| 摘要 |
PROBLEM TO BE SOLVED: To provide a plane light source which can radiate uniform light in a large area by using a LED capable of saving an electric power. SOLUTION: A light diffusion board 1 is provided at one surface of a box body 2. A light emission source 3 is mounted which has a directivity in a substantially parallel direction to one plane of the light diffusion board 1, and also a reflection board 6 is provided under such condition that it has an inclined plane to reflect light from the light emission source 3 to the light diffusion board 1 side. Plural sets of the light emission sources 3 and the reflection boards 6 are provided in the box body 2 so that the light reflected by the reflection board 6 is directed to the light diffusion board 1 side. |
