Patent ID: 7547129
Filing Date: 2009-06-16
Classification: G02B

Abstract:
1. A light source apparatus, comprising: a light guide member having a flat light output surface and a light diffusion surface opposite said light output surface, said light diffusion surface having plural diffusion features arrayed in rows that are parallel to a first side surface of said light guide member, each of said plural diffusion features having a first inclined surface inclined at a first angle relative to said light diffusion surface, a second inclined surface inclined at a second angle relative to said light diffusion surface, said second angle being greater than said first angle, and a flat center portion between said first and second inclined surfaces that is parallel to said light diffusion surface; a first light source on said first side surface of said light guide member and second light source on a second side surface of said light guide member opposite said first side surface, wherein light in said light guide member from said first light source internally reflects off said first inclined surfaces toward said light output surface and wherein light in said light guide member from said second light source internally reflects off said second inclined surfaces toward said light output surface; and an optical member adjacent and parallel to said light output surface, said optical member including a flat plate and an array of reflective surfaces that internally reflect, toward said flat plate, light received from said first inclined surfaces and that refract light received from said second inclined surfaces, wherein said first and second angles and said reflective surfaces are arranged to that said flat plate outputs light originating from said first light source in a first angular range and outputs light originating from said second light source in a second angular range that is wider than said first angular range.