ORGANIC LIGHT-EMITTING DISPLAY DEVICE

• US 20180158414A1
• Filed: 11/30/2017
• Published: 06/07/2018
• Est. Priority Date: 12/01/2016
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: LEE, Wook
• Granted Patent: US 10,984,717 B2
• Time in Patent Office: Days
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: 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
• CPC Class Codes: G09G 2310/0256 with the purpose of reversing the voltage across a light emitting or modulating element within a pixel
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/045 Compensation of drifts in the characteristics of light emitting or modulating elements
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3258 with pixel circuitry controlling the voltage across the light-emitting element
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals

Abstract

An organic light-emitting display device includes a plurality of pixels, each of which is connected to a scan line, a data line, a first power line and a second power line, and includes a light-emitting diode. A voltage applied to an anode of the light-emitting diode is higher than a voltage applied to a cathode in a first operation period, and a voltage applied to the anode of the light-emitting diode is lower than a voltage applied to the cathode in at least a part of a second operation period different from the first operation period.

Claims

1. An organic light-emitting display device comprising:

a plurality of pixels, wherein each of the pixels is connected to a scan line, a data line, a first power line and a second power line, and each of the pixels comprises a light-emitting diode,

wherein a voltage applied to an anode of the light-emitting diode in a first operation period is higher than a voltage applied to a cathode of the light-emitting diode in the first operation period, and

wherein a voltage applied to the anode of the light-emitting diode in a part of a second operation period, which is different from the first operation period, is lower than a voltage applied to the cathode of the light-emitting diode in the part of the second operation period.

2. The organic light-emitting display device according to claim 1, wherein

the light-emitting diode emits light in the first operation period, and

the light-emitting diode is turned off in the part of the second operation period.

3. The organic light-emitting display device according to claim 1, wherein

the light-emitting diode is driven with a scan signal supplied to the scan line, a data signal supplied to the data line, a first supply voltage supplied to the first power line, and a second supply voltage supplied to the second power line, and

each of the pixels further comprises:

a first switching element connected to the first power line and the light-emitting diode; and

a second switching element connected to the data line and the scan line, wherein

the first supply voltage is applied to the anode of the light-emitting diode via the first switching element,

the data signal is supplied to a control terminal of the first switching element via the second switching element, and

the scan signal is supplied to a control terminal of the second switching element.

4. The organic light-emitting display device according to claim 1, wherein

the first power line is supplied with the first supply voltage to be applied to the anode of the light-emitting diode,

the second power line is supplied with the second supply voltage or a third supply voltage to be applied to the cathode of the light-emitting diode, and

the second supply voltage and the third supply voltage have different voltage levels from each other.

5. The organic light-emitting display device according to claim 4, wherein

the second supply voltage is supplied to the second power line in the first operation period, and

the third supply voltage is supplied to the second power line in the part of the second operation period.

6. The organic light-emitting display device according to claim 5, wherein

the second supply voltage has a voltage level lower than a voltage level of the first supply voltage, and

the third supply voltage has a voltage level higher than the voltage level of the first supply voltage.

7. The organic light-emitting display device according to claim 1, wherein

the data signal has a voltage level corresponding to a grayscale of the light-emitting diode in the first operation period, and

the data signal has a voltage level lower than a voltage level of the voltage applied to the cathode of the light-emitting diode in the part of the second operation period.

8. The organic light-emitting display device according to claim 7, wherein

each of the pixels further comprises a third switching element,

wherein the anode of the light-emitting diode is connected to the data line via the third switching element.

9. The organic light-emitting display device according to claim 8, wherein the third switching element is turned on when the data signal has the voltage level lower than the voltage level of the voltage applied to the cathode of the light-emitting diode in the part of the second operation period.

10. The organic light-emitting display device according to claim 1, wherein

the plurality of pixels displays an image at each frame,

each frame comprises a porch interval and first to n^th data write intervals, wherein n is a natural number,

the first operation period corresponds to the first to n^th data write intervals, and

the second operation period corresponds to the porch interval.

11. The organic light-emitting display device according to claim 10, wherein the plurality of pixels is arranged inn rows.

12. The organic light-emitting display device according to claim 11, wherein the voltage applied to the anode of the light-emitting diode in each of the pixels in a part of the pouch interval is lower than the voltage applied to the cathode of the light-emitting diode in the part of the pouch interval.

13. The organic light-emitting display device according to claim 1, wherein

the plurality of pixels displays an image at each frame,

each frame comprises first to n^th compensation intervals and first to n^th data write intervals, wherein n is a natural number greater than 1,

the first operation period corresponds to the first to n^th data write intervals, and

the second operation period corresponds to the first to n^th compensation intervals.

14. The organic light-emitting display device according to claim 13, wherein the first to the n^th compensation intervals and the first to the n^th data write intervals are alternated arranged in each frame.

15. The organic light-emitting display device according to claim 13, wherein the plurality of pixels is arranged inn rows.

16. The organic light-emitting display device according to claim 15, wherein a voltage applied to the anode of the light-emitting diode in a pixel disposed at a k-th row is lower than the voltage applied to the cathode of the light-emitting diode in the pixel disposed at the k-th row in a part of a k-th compensation interval, where k is a natural number equal to or less than n.

17. The organic light-emitting display device according to claim 1, wherein

the plurality of pixels is connected to an initialization power line,

the first power line is supplied with a first supply voltage to be applied to the anode of the light-emitting diode,

the second power line is supplied with a second supply voltage to be applied to the cathode of the light-emitting diode, and

the initialization power line is supplied with an initialization supply voltage to be applied to the anode of the light-emitting diode.

18. The organic light-emitting display device according to claim 17, wherein

the first supply voltage has a voltage level higher than a voltage level of the second supply voltage, and

the initialization supply voltage has a voltage level lower than a voltage level of the second supply voltage.

19. The organic light-emitting display device according to claim 18, wherein

the first supply voltage is applied the anode of the light-emitting diode in the first operation period, and

the initialization supply voltage is applied the anode of the light-emitting diode in the part of the second operation period.

20. The organic light-emitting display device according to claim 17, wherein

each of the pixels further comprises an initialization switching element,

wherein the initialization power line is connected to the anode of the light-emitting diode via the initialization switching element.