Patent ID: 8040589

Claim:
An illumination apparatus comprising: a light guide that guides light propagating therein at an angle greater than a critical angle for the light guide and ejects light from the light guide to provide illumination; diffractive microstructure disposed to receive an ambient light at a first angle smaller than said critical angle and to diffract said ambient light to produce diffracted light at a second larger angle, such that said diffracted light propagates through the light guide; and light-turning features configured to turn the diffracted light and direct the turned light out of the light guide, wherein the light guide, the diffractive microstructure, and the light-turning features are disposed with respect to a spatial light modulator such that light ejected from the light guide illuminates said spatial light modulator, wherein said spatial light modulator comprises a MEMS device, wherein said MEMS device comprises interferometric modulators, wherein said MEMS device comprises first and second reflective surfaces, one of which is movable with respect to the other.