Directional backlighting system using a light guide with paired microstructures.

In a conventional edge-lit backlighting system, a light guide with diffusing dots, prism films and diffusers are used to produce desired light distribution. In such a system, the use of prism films helps to collimate the light, but it also increases the cost and reduces the overall optical efficiency. This paper proposes a novel light guide with paired microstructures to produce highly collimated light distribution without using prism films. Each paired microstructure is composed of two different micro-geometries that are placed next to each other. By optimizing the surface angles of a paired microstructure in the light guide, a highly collimated light distribution can be generated without using prism films.