KR20160031142A - Mura Detecting Device - Google Patents

Abstract

The present invention relates to a mura detecting device automatically inspecting distortion of a picture quality such as a stain defect of a display device. According to an embodiment of the present invention, the mura detecting device inspects: a test image supply unit generating a plurality of test image data displayed in a different gray, and supplying the generated test image data to a display device; a brightness measuring unit photographing a test image displayed on a screen of the display device, and generates brightness data of a whole image; and a mura detecting unit dividing the screen of the display device into a plurality of blocks, and connecting the blocks of a horizontal line to generate the mura data in a plurality of line units.

Description

Mura Detecting Device [0001]

The present invention relates to a mura detection apparatus for automatically checking an image quality distortion such as a spot defect of a display device.

As mobile electronic devices such as mobile communication terminals and notebook computers are developed, there is an increasing demand for flat panel display devices applicable thereto.

Examples of flat panel display devices include a liquid crystal display device (LCD), a field emission display device (FED), a plasma display panel (PDP), and an organic light emitting diode (OLED) light emitting diode display device) has been developed.

Of these flat panel display devices, a self-emission type liquid crystal display device has been most widely applied because it has advantages of response speed, high resolution and large screen.

As a liquid crystal display device (LCD) becomes larger in size, mura defects, that is, stain defects and image quality distortions are increasing in size and frequency. The term mura refers to a speckle in Japanese, and means a defect in which the luminance of a specific area is displayed unevenly when the entire screen is displayed at a constant gray scale.

FIG. 1 is a view showing a method of detecting the unevenness of a display device according to the related art.

Referring to FIG. 1, a test image for detecting dust is displayed on a display panel 10, and an engineer checks whether or not each part of the screen has been blurred while viewing a screen displayed on the display panel 10 with the naked eye.

The display panel 10 on which the dust is generated is discarded or the display panel 10 is transferred to the repairing process when the level of the dust can be repaired.

Such a method for detecting the unevenness according to the related art can not obtain objective uneven data because the inspection is performed with the naked eye of the engineer. Particularly, the detection accuracy of the mura by the engineer's eyes may differ depending on the skill of the engineer, and there is a problem that the deviation of the mura detection increases with the larger surface.

In addition, there is a problem that deviation of defects due to irregularities occurs depending on the engineer, which makes it impossible to detect irregularities of uniform quality. In addition, even if the same engineer detects the unevenness, the unevenness detection result may be different every time of the inspection, and there is a problem that it is impossible to detect the unevenness of the uniform quality.

Even if the detection of the mura is carried out while a certain standard is set, it is impossible to obtain quantized detection data quantized by broadly distributing the criterion for discriminating the mura, resulting in a problem of deteriorating the mass production quality of the display device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a mura detection device capable of enhancing the mura detection performance of a display device.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a mura detection device capable of generating objective data, quantified data, and quantized data.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is a technical object to provide a mura detection device capable of automatically detecting mura.

Other features and advantages of the invention will be set forth in the description which follows, or may be obvious to those skilled in the art from the description and the claims.

According to an aspect of the present invention, there is provided a mura detection apparatus including: a test image supply unit configured to generate a plurality of test image data displayed in different gray levels and supply the same to a display device; A brightness measuring unit for sensing a test image displayed on a screen of the display device and generating brightness data of the entire image; And a spreadsheet detector for dividing a screen of the display device into a plurality of blocks and connecting blocks of the horizontal lines to generate spread data in units of a plurality of lines.

According to the solution of the above problem, the mura detection apparatus according to the embodiment of the present invention can enhance the mura detection performance of the display apparatus.

According to the means for solving the above problems, the mura detection apparatus according to the embodiment of the present invention can generate objection, quantification and quantized mura data.

According to the solution of the above problem, the mura detection apparatus according to the embodiment of the present invention can automatically detect mura.

According to the solution of the above problem, the mura detection apparatus according to the embodiment of the present invention can clearly confirm whether or not mura has occurred in the screen of the display device and in which part of the whole screen the mura has occurred.

According to the means for solving the above problems, the mura detection apparatus according to the embodiment of the present invention can confirm the degree of mura in the area where mura is generated by the mura data quantified and quantified, Can be utilized as raw data.

According to the solution of the above problem, the mura detection apparatus according to the embodiment of the present invention can generate the luminance correction data to be applied to the pixels in the area where the mura is generated based on the mura data when the degree of mura does not occur to a great extent And the brightness data is precisely generated, so that the brightness correction data can be precisely generated and the brightness can be corrected.

According to the solution of the above problem, the mura detection apparatus according to the embodiment of the present invention can automatically detect mura, thereby reducing the tact time required for mura detection.

Other features and effects of the present invention may be newly understood through the embodiments of the present invention in addition to the features and effects of the present invention mentioned above.

FIG. 1 is a view showing a method of detecting the unevenness of a display device according to the related art.
2 is a view showing a mura detection apparatus according to an embodiment of the present invention.
FIG. 3 is a diagram illustrating a leakage detection unit according to an embodiment of the present invention.
FIGS. 4 to 6 are diagrams illustrating a method of detecting a mura using a mura detection apparatus according to an embodiment of the present invention.

The meaning of the terms described herein should be understood as follows.

The word " first, "" second," and the like, used to distinguish one element from another, are to be understood to include plural representations unless the context clearly dictates otherwise. The scope of the right should not be limited by these terms. It should be understood that the terms "comprises" or "having" does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. It should be understood that the term "at least one" includes all possible combinations from one or more related items. For example, the meaning of "at least one of the first item, the second item and the third item" means not only the first item, the second item or the third item, but also the second item and the second item among the first item, Means any combination of items that can be presented from more than one. The term "on" means not only when a configuration is formed directly on top of another configuration, but also when a third configuration is interposed between these configurations.

The liquid crystal display device has been developed in various ways such as TN (Twisted Nematic) mode, VA (Vertical Alignment) mode, IPS (In Plane Switching) mode and FFS (Fringe Field Switching) mode according to a method of adjusting the arrangement of liquid crystal layers.

In the TN mode and the VA mode, a pixel electrode is formed on a lower substrate and a common electrode is formed on an upper substrate (color filter array substrate) to adjust the alignment of the liquid crystal layer through a vertical electric field.

In the IPS mode and the FFS mode, a pixel electrode and a common electrode are disposed on a lower substrate, and the alignment of the liquid crystal layer is adjusted by an electric field between the pixel electrode and the common electrode.

In the IPS mode, the pixel electrode and the common electrode are alternately arranged in parallel to each other to generate a horizontal electric field between the two electrodes to adjust the alignment of the liquid crystal layer. In such an IPS mode, the alignment of the liquid crystal layer in the upper portion of the pixel electrode and the common electrode is not adjusted, and the transmittance of light is reduced in the region.

The FFS mode is designed to solve the shortcomings of the IPS mode. In the FFS mode, the pixel electrode and the common electrode are formed so as to be spaced apart with an insulating layer therebetween. At this time, one electrode is formed in a plate shape or a pattern and the other electrode is formed in a finger shape, and the arrangement of the liquid crystal layer is controlled through a fringe field generated between the electrodes Method.

In the present invention, the liquid crystal display device can be applied to both the vertical electric field method (TN mode, VA mode) and the horizontal electric field method (IPS mode, FFS mode) without any mode restriction. In the following description, As an example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a mura detection apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings.

2 is a view showing a mura detection apparatus according to an embodiment of the present invention. The present invention relates to a mura detection apparatus, and a driving apparatus of a display panel not related to the mura detection apparatus is not shown in Fig.

2, the mura detection apparatus 200 according to an embodiment of the present invention includes a test image supply unit 210, a luminance measurement unit 220, and a mura detection unit 230.

The test image supply unit 210 generates a plurality of test image data, each of which is displayed in different gray, and supplies a plurality of test image data to the display device 100. At this time, each of the plurality of test image data can be generated in the range of 0 gray to 255 gray in the average gray of the entire screen.

For example, the test image supply unit 210 may supply the first test image data whose average gray of the entire screen is 32 gray, the second test image data whose average gray of the entire screen is 64 gray, the average gray of the entire screen is 96 gray The third test video data, the fourth test video data whose average gray of the entire screen is 128 gray, the fifth test video data whose average gray of the entire screen is 192 gray, and the sixth test video data whose average gray of the entire screen is 255 gray . Then, the test image supply unit 210 may supply the first to sixth test image data to the display device 100.

Here, the test image supply unit 210 may sequentially arrange two or more pieces of test image data among the first to sixth test image data, and supply the two or more pieces of test image data to the display device 100.

In the present invention, the average brightness of the test image data may be set in the range of 0 to 255 gray, 32, 64, 96, 128, 192, 255 gray, 192, 255 test gray level data other than gray.

The brightness measuring unit 220 captures a test image displayed on the screen of the display device 100, generates brightness data of the entire test image, and transmits the brightness data of the test image to the brightness detecting unit 230.

Here, the brightness measuring unit 220 may generate brightness data of the entire screen of the first to sixth test images according to the first to sixth test image data, and may transmit the brightness data of the test image to the brightness detecting unit 230 have. The brightness measuring unit 220 may be a digital camera or an image sensor.

FIG. 3 is a diagram illustrating a leakage detection unit according to an embodiment of the present invention.

Referring to FIG. 3, the brightness detector 230 of the present invention divides the entire screen of the display device into a plurality of blocks, generates a luminance average value and a Gaussian average value in units of lines in which the blocks are connected in the horizontal direction, And generates mura data for discrimination. The brightness detection unit 230 includes a brightness data detection unit 232, a brightness average value calculation unit 234, a Gaussian average value calculation unit 236, and a mura data generation unit 238.

FIGS. 4 to 6 are diagrams illustrating a method of detecting a mura using a mura detection apparatus according to an embodiment of the present invention.

Referring to FIGS. 3 and 4, the entire screen of the display device 100 is imaged using the brightness measuring unit 220, and the brightness of the entire screen is detected (S10).

Then, the luminance data detector 232 divides the entire screen of the display device 100 into a plurality of blocks, and detects the luminance of each block based on the luminance detection result of the entire screen (S20).

5, the luminance data detector 232 divides the entire screen of the display device 100 into a total of 6,912 blocks divided into 96 horizontal lines and 72 vertical lines, and 6,912 The luminance of each block is detected.

Then, the luminance average value calculation unit 234 connects the 6,912 blocks in the horizontal line unit, and calculates the luminance average value of each of the 72 lines based on the luminance of each of the 6,912 blocks (S30).

Then, the Gaussian average value calculation unit 236 generates linear Gaussian data for each of the 72 lines based on the detection results of the luminance of each of 6,912 blocks (S40).

Subsequently, the Gaussian average value calculation unit 236 calculates a Gaussian average value of each of the 72 lines (S50).

Then, the mura data generator 238 calculates the difference between the luminance average value of each of the 72 lines calculated in S30 and the Gaussian average value of each of the 72 lines calculated in S50 (S60). Thus, a quantized luminance band value is calculated for each of the 72 lines.

Specifically, referring to Fig. 6, as shown in Fig. 6A, the mura data generator 238 generates an average luminance graph of each of the 72 lines. Then, as shown in Fig. 6 (b), a Gaussian average graph of each of the 72 lines is generated.

Then, the mura data generator 238 convolutes the Gaussian average graph to generate a filtered luminance graph as shown in FIG. 6 (c). Then, the difference between the luminance average graph of each of the 72 lines and the filtered luminance graph is calculated, and the quantized luminance band value for each of the 72 lines is calculated. In the above description, the entire screen is divided into 96 horizontal lines and 72 vertical lines to divide the entire screen into 6,912 blocks, which is an example.

If the shape of the graph is shown as a peak like the area A in FIG. 6 (c), the difference between the luminance average value and the Gaussian average value is large, and it can be judged that such a region is generated.

On the other hand, when the shape of the graph is linearly shaped with a gentle slope without peak, as in the area B of FIG. 6 (c), the difference between the luminance average value and the Gaussian average value is small. .

Then, the mura data generator 238 performs a generalization algorithm to reduce errors of quantized brightness bands for each of the 72 lines, and generates mura data based on the luminance band values (S70).

In the case where the mura detection is performed under the same condition, the mura data generated by the mura data generation unit 238 can obtain the same result value and obtain the objective mura data.

In addition, it is possible to generate mura data that is quantified and quantized for each of a plurality of lines, thereby enhancing the mura detection performance of the display device.

It is possible to clearly confirm whether or not the screen of the display device has been blurred and in which part of the entire screen blur occurred by using the blur detection unit 230 of the blur detection apparatus 200 according to the embodiment of the present invention.

In addition, since the degree of mura in the region where mura is generated can be confirmed by mura data quantified and quantified, there is an advantage that it can be utilized as low data for improvement work of the manufacturing process for removing mura.

In the case where the magnitude of the magnitude does not occur very much, the brightness correction data to be applied to the pixels in the area where the magnification is generated based on the magnification data can be generated, and the magnification data is precisely generated, There is an advantage that the mura can be corrected.

In addition, the mura detection apparatus 200 according to the embodiment of the present invention can perform mura detection automatically using the test image supply unit 210, the luminance measurement unit 220, and the mura detection unit 230, It is possible to reduce the tact time.

The gray level detection unit of the gray level detection apparatus according to the embodiment of the present invention includes a brightness data detection unit for detecting the brightness of each of the plurality of blocks.

The mura detection unit of the mura detection apparatus according to the embodiment of the present invention includes a luminance average value calculation unit for detecting an average luminance value of the plurality of lines.

The mura detection unit of the mura detection apparatus according to an embodiment of the present invention includes a Gaussian average value calculation unit for generating linear Gaussian data for each of the plurality of blocks and a Gaussian average value of the plurality of lines.

The mura detection unit of the mura detection apparatus according to the embodiment of the present invention calculates the plurality of luminance band values for each line based on the difference between the average luminance value and the Gaussian average value of the plurality of lines, And a mura data generation unit for outputting the band value as mura data.

The unevenness data generating unit of the unevenness detecting apparatus according to an embodiment of the present invention generates a filtered luminance graph by convoluting an average luminance graph and a Gaussian average graph of the plurality of lines, And calculates a plurality of luminance band values for each line by calculating a difference between the filtered luminance graphs.

The test image supply unit of the mura detection apparatus according to the embodiment of the present invention sequentially arranges two or more test image data and supplies them to the display device.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

200: mura detection device
210: Test image supply unit
220: luminance measurement unit
230:
232: luminance data detector
234: luminance average value calculating section
236: Gaussian average value calculating unit
238:

Claims (7)

A test image supply unit for generating a plurality of test image data displayed in different gray and supplying the same to a display device;
A brightness measuring unit for sensing a test image displayed on a screen of the display device and generating brightness data of the entire image; And
And a non-uniformity detector for dividing a screen of the display device into a plurality of blocks and connecting blocks of the horizontal lines to generate non-uniform data in units of a plurality of lines. The method according to claim 1,
The above-
And a luminance data detector for detecting the luminance of each of the plurality of blocks. 3. The method of claim 2,
The above-
And a luminance average value calculation unit for calculating an average luminance value of the plurality of lines. The method of claim 3,
The above-
And a Gaussian average value calculation unit for generating linear Gaussian data for each of the plurality of blocks and a Gaussian average value of the plurality of lines. 5. The method of claim 4,
Calculating a luminance band value for each of the plurality of lines based on a difference between an average luminance value and a Gaussian average value of the plurality of lines,
And outputting the plurality of line-by-line luminance band values as non-uniform data. 6. The method of claim 5,
Wherein the spread data generator comprises:
Generating a filtered luminance graph by convoluting an average luminance graph and a Gaussian average graph of the plurality of lines,
And calculates a difference between the luminance average graph of the plurality of lines and the filtered luminance graph to calculate the plurality of luminance band values for each line. The method according to claim 1,
Wherein the test image supply unit sequentially arranges two or more pieces of test image data and supplies the two or more pieces of test image data to the display device.

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