# US 11,443,678 B2 · Display device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,443,678 B2 - Document ID: US11443678B2 - Status: Granted - Kind: B2 - Application number: 16/808,906 - Filed: 2020-03-04 - Published: 2020-11-12 - Granted: 2022-09-13 - Earliest claimed: 2019-05-10 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Jong Won Park; Chae Han Hyun - Web page: https://patentgrep.com/patent/US11443678B2 ## CPC - G09G 3/2003: {Display of colours (specific for liquid crystal displays G09G3/3607)} - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 3/3266: Details of drivers for scan electrodes - G09G 2300/0819: used for counteracting undesired variations, e.g. feedback or autozeroing - G09G 2300/0842: forming a memory circuit, e.g. a dynamic memory with one capacitor - G09G 2300/0861: with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes - G09G 2300/0866: by means of changes in the pixel supply voltage - G09G 2310/0267: Details of drivers for scan electrodes, other than drivers for liquid crystal, plasma or OLED displays - 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 2310/08: Details of timing specific for flat panels, other than clock recovery - 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 Systems and methods are provided for a display device that includes a display unit. The display unit includes scan lines and pixels coupled to the scan lines. A timing controller operates in a first mode and a second mode and generates a start signal, based on a vertical synchronization signal provided from the outside. A scan driver generates a scan signal, based on the start signal, and sequentially provides the scan signal to the scan lines. The timing controller generates the start signal immediately after a pulse of the vertical synchronization signal is applied in the first mode, and generates the start signal before a pulse the vertical synchronization signal is applied in the second mode. ## Claims ### Claim 1 A display device comprising: a display unit including scan lines and pixels coupled to the scan lines; a timing controller configured to operate in a first mode and a second mode, and to generate a start signal based on a vertical synchronization signal; and a scan driver configured to generate a scan signal based on the start signal, and sequentially provide the scan signal to the scan lines, wherein the timing controller generates the start signal immediately after a pulse of the vertical synchronization signal is applied in the first mode, and generates the start signal before the pulse of the vertical synchronization signal is applied in the second mode. ### Claim 2 (depends on 1) The display device of claim 1, wherein a first frame period before the display device is switched from the first mode to the second mode includes two start signals, and the pulse of the vertical synchronization signal represents a start of a frame period. ### Claim 3 (depends on 2) The display device of claim 2, wherein, in the first frame period, the start signal has a second pulse immediately after the scan signal generated based on a first pulse of the start signal is provided to the scan lines. ### Claim 4 (depends on 2) The display device of claim 2, wherein a width of a second frame period in the second mode is smaller than that of the first frame period in the first mode. ### Claim 5 (depends on 4) The display device of claim 4, wherein the timing controller generates the start signal, based on a horizontal synchronization signal provided from the outside, wherein a period of the horizontal synchronization signal in the second mode is smaller than that of the horizontal synchronization signal in the first mode. ### Claim 6 (depends on 5) The display device of claim 5, wherein, in the second mode, a time interval from a time at which the start signal is generated to a time at which the pulse of the vertical synchronization signal is applied is equal to or smaller than three times of the period of the horizontal synchronization signal. ### Claim 7 (depends on 5) The display device of claim 5, wherein a number of pulses of the horizontal synchronization signal, which are included in the second frame period, is equal to that of pulses of the horizontal synchronization signal, which are included in the first frame period. ### Claim 8 (depends on 7) The display device of claim 7, wherein the timing controller includes: a counter configured to output a counting value by counting a number of pulses of the horizontal synchronization signal, with respect to the vertical synchronization signal; and a start signal generator configured to generate the start signal by comparing the counting value with a predetermined value. ### Claim 9 (depends on 8) The display device of claim 8, wherein the counter counts a number of pulses of the horizontal synchronization signal in the first mode, and reverse-counts a number of pulses of the horizontal synchronization signal from a reference value in the second mode. ### Claim 10 (depends on 1) The display device of claim 1, wherein the start signal has a second pulse, while the scan signal generated based on a first pulse of the start signal is being provided to the scan lines in the second mode. ### Claim 11 (depends on 10) The display device of claim 10, wherein the scan signal is simultaneously provided to at least two of the scan lines in the second mode. ### Claim 12 (depends on 11) The display device of claim 11, wherein the display unit includes a first display area, a second display area, and a third display area, which are divided by some of the scan lines, wherein the first display area and the third display area display a color image in the first mode, and display a single color image in the second mode, wherein the start signal has the second pulse at a time at which the scan signal is provided to a second scan line corresponding to the second display area among the scan lines. ### Claim 13 (depends on 12) The display device of claim 12, wherein, in the second mode, the scan signal is simultaneously provided to a first scan line corresponding to the first display area and a third scan line corresponding to the third display area among the scan lines. ### Claim 14 (depends on 13) The display device of claim 13, further comprising a data driver configured to generate a data signal, wherein the display unit further includes data lines, wherein the pixels are coupled to the data lines, wherein the data driver provides the data lines with black data corresponding to a black color, while the scan signal is being provided to the first scan line corresponding to the first display area among the scan lines in the second mode. ### Claim 15 A display device comprising: a display unit including a plurality of scan lines and a pixel coupled to the scan lines; a timing controller configured to operate in a first mode and a second mode, and to generate a start signal based on a vertical synchronization signal; and a scan driver configured to generate a scan signal based on the start signal, and sequentially provide the scan signal to the scan lines, wherein the timing controller generates the start signal immediately after a pulse of the vertical synchronization signal is applied in the first mode, and generates the start signal at a time at which a pulse of the vertical synchronization signal is applied in the second mode. ### Claim 16 (depends on 15) The display device of claim 15, wherein the display unit includes a first display area, a second display area, and a third display area, which are divided by some of the scan lines, wherein the first display area and the third display area display a color image in the first mode, and display a single color image in the second mode, wherein a number of first scan lines corresponding to the second display area among the scan lines is greater than that of second scan lines corresponding to the third display area among the scan lines. ### Claim 17 A method of controlling a display device comprising: selecting a first display mode; transmitting a first vertical synchronization signal to a pixel; transmitting a first start signal to the pixel after the first vertical synchronization signal based on the first display mode; selecting a second display mode; transmitting a second vertical synchronization signal to the pixel; and transmitting a second start signal to the pixel simultaneously to or before the second vertical synchronization signal based on the second display mode. ### Claim 18 (depends on 17) The method of claim 17, wherein the first display mode comprises a normal display mode and the second display mode comprises a low persistence mode (LPM). ### Claim 19 (depends on 18) The method of claim 18, wherein the second vertical synchronization signal is preceded by a vertical front porch (VFP) period and followed by a vertical back porch (VBP) period based on the second display mode. ### Claim 20 (depends on 17) The method of claim 17, wherein the first vertical synchronization signal and the first start signal are transmitted during a first horizontal synchronization period, and the second vertical synchronization signal and the second start signal are transmitted during a second horizontal synchronization period. ### Claim 21 (depends on 1) The display device of claim 1, wherein a timing at which the start signal is generated in the second mode with respect to pulses of the vertical synchronization signal is different from a timing at which the start signal is generated in the first mode with respect to the pulses of the vertical synchronization signal, and wherein a pulse width of the start signal in the second mode is equal to a pulse width of the start signal in the first mode. ### Claim 22 (depends on 15) The display device of claim 15, wherein a timing at which the start signal is generated in the second mode with respect to pulses of the vertical synchronization signal is different from a timing at which the start signal is generated in the first mode with respect to the pulses of the vertical synchronization signal, and wherein a pulse width of the start signal in the second mode is equal to a pulse width of the start signal in the first mode. ### Claim 23 (depends on 17) The method of claim 17, wherein a timing at which the second start signal is transmitted in the second display mode with respect to pulses of the second vertical synchronization signal is different from a timing at which the first start signal is transmitted in the first display mode with respect to pulses of the first vertical synchronization signal, and wherein a pulse width of the second start signal in the second display mode is equal to a pulse width of the first start signal in the first display mode.