Patent ID: 7614757
Filing Date: 2009-11-10
Classification: G02B,G02F

Abstract:
1. A backlight unit comprising: a light source which radiates light; a light guide plate, disposed with the light source positioned at a lateral side of the light guide plate, which guides the light incident on the lateral side into the light guide plate; a wire-grid polarizer, comprising a plurality of parallel metal wires formed on one of a top surface and a bottom surface of the light guide plate, which transmits a first polarized component of the light in a substantially perpendicular direction to the metal wires through the one of the top surface and the bottom surface of the light guide plate and reflects a second polarized component of the light in a substantially parallel direction to the metal wires; a reflector which is disposed below the light guide plate and reflects the light emitted out from the light guide plate to an inside of the light guide plate; a polarization converter which changes a polarization of the light not emitted through the top surface of the light guide plate into an opposite polarization; and a micro-structured pattern, formed on a surface of a given layer in the light guide plate, which changes a proceeding direction of the light incident on the micro-structured pattern to be substantially vertical to the top surface of the light guide plate, wherein the surface of the given layer, substantially parallel to the top surface of the light guide plate, is disposed apart from the top surface of the light guide plate, and wherein the given layer on which the micro-structured pattern is formed is the bottom layer of the light guide plate, and the wire-grid polarizer is formed on the top surface of the light guide plate.