# US 2014/0198085 A1 · Pixel and organic light emitting display using the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0198085 A1 - Document ID: US20140198085A1 - Status: Published application - Kind: A1 - Application number: 14/148,667 - Filed: 2014-01-06 - Published: 2014-07-17 - Earliest claimed: 2013-01-17 - Assignees: Samsung Display Co., Ltd. - Applicants: Samsung Display Co., Ltd. - Inventors: Yong-Sung Park; Tak-Young Lee; Hai-Jung In; Bo-Yong Chung; Min-Hyuk Choi; Yong-Jae Kim - Web page: https://patentgrep.com/patent/US20140198085A1 ## CPC - G09G 3/3241: the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror - G09G 3/3233: with pixel circuitry controlling the current through the light-emitting element - G09G 2300/0819: used for counteracting undesired variations, e.g. feedback or autozeroing - 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 2310/0245: Clearing or presetting the whole screen independently of waveforms, e.g. on power-on (G09G2310/063 takes precedence) - G09G 2310/0251: Precharge or discharge of pixel before applying new pixel voltage - 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 2360/148: the light being detected by light detection means within each pixel - 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 pixel includes an organic light emitting diode, a first driver and a second driver. The second driver controls an amount of current supplied from a first power source to the organic light emitting diode, corresponding to a previous data signal. The first driver stores a current data signal supplied from a data line and supplies the previous data signal to the second driver. In the pixel, the second driver includes a sixth transistor coupled between an initialization power source and a first node coupled to a gate electrode of a first transistor, the sixth transistor being configured to turn on when a first control signal is supplied; and a seventh transistor coupled between the first power source and a second node commonly coupled to the first and second drivers, the seventh transistor being configured to turn on when the first control signal is supplied. ## Claims ### Claim 1 A pixel comprising: an organic light emitting diode; a second driver configured to control an amount of current supplied from a first power source to the organic light emitting diode, corresponding to a previous data signal; and a first driver configured to store a current data signal supplied from a data line and to supply the previous data signal to the second driver, wherein the second driver comprises: a sixth transistor coupled between an initialization power source and a first node coupled to a gate electrode of a first transistor, the sixth transistor being configured to turn on when a first control signal is supplied; and a seventh transistor coupled between the first power source and a second node commonly coupled to the first and second drivers, the seventh transistor being configured to turn on when the first control signal is supplied. ### Claim 2 (depends on 1) The pixel of claim 1, wherein the initialization power source has a voltage lower than that of a data signal supplied to the data line. ### Claim 3 (depends on 1) The pixel of claim 1, wherein the first driver comprises: a second transistor coupled between the data line and a third node, the second transistor being configured to turn on when a scan signal is supplied to a scan line; a third transistor coupled between the third and second nodes, the third transistor being configured to turn on when a second control signal is supplied; and a second capacitor coupled between the third node and the initialization power source. ### Claim 4 (depends on 3) The pixel of claim 3, wherein the third and sixth transistors have turn-on periods not overlapped with each other. ### Claim 5 (depends on 3) The pixel of claim 3, wherein the second transistor has a turn-on period not overlapped with those of the third and sixth transistors. ### Claim 6 (depends on 1) The pixel of claim 1, wherein the second driver comprises: an eighth transistor coupled between the first power source and the second node, the second node being coupled to a first electrode of the first transistor, the eighth transistor being configured to turn off when an emission control signal is supplied and to turn on otherwise; a fifth transistor coupled between the first node and a second electrode of the first transistor, the fifth transistor being configured to turn on when a second control signal is supplied; a ninth transistor coupled between the second electrode of the first transistor and an anode electrode of the organic light emitting diode, the ninth transistor being configured to turn off when the emission control signal is supplied and to turn on otherwise; and a first capacitor coupled between the first node and the first power source. ### Claim 7 (depends on 6) The pixel of claim 6, wherein the eighth transistor has a turn-on period not overlapped with those of the fifth and sixth transistors. ### Claim 8 (depends on 6) The pixel of claim 6, wherein the fifth and sixth transistors have turn-on periods not overlapped with each other. ### Claim 9 (depends on 6) The pixel of claim 6, wherein the second driver further comprises a fourth transistor coupled between the anode electrode of the organic light emitting diode and the initialization power source, the fourth transistor being configured to turn on when the first control signal is supplied. ### Claim 10 (depends on 6) The pixel of claim 6, wherein the second driver further comprises a fourth transistor coupled between the anode electrode of the organic light emitting diode and the initialization power source, the fourth transistor being configured to turn on when the second control signal is supplied. ### Claim 11 (depends on 6) The pixel of claim 6, wherein the second driver further comprises a fourth transistor coupled between the anode electrode of the organic light emitting diode and a second control line to which the second control signal is supplied, the fourth transistor having a gate electrode coupled to the second control line. ### Claim 12 (depends on 6) The pixel of claim 6, wherein the second driver further comprises a photodiode coupled in parallel to the first capacitor between the first node and the first power source. ### Claim 13 (depends on 12) The pixel of claim 12, wherein the photodiode is configured to control an increment of a voltage at the first node, corresponding to a luminance of the organic light emitting diode. ### Claim 14 (depends on 12) The pixel of claim 12, wherein the photodiode is configured to control an increment of a voltage at the first node, in proportion to a luminance of the organic light emitting diode. ### Claim 15 (depends on 6) The pixel of claim 6, wherein the second driver further comprises a third capacitor coupled between the anode electrode of the organic light emitting diode and the second node. ### Claim 16 An organic light emitting display comprising: a control driver configured to supply a first control signal to a first control line, and to supply a second control signal to a second control line during a first period in one frame; a scan driver configured to supply an emission control signal to an emission control line during the first period, a second period, and a third period in the one frame, and to progressively supply a scan signal to scan lines during a fourth period in the one frame; a data driver configured to supply a data signal to data lines, in synchronization with the scan signal, during the fourth period in the one frame; and pixels positioned in an area defined by the scan lines and the data lines, the pixels being configured to store a current data signal during a period in which the pixels emit light, corresponding to a previous data signal. ### Claim 17 (depends on 16) The organic light emitting display of claim 16, wherein the previous data signal is the data signal supplied in a previous frame, and the current data signal is the data signal supplied in a current frame. ### Claim 18 (depends on 16) The organic light emitting display of claim 16, wherein the scan driver is configured to supply the scan signal concurrently to the scan lines during the third period. ### Claim 19 (depends on 16) The organic light emitting display of claim 16, wherein the data driver is configured to supply a reset voltage to the data lines during the third period. ### Claim 20 (depends on 19) The organic light emitting display of claim 19, wherein the reset voltage is set to a voltage in a voltage range of the data signal. ### Claim 21 (depends on 16) The organic light emitting display of claim 16, wherein each of the pixels is configured to control an amount of current flowing from a first power source to a second power source via an organic light emitting diode, corresponding to the previous data signal. ### Claim 22 (depends on 21) The organic light emitting display of claim 21, wherein the first power source is set to a first voltage during the fourth period, and is set to a second voltage different from the first voltage during the first to third periods. ### Claim 23 (depends on 22) The organic light emitting display of claim 22, wherein the second voltage is a voltage lower than the first voltage. ### Claim 24 (depends on 16) The organic light emitting display of claim 16, wherein each of the pixels comprises: an organic light emitting diode; a second driver configured according to an amount of current supplied from a first power source to the organic light emitting diode, corresponding to the previous data signal; and a first driver configured to store the current data signal, and to supply the previous data signal to the second driver. ### Claim 25 (depends on 24) The organic light emitting display of claim 24, wherein the first driver comprises: a second transistor coupled between a corresponding one of the data lines and a third node, the second transistor being configured to turn on when a scan signal is supplied to a corresponding one of the scan lines; a third transistor coupled between the third node and a second node commonly coupled to the first and second drivers, the third transistor being configured to turn on when the second control signal is supplied; and a second capacitor coupled between the third node and an initialization power source. ### Claim 26 (depends on 24) The organic light emitting display of claim 24, wherein the second driver comprises: a first transistor having a first electrode coupled to the first power source via a second node commonly coupled to the first and second drivers, the first transistor having a gate electrode coupled to a first node; a fifth transistor coupled between a second electrode of the first transistor and the first node, the fifth transistor being configured to turn on when the second control signal is supplied; a sixth transistor coupled between the first node and an initialization power source, the sixth transistor being configured to turn on when the first control signal is supplied; a seventh transistor coupled between the second node and the first power source, the seventh transistor being configured to turn on when the first control signal is supplied; an eighth transistor coupled between the second node and the first power source, the eighth transistor being configured to turn off when the emission control signal is supplied and to turn on otherwise; and a ninth transistor coupled between the second electrode of the first transistor and an anode electrode of the organic light emitting diode, the ninth transistor being configured to turn off when the emission control signal is supplied and to turn on otherwise. ### Claim 27 (depends on 26) The organic light emitting display of claim 26, wherein the initialization power source is set to a voltage lower than the data signal. ### Claim 28 (depends on 26) The organic light emitting display of claim 26, wherein the second driver further includes a fourth transistor coupled between the anode electrode of the organic light emitting diode and the initialization power source, the fourth transistor being configured to turn on when the first control signal is supplied. ### Claim 29 (depends on 26) The organic light emitting display of claim 26, wherein the second driver further comprises a fourth transistor coupled between the anode electrode of the organic light emitting diode and the initialization power source, the fourth transistor being configured to turn on when the second control signal is supplied. ### Claim 30 (depends on 26) The organic light emitting display of claim 26, wherein the second driver further comprises a fourth transistor positioned between the anode electrode of the organic light emitting diode and the second control line, the fourth transistor having a gate electrode coupled to the second control line. ### Claim 31 (depends on 26) The organic light emitting display of claim 26, wherein the second driver further comprises a photodiode coupled in parallel with a first capacitor between the first node and the first power source. ### Claim 32 (depends on 31) The organic light emitting display of claim 31, wherein the photodiode is configured to control an increment of a voltage at the first node, corresponding to a luminance of the organic light emitting diode. ### Claim 33 (depends on 31) The organic light emitting display of claim 31, wherein the photodiode is configured to control an increment of a voltage at the first node, in proportion to a luminance of the organic light emitting diode. ### Claim 34 (depends on 26) The organic light emitting display of claim 26, wherein the second driver further comprises a third capacitor coupled between the anode electrode of the organic light emitting diode and the second node. ### Claim 35 A pixel comprising: an organic light emitting diode; a second driver configured to control an amount of current supplied from a first power source to the organic light emitting diode, corresponding to a previous data signal; and a first driver configured to store a current data signal supplied from a data line and to supply the previous data signal to the second driver, wherein the second driver comprises: a fourth transistor coupled between an anode electrode of the organic light emitting diode and an initialization power source, the fourth transistor being configured to turn on when a first control signal is supplied; and a seventh transistor coupled between the first power source and a second node commonly coupled to the first and second drivers, the seventh transistor being configured to turn on when the first control signal is supplied. ### Claim 36 (depends on 35) The pixel of claim 35, wherein the first driver comprises: a second transistor coupled between the data line and a third node, the second transistor being configured to turn on when a scan signal is supplied to a scan line; a third transistor coupled between the third and second nodes, the third transistor being configured to turn on when a second control signal is supplied; and a second capacitor coupled between the third node and the initialization power source. ### Claim 37 (depends on 35) The pixel of claim 35, wherein the second driver comprises: a fifth transistor coupled between a first node coupled to a gate electrode of a first transistor and a second electrode of the first transistor, the fifth transistor being configured to turn on when a second control signal is supplied; a sixth transistor coupled between the initialization power source and the first node, the sixth transistor being configured to turn on when the first control signal is supplied; an eighth transistor coupled between the first power source and the second node, the second node being coupled to a first electrode of the first transistor, the eighth transistor being configured to turn off when an emission control signal is supplied and to turn on otherwise; a ninth transistor coupled between the second electrode of the first transistor and the anode electrode of the organic light emitting diode, the ninth transistor being configured to turn off when the emission control signal is supplied and to turn on otherwise; and a first capacitor coupled between the first node and the first power source. ### Claim 38 (depends on 37) The pixel of claim 37, wherein the eighth transistor has a turn-on period not overlapped with those of the fifth and sixth transistors. ### Claim 39 (depends on 37) The pixel of claim 37, wherein the fifth and sixth transistors have turn-on periods not overlapped with each other.