Patent ID: 6900866
Filing Date: 2005-05-31
Classification: G02B,G02F,H04N

Abstract:
1. A modulation optical system for providing modulation of an incident light beam comprising: (a) a wire grid polarization beamsplitter for receiving said beam of light, for transmitting light of said beam of light having a first polarization, and for reflecting light of said beam of light having a second polarization orthogonal to said first polarization, wherein sub-wavelength wires on said wire grid polarization beamsplitter face a reflective spatial light modulator; (b) 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; (c) wherein said reflective spatial light modulator reflects back both said modulated light and said unmodulated light to said wire grid polarization beamsplitter; (d) wherein said wire grid polarization beamsplitter separates said modulated light from said unmodulated light; (e) a compensator is located between said wire grid polarization beamsplitter and said reflective spatial light modulator, wherein said compensator is provided for conditioning the polarization states of the oblique and skew rays of said modulated beam; and wherein said compensator has a spatially variant retardance that corrects for a spatially variant retardance of said reflective spatial light modulator.