中文摘要：

有效将激光耦合进单模光纤是自由空间光通信的关键技术。为了改善聚焦光束质量和降低耦合损耗，首先设计了消球差非球面透镜，并采用精密光纤支架对耦合光纤进行准确定位使耦合光聚焦在光纤端面上。实验表明，该耦合系统的耦合效率达到60％以上。

英文摘要：

Effectively coupling the coherent laser into singlemode fiber is a key technology for freespace optical communication. In this paper, we analyze how to mitigate the efficiency degradation due to lens spherical aberration and fi ber position deviation. Firstly, an aspherical lens was designed to improve the focused spot quality and thereby de crease the coupling loss. Then, a precision fiber holder was adopted to precisely fix the fiber position and make the fo cal plane of the light coincided with the endface of the fiber. The measured coupling efficiency of 60% is achieved in the experiment.