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Title: Coherent diffractive imaging and partial coherence

Abstract

We formulate coherent diffractive imaging in the framework of partially spatially coherent diffraction. We find that the reconstruction can be critically dependent on the degree of coherence in the illuminating field and that even a small departure from full coherence may invalidate the conventional assumption that a mapping exists between an exit surface wave of finite support and a far field diffraction pattern. We demonstrate that the introduction of sufficient phase curvature in the illumination can overcome the adverse effects of partial coherence.

Authors:
; ;  [1];  [2]
  1. School of Physics, University of Melbourne, Victoria 3010 (Australia)
  2. Department of Physics, La Trobe University, Bundoora, Victoria 3086 (Australia)
Publication Date:
OSTI Identifier:
20957758
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevB.75.104102; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
62 RADIOLOGY AND NUCLEAR MEDICINE; DIFFRACTION; ILLUMINANCE; IMAGE PROCESSING; IMAGES; MAPPING; VISIBLE RADIATION; WAVE PROPAGATION

Citation Formats

Williams, Garth J., Quiney, Harry M., Nugent, Keith A., and Peele, Andrew G.. Coherent diffractive imaging and partial coherence. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.104102.
Williams, Garth J., Quiney, Harry M., Nugent, Keith A., & Peele, Andrew G.. Coherent diffractive imaging and partial coherence. United States. doi:10.1103/PHYSREVB.75.104102.
Williams, Garth J., Quiney, Harry M., Nugent, Keith A., and Peele, Andrew G.. Thu . "Coherent diffractive imaging and partial coherence". United States. doi:10.1103/PHYSREVB.75.104102.
@article{osti_20957758,
title = {Coherent diffractive imaging and partial coherence},
author = {Williams, Garth J. and Quiney, Harry M. and Nugent, Keith A. and Peele, Andrew G.},
abstractNote = {We formulate coherent diffractive imaging in the framework of partially spatially coherent diffraction. We find that the reconstruction can be critically dependent on the degree of coherence in the illuminating field and that even a small departure from full coherence may invalidate the conventional assumption that a mapping exists between an exit surface wave of finite support and a far field diffraction pattern. We demonstrate that the introduction of sufficient phase curvature in the illumination can overcome the adverse effects of partial coherence.},
doi = {10.1103/PHYSREVB.75.104102},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 10,
volume = 75,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2007},
month = {Thu Mar 01 00:00:00 EST 2007}
}
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  • A Fresnel coherent diffractive imaging experiment is performed using a pinhole as a test object. The experimental parameters of the beam curvature and coherence length of the illuminating radiation are varied to investigate their effects on the reconstruction process. It is found that a sufficient amount of curvature across the sample strongly ameliorates the effects of low coherence, even when the sample size exceeds the coherence length.
  • We demonstrate an algorithm that reconstructs the complex transmission function of an object from experimental X-ray diffraction data using partially coherent 1.4 keV X-rays that does not require a priori input of the coherence function. The quality of the reconstruction is significantly better than that obtained by assuming that the illumination is fully coherent. Our approach can be readily applied to diffraction imaging problems where a model for the spatial coherence can be assumed.
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  • No abstract prepared.