全光纤激光阵列主动相位控制技术研究进展

全光纤激光阵列主动相位控制利用全光纤网络实现阵列激光的活塞相位内部探测与控制,具有结构紧凑、无需外部反馈光学器件和易于扩展等优点,是大阵元规模光纤激光相干合成重要发展方向之一。采用全光纤相位探测结构,介绍了全光纤激光阵列主动相位控制技术的系统原理和利用光纤耦合器实现相位锁定的过程,总结了全光纤激光阵列主动相位控制关键技术,通过优化算法实现全光纤激光阵列主动相位控制验证实验。探讨了在全光纤结构主动相位控制中π相位模糊问题及解决方法,给出了利用双波长探测实现消除π相位模糊问题的仿真结果。最后梳理了全光纤激光阵列主动相位控制研究现状,并从路数扩展、功率提升和应用等方面进行了展望。

Research progress of active phase-locking technique of an all-fiber coherent laser array

The all-fiber laser array with active phase control uses an all-fiber network to realize internal detection and control of piston phases, which is one of the important development directions of large-scale fiber laser coherent beam combining. It has the advantages of compact structure, no external feedback optical elements and easy expansion. The phase detection based on an all-fiber structure is employed in this paper. The principles of the active phase control method of an all-fiber laser array and the phase-locking process by fiber couplers are introduced. Then, the key techniques are summarized, and the proof-of-concept experiments are carried out based on optimum algorithms. The issue of π phase ambiguity is discussed and the numerical simulation result is given by double wavelength detection. At last, the research status is introduced, and the prospects are presented from the perspectives of expansion, power enhancement and applications.