Patent ID: 6611303
Filing Date: 2003-08-26
Classification: G02B

Abstract:
A backlight device for a liquid crystal display device, comprising:a light source; a light waveguide plate having an end portion and a front portion; a lamp holder having a lamp reflector, the lamp holder surrounding most of the light source, the lamp reflector reflecting a light to the end portion of the light waveguide plate; and a first prism sheet located on the front portion of the waveguide plate wherein a diffusion sheet is interposed between said first prism sheet and said waveguide plate, the prism sheet having a plurality of convex portions, the convex portions having an inclined line portion with respect to a direction vertical to the front portion of the light waveguide plate, and a curved line portion, the inclined line portion having a predetermined angle with respect to a direction vertical to the front portion of the light waveguide plate, wherein said angle is less than 20Â° and greater than 0Â°.