Patent ID: 8692464

Claim:
A light guiding plate, comprising: a light transmissive substrate, comprising a first surface and a second surface opposite to the first surface; a plurality of optical structures, configured on the first surface; a plurality of first prisms, configured on the second surface, wherein the first prisms are substantially parallel, and each first prism comprises a first top portion and two first inclined surfaces respectively connected to two sides of the first top portion, the first top portion comprises a first vertex, an included angle of the two first inclined surfaces is θ 1 , a first intersected point formed by extending the two first inclined surfaces has a height H 1 relative to the second surface, a height of the first vertex relative to the second surface is h 1 , and each first prism comprises a first reprint ratio R 1 , R 1 =h 1 /H 1 , wherein each first prism satisfies following conditions: when θ 1 ≦95°, R 1 ≦0.7; when 95°<θ 1 ≦105°, R 1 ≦0.8; when 105°<θ 1 ≦115°, R 1 ≦0.9; and when 115°≦θ 1 , R 1 ≦1; and a plurality of second prisms, configured on the second surface, wherein the first prisms and the second prisms are substantially parallel, and the first prisms and the second prisms are alternately arranged.