Patent ID: 6839181

Claim:
A display apparatus comprising: (a) a light source for forming a beam of light; (b) illumination optics for shaping and directing said beam of light; (c) a splitter for splitting said beam of light into at least three color beams of light; (d) a modulation optical system for each of said three color beams of light, comprising: (1) a pre-polarizer for polarizing said beam of light to provide a polarized beam of light of a given color; (2) a wire grid polarization beamsplitter for receiving said polarized beam of light, for transmitting said polarized beam of light having a first polarization, and for reflecting said polarized beam of light having a second polarization orthogonal to said first polarization, wherein subwavelength wires on said wire grid polarization beamsplitter face a reflective spatial light modulator; (3) an imager field lens that provides nominally telecentric light to said reflective spatial light modulators (4) a reflective spatial light modulator wherein said reflective spatial light modulator receives said polarized beam of light, having either a first polarization or a second polarization, and selectively modulates said polarized beam of light to encode data thereon, providing both modulated light and unmodulated light which differ in polarization; (5) wherein said reflective spatial light modulator reflects back both said modulated light and said unmodulated light to said wire grid polarization beamsplitter, (6) wherein said wire grid polarization beamsplitter separates said modulated light from said unmodulated light; and (7) a polarization analyzer that receives said modulated light, and which further removes any residual unmodulated light from said modulated light; (8) an imaging relay lens in each color that provides an intermediate image of the reflective spatial light modulator from the modulated light for that color; (e) a dichroic combiner for re-combining the modulated light for each given color, such that the multiple color beams form the respective intermediate images along a common optical axis to form a combined intermediate image; and (f) a projection lens for imaging said combined intermediate image to a display screen.