球面参考光波数字全息的一些特点分析及实验

对以球面波作为参考光记录数字全息图的采样和再现分离条件进行了详细的分析。推导出了同时满足采样和再现分离条件时，CCD及物体的横向尺寸、物体及参考光源至CCD的距离之间需要满足的关系式，证明了完全散射物体上复振幅在记录面上的叠加可以等效为一个点光源在记录面上产生的效果，进行了相应的实验研究。结果表明：数字全息术中采用球面参考光波可以比采用平面参考光波更容易满足采样和分离条件，并可以记录到更多的物体信息；在物体至CCD的距离固定的情况下，无透镜傅里叶变换全息术是优化的记录光路结构；散射物体比衍射物体的数字全息图更容易满足采样和分离条件。

Analysis of the Characteristics about the Digital Holography of the Spherical Reference Wave

Based on some detailed theoretic analysis about the recording sampling and reconstructing separation requirement for the digital holography of the spherical reference wave, the relationship fulfilling above requirement for the lateral size of the object and CCD, the distance between the object, CCD and the reference wave point source are deduced. In the recorded plane, it is proved that the superposed complex amplitude of the scattering object is equivalent to that of a point source. The theoretic analysis and experimental results show: Compared with the digital holography of the plane reference wave, it is easier for the digital holography of the spherical reference wave to fulfill the requirements recording sampling and reconstructing separation meanwhile, to record more object information. If the distance between the object and CCD is unchangeable, lensless Fourier holography is the optimum digital recording system in improving the resolution of reconstructing image and enlarging the size of the recording object. If the recording condition is same, it is more difficult to record the digital hologram of the scattering object than that of the diffracting object.