| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a light diffusion plate in which the adjustment of a light source position is not necessary, a lamp image is eliminated, and the luminance in the emission surface is excellently uniformalized. <P>SOLUTION: One of the main surfaces is an incident surface for mainly receiving light, another one is an emission surface mainly emits light, and a plurality of convex parts is periodically formed at least on one of the main surfaces. The total light transmission rate when the light enters at a prescribed angle α against the normal line direction of the incident surface is fifty percent or larger, and it is 1.05 times to 5 times of the rate when light enters vertically. Ten to fifty percent of the light entered at the angle α against the normal line direction of the incident surface of the light diffusion plate emits at an angle θ2' in the range of (-π/12) to (π/12) against the normal line direction of the emission surface. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
