Object Initialization For Ptychographic Scans With Reduced Overlap

Felix Wittwer; Peter Modregger

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arXiv · 2207.13760

Object Initialization For Ptychographic Scans With Reduced Overlap

Felix Wittwer·Peter Modregger

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Abstract

X-ray ptychography utilizes overlapping illuminations to reconstruct the object's phase and absorption signal with spatial resolutions much smaller than the focus size. Usually, the illumination overlap is chosen to be between 50% and 60% in order to ensure high quality reconstructions at reasonable scan times and/or doses. Here, we experimentally demonstrate that ptychographic iteration with object instead of flat initialization allows for a significant reduction of the overlap with only a modest loss in reconstruction quality. This approach could prove beneficial for dose sensitive experiments and for rapid feedback overview scans.

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Felix Wittwer, Peter Modregger. 2022-07-27. Object Initialization For Ptychographic Scans With Reduced Overlap. https://arxiv.org/abs/2207.13760

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