LIGHT GUIDE PLATE AND BACKLIGHT DEVICE

摘要

A light guide plate comprising an entry surface (11) using at least one side surface, a rectangular exit surface (12) orthogonal to the entry surface (11), and a reflection surface (13) inwardly directed to the exit surface (12), wherein the reflection surface (13) has a deflection pattern that receives a ray of light incoming from the entry surface (11) or the exit surface (12) at a certain angle to the normal to the exit surface (12) and outputs the ray of light at a reduced angle to the normal, the deflection pattern has a plurality of arcuate deflection pattern elements formed on a plurality of concentric circles, the exit surface (12) has an anisotropic diffusion pattern that spreads and transmits a ray of light incoming from the deflection pattern at an angle up to a specified angle with respect to the normal to the exit surface (12), the anisotropic diffusion pattern spreads the ray of light incoming from the deflection pattern so that a diffusion width in a direction orthogonal to the radius direction of arcs of the concentric circles is larger than that in the radius direction, and the center of the concentric circles is positioned on any one of the side surfaces of the light guide plate (10) or in the vicinity thereof.