对光克尔脉冲净化器中，不同双折射度光纤中相干耦合效应对光克尔脉冲净化器透射率以及输出脉冲的时间波形、光谱以及脉冲自身透射率等特性进行了模拟分析。结果表明：高双折射光纤中，两偏振光的相干耦合效应影响可以忽略；普通单模光纤中两偏振光的相干耦合导致透射率幅值变化在±1%左右；低双折射光纤中相干耦合效应影响较大，且相干耦合效应对输出脉冲时间波形与光谱以及脉冲自身透射率曲线都有一定影响。

We use a transient-grating (TG) process in a Kerr bulk medium to clean a femtosecond laser pulse. Using the technique, the temporal contrast of the generated TG signal is improved by more than two orders of magnitude in comparison with the incident pulse in a 0.5-mm-thick fused silica plate. The laser spectrum is smoothed and broadened, and the pulse duration is shortened simultaneously. We expect to extend this technique to a clean pulse with broadband spectral bandwidth at a wide spectral range because it is a phase-matched process.