Display device and driving method thereof

Patent metadata

Field	Value
Publication number	US-11423846-B2
Application number	US-202117240111-A
Country	US
Kind code	B2
Filing date	Apr 26, 2021
Priority date	Sep 2, 2020
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A display device includes a display panel, a data driving circuit which drives a plurality of data lines, a scan driving circuit which drives a plurality of scan lines, and a driving controller which controls the data driving circuit and the scan driving circuit such that the display panel is divided into a first display region and a second display region during a multi-frequency mode and the first display region and the second display region are respectively operated at different frequencies, where the driving controller changes an operation mode to a normal mode when a still image and a moving image are simultaneously displayed in the first display region during the multi-frequency mode and the duration of the still image reaches a predetermined time.

First claim

What is claimed is:

1. A display device comprising:
a display panel including a plurality of pixels respectively connected to corresponding data lines of a plurality of data lines and corresponding scan lines of a plurality of scan lines;
a data driving circuit which drives the plurality of data lines;
a scan driving circuit which drives the plurality of scan lines; and
a driving controller which controls the data driving circuit and the scan driving circuit such that the display panel is divided into a first display region and a second display region during a multi-frequency mode and the first display region and the second display region are respectively operated at first and second driving frequencies different from each other,
wherein the driving controller changes an operation mode to a normal mode in which each of the first display region and the second display region is operated at a third frequency, when a still image and a moving image are simultaneously displayed in the first display region during the multi-frequency mode and a duration of the still image reaches a predetermined time.

2. The display device of claim 1 , wherein the second driving frequency is lower than the first driving frequency during the multi-frequency mode.

3. The display device of claim 1 , wherein the first driving frequency is identical to the third frequency.

4. The display device of claim 1 , wherein the driving controller comprises:
a frequency mode determination part which determines the operation mode based on an image signal and a control signal and outputs a mode signal; and
a signal generator which outputs a data control signal and a scan control signal corresponding to the mode signal,
wherein the data control signal is provided to the data driving circuit, and the scan control signal is provided to the scan driving circuit.

5. The display device of claim 4 , wherein the frequency mode determination part changes the operation mode such that the mode signal represents the normal mode when the still image and the moving image are simultaneously displayed in the first display region during the multi-frequency mode and the duration of the still image reaches the predetermined time.

6. The display device of claim 4 , wherein the frequency mode determination part changes the operation mode such that the mode signal represents the normal mode when an average luminance of the still image displayed in the first display region is higher than a reference luminance.

7. The display device of claim 4 , wherein the frequency mode determination part changes the operation mode such that the mode signal represents the normal mode when an average luminance of the still image displayed in the first display region is higher than a reference luminance and the duration of the still image reaches the predetermined time.

8. The display device of claim 4 , wherein the frequency mode determination part changes the operation mode such that the mode signal represents the normal mode when the still image displayed in the first display region is a worst pattern and the duration of the still image reaches the predetermined time.

9. The display device of claim 4 , wherein the frequency mode determination part changes the mode signal to indicate the normal mode according to the duration of the still image when the still image displayed in the first display region is a worst pattern and a display area of the still image is greater than a reference area.

10. The display device of claim 9 , wherein the frequency mode determination part further:
changes a frequency of the second display region to a first intermediate frequency when the duration of the still image reaches a first reference time; and
changes a frequency of the second display region to a second intermediate frequency when the duration of the still image reaches a second reference time, wherein the second reference time is greater than the first reference time, and the second intermediate frequency is higher than the first intermediate frequency.

11. The display device of claim 10 , wherein the frequency mode determination part further changes the mode signal to indicate the normal mode when the duration of the still image reaches a third reference time, wherein the third reference time is greater than the second reference time.

12. The display device of claim 9 , wherein the frequency mode determination part further determines that the display area of the still image is greater than the reference area when a ratio of a length of the still image in a first direction to a length of the first display region in the first direction is equal to or greater than a predetermined value.

13. A method for driving a display device, the method comprising:
dividing a display panel into a first display region and a second display region during a multi-frequency mode;
driving the first display region at a first driving frequency, and driving the second display region at a second driving frequency different from the first driving frequency;
determining whether a still image and a moving image are simultaneously displayed in the first display region; and
changing an operation mode to a normal mode in which each of the first display region and the second display region is operated at a third frequency, when a duration of the still image reaches a predetermined time.

14. The method of claim 13 , further comprising changing the operation mode to the normal mode when an average luminance of the still image displayed in the first display region is higher than a reference luminance.

15. The method of claim 13 , wherein the changing the operation mode to the normal mode comprises:
determining whether an average luminance of the still image displayed in the first display region is higher than a reference luminance; and
changing the operation mode to the normal mode when the average luminance of the still image is higher than the reference luminance and the duration of the still image reaches the predetermined time.

16. The method of claim 13 , wherein the changing the operation mode to the normal mode comprises:
determining whether the still image displayed in the first display region is a worst pattern; and
changing the operation mode to the normal mode when the duration of the still image reaches the predetermined time.

17. The method of claim 13 , wherein the changing the operation mode to the normal mode comprises:
determining whether the still image displayed in the first display region is a worst pattern;
determining a display area of the still image is greater than a reference area; and
changing the second driving frequency according to the duration of the still image when the still image displayed in the first display region is the worst pattern and the display area of the still image is greater than the reference area.

18. The method of claim 17 , wherein the changing the second driving frequency comprises:
changing the second driving frequency to a first intermediate frequency when the duration of the still image reaches a first reference time; and
changing the second driving frequency to a second intermediate frequency when the duration of the still image reaches a second reference time, wherein the second reference time is greater than the first reference time, and the second intermediate frequency is higher than the first intermediate frequency.

19. The method of claim 18 , wherein the changing the operation mode to the normal mode comprises changing the operation mode to the normal mode when the duration o

Assignees

• Samsung Display Co Ltd

Inventors

• Yoon Changnoh
• Kwon Sangan
• Kim Soon-Dong
• Kim Taehoon
• Nam Hui
• Yun Eun Sil
• Lee Seungjae

Classifications

• G09G2380/02

  Flexible displays · CPC title

• G09G2320/0233

  Improving the luminance or brightness uniformity across the screen · CPC title

• G09G2320/103

  Detection of image changes, e.g. determination of an index representative of the image change · CPC title

• G09G2310/0262

  The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes · CPC title

• G09G3/3275 Primary

  Details of drivers for data electrodes · CPC title