对基于环形腔光反馈的光纤激光被动锁相技术进行了理论和实验研究。建立了一维三路光纤激光阵列的相干组束实验装置, 实现了三束光纤激光的相位锁定, 观测到稳定的干涉图样。研究了光束占空比对远场光斑的影响, 分析了影响腔内损耗的主要因素。观测到相干耦合输出光谱中所存在的多波长峰值随机出现的现象, 通过采用窄带宽滤光片, 可以限制相干耦合输出的光谱范围, 但上述现象仍然存在。从理论上对被动锁相技术中所存在的这种波长随机现象进行了分析和解释。

Technique for passive phase locking of fiber lasers by an all-optical feedback loop is studied theoretically and experimentally. The experimental setup of coherent beam combination of three fiber lasers in one dimension is built, and phase-locking of three fiber lasers is achieved and stable interference patterns are observed. The influence of duty ratios on the interference patterns in the far field is studied. Main factors that affect the cavity loss are analyzed. Random peaks corresponding to different wavelengths are found in the spectrum of coherent output laser. By using a narrow bandwidth filter, the spectral range of coherent output laser can be restricted. However, the phenomenon mentioned above still exists. And theoretical analysis is given to explain these random wavelengths existing in this kind of technique for passive phase-locking.