A brand new design concept is proposed in this paper. In order to increase the efficiency of light emission, a series of diffusion plates with different hollowed triangular prism structure is designed to guide the light toward to dark region. Tracepro software is used and the results of simulation show that the uniformity of such diffusion plate can be improved as high as 91%. Moreover, the efficiency and the brightness of the backlight module could also be obtained to be about 80% and 255 nits, respectively.