Method for obtaining primary color values of display device and method for establishing color correction tables of same
An exemplary method for obtaining primary color values via measuring color values of a display device, the method including: measuring tristimulus values when the display device respectively displaying a red, green, and blue monochromatic patterns, the red, green, and blue monochromatic patterns respectively having the largest intensity; measuring tristimulus values when the display device displaying a white pattern mixed by the red, green, and blue colors; calculating intensity values of the red, green, and blue colors of the white pattern.
1 . A method for obtaining primary color values via measuring color values of a display device, the method comprising:
measuring tristimulus values when the display device respectively displaying a red, green, and blue monochromatic patterns, the red, green, and blue monochromatic patterns respectively having the largest intensity;
measuring tristimulus values when the display device displaying a white pattern mixed by the red, green, and blue colors;
calculating intensity values of the red, green, and blue colors of the white pattern.
2 . The method as claimed in claim 1 , wherein the tristimulus values are measured in the XYZ color space.
3 . The method as claimed in claim 2 , wherein the intensity values of the red, green, and blue colors of the white pattern are calculated by the following equation:
[
Lri
Lgi
Lbi
]
=
[
Xr
Xg
Xb
Yr
Yg
Yb
Zr
Zg
Zb
]
-
1
*
[
Xi
Yi
Zi
]
*
[
Yr
Yg
Tb
]
,
where Xr, Yr, Zr, Xg, Yg, Zg, and Xb, Yb, Zb respectively represent the tristimulus values of the red, green, and blue monochromatic patterns, Xi, Yi, Zi represent the tristimulus values of the white pattern, Lri, Lgi, Lbi represent the intensity values of the red, green, and blue primary colors of the white pattern.
4 . A method for establishing color correction tables, the method comprising:
providing a display device, a signal generator, and a color analyzer;
initializing the display device, the signal generator, and the color analyzer;
measuring tristimulus values when the display device respectively displaying a red, green, and blue monochromatic patterns, the red, green, and blue monochromatic patterns respectively having the largest intensity;
measuring tristimulus values when the display device displaying 2 n white patterns corresponding to 2 n different gray levels, each of the white patterns being mixed by red, green, and blue primary colors;
calculating intensity values of the red, green, and blue primary colors of the 2 n white patterns, respectively;
obtaining color correction curves of red, green, and blue primary colors by arithmetic interpolating among the gray levels of the 2 n white patterns;
obtaining ideal color correction curves of red, green, and blue primary colors, respectively;
storing 256 gray levels on the color correction curves of the red, green, and blue colors respectively, the 256 gray levels having intensity values that are closest to the intensity values of the gray level 0 through the gray level 255 on the corresponding ideal color correction curves;
establishing the red color correction table, the green color correction table, and the blue color correction table, respectively;
establishing the color correction tables of the display device.
5 . The method as claimed in claim 4 , wherein if the display device comprises predetermined color correction tables, invalidates the predetermined color correction function of the display device before initializing the display device, the signal generator, and the color analyzer.
6 . The method as claimed in claim 4 , wherein the tristimulus values are measured via the color analyzer in the XYZ color space.
7 . The method as claimed in claim 4 , wherein the display device displays 64 white patterns corresponding to the 0 th , the 4 th , the 8 th , . . . , the 248 th , and the 252 nd gray levels, the color analyzer measures the tristimulus values of the 64 white patterns, respectively.
8 . The method as claimed in claim 4 , wherein the intensity values of the red, green, and blue primary colors of the white pattern are calculated by the following equation:
[
Lri
Lgi
Lbi
]
=
[
Xr
Xg
Xb
Yr
Yg
Yb
Zr
Zg
Zb
]
-
1
*
[
Xi
Yi
Zi
]
*
[
Yr
Yg
Tb
]
,
where Xr, Yr, Zr, Xg, Yg, Zg, and Xb, Yb, Zb respectively represent the tristimulus values of the red, green, and blue monochromatic patterns, Xi, Yi, Zi represent the tristimulus values of the white pattern, Lri, Lgi, Lbi represent the intensity values of the red, green, and blue primary colors of the white pattern.
9 . The method as claimed in claim 4 , wherein the red, green, and blue color correction curves are respectively obtained by an arithmetic method of Bezier interpolation.
10 . The method as claimed in claim 9 , wherein the Bezier interpolation is performed by equally dividing each part of a bezier curve that between two adjacent gray levels, the two adjacent gray levels corresponds to two of the 2 n white patterns.
11 . The method as claimed in claim 10 , wherein the bezier curve is equally divided in the gray level direction.
12 . The method as claimed in claim 10 , wherein each part of the bezier curve is divided into 16 equal parts.
13 . The method as claimed in claim 4 , wherein the red, green, and blue color correction curves are respectively obtained by an arithmetic method of linear interpolation.
14 . The method as claimed in claim 4 , wherein the ideal color correction curves of red, green, and blue primary colors are respectively obtained by the following equation:
Ln =( L max− L min)( n/ 255)̂gamma+ L min,
Where Lmax represents the largest intensity value of corresponding monochromatic pattern displayed by the display device, Lmin represents the smallest intensity value of the corresponding monochromatic pattern displayed by the display device, the variable n is a whole number in the range from 0 to 255 representing the number of gray levels, Ln represents an intensity value of the monochromatic pattern corresponding to the n th gray level, gamma is a constant, which is equal to 2.2.
15 . The method as claimed in claim 4 , wherein the ideal color correction curves of red color is obtained by the following equation:
L total= Lr 255+ Lg 255+ Lg 255= Lw 255,
Kr 255= Lr 255/ L total,
Lrn=Kr 255* Lwn
where Lr255, Lg255, Lg255 represent the largest intensities when the display device respectively display red, green, and blue monochromatic patterns, Lw255 represents the intensity value of a white pattern mixed by the red, green, and blue primary colors that respectively have the largest intensity values, Kr255 represents percentage values of the intensity of the red color in the white pattern, Lrn represent an intensity value of the red color in a white pattern corresponding to the n th gray level, Lwn represents a measured intensity value of the white pattern corresponding to the n th gray level.
16 . The method as claimed in claim 14 , wherein percentage values of the intensities of the red, green and blue primary colors in different white patterns are constant.