Patent ID: 9097826
Filing Date: 2015-08-04
Classification: G02B

Abstract:
1. A collimating illumination system, comprising: a planar optical waveguide defined by a first major surface and an opposing second major surface extending parallel to said first major surface, said waveguide is configured for guiding light along a general propagation direction in response to optical transmission and a total internal reflection from at least one of said first and second major surfaces; a plurality of linear collimating elements formed in said first major surface and aligned parallel to said general propagation direction; and a plurality of light extraction elements arranged into a parallel array of linear strips, each of said strips extending parallel to said linear collimating elements and disposed near or at a focal area of at least one of said linear collimating elements; wherein each of said strips of said light extraction elements is configured to receive light propagating within said planar optical waveguide along said general propagation direction and redirect at least a substantial portion of the received light toward said linear collimating elements and out of said waveguide; wherein said waveguide is a lens array having a thickness T defined from the following expression: where R is a radius of curvature of lenses forming said lens array and n is the index of refraction of a material of said lens array.