Backlight module and light guide plate thereof

A backlight module, comprising:

• at least one light source;
• and
• a light guide plate comprising at least one incident surface for receiving light beams from a corresponding light source, an emitting surface, and a bottom surface opposite to the emitting surface for scattering and reflecting the light beams in the light guide plate, and directing the light beams to the emitting surface, a plurality of stairway-shaped protrusions being disposed on the emitting surface;
• wherein the at least one light source is provided adjacent to the at least one incident surface, respectively, and each of the stairway-shaped protrusions bas a plurality of rectangular steps.

A light guide plate used with at least one light source, comprising:

• at least one incident surface for receiving incident light beams from a corresponding light source;
• an emitting surface;
• and
• a bottom surface opposite to the emitting surface for scattering and reflecting the light beams in the light guide plate, and directing the light beams to the emitting surface;
• wherein
• a plurality of protrusions are side by side disposed on the emitting surface in a lateral direction, and each of said protrusions extends in a longitudinal direction perpendicular to said lateral direction and defines a plurality of tiny projections side by side arranged in said lateral direction on an exterior thereof;
• wherein
• each of said tiny projections extends along said longitudinal direction, and for each of said protrusions which has two oblique sides thereof, there are two sets of tiny projections located on said two oblique sides, respectively.