x_base_d. Specifically, it determines whether the coordinate position xstart is within the range of xs_base±x_base_d. If the coordinate position xstart is greater than xs_base+x_base_d or smaller than xs_base-x_base_d (Yes in S1404), the coordinate position xstart is not within the range of the valid coordinate area, and the process proceeds to S2104.

[0104] In S2104, the memory control unit 301 is notified of a rescan by a signal 1208, and the scan line number counter lnum is incremented by +2 to increase the number of lines to be scanned. That is, the number of lines read by the memory control unit 301 from the image memory 102 is increased. However, in the next step S2105, if the value of the scan line number counter lnum is greater than the maximum number of lines (n+1) that the memory control unit 301 can read (Yes in S2105), it is determined that there is a defect in the inspection image 500. In other words, the coordinate position xstart cannot be detected, and an interruption notification "abort" is output from the address determination unit 1209, and the defect inspection apparatus 100 ends the inspection. Also, if the value of the scan line number counter lnum is smaller than the maximum number of lines (n+1) that the memory control unit 301 can read, the process proceeds to S2106.

[0105] In S2106, the memory control unit 301 increases the number of lines to be scanned. In this case, the area detection device 103 increases the number of lines so that the range in which the lines are arranged in the direction along the side of the detection target is wider than before the number of lines was increased. Specifically, the memory control unit 301 reads image data of lines arranged further outward than before the number of lines was increased. In addition, the x-direction counter is reset to "0" by the signal 1208. Thereafter, the process proceeds to S2101, and the above steps are repeated.

[0106] Furthermore, in S1404, if the coordinate position xstart is within the range of xs_base±x_base_d (No in S1404), the coordinate position xstart is within the range of the valid coordinate area, and therefore the coordinate position xstart is determined (S1408). In other words, it is determined that the coordinate position xstart has been detected. In this case, the signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position xstart is stored. The signal 1218 is also supplied to the memory control unit 301, and the memory control unit 301 proceeds to the step of detecting the coordinate position xend in S1101.

[0107] Next, the detection of the coordinate position xend of the right-most side constituting the outer edge of the display area 501, which is performed by the area detection device 103 in S1101 of Fig. 11, will be described. Fig. 22 is a detailed flow diagram showing the processing in S1101. Explanations of steps similar to those in the detection flow of the coordinate position xstart described using Fig. 21 will be omitted where appropriate.

[0108] When the process transitions from S1408 (S1100) to S2200 (S1101), the position at which to start scanning the multiple lines 2001 is set. The setting y_pos sets the y coordinate of D[0], which indicates the center line of the multiple lines 2000 to be scanned, to y_pos. Also, an x-direction counter indicating the position in the x-direction within the memory control unit 301 is set to w-1, and a scan line number counter lnum is set to 5.

[0109] Next, in each step from S2201, scanning is performed from the right end of the inspection image 500 in the −x direction. Specifically, image data P[x,y_pos−2], P[x,y_pos−1], P[x,y_pos], P[x,y_pos+1], and P[x,y_pos+2] for five lines, which is the value of the scan line number counter lnum, are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 1903 to 1907 via D[−2], D[−1], D[0], D[1], and D[2], respectively. The image data P is compared with the threshold values ​​set in each of the comparators 1903 to 1907, and the comparison results are input to the AND circuit 308. At this time, the output (D[-n / 2], D[+n / 2], etc.) from the memory control unit 301 for the lines that are not the target of scanning is greater than the set threshold value, and the output of the connected comparator is "1".

[0110] Next, in S2202, it is determined whether the coordinate position xend has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all comparators 1902 to 1908 are "1" (whether all pixel values ​​are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the x-direction counter is decremented by -1 in S2203, and the process returns to S2201, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the -x direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1504.

[0111] In S1504, the address determination unit 1209 determines whether the coordinate position xend is within the range of the valid coordinate area preset by the settings xe_base and x_base_d. Specifically, it determines whether the coordinate position xend is within the range of xe_base±x_base_d. If the coordinate position xend is greater than xe_base+x_base_d or smaller than xe_base-x_base_d (Yes in S1504), the coordinate position xend is not within the range of the valid coordinate area, and the process proceeds to S2104 and S2105.

[0112] Steps S2104 and S2105 are similar to the flow for detecting the coordinate position xstart described above, and therefore will not be described here. When the flow transitions from S2105 to S2204, in S2204 the memory control unit 301 increases the number of lines to be scanned. Also, the x-direction counter is reset to "w-1" by signal 1208. Thereafter, the flow proceeds to S2201, and the above steps are repeated.

[0113] Furthermore, in S1504, if the coordinate position xend is within the range of xe_base±x_base_d (No in S1504), the coordinate position xend is within the range of the valid coordinate area, and therefore the coordinate position xend is determined (S1506). In other words, it is determined that the coordinate position xend has been detected. In this case, signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position xend is stored. Signal 1218 is also supplied to the memory control unit 301, and the memory control unit 301 proceeds to the step of detecting the coordinate position ystart in S1102.

[0114] Next, the detection of the coordinate position ystart of the top edge that forms the outer edge of the display area 501, which is performed by the area detection device 103 in S1102 of Fig. 11, will be described. Fig. 23 is a detailed flow diagram showing the processing in S1102. Explanations of steps similar to those in the detection flow for the coordinate positions xstart and xend described using Figs. 21 and 22 will be omitted where appropriate.

[0115] When the process transitions from S1506 (S1101) to S2300 (S1102), the position at which to start scanning the multiple lines 2002 is set. The setting x_pos sets the x coordinate of D[0], which indicates the center line of the multiple lines 2002 to be scanned, to x_pos. Also, the y-direction counter, which indicates the position in the y-direction within the memory control unit 301, is set to 0, and the scan line number counter lnum is set to 5.

[0116] Next, in each step from S2301, scanning is performed from the top edge of the inspection image 500 in the +y direction. Specifically, image data P[x_pos-2,y], P[x_pos-1,y], P[x_pos,y], P[x_pos+1,y], and P[x_pos+2,y] for five lines, which is the value of the scan line number counter lnum, are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 1903 to 1907 via D[-2], D[-1], D[0], D[1], and D[2], respectively. The image data P is compared with the threshold values ​​set in each of the comparators 1903 to 1907, and the comparison results are input to the AND circuit 308. At this time, the output (D[-n / 2], D[+n / 2], etc.) from the memory control unit 301 for the lines that are not the target of scanning is greater than the set threshold value, and the output of the connected comparator is "1".

[0117] Next, in S2302, it is determined whether the coordinate position ystart has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all of the comparators 1902 to 1908 are "1" (whether all pixel values ​​are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the y-direction counter is incremented by +1 in S2303, and the process returns to S2301, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the +y direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1604.

[0118] In S1604, the address determination unit 1209 determines whether the coordinate position ystart is within the range of the valid coordinate area preset by the settings ys_base and y_base_d. Specifically, it determines whether the coordinate position ystart is within the range of ys_base±y_base_d. If the coordinate position ystart is greater than ys_base+y_base_d or smaller than ys_base−y_base_d (Yes in S1604), the coordinate position ystart is not within the range of the valid coordinate area, and the process proceeds to S2104 and S2105.

[0119] Steps S2104 and S2105 are similar to the flow for detecting the coordinate positions xstart and xend described above, and therefore will not be described here. When the flow transitions from S2105 to S2304, in S2304 the memory control unit 301 increases the number of lines to be scanned. Also, the y-direction counter is reset to "0" by the signal 1208. Then, the flow proceeds to S2301, and the above steps are repeated.

[0120] Furthermore, in S1604, if the coordinate position ystart is within the range of ys_base±y_base_d (No in S1604), the coordinate position ystart is within the range of the valid coordinate area, and therefore the coordinate position ystart is determined (S1606). In other words, it is determined that the coordinate position ystart has been detected. In this case, a signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position ystart is stored. The signal 1218 is also supplied to the memory control unit 301, and the memory control unit 301 proceeds to the step of detecting the coordinate position yend in S1103.

[0121] Next, the detection of the coordinate position yend of the bottom edge that forms the outer edge of the display area 501, which is performed by the area detection device 103, as shown in S1103 in Fig. 11, will be described. Fig. 24 is a detailed flow diagram showing the processing in S1103. Explanations of steps similar to those in the detection flow for the coordinate positions xstart, xend, and ystart described using Figs. 21 to 23 will be omitted where appropriate.

[0122] When the process transitions from S1606 (S1102) to S2400 (S1103), the position at which to start scanning the multiple lines 2003 is set. The setting x_pos sets the x coordinate of D[0], which indicates the center line of the multiple lines 2003 to be scanned, to x_pos. Also, the y-direction counter, which indicates the position in the y direction within the memory control unit 301, is set to h-1, and the scan line number counter lnum is set to 5.

[0123] Next, in each step from S2401, scanning is performed from the bottom edge of the inspection image 500 in the −y direction. Specifically, image data P[x_pos−2,y], P[x_pos−1,y], P[x_pos,y], P[x_pos+1,y], and P[x_pos+2,y] for five lines, which is the value of the scan line number counter lnum, are read from the image memory 102 via the memory control unit 301. The image data P is input to comparators 1903 to 1907 via D[−2], D[−1], D[0], D[1], and D[2], respectively. The image data P is compared with the threshold values ​​set in each of the comparators 1903 to 1907, and the comparison results are input to the AND circuit 308. At this time, the output (D[-n / 2], D[+n / 2], etc.) from the memory control unit 301 for the lines that are not the target of scanning is greater than the set threshold value, and the output of the connected comparator is "1".

[0124] Next, in S2402, it is determined whether the coordinate position yend has been acquired. Specifically, it is determined whether the AND circuit 308 has output "1" (whether the outputs of all comparators 1902 to 1908 are "1" (whether all pixel values ​​are equal to or greater than the threshold)). If the output of the AND circuit 308 is not "1", the y-direction counter is decremented by -1 in S2303, and the process returns to S2401, where it is determined whether the AND circuit 308 has output "1" for the next pixel in the -y direction. On the other hand, if the output of the AND circuit 308 is "1", the process proceeds to S1704.

[0125] In S1704, the address determination unit 1209 determines whether the coordinate position yend is within the range of the valid coordinate area preset by the settings ye_base and y_base_d. Specifically, it determines whether the coordinate position yend is within the range of ye_base±y_base_d. If the coordinate position yend is greater than ye_base+y_base_d or smaller than ye_base−y_base_d (Yes in S1704), the coordinate position yend is not within the range of the valid coordinate area, and the process proceeds to S2104 and S2105.

[0126] S2104 and S2105 are similar to the flow for detecting the coordinate positions xstart, xend, and ystart described above, and therefore will not be described here. When the flow transitions from S2105 to S2404, in S2404 the memory control unit 301 increases the number of lines to be scanned. Also, the y-direction counter is reset to "h-1" by signal 1208. Thereafter, the flow proceeds to S2401, and the above steps are repeated.

[0127] Furthermore, in S1704, if the coordinate position yend is within the range of ye_base±y_base_d (No in S1704), the coordinate position yend is within the range of the valid coordinate area, and therefore the coordinate position yend is determined (S1706). In other words, it is determined that the coordinate position yend has been detected. In this case, signal 1218 is output from the address determination unit 1209 to the coordinate acquisition unit 309, and the coordinate position ystart is stored. Signal 1218 is also supplied to the memory control unit 301, and the step of detecting each side that constitutes the outer edge of the display area 501 is completed.

[0128] When the coordinate positions xstart, ystart, xend, and yend are detected, in S206, the detected coordinate positions xstart, ystart, xend, and ystart of each side of the display area 501 are output from the area detection device 103 to the defect inspection unit 105. The area detection device 103 may, for example, supply the values ​​of the coordinate positions xstart, xend, ystart, and yend corresponding to each side that constitutes the outer edge of the display area 501 to the defect inspection unit 105. Furthermore, for example, the area detection device 103 may supply the coordinates (xstart, ystart), (xend, ystart), (xstart, yend), and (xend, yend) of the four corners of the display area 501 to the defect inspection unit 105. Next, in S207, the defect inspection unit 105 performs an operation to detect defects in the display area 501 identified by the area detection device 103.

[0129] As described above, when detecting the coordinate positions of each side constituting the outer edge of the display area 501, the area detection device 103 determines whether the coordinate positions are appropriate. If they are not appropriate, the area detection device 103 changes the number of lines to be scanned and scans again. This enables more reliable detection of the display area 501 of the display device 107. Furthermore, increasing the number of lines read from the image memory 102 increases processing time. Therefore, scanning begins with a number of lines (e.g., five lines) that is assumed to be slightly larger than a single defect 400, 800, or 801 caused by the sensor panel of the image acquisition unit 101, and then the number of lines to be scanned is increased by two lines each time scanning is performed again. This minimizes the increase in processing time. Furthermore, similar to the configuration described with reference to FIGS. 10 to 17, it is also possible to detect defective inspection images 500 before inspection by the defect inspection unit 105. As described above, because inspection by the defect inspection unit 105 takes time, a fail-stop, which ends inspection before inspection by the defect inspection unit 105, is possible. This makes it possible to reduce the inspection time for the entire inspection lot, such as when inspecting a plurality of display devices 107. Furthermore, in the present embodiment, an example has been described in which the number of lines to be scanned is increased by two lines when the coordinate position is not appropriate, but the number may be increased by one line, or by three or more lines.

[0130] In each of the above-described embodiments, the four coordinate positions are detected in the order of coordinate position xstart, coordinate position xend, coordinate position ystart, and coordinate position yend, but they may be detected in any order. Furthermore, the threshold values ​​supplied to comparators 302-306 and 1902-1908 may be set to appropriate values ​​based on the light-emitting state of display area 501 of each display device 107, or may be determined based on the light-emitting states of display areas 501 of multiple display devices 107. For example, the threshold value may be set to a value at a level lower than the average value of the luminance values ​​extracted from display areas 501 of multiple display devices 107.

[0131] In this way, the area detection device 103 of this embodiment is less susceptible to defects caused by the sensor panel of the image acquisition unit 101, etc. Therefore, the defect inspection device 100 equipped with the area detection device 103 of this embodiment can extract the display area 501 of the display device 107 with high accuracy and inspect the display area 501 for defects.

[0132] (Other embodiments) The present invention can also be realized by executing the following process: software (programs) that realize the functions of the above-described embodiments are supplied to a system or device via a network or various storage media, and the computer (or CPU, MPU, etc.) of the system or device reads and executes the programs.

[0133] The disclosure of the present specification includes the following area detection apparatus and defect inspection apparatus.

[0134] (Item 1) 1. An area detection device for detecting a display area of ​​a display device from an inspection image captured with the display area illuminated, comprising: The area detection device scanning a plurality of lines set to intersect with sides constituting the outer edge of the display area; An area detection device, comprising: a display area detection unit that detects the coordinate position of each side based on pixel values ​​of pixels of each of the plurality of lines, thereby identifying the display area.

[0135] (Item 2) The area detection device, in scanning the plurality of lines, comparing pixel values ​​of pixels included in the plurality of lines with a threshold value; 2. The area detection device according to item 1, wherein the coordinate position is detected as a position in the scanning direction where all pixel values ​​of the plurality of lines change from less than the threshold to equal to or greater than the threshold.

[0136] (Item 3) 3. The area detection device according to item 2, wherein the area detection device scans the plurality of lines in the inspection image from outside the display area toward the display area.

[0137] (Item 4) The area detection device according to item 2 or 3, characterized in that the area detection device scans the plurality of lines from pixels arranged at the edge of the inspection image toward the display area.

[0138] (Item 5) 5. The area detection device according to any one of items 2 to 4, wherein the threshold value is set according to the pixel value of a pixel located at the center of the inspection image.

[0139] (Item 6) The area detection device according to any one of items 2 to 4, characterized in that the threshold value is set according to the pixel value of a pixel located at the center of a plurality of inspection images including the inspection image.

[0140] (Item 7) The area detection device described in any one of items 2 to 6 is characterized in that, when the detected coordinate position is not within a predetermined range, the area detection device shifts the positions of the multiple lines in a direction along the side and scans the multiple lines again.

[0141] (Item 8) The area detection device if the detected coordinate position is not within a preset range, shifting the positions of the plurality of lines and scanning the plurality of lines are repeated; 8. The area detection device according to item 7, wherein scanning of the plurality of lines is stopped if the coordinate position is not within a preset range after a predetermined number of repetitions.

[0142] (Item 9) The area detection device described in any one of items 2 to 6 is characterized in that, when the detected coordinate position is not within a predetermined range, the area detection device increases the number of lines in the plurality of lines and scans the plurality of lines again.

[0143] (Item 10) The area detection device described in item 9 is characterized in that, when the detected coordinate position is not within a predetermined range, the area detection device increases the number of lines of the multiple lines so that the range in which the multiple lines are arranged in the direction along the side is wider than before the number of lines was increased.

[0144] (Item 11) The area detection device if the detected coordinate position is not within a preset range, increasing the number of lines in the plurality of lines and scanning the plurality of lines are repeated; 11. The area detection device according to item 9 or 10, characterized in that scanning of the plurality of lines is stopped if the coordinate position is not within a preset range until a predetermined number of lines is reached.

[0145] (Item 12) the display area is rectangular; The area detection device according to any one of items 1 to 11, characterized in that the area detection device scans the plurality of lines set for each of the four sides that make up the outer edge.

[0146] (Item 13) the plurality of lines includes a first line and a second line; The area detection device described in any one of items 1 to 12, characterized in that the first line and the second line are composed of pixels arranged adjacent to each other in a direction along the side.

[0147] (Item 14) the plurality of lines include a first line and a second line arranged adjacent to each other; 13. The area detection device according to any one of items 1 to 12, characterized in that, in the direction along the side, pixels that do not constitute the multiple lines are arranged between the first line and the second line.

[0148] (Item 15) 15. The area detection device according to any one of items 1 to 14, wherein the pixel at the center of the inspection image in the direction along the side is arranged in the range in which the plurality of lines are arranged in the direction along the side.

[0149] (Item 16) Item 16. The area detection device according to item 15, wherein the central line among the plurality of lines is configured by the central pixel.

[0150] (Item 17) 15. The area detection device according to any one of items 1 to 14, wherein a central line among the plurality of lines is selected according to pixel values ​​of the display area.

[0151] (Item 18) An area detection device according to any one of items 1 to 17; an image acquisition unit for acquiring the inspection image; a defect inspection unit that inspects the display area identified by the area detection device for defects; A defect inspection device comprising:

[0152] (Item 19) a storage unit that stores the size of a defect appearing in the inspection image according to the characteristics of the image acquisition unit; Item 19. The defect inspection device according to item 18, wherein the range in which the plurality of lines are arranged in the direction along the side is set to be larger than the size of the defect stored in the memory unit.

[0153] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0154] 103: Area detection device, 107: Display device, 500: Inspection image, 501: Display area, 502 to 505, 900 to 903, 1300 to 103, 2000 to 2003: Multiple lines, xstart, xend, ystart, yend: Coordinate positions

Claims

1. 1. An area detection device for detecting a display area of ​​a display device from an inspection image captured with the display area illuminated, comprising: The area detection device scanning a plurality of lines set to intersect with sides constituting the outer edge of the display area; An area detection device, comprising: a display area detection unit that detects the coordinate position of each side based on pixel values ​​of pixels of each of the plurality of lines, thereby identifying the display area.

2. The area detection device, in scanning the plurality of lines, comparing pixel values ​​of pixels included in the plurality of lines with a threshold value; The area detection device according to claim 1 , wherein the coordinate position is detected as a position in the scanning direction where all pixel values ​​of the plurality of lines change from less than the threshold value to equal to or greater than the threshold value.

3. The area detection device according to claim 2 , wherein the area detection device scans the plurality of lines in the inspection image from outside the display area toward the display area.

4. 3. The area detection device according to claim 2, wherein the area detection device scans the plurality of lines from pixels arranged at an edge of the inspection image toward the display area.

5. 3. The area detection device according to claim 2, wherein the threshold value is set in accordance with the pixel value of a pixel located at the center of the inspection image.

6. 3. The area detection device according to claim 2, wherein the threshold value is set in accordance with a pixel value of a pixel located at the center of a plurality of inspection images including the inspection image.

7. The area detection device according to claim 2, characterized in that, when the detected coordinate position is not within a predetermined range, the area detection device shifts the positions of the multiple lines in a direction along the side and scans the multiple lines again.

8. The area detection device if the detected coordinate position is not within a preset range, shifting the positions of the plurality of lines and scanning the plurality of lines are repeated; 8. The area detection device according to claim 7, wherein scanning of the plurality of lines is stopped if the coordinate position is not within a preset range after a predetermined number of repetitions.

9. The area detection device according to claim 2, characterized in that, when the detected coordinate position is not within a predetermined range, the area detection device increases the number of lines in the plurality of lines and scans the plurality of lines again.

10. The area detection device of claim 9, characterized in that, when the detected coordinate position is not within a predetermined range, the area detection device increases the number of lines of the multiple lines so that the range in which the multiple lines are arranged in the direction along the side is wider than before the number of lines was increased.

11. The area detection device if the detected coordinate position is not within a preset range, increasing the number of lines in the plurality of lines and scanning the plurality of lines are repeated; 10. The area detection device according to claim 9, wherein scanning of the plurality of lines is stopped if the coordinate position is not within a preset range until a predetermined number of lines is reached.

12. the display area is rectangular; 2. The area detection device according to claim 1, wherein the area detection device scans the plurality of lines set for each of the four sides that form the outer edge.

13. the plurality of lines includes a first line and a second line; 2. The area detection device according to claim 1, wherein the first line and the second line are made up of pixels arranged adjacent to each other in a direction along the side.

14. the plurality of lines include a first line and a second line arranged adjacent to each other; 2. The area detection device according to claim 1, wherein pixels that do not constitute the plurality of lines are arranged between the first line and the second line in the direction along the side.

15. 2. The area detection device according to claim 1, wherein a pixel at the center of the inspection image in the direction along the side is located within a range in which the plurality of lines are located in the direction along the side.

16. 16. The area detection device according to claim 15, wherein a central line among the plurality of lines is formed by the central pixel.

17. 2. The area detection device according to claim 1, wherein a central line of the plurality of lines is selected in accordance with pixel values ​​of the display area.

18. An area detection device according to any one of claims 1 to 17; an image acquisition unit for acquiring the inspection image; a defect inspection unit that inspects the display area identified by the area detection device for defects; A defect inspection device comprising:

19. a storage unit that stores the size of a defect appearing in the inspection image according to the characteristics of the image acquisition unit; 19. The defect inspection device according to claim 18, wherein the range in which the plurality of lines are arranged in the direction along the side is set to be larger than the size of the defect stored in the memory unit.

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