摘要 |
A light guide includes: a first major surface; a second major surface opposite the first major surface; an array of extraction elements, each element disposed between an upper and lower edge of the first major surface, each upper and lower edge defining a plane therebetween, each element including: a first face adjoining the upper edge, the first face projecting inwardly relative to the plane at a first angle; a second face adjoining the first face, the second face projecting inwardly at a second angle relative to the plane, the second angle greater than the first angle; a third face adjoining the lower edge and the second face, the third face projecting inwardly relative to the plane at a third angle, the third angle greater than the first angle; wherein the first face, second face and third face define an indentation projecting inwardly from the plane defined by the first major surface. |