Patent ID: 6533428
Filing Date: 2003-03-18
Classification: G02F

Abstract:
A flat-surface type display device, comprising:a display panel of a light transmissive type; a surface light source device of an edge light system for emitting light to said display panel from behind; a circuit board, connected to said display panel through a wiring board, for supplying said display panel with a signal necessary to drive said display panel; and a mechanical portion for housing and retaining said display panel, said surface light source device, and said circuit board, wherein said surface light source device includes a light guide plate having a flat light emitting surface, and a back surface opposing to said light emitting surface, and said light guide plate has a light-incident end on which light emitted from a light source and a light-anti-incident end remote from said light-incident end, said back surface includes (1) an inclined flat surface portion disposed in an area near said light-incident end, where the thickness of said light guide plate under said inclined flat surface portion decreases linearly from the end near to said light-incident end toward the end remote from said light-incident end and (2) a parallel flat surface portion, following said inclined flat surface portion, disposed in an area near said light-anti-incident end, which is substantially parallel with said flat light emitting surface where the thickness of said light guide plate under said parallel flat surface portion is reduced from said light-incident end, and said circuit board is disposed in a position opposing to said parallel flat surface portion.