| 摘要 |
<p>In order to provide a light guide plate which has high light utilization efficiency and can emit light having less unevenness of luminance, and in which the a part near the center of a screen has a brighter distribution than that in a peripheral part of the screen, scattering particles are multi-dispersed particles produced by mixing particles having different particle diameters, the light guide plate has at least two layers which are overlied on each other in the direction almost perpendicular to the light output surface and contain the scattering particles at different particle concentrations, the at least two layers comprise a first layer which has a particle concentration of Npo and is arranged on the light output surface side and a second layer which has a particle concentration of Npr and is arranged on the backward side relative to the firs layer, Npo and Npr meet the relationship represented by the formula Npo < Npr, the cross section of the light guide plate on the light output surface side has a concaved shape when the cross section is taken in the direction perpendicular to the light incident surface, and the thicknesses of the first layer and the second layer are changed in the direction almost perpendicular to the light output surface so as to change the concentration of the synthetic particles in a part of the light guide plate which corresponds to the concentration-changed layers.</p> |
