相干光通信技术是提高接收机灵敏度,发展大容量高码率激光通信系统的重要技术手段,光学桥接器将信号激光和本振激光链接到光电探测器进行相干探测处理,是相干光通信系统的关键器件之一。对近20多年来发展的光学桥接器进行了总结和分类,介绍了不同光学桥接器的原理、构造和性能,分析了光学桥接器的关键技术。 Coherent optical communication technology is an important technical means to improve receiver sensitivity and develop high-capacity high-rate laser communication system. The optical bridge links the signal laser and the local laser to the photodetector for coherent detection processing. One of the key devices. The development, classification and classification of optical bridges in recent 20 years are introduced. The principle, structure and performance of different optical bridges are introduced. The key technologies of optical bridges are analyzed.