线阵光纤激光相干合成角度扫描控制方法研究

Control method of coherent beam combining angle scanning based on linear fiber array

基于光的干涉理论,对多芯线阵光纤激光通过相干合成进行角度扫描的原理进行了研究。利用相干合成模型,用MATLAB分别对信号无噪声与含有随机相位噪声时的合成效果进行了数值仿真计算,分析了通过主动相位控制对合成光进行角度扫描的可行性;基于MOPA结构光纤激光线列搭建了相干合成角度扫描控制系统。通过实验验证了在多路光纤激光完成锁相后,若依次等比改变各芯激光的相位可以实现主极大条纹连续的角度扫描,扫描范围与模型中计算所得结果基本一致,实验结果与理论计算相符。该方法的探索研究对线列光纤激光的相干合成应用拓展有一定的指导意义。

Laser beam combining technique allows increasing the power of laser radiance far beyond what is obtained from a single conventional laser.Moreover,this technique is also able to control the far-field laser combining intensity distribution.Based on the theory,the principle of coherent combining of lasers from multi-core linear fiber array was studied.By using the coherent synthesis model,the coherent combining effect of multi-core linear fiber array was numerically simulated by MATLAB when wavefront of the lasers with and without random phase noise respectively,and the feasibility of angle scanning using actively phase-controlling was analyzed.The coherent combining angle scanning control system was built based on MOPA laser linear array fibers.The experiment shows that active phase-controlling of the laser linear array is able to realize the angle scanning of the main maximal stripe,and the scanning range is between two secondary large stripes.The experimental results are consistent with the theoretical calculation,and that has a guiding significance to the application of coherent combining of linear fiber array lasers.