# US 10,121,425 B2 · Adaptive black clipping circuit, display device including the same and adaptive black clipping method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,121,425 B2 - Document ID: US10121425B2 - Status: Granted - Kind: B2 - Application number: 14/825,376 - Filed: 2015-08-13 - Published: 2016-04-28 - Granted: 2018-11-06 - Earliest claimed: 2014-10-24 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Ik-Hyun Ahn; Yoon-Gu Kim; Woo-Joo Lee; Bong-Im Park - Web page: https://patentgrep.com/patent/US10121425B2 ## CPC - G09G 3/3614: {Control of polarity reversal in general} - G09G 3/3406: {Control of illumination source (illumination devices structurally associated with liquid crystal cells G02F1/1336)} - G09G 3/3607: {for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels (display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127)} - G09G 3/3648: {using an active matrix (G09G3/367 - G09G3/3696 take precedence)} - G09G 3/3696: {Generation of voltages supplied to electrode drivers} - G09G 2310/0251: Precharge or discharge of pixel before applying new pixel voltage - G09G 2310/0286: Details of a shift registers arranged for use in a driving circuit - G09G 2320/0209: Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display - G09G 2320/0242: Compensation of deficiencies in the appearance of colours - G09G 2320/0271: Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping - G09G 2320/043: Preventing or counteracting the effects of ageing - G09G 2320/066: for control of contrast - G09G: ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION (arrangements for transferring data between digital computers and displays G06F3/14; static indicating arrangements comprising an association of a number of separate sources or light control cells G09F9/00; static indicating arrangements comprising integral associations of a number of light sources H01J, H01K, H10H, H05B33/12; scanning, transmission or reproduction of documents or the like, e.g. facsimile transmission, details thereof H04N1/00) ## Abstract An adaptive black clipping circuit in a display device includes a data corrector, a register, a pattern detector and a clipping selector. The data corrects input image data to generate corrected image data such that the corrected image data is equal to or greater than a black clipping value where the black clipping value corresponds to the input image data having a grayscale value of zero and the black clipping value is greater than zero. The register stores and provides configuration data. The pattern detector generates a pattern detection signal based on the input image data corresponding to a plurality of rows. The clipping selector selects one of the corrected image data and the configuration data in response to the pattern detection signal to provide output image data. ## Claims ### Claim 1 An adaptive black clipping circuit in a display device, comprising: a data corrector configured to correct input image data to generate corrected image data such that the corrected image data is greater than or equal to a black clipping value, the black clipping value is greater than zero and corresponds to the input image data having a grayscale value of zero; a register configured to store and provide configuration data; a pattern detector configured to generate a pattern detection signal based on the input image data corresponding to a plurality of pixel rows; and a clipping selector configured to select one of the corrected image data and the configuration data in response to the pattern detection signal to provide output image data, wherein the pattern detector comprises: a first detector configured to receive a first input image data of a current pixel row to generate a first detection signal that is activated when the first input image data is black data; a buffer configured to receive the first input image data to output second input image data of a previous pixel row adjacent to the current pixel row; a second detector configured to receive the second input image data to generate a second detection signal that is activated when the second input image data is black data; and a logic gate configured to perform a logic operation on the first detection signal and the second detection signal to generate the pattern detection signal that is activated when both of the first detection signal and the second detection signal are activated. ### Claim 2 (depends on 1) The adaptive black clipping circuit of claim 1, wherein the pattern detector activates the pattern detection signal when grayscale values of red input image data, green input image data, and blue input image data are zero with respect to a current pixel row and a previous pixel row adjacent to the current pixel row. ### Claim 3 (depends on 1) The adaptive black clipping circuit of claim 1, wherein the configuration data is set to a value smaller than the black clipping value. ### Claim 4 (depends on 1) The adaptive black clipping circuit of claim 1, wherein the configuration data is set to a value of zero. ### Claim 5 (depends on 1) The adaptive black clipping circuit of claim 1, wherein the data corrector comprises: a lookup table configured to store corrected grayscale values respectively corresponding to grayscale values of the input image data; and an extractor configured to extract the corrected grayscale values corresponding to the grayscale values of the input image data from the lookup table to output the corrected image data. ### Claim 6 (depends on 5) The adaptive black clipping circuit of claim 5, wherein each of the corrected grayscale values is common with respect to all positions on a display panel. ### Claim 7 (depends on 6) The adaptive black clipping circuit of claim 6, wherein the black clipping value comprises a red black clipping value corresponding to the grayscale value of zero of a red input image data, a green black clipping value corresponding to the grayscale value of zero of a green input image data, and a blue black clipping value corresponding to the grayscale value of zero of a blue input image data. ### Claim 8 (depends on 1) The adaptive black clipping circuit of claim 1, wherein the data corrector comprises: a lookup table configured to store corrected grayscale values respectively corresponding to grayscale values of the input image data; an extractor configured to extract at least one of a first extraction value and a second extraction value from the lookup table based on position information indicating a position of the input image data on a display panel included in the display device, the first extraction value corresponding to the grayscale value of zero of the input image data and the second extraction value corresponding to a grayscale value other than zero of the input image data; an interpolator configured to generate an interpolation value based on the first extraction value; and an output selector configured to select one of the interpolation value and the second extraction value in response to a selection signal to output the corrected image data. ### Claim 9 (depends on 8) The adaptive black clipping circuit of claim 8, wherein the black clipping value among the corrected grayscale values comprises a plurality of regional black clipping values respectively corresponding to a plurality of clipping regions on the display panel included in the display device. ### Claim 10 (depends on 9) The adaptive black clipping circuit of claim 9, wherein, when the input image data has the grayscale value of zero, the extractor outputs at least one value, among the regional black clipping values, as the first extraction value based on the position information. ### Claim 11 (depends on 10) The adaptive black clipping circuit of claim 10, wherein, when the position indicated by the position information is included in one clipping region among the clipping regions, the extractor outputs one value corresponding to the one clipping region among the regional black clipping values as the first extraction value and the interpolator outputs the one value as the interpolation value. ### Claim 12 (depends on 10) The adaptive black clipping circuit of claim 10, wherein, when the position indicated by the position information is included in one intermediate region between the clipping regions, the extractor outputs two or more values corresponding to the one intermediate region among the regional black clipping values as the first extraction value and the interpolator interpolates the two or more values to output as the interpolation value. ### Claim 13 (depends on 8) The adaptive black clipping circuit of claim 8, wherein each of the other corrected grayscale values except the black clipping value is common with respect to all positions on the display panel. ### Claim 14 (depends on 13) The adaptive black clipping circuit of claim 13, wherein, when the input image data has a grayscale value other than zero, the extractor outputs one value corresponding to the grayscale value of the input image data among the corrected grayscale values as the second extraction value regardless of the position of the input image data on the display panel. ### Claim 15 (depends on 1) The adaptive black clipping circuit of claim 1, wherein the first detector comprises: a first comparator configured to generate a first comparison signal that is activated to a logic high level when red input image data of the current pixel row has a grayscale value of zero; a second comparator configured to generate a second comparison signal that is activated to the logic high level when green input image data of the current pixel row has the grayscale value of zero; a third comparator configured to generate a third comparison signal that is activated to the logic high level when blue input image data of the current pixel row has the grayscale value of zero; and a first AND logic gate configured to perform an AND logic operation on the first comparison signal, the second comparison signal, and the third comparison signal to generate the first detection signal. ### Claim 16 (depends on 15) The adaptive black clipping circuit of claim 15, wherein the second detector comprises: a fourth comparator configured to generate a fourth comparison signal that is activated to the logic high level when the red input image data of the previous pixel row has the grayscale value of zero; a fifth comparator configured to generate a fifth comparison signal that is activated to the logic high level when green input image data of the previous pixel row has the grayscale value of zero; a sixth comparator configured to generate a sixth comparison signal that is activated to the logic high level when blue input image data of the previous pixel row has the grayscale value of zero; and a second AND logic gate configured to perform an AND logic operation on the fourth comparison signal, the fifth comparison signal, and the sixth comparison signal to generate the second detection signal. ### Claim 17 A display device comprising: a display panel comprising a plurality of pixels coupled to a plurality of data lines and a plurality of gate lines; an adaptive black clipping circuit configured to provide output image data based on input image data; a data driver configured to output data voltages corresponding to the output image data to the plurality of data lines; and a gate driver configured to output gate driving signals to the plurality of gate lines, wherein the adaptive black clipping circuit comprises: a data corrector configured to correct the input image data to generate corrected image data such that the corrected image data is greater than or equal to a black clipping value, the black clipping value is greater than zero and corresponds to the input image data having a grayscale value of zero; a register configured to store and provide configuration data; a pattern detector configured to generate a pattern detection signal based on the input image data corresponding to a plurality of pixel rows; and a clipping selector configured to select one of the corrected image data and the configuration data in response to the pattern detection signal to provide the output image data, wherein the pattern detector comprises: a first detector configured to receive a first input image data of a current pixel row to generate a first detection signal that is activated when the first input image data is black data; a buffer configured to receive the first input image data to output second input image data of a previous pixel row adjacent to the current pixel row; a second detector configured to receive the second input image data to generate a second detection signal that is activated when the second input image data is black data; and a logic gate configured to perform a logic operation on the first detection signal and the second detection signal to generate the pattern detection signal that is activated when both of the first detection signal and the second detection signal are activated. ### Claim 18 (depends on 17) The display device of claim 17, wherein the data driver delays outputting the data voltages to the plurality of data lines sequentially to reduce electromagnetic interferences between the plurality of data lines.