LIGHT GUIDE PLATE, ILLUMINATING DEVICE USING SAME, AREA LIGHT SOURCE AND DISPLAY

摘要

A light guide plate comprises a first light guide layer composed of a material having a refractive index n1, a diffusing light guide layer having a function to diffuse a light, and a reflective means for directing a light propagating in the first light guide layer to the diffusing light guide layer. The reflective means is formed on a surface of the first light guide layer that is opposite to a light guide surface on which a light is incident. The diffusing light guide layer comprises at least a second light guide layer composed of a material having a refractive index n2 (n2 <n1) and a diffusing layer for diffusing a light propagating in the second light guide layer.