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Updated: Jul 18, 2026

A Method for Tracking the Time Evolution of Steady-State Evoked Potentials
Published on: May 25, 2019
Effectiveness of iterative algorithms in recovering phase in the presence of noise
Garth Williams1, Mark Pfeifer, Ivan Vartanyants
1Department of Physics, University of Illinois, Urbana, IL 61801, USA. g.williams@physics.unimelb.edu.au
Abstract:
Inversion of coherent X-ray diffraction patterns allows the imaging of three-dimensional density distributions. The recovery of such shapes often requires application of iterative algorithms, such as Fienup's error reduction or hybrid input/output. Since the measurement of such a pattern records the intensity in reciprocal space, any errors due to noise will probably not have a straightforward impact on the final real-space result. In this paper, the effect of the types of noise common in coherent X-ray diffraction (CXD) experiments, counting statistics, scatter from alien particles and detector noise, on the recovered real-space density projection is explored by simulating a two-dimensional CXD pattern and adding noise. It is found that an R factor measuring the reproducibility between the best and second-best real-space result is a leading indicator of performance.
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