基于周期阵列抽样孔的非迭代实时相干衍射成像  

Noniterative real-time coherent diffraction imaging by period sampling aperture array

作　　者：魏功祥[1] 国承山[2] 张新廷[2] 付圣贵[1] 

机构地区：[1]山东理工大学理学院,淄博255049 [2]山东师范大学物理与电子科学学院,济南250014

出　　处：《中国科学：物理学、力学、天文学》2012年第5期452-457,共6页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金资助项目(批准号:11074152和11104165)

摘　　要：提出了一种从远场衍射强度图样实现实时相干衍射成像的迭代方法.该方法利用特殊设的周期正方阵列抽样针孔对待测物体的涅耳衍射场的波前进行抽样,用CCD录其远场衍射图样.算机中对其处理,可以直接从远场衍射图样的逆里叶变换中提取物波的抽样振幅数据,利用标量衍射理论对物体重现.因为该方法只需要对一幅远场衍射图样进行测量,避免了迭代算法,而且从理论上不需要透镜,它可以较广的波长范围内实现实时相干衍射成像.A noniterative method for real-time coherent diffraction imaging from a far-field diffraction intensity measurement in a coherent wave field is proposed. In this method, the wave field of an object after Fresnel diffraction is sampled by a special designed square aperture array plate, and its far field diffraction intensity is recorded by a CCD. The sampled complex amplitude can be directly retrieved from the inverse Fourier transform of the far field diffraction pattern. Coherent diffraction imaging can be accomplished by inverse diffract to the object plane in computer.The aperture array plate is consisting of two dimensional （2D） period sampling aperture array （PSAA）. As this method requires only a single measurement of the diffraction intensity pattern and does not need any iterative algorithm and lens systems in principle, it provides a practically valuable approach for real-time imaging of a complex-valued object in a wide range of wavelengths.

关 键 词：相干衍射成像 远场衍射 相位恢 周期阵列抽样针孔 里叶变换 

分 类 号：O436.1[机械工程—光学工程]