离轴八程放大器自动准直技术研究

Automated alignment research on off-axis eight-pass laser amplifier

展示了基于离轴八程激光放大器的闭环自动准直技术研究,该项技术旨在用自动准直系统取代手动光路准直的方式,明显提高了该构型复杂的多程激光放大器的运行效率、准直精度与其输出光束质量。该技术利用主激光照明和像传递系统实现离轴八程激光放大器中滤波器小孔空间位置的精确标定,通过边缘检测处理远场光斑得到其指向中心。基于光斑中心与基准间的差值,对特定反射镜架进行二维控制进行光束指向补正,从而实现离轴八程放大器系统的闭环自动准直。研究结果表明,实验结果契合离轴八程放大器系统对光束准直准确率与效率的要求,验证了该准直技术在离轴八程激光放大光路中应用的可行性。

We present a technical research experimentally demonstrating automated alignment on off-axis eightpass laser amplifier.The mentioned technique aims to replace manual alignment method with automatic alignment system on the multipass complex laser amplifier,of which the efficiency,accuracy,and output beam quality would improve spectacularly.This technique realizes precise reference mark of pinhole spatial centre position in the spatial filter of the off-axis eight-pass laser amplifier via main laser lighting and image relaying system.The far-field facula is processed by edge detection so that the beam pointing centre is obtained.Based on the difference between the beam centre position and reference,we realizes closed loop automated alignment on the amplifier system via twodimensionally controlling specific reflector frames.Additionally we indicate that the experimental results of the research fairly satisfied requirements for efficiency and accuracy of the off-axis eight-pass laser amplifier,and verified feasibility of the alignment technique applied in the amplifier as well.