Patent ID: 7901125
Filing Date: 2011-03-08
Classification: F21V,G02B,G02F

Abstract:
1. A planar lighting device comprising: a light source; and at least one light guide plate disposed opposite to said light source, wherein said light guide plate has a light entrance plane opposite to said light source and a light exit plane containing one side of said light entrance plane and increases in thickness perpendicular to said light exit plane with an increasing distance from said light entrance plane, wherein said light guide plate contains scattering particles for scattering light entering through said light entrance plane and propagating inside of said light guide plate, wherein said light guide plate is a flexible light guide plate formed of a transparent resin containing at least a plasticizer mixed therein, said plasticizer giving a flexibility to said light guide plate, and wherein at least one of said light exit plane and a plane of said light guide plate in an opposite side of said light exit plane has at least one of an outwardly curved shape and an inwardly curved shape with respect to a direction of optical axis of the light emitted by said light source and incident on said light entrance plane.