用单幅数字全息和剪切干涉原理重构光场相位

Reconstructing the Phase of Wavefront Using Digital Hologram and the Principle of Shearing Interferometry

全息干涉计量和剪切干涉计量都是光学测量的重要方法,但似乎一直在独立发展。数字全息可以数字化地再现光场,而剪切干涉从原理上讲只需将光场做一定剪切后再相互干涉即可,于是将剪切干涉的原理引入到数字全息再现光场的重构中,通过将数字全息再现光场做人为平移实现剪切干涉,得到几乎没有包裹的剪切相位分布,有利于相位计算。在理论分析的基础上,给出了基于最小二乘原理的相位重构算法。通过模拟计算和实验验证,证明了该方法的可行性和有效性。结果表明,使用该方法得到的相位更接近实验值,能得到比传统方法更好的计算结果。

Both holographic interferometry and shearing interferometry are important methods in optical measurement but they are developed independently.Digital hologram can reconstruct wavefront numerically,and shearing interferometry essentially is the interference of a coherent wavefront with a copy of itself ＂sheared＂ or translated by a distance,so the principle of shearing interferometry can be applied to reconstruct the wavefront of digital hologram.By shearing numerical wavefront,several pixels to obtain few wrapped shearing phase will make the phase calculation easy.Based on theoretical analyses and the least-square principle,the algorithm of constructing wavefront is presented.Simulated and experimental results show the validity and feasibility of the presented algorithm.The obtained phase approaches experimental value well and is better than the results of conventional methods.