Patent ID: 8201984

Claim:
A backlight module, comprising: a light guide plate, having a first surface, a second surface opposite to the first surface, and a light incident surface connecting the first surface and the second surface; a plurality of micro-structures, disposed on at least one of the first surface and the second surface, wherein a size of each of the micro-structures is smaller than or equal to 150 micrometers; at least one light source, disposed beside the light incident surface, wherein the light source is capable of emitting a light beam, the light incident surface is capable of guiding the light beam into the light guide plate, and the first surface is capable of guiding the light beam away from the light guide plate; and a first prism sheet, comprising: a first transparent substrate, wherein the first surface is located between the second surface and the first transparent substrate; and a plurality of first prism structures, wherein the first transparent substrate is disposed between the first surface and the first prism structures, and each of the first prism structures has a first vertex angle protruding away from the first transparent substrate and ranging within a range of 67 degrees to 83 degrees.