Patent ID: 8313226

Claim:
A display element for modulating light comprising: (a) an optical waveguide having a refractive index n 1 , an upper surface and a spaced-apart lower surface converging with said upper surface; (b) a micro-prism comprising: a refractive index n 2 , a light input facet optically coupled to said upper surface of said optical waveguide via an optical layer having a refractive index n 3 which is less than said refractive index n 2 and said refractive index n 1 and greater than 1, a light exit facet located above said upper surface of said optical waveguide and inclined opposite to said lower surface of said optical waveguide; and (c) a tilting micro-shutter disposed proximate said upper surface of said optical waveguide; wherein most light rays exiting from said light exit facet of said micro-prism are directed to the viewer when said tilting micro-shutter is at a first position or absorbed in a light absorber when said tilting micro-shutter is at a second position.