US 10,890,710 B2
Display device and backlight module thereof
Shih-Fu Tseng, Hsin-Chu (TW); Chia-Hung Chen, Hsin-Chu (TW); and Kai-Teng Shih, Hsin-Chu (TW)
Assigned to AU OPTRONICS CORPORATION, Hsin-Chu (TW)
Filed by AU OPTRONICS CORPORATION, Hsin-Chu (TW)
Filed on Feb. 10, 2020, as Appl. No. 16/785,702.
Claims priority of application No. 108104489 A (TW), filed on Feb. 11, 2019.
Prior Publication US 2020/0257036 A1, Aug. 13, 2020
Int. Cl. F21V 8/00 (2006.01)
CPC G02B 6/0061 (2013.01) [G02B 6/003 (2013.01); G02B 6/0036 (2013.01); G02B 6/0068 (2013.01); G02B 6/0088 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A backlight module, comprising:
a collimated light source configured to generate a collimated light; and
a light guide plate having a bottom surface and a top surface opposite to each other and a light entrance surface connected to an end of the bottom surface and an end of the top surface respectively, the light entrance surface being disposed toward the collimated light source for receiving the collimated light,
wherein, the bottom surface inclines toward the top surface from the end of the bottom surface connected to the light entrance surface, and a first angle exists between an extending direction of the bottom surface and an extending direction of the top surface, a plurality of first grooves are disposed side by side on the bottom surface and respectively extend along a length direction of the light entrance surface, each of the first grooves has a first light receiving surface closer to the light entrance surface, and each of the first light receiving surfaces extends toward the top surface and inclines away from the light entrance surface, and each of the first light receiving surfaces has a first end facing the top surface, wherein compared to a vertical projection of the first end of the first light receiving surface closer to the light entrance surface on the light entrance surface, a vertical projection of the first end of the first light receiving surface farther from the light entrance surface has a vertical projection on the light entrance surface is closer to the top surface, wherein a first acute angle exists between an extending direction of the first light receiving surface of each of the first grooves and an extending direction of the light entrance surface, the first acute angle is equal or larger than 45 degrees, a plurality of second grooves are disposed side by side on the top surface and respectively extend along the length direction of the light entrance surface, each of the second grooves has a second light receiving surface closer to the light entrance surface, and each of the second light receiving surfaces extends toward the bottom surface and inclines away from the light entrance surface, wherein each of the second grooves has a second wall surface farther from the light entrance surface and connected to the second light receiving surface, an angle between the second wall surface and the second light receiving surface is 90 degrees−abs(atan(n*sin(θ)/(1−n*cos(θ)))) (n: a refractive index of the light guide plate,θ=abs((the first acute angle)*2-90 degrees)).