LIGHT GUIDE PLATE, LIGHT SOURCE APPARATUS, AND PLANE EMISSION APPARATUS

PROBLEM TO BE SOLVED: To make effective use of light coming from a semiconductor light emission element into a light guide plate. SOLUTION: A light source device 8 comprises a light source consisting of a light emitting part having concentric inclined face parts on the inner and outer surfaces of its upper portion, with the inclined face part of the inner surface causing total reflection of the light coming from the semiconductor light emission element, and with the inclined face part of the outer surface breaking a critical angle so as to allow the light to exit radially in every direction; a guide collar 9 taking the form of a tube with a horizontally L-shaped cross section and having a flange with an outwardly spreading bottom; and a base 10 on which the light source and the guide collar 9 are provided. The light guide plate 2 has a plurality of incident parts 7 each taking the form of a columnar hole or a recess and arranged in parallel with a side face part 5, on a back face part 4 near at least one side part. The side face part facing each incident part 7 is provided in a position opposite to each incident part 7, while taking the form of an arc with respect to a position to which it is translated from the center position of each incident part 7 in the inward direction of the light guide plate 2. A reflector or a case 11 covers the portions of the light guide plate 2 other than its exit face part and is reflective. COPYRIGHT: (C)2006,JPO&NCIPI