比较研究了基于Von Karman 折射率谱下大气湍流中单透镜和与单透镜直径相同的透镜阵列的空间光到单模光纤耦合效率，并给出了相应表达式。设计了小口径透镜阵列的空间光-单模光纤耦合结构，证明采用阵列中每个透镜直径是空间相干半径2~3倍的结构具有最好的耦合效果。理论分析和实验结果表明：当通信距离足够远时，透镜阵列的耦合效果优于等口径耦合效果单透镜。

Coupling efficiency expression of single-mode fiber to single lens and lens array with the same single lens diameter is analyzed under Von Karman turbulence. The structure of small caliber lens array is designed. It is proved that an array with each receiving aperture which is 2 to 3 times of the spatial coherent radius is more suitable for a long distant free space optical communicaton system under strong turbulence and long communication distance, because the system has best coupling effect. It is proved theoretically and experimentally that the coupling efficiency of lens array spatial light is better than that of single lens of equal diameter within sufficient distance.