KR20160046606A - Apparatus for compensating image data of display device - Google Patents

Abstract

Provided is an apparatus for compensating image data of a display device which can prevent a brightness fault in an image displayed in a display panel due to a stain having a shape of a band such as a stitch. The apparatus for compensating image data generates compensation data and a compensation code in pixel unit from brightness level information for each of multiple sub pixels of the display panel to compensate a gradation level of image data outputted to the display panel.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to an image data compensating apparatus, and more particularly, to an image data compensating apparatus for a display apparatus that can compensate image data applied to a display apparatus to prevent a luminance defect due to a stitch spot or the like.

Flat panel displays (FPDs) have been replaced with conventional cathode ray tube (CRT) display devices to provide a compact and lightweight display device for portable computers such as notebook computers, PDAs, and mobile phone terminals as well as monitors of desktop computers Lt; RTI ID = 0.0 > system. ≪ / RTI >

Currently available flat panel display devices include a liquid crystal display (LCD), a plasma display panel (PDP), and an organic light emitting diode (OLED) display. The dual liquid crystal display device is attracting attention as a display device used for a mobile device, a computer monitor, and an HDTV due to advantages such as excellent visibility, easy thinning, low power and low heat generation.

A liquid crystal display forms various patterns on a substrate constituting a display panel through a photolithography process. In this process, an exposure process using an exposure apparatus is performed. A typical exposure process proceeds by aligning one mask onto a substrate and exposing the entire substrate with a single shot.

Recently, as the liquid crystal display becomes larger in size, the exposure process can not proceed to a single shot. Accordingly, the exposure process for the large-area liquid crystal display device proceeds to a divided exposure process in which the substrate to be patterned is divided into a plurality of regions and the divided regions are respectively exposed.

FIG. 1A is a view for explaining a divisional exposure process in a conventional liquid crystal display device, and FIG. 1B is a diagram showing an exposure region according to a divisional exposure process.

1A, in the conventional large-area liquid crystal display device, the substrate 10 is divided into a plurality of exposure regions 21a to 21c, and each exposure process is performed on the divided exposure regions 21a to 21c. The exposure regions A, B, and C, that is, the pattern regions are formed on the substrate 10 by such a divided exposure process.

On the other hand, the boundaries of the shot regions, that is, the boundaries of the A, B, and C pattern regions by the divided exposure process are accumulated together as the patterns are formed by accumulating layers. This results in a difference in aperture ratio and parasitic capacitance between the pattern regions A, B, and C.

The difference in aperture ratio and parasitic capacitance between such pattern regions causes a brightness difference between adjacent pattern regions as shown in FIG. 1B. The difference in brightness between the pattern areas causes strip-shaped stitch spots in the longitudinal or transverse shape on the screen of the liquid crystal display device. Stitch unevenness causes a luminance defect of the liquid crystal display device.

In a conventional liquid crystal display device, a video data compensation method for increasing or decreasing a level of video data output from a timing controller (not shown) or the like to a display panel, that is, a gradation level of video data, Respectively.

However, the conventional image data compensation method can not know the position of the smear generated on the display panel, and thus compensates the gradation level of the image data applied to all the subpixels of the display panel, that is, all the R, G, and B subpixels. Accordingly, in a conventional liquid crystal display device, a high capacity memory is required to store compensation data for compensation of image data, thereby increasing the manufacturing cost of the liquid crystal display device.

An object of the present invention is to provide a video data compensation apparatus of a display device which can compensate image data while minimizing a capacity increase of a memory for storing compensation data, thereby preventing a luminance defect caused by stains such as stitches.

According to an aspect of the present invention, there is provided an image data compensating apparatus including a compensation data generating unit, a compensation code generating unit, and a compensating unit.

The compensation data generation unit generates compensation data on a pixel basis from the luminance level information for each of a plurality of subpixels of the display panel.

The compensation code generation unit generates compensation codes in pixel units from the luminance level information for each of the plurality of subpixels of the display panel.

The compensation unit compensates the gradation level of the image data output to the display panel according to the compensation data and the compensation code.

The image data compensating apparatus of the display apparatus according to the present invention compensates the image data applied to each subpixel of the display panel at least once according to the pixel level information or the exposure width information of all the subpixels of the display panel, Or the like is compensated for twice or more, it is possible to prevent a luminance defect from occurring in the image displayed on the display panel due to the smear.

In addition, the image data compensating apparatus can accurately determine the position even if the stitch smudges occur in the subpixels arranged in one line on the same line in the display panel, thereby enhancing the reliability of the image data compensation.

In addition, the image data compensating apparatus generates and stores the compensation data and the compensation code on a pixel-by-pixel basis, thereby reducing the capacity of the memory for compensation data storage as compared with the related art.

1A is a view for explaining a divided exposure process in a conventional liquid crystal display device.
1B is a view showing an exposure area according to a division exposure process.
2 is a view showing a display device according to an embodiment of the present invention.
3 is a diagram showing a configuration of the data compensator shown in FIG.
4 is a flowchart illustrating an image data compensation method using the data compensator shown in FIG.
5 is a flowchart illustrating a method of generating a compensation code according to another embodiment of the present invention.
6 is a flowchart illustrating an image data compensation method of the compensation unit shown in FIG.
Figs. 7A to 7C and Figs. 8A to 8C are operation examples of the data compensator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a video data compensation apparatus of a display apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

2 is a view showing a display device according to an embodiment of the present invention.

2, the display device 100 according to the present embodiment may be a liquid crystal display device and includes a display panel 110, a gate driver 120, a data driver 130, and a timing controller 140 .

The display panel 110, that is, the liquid crystal panel may include an array substrate (not shown), a color filter substrate (not shown), and a liquid crystal layer (not shown) interposed between the two substrates.

The array substrate may include pixel regions defined for each of the intersections of the plurality of gate lines GL1 to GLn, the plurality of data lines DL1 to DLm and the gate lines GL1 to GLn and the data lines DL1 to DLm. have. A thin film transistor (TFT), a liquid crystal capacitor Clc, and a storage capacitor Cst may be formed in each pixel region of the array substrate.

The color filter substrate may include a color filter (not shown) corresponding to each pixel region of the array substrate. The color filter may be formed of R, G, B, or R, G, B, Each of the color filters may correspond to each of the pixel regions of the array substrate to form one pixel. For example, each of the R, G, and B color filters may correspond to three pixel regions of the array substrate to form one pixel. At this time, each of the pixel regions corresponding to each of the R, G, and B color filters may form a sub-pixel.

The display panel 110 may be driven by a driving signal, such as a gate signal and a data signal, provided from the gate driver 120 and the data driver 130, which will be described later.

For example, when gate signals are supplied from the gate driver 120 to the plurality of gate lines GL1 to GLn of the display panel 110, the thin film transistors TFT connected to the gate lines GL1 to GLn are turned on. The data signal supplied from the data driver 130 to the plurality of data lines DL1 to DLm is applied to the liquid crystal capacitor Clc and the storage capacitor Cst through the thin film transistor TFT of the pixel to display an image .

The array substrate and the color filter substrate of the display panel 110 are subjected to photolithography to form respective patterns such as gate lines GL1 to GLn, data lines DL1 to DLm, thin film transistors (TFT) A photolithography process is performed. The photolithography process may include a deposition process and an exposure process.

As the display panel 110 is made larger, the exposure process during the photolithography process can be performed a number of times. For example, an array substrate on which a metal thin film or the like is deposited may be divided into a plurality of regions, and each of the divided regions may be subjected to an exposure process to form a pattern on the array substrate. As described above, when the display panel 110 is manufactured in a number of exposure steps, a difference in aperture ratio and parasitic capacitance may occur between patterns formed in the respective divided regions. This difference causes a difference in brightness between the divided regions, and thus band-like unevenness such as a stitch or the like appears.

Accordingly, the display apparatus 100 of the present embodiment compensates the gradation level of the image data RGB 'according to presence or absence of smear through the image data compensating apparatus, that is, the data compensating unit 150, to be output to the display panel 110 can do. The data compensation unit 150 will be described later in detail.

The gate driver 120 may generate a gate signal according to the gate control signal GCS provided from the timing controller 140. [ The gate signal may be sequentially output to the plurality of gate lines GL1 to GLn of the display panel 110. [

The data driver 130 may generate a data signal having a positive / negative polarity from the image data according to the data control signal DCS provided from the timing controller 140. The data signal may be output to the plurality of data lines DL1 to DLm of the display panel 110. [ Here, the image data supplied from the timing controller 140 to the data driver 130 may be the compensated image data RGB '' having the gradation level compensated by the data compensator 150.

The timing controller 140 may generate a gate control signal GCS and a data control signal DCS from a control signal CNT provided from an external system (not shown). The gate control signal GCS may be output to the gate driver 120 and the data control signal DCS may be output to the data driver 130.

The gate control signal GCS may include a gate start pulse GSP, a gate shift clock GSC, an output enable signal GOE, and the like. The data control signal DCS may include a source start pulse SSP, a source sampling clock SSC, an output enable signal SOE, a polarity control signal POL, and the like.

The timing controller 140 may process the image signal RGB provided from the external system to the resolution of the display panel 110 to generate the rearranged image data RGB '.

The timing controller 140 may further include a data compensator 150. The data compensating unit 150 compensates the gradation level of the image data RGB 'according to the information of the display panel 110 provided from the outside, for example, the brightness level information LI or the exposure width information SI, RGB "). The compensated image data RGB '' may be output to the data driver 130 together with the data control signal DCS.

3 is a diagram showing a configuration of the data compensator shown in FIG.

2 and 3, the data compensation unit 150 may include a compensation data generation unit 151, a compensation code generation unit 153, and a compensation unit 155.

The compensation data generation unit 151 can generate and output compensation data (CD) for each pixel of the display panel 110 in accordance with the brightness level information LI provided from the outside. The brightness level information LI may be information on the subpixel-generated information, i.e., information on the brightness level of each of a plurality of subpixels of the display panel 110. [

The compensation data generation unit 151 calculates the gradation difference of each of the plurality of subpixels from the luminance level information LI and generates the compensation data CD in pixel units of the display panel 110 according to the calculated gradation difference . For example, the compensation data generation unit 151 may generate one compensation data (CD) for one pixel including R, G, and B sub-pixels.

The compensation code generating unit 153 can generate and output a compensation code of the pixel unit of the display panel 110 in accordance with the luminance level information LI.

The compensation code generation unit 153 calculates the gradation difference of each of a plurality of subpixels from the luminance level information LI and generates a compensation code in pixel units of the display panel 110 according to the calculated gradation difference . For example, the compensation code generation unit 153 may generate one compensation code for one pixel including R, G, and B sub-pixels.

The compensation code generating unit 153 can generate a compensation code composed of binary numbers of 2 or more bits. In addition, the compensation code generating unit 153 may generate a compensation code that defines a position of the R, G, and B sub-pixels in a case where the gradation difference of one pixel has a different gradation.

In addition, the compensation code generating unit 153 may generate a compensation code in units of pixels in accordance with the exposure information SI provided from the outside instead of the luminance level information LI. The exposure information SI refers to information on the exposure width of the exposure apparatus used in the exposure process for the display panel 110. [

The compensation code generation unit 153 can generate a compensation code of 2 bits or more that predicts a position at which spotting will occur in the display panel 110 according to the exposure width information SI and defines a predicted position.

The compensation unit 155 compensates the gradation level of the image data RGB 'according to the compensation data CD and the compensation code Code provided from the compensation data generation unit 151 and the compensation code generation unit 153, It is possible to output the video data RGB ''. The compensated image data RGB '' may be data in which the gradation level is increased or decreased in comparison with the original image data RGB '.

The compensation unit 155 may output the compensated image data RGB '' by compensating the gradation level of the image data RGB 'at least twice using the compensation data CD and the compensation code Code .

4 is a flowchart illustrating an image data compensation method using the data compensator shown in FIG. Figs. 7A to 7C and Figs. 8A to 8C are operation examples of the data compensator.

7A and 8A, the display panel 110 includes a plurality of pixels P1 to P3 arranged in one direction, for example, a lateral direction, and each pixel includes a plurality of sub-pixels, for example, R, G , And B subpixels R1 to B3.

2 to 4, test image data may be provided to the display panel 110 from the timing controller 140 (S10).

The timing controller 140 generates test image data having a predetermined gradation level and outputs the generated test image data to a plurality of data lines DL1 to DLm of the display panel 110 through the data driver 130 . Here, the test image data may be provided to each of all the subpixels R1 to B3 of the display panel 110 in the same manner.

Next, an image of an entire surface of the display panel 110 can be picked up using an external device, such as a camera or the like, and the luminance of the display panel 110 can be measured from the picked-up image. Then, the brightness level information LI corresponding to the measured brightness can be generated (S20). The brightness level information (LI) may be provided to the data compensating unit (150).

The brightness level information LI may be information on the brightness levels of all the subpixels R1 to B3 of the display panel 110 as described above. For example, when the display apparatus 100 is an FHD (Full HD), the brightness level information LI is information on the brightness levels of all the subpixels of the display apparatus 100, that is, 1920 * 1080 * Lt; / RTI >

7A and 8A, test image data having a 20-gradation level is applied from the timing controller 140 to the display panel 110, and then the image of the front face of the display panel 110 is taken out of the display panel 110, The brightness level information LI can be generated by measuring the brightness of each of the plurality of subpixels R1 to B3 of the display unit 110. [

For example, as shown in FIG. 7A, the first pixel P1 of the display panel 110 has the same luminance as the R, G, and B sub-pixels R1, G1, and B1, LI) may be generated. Since the R, G, and B subpixels R2, G2, and B2 have the same luminance, the second pixel P2 can generate 12, 2, and 2 luminance level information LI. Since the R, G, and B subpixels R3, G3, and B3 all have the same luminance, the third pixel P3 can generate 8, 8, and 8 luminance level information LI.

As shown in FIG. 8A, the first pixel P1 of the display panel 110 has the same luminance as the R, G, and B sub-pixels R1, G1, and B1, LI) may be generated. Since the R, G, and B subpixels R2, G2, and B2 have the same luminance, the second pixel P2 can generate 12, 2, and 12 luminance level information LI. Since the R, G, and B subpixels R3, G3, and B3 all have the same luminance, the third pixel P3 can generate 8, 8, and 8 luminance level information LI.

The compensation data generation unit 151 of the data compensation unit 150 can calculate the gradation difference GD for each of the plurality of subpixels R1 to B3 of the display panel 110 from the provided brightness level information LI (S30). The gradation difference GD can be calculated from the difference between the gradation level of the test image data and the luminance level information LI of each of the sub-pixels R1 to B3. The compensation data generation section 151 can calculate the gradation difference GD with respect to all the subpixels R1 to B3 of the display panel 110. [

The compensation code generating unit 153 may also calculate the gradation difference GD for each of the subpixels R1 to B3 of the display panel 110 from the luminance level information LI in the same manner.

7A, since the gradation level 20 of the test image data and the luminance level information LI of the first pixel P1 are 12, 12, and 12, the gradation difference GD (GD) of the first pixel P1 ) Can be calculated as 8, 8, and 8. Since the luminance level information LI of the second pixel P2 is 12, 2, and 2, the gradation difference GD of the second pixel P2 can be calculated as 8, 18, and 18. Since the luminance level information LI of the third pixel P3 is 8, 8, and 8, the gradation difference GD of the third pixel P3 can be calculated as 12, 12, and 12.

8A, since the gradation level 20 of the test image data and the luminance level information LI of the first pixel P1 are 12, 12, and 12, the gradation difference GD (GD) of the first pixel P1 ) Can be calculated as 8, 8, and 8. Since the luminance level information LI of the second pixel P2 is 12, 2, and 12, the gradation difference GD of the second pixel P2 can be calculated as 8, 18, and 8. Since the luminance level information LI of the third pixel P3 is 8, 8, and 8, the gradation difference GD of the third pixel P3 can be calculated as 12, 12, and 12.

The compensation data generation unit 151 can generate compensation data CD in units of pixels from the calculated gradation difference GD (S40). Here, the compensation data CD may be generated from an average value or a difference value of the gradation difference GD of each of the calculated sub-pixels R 1 to B 3.

7A, since the gradation difference GD of the first pixel P1 is 8, 8, and 8, the compensation data CD for the first pixel P1 is the gradation difference GD of the gradation difference GD, Can be generated with an average value of 8. Since the gradation difference GD of the second pixel P2 is 8, 18, and 18, the compensation data CD for the second pixel P2 is the difference between the R subpixel R2 and the G subpixel G2 The difference value GD of the gradation difference GD can be generated. Since the gradation difference GD of the third pixel P3 is 12, 12 and 12, the compensation data CD for the third pixel P3 can be generated with the average value 12 of the gradation difference GD.

8A, since the gradation difference GD of the first pixel P1 is 8, 8, and 8, the compensation data CD for the first pixel P1 is the gradation difference GD of the gradation difference GD, Can be generated with an average value of 8. Since the gradation difference GD of the second pixel P2 is 8, 18, and 8, the compensation data CD for the second pixel P2 is the same as that of the R subpixel R2 and the G subpixel G2 A difference value of the gradation difference GD or a difference value 10 of the gradation difference GD of the G subpixel G2 and the B subpixel B2. Since the gradation difference GD of the third pixel P3 is 12, 12 and 12, the compensation data CD for the third pixel P3 can be generated with the average value 12 of the gradation difference GD.

The compensation data generation unit 151 may store the generated compensation data CD in an internal memory (not shown). Then, the compensation data (CD) corresponding to the image data compensation operation of the compensation unit 155 can be selected and output to the compensation unit 155.

As described above, in the display device 100 of the present invention, the capacity of the memory for storing the compensation data can be reduced in comparison with the conventional display device by generating and storing compensation data (CD) in units of pixels.

For example, in the case where the display apparatus 100 is the FHD, since the present invention requires 1920 * 1080 pieces of compensation data (CD), the capacity of the memory can be reduced to about 1920 * 1080 * Can be reduced to 1/3.

The compensation code generating unit 153 may generate a compensation code Code in units of pixels from the calculated gradation difference GD (S50). Here, the compensation code Code may be generated according to the positions of at least two subpixels having different gradation differences GD among a plurality of subpixels of one pixel.

7A, since the gradation difference GD of the first pixel P1 is 8, 8, and 8, the compensation code for the first pixel P1 is generated as 00 . Since the gradation difference GD of the second pixel P2 differs from 8, 18 and 18, the compensation code Code for the second pixel P2 is the R subpixel R2 and the G subpixel G2 ) According to the gradation difference (GD). Since the gradation difference GD of the third pixel P3 is equal to 12, 12, and 12, the compensation code Code for the third pixel P3 can be generated as 00.

8A, since the gradation difference GD of the first pixel P1 is 8, 8, and 8, the compensation code for the first pixel P1 is generated as 000 . Since the gradation difference GD of the second pixel P2 differs from 8, 18, and 8, the compensation code for the second pixel P2 is the R subpixel R2 and the G subpixel G2 ) According to the gradation difference GD of the G subpixel G2 or the gradation difference GD of the G subpixel G2 and the B subpixel B2. Since the gradation difference GD of the third pixel P3 is equal to 12, 12 and 12, the compensation code Code for the third pixel P3 can be generated to be 000.

That is, the compensation code generating unit 153 has a value of 0 if the gradation difference of each subpixel in one pixel of the display panel 110 is 0, and a value of 1 Lt; / RTI >

On the other hand, the compensation code generating unit 153 may generate the same compensation code for each of a plurality of pixels arranged on the same line in one direction of the display panel 110.

For example, the compensation code generating unit 153 may generate the same compensation code for a plurality of pixels arranged in the same vertical line direction of the display panel 110. [ The compensation code generating unit 153 may generate the same compensation code for a plurality of pixels arranged in the same horizontal line direction of the display panel 110. [ This is because band-like unevenness such as stitches appearing on the display panel 110 appears only in one direction, e.g., the horizontal direction or the vertical direction, of the display panel 110. [

The compensation code generation unit 153 may store the generated compensation code in units of pixels in an internal memory (not shown). The corresponding compensation code may be selected and output to the compensation unit 155 in accordance with the image data compensation operation of the compensation unit 155.

As described above, in the display device 100 of the present invention, a compensation code is generated for each pixel, and the same compensation code is generated for a plurality of pixels arranged in the same line on the display panel 110, The capacity of the memory for storing the compensation code can be reduced.

For example, when the display device 100 is an FHD, since the present invention requires 1920 or 1080 compensation codes, when the compensation code is 2-bit data, the internal memory is approximately 2.5 to 4 kbit . ≪ / RTI >

That is, the display device 100 of the present invention generates compensation data (CD) and compensation code (Code) on a pixel-by-pixel basis, thereby reducing the memory capacity in comparison with generating compensation data on a subpixel- can do.

On the other hand, the compensation code generating unit 153 may generate a compensation code for each pixel in accordance with the exposure information SI provided from the outside.

5 is a flowchart illustrating a method of generating a compensation code according to another embodiment of the present invention.

Referring to FIGS. 3 and 5, the compensation code generating unit 153 can predict a location where stains such as stitches are generated according to the exposure information SI provided from the outside (S51).

For example, the display panel 110 can be divided into a plurality of exposure processes in the longitudinal direction using an exposure apparatus having a predetermined exposure width. The compensation code generating unit 153 can extract coordinates corresponding to the boundary between the exposure areas of the display panel 110 from the exposure width information SI according to the division exposure process. For example, between two adjacent pixels of the display panel 110 corresponding to the extracted exposure area coordinates or adjacent two of the plurality of subpixels of one pixel according to the extracted exposure area coordinates, It is possible to predict between the pixels the position at which the smear will occur.

Then, the compensation code generating unit 153 may generate a compensation code in units of pixels according to the predicted spot occurrence position (S53).

The compensation code can be generated as binary data of two or more bits. Further, since the exposure process proceeds in the longitudinal direction of the display panel 110, the compensation code Code can be generated for each of a plurality of pixels arranged in the same longitudinal direction of the display panel 110 in the same manner.

2 to 4, the compensation unit 155 compensates the gradation level of the image data RGB 'according to the compensation data CD and the compensation code Code, and outputs the compensated image data RGB ") (S60). The compensation unit 155 may output the compensated image data RGB '' by compensating the gradation level of the image data RGB 'at least once.

6 is a flowchart illustrating an image data compensation method of the compensation unit shown in FIG.

Referring to FIGS. 3 and 6, the compensation unit 155 can perform primary compensation of the image data RGB 'using the compensation data CD and the compensation code, and output the compensated data (S61). Here, the compensation unit 155 may compensate the gradation level of the image data RGB 'applied to the plurality of pixels P1 to P3 by the compensation data CD according to the compensation code Code.

7A and 7B, the compensation data generation unit 151 and the compensation code generation unit 153 divide the first pixel P1 into the compensation data CD of 8 and 00 and the compensation code The second pixel P2 generates the compensation data CD and the compensation code Code of 10 and 01 and the third pixel P3 generates the compensation data CD of 12 and 00, A code is generated. Here, the compensation code (Code) 00 means that there is no gradation difference between a plurality of subpixels in one pixel, and the compensation code (Code) 01 means that there is a gradation difference between R subpixels and G subpixels in one pixel it means.

Since the compensation code of the first pixel P1 is 00, the image data RGB 'provided to each of the R, G and B sub-pixels R1, G1 and B1 in the first pixel P1 is Primary compensation is performed to add the compensation data (CD) 8. Since the compensation code of the second pixel P2 is 01, the compensation data of the R, G, and B sub-pixels R2 , G2, and B2 are added to the image data RGB 'by eight. Since the compensation code of the third pixel P3 is 00, the third pixel P3 stores the image data RGB 'provided to the R, G and B sub-pixels R3, G3 and B3 Primary compensation is performed to add up compensation data (CD) 12.

8A and 8B, by the compensation data generation section 151 and the compensation code generation section 153, the first pixel P1 stores compensation data (CD) and compensation code (CD) of 8, 000 The second pixel P2 generates the compensation data CD and the compensation code Code of 10 and 010 and the third pixel P3 generates the compensation data CD of 12 and 000, A code is generated. Here, the compensation code Code 000 means that there is no difference in gradation between a plurality of subpixels in one pixel, and the compensation code 010 means that R pixels and G subpixels or G subpixels and B It means that the gradation difference exists between subpixels.

Since the compensation code of the first pixel P1 is 000, the image data RGB 'provided to each of the R, G and B sub-pixels R1, G1 and B1 in the first pixel P1 is Primary compensation is performed to add the compensation data (CD) 8. In addition, since the compensation code of the second pixel P2 is 010, in the second pixel P2, the R, G, and B sub-pixels R2 , G2, and B2 are added to the image data RGB 'by eight. In addition, since the compensation code of the third pixel P3 is 000, the third pixel P3 stores the image data RGB 'provided to each of the R, G and B sub-pixels R3, G3 and B3 Primary compensation is performed to add up compensation data (CD) 12.

That is, the compensation unit 155 generates 1 (one) of adding or subtracting the gradation level of the image data RGB 'applied to the subpixels of each pixel of the display panel 110 by the compensation data CD according to the compensation code Code It is possible to perform difference compensation. At this time, when the compensation code (Code) is generated with a difference in gradation of each subpixel in one pixel, the compensating unit 155 uses the compensating data of one pixel and the adjacent pixel, Primary compensation for adding or subtracting the gradation level of the image data RGB 'applied to the pixel can be performed.

Referring again to FIG. 6, the compensation unit 155 may perform secondary compensation of the primary compensated image data using the compensation data CD and the compensation code Code (S63).

Here, the compensation unit 155 can perform secondary compensation of the image data RGB 'applied to the plurality of sub-pixels in the corresponding pixel according to the compensation code. In other words, the compensation unit 155 applies compensation data (CD) to each subpixel of one pixel only when the compensation code (Code) is generated with a gradation difference of each subpixel in one pixel The image data (RGB ') can be subjected to secondary compensation.

7A through 7C, the compensation data generation unit 151 and the compensation code generation unit 153 generate compensation data (CD) and compensation codes (CD) of 8 and 00 by the first pixel P1, The second pixel P2 generates the compensation data CD and the compensation code Code of 10 and 01 and the third pixel P3 generates the compensation data CD of 12 and 00, A code is generated.

The compensating unit 155 firstly compensates the gradation level of the image data RGB 'applied to the R, G, and B pixels of the first pixel P1 and the sub pixels R1, G1, and B1 to +8 , The gradation level of the image data RGB 'applied to the R, G, and B sub-pixels R2, G2 and B2 of the second pixel P2 is + And the gradation level of the image data RGB 'applied to the R, G, and B sub-pixels R3, G3, and B3 is +12.

The compensation unit 155 corrects the R, G, and B signals using the compensation data CD for the pixel in which the compensation code is generated, that is, the second pixel P2, in which the gradation difference of each sub- The gradation levels of the image data RGB 'applied to the G, B sub-pixels R2, G2, and B2 can be secondarily compensated.

First, the compensation unit 155 judges from the compensation code 01 of the second pixel P2 that there is a gradation difference between the R subpixel R2 and the G subpixel G2 of the second pixel P2 can do.

The compensation unit 155 compensates the G subpixel G2 and the B subpixel G2 of the image data RGB 'applied to the R, G and B subpixels R2, G2 and B2 of the second pixel P2 B2 to compensate the gradation level of the image data RGB 'applied to the second pixel P2 by the compensation data CD of the second pixel P2.

That is, the image data RGB 'applied to the G sub-pixel G2 and the B sub-pixel B2 of the two pixels P2 can be compensated twice by the compensation unit 155. [ The gradation level of the compensated image data RGB '' applied to the G subpixel G2 and the B subpixel B2 of the second pixel P2 is compared with the gradation level of the original image data RGB ' +18 can be increased.

8A and 8C, the compensation data generation unit 151 and the compensation code generation unit 153 divide the first pixel P1 into the compensation data CD and the compensation code The second pixel P2 generates the compensation data CD and the compensation code Code of 10 and 010 and the third pixel P3 generates the compensation data CD of 12 and 000, A code is generated.

The compensating unit 155 firstly compensates the gradation level of the image data RGB 'applied to the R, G, and B pixels of the first pixel P1 and the sub pixels R1, G1, and B1 to +8 , The gradation level of the image data RGB 'applied to the R, G, and B sub-pixels R2, G2 and B2 of the second pixel P2 is + And the gradation level of the image data RGB 'applied to the R, G, and B sub-pixels R3, G3, and B3 is +12.

The compensation unit 155 corrects the R, G, and B signals using the compensation data CD for the pixel in which the compensation code is generated, that is, the second pixel P2, in which the gradation difference of each sub- The gradation levels of the image data RGB 'applied to the G, B sub-pixels R2, G2, and B2 can be secondarily compensated.

First, the compensation unit 155 compares the compensation code 010 of the second pixel P2 with the R subpixel R2, the G subpixel G2 and the G subpixel G2 of the second pixel P2, It can be determined that there is a difference in gradation between the B sub-pixels B2.

The compensation unit 155 compensates the image data RGB applied to the G subpixel G2 among the image data RGB 'applied to the R, G and B subpixels R2, G2 and B2 of the second pixel P2, (RGB) of the second pixel P2 by the compensation data (CD) 10 of the second pixel P2.

That is, the image data RGB 'applied to the G sub-pixel G2 of the two pixels P2 can be compensated twice by the compensation unit 155. [ The grayscale level of the compensated image data RGB '' applied to the G subpixel G2 of the second pixel P2 can be increased by +18 compared to the grayscale level of the original image data RGB ' .

The display device 100 according to the present invention is applied to each subpixel of the display panel 110 according to the pixel level information or the exposure width information of all the subpixels R1 to B3 of the display panel 110 The image data RGB 'is compensated at least twice and the image data RGB' is compensated more than once in the case where band-like unevenness such as a stitch is generated, It is possible to prevent defects from being generated.

Further, even if the stitch smudges are generated in one subpixel arranged on the same line in the longitudinal direction of the display panel 110, the position can be accurately determined, and reliability of image data compensation can be enhanced.

The compensation data CD and the compensation code Code are generated for each pixel of the display panel 110 and compensated for the image data RGB ' The capacity of the memory for storing can be reduced.

Although the data compensator 155 is described as being included in the timing controller 140, the data compensator 150 may be configured as a separate unit from the timing controller 140.

The image data compensating apparatus for compensating the image data in the liquid crystal display apparatus among the flat panel display apparatus has been described above. However, the present invention is not limited thereto, and the present invention can be similarly applied to all display devices, such as organic light emitting display devices, which use a divided exposure process in the manufacturing process of a display device.

While a number of embodiments have been described in detail above, it should be construed as being illustrative of preferred embodiments rather than limiting the scope of the invention. Therefore, the invention should not be construed as limited to the embodiments described, but should be determined by equivalents to the appended claims and the claims.

100: display device 110: display panel
120: Gate driver 130: Data driver
140: timing controller 150: data compensator
151: compensation data generation unit 153: compensation code generation unit
155:

Claims (11)

A compensation data generation unit for generating compensation data on a pixel basis from luminance level information for each of a plurality of subpixels of the display panel;
A compensation code generating unit for generating a compensation code for each pixel from the brightness level information; And
And a compensation unit for compensating a gradation level of image data output to the display panel according to the compensation data and the compensation code. The method according to claim 1,
Wherein the compensation data is generated as an average value of luminance level information for each of the plurality of subpixels. The method according to claim 1,
Wherein the compensation data is generated as a difference value of luminance level information for each of the plurality of subpixels. The method according to claim 1,
Wherein the compensation code is generated according to the positions of two subpixels having different brightness level information among the brightness level information for each of the plurality of subpixels. The method according to claim 1,
Wherein the compensation code is generated with at least two bits of data. The method according to claim 1,
Wherein the compensation code is generated identically for a plurality of pixels arranged in a line on the display panel. The method according to claim 1,
Wherein the compensation code is generated according to externally provided exposure width information. The method according to claim 1,
Wherein the compensation unit compensates the gradation level of the image data at least once in units of subpixels using the compensation data according to the compensation code. 9. The method of claim 8,
If the brightness level information for each of the plurality of subpixels of the first pixel is the same,
Wherein the compensation unit adds or subtracts the gradation level of the image data applied to each of the plurality of subpixels of the first pixel by the compensation data of the first pixel. 9. The method of claim 8,
If the luminance level information for each of the plurality of subpixels of the first pixel is different,
Wherein the compensating unit performs first-order compensation by adding or subtracting the gradation level of the image data applied to each of the plurality of subpixels of the one pixel by the compensation data of the second pixel adjacent to the first pixel,
The gradation level of the primary compensated image data applied to at least one of the plurality of subpixels of the first pixel is added or subtracted by the compensation data of the first pixel according to the compensation code of the first pixel to perform secondary compensation Image data compensation device. The method according to claim 1,
Wherein the brightness level information is generated in units of subpixels from a first signal provided to the display panel and a gradation difference of a second signal obtained from the display panel according to the first signal.

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