Light guide and liquid crystal display device using it

Abstract

On a light exit surface which is the first principal plane of a light guide, multiple projections are fabricated in specific rows. These projections have light exit surfaces and continuous multiple slopes, and are fabricated from optically identical materials having the same refractive index as the substrate of the light guide. The slope farthest from the light entry edge surface is formed as a light exit surface, i.e., a surface which breaks the conditions for the total reflection of the incident light. On the other hand, the slope nearest the light entry edge surface which is the total reflection surface is formed such that the incident light is totally reflected.