| 摘要 |
PROBLEM TO BE SOLVED: To enhance lighting efficiency of a structure for lighting a transparent substrate provided on a liquid crystal panel by a light source via a light guide body. SOLUTION: In this surface lighting system, a bar-like light guide body 2 is disposed near the side face of a transparent substrate 1 made of a light- transmitting material and the light guide body 2 is brightened by a light emitting diode 3 disposed on an end part thereof. The light guide body 2 is provided with prismatic grooves 2c as optical-path changing means while an optical-path changing plate 7 is disposed between the light guide body 2 and the transparent substrate 1. Rays of light from the light emitting diode 3 enter the light guide body 2 are directed obliquely by the prismatic grooves 2c and enter the optical- path changing plate 7. The rays are refracted by the optical-path changing plate 7 and go vertically into the transparent substrate 1, thus lighting the transparent substrate 1 with high efficiency. |
