LIGHT GUIDING PLATE FORMED OF TRANSPARENT RESIN, PLANAR LIGHT SOURCE, AND LIGHT GUIDING PLATE MANUFACTURING METHOD

摘要

A light guiding plate is formed by transparent thermoplastic resin and has a first surface, a second surface opposing to the first surface, a first side surface, a second side surface, a third side surface opposing to the first side surface, and a fourth side surface opposing to the second side surface. The first surface has a convex portion and/or a concave portion. The length of the light guiding plate in the longitudinal direction which is the distance between the first side surface and the third side surface is not smaller than 40 mm and not greater than 70 mm. The thickness of at least 80% of the light guiding plate is not smaller than 0.1 mm and not greater than 0.55 mm.