LIGHTING DEVICE AND DOCUMENT READER USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a lighting device having high efficiency by reducing loss of a light quantity, providing uniform and stable light irradiation and having a deep light quantity depth. SOLUTION: The lighting device is equipped with a light guide body 1 made of a transparent material and light sources provided at both ends of the light guide body, and the light guide body has an optical area provided on a surface in a length direction; a light exit portion R3 configured such that light emitted from a light source is made incident into the light guide body and light having passed through the optical area is emitted from a surface on one side in the length direction facing the optical area of the light guide; and a tapered portion R2 which is connected to the light exit portion and light sources and forms a tapered surface such that an external surface gradually expands from the light source to the light exit portion. COPYRIGHT: (C)2009,JPO&INPIT