详细探究了平行相位调制(PPM)算法在飞秒激光脉冲的频谱相位测量与补偿中的应用。通过数值模拟讨论了调制频率选取和相位复原问题。基于该算法搭建了一套飞秒激光脉冲整形装置,使用自行编写的LabVIEW程序完成频谱相位的测量补偿过程,并使用多光子脉冲内干涉相位扫描(MIIPS)方法验证了实验结果的准确性。不同于MIIPS等已有超快激光脉冲测量方法,PPM法无需测量非线性信号的光谱,只需测量信号强度即可快速确定频谱相位。
The parallel phase modulation (PPM) algorithm is investigated for spectral phase measurement andcompensation. Detailed theoretical analysis and a numerical simulation are carried out to find how to determine themodulation frequency and reconstruct the spectral phase. A femtosecond pulse shaper is set up based on the PPMalgorithm. The shaper is driven by our home-developed LabVIEW program and can be used to measure andcompensate spectral phase of femtosecond pulses. The experimental results are verified with the multi-photon intra-pulse interference phase scan (MIIPS) method. Different from such existing ultrafast pulse measurement methodsas MIIPS, the PPM method only needs to measure the signal intensity to determine the spectral phase quickly, andrequires no spectrum measurements of nonlinear signals.