Patent ID: 7686455

Claim:
An optical system comprising: a modulation optical system for combining respective modulated primary color lights with each other in wavelength thereby to produce and output a first composite light, the respective modulated primary color lights being provided by modulating 3-primary color lights by 3-primary color signals produced from an image signal individually, a color spectroscope for transmitting and reflecting the first composite light thereby to divide it into a second composite light composed of a plurality of first primary color components each having a wavelength bandwidth narrower than that of the respective primary colors' lights, and a third composite light composed of a plurality of second primary color components each having a wavelength bandwidth narrower than that of the respective primary colors' lights and different from each of the wavelength bandwidths of the first primary color components; a modulator for modulating the second composite light by one of two kinds of luminance signals produced from the image signal thereby to produce a first modulation light and modulating the third composite light by the other of the luminance signals thereby to produce a second modulation light; a photosynthesizer for combining the first modulation light with the second modulation light thereby to produce a fourth composite light; and a projector for projecting the fourth composite light.