摘    要
 
汽车后视镜反映汽车后方、侧方和下方的情况，使驾驶者可以间接看清楚这些位置的情况，扩大了驾驶者的视野范围。汽车后视镜的控制应简单可靠，并且可以依据驾驶员的要求随时进行调节。
此次设计针对机械触点式电动后视镜开关存在缺点，依据赛马轿车电动后视镜的结构进行必要的技术改进。分析其触点烧蚀的原因，进行电路设计，实现对电动后视镜的控制。结合单片机的发展及其在汽车上的应用，提出利用单片机控制电动后视镜转动的设计方案。取消机械触点，并对控制电路进行优化设计以及部分改装，使控制线路简化，从而在保证实现电动后视镜控制，同时减少了原车电路复杂的控制线束。在不破坏原车结构的同时，便于拆卸与安装，使用控制简单可靠。具有很好的互换性。

关键词：电动后视镜；单片机；控制电路；直流电动机；优化设计

ABSTRACT
 
Motor vehicle rear-view mirror to reflect the rear, side and the bottom of the situation, so that drivers can see clearly the location of the indirect, expanded the scope of the vision of motorist. The rear-view mirror control of the car should be simple and reliable, and the driver can be based on the request at any time to regulate by the driver.
The contact is designed according to the shortcomings of the mechanical-electrical switch mirrors, based on the structure of the the race car’s rear-view mirrors and complete necessary technical improvements. Analysis of the reason for the erosion of their contacts and take the designation of the circuit, so that finish the implementation of the manipulation of electric rearview mirror. Then joined the development of SCM  and consider its application in the automobile, and proclaim the designation by using SCM to control rotating electric mirror. However this design canceled the mechanical contact and optimize the control circuit design and make some new modifications, in order to simplify the control lines. In order to ensure that the realizations of electrical control of the rear-view mirror of the original car at the same time it can reduce the complexity of the control circuit wiring harness. While the car does not destroy the original structure. For demolition and installation, the use of simple and reliable control.And it has a wonderful interchangeability.

Key words： Electric Rear-view Mirrors； Single-Chip Microcomputer；Control Circuits；Delect Current Motor；The Optimization Design