<title>Getting more for less: a new opponent color technique for two-channel color displays</title>

Abstract

A new technique is described for making color liquid crystal displays with only two color channels. Red and white channels were tried first, expanding upon the photographic approach of Edwin Land. A test image simulating the liquid crystal display was produced on a standard color cathode ray tube. With shades of red and white arranged in alternating diagonals of a checkerboard pattern, observers saw more colors than predicted by simple color mixtures of red and white — for example green was seen by all observers. But why white and red channels? One brightness and one color opponent channel (one which switches between opposing colors such as red and cyan) better describes the major two components in the color vision system. A test image with one white channel and one opponent red/blue channel in a checkerboard pattern gave rise to an even wider range of colors than did the Land-type display. Photographic print and slide film versions of the displays also showed the effects. In the liquid crystal display, the opposing colors can be produced by using a dichroic polarizer. Such two-channel displays have the advantages of higher spatial resolution or lower cost than conventional color displays. A prototype liquid-crystal two-channel display should be developed.