| 摘要 |
PROBLEM TO BE SOLVED: To obtain a surface light source of an edge light system which is uniform in luminance. SOLUTION: A light guide plate 11, which is a planar member made of a translucent member and forms irregular reflection parts 15 constituted of a plurality of semispherical recesses on a lower surface is constituted of a light emitting part 12 in which an upper surface 12a, is provided as a light emitting surface and a planar shape is a substantially right-angle quadrilateral and a plurality of light source parts 13 extending a virtual side surface (m) on an LED 20 side of the light emitting part 12 to the LED 20 side. The LED 20 is disposed corresponding to each light source part 13. Within the light source part 13, a reflection and refraction part 16 constituted of a through-hole or a non-through-hole is provided so as to be opposed to the LED 20. An LED 20 side boundary surface 16b of the reflection refraction part 16 is a reflection refraction surface, in which the thickness direction cross section of the light guide plate 11 is vertical and plane direction cross section is inclined to the LED 20. On both side surfaces 13d on the LED 20 side of the light source part 13, the irregular reflection parts 15 constituted of a plurality of grooves having substantially circular arc shapes in cross section substantially parallel to the thickness direction of the light guide plate 11 are provided. |
