LIGHT GUIDING PLATE FOR SURFACE LIGHT SOURCE DEVICE AND BACK LIGHT UNIT WITH CONTROLLABLE VIEWING ANGLE COMPRISING THE SAME

摘要

The present invention relates to a light guide plate for a surface light source device and a back light unit including the same and, more specifically, to a light guide plate for a surface light source device and a back light unit which have high front brightness and excellent uniformity in brightness without having a moire phenomenon, reduce use of optical sheets stacked on the light guide plate, make a liquid crystal display module slim, simplify a manufacturing process, reduce manufacturing costs, and freely control a viewing angle to have excellent visibility in various angles. For this, the light guide plate for a surface light source device according to the present invention comprises an incident surface having incident light thereon from lamps disposed along a predetermined axis, an emitting surface emitting the incident light therefrom, and a back surface facing the emitting surface; wherein an engraved lenticular pattern is formed on the emitting surface, multiple unit cells having microprism patterns engraved thereon are distributed and arranged on the back surface, and a crossing angle of a microprism arrangement axis, formed by a ridge direction of the microprism patterns, and of an arrangement axis of the lamps is disposed in an alternate angle. [Reference numerals] (AA) Enlarging