考虑激光脉冲啁啾放大与压缩技术要求脉冲压缩光栅有较低的像差, 设计并制作了一个小形变变形镜来补偿大口径光栅基板加工残余的亚微米级静态像差对光栅波像差的影响。 该变形镜有效口径为80 mm、厚度为5 mm, 包含19个分立式压电促动器。采用干涉仪测量得到各个促动器的响应函数, 构建了变形镜的刚度矩阵; 采用最小二乘法求解出获得目标面形时各个促动器上所需施加的控制电压; 通过整体优化和局部优化的结合, 使变形镜的目标面形得到了有效控制。应用该变形镜构建了主动式全息光学记录系统, 并选用具有较大像差的基板开展了光栅像差补偿实验。实验显示, 对残余像差为~0.93λ的基板, 采用变形镜后制作出了残余波面PV可达0.14λ(@ 633 nm)的脉冲压缩光栅, 验证了小形变变形镜在光栅基底像差补偿上的有效性。

To realize the low aberration of pulse compression gratings (PCGs) applied in chirped pulse amplification and compression, a Deformable Mirror (DM) with small deformation was designed and fabricated to compensate the sub-micron static wavefront aberration induced by a large diameter grating substrate. The DM contains 19 piezoelectric actuators and its effective diameter is 80 mm and thickness is 5mm. The response function of each actuator was measured with an interferometer to construct the stiffness matrix of the DM. The least square was used to resolve the control voltage required of each actuator to obtain the target surface. By combination of the global optimization and local optimization, the target surface of the DM was controlled effectively. Finally, the DM was used to construct an active holographic optical recording system and a substrate with bigger aberration was selected to perform the compensation experiment for the grating. The experimental results show that: for about 0.93λ aberration of grating substrate, the PV of residual wave-front aberration of the PCG is near to 0.14λ (@ 633 nm) after employing the DM. It demonstrates that the DM can be effectively applied in the fabrication of low aberration PCGs.