Display device and method of adjusting backlight brightness of display device

• US 9,824,636 B2
• Filed: 06/18/2015
• Issued: 11/21/2017
• Est. Priority Date: 02/04/2015
• Status: Expired due to Fees

• 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, Dong, Xue, Guo, Renwei, Liu, Peng, Li, Mubing, Miao, Jinghua
• Primary Examiner(s): SOTO LOPEZ, JOSE R
• Application Number:
  US14/743,490
• Publication Number:
  US 20160225323A1
• Time in Patent Office: 887 Days
• 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 an original brightness value of each pixel based on a gray value ratio of the original RGB signals of each pixel;

determining a backlight brightness value of each pixel based on a color of each pixel after the original RGB signals being converted, wherein the backlight brightness value of each pixel is the same as the original brightness value of the pixel only if all components of the gray value ratio of the RGB signals of the pixel have non-zero values or if none of the components of the gray value ratio of the RGB signals of the pixel have a non-zero value; and

performing a 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 original brightness value of each pixel based on the gray value ratio of the original RGB signals of each pixel comprises:

if one component of the gray value ratio of the original RGB signals of a pixel is nonzero, it is determined that one sub-pixel in the pixel is lighted; and

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

if two components of the gray value ratio of the original RGB signals of a pixel are nonzero, it is determined that two sub-pixels in the pixel are lighted; and

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

if three components of the gray value ratio of the original RGB signals of a pixel are nonzero, it is determined that three sub-pixels in the pixel are lighted; and

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

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

reading original brightness values of any pixels having one non-zero value among components of the gray value ratio of the RGB signals, and increasing the original brightness values by 1/12 to act as the backlight brightness values corresponding to those pixels.

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

reading original brightness values of any pixels having two non-zero values among components of the gray value ratio of the RGB signals, and increasing the original brightness values by ⅙

to act as the backlight brightness values corresponding to those pixels.

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

reading original brightness values of any pixels having one non-zero value among components of the gray value ratio of the RGB signals, and increasing the original brightness values by 1/12 to act as the backlight brightness values corresponding to those pixels.

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

reading original brightness values of any pixels having two non-zero values among components of the gray value ratio of the RGB signals, and increasing the original brightness values by ⅙

to act as the backlight brightness values corresponding to those pixels.

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

reading original brightness values of any pixels having two non-zero values among components of the gray value ratio of the RGB signals, and increasing the original brightness values by ⅙

to act as the backlight brightness values corresponding to those pixels.

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

reading original brightness values of any pixels having two non-zero values among components of the gray value ratio of the RGB signals, and increasing the original brightness values by ⅙

to act as the backlight brightness values corresponding to those pixels.

9. A display device, comprising:

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

a backlight drive unit configured to determine an 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 a color of each pixel after the original RGB signals being converted; and

perform a 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 a pulse width modulation signal of a backlight source,

wherein the backlight drive unit includes a first chip and a second chip, the first chip being configured to determine and store the color of each pixel, and calculate and store the original brightness value of each pixel based on the gray value ratio of the original RGB signals of each pixel, and the second chip being configured to use the original brightness values as the backlight brightness values only for pixels having non-zero values in all components of the gray value ratio of the RGB signals or having zero values in all components of the gray value ratio of the RGB signals.

10. The display device according to claim 9, wherein the first chip is further configured to:

if one component of the gray value ratio of the original RGB signals of a pixel is nonzero, it is determined that one sub-pixel in the pixel is lighted; and

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

if two components of the gray value ratio of the original RGB signals of a pixel are nonzero, it is determined that two sub-pixels in the pixel are lighted; and

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

if three components of the gray value ratio of the original RGB signals of a pixel are nonzero, it is determined that three sub-pixels in the pixel are lighted; and

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

11. The display device according to claim 9, wherein the second chip is further configured to:

read original brightness values of any pixels having one non-zero value among components of the gray value ratio of the RGB signals in the first chip, and increase the original brightness values by 1/12 to act as the backlight brightness values corresponding to those pixels; and

read original brightness values of any pixels having two non-zero values among components of the gray value ratio of the RGB signals, and increase the original brightness values by ⅙

to act as the adjusted backlight values corresponding to those pixels.

12. The display device according to claim 9, 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 the weighted average calculation on the backlight brightness values of all pixels, so as to obtain the whole backlight brightness adjustment value of the pixels.

13. The display device according to claim 10, 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 the weighted average calculation on the backlight brightness values of all pixels, so as to obtain the whole backlight brightness adjustment value of the pixels.

14. The display device according to claim 11, 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 the weighted average calculation on the backlight brightness values of all pixels, so as to obtain the whole backlight brightness adjustment value of the pixels.

15. A display device, comprising:

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

a backlight drive unit configured to determine an 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 a color of each pixel after the original RGB signals being converted; and

perform a 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 a pulse width modulation signal of a backlight source,

wherein the backlight drive unit includes a first chip and a second chip, the first chip being configured to determine and store the color of each pixel, and calculate and store and the original brightness value of each pixel based on the gray value ratio of the original RGB signals of each pixel, and the second chip being configured to;

read original brightness values of any pixels having one non-zero value among components of the gray value ratio of the RGB signals in the first chip, and increase the original brightness values by 1/12 to act as the backlight brightness values corresponding to those pixels;

read original brightness values of any pixels having two non-zero values among components of the gray value ratio of the RGB signals, and increase the original brightness values by ⅙

to act as the backlight brightness values corresponding to those pixels; and

read original brightness values of any pixels having non-zero values in all components of the gray value ratio of the RGB signals, and use the original brightness values as the backlight brightness values corresponding to those pixels.