[OPTICAL REVIEW Vol. 8, No. 3 (2001) 191-197]
Color Conversion Method for Multiprimary Display Using Matrix Switching
Takeyuki AJITO1,2, Kenro OHSAWA2, Takashi OBI1,2, Masahiro YAMAGUCHI1,2,* and Nagaaki OHYAMA1,2
1Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259, Nagatsuta, Midori-ku, Yokohama, 226-8503 Japan, 2Akasaka Natural Vision Research Center, Telecommunications Advancement Organization of Japan, 1-8-6, Akasaka, Minato-ku, Tokyo, 107-0052 Japan
(Received December 13, 2001; Accepted March 23, 2001)
The range of reproducible color, i.e., color gamut, of conventional three-primary display devices is sometimes insufficient for reproducing the natural color of an object through color imaging systems. A multiprimary display is being developed for the purpose of reproducing an expanded color gamut using more than three primary colors. In this paper, a color conversion method is proposed to reproduce the natural color by additive mixture of multiprimary colors. The multiprimary color signal in this conversion method is calculated from the three-dimensional color coordinates CIE-XYZ, considering the dynamic range of each primary color. Divided into some linear elements from the polyhedral color solid of the multiprimary display, the conversion considering the constraint of the dynamic range can be performed by simple calculation without iterative calculation or a huge three-dimensional look up table. A fast computation method with a two-dimensional look-up-table is also presented. Using the proposed method, the result of the color reproduction is experimentally demonstrated by a six-primary projection display.
Key words : color reproduction, color gamut, primary color, color conversion