单链路光束波前畸变对相干合成系统相位控制的影响

Influence of Wavefront Distortion in Single Laser Channel on Phase Control in Coherent Beam Combination System

利用相位型空间光调制器产生可控波前畸变,对单链路光束波前畸变对相干合成系统相位控制的影响进行了实验研究。结果表明,当波前畸变均方根(RMS)较小(小于π/10)时,相位控制系统性能基本不受波前畸变的影响。随着波前畸变均方根值的增大,远场条纹逐渐发生不同程度的漂移,相位控制系统不再能够完全锁定各光束的相位,存在一定的相位控制残差。当波前畸变均方根值大于等于π时,相位基本不能被锁定,相位控制系统失效。实验结果对相位控制系统的影响对相干合成高能激光系统的工程实践具有参考价值。

Phase-only spatial light modulators are employed to generate controllable wavefront distortion,which is incorporated into a coherent beam combining system to investigate the influence of wavefront distortion in single laser channel on phase control system.Experimental results show that the phase control system is almost not affected in the case of wavefront distortion with small root mean square（RMS） value（i.e.,RMSπ/10）.As an increase in the wavefront distortion,the optical phase cannot be totally controlled,residual phase error goes with excursion in the interference patterns exists in the system.When the RMS value of the wavefront distortion is as large as π,the phase control system is in invalidation state and the beamlets cannot be phase locked.Our experimental results present reference for designing and manufacturing high energy laser system based on coherent beam combining.