单幅自干涉非相干同轴全息重建

Reconstruction of single-shot on-axis self-interference incoherent hologram

为解决离轴自干涉非相干数字全息(SIDH)图由于受到包络函数的调制使得其再现像质量远低于同轴全息图这一问题,提出基于单幅同轴SIDH图的压缩感知(CS)重建方法。首先建立与SIDH的光学记录和再现物理过程相适应的传感矩阵,从理论构建数值重建算法框架;然后,基于SIDH光路,以多个离散点源、LED和分辨率板作为待测物,分别进行计算机数值模拟及实验研究。研究结果表明,与传统反向传播重建方法相比,本文重建方法可基于单幅同轴SIDH图进行数值重构,并有效抑制孪生像及自相关成分信息的干扰;与采用4幅全息图进行计算的相移法相比,采样数据为原来的25%,而且本文方法得到的再现光场与采用四步相移法相比得到再现光场的相关度高达0.97;与目前离轴光路记录的SIDH再现结果相比,再现像质量得到大幅度的提高。

A numerical reconstruction method by compressive sensing （CS） for single-shot on-axis self-in- terference incoherent hologram is proposed. Firstly, the sensing operator is built up based on the physical mechanism of self-interference incoherent digital holography （SIDH）. And then,the recovery method by enforcing the two-step iterative shrinkage-thresholding algorithm is employed for the reconstruction. Nu- merical simulations and experiments employing several discrete source points,light-emitting diode （LED） and resolution target are performed to demonstrate the feasibility and validity of the method. Analysis resuits indicate that, compared with the back-propagation method, the object field can be reconstructed based on single-shot on-axis self-interference incoherent hologram by the proposed method with the out- of-focus twin image and the autocorrelation term information inhibited. Compared with the four-step phase shifting method, there is just 25 % sampled data, and the correlation coefficient of the reconstructed image by the proposed method and that by phase shifting method is 0. 97. Furthermore,the quality of the reconstructed image is improved greatly compared with single-shot self-interference incoherent digital holography using off-axis configuration.