Patent ID: 6415531
Filing Date: 2002-07-09
Classification: G02B,G09F,H01L,Y10S

Abstract:
A plane-shaped lighting device comprising:a light-directing plate made of a plate-shaped light-transmitting member; and a light source that is placed close to or in contact with one side face of the light-directing plate, wherein: light, which has been emitted from the light source and made to be incident on a light-incident surface on the one side face of the light-directing plate, is taken out from a plane section of the light-directing plate; and a plurality of light-takeoff bodies, each having a recessed shape or a protruding shape, are provided on the plane section of the light-directing plate in a direction parallel to the one side face and in at least two directions that intersect said direction, the light-takeoff bodies being arranged so that the density thereof increases as the distance from the light source increases, and so that each light-takeoff body has a smooth surface.