Patent ID: 8804072

Claim:
A backlight module, which comprises a light guide plate and a light source, the light guide plate comprises a reflection surface and a light emitting surface, in which the reflection surface and the light emitting surface have two bottom surfaces and two lateral surfaces located therebetween, the two bottom surface comprises a supporting surface, the light source has an elongated shape and is disposed corresponding to one of the lateral surfaces of the light guide plate, the light source and the light guide plate have a positioning post disposed therebetween, wherein: the backlight module further comprises a support post, the supporting surface has an inclined contact surface disposed thereon, the inclined contact surface is formed by sinking a portion of the supporting surface, the inclined contact surface has a specific slope, and the support post is attached to the inclined contact surface; wherein a gravitational force is in a direction parallel to a length of the light source, a force acting between the light guide plate and the support post is formed when a change of the light guide plate occurs along the gravitational force, the support post pushes the light guide plate toward the light source under the acting force, the support post also supports the light guide plate along a direction opposite to the gravitational force.