Colorful as they are, today's television and computer screens generate only about half the hues of the visible-light spectrum. Now, experimenters in Switzerland have found a way to provide the complete color palette. To do so, they use a material called artificial muscle because it changes length in response to electricity (SN: 7/1/06, p. 8: Pumping Alloy).
In conventional displays, three light emitters—one red, one green, and one blue—make up each pixel. Varying their relative intensities yields composite colors such as orange. The three fixed hues can't combine to yield every color.