WO2013031866A1

WO2013031866A1 - Device and method for inspecting display device

Info

Publication number: WO2013031866A1
Application number: PCT/JP2012/071910
Authority: WO
Inventors: 佐々木　崇
Original assignee: シャープ株式会社
Priority date: 2011-08-31
Filing date: 2012-08-29
Publication date: 2013-03-07

Abstract

In an image for inspection displayed on a display screen, if a reference region includes a region having a luminance different from a target luminance, then the gradation of image data corresponding to said region is corrected. On the other hand, if the reference region does not include said region, then the gradation of the image data corresponding to said region is not corrected. By reducing specific display unevenness in this way, a device and a method for inspecting a display device with which degradation in display quality can be prevented are provided.

Description

Display device inspection device and inspection method

The present invention relates to an inspection apparatus and an inspection method for a display device.

Generally, various display irregularities occur on the display screen of a display device (display panel) in terms of design (structure) and manufacturing. For example, in the display screen of the display panel, display unevenness occurs due to an increase in luminance in a region corresponding to a portion where a backlight light source (for example, a fluorescent tube) is arranged. In particular, in a large display panel, pins used during transportation in the manufacturing process and traces of suction appear as display unevenness on the display screen.

(A) of FIG. 23 is a figure which shows a display state when the said display nonuniformity exists in the display screen of a display panel. The display unevenness shown in the horizontal direction is the display unevenness (backlight unevenness) caused by the light source of the backlight arranged on the back side of the display panel, and is shown in other circular or elliptical shapes. Display unevenness is display unevenness (pin unevenness, suction unevenness) caused by the pin mark and the suction mark.

Conventionally, as a technique for reducing the display unevenness, a display device that performs gradation correction of image data for a portion where display unevenness occurs has been proposed (for example, Patent Document 1). Specifically, in the display device of Patent Document 1, the size and position of a rectangular area on the display screen are specified, the gradation is corrected in the range, and the gradation change in the peripheral portion is changed in the vertical and horizontal directions. Display unevenness is reduced by gradually reducing the display unevenness.

23. According to the above configuration, as shown in FIG. 23B, various display unevenness shown in FIG. 23A can be reduced.

Japanese Patent Publication “JP 2005-134560 A (published May 26, 2005)”

However, in the conventional technique, since gradation correction is performed so as to uniformly reduce display unevenness without distinguishing the source of display unevenness, the following problems occur. That is, for example, in the manufacturing process of the display panel, when the pin unevenness and the backlight unevenness are detected, and gradation correction is performed to reduce these display unevenness, a normal display panel in which all display unevenness is reduced ( Display device). However, after that, when the backlight is replaced, and the new backlight does not match the symptoms of the original backlight, the correction to reduce the backlight unevenness in the manufacturing stage corresponds to the new backlight. Therefore, unnecessary correction is applied to the display area corresponding to the correction location, and the display quality may be deteriorated.

In view of the above problems, it is an object of the present invention to provide an inspection device and an inspection method for a display device that can prevent deterioration in display quality by reducing specific display unevenness.

In order to solve the above problems, an inspection apparatus for a display device according to the present invention is provided.
In a display device comprising a display panel and a backlight that emits light to the display panel, the display device is an inspection device that turns on the backlight and inspects the display state of the display panel,
In the inspection image displayed on the display screen, it is determined whether or not an area represented by a brightness different from the target brightness is included in a preset reference area,
When it is determined that the region is included in the reference region, the gradation of the image data corresponding to the region is corrected. On the other hand, when it is determined that the region is not included in the reference region, the region is corrected. The gradation of the image data corresponding to is not corrected.

According to the above configuration, for example, by making the reference area into the circular shape shown in FIG. 5, correction is performed to reduce only unevenness (panel unevenness such as pin unevenness) that matches the reference area, and does not match the reference area. It is possible to adopt a configuration in which correction is not performed for unevenness (backlight unevenness). As described above, since it is possible to correct a specific unevenness, it is possible to prevent a deterioration in display quality that may occur conventionally.

In order to solve the above problems, an inspection apparatus for a display device according to the present invention is provided.
In a display device comprising a display panel and a backlight that emits light to the display panel, the display device is an inspection device that turns on the backlight and inspects the display state of the display panel,
A data input unit for inputting inspection image data on the display screen;
An imaging unit that captures a display image displayed on a display screen based on an input gradation of the inspection image data input by the data input unit;
A detection unit that detects an area represented by a luminance different from the luminance corresponding to the input gradation in the captured image captured by the imaging unit;
A determination unit that determines whether or not the region detected by the detection unit is included in a preset reference region;
When the determination unit determines that the region is included in the reference region, the input gradation corresponding to the region is corrected, while when the region is determined not to be included in the reference region And a correction unit that does not correct the input gradation corresponding to the region.

In order to solve the above problems, a display device inspection method according to the present invention is provided.
In a display device comprising a display panel and a backlight that irradiates light to the display panel, the display device is inspected to display the display panel by turning on the backlight.
In the inspection image displayed on the display screen, it is determined whether or not an area represented by a brightness different from the target brightness is included in a preset reference area,
When it is determined that the region is included in the reference region, the gradation of the image data corresponding to the region is corrected. On the other hand, when it is determined that the region is not included in the reference region, the region is corrected. The gradation of the image data corresponding to is not corrected.

In order to solve the above problems, a display device inspection method according to the present invention is provided.
In a display device comprising a display panel and a backlight that irradiates light to the display panel, the display device is inspected to display the display panel by turning on the backlight.
A data input process for inputting inspection image data on the display screen;
An imaging step of capturing a display image displayed on the display screen based on the input gradation of the inspection image data input in the data input step;
A detection step of detecting an area represented by a luminance different from the luminance corresponding to the input gradation in the captured image captured in the imaging step;
A determination step of determining whether or not the region detected in the detection step is included in a preset reference region;
In the determination step, when it is determined that the region is included in the reference region, the input gradation corresponding to the region is corrected, while when it is determined that the region is not included in the reference region And a correction step in which the input gradation corresponding to the region is not corrected.

As described above, when it is determined that the region is included in the reference region, the inspection device and the inspection method for the display device according to the present invention correct the gradation of the image data corresponding to the region, When it is determined that the region is not included in the reference region, the gradation of the image data corresponding to the region is not corrected. Accordingly, it is possible to provide a display device inspection apparatus and inspection method capable of preventing a decrease in display quality by reducing specific display unevenness.

It is a block diagram which shows schematic structure of the test | inspection apparatus of the liquid crystal display device which concerns on this Embodiment. It is a flowchart which shows operation | movement of the test | inspection apparatus shown in FIG. FIG. 6 is a diagram illustrating a state of an image displayed on a display screen when image data of a predetermined gradation (31 gradations) is input to the liquid crystal display device before performing the inspection process (correction process) according to the first embodiment. . It is a figure which shows the reference | standard area | region set in the inspection apparatus which concerns on Example 1. FIG. It is a figure for demonstrating the determination process in the determination process of the inspection apparatus which concerns on Example 1. FIG. It is a figure which shows the mode of the image displayed on the display screen after the correction process of the inspection apparatus which concerns on Example 1. FIG. It is a figure which shows the mode of the image displayed on the display screen after the correction process of the inspection apparatus which concerns on Example 1. FIG. It is a figure which shows the mode of the image displayed on the display screen after the correction process of the inspection apparatus which concerns on Example 1. FIG. It is a flowchart which shows operation | movement of the test | inspection apparatus which concerns on the modification 1. FIG. 10 is a diagram illustrating a state of an image displayed on a display screen when image data of a predetermined gradation (31 gradations) is input to a liquid crystal display device before performing an inspection process (correction process) according to Example 2. . It is a figure which shows the reference | standard area | region set in the inspection apparatus which concerns on Example 2. FIG. It is a figure for demonstrating the determination process in the determination process of the inspection apparatus which concerns on Example 2. FIG. It is a figure which shows the mode of the image displayed on the display screen after the correction process of the inspection apparatus which concerns on Example 2. FIG. FIG. 10 is a diagram illustrating a state of an image displayed on a display screen when image data of a predetermined gradation (31 gradations) is input to a liquid crystal display device before performing an inspection process (correction process) according to Example 3. . It is a figure which shows the reference | standard area | region set in the inspection apparatus which concerns on Example 3. FIG. It is a figure which shows the mode of the image displayed on the display screen after the correction process of the inspection apparatus which concerns on Example 3. FIG. FIG. 10 is a diagram illustrating a state of an image displayed on a display screen when image data of a predetermined gradation (31 gradations) is input to a liquid crystal display device before performing an inspection process (correction process) according to Example 4. . It is a figure which shows the reference | standard area | region set in the inspection apparatus which concerns on Example 4. FIG. It is a figure for demonstrating the determination process in the determination process of the inspection apparatus which concerns on Example 4. FIG. It is a figure which shows the mode of the image displayed on the display screen after the correction process of the inspection apparatus which concerns on Example 4. FIG. It is a block diagram which shows schematic structure of the liquid crystal display device which concerns on this Embodiment. FIG. 22 is a block diagram illustrating the liquid crystal display device after replacement of the control board in the liquid crystal display device of FIG. 21. (A) is a figure which shows the display state when display nonuniformity exists in the display screen of a display panel, (b) shows the mode of the image displayed on the display screen after the conventional gradation correction | amendment. FIG.

Embodiments of the present invention will be described below with reference to the drawings. In the following, a liquid crystal display device (liquid crystal display) will be described as an example of a display device as an inspection target in the inspection device of the present invention, but the display device as an inspection target is not limited to this, An organic EL display, a plasma display, etc. may be sufficient. The inspection apparatus of the present invention may be included in a display device manufacturing apparatus. In this case, the inspection method of the present invention can also be incorporated into a display device manufacturing method.

FIG. 1 is a block diagram showing a schematic configuration of an inspection apparatus for a liquid crystal display device according to the present embodiment. The inspection device 1 has a function of turning on a backlight (not shown), inspecting the display state of the liquid crystal panel 20 constituting the liquid crystal display device 10, and performing correction processing according to the inspection result. As shown in FIG. 1, the inspection apparatus 1 includes a data input unit 2, an imaging unit 3, a nonuniformity detection unit 4, a determination unit 5, a memory unit 6, and a correction unit 7.

The data input unit 2 inputs predetermined gradation image data (inspection image data) to the liquid crystal display device 10. As a result, the liquid crystal display device 10 lights the backlight and displays an inspection image on the display screen of the liquid crystal panel 20. The predetermined gradation is not particularly limited, but is preferably set to a low gradation so that display unevenness is conspicuous. Further, the predetermined gradation is not limited to one type, and may be set to a plurality of gradation levels.

The imaging unit 3 is configured by, for example, a CCD camera, and images a display image displayed on the display screen based on the input gradation of the inspection image data input by the data input unit 2.

The unevenness detection unit 4 detects unevenness in an area represented by a luminance different from the luminance corresponding to the input gradation in the captured image captured by the imaging unit 3.

The determination unit 5 compares the unevenness (detection unevenness) detected by the unevenness detection unit 4 with the reference area stored in the memory unit 6 and determines whether or not the detected unevenness is included in the reference area. The reference area is stored in the memory unit 6 in advance. A specific reference area will be described later.

The correction unit 7 performs processing according to the determination result of the determination unit 5. Specifically, when it is determined that the detection unevenness is included in the reference area, the input gradation corresponding to the detection unevenness display area is corrected, while the detection unevenness is not included in the reference area. Is determined, the input gradation corresponding to the detection unevenness display area is not corrected.

Next, the reference area stored in the memory unit 6 will be described.

The reference area is set corresponding to the shape of display unevenness appearing on the display screen. Here, although there are various factors in the display unevenness, broadly speaking, as shown in FIG. 23A, the backlight is caused by the light source of the backlight disposed on the back side of the liquid crystal panel 20. Display unevenness on the side (backlight unevenness), and display unevenness on the liquid crystal panel side (panel unevenness) such as pins used during transportation in the manufacturing process of the liquid crystal display device 10 and traces of adsorption. In view of this, it is conceivable that the reference region has vertical or horizontal streaks corresponding to backlight unevenness, and a rectangular, circular or elliptical shape corresponding to panel unevenness. However, in the inspection apparatus 1 according to the present embodiment, the reference region is set to a rectangular shape, a circular shape, or an elliptical shape corresponding to the panel unevenness in order to correct only the panel unevenness without correcting the backlight unevenness. Is done. The reference area is not limited to one type, and a plurality of types of shapes assumed as panel unevenness may be set. Further, the reference area has a size that can be seen by human eyes, and does not include a shape that is small enough not to affect the display quality.

The present inspection apparatus 1 is provided with the above-described configuration to reduce only display unevenness (panel unevenness) caused by the liquid crystal panel 20.

Hereinafter, a specific configuration of the inspection apparatus 1 will be described with specific examples.

(Example 1)
FIG. 2 is a flowchart showing the operation (inspection process) of the inspection apparatus 1.

As a pre-stage of the inspection process by the inspection apparatus 1, the liquid crystal display device 10 to be inspected is manufactured by a known method. Then, the manufactured liquid crystal display device 10 is transported to the inspection area of the inspection device 1.

In the inspection process in the inspection apparatus 1, first, image data (inspection image data) of a predetermined gradation is input to the liquid crystal display device 10 as an inspection image (S1: data input process). Here, it is assumed that solid image data with 31 low gradations (up to 255 gradations) is input. As a result, the liquid crystal display device 10 lights the backlight and displays an inspection image on the display screen of the liquid crystal panel 20.

Next, the display image displayed on the display screen of the liquid crystal panel 20 is imaged by the CCD camera (imaging unit 3) (S2: imaging process). Here, it is assumed that the image shown in FIG. 3 is displayed on the display screen and taken by the CCD camera. In FIG. 3, reference signs A, B, and C are unevenness (panel unevenness) due to pins and suction marks used when the liquid crystal panel 20 is transported, and reference numeral D is a portion where a backlight light source (for example, a fluorescent tube) is arranged. Indicates unevenness (backlight unevenness).

Next, in the captured image (FIG. 3), the unevenness of the area represented by the luminance different from the luminance corresponding to the 31 gradation is detected (S3: detection step). Here, the irregularities A to D in FIG. 3 are detected. If no unevenness is detected on the display screen, the entire display screen area is detected.

Next, the irregularities A to D detected in the detection step are compared with the reference area stored in the memory unit 6 to determine whether the detected irregularity is included in the reference area (S4: determination step). Specifically, for example, it is determined whether or not the detection unevenness is included in the reference region by superimposing the detection unevenness and the reference region by image processing. Here, it is assumed that the reference region is set to the circular shape shown in FIG. In this case, as shown in FIG. 5, it is determined that the irregularities A to C are included in the reference area, and the unevenness D is not included in the reference area.

Here, in the determination step (S4), determination processing is performed for all detection irregularities, and when it is determined that one of them is included in the reference region (YES in S4), the process proceeds to the correction step (S5). On the other hand, when it is determined that all the detection unevenness is not included in the reference region (NO in S4), this inspection process is ended. Here, it is determined that the unevenness D is not included in the reference area, but since it is determined that the unevenness A to C are included in the reference area, the process proceeds to the correction step (S5).

Next, correction processing is performed on the unevenness A to C determined to be included in the reference region in the determination step (S4) (S5: correction step). Specifically, correction is made to the correction gradation stored in advance in the memory unit 6 based on the input gradation (31 gradations here) and the display gradation corresponding to the display luminance. That is, the memory unit 6 stores an LUT in which an input gradation, a display gradation, and a correction gradation are associated with each other. The correction unit 7 refers to the LUT and changes the input gradation to a correction gradation. To do. After the correction process is performed in the correction process, the inspection process of the inspection apparatus 1 ends.

According to the above correction process of the inspection process, the appearance of panel unevenness can be suppressed as shown in FIG.

In the inspection process according to the inspection apparatus 1, since the backlight unevenness is not corrected, the display unevenness (unevenness D: backlight unevenness) is visually recognized as shown in FIG. In this case, even if the backlight is replaced after the liquid crystal display device 10 is shipped as a finished product, the display quality in the manufacturing stage is not further deteriorated. Further, by replacing a normal backlight after shipment, it is possible to eliminate backlight unevenness that has occurred in the manufacturing stage.

In addition, since it is considered that the backlight unevenness is caused by the abnormality of the backlight, the backlight unevenness may be eliminated by replacing the backlight with a normal backlight in the manufacturing stage. For example, in the correction process (S5) of the inspection apparatus 1, by performing an operation of notifying the outside of the backlight (such as a worker) of the abnormality of the backlight, an operation of replacing the backlight unit or the light source with a normal one is performed. it can. According to this configuration, backlight unevenness can be eliminated as shown in FIG. 7 regardless of gradation correction.

Here, in the liquid crystal display device in which the gradation is uniformly corrected for the panel unevenness and the backlight unevenness as in the conventional case, when the backlight is replaced after that, the new backlight does not match the original backlight. In this case, since the gradation correction for reducing the backlight unevenness performed in the manufacturing stage does not correspond to the new backlight, unnecessary correction is applied to the display area corresponding to the correction portion, and the display quality is deteriorated. . In particular, backlight unevenness often has a viewing angle specification and temperature dependency. Therefore, if the backlight unevenness on the display screen is corrected by gradation correction, the display screen may be viewed obliquely or due to differences in temperature environment. There is a risk that the display quality will deteriorate.

On the other hand, in the liquid crystal display device 10 that has been subjected to the correction process in the inspection apparatus 1, gradation correction for backlight unevenness is not performed. Even when the light is replaced, display unevenness due to a new backlight does not appear. Therefore, the display quality does not deteriorate.

In the correction step (S5) in the inspection step according to the present inspection apparatus 1, the LUT (correction data) in which the input gradation, the correction gradation, and the correction area (the locations of unevenness A, B, and C) are associated is displayed on the liquid crystal. The process which stores in the memory 50 (refer FIG. 21) of the display apparatus 10 is performed. Thereby, in the liquid crystal display device 10, since the corrected image is displayed with respect to the predetermined input image data, it is possible to suppress the appearance of display unevenness due to panel unevenness.

Here, in the correction step (S5), more specifically, for example, when the input gradation is the X gradation, the uneven luminance is lower (darker) than the (expected) luminance corresponding to the X gradation. ), The gradation of the uneven portion is corrected to a value larger than the X gradation. In addition, when the luminance of unevenness is higher (brighter) than the luminance corresponding to (expected) the X gradation, the gradation of the uneven portion is corrected to a value smaller than the X gradation. FIG. 8 shows a display state of a display image after correction by gradation correction in a liquid crystal panel having a maximum of 255 gradations. In the drawing, backlight unevenness is omitted for convenience.

(Modification 1)
The inspection process shown in FIG. 2 may be the process shown in FIG. That is, after the correction step (S5) is completed, the process returns to the processing of S1 (data input step) based on the corrected gradation.

Then, the unevenness D is detected in the detection step (S3) through the imaging step (S2), but in the determination step (S4), it is determined that the unevenness D is not included in the reference region. That is, since it is determined that all the detection unevenness is not included in the reference region (NO in S4), this inspection process ends. According to this modification, the process is repeated until the panel unevenness is eliminated, so that the panel unevenness can be reliably reduced.

(Modification 2)
The determination process (S4) of the inspection process shown in FIG. 2 may be the following process. That is, in the determination process in the inspection process according to the modified example 2, the detected unevenness that does not affect the display quality is not subjected to the process of whether or not it is included in the reference region. . Specifically, in the determination step, it is determined whether or not the difference between the luminance corresponding to the input gradation and the luminance of the unevenness exceeds a predetermined value. It is set as the structure which performs the process of whether it is contained. For example, when the input gradation is 31 gradations and the difference between the input gradation and the gradation corresponding to the brightness of the unevenness B in FIG. 3 is smaller than a predetermined value (for example, 0.5 gradation) Since there is a risk that the display quality may be lower than before the correction (brightness difference is widened) due to the gradation correction, correction processing is not performed for such unevenness B.

According to this modification, correction processing can be omitted for display unevenness that does not affect the display quality, so that the power consumption and efficiency of the inspection apparatus 1 can be reduced.

The configurations of the first and second modifications can be applied to the following embodiments.

(Example 2)
Next, when image data of a predetermined gradation (31 gradations) is input to the liquid crystal display device before the inspection process (correction process) in the inspection apparatus 1 is performed, the image shown in FIG. 10 is displayed on the display screen. The operation of the inspection apparatus 1 will be described.

In the following, for convenience of explanation, members having the same functions as those shown in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. In addition, the terms defined in Example 1 are used in accordance with the definitions in the following unless otherwise specified.

In the detection step (S3) after the data input step (S1) and the imaging step (S2) shown in FIG. 2, in the detection image (FIG. 10), the luminance different from the luminance corresponding to 31 gradations. The unevenness of the area represented by is detected. Here, the irregularities a, b, and c in FIG. 10 are detected.

Next, the unevenness a, b, c detected in the detection step (S3) is compared with the reference area stored in the memory unit 6 to determine whether the detected unevenness is included in the reference area (S4). : Judgment process). Here, among the unevenness shown in FIG. 10, unevenness c is backlight unevenness, and unevenness a and b are line unevenness (panel unevenness) caused by scanning signal lines and data signal lines provided in the liquid crystal panel 20. In order to distinguish such line-shaped unevenness from backlight unevenness, the reference region is set to a rectangular shape having a small width as shown in FIG. In this case, as shown in FIG. 12, it is determined that the unevenness a and b are included in the reference area, and the unevenness c is determined not to be included in the reference area. Note that the determination unit 5 performs the determination process by rotating the detection unevenness when the detection unevenness and the reference region are overlapped by image processing. Thereby, as shown in FIG. 12, for example, unevenness b extending in a line shape in the vertical direction can be appropriately determined.

Then, it is determined that the unevenness c is not included in the reference area, but since it is determined that the unevenness a and b are included in the reference area (YES in S4), the process proceeds to the correction step (S5).

Next, the same correction processing as in the first embodiment is performed on the unevenness a and b determined to be included in the reference region in the determination step (S4) (S5: correction step), and the processing ends. FIG. 13 is a diagram illustrating a display image based on the image data of the correction gradation.

In the correction step (S5), a process of storing the LUT (correction data) in which the input gradation, the correction gradation, and the correction area (locations of unevenness a and b) are associated is stored in the memory 50 of the liquid crystal display device 10. Do. Thereby, in the liquid crystal display device 10, since the corrected image is displayed with respect to the predetermined input image data, it is possible to suppress the appearance of display unevenness due to panel unevenness.

As for the backlight unevenness (unevenness c), as in the first embodiment, in the correction step (S5), the backlight unit or the light source may be replaced with a normal one, or no processing is performed. Also good.

According to the configuration of the second embodiment, display unevenness (panel unevenness) caused by various signal lines (scanning signal lines, data signal lines, storage capacitor wirings, etc.) provided in the liquid crystal panel 20 can be reduced.

(Example 3)
Next, when image data of a predetermined gradation (31 gradations) is input to the liquid crystal display device before the inspection process (correction process) in the inspection apparatus 1 is performed, the image shown in FIG. 14 is displayed on the display screen. The operation of the inspection apparatus 1 will be described.

The inspection apparatus 1 according to the third embodiment can be configured by combining the first and second embodiments.

That is, after the data input step (S1) and the imaging step (S2) shown in FIG. 2, in the detection step (S3), the brightness corresponding to the 31 gradations in the captured image (FIG. 14) captured by the CCD camera. Detect unevenness in areas represented by different luminance. Here, the irregularities A to D, a, and b in FIG. 14 are detected.

Next, the unevenness A to D, a, b detected in the detection step (S3) is compared with the reference area stored in the memory unit 6 to determine whether the detected unevenness is included in the reference area. (S4: Determination step). Here, among the unevenness shown in FIG. 14, unevenness D is backlight unevenness, unevenness A, B, and C are pin unevenness and suction unevenness, and unevenness a and b are line unevenness caused by scanning signal lines and data signal lines. It is. In the third embodiment, as shown in FIG. 15, the reference area is set in two types (reference area 1 and reference area 2) of a circular shape and a rectangular shape having a small width.

Therefore, the determination unit 5 determines whether or not the detection unevenness is included in either the reference region 1 or the reference region 2 (S4: determination step). For example, the unevenness A is not included in the reference region 2 but is included in the reference region 1, the unevenness a is not included in the reference region 1, but is included in the reference region 2, and the unevenness D is the reference region 1 and the reference region 2. It is not included in any of.

The subsequent processing according to the determination result is the same as in the first embodiment. FIG. 16 is a view showing a display image based on the corrected image data corrected for unevenness A, B, C, a, and b.

According to the configuration of the third embodiment, various display unevenness (pin unevenness, suction unevenness, line unevenness, etc.) due to the liquid crystal panel 20 side can be reduced.

(Example 4)
Next, when image data of a predetermined gradation (31 gradations) is input to the liquid crystal display device before the inspection process (correction process) in the inspection apparatus 1 is performed, the image shown in FIG. 17 is displayed on the display screen. The operation of the inspection apparatus 1 will be described.

After the data input step (S1) and the imaging step (S2) shown in FIG. 2, in the detection step (S3), the captured image (FIG. 17) captured by the CCD camera differs from the luminance corresponding to 31 gradations. The unevenness of the area represented by is detected. Here, the irregularities D and E in FIG. 17 are detected.

Next, the unevennesses D and E detected in the detection process are compared with the reference area stored in the memory unit 6 to determine whether or not the detected unevenness is included in the reference area (S4: determination process). Here, among the unevenness shown in FIG. 17, unevenness D is backlight unevenness, and unevenness E is panel unevenness due to the liquid crystal panel 20 (for example, unevenness due to design errors between a plurality of source drivers). is there. Since such panel unevenness (strip-shaped unevenness) appears all over the vertical direction of the display screen, as shown in FIG. 18, the reference region has a vertical direction larger than the vertical width of the display screen, and the horizontal direction is, for example, one It is set to the width of the area that the source driver is responsible for. Thereby, it can be distinguished from backlight unevenness that appears in the entire horizontal direction of the display screen. Note that if the width of the reference area is set large, correction processing is performed to display unevenness that does not affect the display quality, and this is not preferable from the viewpoint of power consumption and efficiency of the inspection apparatus 1. (Width) is set corresponding to the unevenness to be corrected.

Here, as shown in FIG. 19, it is determined that the unevenness E is included in the reference area, and the unevenness D is not included in the reference area.

The subsequent processing according to the determination result is the same as in the first embodiment. FIG. 20 is a view showing a display image based on the corrected image data corrected for the unevenness E.

According to the configuration of the fourth embodiment, display unevenness caused by the liquid crystal panel 20 side can be reduced.

In the above description of the first to fourth embodiments, the configuration in which the light source of the backlight is provided on the back side of the liquid crystal panel 20 has been described as an example. However, the present invention is not limited to this, and the backlight The present invention can also be applied to a configuration in which the light source is provided on the side surface of the liquid crystal panel 10 (so-called side light type). The backlight unevenness in this configuration is such a luminance distribution that the luminance on the light source side (one side surface of the liquid crystal panel 20) is high on the display screen, and the luminance decreases as the distance from the light source (the other side surface side of the liquid crystal panel 20) increases. appear. In this case, the determination unit 5 of the inspection apparatus 1 performs a process of determining that the luminance distribution unevenness is not included in the reference region. Further, the light source of the backlight includes a fluorescent lamp, an LED, and the like.

(Configuration of liquid crystal display device)
The inspection device 1 according to the present invention can be applied to a conventional general liquid crystal display device. Here, an example of a liquid crystal display device is given.

FIG. 21 is a block diagram showing a schematic configuration of the liquid crystal display device according to the present embodiment. The liquid crystal display device 10 includes a liquid crystal panel (display panel) 20, source drivers 30..., A timing controller 40, and a memory unit 50. The source drivers 30 are mounted on the source substrate 60. The timing controller 40 is a control IC that supplies timing control signals to the source drivers 30..., And the timing controller 40 and the memory unit 50 are provided on the control board 70. The source board 60 and the control board 70 are connected via the connector 61 of the source board 60 and the connector 71 of the control board 70. The timing controller 40 is connected to the source drivers 30 through the connector 71 and the connector 61, and is connected to an external image signal source through the connector 72 of the control board 70.

The memory unit 50 is composed of a storage medium such as a flash memory or an EEPROM. The memory unit 50 stores correction data for correcting display unevenness that occurs on the display screen of the liquid crystal panel 20. The storing process of the correction data in the memory unit 50 is performed in the correction process (S5 in FIG. 2) in the inspection apparatus 1 described above. Here, in the liquid crystal display device 10, the memory unit 50 is provided not on the control substrate 70 but on the source substrate 60.

The memory unit 50 is connected to the timing controller 40 via a connector 61 and a connector 71. The timing controller 40 has a function of correcting display data input from an external image signal source. When the display data is input, the correction data is read from the memory unit 50 on the source substrate 60 and displayed. The corrected display data obtained by correcting the data is generated. The source drivers 30... Generate a gray scale display analog signal based on the corrected display data input from the timing controller 40 and drive the data signal lines of the liquid crystal panel 20. Thereby, an image without display unevenness (panel unevenness) is displayed on the display screen of the liquid crystal panel 20.

Here, according to the configuration of the present liquid crystal display device 10, the following effects can also be obtained. For example, FIG. 22 shows the liquid crystal display device 1 when the control board 70 is replaced with a new control board 70a in response to service. As described above, since the memory unit 50 is provided on the source substrate 60, the memory unit 50 is not removed from the liquid crystal display device 1 even when the control substrate 70 is replaced. Therefore, when the service person replaces the control board during a business trip repair, correction data for correcting display unevenness is stored in the liquid crystal display device 1 without performing work such as attaching the memory unit 50 to the new control board 70a. The state stored in can be maintained. Further, since the source substrate 60 is crimped and connected to the liquid crystal panel 20 via the source drivers 30..., The source substrate 60 is not replaced in the business trip repair service. Therefore, it is possible to reduce the burden on the service person when the control board is replaced or verified.

In the inspection apparatus for a display device according to the present embodiment, when the region is in a line shape extending in the longitudinal direction of the display screen, the determination unit determines that the region is not included in the reference region It can also be.

Thereby, it is possible to avoid the correction processing for the unevenness of the backlight appearing in the longitudinal direction of the display screen.

In the inspection apparatus for a display device according to this embodiment, when the region corresponds to a scanning signal line or a data signal line provided in the display panel, the determination unit determines that the region is the reference region. It can also be set as the structure determined to be contained.

Thereby, unevenness corresponding to the scanning signal line and the data signal line can be reduced.

In the inspection apparatus for a display device according to the present embodiment, the reference area may be rectangular, circular, or elliptical, and may be configured to be smaller than the entire display screen area.

This can reduce panel unevenness such as pin unevenness and suction unevenness.

In the inspection apparatus for a display device according to the present embodiment, the reference region is rectangular, and its long side is shorter than the long side of the display screen, and its short side is shorter than the short side of the display screen. A long configuration can also be used.

In the inspection device for a display device according to the present embodiment, when the region corresponds to the shape of the backlight, the determination unit determines that the region is not included in the reference region. You can also

This makes it possible to avoid correction processing for backlight unevenness.

In the inspection apparatus for a display device according to the present embodiment, when the region corresponds to a display luminance distribution of light incident on the display panel from the backlight, the determination unit It can also be set as the structure determined not to be contained in the said reference area | region.

This makes it possible to avoid correction processing for backlight unevenness.

In the inspection apparatus for a display device according to the present embodiment, the determination unit determines that the region is in a case where the difference between the luminance displayed in the region and the luminance corresponding to the input gradation is equal to or greater than a predetermined value. It can also be configured to determine whether or not it is included in a preset reference area.

Thus, correction processing can be omitted for unevenness that does not affect the display quality, and thus the power consumption and efficiency of the inspection apparatus can be reduced.

In the inspection device for a display device according to the present embodiment, the correction unit stores correction data for correcting image data input to the display device corresponding to the region in the memory unit of the display device. It can also be configured.

Thereby, in the display device, the corrected image is displayed with respect to the predetermined input image data, so that the appearance of display unevenness due to the panel unevenness can be suppressed.

In the inspection method for a display device according to the present embodiment, when the region corresponds to the shape of the backlight, the determination step may be configured such that the region is not included in the reference region. .

In the display device inspection method according to the present embodiment, in the correction step, correction data for correcting image data input to the display device corresponding to the region is stored in a memory unit of the display device. It can also be configured.

Each of the inspection methods can obtain the same effect as that obtained by the configuration of the inspection apparatus.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

The present invention is suitable for, for example, an inspection apparatus for a liquid crystal television.

DESCRIPTION OF SYMBOLS 1 Inspection apparatus 2 Data input part 3 Imaging part 4 Unevenness detection part (detection part)
5 Judgment Unit 6 Memory Unit 7 Correction Unit 10 Liquid Crystal Display Device (Display Device)
20 Liquid crystal panel (display panel)
30 Source Driver 40 Timing Controller 50 Memory Unit 60 Source Board 70 Control Board

Claims

In a display device comprising a display panel and a backlight that emits light to the display panel, the display device is an inspection device that turns on the backlight and inspects the display state of the display panel,
In the inspection image displayed on the display screen, it is determined whether or not an area represented by a brightness different from the target brightness is included in a preset reference area,
When it is determined that the region is included in the reference region, the gradation of the image data corresponding to the region is corrected. On the other hand, when it is determined that the region is not included in the reference region, the region is corrected. An inspection apparatus for a display device, wherein the gradation of the image data corresponding to is not corrected.
In a display device comprising a display panel and a backlight that emits light to the display panel, the display device is an inspection device that turns on the backlight and inspects the display state of the display panel,
A data input unit for inputting inspection image data on the display screen;
An imaging unit that captures a display image displayed on a display screen based on an input gradation of the inspection image data input by the data input unit;
A detection unit that detects an area represented by a luminance different from the luminance corresponding to the input gradation in the captured image captured by the imaging unit;
A determination unit that determines whether or not the region detected by the detection unit is included in a preset reference region;
When the determination unit determines that the region is included in the reference region, the input gradation corresponding to the region is corrected, while when the region is determined not to be included in the reference region An inspection apparatus for a display device, comprising: a correction unit that does not correct an input gradation corresponding to the region.
3. The display device according to claim 2, wherein the determination unit determines that the region is not included in the reference region when the region has a line shape extending in a longitudinal direction of the display screen. Inspection device.
3. The determination unit determines that the region is included in the reference region when the region corresponds to a scanning signal line or a data signal line provided in the display panel. The inspection apparatus of the display apparatus as described in 2.
3. The inspection apparatus for a display device according to claim 2, wherein the reference area is rectangular, circular, or elliptical and is smaller than an entire area of the display screen.
The display according to claim 2, wherein the reference area is rectangular and has a long side shorter than a long side of the display screen and a short side longer than a short side of the display screen. Equipment inspection device.
The determination unit according to any one of claims 2 to 6, wherein when the region corresponds to a shape of the backlight, the determination unit determines that the region is not included in the reference region. Inspection apparatus of the display apparatus of description.
When the region corresponds to a display luminance distribution of light incident on the display panel from the backlight, the determination unit determines that the region is not included in the reference region. The display device inspection apparatus according to any one of claims 2 to 6.
The determination unit determines whether the area is included in a preset reference area when the difference between the luminance displayed in the area and the luminance corresponding to the input gradation is equal to or greater than a predetermined value. 9. The display device inspection apparatus according to claim 2, wherein the determination is performed.
10. The correction unit according to claim 2, wherein the correction unit stores correction data for correcting image data input to the display device corresponding to the region in the memory unit of the display device. The inspection apparatus for a display device according to item 1.
In a display device comprising a display panel and a backlight that irradiates light to the display panel, the display device is inspected to display the display panel by turning on the backlight.
In the inspection image displayed on the display screen, it is determined whether or not an area represented by a brightness different from the target brightness is included in a preset reference area,
When it is determined that the region is included in the reference region, the gradation of the image data corresponding to the region is corrected. On the other hand, when it is determined that the region is not included in the reference region, the region is corrected. A method for inspecting a display device, wherein the gradation of the image data corresponding to is not corrected.
In a display device comprising a display panel and a backlight that irradiates light to the display panel, the display device is inspected to display the display panel by turning on the backlight.
A data input process for inputting inspection image data on the display screen;
An imaging step of capturing a display image displayed on the display screen based on the input gradation of the inspection image data input in the data input step;
A detection step of detecting an area represented by a luminance different from the luminance corresponding to the input gradation in the captured image captured in the imaging step;
A determination step of determining whether or not the region detected in the detection step is included in a preset reference region;
In the determination step, when it is determined that the region is included in the reference region, the input gradation corresponding to the region is corrected, while when it is determined that the region is not included in the reference region And a correction step in which the input gradation corresponding to the region is not corrected.
13. The method for inspecting a display device according to claim 12, wherein when the area corresponds to a shape of the backlight, the determination step determines that the area is not included in the reference area. .
14. The correction step according to claim 12, wherein correction data for correcting image data input to the display device corresponding to the region is stored in a memory unit of the display device. Display device inspection method.