高展宽量八通展宽器的设计制作

Design and Experiment of 8-Pass Laser Pulse Stretcher

在啁啾脉冲放大(CPA)技术中,提高展宽器的展宽量能有效地提高激光器的输出能力,而展宽器的展宽量与其构型及参数设计紧密相关,因此可以通过构型的选取及参数的优化来提高展宽器的展宽量。用光线追迹法导出了单光栅单透镜展宽器构型的设计解析式,利用这些解析式可以进行展宽器参数的优化,在此基础上设计制作了高展宽量的八通展宽器,并利用所研制的展宽器,将中心波长为1053 nm的93 fs脉冲展宽到4.35 ns。在该构型展宽器中,通过控制焦平面反射镜处的光强分布可以较方便地进行光谱整形,在实验中得到了和声光色散滤波器整形后类似的中心凹陷的波形。

In a chirped pulse amplification （CPA） laser facility, the output capability can be increased if the pulse can be stretched wider. Adopting the design of ＂single-grating and single-lens＂, a 8-pass laser pulse stretcher is developed, and analytical formulae about the design are presented, with which the stretcher has been optimized to some extend. With the stretcher which has been developed, a pulse of 93 fs is stretched to 4.35 ns. Additionally, by controlling the reflection of the mirror in the focal plate （or controlling transmission of an optical component before the mirror）, a shaped pulse can be obtained, which is similar to the pulse gotten from an acoustic-optic programmable dispersion filter （AOPDF）.