基于白光干涉测量色散补偿薄膜的群延迟色散

为精确测量超快激光色散补偿薄膜的群延迟色散,提出了一种基于窗口傅里叶变换和样条插值去噪算法的新型白光干涉测量方案。计算机模拟表明此方法测试精度可达0.58fs2。分析了高斯噪声和光强平均效应对测试精度的影响,并使用此方法对实验制备的Gires-Tournois干涉反射镜和啁啾镜进行了测试,在宽光谱范围内测试误差小于10fs2。该方法相比其他算法可以更快速、更精确地实现薄膜相位信息的提取,具有更高的测试精度和实用性。

Measurement of Group Delay Dispersion of Dispersive Mirror Based on White-Light Interference

A novel white-light interferometric method based on window Fourier transform and cubic spline interpolation algorithm is proposed for accurate measurement of group delay dispersion of dispersive mirror applied in ultrafast laser system. Numerical simulations indicate that the proposed method exhibits precision up to 0.58 fs2. After analyzing the effect of Gaussian noise and averaging effect of light intensity on the test accuracy of the above method, home-made Gires-Tournois interferometer mirrors and chirped mirrors are measured. The experimental results demonstrate that group delay dispersion errors are less than 10 fs2 in a wide spectral range. It is concluded from numerical simulations and experimental results that the proposed method can obtain phase information of thin films correctly and quickly, and it is more precise and practical than other algorithms.