Sample phase gradient and fringe phase shift in dual phase grating X-ray interferometry

Aimin Yan; Xizeng Wu; Hong Liu

doi:10.1364/oe.27.035437

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arXiv · 1906.08833

Sample phase gradient and fringe phase shift in dual phase grating X-ray interferometry

Aimin Yan·Xizeng Wu·Hong Liu

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Abstract

One of the key tasks in grating based x-ray phase contrast imaging is to accurately retrieve local phase gradients of a sample from measured intensity fringe shifts. To fulfill this task in dual phase grating interferometry, one needs to know the exact mathematical relationship between the two. In this work, using intuitive analysis of the sample-generated fringe shifts based on the beat pattern formation mechanism, the authors derived the formulas relating sample's phase gradients to fringe phase shifts. These formulas provide also a design optimization tool for dual phase grating interferometry.

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Aimin Yan, Xizeng Wu, Hong Liu. 2019-06-20. Sample phase gradient and fringe phase shift in dual phase grating X-ray interferometry. https://doi.org/10.1364/oe.27.035437

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