可消除光场畸变的物面平移横向剪切数字全息

Lateral Shearing Digital Holography with Objective Translation to Eliminate Optical Phase Aberration

提出了一种可根本消除各种光场畸变的横向剪切数字全息方法,采用三幅物面相互存在微小平移的数字全息图,通过波前差分来消除照明光和参考光引入的相位畸变,用横向剪切波前重构算法恢复待测物面三维数据。设计了一个反射式实验检测光路,光路中人为引进未知的波前畸变对该算法进行了实验验证。结果表明,在没有对物面和CCD记录面做严格方位校准,横向平移精度为0.01 mm,平移量为0.02 mm的条件下,标准相位的均方根误差约为λ14,分析了其误差来源,可用于超精密光学三维测量,有望减小光场畸变提高测量精度。

A lateral shearing digital holography to completely eliminate optical phase aberration is present.Based on three sequentially digital holograms by lateral translation, three phases are obtained from the holograms. The optical aberration is eliminated by subtracting the phases each other and two phase differences of the wavefront under test are obtained. Lastly, the objective three-dimensional phase without optical aberration is reconstructed through the phase differences based on Fourier expansion. An interferometer optical path in reflective configure is designed to demonstrate the proposed method. Two aberrational lenses are introduced into the path to produce unknown optical phase aberrations. The demonstration experiments are carried out without parallel calibration between the CCD plane and the test objective plane. In the experiments,the translation displacement is 0.02 mm with the translation resolution of 0.01 mm. The experimental results show that the root mean squared error is about λ 14 between the phase of the proposed method and the standard phase without aberration. The error sources are analyzed. The proposed lateral shearing digital holography can be used to ultra-precise optical measurement through eliminating optical phase aberration to increase the measurement resolution.