Optimize Maximal Brightness and Correlated Color Temperature for Multi-primary color displays

Abstract

Color temperature(CT) conversion of triprimary color display from one white point to another on the Planckian's locus with the maximal brightness has been proposed. However, whether converting an original white point to another white point on the isotemperature line will enlarge maximal brightness more than converting an original white point to another white point on the Planckian's locus needs to be determined. This paper proposes a new algorithm to enlarge maximal brightness by calling the center of gravity method of color mixing in the acceptable color difference range while the CT is converted. From the prior study, we find that the apexes of color gamut boundary move along the line of center gravity of primaries while the total brightness varies, where the line of center gravity of primaries is linked by the color points mixed by two or more full primary colors and one partial primary color. And in CIE 1931 color space, the color gamut boundary expanding from white point as total brightness decreasing will touch the isotemperature line with its apexes. Therefore, the best point of CT conversion of tri-primary color display with more maximal brightness is determined by the isotemperature line and the line of center gravity of primaries. Further, the theory extends to multi-primary color displays. Lastly, the simulations prove that converting a white point to another on the isotemperature line enlarges maximal brightness more than converting a white point to another on Planck's locus.