Display Device and Method of Adjusting Backlight Brightness of Display Device

• US 20160225323A1
• Filed: 06/18/2015
• Published: 08/04/2016
• Est. Priority Date: 02/04/2015
• Status: Active Grant

• Current Assignee: Beijing BOE Optoelectronics Technology Co Ltd. (BOE Technology Group Co., Ltd.), BOE Technology Group Co., Ltd.
• Original Assignee: Beijing BOE Optoelectronics Technology Co Ltd. (BOE Technology Group Co., Ltd.), BOE Technology Group Co., Ltd.
• Inventors: Lu, Pengcheng, Chen, Zhongjun, Li, Mubing, Miao, Jinghua, Dong, Xue, Guo, Renwei, Liu, Peng
• Granted Patent: US 9,824,636 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

A display device and a method of adjusting backlight brightness of the display device are provided. The method includes converting original RGB signals of each pixel to corresponding RGBW signals; determining the color and original brightness value of each pixel based on the gray value ratio of the original RGB signals of each pixel; determining the backlight brightness value of each pixel based on the color of each pixel after the original RGB signals being converted; and performing weighted average calculation on the backlight brightness values of each pixel after the signals being converted, so as to obtain a whole backlight brightness adjustment value of all pixels.

Claims

1. A method of adjusting backlight brightness of a display device, comprising:

converting original RGB signals of each pixel to corresponding RGBW signals;

determining a color and original brightness value of each pixel based on a gray value ratio of the original RGB signals of each pixel;

determining the backlight brightness value of each pixel based on the color of each pixel after the original RGB signals being converted; and

performing weighted average calculation on the backlight brightness values of all pixels after the signals being converted, so as to obtain a whole backlight brightness adjustment value of the pixels.

2. The method of adjusting backlight brightness according to claim 1, wherein the determining of the color and original brightness value of each pixel based on the gray value ratio of the original RGB signals of each pixel comprises:

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=X;

0;

0, it is determined that a sub-pixel R in the pixel is lighted, the color of the pixel is pure red R; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=0;

Y;

0, it is determined that a sub-pixel G in the pixel is lighted, the color of the pixel is pure green G; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=0;

0;

Z, it is determined that a sub-pixel B in the pixel is lighted, the color of the pixel is pure blue B; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=0;

Y;

Z, it is determined that sub-pixels G and B in the pixel are lighted, the color of the pixel is cyan C; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=X;

0;

Z, it is determined that sub-pixels R and B in the pixel are lighted, the color of the pixel is magenta M; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=X;

Y;

0, it is determined that sub-pixels R and G in the pixel are lighted, the color of the pixel is yellow Y; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=255;

255;

255, it is determined that sub-pixels R, G and B in the pixel are lighted, the color of the pixel is white W; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=1;

1;

1 and each of gray values is less than 255, it is determined that sub-pixels R, G and B in the pixel are lighted, the color of the pixel is gray; and

the original brightness value of the pixel is calculated and stored; and

if the gray value ratio of the RGB signals of a pixel does not fall into above situations, it is determined that sub-pixels R, G and B in the pixel are lighted, the color of the pixel is other color; and

the original brightness value of the pixel is calculated and stored;

where each of X, Y and Z is an integer greater than or equal to 1 and is less than or equal to 255.

3. The method of adjusting backlight brightness according to claim 1, further comprising:

reading original brightness values of pixels which are pure red R, pure green G and pure blue B, and increasing the original brightness values by 1/12 to act as the adjusted brightness values.

4. The method of adjusting backlight brightness according to claim 1, further comprising:

reading original brightness values of pixels which are cyan C, magenta M and yellow Y, and increasing the original brightness values by ⅙

to act as the adjusted brightness values.

5. The method of adjusting backlight brightness according to claim 1, further comprising:

reading original brightness values of pixels which are white W, gray and other color, and remaining the original brightness values unchanged to act as the adjusted brightness values.

10. The method of adjusting backlight brightness according to claim 2, further comprising:

reading original brightness values of pixels which are pure red R, pure green G and pure blue B, and increasing the original brightness values by 1/12 to act as the adjusted brightness values.

11. The method of adjusting backlight brightness according to claim 2, further comprising:

reading original brightness values of pixels which are cyan C, magenta M and yellow Y, and increasing the original brightness values by ⅙

to act as the adjusted brightness values.

12. The method of adjusting backlight brightness according to claim 3, further comprising:

reading original brightness values of pixels which are cyan C, magenta M and yellow Y, and increasing the original brightness values by ⅙

to act as the adjusted brightness values.

13. The method of adjusting backlight brightness according to claim 10, further comprising:

reading original brightness values of pixels which are cyan C, magenta M and yellow Y, and increasing the original brightness values by ⅙

to act as the adjusted brightness values.

14. The method of adjusting backlight brightness according to claim 2, further comprising:

reading original brightness values of pixels which are white W, gray and other color, and remaining the original brightness values unchanged to act as the adjusted brightness values.

15. The method of adjusting backlight brightness according to claim 3, further comprising:

reading original brightness values of pixels which are white W, gray and other color, and remaining the original brightness values unchanged to act as the adjusted brightness values.

16. The method of adjusting backlight brightness according to claim 4, further comprising:

reading original brightness values of pixels which are white W, gray and other color, and remaining the original brightness values unchanged to act as the adjusted brightness values.

17. The method of adjusting backlight brightness according to claim 13, further comprising:

reading original brightness values of pixels which are white W, gray and other color, and remaining the original brightness values unchanged to act as the adjusted brightness values.

6. A display device, comprising:

signal decomposition unit configured to convert original RGB signals of each pixel to corresponding RGBW signals;

a backlight drive unit configured to determine a color and original brightness value of each pixel based on a gray value ratio of the original RGB signals of each pixel, determine a backlight brightness value of each pixel based on the color of each pixel after the original RGB signals being converted; and

perform weighted average calculation on the backlight brightness values of all pixels after the signals being converted, so as to obtain a whole backlight brightness adjustment value of the pixels; and

a backlight control unit configured to receive the whole backlight brightness adjustment value calculated by the backlight drive unit, and adjust the whole backlight brightness by controlling a duty ratio of pulse width modulation signal of a backlight source.

7. The display device according to claim 6, wherein the backlight drive unit comprises a first chip, which is configured to determine and store the color of each pixel, and calculate and store and original brightness value of each pixel based on the gray value ratio of the original RGB signals of each pixel, comprising the following situations:

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=X;

0;

0, it is determined that a sub-pixel R in the pixel is lighted, the color of the pixel is pure red R; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=0;

Y;

0, it is determined that a sub-pixel G in the pixel is lighted, the color of the pixel is pure green G; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=0;

0;

Z, it is determined that a sub-pixel B in the pixel is lighted, the color of the pixel is pure blue B; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=0;

Y;

Z, it is determined that sub-pixels G and B in the pixel are lighted, the color of the pixel is cyan C; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=X;

0;

Z, it is determined that sub-pixels R and B in the pixel are lighted, the color of the pixel is magenta M; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=X;

Y;

0, it is determined that sub-pixels R and G in the pixel are lighted, the color of the pixel is yellow Y; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=255;

255;

255, it is determined that sub-pixels R, G and B in the pixel are lighted, the color of the pixel is white W; and

the original brightness value of the pixel is calculated and stored;

if the gray value ratio of the RGB signals of a pixel is R;

G;

B=1;

1;

1 and each of gray values is less than 255, it is determined that sub-pixels R, G and B in the pixel are lighted, the color of the pixel is gray; and

the original brightness value of the pixel is calculated and stored; and

if the gray value ratio of the RGB signals of a pixel does not fall into above situations, it is determined that sub-pixels R, G and B in the pixel are lighted, the color of the pixel is other color; and

the original brightness value of the pixel is calculated and stored;

where each of X, Y and Z is an integer greater than or equal to 1 and is less than or equal to 255.

8. The display device according to claim 6, wherein the backlight drive unit further comprises a second chip, which is configured to:

read original brightness values of pixels which are pure red R, pure green G and pure blue B in the first chip, and increase the original brightness values by 1/12 to act as the adjusted brightness values;

read original brightness values of pixels which are cyan C, magenta M and yellow Y, and increase the original brightness values by ⅙

to act as the adjusted brightness values; and

read original brightness values of pixels which are white W, gray and other color, and remain the original brightness values unchanged to act as the adjusted brightness values.

9. The display device according to claim 6, the backlight drive unit further comprises a third chip, which is configured to read the backlight brightness values of each pixel in the second chip after the signals being converted, and perform weighted average calculation on the backlight brightness values of all pixels, so as to obtain the whole backlight brightness adjustment value of the pixels.

18. The display device according to claim 7, wherein the backlight drive unit further comprises a second chip, which is configured to:

read original brightness values of pixels which are pure red R, pure green G and pure blue B in the first chip, and increase the original brightness values by 1/12 to act as the adjusted brightness values;

read original brightness values of pixels which are cyan C, magenta M and yellow Y, and increase the original brightness values by ⅙

to act as the adjusted brightness values; and

read original brightness values of pixels which are white W, gray and other color, and remain the original brightness values unchanged to act as the adjusted brightness values.

19. The display device according to claim 7, the backlight drive unit further comprises a third chip, which is configured to read the backlight brightness values of each pixel in the second chip after the signals being converted, and perform weighted average calculation on the backlight brightness values of all pixels, so as to obtain the whole backlight brightness adjustment value of the pixels.

20. The display device according to claim 8, the backlight drive unit further comprises a third chip, which is configured to read the backlight brightness values of each pixel in the second chip after the signals being converted, and perform weighted average calculation on the backlight brightness values of all pixels, so as to obtain the whole backlight brightness adjustment value of the pixels.