Pixel circuit, display panel, display device, and driving method

Patent metadata

Field	Value
Publication number	US-11289021-B2
Application number	US-201716069414-A
Country	US
Kind code	B2
Filing date	Nov 15, 2017
Priority date	Feb 9, 2017
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

A pixel circuit, a display panel, a display device and a driving method are provided. The pixel circuit provides an initial signal having an excitation pulse to a control electrode of a driving transistor through a reset circuit in advance; and the initial signal having a preset voltage is provided to the control electrode of the driving transistor after a preset duration.

First claim

What is claimed is:

1. A pixel circuit, comprising: a reset circuit, a data writing circuit, a driving transistor and a light emitting device,
wherein the driving transistor comprises a control electrode, a first electrode and a second electrode, the light emitting device comprises a first terminal and a second terminal, the first electrode of the driving transistor is configured to be connected to a first power supply terminal, the second electrode of the driving transistor is configured to be connected to the second terminal of the light emitting device, and the first terminal of the light emitting device is configured to be connected to a second power supply terminal;
the reset circuit is connected to the control electrode of the driving transistor, and is configured to provide an initial signal having an excitation pulse to the control electrode of the driving transistor under control of a reset signal, and provide the initial signal having a preset voltage to the control electrode of the driving transistor after a preset duration, and there is a voltage difference between a voltage of the excitation pulse and the preset voltage; and
the data writing circuit is configured to provide a data signal to the driving transistor under control of a scanning signal;
in a period during which the initial signal having the excitation pulse is provided and in a period during which the initial signal having the preset voltage is provided, the reset signal remains unchanged, and the scanning signal remains unchanged.

2. A display panel, comprising a plurality of sub-pixel units, each of the sub-pixel units comprising the pixel circuit according to claim 1 .

3. The display panel according to claim 2 , further comprising a display driver, wherein the display driver is configured to provide the initial signal having the excitation pulse to the control electrode of the driving transistor, and provide the initial signal having the preset voltage to the control electrode of the driving transistor after the preset duration.

4. The display panel according to claim 3 , wherein the display driver inputs the initial signal to the pixel circuits of the sub-pixel units in a same row through a same signal line; and
the display driver is further configured to determine a period duration of the initial signal according to a duration of scanning one row of sub-pixel units in the display panel.

5. The display panel according to claim 2 , further comprising a display driver, wherein the display driver is configured to determine the preset voltage of the initial signal according to a type of the driving transistor in the pixel circuit, and determine the excitation pulse of the initial signal according to the determined preset voltage and a duration of scanning one row of sub-pixel units in the display panel;
when the pixel circuit is in an excitation phase, the excitation pulse is input to the reset circuit; and
when the pixel circuit is in a reset phase, the preset voltage is input to the reset circuit.

6. A display device, comprising the display panel according to claim 2 .

7. A driving method of the display panel according to claim 2 , comprising:
determining the preset voltage of the initial signal according to a type of the driving transistor in the pixel circuit, and determining the excitation pulse of the initial signal according to the determined preset voltage and a duration of scanning one row of the pixel circuits in the display panel;
when the pixel circuit is determined to be in an excitation phase, inputting the excitation pulse to the reset circuit; and
when the pixel circuit is determined to be in a reset phase, inputting the preset voltage to the reset circuit.

8. The pixel circuit according to claim 1 , further comprising: a voltage input circuit, a compensation control circuit, a voltage storage circuit, a light emission control circuit and a first node;
wherein the voltage input circuit is connected to the first node and the first power supply terminal, and is configured to provide a voltage signal of the first power supply terminal to the first node under control of the reset signal;
the data writing circuit is connected to the first node, and is configured to provide the data signal to the first node under control of the scanning signal;
the compensation control circuit is connected to the control electrode of the driving transistor and the second electrode of the driving transistor, and is configured to electrically conduct the control electrode of the driving transistor and the second electrode of the driving transistor under control of the scanning signal;
the voltage storage circuit is connected to the control electrode of the driving transistor and the first node, and is configured to charge or discharge under control of a signal of the first node and a signal of the control electrode of the driving transistor, and keep a voltage difference between the first node and the control electrode of the driving transistor stable when the control electrode of the driving transistor is in a floating state; and
the light emission control circuit is configured, under control of a light emission control signal, to provide a reference signal to the first node and provide a signal of the second electrode of the driving transistor to the second terminal of the light emitting device.

9. The pixel circuit according to claim 8 , wherein the reset circuit comprises: a first switching transistor,
wherein a control electrode of the first switching transistor is configured to receive the reset signal, a first electrode of the first switching transistor is configured to receive the initial signal, and a second electrode of the first switching transistor is connected to the control electrode of the driving transistor.

10. The pixel circuit according to claim 8 , wherein the voltage input circuit comprises a second switching transistor,
wherein a control electrode of the second switching transistor is configured to receive the reset signal, a first electrode of the second switching transistor is connected to the first power supply terminal, and a second electrode of the second switching transistor is connected to the first node.

11. The pixel circuit according to claim 8 , wherein the compensation control circuit comprises a fourth switching transistor,
wherein a control electrode of the fourth switching transistor is configured to receive the scanning signal, a first electrode of the fourth switching transistor is connected to the control electrode of the driving transistor, and a second electrode of the fourth switching transistor is connected to the second electrode of the driving transistor.

12. The pixel circuit according to claim 8 , wherein the light emission control circuit comprises a fifth switching transistor and a sixth switching transistor,
wherein a control electrode of the fifth switching transistor is configured to receive the light emission control signal, a first electrode of the fifth switching transistor is configured to receive the reference signal, and a second electrode of the fifth switching transistor is connected to the first node; and
a control electrode of the sixth switching transistor is configured to receive the light emission control signal, a first electrode of the sixth switching transistor is connected to the second electrode of the driving transistor, and a second electrode of the sixth switching transistor is connected to the second terminal of the light emitting device.

13. The pixel circuit according to claim 8 , wherein the voltage storage circuit comprises at least one capacitor,
wherein a first terminal of the capacitor is con

Assignees

• Boe Technology Group Co Ltd
• Ordos Yuansheng Optoelectronics Co Ltd

Inventors

• Li Zihua
• Liu Qi
• Zhang Guoping
• Liu Jing
• Yang Yuqing
• Li Xiping

Classifications

• G09G3/3258 Primary

  with pixel circuitry controlling the voltage across the light-emitting element · CPC title

• G09G2300/0861

  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 title

• G09G2300/043

  Compensation electrodes or other additional electrodes in matrix displays related to distortions or compensation signals, e.g. for modifying TFT threshold voltage in column driver · CPC title

• G09G3/3233 Primary

  with pixel circuitry controlling the current through the light-emitting element · CPC title

• G09G2310/061

  for resetting or blanking · CPC title