Display panel, method of driving the same and display device

Patent metadata

Field	Value
Publication number	US-11640786-B2
Application number	US-202017417153-A
Country	US
Kind code	B2
Filing date	Nov 9, 2020
Priority date	Nov 9, 2020
Publication date	May 2, 2023
Grant date	May 2, 2023

Abstract

A driving method includes, at a first display brightness value, inputting a pulse-width modulation signal with a duty ratio of X, and controlling a light-emitting driving current of a sub-pixel unit to be M, wherein X and M are obtained according to a first modulation rule; and at a second display brightness value, inputting the pulse-width modulation signal with a duty ratio of Y1, and controlling the light-emitting driving current of the sub-pixel unit to be N1, wherein the first display brightness value is greater than the second one, wherein, when the duty ratio and the light-emitting driving current corresponding to the second display brightness value are obtained according to the first modulation rule, the duty ratio corresponding to the second display brightness value is Y2, the light-emitting driving current corresponding to the second display brightness value is N2, Y1 is smaller than Y2, and N1 is greater than N2.

First claim

What is claimed is:

1. A method of driving a display panel, comprising:
providing the display panel, wherein the display panel comprises a plurality of sub-pixel units;
at a first display brightness value, inputting a pulse-width modulation signal with a duty ratio of X to the display panel, and controlling a light-emitting driving current of the sub-pixel unit to be M, wherein the duty ratio of the pulse-width modulation signal is in positive correlation with a light-emitting duration of the sub-pixel unit in one driving cycle, wherein X and M are obtained according to a first modulation rule, X>0, and M>0; and
at a second display brightness value, inputting the pulse-width modulation signal with a duty ratio of Y1 to the display panel, and controlling the light-emitting driving current of the sub-pixel unit to be N1, wherein the first display brightness value is greater than the second display brightness value, Y1>0, and N1>0,
wherein, when the pulse-width modulation signal and the light-emitting driving current corresponding to the second display brightness value are obtained according to the first modulation rule, the duty ratio of the pulse-width modulation signal corresponding to the second display brightness value is Y2, the light-emitting driving current corresponding to the second display brightness value is N2, Y2>0, N2>0, Y1 is smaller than Y2, and N1 is greater than N2.

2. The method of driving the display panel according to claim 1 , wherein the second display brightness value is equal to or less than K1, and the first display brightness value is greater than K1.

3. The method of driving the display panel according to claim 2 , wherein K1 is equal to or greater than 2 nits, and K1 is equal to or less than 32 nits.

4. The method of driving the display panel according to claim 1 , wherein:
the sub-pixel unit comprises a pixel driving circuit and a light-emitting unit,
the pixel driving circuit comprises a first switching element connected between a first power supply terminal and a light-emitting unit, and the first switching unit is configured to turn on the first power supply terminal and the light-emitting unit in response to an enable signal, and
the duty ratio of the pulse-width modulation signal is in positive correlation with a duty ratio of the enable signal.

5. The method of driving the display panel according to claim 4 , wherein:
the display panel comprises a gate electrode driving circuit, and the gate electrode driving circuit is configured to provide the enable signal to the first switching unit, and
the pulse-width modulation signal is an initial trigger signal of the gate electrode driving circuit.

6. The method of driving the display panel according to claim 1 , wherein Y1 is smaller than X, and N1 is greater than M.

7. The method of driving the display panel according to claim 1 , wherein, when the pulse-width modulation signal and the light-emitting driving current corresponding to the second display brightness value are obtained according to the first modulation rule, the second display brightness value corresponds to a first gamma level, and controlling the light-emitting driving current of the sub-pixel unit to be M comprises:
controlling the light-emitting driving current of the sub-pixel unit based on a second gamma level,
wherein the light-emitting driving current generated based on the second gamma level is greater than the light-emitting driving current generated based on the first gamma level at a same gray scale.

8. The method of driving the display panel according to claim 1 , wherein N1*Y1 is equal to N2*Y2.

9. A method of driving a display panel, comprising:
at a first display brightness value, inputting a pulse-width modulation signal with a duty ratio of X to the display panel, and controlling a light-emitting driving current of a sub-pixel unit in the display panel to be M; and
at a second display brightness value, inputting the pulse-width modulation signal with a duty ratio of Y1 to the display panel, and controlling the light-emitting driving current of the sub-pixel unit in the display panel to be N1,
wherein the duty ratio of the pulse-width modulation signal is in positive correlation with a light-emitting duration of the sub-pixel unit in one driving cycle, the first display brightness value is greater than the second display brightness value, N1>M, and Y1<X.

10. The method of driving the display panel according to claim 9 , wherein the second display brightness value is equal to or less than K1, and the first display brightness value is greater than K1.

11. The method of driving the display panel according to claim 9 , wherein:
the sub-pixel unit comprises a pixel driving circuit and a light-emitting unit,
the pixel driving circuit comprises a first switching element connected between a first power supply terminal and a light-emitting unit, and the first switching unit is configured to turn on the first power supply terminal and the light-emitting unit in response to an enable signal, and
the duty ratio of the pulse-width modulation signal is in positive correlation with a duty ratio of the enable signal.

12. The method of driving the display panel according to claim 11 , wherein:
the display panel comprises a gate electrode driving circuit, and the gate electrode driving circuit is configured to provide the enable signal to the first switching unit, and
the pulse-width modulation signal is an initial trigger signal of the gate electrode driving circuit.

13. The method of driving the display panel according to claim 9 , wherein X and M are obtained according to a first modulation rule and, when the pulse-width modulation signal and the light-emitting driving current corresponding to the second display brightness value are obtained according to the first modulation rule, the second display brightness value corresponds to a first gamma level, and controlling the light-emitting driving current of the sub-pixel unit to be M comprises:
controlling the light-emitting driving current of the sub-pixel unit based on a second gamma level,
wherein the light-emitting driving current generated based on the second gamma level is greater than the light-emitting driving current generated based on the first gamma level at a same gray scale.

14. A display panel, comprising:
a plurality of sub-pixel units, wherein each of the sub-pixel units comprises a pixel driving circuit, the pixel driving circuit comprising a first switching element connected between a first power supply terminal and a light-emitting unit, and the first switching unit being configured to turn on the first power supply terminal and the light-emitting unit in response to an enable signal; and
a gate electrode driving circuit configured to provide the enable signal to the first switching unit;
a source electrode driving circuit configured to input a driving voltage to the pixel driving circuit;
a gamma circuit comprising a plurality of sets of gamma registers, wherein each set of gamma registers stores a set of gamma data, each set of gamma data corresponds to a gamma level, and each of the gamma levels corresponds to a display brightness value and a pulse-width modulation signal;
a processing circuit configured to, according to the gamma levels corresponding to each set of gamma registers as well as the display brightness value and the pulse-width modulation signal corresponding to each of the gamma levels, obtain the pulse-width modulation signal and the gamma level corresponding to any display brightness value; and
a driving circuit configured to call the pulse-width modulation signal and the gamma leve

Assignees

• Chengdu Boe Optoelect Tech Co
• Boe Technology Group Co Ltd

Inventors

• Chen Wenbin
• Yan Rongjian
• Song Guangjun
• Yu Zhaowei
• Yang Yamin
• Zhang Wenqiang

Classifications

• G09G2320/0238

  Improving the black level · CPC title

• G09G2320/0653

  Controlling or limiting the speed of brightness adjustment of the illumination source · CPC title

• G09G2320/0673

  for control of gamma adjustment, e.g. selecting another gamma curve · CPC title

• G09G2310/0251

  Precharge or discharge of pixel before applying new pixel voltage · CPC title

• G09G5/10

  Intensity circuits · CPC title