Patent ID: 7334934

Claim:
A light guide device, comprising: a main body including: an incident surface; an emitting surface adjoining the incident surface; a reflecting surface opposite to the emitting surface; a plurality of parallel elongate first V-shaped microstructures provided on the reflecting surface; and each first V-shaped microstructures having a triangular cross-section, the triangular cross-section having a first base angle nearest the incident surface, a second base angle furthest from the incident surface and a vertex angle, a distance between adjacent first V-shaped microstructures defining a first pitch, the first pitch being configured to be substantially constant between each particular pair of adjacent first V-shaped microstructures, a base width of the first V-shaped microstructures being defined by the equation y=9.2637×10 −6 x 2 −0.0003x+0.0232, wherein x is the distance between a given first V-shaped microstructure and the incident surface, in units of micrometers, and wherein y is the base width of the given first V-shaped microstructure, in units of micrometers.