Patent ID: 7991257

Claim:
A method of manufacturing an article comprising: a) providing a first light transmitting material of refractive index n L1x in a first axis x; b) extruding the first light transmitting material into a first film comprising a first surface and a second surface; c) embossing the first surface of the first film to achieve a first plurality of inverted light collimating surface features on the first surface; d) extruding a second light transmitting material of refractive index n H2X in the first axis x onto the first surface of the first film forming a substantially planar third surface; e) extruding a third light transmitting material of refractive index n H3X in the first axis x onto the second surface of the first film; f) embossing the third light transmitting material to achieve a fourth surface comprising a plurality of light collimating surface features.