Patent ID: 7938568

Claim:
A light emitting diode (LED) backlight device comprising: a light guide plate, a light module composed of a plurality of LEDs, and a haze structure disposed between a light incident surface of the light guide plate and each LED, wherein a haze value of the haze structure is varied with a high value at a position corresponding to an optical axis of each of the LEDs and a low value at a position further away from the optical axis of the nearest LED, and wherein the haze value is a ratio of a flux of scattering light deflecting from an incident direction and a flux of transmitting light in the incident direction, and the haze value at a position in the haze structure is changed according to the following expression: y =sin [π(80−| x |)/180]*100% xε [−74,0]∪[0,74] y=10% xε[−80,−74]∪[74,80] wherein x represents the angle away from the optical axis of the nearest LED at the position, and y represents the haze value.