White balance adjusting method

A white balance adjusting method, comprising steps of:

• A. obtaining maximum spectral tristimulus values Xmax, Ymax and Zmax in CIE1931 chromaticity coordinate system for a panel to be tested, minimum spectral tristimulus values X0, Y0 and Z0 in CIE1931 chromaticity coordinate system for the panel to be tested, spectral tristimulus values RXm, RYm, RZm of respective gray levels of a red color for the panel to be tested, spectral tristimulus values GXm, GYm, GZm of the respective gray levels of a green color for the panel to be tested, and spectral tristimulus values BXm, BYm, BZm of the respective gray levels of a blue color for the panel to be tested, where m is a gray level number, X, Y, Z are the spectral tristimulus values of the panel to be tested;
• B. converting the maximum spectral tristimulus values Xmax, Ymax and Zmax into maximum color stimulus values Lmax, amax and bmax in CIE1931 chromaticity coordinate system according to a conversion formula of CIE1931 chromaticity coordinate system, where L is a psychological lightness, a, b indicate a psychological chroma;
• C. converting the maximum color stimulus values Lmax, amax and bmax into a hue H and a chroma C of the panel to be tested;
• D. computing spectral stimulus values Y1 to Ymax-1 for intermediate gray levels according to brightness variance matching gray level index variance and based on Ymax and Y0;
• E. computing spectral stimulus values X1 to Xmax-1 and Z1 to Zmax-1 for the intermediate gray levels according to the hue H, the chroma C and the spectral stimulus values Y1 to Ymax-1 of the respective gray levels;
• F. determining spectral tristimulus values of the three colors red, green and blue of a white field of the respective gray levels for the panel to be tested according to the spectral tristimulus values X0 to Xmax, Y0 to Ymax and Z0 to Zmax of the respective gray levels, and further obtaining gray level numbers of the three colors red, green and blue in the white field of the respective gray levels;
• the step B particularly comprising converting the maximum spectral tristimulus values Xmax, Ymax and Zmax into the maximum color stimulus values Lmax, amax and bmax in CIE1976 chromaticity coordinate system according to the following formula:
• Lmax=116*f(Ymax/Ys)−16,
• amax=500*[f(Xmax/Xs)−f(Ymax/Ys)].
• bmax=200*[f(Ymax/Ys)−f(Zmax/Zs)],
• where Xs, Ys, Zs are spectral tristimulus values of a CIE standard illuminant, L is the psychological lightness, a, b indicate the psychological chroma;
• the step E particularly comprising converting the hue H, the chroma C and the spectral stimulus values Y1 to Ymax-1 of the respective gray levels into the spectral stimulus values X1 to Xmax-1 and Z1 to Zmax-1 of the respective gray levels according to the following formula:
• f(Xn/Xs)−f(Yn/Ys)=f(Xmax/Xs)−f(Ymax/Ys),
• f(Yn/Ys)−f(Zn/Zs)=f(Ymax/Ys)−f(Zmax/Zs),
• f(Xn-1/Xs)−f(Yn-1/Ys)=f(Xn/Xs)−f(Yn/Ys),
• f(Yn-1/Ys)−f(Zn-1/Zs)=f(Yn/Ys)−f(Zn/Zs);
• where a range of n is 0˜max, Xs, Ys, Zs are the spectral tristimulus values of the CIE standard illuminant;
• the spectral tristimulus values of the CIE standard illuminant Xs=Ys=Zs=100.