As is known to all, rearview mirrors are very important for driving safety. However, traditional rearview mirrors have some drawbacks. For example, environment may have a huge influence on them: when the light is dim, the mirror is covered with mist, or the brights from the cars behind are too strong, drivers will find it difficult to see what is happening behind the vehicle, which increases the risk of driving. In addition, the traditional rearview mirror has an inevitable effect on the air resistance of the vehicle, and on the field of view on the side of the vehicle.