LED backlight device
View Patent ↗There is provided a light emitting diode (LED) backlight device comprising a light guide plate and a light module composed of a plurality of LEDs. A haze structure is disposed between a light incident surface of the light guide plate and each LED. Haze value of the haze structure is varied with a high value at a position closing to an optical axis of the LEDs and a low value at a position further away from the optical axis of the LEDs.
1. 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.
2. The LED backlight device according to claim 1 , wherein the haze structure is disposed on the light incident surface of the light guide plate.
3. The LED backlight device according to claim 1 or 2 , wherein the haze value of the haze structure is in a range of 98%-10%.
4. The LED backlight device according to claim 1 or 2 , wherein the haze value is 98% at a position corresponding to the optical axis of each of the LEDs.
5. The LED backlight device according to claim 1 or 2 , wherein the haze value is 10% at a position furthest away from the optical axis of adjacent LEDs.
6. The LED backlight device according to claim 1 or 2 , wherein the haze structure is formed of a plurality of scattering particles, and each particle has a width in a range of about 40 microns to 80 microns and a height in a range of about 20 microns to 40 microns.
7. 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 on a light incident surface of the light guide plate and between the light incident surface and each LED,
wherein a haze value of the haze structure is varied in a range of 98%-10% 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 each of the LEDs, 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.