JP2014002178A - Correction method of alignment layer, correction apparatus of alignment layer and manufacturing method of liquid crystal panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a correction method of an alignment layer capable of accurately detecting a defect in the alignment layer and correcting it.SOLUTION: A correction method of a defect of an alignment layer includes: a step (a) of acquiring an image of a pixel pattern (a repeated pattern) in the surface of the alignment layer formed on the surface of a substrate; a step (b) of acquiring adjacent images (four images positioned vertically and horizontally) around the image of the pixel pattern; a step (c) of synthesizing the image of the pixel pattern and an image connecting the adjacent images; and a step (d) of specifying the defect of the alignment layer by comparing the image of the pixel pattern in the connected images with the adjacent images.

Description

  The present invention relates to an alignment film correction method, an alignment film correction apparatus, and a liquid crystal panel manufacturing method. In particular, the present invention relates to a method and a correction apparatus for automatically correcting an alignment film while accurately detecting defects in the alignment film.

  A liquid crystal panel, which is a component of a liquid crystal display device, has a structure in which a pair of substrates are opposed to each other with a predetermined gap secured. A liquid crystal layer containing liquid crystal molecules is sealed in the gap between the substrates. In addition, an alignment film for regulating the alignment state of the liquid crystal molecules is formed on the surfaces of both substrates in contact with the liquid crystal layer.

  In this alignment film, defects such as adhesion of foreign matter and formation of pinholes may occur. In other words, foreign matters may adhere to the surface of the alignment film due to foreign matters mixed in the alignment film forming step. Further, as the foreign matter is removed, a pinhole may be locally formed in the alignment film, or the alignment film material may be repelled during the film formation to cause a pinhole. When such a defect occurs in the alignment film, the defect may be as small as several tens of microns, but an image may not be normally displayed at the location where the defect has occurred and may be defective. In view of this, a method has been proposed in which an alignment film material is applied again to a defect generated in the alignment film and corrected to improve the quality (for example, Patent Document 1).

International publication WO2011 / 125982 Japanese Patent Application Laid-Open No. 2008-77379

  When a defect of the alignment film has occurred, the defect is repaired using a defect repair device. In the repair operation, first, it is necessary to detect a repair spot (defect spot) by the defect repair apparatus. More specifically, even when the defect position (coordinates) is specified in advance before the substrate on which the alignment film is formed is placed on the defect correcting device, a coordinate shift occurs when the substrate is placed on the defect correcting device. Therefore, it is necessary to specify the exact position of the defect in the correction by the defect correction device. Of course, when the defect position (coordinates) is not specified before being arranged in the defect correction apparatus, it is necessary to detect the defect and its position by the defect correction apparatus.

  As one of the methods for detecting defects generated in the alignment film, it is conceivable to specify the position using a difference method (adjacent comparison method). In this method, an area corresponding to one minimum repetitive pattern is compared with an area corresponding to at least the upper, lower, left and right positions of the minimum repetitive pattern (for example, a pixel area), and a portion having the largest change amount is recognized as a defect.

  More specifically, first, in the original image including the repetitive pattern input by the camera, comparison pixels that are separated from the target pixel by the pattern pitch are set. Then, an image processing process for determining pass / fail is executed based on the luminance values of the target location (for example, target pixel) and the comparison point (for example, comparison pixel). When this process is executed, only normal repetitive patterns are erased, and defects in the patterns are detected. The process from pattern erasing to defect detection performed by this series of image processing is called a difference method (adjacent comparison method). In particular, a method in which four comparison points (comparison pixels) are set on the top, bottom, left, and right sides of a target location (target pixel) may be called a cross comparison method.

  In the difference method (adjacent comparison method), pass / fail judgment is performed between pixels having a relatively short distance, and therefore, it is possible to reduce erroneous detection of errors due to variations in luminance values due to repetitive pattern shifts, illumination unevenness, and the like. In other words, when ideal master image data (comparison pixel data) and a target location (target pixel data) are compared, there is a high possibility that a defect cannot be detected correctly because of the influence of illumination unevenness. In the case of the difference method, such influence can be mitigated.

  However, when the defect detection is performed using the difference method (adjacent comparison method), there is an upper limit (for example, a rectangle of 1.79 μm × 2.37 μm) in the image size that can be acquired by the camera of the existing defect correction apparatus. There is a problem of doing. For this reason, even if an attempt is made to acquire an area corresponding to the minimum number of repetitive patterns necessary for the up / down / left / right comparison, the area does not fall within the range that can be imaged by the camera of the defect correction apparatus. In order to solve this problem, it is necessary to arrange multiple cameras and acquire images of the area corresponding to the minimum number of repeated patterns required for vertical and horizontal comparisons. Therefore, there is a problem that the cost for modifying the existing device for mounting the camera is required.

  In addition, although it is not the difference method disclosed in order to detect the defect of alignment film, the difference method disclosed by patent document 2 is performed using the image detection apparatus which has the structure shown in FIG. More specifically, first, the initial background image data obtained by imaging is given to the difference calculation unit 301. The initial background image data is also given to the background image data update unit 304. Next, the current frame image data at the present time is given to the difference calculation unit 301. The difference calculation unit 301 performs a difference calculation for obtaining a difference between the current frame image data and the current background image data, and outputs the difference calculation result as difference image data. Next, the binarization processing unit 302 performs threshold determination on the difference image data, and outputs binarized image data. The binarized image data is subjected to a labeling process by the labeling processing unit 303, and a label value for the difference image area is output. For each difference image area distinguished by the label value, a predetermined determination is performed on each difference image area.

  Even if the differential method is applied to detect a defect in the alignment film using the image detection apparatus having the configuration shown in FIG. 7, the same problem as described above occurs. In other words, even when the technique disclosed in Patent Document 2 is applied, the problem that the regions corresponding to the minimum number of repeated patterns necessary for the up / down / left / right comparison in the alignment film cannot be fully captured by the camera is not solved. .

  The present invention has been made in view of the above points, and its main purpose is an alignment film capable of accurately detecting and correcting defects in the alignment film without modifying the physical correction device. It is an object of the present invention to provide a correction method, an alignment film correction device, and a liquid crystal panel manufacturing method.

  The correction method according to the present invention is a method for correcting defects in an alignment film formed on the liquid crystal layer side of a pair of substrates in a liquid crystal panel, and an image of a pixel pattern on the surface of the alignment film formed on the surface of the substrate. Step (a) for obtaining the image, Step (b) for obtaining an image adjacent to the image of the pixel pattern, and a step of synthesizing an image obtained by joining the image of the pixel pattern and the image adjacent to each other (C) and a step (d) of identifying a defect in the alignment film by comparing the image of the pixel pattern in the joined image and the adjacent image.

  In a preferred embodiment, the pixel pattern is a repeating pattern in the liquid crystal panel.

  In a preferred embodiment, the repeating pattern is a pixel pattern for two adjacent pixels.

  In a preferred embodiment, in the step (a), using one camera, the image of the pixel pattern and four adjacent images positioned up and down and left and right around the pixel pattern are acquired, and the step In (c), the images acquired using the one camera are synthesized.

  In a preferred embodiment, in the step (b), eight adjacent images located at the top, bottom, left, right, diagonally up and down, and diagonally left and up centered on the pixel pattern image are acquired, and the step (c) ), An image obtained by joining the pixel pattern and the eight adjacent images is synthesized.

  In a preferred embodiment, after the step (d), the step of centering the position of the identified defect and the step of correcting the identified defect after the centering are included.

  In a preferred embodiment, the defect of the alignment film is at least one of a foreign material formed on the alignment film and a hole formed in the alignment film.

  In a preferred embodiment, the substrate on which the alignment film is formed is a mother glass substrate.

  The method for manufacturing a liquid crystal panel according to the present invention includes a step of preparing a substrate corrected using the correction method and a step of bonding the substrates.

  A correction device according to the present invention is a device for correcting defects in an alignment film formed on the liquid crystal layer side of a pair of substrates in a liquid crystal panel, and an image of a pixel pattern on the surface of the alignment film formed on the surface of the substrate. An image acquisition unit that acquires an image adjacent to the image of the pixel pattern as a center, and an image obtained by combining the image of the pixel pattern acquired by the image acquisition unit and the adjacent image A synthesis unit; and a defect identification unit that identifies a defect of the alignment film by comparing the image of the pixel pattern in the joined image and the adjacent image.

  According to the present invention, in a method for correcting a defect in an alignment film, after acquiring a pixel pattern and an adjacent image on the surface of the alignment film, an image obtained by combining these images is synthesized, and then in the image that is connected The defect of the alignment film is specified by comparing the pixel pattern in FIG. Therefore, it is possible to synthesize and create an image of a range in which a single camera can specify a defect without acquiring an image of a range necessary for specifying the defect by comparison using a plurality of cameras. As a result, a wide range of images can be connected and generated by software, so defects in the alignment film can be detected and corrected accurately without physical modification in the correction device. Can do.

It is a flowchart which shows schematic structure of the method of correcting the defect of the alignment film which concerns on one Embodiment of this invention. It is a block diagram which shows schematic structure of the apparatus which corrects the defect of the alignment film which concerns on one Embodiment of this invention. (A) is a figure which shows the maximum size and minimum repeating pattern of the acquisition image on the surface of an alignment film, and (b) is a figure which shows the synthesized image which synthesize | combined several acquisition images. 4 is a flowchart for explaining a method of correcting a defect in an alignment film according to an embodiment of the present invention. (A)-(d) is process sectional drawing for demonstrating the process of correcting the foreign material formed in the surface of alignment film. (A)-(d) is process sectional drawing for demonstrating the process of correcting the pinhole formed in the surface of alignment film. It is a block diagram which shows schematic structure of the image detection apparatus 300 using a difference method.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following drawings, for simplification of description, members and parts having the same action are denoted by the same reference numerals, and redundant description may be omitted or simplified. In addition, the dimensional relationship (length, width, thickness, etc.) in each drawing does not necessarily accurately reflect the actual dimensional relationship. In addition, hatching in the drawing is given mainly for the purpose of easy understanding of the constituent elements, and does not necessarily represent the elements of the material.

  Further, matters necessary for the implementation of the present invention other than matters specifically mentioned in the present specification can be grasped as design matters of those skilled in the art based on the prior art in this field. The present invention can be carried out based on the contents disclosed in the present specification and drawings and the common general technical knowledge in the field. In addition, the present invention is not limited to the following embodiments.

  FIG. 1 is a flowchart showing a schematic configuration of a method for correcting defects in an alignment film according to an embodiment of the present invention. FIG. 2 is a block diagram showing a schematic configuration of a defect correction apparatus 100 used in the method for correcting a defect in an alignment film according to an embodiment of the present invention.

  The liquid crystal panel of this embodiment is composed of a pair of translucent substrates, that is, an array substrate on which a thin film transistor (TFT) is formed, and a color filter substrate (CF substrate) including a color filter layer. ing. In a liquid crystal panel, by applying an electric field between the array substrate and the CF substrate, the alignment state of the liquid crystal molecules in the liquid crystal layer located between the two substrates is changed, and the amount of light transmitted is controlled for each pixel. By doing so, a desired image is displayed.

The array substrate and the CF substrate are respectively composed of separate glass substrates, and an alignment film for regulating the alignment state of liquid crystal molecules is formed on the surface facing the liquid crystal layer, for example. The substrates on which the alignment film is formed are bonded to each other after dropping the liquid crystal material, whereby a liquid crystal panel can be manufactured. In the manufacturing process of the liquid crystal panel, first, the glass substrate on the array side (mother glass) and the glass substrate on the color filter side (mother glass) are processed in separate steps. The mother glass in which the liquid crystal panel portion having a predetermined dimension is multi-faced is, for example, a glass substrate with a side of 1 meter or more. Note that the specific configuration and construction method of the liquid crystal panel, the components and the formation method of the alignment film, and the like are the common technical knowledge of those skilled in the art, and thus detailed description thereof is omitted.

  As shown in FIG. 1, in the alignment film defect correcting method of this embodiment, first, images of a plurality of regions on the surface of the alignment film formed on the substrate are acquired (step S10). In the present embodiment, an image of a pixel pattern (one repetitive pattern) on the surface of the alignment film formed on the surface of the substrate and an adjacent image centering on the image of the pixel pattern are acquired. Specifically, an image (predetermined pixel region) of one repetitive pattern on the surface of the alignment film formed on the surface of the substrate is acquired, and the image is positioned vertically and horizontally around the image of the one repetitive pattern. Acquire four images.

  Next, the images acquired in step S10 are combined (step S11). In the present embodiment, an image obtained by joining an image of a pixel pattern (specific pixel pattern) and an image adjacent to the pixel pattern is synthesized. Specifically, an image of one repetitive pattern and four images, upper, lower, left, and right adjacent thereto are synthesized. As a result, it is possible to create a wide-area image (an image that can be subjected to the difference method or the cross comparison method) including an image to be detected and an image in which four points can be set from the upper, lower, left, and right sides.

  Next, based on the image synthesized in step S11, a defect in the alignment film is specified using a difference method. That is, by comparing the image of the pixel pattern (specific pixel pattern) and the adjacent image in the synthesized and joined image (for example, by comparing with the luminance value), the alignment film defect is identified. To do. Specifically, the difference calculation is performed using the composite image in step S11 (step S12). In the present embodiment, a difference calculation is performed based on the luminance value between the areas constituting the composite image. Next, binarization processing is performed on the difference calculation result data calculated in step S12 (step S13). In this embodiment, binarized data is obtained by performing, for example, threshold determination on the difference calculation result data.

  Thereafter, based on the binarized data obtained in step S13, defect detection and defect position are specified (step S14). In step S14, only the area portion corresponding to the minimum repetitive pattern having no defect is erased, and the area portion corresponding to the minimum repetitive pattern having the defect can be detected.

  FIG. 2 shows a configuration of the alignment film defect correcting apparatus 100 of the present embodiment, and the processes (steps S10 to S14) shown in FIG. 1 can be executed. The defect correction apparatus 100 of the present embodiment includes an image acquisition unit 24, an image synthesis unit 20, a difference calculation unit 21, a binarization processing unit 22, and a defect determination unit 23, and each element (24, 20, 21, 22 and 23) can perform processing corresponding to the above processes (steps S10 to S14).

  More specifically, the image acquisition unit 24 of the defect correction apparatus 100 acquires images of a plurality of regions on the surface of the alignment film formed on the substrate. The image acquisition unit 24 includes a camera (imaging device), and is, for example, a CCD image sensor or a CMOS image sensor. The image acquisition unit 24 according to the present embodiment can acquire images of a plurality of regions on the surface of the alignment film by moving in a predetermined direction on the stage on which the substrate is placed by an operation of a moving mechanism.

  Each element (24, 20, 21, 22, 23) constituting the defect correction apparatus 100 of the present embodiment is formed of a semiconductor integrated circuit, for example, an MPU (micro processing unit) or a CPU (central processing unit). Unit) and a storage device. The storage device is, for example, a semiconductor memory, a hard disk (HDD), an optical disk, a magneto-optical disk, or the like. The defect correction apparatus 100 of the present embodiment is further connected to an input device (keyboard, mouse, touch panel, etc.) and an output device (display, etc.). For these elements, a general-purpose PC (personal computer) can be used. Note that the defect correction method (defect detection method or defect identification method) of the present embodiment can be stored in the storage device of the defect correction apparatus 100 in the form of a defect identification program, and the defect identification program is activated. By doing so, the function of the defect correction apparatus 100 is realizable.

  FIG. 3A shows an acquired image 30 having the maximum size that can be acquired by the image acquisition unit (camera) 24 of the defect correction apparatus 100. Specifically, the upper limit of the acquired image of the maximum size in this example is 2.37 μm × 1.79 μm (rectangle), for example. In the acquired image 30 of the maximum size, an area 31 corresponding to the minimum repetitive pattern is shown. In the illustrated example, a pixel pattern composed of R (red), G (green), and B (blue) sub-pixels (picture elements) is formed on the surface of the substrate. The minimum repeating pattern here is: It consists of a pixel pattern for two pixels. In addition, when it becomes the minimum repeating pattern for 1 pixel, what is necessary is just to make the thing of the unit into one repeating pattern.

  In the present embodiment, the region 31 corresponding to this minimum repeating pattern is acquired by the image acquisition unit 24. In the example shown in FIG. 3A, a defect (defect portion) 32 exists in the region 31 corresponding to the minimum repetitive pattern. FIG. 3B shows a composite image in which a plurality of repetitive patterns (minimum repetitive patterns) are arranged. In the example shown in FIG. 3B, first, the image acquisition unit (camera) 24 corresponds to the region 31 corresponding to the minimum repeat pattern located at the center and the minimum repeat pattern located above, below, left and right. An image of the region 31a and the region 31b corresponding to the minimum repeating pattern located on the left diagonal and right diagonal is acquired. Thereafter, the image synthesis unit 20 synthesizes the images of these areas 31, 31a, and 31b to generate the entire synthesized image shown in FIG. It should be noted that in executing the difference method, it is sufficient to combine the images of the regions 31 and 31a. However, the accuracy can be improved by further combining the image of the region 31b.

  It should be noted that the pixel data of the region 31 corresponding to a predetermined pixel pattern (one repetitive pattern) is not compared with the ideal master image data (comparison pixel data), but is compared with adjacent pixel data (such as 31a). This is because the comparison by the difference method is more accurately performed. That is, when compared with image data (or ideal master image data) of a non-adjacent location and attention image data (31), a difference in reflected light, a difference in color, or an illumination condition due to bending of the substrate It is difficult to obtain the correct comparison result due to the influence of the difference. Such a situation can be suppressed when comparing the target image data (31) and the adjacent image data (31a, etc.). Note that at least three pieces of image data (attention image data and two pieces of image data to be compared) are necessary for comparison using the difference method. However, the comparison is not limited to the minimum number, and the cross comparison method is used. May be processed so as to obtain upper, lower, left and right images. Also, the reason for connecting adjacent image data into one large image data is to make it easier to detect defects at the joints.

  Next, based on the composite image shown in FIG. 3B, the difference calculation unit 21 performs a difference calculation. Here, the difference calculation unit 21 is used to perform a difference calculation based on the luminance value between the regions (31, 31a, etc.) constituting the composite image. Next, the binarization processing unit 22 performs threshold determination on the difference calculation result data obtained by the difference calculation unit 21 to obtain binarized data. Finally, when an image processing process for defect detection is performed using the defect determination unit 23 based on the binarized data, only the area portion corresponding to the minimum repetitive pattern in which no defect exists is erased, and the defect 32 is deleted. It can be detected and its position can be specified. In the present embodiment, in the composite image shown in FIG. 3B, the region portions 31a and 31b corresponding to the minimum repetitive pattern are erased, and a defect exists in the region 31 corresponding to the minimum repetitive pattern located in the center portion. It can be converted into shape data. Thereby, since the defect 32 can be detected and the position of the defect 32 can be specified, the defect correction apparatus 100 according to this embodiment can automatically execute the defect correction.

  According to the embodiment of the present invention, in the method of correcting the defect 32 of the alignment film, one repetitive pattern 31 on the surface of the alignment film 31 and four images 31a positioned on the top, bottom, left and right (and four images positioned diagonally). After obtaining 31b), the images can be combined, and the alignment film defects 32 can be identified using the difference method based on the combined images. Therefore, it is possible to obtain an image in a range in which the difference method can be applied with one camera without acquiring images (31, 31a) in a range in which the difference method can be applied using a plurality of cameras. As a result, it is possible to acquire a wide range of images in terms of software, so that the defects 32 in the alignment film can be accurately detected and corrected without physical modification in the correction device.

  On the other hand, according to the conventional technique, as shown in FIG. 3A, when only an image including only a region composed of one of the minimum repetitive patterns 31 can be obtained, the minimum number necessary for the difference method is obtained. There has been a problem that an area (31, 31a, etc.) corresponding to a repetitive pattern cannot be acquired. According to the present embodiment, as described above, the defect detection of the alignment film is performed using the difference method in order to acquire the image of the region corresponding to the minimum number of repetitive patterns necessary for the difference method and generate the composite image. It can be performed.

  To further explain, when simply acquiring images (31, 31a) in a range where the difference method can be applied, in addition to expanding the image acquisition region using a plurality of cameras, use a camera with a high resolution and a large image acquisition range. Is also possible. However, since the minimum repeating pattern differs for each substrate constituting the liquid crystal panel, even if the difference method can be executed on a certain substrate, the difference method can be executed on the other substrate even in the widened image acquisition range. Then it may be insufficient. Of course, a camera with a wider image acquisition range may be used. However, a camera with a specification higher than necessary increases the equipment cost, which is not preferable. In the configuration of the present embodiment, since a composite image having an appropriate image acquisition range can be created in terms of software, there are advantages that the cost is low and the applicability is wide.

  Next, the method of the present embodiment including the alignment film correction process will be described with reference to FIGS. FIG. 4 is a flowchart showing an example of the overall configuration of the correction method of the present embodiment.

  As shown in FIG. 4, first, in step S40, the substrate is cleaned before the alignment film is applied. The substrate is a mother glass substrate as described above, but may be a substrate corresponding to one liquid crystal panel. Next, in step S41, an alignment film is applied to the substrate. The alignment film is made of, for example, a polyimide (PI) film. In the present embodiment, the alignment film is applied by an inkjet method, but the alignment film may be applied by other methods.

  Next, in step S42, after the alignment film made of the PI film applied to the substrate is temporarily dried, in step S43, the PI alignment film is inspected using an inspection machine. That is, in step S44, it is determined whether or not the alignment film needs to be corrected based on the inspection result. If “YES” in step S44, that is, if it is determined that the alignment film needs to be corrected, the process proceeds to step S45 to perform a correction process. The correction step (defect detection step, defect identification step) here is based on the steps S10 to S14 shown in FIG. If “NO” in step S44, that is, if it is determined that the alignment film need not be corrected, the process proceeds to step S50.

  Next, after the defect is specified in step S45, centering is performed in step S46 so that the defect is positioned in the center based on the defect position of the alignment film. That is, processing (centering) is performed so that the coordinates of the defect are located at the center so that the correcting means shown in FIGS. 5 and 6 can repair the defect. Next, in step S47, it is determined whether or not a foreign substance exists in the centered defect (or an area corresponding to the minimum repetitive pattern including the defect). And when it determines with a foreign material existing, it progresses to step S48. On the other hand, if it is determined that no foreign matter exists, the process proceeds to step S49.

  In step S48, the foreign matter polishing step shown in FIGS. 5A to 5D is performed. In this example, as shown in FIG. 5A, the foreign matter 32a is locally attached to the alignment film 51 formed on the insulating film 50 on the substrate. In this case, as shown in FIG. 5B, the polishing tape 53 is moved in the direction of the arrow while the polishing head 52 is loaded downward. Next, when the polishing head 52 and the polishing tape 53 are raised, as shown in FIG. 5C, the foreign matter 32b whose upper part is flattened is formed. When the polishing of the foreign matter is completed, as shown in FIG. 5D, the upper portion becomes the foreign matter 32b flattened, and the defective portion can be determined as a non-defective product.

  Next, in step S49, a process of correcting pinholes in the PI film shown in FIGS. 6A to 6D is performed. In this example, as shown in FIG. 6A, the pinhole 32c is locally located in the alignment film 61 formed on the insulating film 60 on the substrate. In this case, as shown in FIG. 6B, a correction stamp 63 provided at the tip of the jig 62 is provided on the insulating film 60 and the alignment film 61 so as to cover the region where the pinhole 32c is formed. Then, the correction ink 64 is applied. Next, when the applied correction ink 64 is dried, the solid content 65 of the PI film as shown in FIG. 6C can remain. Thereafter, as shown in FIG. 6D, the defect due to the pinhole 32c can be eliminated by the corrected PI film 66 covering the pinhole 32c. As a result, the defective portion can be determined as a non-defective product.

  Thereafter, in step S50, the alignment film made of the PI film is baked. After completing the formation of the alignment film as described above, the process proceeds to a known substrate bonding step, and then the liquid crystal panel is completed.

As mentioned above, although this invention was demonstrated by suitable embodiment, such description is not a limitation matter and of course various modifications are possible. For example, in the above-described embodiment, a substrate for a liquid crystal panel, particularly a mother glass substrate, has been described as the substrate, but is not limited thereto. As described above, the method of this embodiment can be applied not only to mother glass but also to defect inspection / defect identification of a repetitive pattern on a single liquid crystal panel substrate. Furthermore, the present invention is not limited to the liquid crystal panel, and can be applied to inspection of a repeated pattern (a technique using a difference method) of a substrate constituting a display device such as a plasma display or an organic EL display.
In the above-described embodiment, the pixel patterns of the three primary colors of red (R), green (G), and blue (B) have been described. However, the present embodiment is not limited to this, and the method of the present embodiment is not limited to red (R), green The present invention can also be applied to a pixel pattern of four primary colors of (G), blue (B), and yellow (Y). In addition, the alignment film includes not only a film whose alignment is controlled using a rubbing method but also a film whose alignment is controlled by a photo-alignment method. In that case, a photo-alignment material (for example, a photo-alignment polyimide) Material).

  Further, since the point is that the images of the camera are combined to form a wide range of images to which the difference method can be applied, it is not limited to a specific method of a specific difference method. Further, the foreign material polishing method and the pinhole repair method are not limited to specific methods. In addition, the point is to combine the images captured by one camera, but the area of the large-sized substrate (mother glass) is divided (for example, divided into two parts, such as the right side and the left side), and a plurality of cameras ( The present invention can also be applied to the case where the image acquisition process is performed simultaneously by two cameras). In other words, the plurality of cameras (two cameras) here are only those in which one camera described in the embodiment of the present invention operates at different locations.

  ADVANTAGE OF THE INVENTION According to this invention, the correction method of the alignment film which can detect and correct the defect in an alignment film accurately can be provided.

DESCRIPTION OF SYMBOLS 20 Image composition part 22 Binarization processing part 23 Defect determination part 24 Image acquisition part 30 Camera acquisition image 31 Area | region 32 corresponding to the minimum repeating pattern Defect 32a, 32b Foreign material 32c Pinhole 50 Insulating film 51 Orientation film 52 Polishing head 53 Polishing tape 60 Insulating film 61 Alignment film 62 Jig 63 Correction stamp 64 Correction ink 65 Solid content 66 Correction PI film 100 Defect correction apparatus 300 Image detection apparatus

Claims (10)

A method for correcting defects in an alignment film formed on a liquid crystal layer side of a pair of substrates in a liquid crystal panel,
A step (a) of obtaining an image of a pixel pattern on the surface of the alignment film formed on the surface of the substrate;
A step (b) of obtaining an adjacent image centering on the image of the pixel pattern;
Synthesizing an image obtained by joining the image of the pixel pattern and the adjacent image;
And a step (d) of identifying a defect of the alignment film by comparing an image of the pixel pattern in the joined image and the adjacent image.   The correction method according to claim 1, wherein the pixel pattern is a repetitive pattern in the liquid crystal panel.   The correction method according to claim 2, wherein the repetitive pattern is a pixel pattern for two adjacent pixels. In the step (a), using one camera, an image of the pixel pattern and four adjacent images positioned up and down and left and right around the pixel pattern are acquired,
The correction method according to any one of claims 1 to 3, wherein, in the step (c), the images acquired using the one camera are synthesized. In the step (b), eight adjacent images located at the top, bottom, left, right, diagonally up and down, and diagonally left and up centered on the image of the pixel pattern are acquired,
The correction method according to any one of claims 1 to 3, wherein in the step (c), an image obtained by joining the pixel pattern and the eight adjacent images is synthesized. After the step (d), centering the position of the identified defect;
The correction method according to claim 1, further comprising: correcting the identified defect after the centering.   7. The correction method according to claim 1, wherein the defect in the alignment film is at least one of a foreign matter formed on the alignment film and a hole formed in the alignment film.   The correction method according to claim 1, wherein the substrate on which the alignment film is formed is a mother glass substrate. Preparing a substrate that has been corrected using the correction method according to claim 1;
And a step of bonding the substrates together. An apparatus for correcting defects in an alignment film formed on the liquid crystal layer side of a pair of substrates in a liquid crystal panel,
An image acquisition unit that acquires an image of a pixel pattern on the surface of the alignment film formed on the surface of the substrate, and an image adjacent to the image of the pixel pattern;
An image synthesis unit that synthesizes an image obtained by joining the image of the pixel pattern acquired by the image acquisition unit and the adjacent image;
A correction device, comprising: a defect specifying unit that specifies a defect of the alignment film by comparing an image of the pixel pattern in the joined image and the adjacent image.

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