光电耦合器是近几年来发展较快的一种半导体光电器件，其输入与输出在电气性能上是完全隔离的，因而在各种电子设备上得到广泛的应用。众所周知，光电耦合器是由发光源和受光器两部分组成。用作光电耦合器中的发光源常见的是砷化镓发光二极管；受光器普遍采用硅光敏器件、光敏 Optocoupler is a semiconductor optoelectronic device developed rapidly in recent years. The input and output of the optoelectronic coupler are completely isolated in electrical performance, and are widely used in various electronic devices. As we all know, optocouplers by the light source and receiver two parts. Commonly used as a light-emitting source in a photocoupler is a gallium arsenide light-emitting diode; a light-receiving device generally uses a silicon photosensor, a photosensitive