Device and method for driving a display

Abstract

A display driving device and method for driving a display. A display driving device capable of performing overdrive compensation on image data using a comparison result between pixel data of a previous subpixel and pixel data of a current subpixel in units of horizontal rows, the display driving device comprising an overdrive controller configured to generate overdrive pixel data for a current subpixel based on a comparison result between first pixel data of a previous subpixel and second pixel data of a current subpixel in units of horizontal rows of the image data and a color arrangement pattern of the previous subpixel and the current subpixel; and a data driver configured to generate a source signal for the current subpixel based on one of the second pixel data and the overdrive pixel data, to provide the source signal to the current subpixel.

Description

Technical Field

[0001] The present specification relates to a display device, and more particularly, to a device for driving a display and a method for driving a display. Background Art

[0002] As the information society develops, the demand for display devices that display images in various forms is increasing. In response to this demand, various types of display devices are being used, such as organic light emitting display (OLED) devices and conventional liquid crystal display (LCD) devices.

[0003] When a display device displays an image, the brightness of each pixel is determined by a source signal provided via a data line connected to each pixel. However, when parasitic capacitance exists in the data line or each pixel, or when the material comprising each pixel has a delay characteristic, a delay occurs until the brightness of each pixel changes in response to the source signal. When this delay occurs in a display device, the image quality may be degraded because the display device cannot display the desired color and brightness.

[0004] For example, in the case of a liquid crystal display device, as the liquid crystal state of each pixel changes according to a source signal supplied to each pixel, the brightness of the pixel changes, and the change in pixel brightness may be delayed by the slow response speed of the liquid crystal.

[0005] To address the above issues, an overdrive compensation method has been proposed to reduce delay by compensating the source signal according to changes in the image displayed on the display device. A typical overdrive compensation method compares the previous frame data with the current frame data and compensates the pixel data of the corresponding frame for each frame based on the comparison result.

[0006] Since continuous frame data is compared, general overdrive compensation methods are only applicable when the image is a video. However, even in the case of a still image consisting of a single frame, the overdrive method needs to be applied because a delay may occur before the brightness of the pixels in the frame changes. However, since general overdrive compensation methods are based on the comparison results of frame data, there is a limitation that general overdrive compensation methods cannot be applied to still images.

[0007] Furthermore, in conventional overdrive compensation methods, when a compensation value is determined for each subpixel included in each frame, using a separate lookup table for each color of each subpixel can increase manufacturing costs and size. Furthermore, if a common lookup table is used, when the color of the display panel changes, compensation values ​​cannot be selectively determined for subpixels of a specific color, resulting in inaccurate compensation. Summary of the Invention

[0008] Therefore, the present invention is directed to providing a display driving apparatus and a display driving method capable of performing overdriving compensation on image data using a comparison result between pixel data of a previous sub-pixel and pixel data of a current sub-pixel in units of a horizontal line.

[0009] Furthermore, the present invention is directed to providing a display driving device and a display driving method capable of correcting a compensation value on a lookup table according to color arrangement patterns of previous and current sub-pixels.

[0010] Furthermore, the present invention is directed to providing a display driving apparatus and a display driving method capable of applying different weights to compensation values ​​on a lookup table according to a difference between pixel data of a previous sub-pixel and pixel data of a current sub-pixel.

[0011] According to one aspect of the present invention, a display driving device is provided, comprising: an overdriving controller configured to generate overdriving pixel data of a current subpixel based on a comparison result between first pixel data of a previous subpixel and second pixel data of a current subpixel in units of horizontal rows of image data and a color arrangement pattern of the previous subpixel and the current subpixel; and a data driver configured to generate a source signal for the current subpixel based on one of the second pixel data and the overdriving pixel data to provide the source signal to the current subpixel.

[0012] According to another aspect of the present invention, a method for driving a display is provided, comprising: comparing first pixel data of a previous subpixel and second pixel data of a current subpixel in units of horizontal lines of image data to determine whether to overdrive the current subpixel. When it is determined that the current subpixel is to be overdriven, generating overdriven pixel data for the current subpixel based on a compensation value and a color arrangement pattern of the previous subpixel and the current subpixel, determining the compensation value by using a value mapped to the first pixel data and the second pixel data on a lookup table, converting one of the second pixel data and the overdriven pixel data into a source signal, and outputting the source signal to the current subpixel. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying drawings, which are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this application, illustrate embodiments of the present invention and together with the description serve to explain the principles of the present invention. In the drawings:

[0014] Figure 1 is a diagram showing a configuration of a display system to which a display driving device according to an embodiment of the present invention is applied;

[0015] Figure 2 is a block diagram schematically showing a configuration of an overdrive controller according to one embodiment of the present invention;

[0016] Figure 3 is a diagram conceptually illustrating a method in which a compensation value calculation unit compares a previous sub-pixel on a previous horizontal line with a current sub-pixel on a current horizontal line according to the present invention;

[0017] Figure 4A is a diagram illustrating an example of determining an over-driving compensation value of a current sub-pixel by a compensation value calculation unit according to the present invention;

[0018] Figure 4B is a diagram illustrating another example of determining an overdriving compensation value of a current sub-pixel by a compensation value calculation unit according to the present invention;

[0019] Figure 5 is a diagram conceptually illustrating a method in which an overdrive pixel data generator according to the present invention generates overdrive pixel data of a current subpixel in units of horizontal rows;

[0020] Figure 6 It is conceptually shown Figure 2 A diagram showing a method in which an overdrive pixel data generator sets different weights according to differences between pixel data;

[0021] Figure 7A and Figure 7B is a diagram conceptually illustrating a method in which a reference color arrangement pattern determining unit according to the present invention determines a reference color arrangement pattern; and

[0022] Figure 8 is a flowchart illustrating a method for driving a display according to one embodiment of the present invention. DETAILED DESCRIPTION

[0023] In the specification, it should be noted that the same reference numerals that have been used to represent the same elements in other drawings are used for elements wherever possible. In the following description, when functions and configurations known to those skilled in the art are not related to the basic configuration of the present invention, their detailed description will be omitted. The terms described in the specification should be understood as follows.

[0024] The advantages and features of the present invention and their implementation methods will be illustrated by the following embodiments described with reference to the accompanying drawings. However, the present invention may be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to make the present invention thorough and complete and to fully convey the scope of the present invention to those skilled in the art. Furthermore, the present invention is limited only by the scope of the claims.

[0025] The shapes, sizes, proportions, angles, and quantities disclosed in the drawings used to describe embodiments of the present invention are merely examples, and the present invention is not limited to the details shown. Like reference numerals refer to like elements throughout. In the following description, when it is determined that a detailed description of related known functions or configurations unnecessarily obscures the main points of the present invention, the detailed description will be omitted.

[0026] Where “including,” “having,” and “comprising” described in this specification are used, another part may be added unless “only” is used. Terms in the singular form may include plural forms unless mentioned otherwise.

[0027] When constructing an element, the element is interpreted as including a margin of error, even though this is not explicitly stated.

[0028] When describing a temporal relationship, for example, when a temporal order is described as "after," "subsequently," "next," and "before," discontinuous cases may be included unless "only" or "directly" is used.

[0029] It should be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element without departing from the scope of the present invention.

[0030] The term "at least one" should be understood to include any and all combinations of one or more of the associated listed items. For example, "at least one of the first, second, and third items" means all combinations of items listed from two or more of the first, second, and third items, as well as the first, second, or third item.

[0031] The features of the various embodiments of the present invention may be coupled or combined with each other in part or in whole, and may interoperate with each other in different ways and be driven technically, as will be fully understood by those skilled in the art. The embodiments of the present invention may be performed independently of each other, or may be performed together in a mutually dependent relationship.

[0032] Hereinafter, embodiments of the present specification will be described in detail with reference to the accompanying drawings.

[0033] Figure 1 is a diagram showing a configuration of a display system to which a display driving device according to one embodiment of the present invention is applied.

[0034] like Figure 1As shown, a display system 100 to which a display driving device according to an embodiment of the present invention is applied includes a display panel 110 , a display driving device 120 , a data driver 140 , and a gate driver 150 .

[0035] The display panel 110 includes a plurality of gate lines GL1 to GLn, a plurality of data lines DL1 to DLm, and pixels P, each disposed in a plurality of pixel regions. The plurality of gate lines GL1 to GLn and the plurality of data lines DL1 to DLm are arranged to intersect with each other to define a plurality of pixel regions. The plurality of gate lines GL1 to GLn may be arranged in a horizontal direction, and the plurality of data lines DL1 to DLm may be arranged in a vertical direction, but are not limited thereto.

[0036] In one embodiment, the display panel 110 may be a liquid crystal display (LCD) panel. When the display panel 110 is a liquid crystal display panel, the display panel 110 includes a thin film transistor (TFT) and a liquid crystal cell connected to the thin film transistor (TFT). The thin film transistor (TFT) is formed in a pixel region defined by a plurality of gate lines GL1 to GLn and a plurality of data lines DL1 to DLm.

[0037] The thin film transistor TFT supplies a data signal supplied through each of the data lines DL1 to DLm to the liquid crystal cell in response to a scan pulse supplied through each of the gate lines GL1 to GLn.

[0038] A liquid crystal cell consists of a common electrode and a subpixel electrode connected to a thin-film transistor (TFT). The common electrode and subpixel electrode face each other with liquid crystal between them. Therefore, a liquid crystal cell can be equivalently represented as a liquid crystal capacitor (C1c). The liquid crystal cell includes a storage capacitor (Cst) connected to the previously activated gate line to maintain the data signal stored in the liquid crystal capacitor (C1c) until the next data signal is charged.

[0039] At the same time, the pixel area of ​​the display panel 110 can be composed of red (R), green (G) and blue (B) sub-pixels. In one embodiment, the sub-pixels can be repeatedly arranged in the order of red, green and blue within a horizontal row. In this case, in two adjacent horizontal rows, two sub-pixels connected to the same data line can have different colors. To this end, the last sub-pixel among the sub-pixels in the first horizontal row is set as a dummy pixel, and the first sub-pixel among the sub-pixels in the second horizontal row adjacent to the first horizontal row is set as a dummy pixel. Therefore, two sub-pixels with different colors can be connected to the same data line in the first and second horizontal rows.

[0040] In the above embodiment, the case where the display panel 110 is a liquid crystal display panel is described, but the display panel 110 may also be an organic light emitting diode (OLED) panel in which three color sub-pixels are formed in each pixel area.

[0041] In addition, in the above embodiment, the case where the display panel 110 is composed of three-color sub-pixels is described, but in another embodiment, the display panel 110 can also be composed of red (R), green (G), blue (B) and white (W) sub-pixels.

[0042] The display driving device 120 drives the display panel 110 and includes a timing controller 122 and an overdriving controller 124 .

[0043] The timing controller 122 receives various timing signals including a vertical synchronization signal Vsync, a horizontal synchronization signal Hsync, a data enable signal DE, and a clock signal CLK from an external system (not shown) to generate a data control signal DCS for controlling the data driver 140 and a gate control signal GCS for controlling the gate driver 150.

[0044] In one embodiment, the data control signal DCS may include a source start pulse (SSP), a source sampling clock (SSC), a source output enable signal, etc., and the gating control signal GCS may include a gating start pulse (GSP), a gating shift clock (GSC), a gating output enable signal, etc.

[0045] Here, the source start pulse controls the data sampling start timing of one or more source driver integrated circuits (ICs) (not shown) constituting the data driver 140. The source sampling clock is a clock signal that controls the sampling timing of data in each source driver IC. The source output enable signal controls the output timing of the data driver 140.

[0046] The gate start pulse controls the operation start timing of one or more gate driver integrated circuits (ICs) (not shown) constituting the gate driver 150. The gate shift clock is a clock signal generally input to one or more gate driver ICs and controls the shift timing of the scan signal (gate pulse). The gate output enable signal specifies the timing information of one or more gate driver ICs.

[0047] In addition, the timing controller 122 according to the present invention transmits the image data Idata received from the external system to the overdriving controller 124. The timing controller 122 receives the pixel data Idata or the overdriven pixel data Idata′ corresponding to the image data from the overdriving controller 124, and converts the pixel data Idata or the overdriven pixel data Idata′ into data having a format that can be processed by the data driver 140 to output the converted data to the data driver 140.

[0048] The overdriving controller 124 determines whether to overdrive the current subpixel by comparing the previous subpixel with the current subpixel in units of horizontal lines of image data. When it is determined that the current subpixel is to be overdriven, the overdriving controller 124 generates overdriven pixel data of the current subpixel.

[0049] In one embodiment, according to the present invention, when generating overdrive pixel data of a current subpixel, the overdrive controller 124 may generate the overdrive pixel data of the current subpixel based on color arrangement patterns of previous subpixels and the current subpixel.

[0050] In the following, reference will be made to Figure 2 The configuration of the overdrive controller 124 according to the present invention is described in more detail.

[0051] Figure 2 FIG. 1 is a block diagram schematically showing a configuration to which an overdrive controller according to an embodiment of the present invention is applied. Figure 2 As shown, the overdriving controller 124 according to one embodiment of the present invention includes an image data receiver 210 , a line memory 220 , a compensation value calculation unit 230 , a lookup table 240 , a correction determination unit 250 and an overdriving pixel data generator 260 .

[0052] Image data receiver 210 receives image data from timing controller 122 or an external system. In one embodiment, image data receiver 210 may receive a still image as image data. Image data receiver 210 classifies the received image data into units of horizontal lines and outputs horizontal line data, which is image data for one horizontal line, to line memory 220, compensation value calculation unit 230, and correction determination unit 250.

[0053] In another embodiment, the image data receiver 210 may also receive a moving image consisting of a plurality of frames as the image data. According to this embodiment, the image data receiver 210 may receive image data or a moving image from the timing controller 122 or an external system in units of frames, and then may classify the image data or moving image of each frame to be stored in a separate frame memory (not shown), and may classify the frames in units of horizontal lines to be stored in the line memory 220.

[0054] The line memory 220 stores horizontal line data output from the image data receiver 210. In one embodiment, the line memory 220 may store one horizontal line data output from the image data receiver 210 until the next horizontal line data is input.

[0055] According to this embodiment, when the horizontal line data HLdata2 of the current horizontal line is output from the image data receiver 210 to the compensation value calculation unit 230 and the correction determination unit 250, the line memory 220 outputs the horizontal line data HLdata1 of the previous horizontal line previously stored to the compensation value calculation unit 230 and the correction determination unit 250.

[0056] The compensation value calculation unit 230 compares the horizontal line data of the current horizontal line with the horizontal line data of the previous horizontal line to determine whether to overdrive the current sub-pixel included in the current horizontal line. When it is determined that the current sub-pixel is overdriven, the compensation value calculation unit 230 determines a compensation value for overdriving the current sub-pixel.

[0057] Specifically, the compensation value calculation unit 230 compares first pixel data of a previous sub-pixel included in a previous horizontal line with second pixel data of a current sub-pixel included in a current horizontal line, and calculates a difference between the first pixel data and the second pixel data. In this case, the previous sub-pixel and the current sub-pixel refer to pixels connected to the same data line in the previous horizontal line and the current horizontal line.

[0058] For example, Figure 3 As shown, when the first horizontal line L1 is a previous horizontal line and the second horizontal line L2 is a current horizontal line, the compensation value calculation unit 230 compares the first pixel data of the previous sub-pixel G1_1 included in the previous horizontal line L1 and the second pixel data of the current sub-pixel R2_1 included in the current horizontal line L2 to calculate the difference.

[0059] When the calculated difference is less than or equal to the threshold value, the compensation value calculation unit 230 determines not to overdrive the current subpixel and thus outputs the second pixel data Idata to the timing controller 122 .

[0060] Meanwhile, when the calculated difference value is greater than the threshold value, the compensation value calculation unit 230 determines to overdrive the current sub-pixel and determines a compensation value for overdriving the current sub-pixel using the lookup table 240 .

[0061] In one embodiment, when determining to overdrive the current subpixel, the compensation value calculation unit 230 may determine the value mapped to the first pixel data of the previous subpixel and the second pixel data of the current subpixel on the lookup table 240 as the compensation value for overdriving the current subpixel.

[0062] For example, Figure 4A As shown, when the first pixel data of the previous sub-pixel is 32, the second pixel data of the current sub-pixel is 64, and the threshold is 0, the compensation value calculation unit 230 determines to overdrive the current sub-pixel because the difference between the first pixel data and the second pixel data is 32, which is greater than the threshold. In addition, the compensation value of the current sub-pixel is determined to be 73, the value at which the first pixel data value 32 and the second pixel data value 64 intersect on the lookup table 240.

[0063] Meanwhile, when the values ​​of the first pixel data and the second pixel data are not in the lookup table 240, the compensation value calculation unit 230 may determine the values ​​mapped to the first pixel data and the second pixel data using an interpolation method. That is, the compensation value calculation unit 230 may determine the compensation value of the current sub-pixel using the values ​​mapped to the pixel data adjacent to each of the first pixel data and the second pixel data on the lookup table 240.

[0064] For example, Figure 4B As shown, when the value of the first pixel data is 112 and the value of the second pixel data is 176, the first pixel data value 112 and the second pixel data value 176 are not listed in the lookup table 240. Therefore, the compensation value calculation unit 230 can use the four values ​​176, 168, 216, and 208 to determine the compensation value of the current subpixel. The value 176 is the value of the point where the value 96 adjacent to the value 112 and the value 160 adjacent to the value 176 intersect on the lookup table 240. The value 168 is the value of the point where the value 128 adjacent to the value 112 and the value 160 adjacent to the value 176 intersect on the lookup table 240. The value 216 is the value of the point where the value 96 adjacent to the value 112 and the value 192 adjacent to the value 176 intersect on the lookup table 240. The value 208 is the value of the point where the value 128 adjacent to the value 112 and the value 192 adjacent to the value 176 intersect on the lookup table 240.

[0065] In this case, the compensation value calculation unit 230 may calculate the average of the value 176 at the point where the value 96 intersects the value 160 and the value 216 at the point where the value 96 intersects the value 192 to obtain the value 196. The compensation value calculation unit 230 may calculate the average of the value 168 at the point where the value 128 intersects the value 160 and the value 208 at the point where the value 128 intersects the value 192 to obtain the value 188. The compensation value calculation unit 230 may calculate the average of the value 196 and the value 188 to obtain the value 192, and determine the value 192 as the compensation value of the current sub-pixel.

[0066] Reference again Figure 2 In the lookup table 240, the compensation value for overdriving the current subpixel is mapped to the first pixel data of the previous subpixel included in the previous horizontal line and the second pixel data of the current subpixel included in the current horizontal line. In this case, in order to reduce storage space, only the compensation values ​​corresponding to some of the first pixel data and some of the second pixel data are recorded in the lookup table 240, and the compensation values ​​of the pixel data not recorded in the lookup table 240 are determined by interpolation.

[0067] The correction determination unit 250 detects a color arrangement pattern based on the color of the previous sub-pixel and the color of the current sub-pixel, and determines whether to correct the compensation value determined for the current sub-pixel based on the detected color arrangement pattern.

[0068] In one embodiment, the correction determination unit 250 confirms whether the detected color arrangement pattern corresponds to a predetermined reference color arrangement pattern, and when the detected color arrangement pattern corresponds to the reference color arrangement pattern, determines a compensation value for correcting the current sub-pixel. In detail, the correction determination unit 250 determines the color arrangement pattern based on the colors of the previous sub-pixel and the current sub-pixel connected to the same data line in the previous horizontal line and the current horizontal line. For example, Figure 3 As shown, in the previous horizontal line L2 and the current horizontal line L3, the color arrangement pattern is determined to be RG because the color of the previous sub-pixel connected to the second data line is R and the color of the current sub-pixel is G. In this example, when the reference color arrangement pattern is RG, the correction determination unit 250 may determine the compensation value for correcting the current sub-pixel connected to the second data line, the fifth data line, and the eighth data line in the previous horizontal line L2 and the current horizontal line L3.

[0069] The overdrive pixel data generator 260 generates overdrive pixel data for the current subpixel based on the compensation value calculated by the compensation value calculation unit 230 and the determination result of the correction determination unit 250. Specifically, according to the determination result of the correction determination unit 250, when it is not necessary to correct the compensation value of the current subpixel, the overdrive pixel data generator 260 generates the compensation value calculated by the compensation value calculation unit 230 as the overdrive pixel data for the current subpixel.

[0070] At the same time, when it is necessary to correct the compensation value of the current sub-pixel according to the determination result of the correction determination unit 250, the over-driven pixel data generator 260 increases or decreases the compensation value by reflecting a predetermined weight into the compensation value calculated by the compensation value calculation unit 230 to generate the over-driven pixel data of the current sub-pixel.

[0071] In the following, reference will be made to Figure 4A and Figure 5 An example in which the overdrive pixel data generator 260 generates overdrive pixel data for a current sub-pixel will be described. In the following example, a case in which the threshold value is assumed to be 0 will be described.

[0072] like Figure 5 As shown, when the first horizontal line L1 is the previous horizontal line and the second horizontal line L2 is the current horizontal line, since the first pixel data of the previous sub-pixel P1 is 32 and the second pixel data of the current sub-pixel P2 is 160, the difference between the first pixel data and the second pixel data is greater than the threshold value. The compensation value calculation unit 230 determines to overdrive the current sub-pixel. In addition, the compensation value calculation unit 230 will Figure 4A The value 192 mapped to the value 32 of the first pixel data and the value 160 of the second pixel data in the lookup table 240 is set as the compensation value. Furthermore, since the color arrangement pattern of the previous subpixel P1 and the current subpixel P2 is GR, the color arrangement pattern differs from the reference color arrangement pattern RG, and the correction determination unit 250 determines that the compensation value of the current subpixel is not subject to correction. Therefore, the overdrive pixel data generator 260 outputs the compensation value 192 calculated by the compensation value calculation unit 230 as the overdrive pixel data for the current subpixel. Consequently, the current subpixel P2 emits light according to the source signal corresponding to the overdrive pixel data value 192.

[0073] Meanwhile, when the second horizontal line L2 is the previous horizontal line and the third horizontal line L3 is the current horizontal line, since the first pixel data of the previous subpixel P2 and the second pixel data of the current subpixel P3 are both 160, the difference between the first pixel data and the second pixel data is 0. Because the difference is less than or equal to the threshold value, the compensation value calculation unit 230 determines not to drive the current subpixel P3. Therefore, the compensation value calculation unit 230 outputs the value 160 of the second pixel data of the current subpixel P3, and the current subpixel P3 emits light according to the source signal corresponding to the second pixel data value 160.

[0074] Furthermore, when the third horizontal line L3 is the previous horizontal line and the fourth horizontal line L4 is the current horizontal line, since the first pixel data of the previous subpixel P3 is a value of 160 and the second pixel data of the current subpixel P4 is a value of 32, the difference between the first pixel data and the second pixel data is greater than or equal to the threshold value. Compensation value calculation unit 230 determines to overdrive the current subpixel. Furthermore, compensation value calculation unit 230 sets the value 0, which is mapped to the first pixel data value 160 and the second pixel data value 32 in lookup table 240, as the overdrive value as the compensation value. Furthermore, since the color arrangement pattern of the previous subpixel P3 and the current subpixel P4 is GR, the color arrangement pattern differs from the reference color arrangement pattern RG, and therefore correction determination unit 250 determines that the compensation value of the current subpixel is not subject to correction. Therefore, overdrive pixel data generator 260 outputs the compensation value 0 calculated by compensation value calculation unit 230 as the overdrive pixel data for the current subpixel. Consequently, the current subpixel P2 emits light according to the source signal corresponding to the overdrive pixel data value 0.

[0075] Furthermore, when the fourth horizontal line L4 is the previous horizontal line and the fifth horizontal line L5 is the current horizontal line, since the first pixel data of the previous subpixel P4 is a value of 32 and the second pixel data of the current subpixel P5 is a value of 160, the difference between the first pixel data and the second pixel data is greater than or equal to the threshold value. The compensation value calculation unit 230 determines to overdrive the current subpixel. Furthermore, the compensation value calculation unit 230 sets the value 192, which is mapped to the first pixel data value 32 and the second pixel data value 160 in the lookup table 240, as the compensation value. Furthermore, since the color arrangement pattern of the previous subpixel P4 and the current subpixel P5 is RG, and the color arrangement pattern is the same as the reference color arrangement pattern RG, the correction determination unit 250 determines that the compensation value of the current subpixel is the subject of correction. Therefore, the overdrive pixel data generator 260 outputs a value of 200 as the overdrive pixel data for the current subpixel P5, with a predetermined weight applied to the compensation value 192 calculated by the compensation value calculation unit 230. Consequently, the current subpixel P5 emits light according to the source signal corresponding to the overdrive pixel data value 200.

[0076] In one embodiment, the overdrive pixel data generator 260 may change the weight of the compensation value to be applied to the current sub-pixel according to the difference between the first pixel data and the second pixel data. Figure 6 As shown, the compensation value of the current sub-pixel D1, in which the first pixel data and the second pixel data have a difference of 32 on the lookup table 240, can be modified by reflecting the first weight. The compensation value of the current sub-pixel D2, in which the first pixel data and the second pixel data have a difference of 64 on the lookup table 240, can be modified by reflecting the second weight. The compensation value of the current sub-pixel D3, in which the first pixel data and the second pixel data have a difference of 96 on the lookup table 240, can be modified by reflecting the third weight.

[0077] According to the present invention, since the weight reflected in the compensation value according to the difference between the first pixel data and the second pixel data is variable, the correction degree of the compensation value can be changed according to the difference between the first pixel data and the second pixel data, and the over-drive compensation accuracy of the current sub-pixel can be improved.

[0078] As described above, according to the present invention, the overdrive controller 124 can determine whether to overdrive the current subpixel based on the pixel data of the previous subpixel and the current subpixel in units of horizontal lines, and when overdriving the current subpixel, the compensation value of the current subpixel is corrected based on the color arrangement pattern of the previous subpixel and the current subpixel to generate the final overdrive pixel data. Therefore, in the present invention, even when overdriving is performed using a common lookup table, the characteristics of each color can be reflected, and even when the color of the display panel 110 changes, since only the compensation value of the pixel of the corresponding color can be selectively corrected, the accuracy of overdrive compensation can be improved.

[0079] In the above embodiment, although the case where the timing controller 122 and the overdriving controller 124 are separately configured is described, this is merely an example, and the overdriving controller 124 may be included in the timing controller 122. As another example, the overdriving controller 124 may be provided between an external system and the timing controller 122. In this case, the overdriving controller 124 may directly receive image data from the external system, then generate overdriving pixel data from the image data, and transmit the overdriving pixel data to the timing controller 122. In another example, the overdriving controller 124 may be provided between the timing controller 122 and the data driver 140 to transmit the overdriving pixel data directly to the data driver 140 without passing through the timing controller 122.

[0080] At the same time, if Figure 1As shown, the display system 100 according to the present invention may further include a reference color arrangement pattern determination unit 126 that determines a reference color arrangement pattern for correcting the compensation value. Reference color arrangement pattern determination unit 126 obtains measurement values ​​by inputting a test image to the display panel 110 including a previous subpixel and a current subpixel. When there are measurement values ​​obtained at predetermined color coordinates that are spaced apart from the reference value, reference color arrangement pattern determination unit 126 may generate a reference color arrangement pattern based on the color arrangement corresponding to the area on the color coordinates where the measurement value spaced apart from the reference value is located.

[0081] For example, Figure 7A As shown, on the color coordinates, when the reference value 710 is located in the area between the first coordinate value 720 of the first color and the second coordinate value 730 of the second color and the measurement value 740 spaced apart from the reference value 710 is located in the area between the reference value 710 and the second coordinate value 730, the reference color arrangement pattern determination unit 126 may determine the color arrangement in which the first color is changed to the second color as the reference color arrangement pattern.

[0082] According to this example, when the color of the previous sub-pixel is the first color and the color of the current sub-pixel is the second color, the above-mentioned correction determination unit 250 can determine that the color arrangement pattern corresponds to the reference color arrangement pattern, and the over-drive pixel data generator 260 can determine the weight so that the over-drive pixel data becomes smaller than the second pixel data.

[0083] At the same time, if Figure 7B As shown, on the color coordinates, when the reference value 710 is located in the area between the first coordinate value 720 of the first color and the second coordinate value 730 of the second color, and the measured value 740 spaced apart from the reference value 710 is located in the area between the reference value 710 and the second coordinate value 730, the spaced apart measured value 740 changes to a curved shape. The reference color arrangement pattern determination unit 126 can transmit the characteristics of the display panel 110 to the overdrive pixel data generator 260 through the timing controller 122. Therefore, as described above, the overdrive pixel data generator 260 can change the weight according to the difference between the first pixel data and the second pixel data.

[0084] Reference again Figure 1, the data driver 140 converts the adjusted pixel data Idata or the adjusted overdrive pixel data Idata' output from the timing controller 122 into a source signal, which is an analog signal according to the data control signal DCS supplied from the timing controller 122, and then supplies the source signal to the data lines DL1 to DLm to which the corresponding sub-pixels are connected. In this case, the data driver 140 supplies the source signal of one horizontal line to the data lines DL1 to DLm every other horizontal period, wherein the scan pulse is supplied to the gate lines GL1 to GLn.

[0085] Specifically, the data driver 140 selects a gamma voltage having a predetermined level according to the grayscale value of the pixel data or the over-driven pixel data, and supplies the selected gamma voltage to the data lines DL1 to DLm.

[0086] As shown in the figure, the data driver 140 can be provided on one side, such as the upper side of the display panel 110, but in some cases, it can also be provided on one side and the other side facing each other, such as the upper side and the lower side of the display panel 110. The data driver 140 may include a plurality of source driver ICs. The data driver 140 may be formed in the shape of a tape carrier package in which the source driver ICs are mounted, but is not limited thereto.

[0087] In one embodiment, the source driver IC may include a shift register, a latch, a digital-to-analog converter (DAC), and an output buffer. In addition, the source driver IC may further include a level shifter for shifting the voltage level of the pixel data output from the timing controller 122 or the overdriven pixel data to a desired voltage level.

[0088] The gate driver 150 includes a shift register that sequentially generates scan pulses (ie, gate high pulses) in response to a gate start pulse (GSP) and a gate shift clock (GSC) in a gate control signal GCS from the timing controller 122. In response to the scan pulses, the thin film transistor TFT is turned on.

[0089] As shown in the figure, the gate driver 150 can be provided on one side, such as the left side of the display panel 110, but in some cases, it can also be provided on one side and the other side facing each other, such as the left and right sides of the display panel 110. The gate driver 150 can include a plurality of gate driver ICs. The gate driver 150 can be formed in the shape of a tape carrier package in which the gate driver IC is mounted, but is not limited thereto, and the gate driver IC can be directly mounted on the display panel 110.

[0090] In the following, reference will be made to Figure 8 A method for driving a display according to the present invention is described.

[0091] Figure 8 is a flowchart illustrating a method for driving a display according to one embodiment of the present invention. Figure 8 The method for driving a display shown can be performed by Figure 1 The display system shown is executed.

[0092] First, the display driver receives image data from an external system (S800). In one embodiment, the display driver may receive a still image as the image data. The display driver may classify the received image data in units of horizontal lines and store the horizontal line data, which is image data of one horizontal line, in a line memory.

[0093] Thereafter, the display driving apparatus determines whether to overdrive the current sub-pixel by comparing first pixel data of a previous sub-pixel and second pixel data of a current sub-pixel in units of horizontal lines of image data ( S810 ).

[0094] Specifically, the display driving device compares first pixel data of a previous sub-pixel included in a previous horizontal line with second pixel data of a current sub-pixel included in a current horizontal line, and calculates a difference between the first pixel data and the second pixel data. In this case, the previous sub-pixel and the current sub-pixel refer to pixels connected to the same data line in the previous horizontal line and the current horizontal line.

[0095] When the difference between the first pixel data and the second pixel data is greater than a threshold, the display driving device determines to overdrive the current subpixel, and when the difference between the first pixel data and the second pixel data is less than or equal to the threshold, the display driving device determines not to overdrive the current subpixel.

[0096] When it is determined not to overdrive the current sub-pixel in S810, the display driving apparatus outputs the second pixel data as the pixel data of the current sub-pixel to the data driver (S820).

[0097] Meanwhile, when it is determined in S810 that the current sub-pixel is to be overdriven, the display driving apparatus calculates a compensation value for overdriving the current sub-pixel (S830). In one embodiment, the display driving apparatus may determine a value mapped to the first pixel data of the previous sub-pixel and the second pixel data of the current sub-pixel in the lookup table as the compensation value for overdriving the current sub-pixel.

[0098] In the above embodiment, when the lookup table does not contain the values ​​of the first pixel data and the second pixel data, the display driver may determine the value mapped to the value of the first pixel data and the value of the second pixel data using interpolation. In other words, the display driver may determine the compensation value of the current sub-pixel using the value mapped to each of the values ​​of the first pixel data and the second pixel data on the lookup table.

[0099] Thereafter, the display driving apparatus determines whether to correct the compensation value calculated in S830 based on the color arrangement patterns of the previous sub-pixel and the current sub-pixel ( S840 ).

[0100] In one embodiment, when the color arrangement pattern of the previous sub-pixel and the current sub-pixel corresponds to the predetermined reference color arrangement pattern, the display driving apparatus determines to correct the compensation value determined in S830. On the other hand, when the color arrangement pattern of the previous sub-pixel and the current sub-pixel does not correspond to the predetermined reference color arrangement pattern, the display driving apparatus determines not to correct the compensation value determined in S830.

[0101] When the revised compensation value is determined in S840 , the display driving apparatus revises the compensation value by reflecting a predetermined weight in the compensation value determined in S830 ( S850 ).

[0102] In one embodiment, the display driver device may change the weight of the compensation value applied to the current sub-pixel based on the difference between the first pixel data and the second pixel data. Therefore, since the weight reflected in the compensation value based on the difference between the first pixel data and the second pixel data varies, the degree of correction of the compensation value may be changed based on the difference between the first pixel data and the second pixel data, thereby improving the overdrive compensation accuracy of the current sub-pixel.

[0103] Meanwhile, when it is determined not to correct the compensation value in S840 or to correct the compensation value in S850, the display driving apparatus generates the compensation value determined in S830 or the compensation value corrected in S850 as overdriven pixel data to output the overdriven pixel data to the data driver (S860).

[0104] Thereafter, the data driver converts the second pixel data or the over-driven pixel data into source signals and provides the source signals to corresponding pixels, thereby displaying the image data on the display panel ( S870 ).

[0105] At the same time, despite Figure 8 Although not shown in the figure, the display system according to the present invention may further include an operation of determining a reference color arrangement pattern. Specifically, the display system obtains measurement values ​​by inputting a test image to the display panel including a previous subpixel and a current subpixel. Thereafter, when a measurement value at a predetermined color coordinate is spaced apart from a reference value, the display system may generate a reference color arrangement pattern based on the color arrangement corresponding to the area at the color coordinate where the measurement value spaced apart from the reference value is arranged.

[0106] For example, Figure 7A or Figure 7BAs shown, when the reference value 710 is located in the area between the first coordinate value 720 of the first color and the second coordinate value 730 of the second color and the measurement value 740 spaced apart from the reference value is located in the area between the reference value 710 and the second coordinate value 730 on the color coordinates, the display system can determine a color arrangement in which the first color becomes the second color as a reference color arrangement pattern.

[0107] According to the present invention, since overdrive compensation can be performed on image data in units of horizontal lines, there is an effect that overdrive compensation can be performed not only on moving images but also on still images.

[0108] In addition, according to the present invention, since the compensation value recorded in the lookup table can be corrected according to the color arrangement pattern of the previous sub-pixel and the current sub-pixel, overdrive compensation can be performed using only one lookup table, thereby having the effect of reducing the manufacturing cost and size of the display device, and at the same time, even when a specific color change occurs in the display panel, color distortion can be prevented from occurring by correcting the compensation value of the corresponding color.

[0109] Furthermore, according to the present invention, even in the same color arrangement pattern, compensation accuracy can be improved by setting different weights to be applied to compensation values ​​recorded in a lookup table according to the difference between pixel data of a previous subpixel and pixel data of a current subpixel.

[0110] It should be understood by those skilled in the art that the present invention may be implemented in other specific forms without changing the technical concept and essential features of the present invention.

[0111] All disclosed methods and processes described herein may be implemented, at least in part, using one or more computer programs or components. These components may be provided as a series of computer instructions via any conventional computer-readable medium or machine-readable medium, including volatile and non-volatile memory, such as random access memory (RAM), read-only memory (ROM), flash memory, magnetic or optical disk, optical storage or other storage medium. The instructions may be provided as software or firmware and may be implemented in whole or in part with a hardware configuration (e.g., an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a digital signal processor (DSP) or any other similar device). These instructions may be configured to be executed by one or more processors or other hardware configurations, and these processors or other hardware configurations are allowed to execute all or part of the methods and processes disclosed herein when executing the series of computer instructions.

[0112] Therefore, the above embodiments should be understood to be illustrative rather than restrictive in every aspect. The scope of the present invention will be defined by the appended claims rather than the detailed description above, and all changes and modifications derived from the meaning and scope of the claims and their equivalents should be understood to be included within the scope of the present invention.

[0113] Cross-references to related applications

[0114] This application claims the benefit of Korean Patent Application No. 10-2020-0040389, filed on April 2, 2020, which is hereby incorporated by reference as if fully set forth herein.

Claims

1. A display driving device, comprising: an overdriving controller configured to generate overdriving pixel data of the current subpixel based on a comparison result between first pixel data of a previous subpixel and second pixel data of a current subpixel in units of horizontal lines of image data and a color arrangement pattern of the previous subpixel and the current subpixel; as well as a data driver configured to generate a source signal of the current sub-pixel based on one of the second pixel data and the overdrive pixel data to provide the source signal to the current sub-pixel, Herein, the current sub-pixel is a sub-pixel included in a first horizontal row which is a current horizontal row, the previous sub-pixel is a sub-pixel included in a second horizontal row immediately before the current horizontal row, and the previous sub-pixel and the current sub-pixel are connected to the same data line.

2. The display driving device according to claim 1, wherein: The overdrive controller comprises: a compensation value calculation unit configured to calculate a difference between the first pixel data and the second pixel data, and when the difference is greater than a threshold, determine a compensation value using values ​​of the first pixel data and the second pixel data mapped to a lookup table; a correction determination unit configured to detect a color arrangement pattern based on the color of the previous sub-pixel and the color of the current sub-pixel, and determine whether to correct the compensation value based on a comparison result between the detected color arrangement pattern and a reference color arrangement pattern; and An overdrive pixel data generator is configured to generate overdrive pixel data by reflecting a predetermined weight in the compensation value when determining to correct the compensation value.

3. The display driving device according to claim 2, wherein: When the difference is less than or equal to the threshold, the compensation value calculation unit outputs the second pixel data as the overdrive pixel data, and When the correction determination unit determines not to correct the compensation value, the overdrive pixel data generator outputs the compensation value determined by the compensation value calculation unit as the overdrive pixel data.

4. The display driving device according to claim 2, wherein: The overdrive pixel data generator changes a weight according to the difference.

5. The display driving device according to claim 2, further comprising a reference color arrangement pattern determining unit, the reference color arrangement pattern determining unit being configured to determine the reference color arrangement pattern based on the color arrangement of an area on the color coordinate corresponding to the measurement value spaced apart from the reference value, when there is a measurement value spaced apart from a reference value on the color coordinate among the values ​​measured when a test image is input to a display panel including the previous sub-pixel and the current sub-pixel.

6. The display driving device according to claim 5, wherein: When the reference value is located in a region between a first coordinate value of a first color and a second coordinate value of a second color on the color coordinates, and a measured value spaced apart from the reference value is located in a region between the reference value and the second coordinate value, the reference color arrangement pattern determination unit determines a color arrangement in which the first color is changed to the second color as the reference color arrangement pattern.

7. The display driving device according to claim 6, wherein: When the color of the previous sub-pixel is the first color and the color of the current sub-pixel is the second color, the correction determination unit determines that the color arrangement pattern corresponds to the reference color arrangement pattern, and The overdrive pixel data generator determines a weight such that the overdrive pixel data is smaller than the second pixel data.

8. The display driving device according to claim 2, wherein: When the first pixel data and the second pixel data do not exist in the lookup table, the compensation value calculation unit uses four values ​​respectively mapped to the third pixel data and the fourth pixel data adjacent to the first pixel data and the fifth pixel data and the sixth pixel data adjacent to the second pixel data to calculate the compensation value for overdriving the current sub-pixel.

9. The display driving device according to claim 2, wherein: The overdrive controller further includes a line memory in which the image data is stored in units of horizontal lines.

10. The display driving device according to claim 9, wherein: When horizontal line data of a current horizontal line including the current sub-pixel is input from the outside and output to the compensation value calculation unit and the correction determination unit, the line memory outputs previously stored horizontal line data of a horizontal line including the previous sub-pixel to the compensation value calculation unit and the correction determination unit.

11. A method for driving a display, the method comprising the following steps: comparing first pixel data of a previous sub-pixel and second pixel data of a current sub-pixel in units of horizontal lines of image data to determine whether to overdrive the current sub-pixel; When it is determined to overdrive the current sub-pixel, generating overdriven pixel data of the current sub-pixel based on the compensation value and the color arrangement pattern of the previous sub-pixel and the current sub-pixel, and determining the compensation value by using a value on a lookup table mapped to the first pixel data and the second pixel data; as well as converting one of the second pixel data and the over-driven pixel data into a source signal, and outputting the source signal to the current sub-pixel, Herein, the current sub-pixel is a sub-pixel included in a first horizontal row which is a current horizontal row, the previous sub-pixel is a sub-pixel included in a second horizontal row immediately before the current horizontal row, and the previous sub-pixel and the current sub-pixel are connected to the same data line.

12. The method according to claim 11, further comprising the steps of: comparing the color arrangement pattern with a reference color arrangement pattern to determine whether to correct the compensation value, wherein, when determining to modify the compensation value, the overdrive pixel data is generated by reflecting a predetermined weight in the compensation value, and When it is determined not to correct the compensation value, the compensation value is determined as the over-drive pixel data.

13. The method according to claim 12, wherein: The weight is changed according to a difference between the first pixel data and the second pixel data.

14. The method according to claim 12, further comprising the steps of: determining the reference color arrangement pattern based on values ​​measured when a test image is input to a display panel including the previous sub-pixel and the current sub-pixel, and When there are measurement values ​​spaced apart from reference values ​​on color coordinates among the measurement values, the reference color arrangement pattern is determined based on a color arrangement of an area on the color coordinates corresponding to the measurement values ​​spaced apart from the reference values.

15. The method according to claim 14, wherein When the reference value is located in a region between a first coordinate value of a first color and a second coordinate value of a second color on the color coordinates, and the measured value spaced apart from the reference value is located in a region between the reference value and the second coordinate value, a color arrangement that changes the first color to the second color is determined as the reference color arrangement pattern.

16. The method according to claim 15, wherein If the color of the previous sub-pixel is the first color and the color of the current sub-pixel is the second color, determining that the color arrangement pattern corresponds to the reference color arrangement pattern, thereby determining that the compensation value is to be corrected, and The over-driven pixel data is generated to be smaller than the second pixel data.

17. The method according to claim 11, wherein When the first pixel data and the second pixel data do not exist on the lookup table, the compensation value for overdriving the current sub-pixel is calculated by using four values ​​respectively mapped to the third pixel data and the fourth pixel data adjacent to the first pixel data and the fifth pixel data and the sixth pixel data adjacent to the second pixel data.

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