Patent ID: 6461007
Filing Date: 2002-10-08
Classification: G02B,Y10S

Abstract:
A spread illuminating apparatus comprising:a transparent substrate formed of a light-transmissible material; and a light source comprising a bar-like light conductive member and spot-like light sources disposed on both ends of said light conductive member and disposed along and close to an end surface of said transparent substrate; in which an optical path conversion means comprising a plurality of grooves and a plurality of flat portions adjacent to said grooves is formed on a side surface of said light conductive member; in which a depth of said grooves increases in proportion to an increase in distance from each of said spot-like light sources toward a predetermined position where a deepest groove is formed; and in which a light reflection pattern comprising a plurality of grooves and a plurality of flat portions adjacent to said grooves is formed on an upper surface of said transparent substrate with said plurality of grooves oriented to have a predetermined inclination angle with respect to an optical axis of said light source, characterized in that said predetermined position of said deepest groove is shifted from a center of said light conductive member toward either of said spot-like light sources.