| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface luminous device used for a liquid crystal back light, a panel meter, indicator lamp and a surface luminous switch, and capable of surface luminescence of high luminance, small color tone difference and small luminance unevenness. SOLUTION: This surface luminous device is provided with a light guide plate containing diffusion material of a different refractive index from that of a light guide body in the translucent light guide body, a light emitting diode optically connected to at least one end face of the light guide plate to emit light from a main plane of the light guide plate, a light diffusion part and a reflection part arranged on a back side of the light guide plate. The diffusion material is benzoguanamine-based resin and/or polyethylene terephthalate translucent particles of average diameter 3-20 μm and is contained in the light guide plate at a ratio of 0.001-0.4 wt.%. |
