提出了一种实现大行程飞秒激光脉冲对相位控制的方法。其设计思想是：在迈克耳孙干涉仪中,利用改变激光偏振态的方法改变输出两光束的光程差因子。在对He-Ne激光输出的两束光实现相位锁定的基础上,进而提出了一种可对于超短激光双脉冲相对相位差实现超大行程控制的方法。对He-Ne激光的动态相位锁定、以及飞秒激光脉冲对的相对相位差控制分别作了实验验证。对He-Ne激光的静态相位锁定结果表明干涉仪两臂光程差可以控制在纳米精度;而飞秒激光脉冲测量自相关曲线与理论拟合结果非常接近,经傅里叶变换可得到较好的单峰谱图。该系统能够在实验范围中几乎无行程限制地实现飞秒激光脉冲对的相对相位动态稳定控制。

A phase control method of femtosecond laser pulse pair over a large range is presented, which is based on the assumption that change of the laser polarization state affects the optical path difference factor of the two beams in the Michelson interferometer. Based on the phase locking of the two beams from the He-Ne laser, the relative phase difference control for femtosecond laser pulse pair is achieved over a large range. The dynamic phase locking for the beam from the He-Ne laser and the relative phase difference control for femtosecond laser pulse pair are validated experimentally. The former experimental result shows that the optical path difference of the two arms is controlled within nanometer scale. The measured autocorrelation curve of the femtosecond laser pulse fits the theoretical result well, and the Fourier transform shows a single-peak spectrum. The system can steadily achieve the relative phase difference dynamic control of the femtosecond laser pulse pair almost without limitation of range.