| 摘要 |
PURPOSE:To eliminate the unbalance (irregularity) of brightness and to efficiently utilize light emitting from a light source by making peak and trough parts of a saw tooth shape below a light source different in reflection factor. CONSTITUTION:A saw-tooth undulating reflecting plate 5 is interposed between the light source 2 and a lamp house 1. Namely, a light diffusion plate is incorporated in a saw-tooth shape between a cylindrical light source 2 and the lamp house 1 and a surface display panel 3 is irradiated with the light from the cylindrical light source 2. Further, when this backlighting device is made thin, the light from the cylindrical light source 2 appears intensely on the surface display panel 3 to generate an irregularity in brightness, so the reflection factor of the trough parts of the saw tooth shape below the light source is decreased. Consequently, the loss of the light reaching the surface display panel 3 is reduced, efficient utilization is available and thin size and a uniform brightness distribution are realized. |
