# US 12,223,896 B2 · Display device and method of driving the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,223,896 B2 - Document ID: US12223896B2 - Status: Granted - Kind: B2 - Application number: 18/113,296 - Filed: 2023-02-23 - Published: 2023-09-28 - Granted: 2025-02-11 - Earliest claimed: 2022-03-28 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Subin Park; Soyoung Kim; Jungkook Park - Web page: https://patentgrep.com/patent/US12223896B2 ## CPC - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 3/3291: in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements - G09G 2300/0465: Improved aperture ratio, e.g. by size reduction of the pixel circuit, e.g. for improving the pixel density or the maximum displayable luminance or brightness - 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 2300/0852: being a dynamic memory with more than 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 2310/08: Details of timing specific for flat panels, other than clock recovery - G09G 2320/0233: Improving the luminance or brightness uniformity across the screen - G09G 2320/043: Preventing or counteracting the effects of ageing - G09G 2320/045: Compensation of drifts in the characteristics of light emitting or modulating elements - 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 includes a display panel including pixels, and a timing controller which determines a first dimming period and a second dimming period based on a maximum luminance, determines an emission off ratio of the pixels as a first off ratio increasing discretely as the maximum luminance decreases in the first dimming period, and determines the emission off ratio as a second off ratio in the second dimming period. ## Claims ### Claim 1 A display device comprising: a display panel including pixels; and a timing controller which determines a first dimming period and a second dimming period based on a maximum luminance, determines an emission off ratio of the pixels as a first off ratio increasing discretely as the maximum luminance decreases in the first dimming period, and to determine the emission off ratio as a second off ratio in the second dimming period, wherein the emission off ratio increases discretely to a plurality of different levels at a plurality of discretely increasing points while the maximum luminance remains the same between contiguous discretely increasing points of the plurality of discretely increasing points during the first dimming period. ### Claim 2 (depends on 1) The display device of claim 1, wherein the maximum luminance of the first dimming period is less than the maximum luminance of the second dimming period. ### Claim 3 (depends on 2) The display device of claim 2, wherein the first off ratio is greater than or equal to the second off ratio. ### Claim 4 (depends on 2) The display device of claim 2, wherein the second off ratio has a fixed value. ### Claim 5 (depends on 1) The display device of claim 1, wherein the timing controller determines the emission off ratio as the first off ratio in a first period of the first dimming period, and determines the emission off ratio as a linear off ratio increasing linearly as the maximum luminance decreases in a second period of the first dimming period. ### Claim 6 (depends on 5) The display device of claim 5, wherein the maximum luminance of the first period is less than the maximum luminance of the second period. ### Claim 7 (depends on 6) The display device of claim 6, wherein the linear off ratio is less than or equal to the first off ratio and greater than or equal to the second off ratio. ### Claim 8 (depends on 1) The display device of claim 1, wherein the first off ratio increases linearly as the maximum luminance decreases except for the discretely increasing point. ### Claim 9 (depends on 1) The display device of claim 1, wherein each of the pixels comprises: a light emitting element; a driving transistor which generates a driving current; a first emission transistor which applies a first power voltage to the driving transistor in response to an emission signal; a second emission transistor which applies the driving current to the light emitting element in response to the emission signal; a first initialization transistor which applies a first initialization voltage to an anode electrode of the light emitting element in response to the emission signal; a data write transistor which applies a data voltage to the driving transistor in response to a write gate signal; a compensation transistor which connects a first electrode of the driving transistor and a control electrode of the driving transistor to each other in response to a compensation gate signal; a second initialization transistor which applies a second initialization voltage to the control electrode of the driving transistor in response to an initialization gate signal; a storage capacitor including a first electrode connected to the control electrode of the driving transistor and a second electrode which receives the first power voltage; and a boost capacitor including a first electrode which receives the write gate signal and a second electrode connected to the control electrode of the driving transistor. ### Claim 10 (depends on 9) The display device of claim 9, wherein an off duty ratio of the emission signal is determined as the emission off ratio. ### Claim 11 (depends on 1) The display device of claim 1, wherein the timing controller determines a third dimming period based on the maximum luminance, and determines the emission off ratio as a third off ratio in the third dimming period. ### Claim 12 (depends on 11) The display device of claim 11, wherein the maximum luminance of the third dimming period is less than the maximum luminance of the first dimming period. ### Claim 13 (depends on 12) The display device of claim 12, wherein the third off ratio is greater than or equal to the first off ratio. ### Claim 14 (depends on 11) The display device of claim 11, wherein the third off ratio has a fixed value. ### Claim 15 A method of driving a display device, the method comprising: determining a first dimming period, a second dimming period, and a third dimming period based on a maximum luminance; determining an emission off ratio of pixels as a first off ratio increasing discretely as the maximum luminance decreases in the first dimming period; determining the emission off ratio as a second off ratio in the second dimming period; and determining the emission off ratio as a third off ratio in the third dimming period, wherein the emission off ratio increases discretely to a plurality of different levels at a plurality of discretely increasing points during the first dimming period while the maximum luminance remains the same between contiguous discretely increasing points of the plurality of discretely increasing points. ### Claim 16 (depends on 15) The method of claim 15, wherein the maximum luminance of the first dimming period is less than the maximum luminance of the second dimming period, and wherein the maximum luminance of the third dimming period is less than the maximum luminance of the first dimming period. ### Claim 17 (depends on 16) The method of claim 16, wherein the first off ratio is greater than or equal to the second off ratio, and wherein the third off ratio is greater than or equal to the first off ratio. ### Claim 18 (depends on 15) The method of claim 15, wherein determining the emission off ratio in the first dimming period comprises: determining the emission off ratio as the first off ratio in a first period of the first dimming period; and determining the emission off ratio as a linear off ratio increasing linearly as the maximum luminance decreases in a second period of the first dimming period. ### Claim 19 (depends on 18) The method of claim 18, wherein the maximum luminance of the first period is less than the maximum luminance of the second period. ### Claim 20 (depends on 19) The method of claim 19, wherein the linear off ratio is less than or equal to the first off ratio and greater than or equal to the second off ratio.