# US 5,708,454 A · Matrix type display apparatus and a method for driving the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,708,454 A - Document ID: US5708454A - Status: Granted - Kind: A - Application number: 08/250,493 - Filed: 1994-05-27 - Granted: 1998-01-13 - Earliest claimed: 1993-05-31 - Assignees: Sharp Kabushiki Kaisha - Inventors: Kenichi Katoh; Hiroshi Yoneda - Web page: https://patentgrep.com/patent/US5708454A ## CPC - G09G 3/3688: {suitable for active matrices only} - G09G 3/3648: {using an active matrix (G09G3/367 - G09G3/3696 take precedence)} - G09G 3/3614: {Control of polarity reversal in general} - G09G 2300/043: Compensation electrodes or other additional electrodes in matrix displays related to distortions or compensation signals, e.g. for modifying TFT threshold voltage in column driver - G09G 2300/0809: Several active elements per pixel in active matrix panels - G09G 2310/0248: Precharge or discharge of column electrodes before or after applying exact column voltages - G09G 2310/0251: Precharge or discharge of pixel before applying new pixel voltage - 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 matrix type display apparatus includes pixel electrodes arranged in a matrix, data signal lines and scanning signal lines for driving the pixel electrodes, and a data signal line driving circuit. The data signal line driving circuit includes sampling capacitors for keeping sampled data obtained by sequentially sampling image data over one horizontal scanning period, holding capacitors for holding the sampled data transmitted from the sampling capacitors upon termination of the horizontal scanning period and then outputting the sampled data to data signal lines, and a precharging circuit for precharging the corresponding holding capacitors by applying a predetermined voltage to the holding capacitors before the sampled data is transmitted to the holding capacitors. ## Claims ### Claim 1 A matrix type display apparatus, comprising: pixel electrodes arranged in a matrix; data signal lines and scanning signal lines for driving the pixel electrodes; and a data signal line driving circuit including: sampling capacitors for keeping sampled data obtained by sequentially sampling image data over one horizontal scanning period; holding capacitors for holding the sampled data transmitted from the sampling capacitors upon termination of the horizontal scanning period and then outputting the sampled data to data signal lines as a data signal; and precharging means for precharging the corresponding holding capacitors by applying a predetermined voltage to the holding capacitors before the sampled data is transmitted to the holding capacitors. ### Claim 2 (depends on 1) A matrix type display apparatus according to claim 1, wherein each of the precharging means includes: a precharging switch temporarily turned on by a precharging signal before the sampled data is transmitted to the holding capacitor; and a precharging line connected to the holding capacitor through the precharging switch and loaded with a predetermined voltage. ### Claim 3 (depends on 1) A matrix type display apparatus according to claim 1, wherein the polarity of the potential for the precharging is the same as the polarity of the data signal. ### Claim 4 (depends on 1) A matrix type display apparatus according to claim 1, wherein the potential for the precharging has an intermediate value between extreme values of the potential of the data signal. ### Claim 5 A matrix type display apparatus, comprising: pixel electrodes arranged in a matrix; data signal lines and scanning signal lines for driving the pixel electrodes; and a data signal line driving circuit including: sampling capacitors for keeping sampled data obtained by sequentially sampling image data over one horizontal scanning period; holding capacitors for holding the sampled data transmitted during one horizontal scanning period and then outputting the sampled data to data signal lines as a data signal; and precharging means for precharging the corresponding holding capacitors by applying a predetermined voltage to the holding capacitors and the data signal lines before the sampled data is transmitted to the holding capacitors. ### Claim 6 (depends on 5) A matrix type display apparatus according to claim 5, wherein each of the precharging means includes: a precharging switch temporarily turned on by a precharging signal before the sampled data is transmitted to the holding capacitor; and a precharging line connected to the holding capacitor through the precharging switch and loaded with a predetermined voltage. ### Claim 7 (depends on 5) A matrix type display apparatus according to claim 5, wherein the polarity of the potential for the precharging is the same as the polarity of the data signal. ### Claim 8 (depends on 5) A matrix type display apparatus according to claim 5, wherein the potential for the precharging has an intermediate value between extreme values of the potential of the data signal. ### Claim 9 A matrix type display apparatus comprising: pixel electrodes arranged in a matrix; data signal lines and scanning signal lines for driving the pixel electrodes; and a data signal line driving circuit including sampling capacitors for keeping sampled data obtained by sequentially sampling image data over one horizontal scanning period and then outputting the sampled data to data signal lines as a data signal, and precharging means for precharging the corresponding data signal lines by applying a predetermined voltage to the data signal lines before the sampled data is output to the data signal lines, the predetermined voltage for a corresponding data signal line having a polarity that is the same as a polarity of the sampled data output to the corresponding data signal line, even if the polarity of the sampled data is inverted. ### Claim 10 (depends on 9) A matrix type display apparatus according to claim 9, wherein each of the precharging means includes: a precharging switch temporarily turned on by a precharging signal before the sampled data is output to the data signal line; and a precharging line connected to the data signal line through the precharging switch and loaded with a predetermined voltage. ### Claim 11 (depends on 9) A matrix type display apparatus according to claim 9, wherein the potential for the precharging has an intermediate value between extreme values of the potential of the data signal. ### Claim 12 A matrix type display apparatus, comprising: pixel electrodes arranged in a matrix; data signal lines and scanning signal lines for driving the pixel electrodes; holding capacitors for holding data and for outputting the data to corresponding data signal lines; pixel switches each turned on by a signal sent through the corresponding scanning signal line for supplying a current from the corresponding data signal line to the corresponding pixel electrode; and precharging means for precharging the corresponding pixel electrodes by applying a predetermined voltage to the corresponding pixel electrodes before the corresponding pixel switch is turned on by the signal sent through the corresponding scanning signal lines, the predetermined voltage for a corresponding pixel electrode having a polarity that is the same as a polarity of the data output to the corresponding data signal line of the corresponding pixel electrode, even if the polarity of the data is inverted. ### Claim 13 (depends on 12) A matrix type display apparatus according to claim 12, wherein each of the precharging means includes a precharging switch disposed for each pixel electrode and turned on by one of the scanning signal lines selected prior to the corresponding scanning signal line for turning on the pixel switch for the corresponding pixel electrode, and the corresponding pixel electrode is connected to a data signal line adjacent to the corresponding data signal line through the precharging switch. ### Claim 14 (depends on 12) A matrix type display apparatus according to claim 12, wherein each of the precharging means includes: a precharging switch disposed for each pixel electrode and turned on by one of the scanning signal lines selected prior to the corresponding scanning signal line for turning on the pixel switch for the corresponding pixel electrode; and a precharging line connected to the corresponding pixel electrode through the precharging switch and loaded with the predetermined voltage. ### Claim 15 (depends on 12) A matrix type display apparatus according to claim 12, wherein the potential for the precharging has an intermediate value between extreme values of the potential of the data signal. ### Claim 16 A matrix type display apparatus, comprising: pixel electrodes arranged in a matrix; data signal lines and scanning signal lines for driving the pixel electrodes; and a data signal line driving circuit including sampling switches for sequentially sampling image data over one horizontal scanning period, each of the sampling switches being connected to the corresponding data signal line for outputting sampled data to the data signal line as a data signal, sampling capacitors for keeping sampled data, and precharge sampling means for effecting precharge sampling by turning on the sampling switches for applying a predetermined voltage to the data signal lines after the completion of the last horizontal scanning period and before the start of the proper sampling period for the respective sampling switches, the predetermined voltage for a corresponding data signal line having a polarity that is the same as a polarity of the sampled data output to the corresponding data signal line, even if the polarity of the sampled data is inverted. ### Claim 17 (depends on 16) A matrix type display apparatus according to claim 16, wherein the potential for the precharging has an intermediate value between extreme values of the potential of the data signal. ### Claim 18 A matrix type display apparatus, comprising: pixel electrodes arranged in a matrix; data signal lines and scanning signal lines for driving the pixel electrodes; and a data signal line driving circuit including sampling switches for sequentially sampling image data over one horizontal scanning period, each of the sampling switches being connected to a sampling capacitor for outputting sampled data obtained by the sampling to the sampling capacitor as a data signal, the sampling capacitor holding the sampled data, and precharge sampling means for effecting precharge sampling by turning on the sampling switches for applying a predetermined voltage to the sampling capacitors after the completion of the last horizontal scanning period and before the start of the proper sampling period for the respective sampling switches, the predetermined voltage applied to a corresponding sampling capacitor having a polarity that is the same as a polarity of the sampled data output to the corresponding sampling capacitor, even if the polarity of the sampled data is inverted. ### Claim 19 (depends on 18) A matrix type display apparatus according to claim 18, wherein the potential for the precharging has an intermediate value between extreme values of the potential of the data signal. ### Claim 20 A driving method for driving data signal lines of a matrix type display apparatus including pixel electrodes arranged in a matrix and data and scanning signal lines connected to the pixel electrodes, the driving method comprising the steps of: (a) sampling image data over one horizontal scanning period and storing the sampled image data in a plurality sampling capacitors; (b) precharging a plurality of holding capacitors with a predetermined voltage; (c) holding the sampled data in the plurality of holding capacitors subsequent to said step (b) of precharging, the sampled data being transferred from corresponding sampling capacitors upon termination of the one horizontal scanning period; and (d) outputting the sampled data from the holding capacitors to the data signal lines. ### Claim 21 A driving method for driving data signal lines of a matrix type display apparatus including pixel electrodes arranged in a matrix and data and scanning signal lines connected to the pixel electrodes, the driving method comprising the steps of: (a) sampling image data over one horizontal scanning period and storing the sampled image data in a plurality of sampling capacitors; (b) precharging a plurality of holding capacitors with a predetermined voltage; (c) holding the sampled data in the plurality of holding capacitors subsequent to said step (b) of precharging, the sampled data being transferred from corresponding sampling capacitors during the one horizontal scanning period; and (d) outputting the sampled data from the holding capacitors to the data signal lines. ### Claim 22 A driving method for driving data signal lines of a matrix type display apparatus including pixel electrodes arranged in a matrix and data and scanning signal lines connected to the pixel electrodes, the driving method comprising the steps of: (a) sampling image data over one horizontal scanning period and storing the sampled image data in a plurality of sampling capacitors corresponding to each data signal line; (b) precharging the plurality of data signal lines with a predetermined voltage; and (c) outputting the sampled data from the sampling capacitors to the data signal lines, subsequent to said step (b) of precharging, the predetermined voltage of a corresponding data signal line of said step (b) having a polarity that is the same as a polarity of the image data applied to the corresponding data signal line, even if the plurality of the image data is inverted. ### Claim 23 A driving method for driving data signal lines of a matrix type display apparatus including pixel electrodes arranged in a matrix and data and scanning signal lines connected to the pixel electrodes, the drive method comprising the steps of: (a) holding image data in a plurality of holding capacitors; (b) precharging the plurality of pixel electrodes with a predetermined voltage; and (c) turning on each of a plurality of pixel switches subsequent to said step (b) of precharging to enable supply of current from a corresponding data signal line to each corresponding pixel electrode, one pixel switch corresponding to each pixel electrode, the predetermined voltage of a corresponding pixel electrode of said step (b) having a polarity that is the same as a polarity of the image data applied to the corresponding data signal line, even if the polarity of the image data is inverted. ### Claim 24 A method of driving a matrix type display apparatus including a plurality of scanning signal lines and a plurality of data signal lines comprising: scanning each of the plurality of scanning signal lines a plurality of times within one vertical synchronization period, wherein a first pulse signal is applied to an nth scanning signal line of the plurality of scanning signal lines for precharging the nth scanning signal line during a first scanning period when image data applied to the data signal lines has the same polarity as the first pulse signal, and a second pulse signal is subsequently applied to the nth scanning signal line for charging the nth scanning signal line during a second scanning period when the image data applied to the data signal lines has the same polarity as the second pulse signal.