# US 12,190,784 B2 · Display device for reducing flicker and electronic device comprising same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,190,784 B2 - Document ID: US12190784B2 - Status: Granted - Kind: B2 - Application number: 17/983,049 - Filed: 2022-11-08 - Published: 2023-03-09 - Granted: 2025-01-07 - Earliest claimed: 2021-04-23 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Juseok Lee; Minwoo Lee; Seoyoung Lee - Web page: https://patentgrep.com/patent/US12190784B2 ## CPC - G09G 3/2096: {Details of the interface to the display terminal specific for a flat panel (suitable for both CRT and flat panel G09G5/006; specific for a CRT G09G1/167)} - G09G 2310/06: Details of flat display driving waveforms - 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 - G09G 2340/0435: Change or adaptation of the frame rate of the video stream - 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 display device including a display panel and a display driving circuit to control the display panel are provided. The display driving circuit includes a light emitting control driver to input a light emitting signal for controlling the brightness of the display panel into the display panel. When a light emitting control signal including a plurality of pulses is input into the light emitting control driver to control the light emitting signal, and when the operating frequency of the light emitting control signal is changed, pulse widths corresponding to at least two pulses of pulses included in the light emitting control signal may be adjusted to differ from each other in a frame after the target time point to change the operating frequency. ## Claims ### Claim 1 A display device comprising: a display panel; and a display driving circuit configured to control the display panel and including a light emitting control driver to input a light emitting signal for controlling a brightness of the display panel into the display panel, wherein the display driving circuit is further configured to: input a light emitting control signal including a plurality of pulses to the light emitting control driver, to control the light emitting signal, change an operating frequency of the light emitting control signal at a target time point from a first frequency in a first frame prior to the target time point to a second frequency in a second frame after the target time point, and adjust pulse widths, which correspond to at least two pulses of the plurality of pulses included in the light emitting control signal, to differ from each other, in the second frame subsequent to the first frame, when a duty-ratio difference between a specific duty ratio and a target duty ratio is equal to or greater than a reference value, and wherein the target duty ratio is calculated based on a last low level pulse among the plurality of pulses in the first frame and a first high level pulse right after the last low level pulse among the plurality of pulses in the second frame. ### Claim 2 (depends on 1) The display device of claim 1, wherein the display driving circuit is further configured to: arrange the at least two pulses, which has the adjusted pulse widths, such that the at least two pulses are not adjacent to each other. ### Claim 3 (depends on 1) The display device of claim 1, wherein the display driving circuit is further configured to: sequentially increase or decrease pulse widths corresponding to pulses included in the second frame after the target time point to change the operating frequency. ### Claim 4 (depends on 1) The display device of claim 1, wherein the display driving circuit is further configured to: adjust a pulse width of the first high level pulse right after the target time point, such that the duty-ratio difference is less than the reference value. ### Claim 5 A display device comprising: a display panel; and a display driving circuit configured to control the display panel and including a light emitting control driver to input a light emitting signal for controlling a brightness of the display panel into the display panel, wherein the display driving circuit is configured to: input a light emitting control signal including a plurality of pulses to the light emitting control driver, to control the light emitting signal, change an operating frequency from a first frequency in a first frame to a second frequency in a second frame after the first frame, and adjust pulse widths, which correspond to at least two pulses of pulses included in the light emitting control signal in the second frame subsequent to the first frame, to differ from each other, or insert a third frame between a first frame and the second frame, which are subsequent to each other, and adjust the pulse widths, which correspond to at least two pulses of pulses included in the light emitting control signal in the third frame, to differ from each other, when a duty-ratio difference between a specific duty ratio and a target duty ratio is equal to or greater than a reference value, and wherein the target duty ratio is calculated based on one low level pulse applied last among the plurality of pulses in the first frame and one high level pulse applied first among the plurality of pulses in the second frame. ### Claim 6 (depends on 5) The display device of claim 5, wherein the display driving circuit is further configured to: generate the light emitting control signal to have a third operating frequency between a first operating frequency of the first frame and a second operating frequency of the second frame, in the third frame, and adjust pulse widths corresponding to at least two pulses of pulses included in the third frame, such that the duty-ratio difference is less than the reference value. ### Claim 7 (depends on 6) The display device of claim 6, wherein the display driving circuit is further configured to: arrange the at least two pulses, which has the adjusted pulse widths, such that the at least two pulses are not adjacent to each other, in the third frame. ### Claim 8 (depends on 5) The display device of claim 5, wherein the display driving circuit is further configured to: sequentially increase or decrease pulse widths corresponding to the pulses included in the third frame. ### Claim 9 (depends on 8) The display device of claim 8, wherein the pulse widths corresponding to the pulses included in the third frame are set to values between a pulse width corresponding to a pulse included in the first frame and a pulse width corresponding to a pulse included in the second frame. ### Claim 10 (depends on 5) The display device of claim 5, wherein the display driving circuit is further configured to: generate the light emitting control signal to have a pulse cycle different from a pulse cycle in the first frame or a pulse cycle in the second frame, in the third frame. ### Claim 11 (depends on 5) The display device of claim 5, wherein the display driving circuit is further configured to: generate the light emitting control signal to have a pulse cycle greater than a pulse cycle in the first frame or a pulse cycle in the second frame, in the third frame. ### Claim 12 A display device comprising: a display panel; and a display driving circuit configured to control the display panel and including a light emitting control driver to input a light emitting signal for controlling a brightness of the display panel into the display panel, wherein the display driving circuit is configured to: input a light emitting control signal including a plurality of pulses to the light emitting control driver, to control the light emitting signal, change an operating frequency from a first frequency in a first frame to a second frequency in a second frame after the first frame, insert a bridge frame between the first frame and the second frame, which are subsequent to each other, and adjust pulse widths, which correspond to at least two pulses of pulses included in the light emitting control signal in the bridge frame, to differ from each other, when a duty-ratio difference between a specific duty ratio and a target duty ratio is equal to or greater than a first reference value, and wherein the target duty ratio is calculated based on a low level pulse applied last among the plurality of pulses in the first frame and a high level pulse applied first among the plurality of pulses in the second frame. ### Claim 13 (depends on 12) The display device of claim 12, wherein the display driving circuit is further configured to: adjust pulse widths, which correspond to at least two pulses of pulses included in the second frame, to differ from each other, when the duty-ratio difference is less than the first reference value and greater than or equal to a second reference value. ### Claim 14 (depends on 13) The display device of claim 13, wherein the display driving circuit is further configured to: adjust the pulse widths corresponding to the at least two pulses of the pulses included in the second frame, such that the duty-ratio difference is less than the second reference value. ### Claim 15 (depends on 14) The display device of claim 14, wherein the display driving circuit is further configured to: arrange the at least two pulses, which has the adjusted pulse widths, in the second frame, such that the at least two pulses are not adjacent to each other. ### Claim 16 (depends on 13) The display device of claim 13, wherein the display driving circuit is further configured to: sequentially increase or decrease pulse widths corresponding to the pulses included in the second frame. ### Claim 17 (depends on 12) The display device of claim 12, wherein the display driving circuit is further configured to: generate, in the bridge frame, the light emitting control signal to have a third operating frequency between a first operating frequency of the first frame and a second operating frequency of the second frame, and adjust the pulse widths corresponding to the at least two pulses of the pulses included in the bridge frame, such that the duty-ratio difference is less than the first reference value. ### Claim 18 (depends on 12) The display device of claim 12, wherein the display driving circuit is further configured to: sequentially increase or decrease pulse widths corresponding to the pulses included in the bridge frame. ### Claim 19 (depends on 18) The display device of claim 18, wherein the pulse widths corresponding to the pulses included in the bridge frame are set to values between a pulse width corresponding to a pulse included in the first frame and a pulse width corresponding to a pulse included in the second frame. ### Claim 20 (depends on 12) The display device of claim 12, wherein the display driving circuit is further configured to: generate the light emitting control signal to have a cycle different from a cycle in the first frame or a cycle in the second frame, in the bridge frame.