# US 8,786,644 B2 · Control device, display apparatus, and electronic apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,644 B2 - Document ID: US8786644B2 - Status: Granted - Kind: B2 - Application number: 13/422,308 - Filed: 2012-03-16 - Published: 2012-09-27 - Granted: 2014-07-22 - Earliest claimed: 2011-03-22 - Assignees: Seiko Epson Corporation - Applicants: Kota Muto; Yusuke Yamada - Inventors: Kota Muto; Yusuke Yamada - Web page: https://patentgrep.com/patent/US8786644B2 ## CPC - G09B 5/02: with visual presentation of the material to be studied, e.g. using film strip - G09B 5/062: {Combinations of audio and printed presentations, e.g. magnetically striped cards, talking books, magnetic tapes with printed texts thereon} - G09G 3/2044: {using dithering} - G09G 3/344: {based on particles moving in a fluid or in a gas, e.g. electrophoretic devices (electrophoretic devices per se G02F1/167)} - G09B: EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS (devices for psychotechnics or for testing reaction times A61B5/16; games, sports, amusements A63; projectors, projector screens G03B) - 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 control device includes output means for outputting a signal for controlling an electro-optical device having a plurality of pixels which are provided so as to correspond to intersections of a plurality of scanning lines and a plurality of data lines, to the electro-optical device, and control means for controlling the output means to output a signal for applying a voltage corresponding to data stored in a memory to the plurality of data lines, whereby an image which is written by the signal when a first condition is satisfied has a higher spatial frequency of grayscale variations in an extending direction of the data lines than that of an image which is written by the signal when a second condition is satisfied. ## Claims ### Claim 1 A control device comprising: an output unit configured to output a signal for controlling an electro-optical device having a plurality of pixels which are provided so as to correspond to intersections of a plurality of scanning lines and a plurality of data lines, to the electro-optical device; a control unit configured to control the output unit to output a signal for applying a voltage corresponding to data stored in a memory to the plurality of data lines, and a color quantization process unit configured to perform a color quantization process for a grayscale value of each of the plurality of pixels, indicated by data stored in the memory, wherein a first image which has a first spatial frequency of grayscale variations in an extending direction of the data lines is written by the signal when a first condition is satisfied, and a second image which has a second spatial frequency of grayscale variations in the extending direction of the data lines is written by the signal when a second condition is satisfied, the first spatial frequency is higher than the second spatial frequency, and the color quantization process unit is configured to perform the color quantization process so that the first image which is obtained through the color quantization process when the first condition is satisfied has the first spatial frequency and the second image which is obtained through the color quantization process when the second condition is satisfied has the second spatial frequency. ### Claim 2 (depends on 1) The control device according to claim 1, further comprising a first storage unit configured to store a first dither matrix and a second dither matrix which has a lower spatial frequency of grayscale variations in the extending direction of the data lines than that of the first dither matrix, wherein the color quantization process unit performs the color quantization process using the first dither matrix when the first condition is satisfied and using the second dither matrix when the second condition is satisfied. ### Claim 3 (depends on 1) The control device according to claim 1, wherein the second condition is a condition that an updating frequency of the image is equal to or more than a threshold value. ### Claim 4 (depends on 3) The control device according to claim 3, wherein the first condition is a condition that the updating frequency of the image is less than the threshold value. ### Claim 5 (depends on 4) The control device according to claim 4, wherein the first condition is a condition that updating of the image is finished at a frequency which is equal to or more than the threshold value. ### Claim 6 (depends on 1) The control device according to claim 1, wherein the second condition is a condition that a remaining capacity of a battery which supplies power to the control device is less than a threshold value. ### Claim 7 (depends on 6) The control device according to claim 6, wherein the first condition is a condition that the remaining capacity of the battery is equal to or more than the threshold value. ### Claim 8 (depends on 1) The control device according to claim 1, wherein the second condition is a condition that the image is a character image. ### Claim 9 (depends on 8) The control device according to claim 8, wherein the first condition is a condition that the image is a picture image. ### Claim 10 (depends on 1) A display apparatus comprising: the control device according to claim 1; and the electro-optical device. ### Claim 11 (depends on 10) An electronic apparatus comprising the display apparatus according to claim 10. ### Claim 12 A control device comprising: an output unit configured to output a signal for controlling an electro-optical device having a plurality of pixels which are provided so as to correspond to intersections of a plurality of scanning lines and a plurality of data lines, to the electro-optical device; and a control unit configured to control the output unit to output a signal for applying a voltage corresponding to data stored in a memory to the plurality of data lines, wherein a first image which has a first spatial frequency of grayscale variations in an extending direction of the data lines is written by the signal when a first condition is satisfied, and a second image which has a second spatial frequency of grayscale variations in the extending direction of the data lines is written by the signal when a second condition is satisfied, the first spatial frequency being higher than the second spatial frequency, wherein grayscales of the plurality of pixels are changed by a writing operation where a voltage is applied to a corresponding pixel multiple times, wherein the control unit determines a pixel of which a grayscale is to be changed of the plurality of pixels, using a comparison result between image data read from a second storage unit configured to store the image data indicating an image which is newly displayed on the electro-optical device, and scheduled image data read from a third storage unit configured to store the scheduled image data indicating an image which is scheduled to be displayed on the electro-optical device by the writing operation in progress, wherein the control unit controls the output unit to output the signal for starting the writing operation for a corresponding pixel so as to have a grayscale set by the image data if the pixel determined as a pixel of which a grayscale is to be changed is not in the writing operation, and controls the output unit to output the signal for starting the writing operation for a corresponding pixel so as to have a grayscale set by the image data after the writing operation in progress is finished if the pixel determined as the pixel of which a grayscale is to be changed is in the writing operation, and wherein the second condition is a condition that there is a pixel where the writing operation is in progress. ### Claim 13 (depends on 12) The control device according to claim 12, wherein the first condition is a condition that there is no pixel where the writing operation is in progress. ### Claim 14 (depends on 13) The control device according to claim 13, wherein, when the first condition is satisfied, the control unit rewrites an image which has been written according to the second condition, according to the first condition. ### Claim 15 A control device comprising: an output unit configured to output a signal for controlling an electro-optical device having a plurality of pixels which are provided so as to correspond to intersections of a plurality of scanning lines and a plurality of data lines, to the electro-optical device; and a control unit configured to control the output unit to output a signal for applying a voltage corresponding to data stored in a memory to the plurality of data lines, an image processing unit which processes an original image to a first image at a first operation mode and to a second image at a second operation mode, a number of gray level of the second image is same as a number of gray level of the first image, wherein a frequency of electrical change of the data line when rewriting the second image is less than a frequency of electrical change of the data line when rewriting in the first image. ### Claim 16 A control device comprising: an output unit configured to output a signal for controlling an electro-optical device having a plurality of pixels which are provided so as to correspond to intersections of a plurality of scanning lines and a plurality of data lines, to the electro-optical device; and a control unit configured to control the output unit to output a signal for applying a voltage corresponding to data stored in a memory to the plurality of data lines, an image processing unit which processes an original image to a first image at a first operation mode and to a second image at a second operation mode, a number of gray level of the second image is same as a number of gray level of the first image, wherein a frequency of grayscale variation corresponding to pixel data of a first gray level and pixel data of a second gray level in the first image in an extending direction of the plurality of data lines is larger than frequency of grayscale variation corresponding to pixel data of the first gray level and pixel data of the second gray scale level in the second image in an extending direction of the plurality of data lines.