# US 10,120,235 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 10,120,235 B2 - Document ID: US10120235B2 - Status: Granted - Kind: B2 - Application number: 15/315,801 - Filed: 2014-06-02 - Published: 2017-03-30 - Granted: 2018-11-06 - Earliest claimed: 2014-06-02 - Assignees: EIZO Corporation - Applicants: EIZO Corporation - Inventors: Keita Asahi; Mitsuhiro Takabatake; Takashi Murata - Web page: https://patentgrep.com/patent/US10120235B2 ## CPC - G02F 1/1336: {Illuminating devices} - G09G 3/342: {using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines} - G09G 3/36: using liquid crystals - G09G 2310/0237: Switching ON and OFF the backlight within one frame - G09G 2310/024: Scrolling of light from the illumination source over the display in combination with the scanning of the display screen - G09G 2310/08: Details of timing specific for flat panels, other than clock recovery - G09G 2320/0247: Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes - G09G 2320/064: by time modulation of the brightness of the illumination source - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS - 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 Provided is a liquid crystal display device that can further reduce flicker. The liquid crystal display device includes a control unit that controls the luminance of a backlight using PWM dimming. The backlight includes n (n≥4) number of backlight blocks that are turned on at different timings, and the n number of backlight blocks are turned on in an order different from the order in which the backlight blocks are physically arranged. ## Claims ### Claim 1 A liquid crystal display device comprising: a control unit configured to control luminance of a backlight using PWM dimming, wherein the backlight comprises n number of backlight blocks configured to be turned on at different timings, n being equal to or greater than 4; a duty ratio of the backlight is less than 25%; and the n number of backlight blocks are turned on in an order different from the order in which the backlight blocks are physically arranged and in an order in which backlight blocks at both edges are not turned on consecutively. ### Claim 2 (depends on 1) The liquid crystal display device of claim 1, wherein the n number of backlight blocks are turned on in an order such that adjacent backlight blocks other than the backlight blocks at both edges are not turned on consecutively. ### Claim 3 (depends on 2) The liquid crystal display device of claim 2, wherein n is equal to or greater than 5, and the n number of backlight blocks are turned on in an order such that adjacent backlight blocks are not turned on consecutively. ### Claim 4 (depends on 3) The liquid crystal display device of claim 3, wherein the n number of backlight blocks comprises blocks A, B, C, D, and E which are arranged in this order, and the blocks A, B, C, D, and E are turned on in the order of A ->C ->E ->B ->D, A ->D ->B ->E ->C, A ->B ->D ->E ->C, or A ->C ->E ->D ->B. ### Claim 5 (depends on 3) The liquid crystal display device of claim 3, wherein the control unit controls the luminance of the backlight using only DC dimming in a high-luminance region and controls the luminance of the backlight using a combination of DC dimming and PWM dimming in a low-luminance region for which a lower luminance setting than a luminance setting for the high-luminance region is set. ### Claim 6 (depends on 2) The liquid crystal display device of claim 2, wherein the n number of backlight blocks comprises blocks A, B, C, and D which are arranged in this order, and the blocks A, B, C, and D are turned on in the order of A ->B ->D ->C or A ->C ->D ->B. ### Claim 7 (depends on 2) The liquid crystal display device of claim 2, wherein the n number of backlight blocks comprises blocks A, B, C, D, and E which are arranged in this order, and the blocks A, B, C, D, and E are turned on in the order of A ->C ->E ->B ->D, A ->D ->B ->E ->C, A ->B ->D ->E ->C, or A ->C ->E ->D ->B. ### Claim 8 (depends on 2) The liquid crystal display device of claim 2, wherein the control unit controls the luminance of the backlight using only DC dimming in a high-luminance region and controls the luminance of the backlight using a combination of DC dimming and PWM dimming in a low-luminance region for which a lower luminance setting than a luminance setting for the high-luminance region is set. ### Claim 9 (depends on 1) The liquid crystal display device of claim 1, wherein the n number of backlight blocks comprises blocks A, B, C, and D which are arranged in this order, and the blocks A, B, C, and D are turned on in the order of A ->B ->D ->C or A ->C ->D ->B. ### Claim 10 (depends on 9) The liquid crystal display device of claim 9, wherein the control unit controls the luminance of the backlight using only DC dimming in a high-luminance region and controls the luminance of the backlight using a combination of DC dimming and PWM dimming in a low-luminance region for which a lower luminance setting than a luminance setting for the high-luminance region is set. ### Claim 11 (depends on 1) The liquid crystal display device of claim 1, wherein the n number of backlight blocks comprises blocks A, B, C, D, and E which are arranged in this order, and the blocks A, B, C, D, and E are turned on in the order of A ->C ->E ->B ->D, A ->D ->B ->E ->C, A ->B ->D ->E ->C, or A ->C ->E ->D ->B. ### Claim 12 (depends on 11) The liquid crystal display device of claim 11, wherein the control unit controls the luminance of the backlight using only DC dimming in a high-luminance region and controls the luminance of the backlight using a combination of DC dimming and PWM dimming in a low-luminance region for which a lower luminance setting than a luminance setting for the high-luminance region is set. ### Claim 13 (depends on 1) The liquid crystal display device of claim 1, wherein the control unit controls the luminance of the backlight using only DC dimming in a high-luminance region and controls the luminance of the backlight using a combination of DC dimming and PWM dimming in a low-luminance region for which a lower luminance setting than a luminance setting for the high-luminance region is set.