基于能动分块反射镜的两路光纤放大器相位探测及其相干合成实验研究

在光纤激光相干合成中，需要探测各路光束之间的平移误差.提出了一种条纹提取算法，利用此算法能得到准确的相位平移扰动.基于此算法，针对两路光纤放大器测量了毫瓦量级的光纤放大器的相位噪声特性，然后采用高速数字处理电路以及能动分块反射镜完成了平移相位扰动的实时校正.实验结果表明，闭环前后条纹对比度从0.09提高到0.25，平移误相位噪声强度的幅值从1053.4 nm降低到116.7 nm，系统校正精度达到1/10λ,控制带宽约为50Hz. 关键词： 能动分块反射镜 条纹提取算法 相位扰动 光纤放大器

Experimental research on phase detection and correction of two fiber amplifier based on active segmented mirrors

The measurement of piston noise is a critical issue in coherent combining of fiber lasers. This paper presents a strip extracting algorithm, which get the amplitude of phase noise in fiber amplifier. By this algorithm, phase noise of fiber amplifier working in 10~(-3)W level is measured and real-time controlled by high-speed digital processing circuit and active segment mirrors. Experimental results indicate, that after closing the loop, fringe contrast improves from 0.09 to 0.25, intensity value of piston noise decreases from 1053.4 nm down to 116.7 nm; the calibration precision and bandwidth of the system achieve 1/10λ and 50 Hz, respectively.