Patent ID: 8147111

Claim:
A light guide plate, comprising: a body having a bottom surface, a light emitting surface opposite to the bottom surface, and a plurality of side surfaces connected between the bottom surface and the light emitting surface, wherein the light emitting surface has a central area and at least one peripheral area disposed thereon, and the peripheral area is located outside the central area; and a plurality of prism microstructures disposed on the light emitting surface and the bottom surface, wherein the prism microstructures on the light emitting surface comprise a plurality of first prism microstructures located in the central area and a plurality of second prism microstructures located in the peripheral area, and a top angle θ 2 of each of the second prism microstructures is greater than a top angle θ 1 of each of the first prism microstructures, wherein the prism microstructures on the light emitting surface comprise a plurality of triangular prisms arranged in parallel to each other, and the prism microstructures on the bottom surface comprise a plurality of triangular prisms arranged in parallel to each other, and relative to the bottom surface, each of the triangular prisms on the bottom surface has a first height corresponding to the central area and a second height corresponding to the peripheral area, and the second height is greater than the first height.