自干涉非相干全息成像系统分辨率

Imaging Resolution of Self-Interference Incoherent Digital Holographic System

基于拉格朗日不变量法则,与经典光学成像系统分辨率对照,分别对自干涉非相干数字全息(SIDH)成像系统的横向以及轴向分辨率展开讨论。通过系统放大率及点扩展函数半峰全宽的计算,从理论上给出系统横向和轴向分辨率,以及系统分辨本领判断准则的具体数学表达式。并与经典光学成像系统对比,指出当全息记录面位于来自物光点的两束球面光波光斑的完全重合处时,自干涉非相干全息成像系统的横向超分辨率提高了一倍。引入压缩感知数值重构算法改善系统轴向分辨率,并给出相应的数值模拟及实验结果。研究结果对自干涉非相干数字全息术在成像、测量以及光路设计方面具有重要的指导意义。

Based to the Lagrange invariant law, the lateral and axial imaging resolution of self-interference incoherent digital holography （SIDH） imaging system is discussed in detail, comparing with the resolution of classical optical imaging system. The mathematical expression for the lateral, axial imaging resolution and the resolution capability criterion are presented in theory, according to the system magnification and the full-width at half-maximum of the point spread function. It indicates that the SIDH can improve the lateral resolution of one time when the hologram is recorded at the position, and the two spherical waves from the object point are perfectly overlapped, comparing with the classical coherent optical imaging systems. The compression sensing numerical reconstruction algorithm is introduced to improve the axial resolution of system, and the corresponding numerical simulation and experimental results are obtained. The analysis results have important guiding significance for SIDH in imaging, measurement and optical system design.