Patent ID: 8565560

Claim:
An optical device comprising: at least one ESBG element sandwiched between transparent substrates, said ESBG element comprising a multiplicity of ESBG pixels disposed in a layer; transparent conductive coatings applied to each said substrate, at least one of said coatings being patterned into independently addressable elements overlapping said pixels; an electrical control circuit operative to apply voltages across each said pixel; and a light coupling element disposed adjacent to one of said substrates for diverting input light from an external light source into a total internal reflection path within said substrates, wherein each said pixel is characterized by one of a predefined set of grating vectors, wherein each said pixel has one non-diffracting state and at least one diffracting state, wherein each said ESBG pixel when in its diffracting state diffracts light out of said total internal reflection path through one of said substrates into one of a predefined set of output light paths.