Patent ID: 8419265

Claim:
A backlight module, comprising: a front frame; a backboard, wherein the front frame and the backboard define opposite outermost surfaces of the backlight module, the backboard comprising: a frame coupled with the front frame, the frame having a plurality of plates surroundingly defining an empty part and at least one side wall extending from one of the plates to be coupled with the front frame, wherein each one of the plates has a first surface, a second surface opposite to the first surface, at least one rib, and at least one trough, the rib is disposed on the first surface, the rib protrudes from the first surface, the rib is spaced apart from the side wall, the trough is disposed in a portion of the second surface which is opposite to a portion of the first surface where the rib is disposed, and a bottom of the trough is located at a different level from the level of the other portions of the second surface other than the portion of the second surface where the trough is disposed; and a light-shield plate covering the empty part; and a light source disposed between the front frame and the backboard.