Patent ID: 9329328
Filing Date: 2016-05-03
CPC Classification: G02B

Claim Text:
1. A backlight module, comprising: a light guide plate, having a light emitting surface, a bottom surface opposite to the light emitting surface, a light incident surface connecting with the light emitting surface and the bottom surface, a plurality of first microstructures on the bottom surface, and a plurality of fourth microstructures on the bottom surface, wherein each of the first microstructures is a recessed structure and comprises a first surface and a second surface, the first surface faces to the light incident surface, and an included angle between the first surface and the bottom surface ranges from 15 degrees to 27 degrees, the first surface of each of the first microstructures is located between the second surface and the light incident surface, and an included angle between the second surface and the bottom surface ranges from 50 degrees to 90 degrees, and wherein each of the fourth microstructures is a protruding structure attached to the bottom surface, a distribution density of the fourth microstructures away from the light incident surface is higher than a distribution density of the fourth microstructures close to the light incident surface, and a distance between the adjacent fourth microstructures ranges from 30 μm to 500 μm, wherein the fourth microstructures are disposed between adjacent first microstructures, and a gap is between each of the fourth microstructures and the first microstructures; a light source, providing a light beam, and the light beam entering the light guide plate via the light incident surface, wherein an included angle between a light emitting direction of the light beam emitted from the light emitting surface of the light guide plate and a normal direction of the light emitting surface is greater than 30 degrees; and at least one prism sheet, disposed above the light emitting surface.