Patent ID: 7637647

Claim:
A back light module, comprising: a back plate; a light source, disposed on the back plate; a lens, disposed on the back plate and covering the light source, wherein the bar lens comprises: a top center transparent surface, disposed above the light source; a right top total internal reflection surface, connected to the top center transparent surface, wherein a first angle is formed between the right top total internal reflection surface and the back plate; a right first emitting surface, connected to the right top total internal reflection surface, wherein a second angle is formed between the right first emitting surface and the back plate; a right second emitting surface, connected to the right first emitting surface, wherein a third angle is formed between the right second emitting surface and the back plate; a right bottom total internal reflection surface, connected to the right second emitting surface, wherein a fourth angle is formed between the right bottom total internal reflection surface and the back plate; a right incident surface, connected to the right bottom total internal reflection surface, wherein a fifth angle is formed between the right incident surface and the back plate; a left top total internal reflection surface, connected to the top center transparent surface, wherein a sixth angle is formed between the left top total internal reflection surface and the back plate; a left first emitting surface, located on the left of the left top total internal reflection surface, and connected to the left top total internal reflection surface, wherein a seventh angle is formed between the left first emitting surface and the back plate; a left second emitting surface, connected to the left first emitting surface, wherein an eighth angle is formed between the left second emitting surface and the back plate; a left bottom total internal reflection surface, connected to the left second emitting surface, wherein a ninth angle is formed between the left bottom total internal reflection surface and the back plate; a left incident surface, connected to the left bottom total internal reflection surface, wherein a tenth angle is formed between the left incident surface and the back plate; and a center bottom transparent surface, connected to the left incident surface and the right incident surface, and located between the top center transparent surface and the light source.