Patent ID: 9470838
Filing Date: 2016-10-18
CPC Classification: G02B

Claim Text:
1. A lighting device, comprising: a light guide having a first major surface, the first major surface having first and second diffractive surface features formed in first and second portions thereof respectively, at least one of the first and second diffractive surface features adapted to couple guided-mode light out of the light guide; and a patterned light transmissive layer in optical contact with the second diffractive surface features but not the first diffractive surface features, the patterned layer comprising a second light transmissive medium; a first light transmissive medium in optical contact with the first diffractive surface features but not the second diffractive surface features; wherein the first and second light transmissive media have different first and second refractive indices respectively at a visible wavelength; and wherein the light guide is non-flat.