OVERDRIVE METHOD OF FOUR-COLOR PANEL

• US 20190005900A1
• Filed: 01/18/2017
• Published: 01/03/2019
• Est. Priority Date: 08/31/2016
• Status: Active Grant

• Current Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Shenzhen China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: Chen, Lixuan
• Granted Patent: US 10,360,860 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/13 based on liquid crystals, e.g. single liquid crystal display cells
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/0257 Reduction of after-image effects
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/36 using liquid crystals
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127

Abstract

An overdrive method of a four-color panel is disclosed. The method comprises searching 10% brightness value point and 90% brightness value point in a normalized curve, calculating difference between R (or B) brightness normalized curve and G brightness normalized curve ranging from 10% brightness value point to 90% brightness value point, and determining each RIG overdrive gray-scale voltage value in an overdrive gray-scale voltage table through evaluating a minimum value of the difference between brightness normalized curves. The obtained changed R/G/B overdrive target values are substituted into a formula for calculating W overdrive target value between different gray-scales.

Claims

1. An overdrive method of a four-color panel, comprising steps of:

step 1, calculating R/G/B overdrive target values, wherein R is a red sub-pixel, G is a green sub-pixel, and B is a blue sub-pixel;

step 2, obtaining R/G/B overdrive target values between different gray-scales according to switching waveforms between different gray-scales;

step 3, calculating a W overdrive target value according to the R/G/B overdrive target values obtained in step 1, wherein W is a white sub-pixel;

step 4, obtaining W overdrive target values between different gray-scales according to the R/G/B overdrive target values between different gray-scales obtained in step 2 and a first formula, which is;

2. The method according to claim 1, wherein the calculating R/G/B overdrive target values in step 1 comprises sub steps of:

step 11, performing dynamic switching among four frames, which includes a first to a fourth frames, according to a starting gray-scale and an ending gray-scale of a selected chart of an overdrive table to be completed;

step 12, trying an overdrive target value in order to obtain an R/G/B brightness-response time curve corresponding to the overdrive target value;

step 13, subjecting the R/G/B brightness-response time curve obtained in step 12 to a noise reduction and smoothening treatment;

step 14, taking a brightness value of the third frame of step 11 as target brightness and determining whether the R/G/B brightness-response time curve obtained according to the overdrive target value of the trial shows brightness that matches the target brightness and if yes, going to step 15, otherwise repeating steps 12-14;

step 15, if the brightness of the R/G/B brightness-response time curve corresponding to the overdrive target value of the trial is the first brightness that matches the target brightness, filling the overdrive target value of the trail in a corresponding position in the overdrive table to be completed and repeating steps 12-14; and

if the brightness of the R/G/B brightness-response time curve corresponding to the overdrive target value of the trial is not first brightness that matches the target brightness, comparing response time of the R/G/B brightness-response time curve obtained according to the overdrive target value of the trial to response time of the R/G/B brightness-response time curve obtained according to an overdrive target value set in a corresponding position in the overdrive table to be completed and going to step 16;

step 16, if the response time of the R/G/B brightness-response time curve obtained according to the overdrive target value of the trial is less than the response time of the R/G/B brightness-response time curve obtained according to the overdrive target value set in the corresponding position in the overdrive table to be completed, replacing the overdrive target value of the corresponding position in the overdrive table to be completed with the overdrive target value of the trial and repeating steps 12-15;

if the response time of the R/G/B brightness-response time curve obtained according to the overdrive target value of the trial is greater than the response time of the R/G/B brightness-response time curve obtained according to the overdrive target value set in the corresponding position in the overdrive table to be completed, setting the overdrive target value of the corresponding position in the overdrive table to be completed to be finally determined overdrive target value and going to step 17; and

step 17, repeating steps 11-16 until calculation of all overdrive target values of the overdrive table are completed.

3. The method according to claim 2, wherein based on sequence of repeating, the overdrive target values are tried in step 12 in a sequence from a smallest one to a largest one.

4. The method according to claim 2, wherein based on sequence of repeating, the overdrive target values are tried in step 12 in a sequence from a largest one to a smallest one.

5. The method according to claim 3, wherein in step 13, a median filter is used to perform noise reduction and smoothening treatment on the R/G/B brightness-response time curve obtained in step 12.

6. The method according to claim 4, wherein in step 13, a median filter is used to perform noise reduction and smoothening treatment on the R/G/B brightness-response time curve obtained in step 12.

7. The method according to claim 1, wherein in step 2. of obtaining R/G/B overdrive target values between different gray-scales, three-color signals R/G/B are input, and four-color signals R/G/B/W are output in a mapping state.

8. The method according to claim 2, wherein in step 2 of obtaining R/G/B overdrive target values between different gray-scales, three-color signals R/G/B are input, and four-color signals R/G/B/W are output in a mapping state.

9. The method according to claim 3, wherein in step 2 of obtaining R/G/B overdrive target values between different gray-scales, three-color signals R/G/B are input, and four-color signals R/G/B/W are output in a mapping state.

10. The method according to claim 4, wherein in step 2 of obtaining R/G/B overdrive target values between different gray-scales, three-color signals R/G/B are input, and four-color signals R/G/B/W are output in a mapping state.

11. The method according to claim 5, wherein in step 2 of obtaining R/G/B overdrive target values between different gray-scales, three-color signals R/G/B are input, and four-color signals R/G/B/W are output in a mapping state.

12. The method according to claim 6, wherein in step 2 of obtaining R/G/B overdrive target values between different gray-scales, three-color signals R/G/B are input, and four-color signals R/G/B/W are output in a mapping state.

13. The method according to claim 7, wherein calculation of the W overdrive target value in step 3 is performed in a mapping state.

14. The method according to claim 8, wherein calculation of the W overdrive target value in step 3 is performed in a mapping state.

15. The method according to claim 9, wherein calculation of the W overdrive target value in step 3 is performed in a mapping state.

16. The method according to claim 10, wherein calculation of the overdrive target value in step 3 is performed in a mapping state.

17. The method according to claim 12, wherein calculation of the W overdrive target value in step 3 is performed in a mapping state.

18. The method according to claim 17, wherein the overdrive table in step 5 is a 17*17 overdrive table.

19. The method according to claim 18, wherein step 5 of adding calculation of difference of brightness normalized curves to calculation of an R/G/B overdrive table to obtain changed R/G/B overdrive target values comprises sub steps of:

step 51, searching 10% brightness value point and 90% brightness value point in a normalized curve; and

step 52, calculating difference between R (or B) brightness normalized curve and G brightness normalized curve ranging from 10% brightness value point to 90% brightness value point thereof;

deltaL=(Lv(R)−

Lv(G))̂

2,

wherein Lv(R) is R brightness, Lv(G) is G brightness, and each R/G overdrive gray-scale voltage value in an overdrive gray-scale voltage table is determined through evaluating a minimum value of the difference between brightness normalized curves.

20. The method according to claim 19, wherein the factor in step 6 fluctuates around integer 1.