BACK LIGHT UNIT AND LIQUID CRYSTAL DISPLAY DEVICE USING THE SAME

摘要

Provided are a back light unit and a liquid crystal display device using the same. The present invention includes a light source; a light guide plate facing the light source; an optical sheet formed on the light guide plate; and a refection plate formed under the light guide plate. The light guide plate includes a first side which faces the light source and functions as a light entering surface, a second side facing the first side, a lower surface facing the reflection plate, and an upper surface which faces the lower surface and functions as a light emitting surface. Protrusion patterns are formed on the lower surface of the light guide plate. Each of the protrusion patterns has a cross-section structure which includes a first side composed of a part of the lower side, a second side extended to one end of the first side, and a third side extended from the other end of the first side. The second side is the nearest side to the light source. The third side is the farthest side to the light source. A second angle between the first side and the third side is smaller than a first angle between the first side and the second side.