# US 7,612,750 B2 · Liquid crystal display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,612,750 B2 - Document ID: US7612750B2 - Status: Granted - Kind: B2 - Application number: 10/289,832 - Filed: 2002-11-07 - Published: 2003-05-29 - Granted: 2009-11-03 - Earliest claimed: 2001-11-28 - Assignees: Sharp Kabushiki Kaisha - Inventors: Akihisa Iwamoto; Hideki Morii; Kazushige Miyamoto - Web page: https://patentgrep.com/patent/US7612750B2 ## CPC - G09G 3/3648: {using an active matrix (G09G3/367 - G09G3/3696 take precedence)} - G09G 3/3614: {Control of polarity reversal in general} - 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 2330/08: Fault-tolerant or redundant circuits, or circuits in which repair of defects is prepared - 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 A liquid crystal display device includes: scanning wires, provided so as to correspond to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; and signal wires to which data signals are applied, wherein the scanning wires and the signal wires cross each other. TFTs, electrically connected to the scanning wires and the signal wires, each of which is provided in the vicinity of an intersection of the scanning wire and the signal wire, and the TFTs are connected to pixel electrodes. A dummy pixel driven by a dummy signal wire is provided externally adjacent to an endmost pixel column. This brings about a matrix type liquid crystal display device that equalizes capacitive conditions of all the signal wires to each other and can prevent deterioration of display quality that is brought about by a specific portion differently displayed. ## Claims ### Claim 1 A liquid crystal display device comprising: scanning wires, provided corresponding to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; signal wires, provided corresponding to the pixels so as to cross the scanning wires, to which data signals are applied; switching elements, electrically connected to the scanning wires and the signal wires, each of which is provided in a vicinity of each of intersections of the scanning wires and the signal wires; pixel electrodes connected to the switching elements; a dummy pixel, provided externally adjacent to an endmost pixel column, that is driven by a dummy signal wire; and wherein the dummy signal wire is connected to a first signal wire, the dummy signal wire is externally adjacent to an endmost signal wire of the endmost pixel column, and the first signal wire is not adjacent to the endmost signal wire; wherein the first signal wire is selected so that it leads signals of the same color and polarity as the dummy signal wire so as to thereby cause the pixel of the endmost signal wire to be driven under similar conditions as pixels that are more centrally located; and wherein the color and polarity of the signals of the dummy signal wire are determined based on the specific combination of color and polarity in an AC driving cycle for the signal wires for an adjacent wire that is externally adjacent to the endmost signal wire. ### Claim 2 (depends on 1) The liquid crystal display device as set forth in claim 1, further comprising a dummy pixel driving output buffer connected to the dummy signal wire. ### Claim 3 (depends on 1) The liquid crystal display device as set forth in claim 1, wherein the first signal wire is one of the signal wires, that is a 3n (n=1, 2, . . . )th line from the dummy signal wire, in a case of a gate line inversion driving mode, where n is a natural number. ### Claim 4 (depends on 3) The liquid crystal display device as set forth in claim 3 further comprising a dummy pixel driving output buffer connected to the dummy signal wire, and wherein the first signal wire is connected to the dummy pixel output buffer. ### Claim 5 (depends on 1) The liquid crystal display device as set forth in claim 1, wherein the first signal wire is one of the signal wires, that is a 6n (n=1, 2, . . . )th line from the dummy signal wire, in a case of a dot inversion driving mode or a source inversion driving mode, where n is a natural number. ### Claim 6 (depends on 5) The liquid crystal display device as set forth in claim 5 further comprising a dummy pixel driving output buffer connected to the dummy signal wire, and wherein the first signal wire is connected to the dummy pixel driving output buffer. ### Claim 7 (depends on 1) The liquid crystal display device of claim 1, wherein the first signal wire is selected so that it leads signals of the same color and polarity as the dummy signal wire line so as to thereby cause the pixel of the endmost signal wire to be driven under similar conditions as another pixel that is adjacent to the first signal wire. ### Claim 8 (depends on 1) The liquid crystal display device of claim 1, wherein the first signal wire is selected so that the signals passing through the first signal wire and through the dummy signal line are such that capacitive coupling of the endmost signal wire and the adjacent dummy pixel is essentially equalized to the influence caused in a second signal wire adjacent to the first signal line by the capacitive coupling of the second signal line and the first signal wire. ### Claim 9 (depends on 8) The liquid crystal display device of claim 8, wherein the second signal wire leads signals of the same color and polarity as the endmost signal wire. ### Claim 10 A liquid crystal display device comprising: scanning wires, provided corresponding to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; signal wires, provided corresponding to the pixels so as to cross the scanning wires, to which data signals are applied; switching elements, electrically connected to the scanning wires and the signal wires, each of which is provided in a vicinity of each of intersections of the scanning wires and the signal wires; pixel electrodes connected to the switching elements; a dummy pixel, provided externally adjacent to an endmost pixel column, that is driven by a dummy signal wire; a dummy pixel driving output buffer connected to the dummy signal wire; wherein the dummy signal wire connected to the dummy pixel is connected to corresponding one of the signal wires leading the data signals of same color and polarity, in according with a cycle at which specific combination of color and polarity in ac driving appears; a source driver for supplying the data signals to the signal wires; and a spare wire driving output buffer, provided on the source driver in advance, that connects a spare wire for restoring one of the signal wires that has been disconnected, wherein the spare wire driving output buffer is used also as a dummy pixel driving output buffer. ### Claim 11 A liquid crystal display device comprising: scanning wires, provided corresponding to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; signal wires, provided corresponding to the pixels so as to cross the scanning wires, to which data signals are applied; switching elements, electrically connected to the scanning wires and the signal wires, each of which is provided in a vicinity of each of intersections of the scanning wires and the signal wires; pixel electrodes connected to the switching elements; a dummy signal wire provided externally adjacent to an endmost pixel column; wherein the dummy signal wire is connected to an output buffer; wherein the dummy signal wire is connected to a first signal wire, the dummy signal wire is externally adjacent to an endmost signal wire of the endmost pixel column, and the first signal wire is not adjacent to the end most signal wire; wherein the first signal wire is selected so that it leads signal of the same color and polarity as the dummy signal wire and so as to thereby cause the pixel of the endmost signal wire to be driven under similar conditions as pixels that are more centrally located; and wherein the color and polarity of the signals of the dummy signal wire are determined based on the specific combination of color and polarity in an AC driving cycle for the signal wires for an adjacent x ire that is externally adjacent to the endmost signal wire. ### Claim 12 (depends on 11) The liquid crystal display device as set forth in claim 11, wherein the first signal wire is one of the signal wires, that is a 3n (n=1, 2, . . . )th line from the dummy signal wire, in a case of a gate line inversion driving mode, where n is a natural number. ### Claim 13 (depends on 11) The liquid crystal display device as set forth in claim 11, wherein the first signal wire is one of the signal wires, that is a 6n (n=1, 2, . . . )th line from the dummy signal wire, in a case of a dot inversion driving mode or a source inversion driving mode, where n is a natural number. ### Claim 14 (depends on 11) The liquid crystal display device as set forth in claim 11, wherein the first signal wire is centrally disposed in the liquid crystal display device. ### Claim 15 (depends on 11) The liquid crystal display device of claim 11, wherein the first signal wire is selected so that it leads signals of the same color and polarity as the dummy signal wire line so as to thereby cause the pixel of the endmost signal wire to be driven under similar conditions as another pixel that is adjacent to the first signal wire. ### Claim 16 (depends on 11) The liquid crystal display device of claim 11, wherein the first signal wire is selected so that the signals passing through the first signal wire and through the dummy signal line are such that capacitive coupling of the endmost signal wire and the adjacent dummy pixel is essentially equalized to the influence caused in a second signal adjacent to the first signal line by the capacitive coupling of the second signal line and the first signal wire. ### Claim 17 (depends on 16) The liquid crystal display device of claim 16, wherein the second signal wire leads signals of the same color and polarity as the endmost signal wire. ### Claim 18 A liquid crystal display device comprising: scanning wires, provided corresponding to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; signal wires, provided corresponding to the pixels so as to cross the scanning wires, to which data signals are applied; switching elements, electrically connected to the scanning wires and the signal wires, each of which is provided in a vicinity of each of intersections of the scanning wires and the signal wires; a dummy signal wire provided externally adjacent to an endmost pixel column; wherein the dummy signal wire is connected to a dummy pixel driving output buffer; a source driver for supplying the data signals to the signal wires; a spare wire driving output buffer, provided on the source driver in advance, that connects a spare wire for restoring one of the signal wires that has been disconnected; and wherein the spare wire driving output buffer is used also as a dummy pixel driving output buffer. ### Claim 19 A liquid crystal display device comprising: scanning wires, provided corresponding to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; signal wires, provided corresponding to the pixels so as to cross the scanning wires, to which data signals are applied; switching elements, electrically connected to the scanning wires and the signal wires, each of which is provided in a vicinity of each of intersections of the scanning wires and the signal wires; pixel electrodes connected to the switching elements; a dummy signal wire provided externally adjacent to an endmost pixel column; wherein the dummy signal wire is connected to an output buffer; wherein the dummy signal wire is connected to corresponding one of the signal wires leading the data signals of same color and polarity, in accordance with a cycle at which specific combination of color and polarity in ac driving appears; wherein the dummy signal wire is connected to one of the signal wires, that is a 3n (n=1, 2, . . . )th line from the dummy signal wire, in a case of a gate line inversion driving mode, where n is a natural number; a source driver for supplying the data signals to the signal wires; and a spare wire driving output buffer, provided on the source driver in advance, that connects a spare wire for restoring one of the signal wires that has been disconnected, wherein the spare wire driving output buffer is used also as a dummy pixel driving output buffer. ### Claim 20 A liquid crystal display device comprising: scanning wires, provided corresponding to a plurality of pixels disposed in a matrix manner, to which scanning signals are applied; signal wires, provided corresponding to the pixels so as to cross the scanning wires, to which data signals are applied; switching elements, electrically connected to the scanning wires and the signal wires, each of which is provided in a vicinity of each of intersections of the scanning wires and the signal wires; pixel electrodes connected to the switching elements; a dummy signal wire provided externally adjacent to an endmost pixel column; wherein the dummy signal wire is connected to an output buffer; wherein the dummy signal wire is connected to corresponding one of the signal wires leading the data signals of same color and polarity, in accordance with a cycle at which specific combination of color and polarity in ac driving appears; wherein the dummy signal wire is connected to one of the signal wires, that is a 6n (n=1, 2, . . . )th line from the dummy signal wire, in a case of a dot inversion driving mode or a source inversion driving mode, where n is a natural number; a source driver for supplying the data signals to the signal wires; and a spare wire driving output buffer, provided on the source driver in advance, that connects a spare wire for restoring one of the signal wires that has been disconnected, wherein the spare wire driving output buffer is used also as a dummy pixel driving output buffer.