Method for regulating common voltage, regulating device and display device

Patent metadata

Field	Value
Publication number	US-9953610-B2
Application number	US-201615085015-A
Country	US
Kind code	B2
Filing date	Mar 30, 2016
Priority date	Apr 8, 2015
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A method for regulating a common voltage, a regulating device and a display device. It relates to the display field, which ensures the flicker in the center region of the display panel being relative small meanwhile improving the flicker situation of the edge region of the display panel, thereby improve the flicker uniformity of the display panel. The present disclosure provides a method for regulating a common voltage including: arranging sampling points which at least include: sampling points arranged in the center region of the display panel and sampling points arranged in the edge region of the display panel; optimizing the common voltage value written into the driving chip, such that the flicker values of the sampling points located in the display panel are less than or equal to a first threshold when the common voltage value is applied to the display panel for display.

First claim

What is claimed is:

1. A method for regulating a common voltage of a display panel, comprising:
arranging at least one sampling point located in a center region of the display panel and at least one sampling point located in an edge region of the display panel;
optimizing the common voltage value to be written into a driving chip, such that flicker values of all the sampling points located in the display panel are less than or equal to a first threshold when the common voltage value is applied to the display panel for display;
wherein in a case in which the flicker values of all the sampling points located in the display panel are less than or equal to the first threshold, the common voltage value, which allows the flicker value of the at least one sampling point located in the center region of the display panel to be minimized, is selected as the common voltage value to be written into said driving chip.

2. The method according to claim 1 , wherein, the common voltage value to be written into the driving chip is optimized, such that the flicker value of the at least one sampling point located in the center region of the display panel is minimized in condition that the flicker values of all of the sampling points are less than or equal to the first threshold, when the common voltage value is applied to the display panel for display.

3. The method according to claim 2 , wherein, optimizing the common voltage value to be written into to the driving chip further comprises:
for each of the sample points, setting a plurality of test values for the common voltage sequentially, and measuring the flicker values of each of the sampling points corresponding to the plurality of test values;
for each of the sampling points, fitting a function relational expression of a flicker value of the sampling point with respect to the common voltage according to the measured flicker values of each of the sampling points;
determining a value range of the common voltage which meets a first condition by using said function relational expression, wherein said first condition represents that the flicker values of all of the sampling points are less than or equal to the first threshold;
selecting within said value range of the common voltage, the common voltage value, which allows the flicker value of the at least one sampling point located in the center region of the display panel to be minimized as the common voltage value to be written into said driving chip.

4. The method according to claim 3 , wherein, determining the value range of the common voltage which meets the first condition by using said function relational expression further comprises steps:
S 101 , figuring out a solution which allows a value of the function relational expression corresponding to each of the sampling points being less than or equal to a first value, wherein said first value is greater than 0 and less than or equal to said first threshold;
S 102 , if the solution of step S 101 exists, terminating the process and taking the solution as the value range of the common voltage which meets the first condition, if the solution of S 101 does not exist, circulating step S 103 through step S 105 , until the value range of said common voltage is determined or the value of said flicker value is greater than said first threshold;
S 103 , providing a value of the flicker value for a present solution, wherein said value of the flicker value for the present solution is a sum of a value of the flicker value for a previous solution and a preset step, said preset step being 1/K of said first threshold, K≥30;
S 104 , determining whether the value of the flicker value for the present solution is less than or equal to said first threshold, if a result of determination is positive, then proceeding with step S 105 , else, terminating the circulation process;
S 105 , figuring out a solution which allows the function relational expression corresponding to each of the sampling points being less than or equal to the value of said flicker value, if there is solution, terminating the circulation process and taking the solution as the value range of the common voltage which meets the first condition, else, proceeding with step S 103 .

5. The method according to claim 3 , wherein, determining the value range of the common voltage which meets the first condition by using said function relational expression further comprises:
S 201 , presetting n values for the flicker value: P 1 <P 2 <P 3 < . . . <P n , wherein, n is natural number other than 0, and P n is less than the first threshold;
S 202 , performing a calculation for each of the values of said flicker value according to ascending order as follows: figuring out a solution which allows the value of the function relational expression corresponding to each of the sampling points being less than or equal to the value of said flicker value, if there is a solution, terminating the calculation and taking the solution as the value range of the common voltage meets the first condition, else, repeating step S 202 , until the value ranges of said common voltage is determined or the −n values for the flicker complete the above operation;
S 203 , figuring out a solution which allows the value of the function relational expression corresponding to each of the sampling points being less than or equal to the value of said first threshold, if there is a solution, terminating the process and taking the solution as the value range of the common voltage which meets the first condition, else, terminating the process and taking the display panel as a unqualified product.

6. The method according to claim 5 , wherein, said n value for flicker value are more than or equal to one third of said first threshold, and less than or equal to two thirds of said first threshold.

7. The method according to claim 6 , wherein, n=3.

8. The method according to claim 3 , wherein, said function relational expression is a piecewise linearity function expression or a quadratic function expression.

9. The method according to claim 1 , wherein, one sampling point is located in the center region of said display panel, and four sampling points are located in the edge region of said display panel and are located at four corner regions of said display panel, respectively.

10. A common voltage regulating device for a display panel, which configured to optimize a common voltage value to written into a driving chip, such that flicker values of all the sampling points in the display panel are less than or equal to a first threshold when the common voltage value is applied to the display panel for display, wherein said sampling points comprises at least one sampling point located in a center region of said display panel and at least one sampling point located in an edge region of said display panel;
wherein in a case in which the flicker values of all the sampling points located in the display panel are less than or equal to the first threshold, the common voltage value, which allows the flicker value of the at least one sampling point located in the center region of the display panel to be minimized, is selected as the common voltage value to be written into said driving chip.

11. The common voltage regulating device according to claim 10 , wherein, said common voltage regulating device comprises comprising:
a screen illuminating unit backlight configured to illuminate the display panel and allow the display panel to operate under a flicker pattern;
a common voltage regulating circuit configured to set a plurality of test values for the common voltage of said display panel sequentially for each of the sampling points;
a photoelectric sensor configured to measur

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Optoelectronics Tech Co Ltd

Inventors

• Ding Jinbo
• Wang Jing
• Li Xin
• Zhang Ying
• Zhu Hong
• Yu Hongjun

Classifications

• G09G2320/0247

  Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes · CPC title

• G09G3/006

  Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309) · CPC title

• G09G3/3696 Primary

  Generation of voltages supplied to electrode drivers · CPC title

• G09G3/20

  for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix {no fixed position being assigned to or needed to be assigned to the individual characters or partial characters} · CPC title

• G09G3/3648

  using an active matrix (G09G3/367 - G09G3/3696 take precedence) · CPC title