# US 7,184,098 B2 · Cyclic data signal averaging system and method for use in video display systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,184,098 B2 - Document ID: US7184098B2 - Status: Granted - Kind: B2 - Application number: 10/782,045 - Filed: 2004-02-19 - Published: 2005-08-25 - Granted: 2007-02-27 - Earliest claimed: 2004-02-19 - Assignees: Spatialight, Inc. - Inventors: Charles D. Pencil; Michael S. Jin - Web page: https://patentgrep.com/patent/US7184098B2 ## CPC - G09G 3/20: for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix {no fixed position being assigned to or needed to be assigned to the individual characters or partial characters} - G09G 3/3685: {Details of drivers for data electrodes} - G09G 2310/027: Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters - G09G 2310/0275: Details of drivers for data electrodes, other than drivers for liquid crystal, plasma or OLED displays, not related to handling digital grey scale data or to communication of data to the pixels by means of a current - G09G 2310/0297: Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns - G09G 2320/0233: Improving the luminance or brightness uniformity across the screen - G09G 2352/00: Parallel handling of streams of display data - 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 system and method for reducing periodic intensity variation in a video image includes applying input signals representing video image data to multiple circuit components by sequentially shifting the input signals through the circuit components to produce output signals that match corresponding input signals. Matching the output signals to the input signals overcomes the effect of inherent differences in characteristics of analog circuit components. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims. ## Claims ### Claim 1 A method of reducing periodic intensity variation in a video image, comprising: rotating a plurality of input signals to a video display circuit so that each input signal in the plurality of input signals is repeatedly sequentially shifted; converting each input signal from digital to analog and amplifying each signal; and separating each amplified signal to produce a plurality of output signals, each output signal in the plurality of output signals having an amplitude matching a corresponding input signal. ### Claim 2 (depends on 1) The method of claim 1, further comprising applying each sequentially shifted input signal to a different analog circuit in a plurality of analog circuits. ### Claim 3 (depends on 2) The method of claim 2, wherein each analog circuit includes a digital-to-analog converter and an operational amplifier. ### Claim 4 (depends on 3) The method of claim 3, wherein the rotating a plurality of input signals includes multiplexing the plurality of input signals. ### Claim 5 (depends on 4) The method of claim 4, wherein the rotating a plurality of input signals includes applying the plurality of input signals to a digital cross-point switch. ### Claim 6 (depends on 3) The method of claim 3, wherein the separating each amplified signal to produce a plurality of output signals includes demultiplexing the plurality of output signals. ### Claim 7 (depends on 6) The method of claim 6, wherein the separating each amplified signal to produce a plurality of output signals includes applying the plurality of output signals to an analog cross-point switch. ### Claim 8 (depends on 1) The method of claim 1, wherein each signal in the plurality of input signals represents a column of video image data. ### Claim 9 (depends on 3) The method of claim 3, wherein each output signal has an amplitude that substantially matches an amplitude of a corresponding input signal, producing time-averaged signals without having to tune each operational amplifier in the plurality of analog circuits to compensate for the effect of differences in the operational amplifiers. ### Claim 10 An apparatus for reducing periodic intensity variation in a video image, comprising: a plurality of input signals, each input signal in the plurality of input signals representing a column of video image data; a first cross-point switch receiving the plurality of input signals, the first cross-point switch repeatedly sequentially shifting each input signal through an analog circuit portion, the analog circuit portion including sets of components each having an digital to analog converter and an operational amplifier; and a second cross-point switch receiving the amplified output of the analog circuit portion, the second cross-point switch separating each amplified output to produce an output signal, such that each output signal has an amplitude that matches a corresponding input signal. ### Claim 11 (depends on 10) The apparatus of claim 10, further comprising a controller coupled to the first cross-point switch and producing an inverting input to the first cross-point switch, the inverting input causing the plurality of input signals to be sequentially shifted so that each input signal is repeatedly applied to a different set of components in the analog circuit portion. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the first cross-point switch is a digital cross-point switch. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the first cross-point switch is a multiplexer. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the second cross-point switch is an analog cross-point switch. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the analog cross-point switch is a demultiplexer. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein the plurality of input signals include four columns of input. ### Claim 17 An apparatus for reducing periodic intensity variation in a video image, comprising: means for rotating a plurality of input signals to a video display circuit so that each input signal in the plurality of input signals is repeatedly sequentially shifted; means for converting each input signal from digital to analog and amplifying each signal; and means for separating each amplified signal to produce a plurality of output signals, each output signal in the plurality of output signals having an amplitude that matches a corresponding input signal. ### Claim 18 (depends on 17) The apparatus of claim 17, further comprising means for applying each sequentially shifted input signal to a different analog circuit in a plurality of analog circuits. ### Claim 19 (depends on 18) The apparatus of claim 18, further comprising means for converting each sequentially shifted input signal from digital to analog. ### Claim 20 (depends on 19) The apparatus of claim 19, further comprising means for amplifying each sequentially shifted input signal. ### Claim 21 A method of reducing periodic intensity variation in a video image, comprising: providing a plurality of analog input signals to a video display system; rotating the plurality of analog input signals so that each input signal is repeatedly sequentially shifted to produce a plurality of output signals; and demultiplexing and amplifying the plurality of output signals, wherein each output signal in the plurality of output signals has an amplitude matching a corresponding input signal.