| 摘要 |
PROBLEM TO BE SOLVED: To reduce light loss in a boundary part when light conductive plates divided into a plural parts are combined, obtain a large light conductive plate, and apply to an LED(light emitting diode) room lighting system in a surface light source device. SOLUTION: Edge surfaces of a plurality of light conductive plates 21, 22 are combined so that light incident to one light conductive plate 21 from a light source 3 is propagated to the other light conductive plate 22 without practically generating total reflection on the boundary edge surface. Light loss on the boundary surface is reduced as much as possible, a large light conductive plate can be obtained by combining a plurality of light conductive plates, and the light conductive plate obtained is suitable for a lighting system, and it is easy to handle for transportation and setting. |
