Luminance compensation method and luminance compensation device of display device, and display device

• US 9,704,432 B2
• Filed: 10/14/2014
• Issued: 07/11/2017
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: BOE Technology Group Co., Ltd.
• Inventors: Wu, Zhongyuan, Zhang, Xiangfei, Zhou, Yang
• Primary Examiner(s): Johnson, Gerald
• Application Number:
  US14/646,086
• Publication Number:
  US 20160267838A1
• Time in Patent Office: 1,001 Days
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/029 by monitoring one or more pixels in the display panel, e.g. by monitoring a fixed reference pixel
• CPC Class Codes: G09G 2320/045 Compensation of drifts in the characteristics of light emitting or modulating elements
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 2360/14 Detecting light within display terminals, e.g. using a single or a plurality of photosensors
• CPC Class Codes: G09G 2360/141 the light conveying information used for selecting or modulating the light emitting or modulating element
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

A luminance compensation method and a luminance compensation device of a display device, and the display device are provided. The luminance compensation method of the display device, includes: obtaining an input grayscale value of one of a plurality of sub-pixels corresponding to the display device of an input image, and obtaining a functional relationship between a compensated grayscale value and the input grayscale value corresponding to the sub-pixel; obtaining the compensated grayscale value corresponding to the sub-pixel by using the functional relationship, and performing luminance compensation on the sub-pixel according to the compensated grayscale value; and executing the above operations repeatedly for each of the plurality of sub-pixels of the input image.

Claims

1. A luminance compensation method of a display device, comprising:

obtaining an input grayscale value of one of a plurality of sub-pixels corresponding to the display device of an input image, and obtaining a functional relationship between a compensated grayscale value and the input grayscale value corresponding to the sub-pixel;

obtaining the compensated grayscale value corresponding to the sub-pixel by using the functional relationship, and performing luminance compensation on the sub-pixel according to the compensated grayscale value; and

executing the above operations repeatedly for each of the plurality of sub-pixels of the input image;

wherein the functional relationship is determined for each of the sub-pixels of the display device, according to a test luminance value and a target luminance value of the sub-pixel under a plurality of test a terns of different test grayscale values.

2. The luminance compensation method according to claim 1, wherein the functional relationship is determined by steps of:

determining a functional relationship between the test luminance value and the test grayscale value of each sub-pixel of the display device, according to a plurality of test grayscale values and test luminance values under the plurality of test grayscale values;

determining a functional relationship between the target luminance value and the test grayscale value of the sub-pixel, according to a plurality of test grayscale values and target luminance values under the plurality of test grayscale values;

determining a grayscale compensation amount corresponding to each of the test grayscale values of the sub-pixel, according to the functional relationship between the test luminance value and the test grayscale value and the functional relationship between the target luminance value and the test grayscale value;

determining a functional relationship between the compensated grayscale value and the test grayscale value corresponding to the sub-pixel, according to the grayscale compensation amount corresponding to each of the test grayscale values of the sub-pixel, the functional relationship between the compensated grayscale value and the test grayscale value corresponding to the sub-pixel being just the functional relationship between the compensated grayscale value and the input grayscale value corresponding to the sub-pixel.

3. The luminance compensation method according to claim 2, before the functional relationship is determined, further comprising:

selecting a part of grayscale values from among all grayscale values of the display device as the plurality of test grayscale values;

determining different test patterns according to the plurality of test grayscale values selected;

collecting the test luminance values under the different test patterns by using an image sensor.

4. The luminance compensation method according to claim 2, wherein, the functional relationship between the test luminance value and the test grayscale value of each of the sub-pixels of the display device, complies with a formula below:

L_ij,x=A_ij,nG_xⁿ+A<sub>ij,n−

1</sub>G_x<sup>n−

1</sup>+ . . . +A_ij,1G_x+A_ij,0,

where, L_ij,x is a test luminance value corresponding to an input grayscale value G_x of a sub-pixel in i-th row and j-th column, G_x is the input grayscale value corresponding to the sub-pixel, A_ij,n is a coefficient of an n-th expansion item of G_x, n is a natural number, and i,j are positive integers.

5. The luminance compensation method according to claim 2, wherein, the target luminance value of each of the sub-pixels under each of the test grayscale values is preset.

6. The luminance compensation method according to claim 2, wherein, the target luminance value of each of the sub-pixels under each of the test grayscale values is obtained by averaging the test luminance values of the plurality of sub-pixels under the test grayscale value.

7. The luminance compensation method according to claim 5, wherein, the functional relationship between the target luminance value and the test grayscale value of the sub-pixel complies with a formula below:

L_t,x=B_t,nG_xⁿ+B<sub>t,n−

1</sub>G_x<sup>n−

1</sup>+ . . . +B_t,1G_x+B_t,0,

where, L_t,x is a target luminance value corresponding to an input grayscale value G_x, B_t,n is a coefficient of an n-th expansion item of G_x, n is a natural number, and i,j are positive integers.

8. The luminance compensation method according to claim 1, wherein, the obtaining a functional relationship between a compensated grayscale value and the input grayscale value corresponding to the sub-pixel includes:

obtaining the functional relationship from a volatile memory.

9. The luminance compensation method according to claim 8, wherein, the obtaining a functional relationship between a compensated grayscale value and the input grayscale value corresponding to the sub-pixel further includes:

reading the functional relationship corresponding to the sub-pixel from a non-volatile memory to the volatile memory, before obtaining the functional relationship from the volatile memory.

10. The luminance compensation method according to claim 1, wherein, the functional relationship between the compensated grayscale value and the input grayscale value corresponding to each of the plurality of sub-pixels, complies with a formula below:

G_ij,x′

=C_ij,nG_xⁿ+C<sub>ij,n−

1</sub>G_x<sup>n−

1</sup>+ . . . +C_ij,1G_x+C_ij,0,

where, G_ij,x′

is a compensated grayscale value corresponding to a sub-pixel in i-th row and j-th column, G_x is an input grayscale value corresponding to the sub-pixel, C_ij,n is a coefficient of an n-th expansion item of G_x, n is a natural number, and i,j are positive integers.

11. A luminance compensation device of a display device, comprising:

an obtaining unit, configured to obtain an input grayscale value of a current sub-pixel, and obtain a functional relationship between a compensated grayscale value and the input grayscale value corresponding to the sub-pixel, for each of sub-pixels corresponding to the display device in an input image;

a compensating unit, configured to obtain the compensated grayscale value corresponding to the sub-pixel by using the input grayscale value of the sub-pixel and the functional relationship, and perform luminance compensation on the sub-pixel according to the compensated grayscale value, for each of the sub-pixels corresponding to the display device in the input image; and

a presetting unit, configured to;

determine a functional relationship between a test luminance value and a test grayscale value of each of the sub-pixels, according to a plurality of test grayscale values and a plurality of test luminance values under the plurality of test grayscale values for each of the sub-pixels of the display device;

wherein the presetting unit is further configured to;

select a part of grayscale values from among all of the grayscale values of the display device as the plurality of test scale values determine a plurality of test patterns according to the plurality of test a scale values selected and obtain the plurality of test luminance values by collecting the test luminance value under each of the plurality of test patterns by using an image sensor.

12. The luminance compensation device according to claim 11, wherein the presetting unit is further configured to:

determine a functional relationship between a target luminance value and the test grayscale value of the sub-pixel, according to the plurality of test grayscale values and target luminance values under the plurality of test grayscale values;

determine a grayscale compensation amount corresponding to each of the test grayscale values of each of the sub-pixels, according to the functional relationship between the test luminance value and the test grayscale value and the functional relationship between the target luminance value and the test grayscale value;

determine a functional relationship between the compensated grayscale value and the test grayscale value corresponding to the sub-pixel, according to the grayscale compensation amount corresponding to each of the test grayscale values of the sub-pixel, the functional relationship between the compensated grayscale value and the test grayscale value corresponding to the sub-pixel being just the functional relationship between the compensated grayscale value and the input grayscale value corresponding to the sub-pixel.

13. The luminance compensation device according to claim 11, wherein, the functional relationship between the compensated grayscale value and the input grayscale value corresponding to each of the sub-pixels complies with a formula below:

G_ij,x′

=C_ij,n G_xⁿ+C<sub>ij,n−

1</sub>G_x<sup>n−

1</sup>+ . . . +C_ij,1G_x+C_ij,0,

where, G_ij,x′

is a compensated grayscale value corresponding to a sub-pixel in i-th row and j-th column, G_x is an input grayscale value corresponding to the sub-pixel, C_ij,n is a coefficient of an n-th expansion item of G_x, n is a natural number, and i, j are positive integers.

14. A display device, comprising:

the luminance compensation device according to claim 11.

15. The display device according to claim 14, wherein the luminance compensation device is a control module of the display device.

16. The display device according to claim 14, wherein the presetting unit of the luminance compensation device is a processor disposed outside the display device.

17. The luminance compensation device according to claim 11, wherein the obtaining unit is configured to:

obtain the functional relationship from a volatile memory.

18. The luminance compensation device according to claim 17, wherein the obtaining unit is further configured to:

read the functional relationship corresponding to the current sub-pixel from a non-volatile memory to the volatile memory, before obtaining the functional relationship from the volatile memory.