Patent ID: 8514349

Claim:
A backlight apparatus comprising a plurality of backlight blocks which are aligned, each block having light sources and a unit light guide plate for guiding light from the light sources to the side of a liquid crystal panel, further comprising: unit diffusion patterns formed on a light exit surface of the unit light guide plate of the backlight block in a staggered alignment; and another diffusion pattern formed on the back of the unit light guide plate, wherein the unit diffusion pattern is of a circle, an ellipse, a rectangle, or a rectangular shape having rounded or beveled corners, wherein the light sources are LEDs, and wherein one side of the unit light guide plate is defined as a light entrance surface, the LEDs are aligned along the light entrance surface, and p≧a≧c is satisfied, where a indicates the size of the unit diffusion pattern in a direction orthogonal to an exit optical axis of an LED on a light exit surface of the unit light guide plate, c indicates the size of an LED emission surface in the direction of alignment of the LEDs, and p indicates the pitch of alignment of the LEDs.