Patent ID: 6435687
Filing Date: 2002-08-20
Classification: G02B

Abstract:
A reflection illumination device comprising a light guide placed in front of an object to be illuminated, a light source arranged around said light guide, and a reflecting mirror placed behind the object,wherein one or a plurality of total reflection areas on which adjacent projections or recesses each having a triangular cross-section and serving to totally reflect light emitted from said light source toward the object are formed and are arranged on a surface of said light guide, each of the projections or recesses is constituted by an inclined surface inclined at a predetermined angle smaller than 90Â°âˆ’(&bgr;+&thgr;0) where &bgr; is the irradiation direction of illumination light from the light source and &thgr;0 is a critical angle of a material for said light guide, toward a reference portion positioned at a predetermined position on said light guide, and a vertical surface vertical to said light guide, and said light source and irradiation means surrounding the light source except for the area illuminating the light guide for parallelly irradiating the total reflection area with light from said light source are arranged at an edge of said light guide in correspondence with the total reflection area.