Data processing device for compensating data

Abstract

This invention relates to a data processing apparatus for compensating data. Embodiments can improve the solid color brightness ratio by compensating the image data of the current pixel based on the result of comparing the image data of the current pixel with the image data of previous pixels.

Description

Technical Field

[0001] This invention relates to a technique for compensating image data. Background Technology

[0002] Recent advancements in information technology have further emphasized the importance of displays as the medium for transmitting visual information. To maintain a prominent position in the future, displays must meet requirements such as low power consumption, thin panels, portability, and high resolution.

[0003] In display devices, liquid crystal display (LCD) devices that use liquid crystals are devices that utilize the optical anisotropy of liquid crystals, and have been developed to replace cathode ray tubes (CRTs) due to their advantages such as thin panels, small size, low power consumption and high definition.

[0004] Since liquid crystals themselves cannot emit light, liquid crystal display devices can have a backlight unit (BLU) for supplying light. The light emission of a liquid crystal is related to its response speed—how quickly it can transmit light. Therefore, various measures have been proposed to improve the response speed of liquid crystals.

[0005] Typical methods can be used to compensate image data and increase or decrease the data voltage of the image data to correspond to the compensated image data. Therefore, the liquid crystal display device can compare the current image data with previous image data, and if the value of the current image data is greater than the value of the previous image data, a higher voltage than the current image data can be applied; conversely, if the value of the current image data is less than the value of the previous image data, a lower voltage than the current image data can be applied. Here, the liquid crystal display device can compare the image data based on lines (comparing the image data of the current line with the image data of the previous line) or frames (comparing the image data of the current frame with the image data of the previous frame).

[0006] However, there may be limitations if image data is compared based on lines or frames. For example, liquid crystal displays with dual gates have multiple lines arranged in a way that makes it difficult to compensate for image data by comparing lines. Therefore, the time for applying the data voltage (i.e., the charging time) may be insufficient. Furthermore, since conventional methods focus on improving the liquid crystal's response speed, it may not be easy to improve both the response speed and the pure color brightness ratio. Moreover, even if conventional methods improve the pure color brightness ratio, the improvement may be insignificant because the degree of improvement varies depending on the grayscale value.

[0007] In this regard, this embodiment will provide an image data compensation technique for improving brightness by improving the response speed of the liquid crystal and increasing the pure color brightness ratio. Summary of the Invention

[0008] In view of this background, the purpose of this embodiment is to provide an image data compensation technique that performs a first compensation for improving the response speed of the liquid crystal and a second compensation for increasing the brightness ratio of pure colors.

[0009] Another objective of this embodiment is to provide an image data compensation technique by taking into account the difference between the image data of the current pixel and the image data of the previous pixel, as well as the value of the image data of the current pixel, for a second compensation used to increase the solid color brightness ratio.

[0010] To achieve the above objectives, an embodiment provides a data processing apparatus for generating image data of a first sub-pixel and a second sub-pixel of different colors connected to a data line. The data processing apparatus includes: a first data compensation circuit configured to generate compensated image data, the compensated image data being used to apply overdriving or underdriving to the grayscale values ​​of the image data of the first sub-pixel and the second sub-pixel driven sequentially after the first sub-pixel; and a second data compensation circuit configured to reduce the grayscale value of the compensated image data of the second sub-pixel when the grayscale value of the compensated image data of the first sub-pixel is the same as or different within a predetermined range from the grayscale value of the compensated image data of the second sub-pixel.

[0011] In this device, the second data compensation circuit can reduce the gray value of the compensation image data of the second sub-pixel by reflecting the difference between the gray value of the compensation image data of the first sub-pixel and the gray value of the compensation image data of the second sub-pixel.

[0012] In this device, the second data compensation circuit can reduce the gray value of the compensation image data of the second sub-pixel by a larger amount as the difference between the gray value of the compensation image data of the first sub-pixel and the gray value of the compensation image data of the second sub-pixel decreases.

[0013] In this device, the second data compensation circuit can reduce the gray value of the compensation image data of the second sub-pixel by a smaller amount as the difference between the gray value of the compensation image data of the first sub-pixel and the gray value of the compensation image data of the second sub-pixel increases.

[0014] In this device, the second data compensation circuit can determine the amount of reduction in the grayscale value of the compensation image data of the second sub-pixel by reflecting the grayscale value of the compensation image data of the second sub-pixel.

[0015] In this device, the second data compensation circuit can reduce the gray value of the compensation image data of the second sub-pixel by a larger amount as the gray value of the compensation image data of the second sub-pixel increases.

[0016] In this device, the second data compensation circuit can reduce the gray value of the compensation image data of the second sub-pixel by a smaller amount as the gray value of the compensation image data of the second sub-pixel decreases.

[0017] In this device, the second data compensation circuit can use a lookup table to determine the amount of reduction in the grayscale value of the compensated image data of the second sub-pixel.

[0018] In this device, the first sub-pixel and the second sub-pixel can be arranged in the same row on the display panel and can be connected to different gate lines.

[0019] Another embodiment provides a data processing apparatus for generating image data of a first sub-pixel and a second sub-pixel of different colors connected to a data line. The data processing apparatus includes: a comparison circuit configured to compare the image data of the first sub-pixel with the image data of a second sub-pixel driven sequentially after the first sub-pixel; and a data compensation circuit configured to reduce the gray value of the image data of the second sub-pixel when the gray value of the image data of the first sub-pixel is the same as or different within a predetermined range from the gray value of the image data of the second sub-pixel, thereby generating compensated image data of the second sub-pixel.

[0020] In this device, the data compensation circuit can adjust the amount by which the gray value of the second sub-pixel's image data is reduced, based on the difference between the gray value of the first sub-pixel's image data and the gray value of the second sub-pixel's image data.

[0021] In this device, the data compensation circuit can adjust the amount by which the grayscale value of the image data of the second sub-pixel is reduced, based on the grayscale value of the image data of the second sub-pixel.

[0022] In this device, the data line can span multiple gate lines, and the first sub-pixel and the second sub-pixel can be connected to the data line and to corresponding gate lines among the multiple gate lines.

[0023] In this device, the pure color luminance ratio of a frame including the grayscale value of the compensated image data of the second sub-pixel is higher than the pure color luminance ratio of a frame including the grayscale value of the image data of the second sub-pixel, and wherein the pure color luminance ratio can be defined as the ratio of the sum of the luminance values ​​of red, green and blue to the luminance value of white.

[0024] In this device, the first sub-pixel and the second sub-pixel can be arranged in the same row on the display panel and can be connected to different gate lines.

[0025] As described above, according to this embodiment, the response speed and image quality of the liquid crystal can be improved by compensating for the data voltage on a pixel-by-pixel basis (overdrive or underdrive).

[0026] Furthermore, according to this embodiment, the pure color luminance ratio can be improved by further reducing the luminance of white, wherein the pure color luminance ratio is defined as the ratio of the sum of the luminance values ​​of red, green and blue to the luminance of white. Attached Figure Description

[0027] Figure 1 This is a diagram illustrating the structure of a display device according to an embodiment.

[0028] Figure 2 This is a diagram showing the connections between the subpixels included in the panel.

[0029] Figure 3 This is a diagram illustrating the connections of sub-pixels included in a panel according to an embodiment.

[0030] Figure 4 This is a diagram illustrating the structure of a data processing apparatus according to an embodiment.

[0031] Figure 5 This is a diagram illustrating an example of a lookup table, according to an embodiment, for adjusting the amount of reduction in the grayscale value of a current sub-pixel by reflecting the grayscale value of the current sub-pixel.

[0032] Figure 6 This is a flowchart illustrating the operation of a data processing apparatus according to an embodiment.

[0033] Figure 7 This is a diagram illustrating the structure of a data processing apparatus according to another embodiment.

[0034] Figure 8 This is a graph illustrating the change in data voltage between a previous sub-pixel and a current sub-pixel without first compensation, according to another embodiment.

[0035] Figure 9 This is a diagram illustrating the change in data voltage between the previous sub-pixel and the current sub-pixel under the condition of first compensation according to another embodiment.

[0036] Figure 10 This is a diagram illustrating an example of a lookup table for generating compensated image data according to another embodiment.

[0037] Figure 11 This is a flowchart illustrating the operation of a data processing apparatus according to another embodiment. Detailed Implementation

[0038] Figure 1This is a diagram illustrating the structure of a display device according to an embodiment.

[0039] refer to Figure 1 The display device 100 may include a panel 110, a data driving device 120, a gate driving device 130, and a data processing device 140, etc.

[0040] Multiple data lines DL and multiple gate lines GL can be arranged on panel 110, and multiple pixels can be arranged on panel 110. A pixel may include multiple sub-pixels SP. Here, a sub-pixel may be R (red), G (green), B (blue), or W (white), etc. A pixel may be configured as an RGB sub-pixel SP, an RGBG sub-pixel SP, or an RGBW sub-pixel SP. In the following description, for ease of description, it will be described under the assumption that a pixel includes RGB sub-pixels.

[0041] The data driving device 120, the gate driving device 130, and the data processing device 140 are devices for generating signals for displaying images on the panel 110.

[0042] The gate driving device 130 can supply a gate driving signal with an on or off voltage to the gate line GL. If the gate driving signal with an on voltage is supplied to the sub-pixel SP, the sub-pixel SP is connected to the data line DL. Conversely, if the gate driving signal with an off voltage is supplied to the sub-pixel SP, the connection between the sub-pixel SP and the data line DL is disconnected. The gate driving device 130 may be referred to as a "gate driver".

[0043] The data driving device 120 can supply a data voltage Vdata to the sub-pixel SP via the data line DL. The data voltage Vdata supplied to the data line DL can be supplied to the sub-pixel SP according to the gate driving signal. The data driving device 120 can be referred to as a "source driver".

[0044] The data driving device 120 can generate multiple gamma voltages and output a data voltage Vdata corresponding to the image data RGB from among the multiple gamma voltages. The data driving device 120 may include a digital-to-analog converter (DAC) and a buffer. The DAC can select one of the multiple gamma voltages in response to the image data RGB and output the selected voltage to the buffer. The buffer can amplify the selected voltage and apply the data voltage Vdata to the sub-pixel SP via the data line DL.

[0045] The data drive device 120 may include at least one integrated circuit, which may be connected to the bonding pads of the panel 110 via tape auto-bonding (TAB) or glass flip-chip (COG) bonding, or may be formed directly on the panel 110, or may be formed by integration onto the panel 110 according to embodiments. Alternatively, the data drive device 120 may be implemented as a thin-film flip-chip (COF) type.

[0046] The data processing unit 140 can supply control signals to the gate driving unit 130 and the data driving unit 120. For example, the data processing unit 140 can send a gate control signal GCS for starting scanning to the gate driving unit 130. Additionally, the data processing unit 140 can output image data RGB to the data driving unit 120. Furthermore, the data processing unit 140 can send a data control signal DCS for controlling the data driving unit 120 to supply data voltage Vdata to each sub-pixel SP. The data processing unit 140 can be referred to as a "timing controller".

[0047] Figure 2 This is a diagram showing the connections between the sub-pixels included in the panel.

[0048] refer to Figure 2 This illustrates an example of general subpixel connections. Subpixels with only the same color can be connected to a single data line. For example, if a pixel comprises multiple RGB subpixels, the individual subpixels are arranged along a gate line in RGB order and connected to that gate line. Thus, respectively, the R subpixel can be connected to the first data line DL1, the G subpixel can be connected to the second data line DL2, and the B subpixel can be connected to the third data line DL3. RGB subpixels can be sequentially connected to the fourth data lines DL4 through the sixth data lines DL6 in the same manner.

[0049] When a sub-pixel is scanned by a gate line, a data voltage can be received through a data line. For example, if any one of the first gate lines GL1 to the sixth gate line GL6 is driven, and if a data voltage is applied through the first data line DL1, the data voltage can be applied to the R sub-pixel.

[0050] Figure 3 This is a diagram illustrating the connections of sub-pixels included in a panel according to an embodiment.

[0051] refer to Figure 3The diagram illustrates an example of subpixel connections according to an embodiment. Multiple subpixels of different colors can be connected to a single data line. For example, in the case where a pixel comprises multiple RGB subpixels, two subpixels of different colors can be connected to a single data line, and these two subpixels can be connected to different gate lines. Therefore, both the R subpixel and the G subpixel can be connected to the first data line DL1, and the R subpixel and the G subpixel can be connected to gate line GL11 (first-first) and gate line GL12 (first-second), respectively. Additionally, both the G subpixel and the B subpixel can be connected to the first data line DL1, and the G subpixel and the B subpixel can be connected to gate line GL21 (second-first) and gate line GL22 (second-second), respectively.

[0052] This arrangement is sometimes referred to as a "dual-gate structure". In a dual-gate structure, two sub-pixels connected to a data line can form the same row in the panel, but can be connected to different gate lines.

[0053] Multiple subpixels can be arranged alternately along multiple gate lines. For example, subpixels can be arranged in RGB order between gate line 1-1 GL11 and gate line 1-2 GL12 based on a first data line DL1. On the other hand, subpixels can be arranged in GBR order, different from the RGB order, between gate line 2-1 GL21 and gate line 2-2 GL22.

[0054] If multiple sub-pixels are scanned via a single gate line, data voltage can be received via a single data line. However, since the number of data lines is reduced and the number of gate lines is increased in the pixel connection example according to the embodiment, unlike the typical pixel connection example, data voltage can be applied more frequently via a single data line. For example, if in Figure 2 By driving a gate line, a data voltage can be applied to all six sub-pixels (RGBRGB) connected to that gate line at once. On the other hand, in... Figure 3 In this process, if gate line GL11 (1-1) is driven, a data voltage is applied to the three sub-pixels RBG connected to gate line GL11. Then, if gate line GL12 (1-2) is driven, a data voltage is applied to the three sub-pixels GRB connected to gate line GL12 (1-2). To drive all six sub-pixels RGBRGB, a data voltage can be applied twice to the first data line DL1 through the third data line DL3.

[0055] Figure 4 This is a diagram illustrating the structure of a data processing apparatus according to an embodiment.

[0056] refer to Figure 4According to the embodiment, the data processing apparatus 140 may include a comparison circuit 410 and a data compensation circuit 420, and the data driving apparatus 120 may include a data voltage output circuit 121. Additionally, the data compensation circuit 420 may include a compensation value calculation circuit 421 and a compensation data generation circuit 422.

[0057] The data processing device 140 can generate image data of multiple sub-pixels with different colors connected to a data line. To this end, the data processing device 140 can compare the image data of a first sub-pixel with the image data of a second sub-pixel driven after the first sub-pixel. If the image data of the first sub-pixel and the image data of the second sub-pixel are the same or different within a predetermined range, the grayscale value of the image data of the second sub-pixel can be reduced, thereby generating compensated image data. Outputting the compensated image data can increase the solid color brightness ratio of the image.

[0058] The pure color luminance ratio can be defined as the ratio of the sum of the luminance values ​​of red, green, and blue to the luminance of white. That is, the pure color luminance ratio can be "(R luminance + G luminance + B luminance) / W luminance". R luminance indicates the luminance of red, G luminance indicates the luminance of green, B luminance indicates the luminance of blue, and W luminance indicates the luminance of white. The data processing device 140 can increase the total pure color luminance ratio by reducing W luminance through compensation for decreasing the grayscale value or data voltage corresponding to the image data of the current pixel. Therefore, the data processing device 140 can improve the pure color luminance ratio.

[0059] The structure of the data processing apparatus 140 according to an embodiment will be described below. The comparison circuit 410 can compare the image data RGB_CUR of the current sub-pixel with the image data RGB_PRE of the previous sub-pixel. The comparison circuit 410 can transmit the comparison result to the data compensation circuit 420.

[0060] Here, the current subpixel can be understood as the subpixel that is driven temporally after the previous subpixel. The current subpixel and the previous subpixel can be on the same line or on different lines. For example, in Figure 3 The previous sub-pixel and the current sub-pixel located on the same line can be the R sub-pixel and the G sub-pixel connected to the first data line DL1, respectively, between the first-1 gate line GL11 and the first-2 gate line GL12. Figure 3 The previous and current sub-pixels located on different lines can be G sub-pixels connected to the first data line DL1 between gate line 1-1 GL11 and gate line 1-2 GL12 and G sub-pixels connected to the first data line DL1 between gate line 2-1 GL21 and gate line 2-2 GL22.

[0061] If the image data RGB_CUR of the current sub-pixel is the same as or different from the image data RGB_PRE of the previous sub-pixel within a predetermined range, the data compensation circuit 420 can compensate the image data RGB_CUR of the current sub-pixel, thereby reducing the data voltage (or gray value) corresponding to the image data RGB_CUR of the current pixel, and thus generating compensated image data RGB'.

[0062] The compensation value calculation circuit 421 can receive the result of comparing the image data RGB_CUR of the current sub-pixel with the image data RGB_PRE of the previous sub-pixel from the comparison circuit 410, and can calculate a compensation value indicating how much the image data RGB_CUR of the current sub-pixel will be compensated. The compensation value calculation circuit 421 can determine whether the grayscale value of the image data RGB_CUR of the current sub-pixel is the same as or similar to the grayscale value of the image data RGB_PRE of the previous sub-pixel (within a predetermined range of difference). If the grayscale value of the image data RGB_CUR of the current sub-pixel is the same as or different from the grayscale value of the image data RGB_PRE of the previous sub-pixel, the compensation value calculation circuit 421 can calculate a compensation value to reduce the grayscale value of the image data RGB_CUR of the current sub-pixel. That is, the compensation value calculation circuit 421 can calculate the reduction amount as the compensation value. The value of the image data RGB_CUR of the current sub-pixel can be reduced by the reduction amount, and compensated image data RGB' including the reduced value can be generated.

[0063] The compensation data generation circuit 422 can generate compensated image data. The compensation data generation circuit 422 can receive a compensation value, including the reduction amount of the image data RGB_CUR of the current sub-pixel, from the compensation value calculation circuit 421. The compensation data generation circuit 422 can reduce the value of the image data RGB_CUR of the current sub-pixel by a reduction amount corresponding to the compensation value, thereby generating compensated image data RGB'.

[0064] Furthermore, the data compensation circuit 420 can adjust the compensation image data RGB' by reflecting the difference between the image data RGB_CUR of the current sub-pixel and the image data RGB_PRE of the previous sub-pixel. As the difference between the image data RGB_CUR of the current sub-pixel and the image data RGB_PRE of the previous sub-pixel decreases, the compensation value calculation circuit 421 of the data compensation circuit 420 can configure a larger reduction in the image data RGB_CUR of the current sub-pixel. Alternatively, as the difference between the image data RGB_CUR of the current sub-pixel and the image data RGB_PRE of the previous sub-pixel increases, the compensation value calculation circuit 421 of the data compensation circuit 420 can configure a smaller reduction in the image data RGB_CUR of the current sub-pixel.

[0065] The data compensation circuit 420 can make additional adjustments to the generated compensated image data RGB' by reflecting the difference between the image data RGB_CUR of the current sub-pixel and the image data RGB_PRE of the previous sub-pixel, or it can generate compensated image data RGB' by reflecting the difference in advance.

[0066] Furthermore, the data compensation circuit 420 can adjust the compensation image data RGB' by reflecting the value of the current sub-pixel's image data RGB_CUR. As the value of the current sub-pixel's image data RGB_CUR increases, the compensation value calculation circuit 421 of the data compensation circuit 420 can configure a larger reduction in the amount of the current sub-pixel's image data RGB_CUR. Alternatively, as the value of the current sub-pixel's image data RGB_CUR decreases, the compensation value calculation circuit 421 of the data compensation circuit 420 can configure a smaller reduction in the amount of the current sub-pixel's image data RGB_CUR.

[0067] The data voltage output circuit 121 can receive the compensated image data RGB' from the data processing device 140, generate a data voltage corresponding to the compensated image data RGB', and output it to the display panel.

[0068] As described above, the data processing device 140 can reduce the grayscale value of the current sub-pixel's image data RGB_CUR when the current sub-pixel's image data RGB_CUR is the same as or the difference between them falls within a predetermined range. The reduction amount can be reduced as the difference between the current sub-pixel's image data RGB_CUR and the previous sub-pixel's image data RGB_PRE increases, and the reduction amount can be increased as the difference between the current sub-pixel's image data RGB_CUR and the previous sub-pixel's image data RGB_PRE decreases.

[0069] Therefore, the brightness of white in the equation for the solid color luminance ratio (i.e., the denominator) becomes smaller, and thus the solid color luminance ratio itself can increase. Therefore, the solid color luminance ratio of a frame including compensated image data RGB' can be higher than that of a frame including image data RGB_CUR of the current subpixel.

[0070] Figure 5 This is a diagram illustrating an example of a lookup table, according to an embodiment, for adjusting the amount of reduction in the grayscale value of a current sub-pixel by reflecting the grayscale value of the current sub-pixel.

[0071] refer to Figure 5 According to the embodiment, the data processing apparatus can use a lookup table (LUT) to determine the amount of reduction in the compensated image data of the current sub-pixel.

[0072] If the grayscale value of a previous sub-pixel is the same as or different from the grayscale value of the current sub-pixel within a predetermined range, the data processing device can decrease the grayscale value of the current sub-pixel. Furthermore, the data processing device can adjust the amount of decrease by reflecting the grayscale value of the current sub-pixel. For this purpose, the data processing device can select the amount of decrease for the grayscale value of the current sub-pixel from a lookup table.

[0073] For example, lookup table 500 can be configured to contain the grayscale value of the current sub-pixel (the Nth grayscale value) and its corresponding reduction amount. According to lookup table 500, if the grayscale value of the current sub-pixel is 255, the data processing device can determine that the reduction amount is 20. In this case, the data processing device can further reduce the grayscale value from 255 by 20, and ultimately reduce the grayscale value by only 20. The same approach can be applied to other grayscale values ​​of the current sub-pixel. The correspondence between other grayscale values ​​of the current sub-pixel and the reduction amount can be predetermined, and lookup table 500 can be pre-stored in a storage circuit.

[0074] Figure 6 This is a flowchart illustrating the operation of a data processing apparatus according to an embodiment.

[0075] refer to Figure 6 The data processing device can compare the image data of the current sub-pixel with the image data of the previous sub-pixel (S602).

[0076] The data processing device can determine whether the image data of the current sub-pixel is the same as the image data of the previous sub-pixel or whether the difference between them falls within a predetermined range (S604).

[0077] If the image data of the current sub-pixel is the same as the image data of the previous sub-pixel, or if the difference between them falls within a predetermined range ("Yes" in S604), the data processing device can compensate the image data of the current sub-pixel (S606). The compensation value calculation circuit of the data processing device can determine the amount of reduction used to indicate how much the image data of the current sub-pixel will be reduced.

[0078] If the image data of the current sub-pixel is not the same as the image data of the previous sub-pixel, and if the difference between them does not fall within a predetermined range ("No" in S604), the data processing device may terminate the operation without compensating the image data of the current sub-pixel.

[0079] In addition, the data processing device can compensate the image data of the current sub-pixel to generate compensated image data (S608). The gray value of the compensated image data can be reduced by the amount of reduction from the gray value of the image data of the current sub-pixel.

[0080] The data processing device can adjust the compensation image data by reflecting the image data of the current sub-pixel (S610). Alternatively, the data processing device can adjust the compensation image data by reflecting the difference between the image data of the current sub-pixel and the image data of the previous sub-pixel (S612). In this process, the data compensation circuit of the data processing device can perform additional adjustments to the generated compensation image data, or it can generate compensation image data by pre-reflecting the image data or difference of the current pixel.

[0081] Figure 7 This is a diagram illustrating the structure of a data processing apparatus according to another embodiment. Figure 8 This is a graph illustrating the change in data voltage between a previous sub-pixel and the current sub-pixel without first compensation, according to another embodiment. Figure 9 This is a graph illustrating the change in data voltage between a previous sub-pixel and a current sub-pixel under the condition of performing a first compensation, according to another embodiment. Figure 10 This is a diagram illustrating an example of a lookup table for generating compensated image data according to another embodiment.

[0082] refer to Figure 7 According to another embodiment, the data processing apparatus 700 may include a first comparison circuit 710a, a second comparison circuit 710b, a first data compensation circuit 720a, a second data compensation circuit 720b, and a storage circuit 730. The first data compensation circuit 720a may include a first compensation value calculation circuit 721a and a first compensation data generation circuit 722a, and the second data compensation circuit 720b may include a second compensation value calculation circuit 721b and a second compensation data generation circuit 722b.

[0083] If the image data of the current sub-pixel differs from the image data of the previous sub-pixel, the data processing device 700 can compensate the image data of the current sub-pixel, thereby increasing or decreasing the data voltage of the image data of the current sub-pixel. This process can be defined as "first compensation".

[0084] Subsequently, if the compensated image data of the current sub-pixel is the same as or similar to the compensated image data of the previous sub-pixel, the data processing device 700 can further compensate the compensated image data of the current sub-pixel to reduce the data voltage or grayscale value of the compensated image data of the current sub-pixel. This process can be defined as "second compensation".

[0085] Therefore, the data processing device 700 can perform a first compensation on the image data of the current sub-pixel, and then perform a second compensation on the compensated image data of the current sub-pixel.

[0086] Here, according to another embodiment, the data processing device 700 can perform both a second compensation and a first compensation to improve the solid color luminance ratio. This is because even if the data processing device 700 increases the luminance of the R, G, and B sub-pixels through the first compensation, there are limitations to the improvement in the solid color luminance ratio. For example, if the luminance is increased at medium or low grayscale values, the solid color luminance ratio improves, but if the luminance is increased further, the gamma curve may be distorted. On the other hand, since the increase in luminance is limited at high grayscale values, the solid color luminance ratio may not change or may not change significantly. Due to this limitation of the first compensation, the data processing device 700 can perform the second compensation.

[0087] In the following description of the structure of the data processing apparatus 700 according to another embodiment, the first comparison circuit 710a can compare the image data RGB_CUR of the current sub-pixel with the image data RGB_PRE of the previous sub-pixel. The first comparison circuit 710a can transmit the comparison result to the first data compensation circuit 720a.

[0088] If the image data RGB_CUR of the current sub-pixel is different from the image data RGB_PRE of the previous sub-pixel, the first data compensation circuit 720a can compensate the image data of the current sub-pixel, causing the data voltage or grayscale value corresponding to the image data of the current sub-pixel to be further increased or decreased, thereby generating compensated image data RGB_PRE'. Here, the operation of increasing the grayscale value and outputting it to the panel is called "overdriving", and the operation of decreasing the grayscale value and outputting it to the panel is called "underdriving".

[0089] Figure 8 This illustrates the change in data voltage between a previous sub-pixel and the current sub-pixel without the data processing device 700 performing a first compensation (overdrive or underdrive). The data voltage Vdata can be applied to the previous sub-pixel at a first voltage V1 level and can be applied to the current sub-pixel at a second voltage V2 level via a data line. The data voltage Vdata can vary from the first voltage V1 to the second voltage V2. Alternatively, the data voltage Vdata can be delayed by a predetermined time, rather than immediately reaching the second voltage V2 from the first voltage V1. The data voltage Vdata can rise at a first time point T1 to reach the second voltage V2 as a target value at a second time point T2, and can be delayed by a period of time from the first time point T1 to the second time point T2.

[0090] on the other hand, Figure 9The diagram shows the change in data voltage Vdata between the previous sub-pixel and the current sub-pixel when the data processing device 700 performs a first compensation (overdrive or underdrive). Because the data processing device 700 performs the first compensation, the delay in data voltage Vdata can be reduced.

[0091] When the data processing device 700 performs the first compensation, a second voltage V2' greater than the second voltage V2 can be applied to the current sub-pixel. That is, a voltage greater than the original target voltage (overdrive) can be applied. The data voltage Vdata of the current sub-pixel can be delayed for a predetermined time to reach the second voltage V2, but the delay time can be shortened. Since the second voltage V2' greater than the second voltage V2 is applied to the current sub-pixel, the time point at which the second voltage V2 is reached can be reduced from the second time point T2 to the second time point T2'.

[0092] If the first compensation for overdriving or underdriving is performed as described above, the time for applying the data voltage can be shortened, thereby quickly transmitting the voltage to each sub-pixel and reducing the charging time of the sub-pixel.

[0093] Return to reference Figure 7 The first compensation value calculation circuit 721a can receive the result of comparing the image data RGB_CUR of the current sub-pixel with the image data RGB_PRE of the previous sub-pixel from the first comparison circuit 710a, and can calculate a compensation value including how much the image data RGB_CUR of the current sub-pixel will be compensated. The first compensation value calculation circuit 721a can determine whether the grayscale value of the image data RGB_CUR of the current sub-pixel is different from the grayscale value of the image data RGB_PRE of the previous sub-pixel. If the grayscale value of the image data RGB_CUR of the current sub-pixel is different from the grayscale value of the image data RGB_PRE of the previous sub-pixel, the first compensation value calculation circuit 721a can calculate a compensation value to increase or decrease the grayscale value of the image data RGB_CUR of the current sub-pixel. For example, if the grayscale value of the image data RGB_CUR of the current sub-pixel is greater than the grayscale value of the image data RGB_PRE of the previous sub-pixel, the first compensation value calculation circuit 721a can calculate a compensation value to increase the grayscale value of the image data RGB_CUR of the current sub-pixel. If the grayscale value of the current sub-pixel's image data RGB_CUR is less than the grayscale value of the previous sub-pixel's image data RGB_PRE, then the first compensation value calculation circuit 721a can calculate a compensation value to reduce the grayscale value of the current sub-pixel's image data RGB_CUR.

[0094] Here, the first compensation value calculation circuit 721a can use a lookup table to calculate the compensation value of the compensation image data RGB_CUR' of the current sub-pixel. The first compensation value calculation circuit 721a can select the compensation value from the value of the image data RGB_PRE of the previous sub-pixel and the value of the image data RGB_CUR of the current sub-pixel in the lookup table.

[0095] refer to Figure 10 The lookup table's row N-1 indicates the image data of the previous sub-pixel, and column N indicates the image data of the current sub-pixel. If the previous sub-pixel's image data RGB_PRE is 32, and the current sub-pixel's image data RGB_CUR is 64, then the compensation image data RGB_CUR' of the current sub-pixel can be 72. Since the compensation image data RGB_CUR' of the current sub-pixel must be increased by 8 to become 72, the compensation value can be +8. On the other hand, if the previous sub-pixel's image data RGB_PRE is 64, and the current sub-pixel's image data RGB_CUR is 32, then the current sub-pixel's image data RGB_CUR' can be 27. Since the current sub-pixel's image data RGB_CUR must be decreased by 5 to become 27, the compensation value can be -5.

[0096] Return to reference Figure 7 The first compensation data generation circuit 722a can generate compensated image data RGB_CUR' for the current sub-pixel. The first compensation data generation circuit 722a can receive compensation values ​​from the first compensation value calculation circuit 721a for decreasing or increasing the image data RGB_CUR of the current sub-pixel. The first compensation data generation circuit 722a can decrease or increase the grayscale value of the image data RGB_CUR of the current sub-pixel by the compensation value, thereby generating the compensated image data RGB_CUR' for the current sub-pixel.

[0097] Image data or compensated image data can be stored in storage circuit 730. First data compensation circuit 720a can perform a first compensation on the image data RGB_CUR of the current sub-pixel to generate compensated image data RGB_CUR' of the current sub-pixel, and can store the compensated image data RGB_CUR' of the current sub-pixel in storage circuit 730. The compensated image data RGB_CUR' of the current sub-pixel stored in storage circuit 730 can be used as the compensated image data RGB_PRE' of the previous sub-pixel for future second compensation. The compensated image data RGB_PRE' of the previous sub-pixel can be read from storage circuit 730 for second compensation, and the compensated image data RGB_PRE' can be sent to second comparison circuit 710b.

[0098] Subsequently, if the compensated image data RGB_CUR' of the current sub-pixel is the same as or different from the compensated image data RGB_PRE' of the previous sub-pixel within a predetermined range, the second data compensation circuit 720b can further compensate the compensated image data RGB_CUR' of the current sub-pixel, thereby reducing the data voltage or grayscale value corresponding to the compensated image data RGB_CUR' of the current sub-pixel, thereby generating the final compensated image data RGB.

[0099] The second comparison circuit 710b can compare the compensated image data RGB_CUR' of the current sub-pixel with the compensated image data RGB_PRE' of the previous sub-pixel. The second comparison circuit 710b can receive the compensated image data RGB_CUR' of the current sub-pixel from the first compensated data generation circuit 722a of the first data compensation circuit 720a, and can read the compensated image data RGB_PRE' of the previous sub-pixel from the storage circuit 730. The second comparison circuit 710b can transmit the comparison result to the second data compensation circuit 720b.

[0100] The second compensation value calculation circuit 721b can receive the comparison result of the current sub-pixel's compensated image data RGB_CUR' and the previous sub-pixel's compensated image data RGB_PRE' from the second comparison circuit 710b, and can calculate the compensation value, including how much the current sub-pixel's compensated image data RGB_CUR' will be compensated. The second compensation value calculation circuit 721b can determine whether the value of the current sub-pixel's compensated image data RGB_CUR' is the same as or similar to the value of the previous sub-pixel's compensated image data RGB_PRE' (within a predetermined range of difference).

[0101] If the value of the current sub-pixel's compensated image data RGB_CUR' is the same as or similar to the grayscale value of the previous sub-pixel's compensated image data RGB_PRE' (i.e., different within a predetermined range), the second compensation value calculation circuit 721b can calculate a compensation value to reduce the grayscale value of the current sub-pixel's compensated image data RGB_CUR'. That is, the second compensation value calculation circuit 721b can calculate a reduction amount as a compensation value. The grayscale value of the current sub-pixel's compensated image data RGB_CUR' can be reduced by the reduction amount, and final compensated image data RGB including the reduced grayscale value can be generated.

[0102] The second compensation data generation circuit 722b can generate the final compensated image data RGB. The second compensation data generation circuit 722b can receive a compensation value, including the reduction amount of the compensated image data RGB_CUR' of the current sub-pixel, from the second compensation value calculation circuit 721b. The second compensation data generation circuit 722b can reduce the grayscale value of the compensated image data RGB_CUR' of the current sub-pixel by a reduction amount corresponding to the compensation value, thereby generating the final compensated image data RGB.

[0103] Additionally, as in one embodiment, the second data compensation circuit 720b according to another embodiment can reflect the difference between the compensated image data RGB_CUR' of the current sub-pixel and the compensated image data RGB_PRE' of the previous sub-pixel, thereby adjusting the compensated image data RGB_CUR' of the current sub-pixel. As the difference between the compensated image data RGB_CUR' of the current sub-pixel and the compensated image data RGB_PRE' of the previous sub-pixel decreases, the second compensation value calculation circuit 721b of the second data compensation circuit 720b can configure a larger reduction in the compensated image data RGB_CUR' of the current sub-pixel. Alternatively, as the difference between the compensated image data RGB_CUR' of the current sub-pixel and the compensated image data RGB_PRE' of the previous sub-pixel increases, the second compensation value calculation circuit 721b of the second data compensation circuit 720b can configure a smaller reduction in the compensated image data RGB_CUR' of the current sub-pixel.

[0104] The second data compensation circuit 720b can reflect the difference between the compensation image data RGB_CUR' of the current sub-pixel and the compensation image data RGB_PRE' of the previous sub-pixel in the generated final compensation image data RGB, and can make additional adjustments, or can reflect the difference in advance to generate the final compensation image data RGB.

[0105] Furthermore, the second data compensation circuit 720b can adjust the final compensation image data RGB' by reflecting the grayscale value of the compensation image data RGB_CUR' of the current sub-pixel. The second compensation value calculation circuit 721b of the second data compensation circuit 720b can receive the compensation image data RGB_CUR' of the current sub-pixel from the first compensation data generation circuit 722a of the first data compensation circuit 720a. As the value of the compensation image data RGB_CUR' of the current sub-pixel increases, the second compensation value calculation circuit 721b of the second data compensation circuit 720b can configure a larger reduction in the compensation image data RGB_CUR' of the current sub-pixel. Optionally, as the value of the compensation image data RGB_CUR' of the current sub-pixel decreases, the second compensation value calculation circuit 721b of the second data compensation circuit 720b can configure a smaller reduction in the compensation image data RGB_CUR' of the current sub-pixel.

[0106] As described above, if the compensation image data RGB_CUR' of the current sub-pixel is the same as the compensation image data RGB_PRE' of the previous sub-pixel, or if the difference between them falls within a predetermined range, the data processing device 700 may reduce the value of the compensation image data RGB_CUR' of the current sub-pixel.

[0107] Therefore, the brightness of white in the equation for the solid color luminance ratio (i.e., the denominator) becomes smaller, and thus the solid color luminance ratio itself can increase. Therefore, the solid color luminance ratio of a frame that includes the final compensated image data "RGB" can be higher than the solid color luminance ratio of a frame that includes the image data "RGB_CUR" of the current subpixel.

[0108] Figure 11 This is a flowchart illustrating the operation of a data processing apparatus according to another embodiment.

[0109] refer to Figure 11 The data processing device can compare the image data of the current sub-pixel with the image data of the previous sub-pixel, thereby performing a first compensation on the image data of the current sub-pixel. Subsequently, the data processing device can perform a second compensation on the result of the first compensation.

[0110] For the first compensation, the data processing device can compare the image data of the current sub-pixel with the image data of the previous sub-pixel (S1102). The data processing device can determine whether there is a difference between the image data of the current sub-pixel and the image data of the previous sub-pixel. The grayscale value of the image data of the current sub-pixel can be compared with the grayscale value of the image data of the previous sub-pixel.

[0111] If the image data of the current sub-pixel is different from the image data of the previous sub-pixel ("Yes" in S1104), the data processing device can compensate the image data of the current sub-pixel to generate compensated image data for the current sub-pixel (S1106). The first data calculation circuit can calculate a compensation value for increasing or decreasing the data voltage or grayscale value corresponding to the image data of the current sub-pixel. If the difference between the grayscale value of the current sub-pixel and the grayscale value of the previous sub-pixel falls outside a predetermined range, the data processing device can determine that the image data of the current sub-pixel is different from the image data of the previous sub-pixel.

[0112] If the image data of the current sub-pixel is no different from the image data of the previous sub-pixel ("No" in S1104), then there is no need to perform first compensation on the image data of the current sub-pixel. Instead, instead of compensation image data for the current sub-pixel, the data processing device may perform second compensation on the image data of the current sub-pixel (S1108).

[0113] Next, for the second compensation, the data processing device can compare the compensation image data of the current sub-pixel with the compensation image data of the previous sub-pixel (S1108).

[0114] The data processing device can determine whether the compensation image data of the current sub-pixel is the same as the compensation image data of the previous sub-pixel or whether the difference between them falls within a predetermined range (S1110).

[0115] If the compensation image data of the current sub-pixel is the same as the compensation image data of the previous sub-pixel, or if the difference between them falls within a predetermined range ("Yes" in S1110), the data processing device may further compensate the compensation image data of the current sub-pixel (S1112). The data processing device may determine the amount of reduction used to indicate how much the compensation image data of the current sub-pixel should be reduced.

[0116] On the other hand, if the compensation image data of the current sub-pixel is not the same as the compensation image data of the previous sub-pixel, and if the difference between them falls outside a predetermined range ("No" in S1110), the data processing device may terminate the operation without performing a second compensation on the compensation image data of the current sub-pixel.

[0117] Furthermore, the data processing device can adjust the compensation image data of the current sub-pixel by reflecting the grayscale value of the compensation image data of the current sub-pixel (S1114). Additionally, the data processing device can adjust the compensation image data of the current sub-pixel by reflecting the difference between the compensation image data of the current sub-pixel and the compensation image data of the previous sub-pixel (S1116). In this process, the second data compensation circuit can perform additional adjustments on the generated compensation image data, or it can generate compensation image data by pre-reflecting the grayscale value or the difference of the compensation image data of the current pixel.

[0118] Cross-reference to related applications

[0119] This application claims priority to Korean Patent Application No. 10-2020-0029564, filed on March 10, 2020, the entire contents of which are incorporated herein by reference.

Claims

1. A data processing apparatus for generating image data of first and second sub-pixels of different colors connected to a data line, the data processing apparatus comprising: A first data compensation circuit is configured to generate compensated image data, which is used to apply overdriving or underdriving to the grayscale values ​​of image data of the first sub-pixel and the second sub-pixel driven sequentially after the first sub-pixel. as well as The second data compensation circuit is configured to reduce the gray value of the compensation image data of the second sub-pixel when the gray value of the compensation image data of the first sub-pixel is the same as or different within a predetermined range from the gray value of the compensation image data of the second sub-pixel. Wherein, the pure color luminance ratio of the frame including the grayscale value of the compensated image data of the second sub-pixel is higher than that of the frame including the grayscale value of the image data of the second sub-pixel, and The pure color brightness ratio is defined as the ratio of the sum of the brightness values ​​of red, green and blue to the brightness value of white.

2. The data processing apparatus according to claim 1, wherein, The second data compensation circuit reduces the gray value of the compensation image data of the second sub-pixel by reflecting the difference between the gray value of the compensation image data of the first sub-pixel and the gray value of the compensation image data of the second sub-pixel.

3. The data processing apparatus according to claim 2, wherein, The second data compensation circuit reduces the gray value of the compensation image data of the second sub-pixel by a larger amount as the difference between the gray value of the compensation image data of the first sub-pixel and the gray value of the compensation image data of the second sub-pixel decreases.

4. The data processing apparatus according to claim 2, wherein, The second data compensation circuit reduces the gray value of the compensation image data of the second sub-pixel by a smaller amount as the difference between the gray value of the compensation image data of the first sub-pixel and the gray value of the compensation image data of the second sub-pixel increases.

5. The data processing apparatus according to claim 1, wherein, The second data compensation circuit determines the amount of reduction in the grayscale value of the compensated image data of the second sub-pixel by reflecting the grayscale value of the compensated image data of the second sub-pixel.

6. The data processing apparatus according to claim 5, wherein, The second data compensation circuit reduces the gray value of the compensated image data of the second sub-pixel by a larger amount as the gray value of the compensated image data of the second sub-pixel increases.

7. The data processing apparatus according to claim 5, wherein, The second data compensation circuit reduces the gray value of the compensated image data of the second sub-pixel by an even smaller amount as the gray value of the compensated image data of the second sub-pixel decreases.

8. The data processing apparatus according to claim 5, wherein, The second data compensation circuit uses a lookup table to determine the amount of reduction in the grayscale value of the compensated image data of the second sub-pixel.

9. The data processing apparatus according to claim 1, wherein, The first sub-pixel and the second sub-pixel are arranged in the same row on the display panel and are connected to different gate lines.

10. A data processing apparatus for generating image data of first and second sub-pixels of different colors connected to a data line, the data processing apparatus comprising: A comparison circuit is configured to compare image data of a first sub-pixel with image data of a second sub-pixel driven sequentially after the first sub-pixel. as well as A data compensation circuit is configured to reduce the grayscale value of the image data of the second sub-pixel when the grayscale value of the image data of the first sub-pixel is the same as or different from the grayscale value of the image data of the second sub-pixel within a predetermined range, thereby generating compensated image data for the second sub-pixel. Wherein, the pure color luminance ratio of the frame including the grayscale value of the compensated image data of the second sub-pixel is higher than that of the frame including the grayscale value of the image data of the second sub-pixel, and The pure color brightness ratio is defined as the ratio of the sum of the brightness values ​​of red, green and blue to the brightness value of white.

11. The data processing apparatus according to claim 10, wherein, The data compensation circuit adjusts the amount by which the gray value of the second sub-pixel's image data is reduced, based on the difference between the gray value of the first sub-pixel's image data and the gray value of the second sub-pixel's image data.

12. The data processing apparatus according to claim 10, wherein, The data compensation circuit adjusts the amount by which the grayscale value of the image data of the second sub-pixel is reduced, based on the grayscale value of the image data of the second sub-pixel.

13. The data processing apparatus according to claim 10, wherein, The data line intersects with multiple gate lines, and The first sub-pixel and the second sub-pixel are connected to the data line and to the corresponding gate line among the plurality of gate lines.

14. The data processing apparatus according to claim 10, wherein, The first sub-pixel and the second sub-pixel are arranged in the same row on the display panel and are connected to different gate lines.

Images