Why do CRTs Use Red, Green, and Blue rather than Red, Yellow, Blue?
So you were taught in grade school that any color could be made up of red, yellow, and blue paint. Why are these not used in CRTs? Nearly any color that we can perceive can be made from some combination of primary colors. There are two types – additive and subtractive. RGB are primary additive colors – anything that emits light will use these. The three types of cone (color) recepters in the retina of the human eye have peaks (roughly) sensitive to these primary colors. Those red, yellow, and blue primaries you used to create your works of art should actually not have been red, yellow, blue but rather magenta, yellow, cyan – close but no cigar. Red, yellow, and blue are approximations good enough for basic painting or printing but are not capable of reproducing the widest range of colors. CMY (cyan, magenta, yellow) are subtractive colors. Printing processes and color photography use these because layers of ink or dye absorb light. Basically, each of CMY removes a single color from (RG
