A Comparative Study of Iterative and Conjugate Gradient Methods for Phase Retrieval from Fresnel Images
نویسنده
چکیده
The efficiency of practical methods for phase retrieval from the intensity distribution in Fresnel (nearfield) images is investigated in the paraxial limit. The aim was to develop a robust and efficient algorithm for phase retrieval from aperiodic objects in the limit where phases may vary continuously by several multiples of 2ð across the sampled field. The equations for Fresnel propagation of a coherent wave from the object plane are well known, where the complex amplitude and phase distribution in the x-y plane at z is given by fz. Then we have fz = f ⊗ h and Fz = F H . (1)
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تاریخ انتشار 2001