Optical layout for a three light valve full-color projector employing a dual relay lens system and a single projection lens

Claim 1

A liquid crystal light valve image projection system comprising: (a) an illumination source for providing unpolarized white light; (b) polarizing means disposed in the path of said unpolarized light, said polarizing means including a prepolarizer for transmitting light of a first polarization and reflecting light of a second polarization away from the optical path of the transmitted light of said first polarization, said polarizing means further including a polarizer/analyzer for reflecting light of said first polarization and transmitting light of said second polarization, said polarizer/analyzer being disposed in the optical path of the transmitted light from said prepolarizer; (c) relay lens means for relaying images along the optical path of said image projection system; (d) projection optics for projecting image data; and (e) light valve means disposed in the optical path of the polarized light that is reflected by said polarizer/analyzer, said light valve means modulating the polarization state of the light reflected by said polarizer analyzer and reflecting polarization-modulated light back along the optical path of the polarized light that is reflected by said polarizer/analyzer, said polarization-modulated light that is reflected by said light valve being being passed by said polarization/analyzer to said projection optics.