Currently, the mainstream autostereoscopic displays have a shortcoming: the insufficient brightness. It causes bad influence on the using of autostereoscopic displays. To improve the brightness, a new design method of the backlight module is needed. In this article, one high-brightness light emitting diode (LED) is used, and the light is concentrated to the eyes of observer by using a Fresnel lens and many cylindrical lenses. The brightness is improved significantly. When the user position changes greatly, another LED is lighted up to replace the former. Imitation and experimental results indicate that this method is feasible. Compare with previous backlight modules, this backlight module is brighter and need less electrical energy, and is more suitable for cockpits.