Patent ID: 7342618
Filing Date: 2008-03-11
Classification: G02B,G02F

Abstract:
1. A back light device for use in a liquid crystal display device, comprising: at least one lamp; a light guide plate for guiding light emitting from the lamp; a diffusing sheet for diffusing light emitting from the light guide plate; at least one prism sheet located on the diffusing sheet, concentrating light; a protecting sheet located on the prism sheet; and a reflector located under the light guide plate, reflecting light directing downward the light guide plate, wherein at least one of an entire edge portion of the diffusing sheet adjacent to the lamp, an entire edge portion of the protecting sheet adjacent to the lamp, or an entire edge portion of the reflector includes a printing portion made of colorless ink containing a light scattering agent such that light reflected from a bottom surface of the display device that causes constructive interference with light emitting from the lamp is scattered thereby preventing a bright line on the display device and the printing portion is formed as a single body.