多抖动法主振荡功率放大器相干合成技术

 采用多抖动相位控制方法实现了两路和三路1 Ｗ量级光纤放大器的相干合成，对实验结果进行了详细分析。实验中，将种子光源输出激光分为两路（或三路），分别通过光纤放大器进行功率放大，并采用多抖动法实现相干合成。控制系统开环时，远场光斑条纹模糊不清，两路和三路合成时条纹对比度分别为0.19和0.12；系统闭环时，远场光斑条纹清晰可见，对比度提高到0.93和0.81，合成效率分别为80%和77%。此外，对两路和三路的合成效果进行了比较,指出了各路的控制资源对合成效果的影响。

Coherent beam combining of MOPA with multi-dithering technique

Coherent beam combining of two and three watt-level fiber amplifiers is demonstrated with multi-dithering technique used for phase control. In the experiment, the master laser is split into two or three channels and the power of each channel is amplified by a fiber amplifier. When the control loop is open, the far-field pattern is dynamic and blurred, and the fringe contrasts for combining are 0.19 for two beams and 0.12 for three beams. When the control loop is closed, the far-field pattern is stable and clear, the fringe contrasts for two- and three-beam combinings are improved to 0.93 and 0.81 respectively and the corresponding coherent combining efficiencies are 80% and 77%. In addition, the experimental results of two- and three-beam combinings are compared and the effect of each control on coherent beam combining is given.