Methods for calibrating correlation between voltage and grayscale value of display panels

1. A method for calibrating a plurality of voltages of a light-emitting element and a plurality of grayscale values of a respective pixel of the light-emitting element on a display panel, the pixel comprising the light-emitting element, comprising:

determining a mapping correlation between the plurality of voltages of the light-emitting element and a plurality of luminance values of the light-emitting element;

determining N grayscale values of the pixel, N being a positive integer and less than a number of the plurality of grayscale values;

determining N first luminance values each corresponding to the respective one of the N grayscale values;

determining N first voltages mapped to the N first luminance values using the mapping correlation;

determining, of each one of the N first luminance values, (M−1) second luminance values, each one of the (M−1) second luminance values corresponding to a different dimmed luminance value of the respective first luminance value, M being a positive integer;

determining, of each one of the N first luminance values, (M−1) second voltages mapped to the respective (M−1) second luminance values;

determining the plurality of voltages of the light-emitting element based on the N first voltages and (M−1)×N second voltages;

determining the plurality of grayscale values of the pixel based on the N grayscale values and (M−1)×N second luminance values; and

determining a correlation of the light-emitting element between the plurality of voltages and the plurality of grayscale values by mapping the plurality of voltages to the plurality of grayscale values.

2. The method of claim 1 , wherein determining a mapping correlation between the plurality of voltages of the light-emitting element and a plurality of luminance values of the light-emitting element comprises:

determining a plurality of target luminance values of a respective pixel of the light-emitting element;

determining a plurality of actual voltages of the light-emitting element in response to the pixel displaying the plurality of target luminance values; and

determining the mapping correlation based on the plurality of target luminance values and the plurality of actual voltages.

3. The method of claim 2 , wherein determining the plurality of target luminance values comprises determining at least 3 target luminance values.

4. The method of claim 3 , wherein determining the at least 3 target luminance values comprise determining a maximum luminance value of the pixel, and determining at least two different target luminance values less than the maximum luminance value.

5. The method of claim 4 , further comprising:

determining another mapping correlation between a plurality of other voltages and a plurality of other luminance values of another light-emitting element of the pixel, the light-emitting element and the other light-emitting element each displaying a different primary color;

determining, of the other light-emitting element, N first other voltages mapped to the N first luminance values using the other mapping correlation;

determining, of each one of the N first luminance values, (M−1) second other luminance values, each one of the (M−1) second other luminance values corresponding to a different dimmed luminance value of the respective first luminance value;

determining, of the other light-emitting element, (M−1) second other voltages mapped to the respective (M−1) second other luminance values for each one of the N first luminance values;

determining the plurality of other voltages of the other light-emitting element based on the N first other voltages and (M−1)×N second other voltages;

determining a plurality of other grayscale values of the pixel based on the N grayscale values and (M−1)×N second luminance values; and

determining a correlation between, of the other light-emitting element, the plurality of other voltages and the plurality of other grayscale values by mapping the plurality of other voltages to the plurality of other grayscale values.

6. The method of claim 2 , further comprising maintaining a target color temperature of the pixel when the plurality of target luminance values are displayed by the pixel.

7. The method of claim 2 , wherein determining the plurality of actual voltages of the light-emitting element in response to a pixel of the light-emitting element displaying the plurality of target luminance values comprises measuring and storing the plurality of actual voltages of the light-emitting element from a display panel.

8. The method of claim 2 , wherein the mapping correlation comprises a polynomial with a degree of at least 2, each one of the plurality of luminance values varying as a function of a respective one of the plurality of voltages following the polynomial.

9. The method of claim 2 , wherein determining the plurality of actual voltages of the light-emitting element in response to the pixel displaying the plurality of target luminance values comprises:

adjusting a current of the light-emitting element so the respective pixel of the light-emitting element displays the plurality of target luminance values; and

measuring and storing values of the plurality of actual voltages corresponding to the current in response to the respective pixel displaying the plurality of target luminance values.

10. The method of claim 2 , further comprising storing the correlation of the light-emitting element between the plurality of voltages and the plurality of grayscale values in a register and employing the correlation as a lookup table to calibrate the grayscale values in a Gamma correction process.

11. The method of claim 1 , wherein determining the N first luminance values each corresponding to the respective one of the N grayscale values comprising performing a power-law operation on the N grayscale values to obtain the N first luminance values.

12. The method of claim 11 , wherein determining the plurality of voltages of the light-emitting element based on the N first voltages and (M−1)×N second voltages and determining the plurality of grayscale values of the pixel based on the N grayscale values and (M−1)×N second luminance values comprises:

performing an interpolation operation on the N first voltages and the (M−1)×N second voltages to obtain the plurality of voltages;

performing an inverse operation of the power-law operation on the (M−1)×N second luminance values to obtain (M−1)×N second grayscale values; and

performing another interpolation operation on the N grayscale values and the (M−1)×N second grayscale values to obtain the plurality of grayscale values.

13. A method for calibrating voltages of a light-emitting element and luminance values of a respective pixel on a display panel, comprising:

determining a plurality of target luminance values and a target color temperature of a respective pixel;

determining a plurality of actual voltages of the light-emitting element in response to the pixel displaying the plurality of target luminance values; and

determining a mapping correlation between the voltages and luminance values of the light-emitting element based on the plurality of target luminance values and the plurality of actual voltages.

14. The method of claim 13 , wherein determining the plurality of target luminance values comprises determining at least 3 target luminance values.

15. The method of claim 14 , wherein determining the at least 3 target luminance values comprise determining a maximum luminance value of the pixel, and determining at least two different target luminance values less than the maximum luminance value.

16. The method of claim 13 , further comprising maintaining the target color temperature of the pixel when the plurality of target luminance values are displayed by the pixel.

17. The method of claim 13 , wherein determining the plurality of actual voltages of the light-emitting element in response to a pixel of the light-emitting element displaying the plurality of target luminance values comprises measuring and storing the plurality of actual voltages of the light-emitting element from a display panel the light-emitting element is located in.

18. The method of claim 13 , wherein the mapping correlation comprises a polynomial with a degree of at least 2, each one of the plurality of target luminance values varying as a function of the plurality of actual voltages following the polynomial.

19. The method of claim 13 , further comprising:

determining a plurality of other actual voltages of another light-emitting element in response to the pixel displaying the plurality of target luminance values; and

determining another mapping correlation based on the plurality of target luminance values and the plurality of other actual voltages.

20. A system for calibrating a plurality of voltages of a light-emitting element and a plurality of grayscale values of a respective pixel on a display panel, the pixel comprising the light-emitting element, comprising:

a display having the pixel; and

a processor, comprising:

a grayscale-luminance converting sub-module configured to determine N first luminance values each corresponding to the respective one of N grayscale values of the pixel;

a luminance-voltage correlation analyzing sub-module configured to determine a mapping correlation between a voltage of the light-emitting element and a luminance value of the light-emitting element;

a grayscale-voltage mapping sub-module configured to determine N first voltages mapped to the N first luminance values using the mapping correlation;

a luminance-voltage mapping sub-module configured to determining, for each one of the N first luminance values, (M−1) second luminance values and (M−1) second voltages mapped to the respective (M−1) second luminance values, each one of the (M−1) second luminance values corresponding to a different dimmed luminance value of the respective first luminance value, M being a positive integer, and an interpolating sub-module configured to:

determine the plurality of voltages of the light-emitting element based on the N first voltages and (M−1)×N second voltages;

determine the plurality of grayscale values of the pixel based on the N grayscale values and (M−1)×N second luminance values; and

determine a correlation of the light-emitting element between the plurality of voltages and the plurality of grayscale values by mapping the plurality of voltages to the plurality of grayscale values.

21. The system of claim 20 , wherein the luminance-voltage correlation analyzing module is configured to:

determine a plurality of target luminance values of a respective pixel of the light-emitting element;

determine a plurality of actual voltages of the light-emitting element in response to the pixel displaying the plurality of target luminance values; and

determine the mapping correlation based on the plurality of target luminance values and the plurality of actual voltages.

22. The system of claim 21 , wherein the plurality of target luminance values comprises at least 3 target luminance values.

23. The system of claim 22 , wherein the at least 3 target luminance values comprise a maximum luminance value of the pixel and at least two different target luminance values less than the maximum luminance value.

24. The system of claim 21 , wherein the luminance-voltage correlation analyzing module is further configured to maintain a target color temperature of the pixel when the plurality of target luminance values are displayed by the pixel.

25. The system of claim 24 , wherein:

the mapping correlation comprises a polynomial with a degree of at least 2, each one of the plurality of target luminance values varying as a function of the plurality of actual voltages following the polynomial; and

the N first luminance values are correlated to the respective N grayscale values by an inversion of a power-law operation.