Optical design of adaptive front lighting system based on digital micro mirror device

The road safety of vehicles in night depends on the street illumination directly. Adaptive Front lighting System(AFS) can automatically provide different illumination modes by adjusting the shape, distance and light distribution of illumination according to the surrounding environment to improve the driving security. Considering the problems that less light efficiency of present AFS, one solution of AFS using Digital Micro mirror Device(DMD) was presented. It consists of lamp, reflector, light pipe, DMD and lens. DMD is the core of this system. And the second light pipe was used to collect the unused light energy. The experimental results show that the light efficiency is improved largely by the using of the second light pipe. And it can achieve different beams easily by accuracy controlling the luminance of every pixel on the screen. Because of its flexibility and higher light efficiency, this scheme is expected to show on market.