Head Up Display is designed for preventing accident, which can project important information ( e.g. vehicle speed ) onto the front windshield at the eye level of the driver. Besides, the display location and brightness can be adjusted through automatic induction, which can prevent the driver from looking down at the instrument panel and shorten the time of eyes for the blind spot in front. This can avoid breaking rules and regulations due to speeding in many speed-limited sections. What’s more important, it can enable the driver to read the number instantly without shifting horizon, which is of vital value in reducing traffic accidents caused by absent-mind due to looking down.