In the direct-light-type backlight module, besides uniformity, the efficiency of light is also the important property. The common method is using optical ray-tracing of business software to simulate. But using optical software costs a lot of time and they have no optimum function. It can not satisfy speedy simulation of requirement to design and research. We change structure of bottom reflector in the backlight module, to add triangular reflect object between lamps. They can decrease rays' angle with normal, and collimate direction of rays. Then build up program include ray-tracing, distribution of illumination , and optimization to reduce time for simulation. We optimize both uniformity and efficiency of light, and using optical software to test and verify. The result of optimization would reduce the cost of module. To simulate 32″ 16:9 panel, depth is 2.5 cm, number of lamps is 10 with triangular reflect object and to add easy scatter of diffuser on module, the optimal distribution of light for half-intensity angle is 46°, and uniformity is also over 80%.