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arXiv · 2404.14584

X-ray Interferometry Using a Modulated Phase Grating: Theory and Experiments

Hunter Meyer·Joyoni Dey·Sydney Carr·Kyungmin Ham·Leslie G. Butler·Kerry M. Dooley·Ivan Hidrovo·Markus Bleuel·Tamas Varga·Joachim Schulz·Thomas Beckenbach·Konradin Kaiser
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Abstract

X-ray grating interferometry allows for the simultaneous acquisition of attenuation, differential-phase contrast, and dark-field images, resulting from X-ray attenuation, refraction, and small-angle scattering, respectively. The modulated phase grating (MPG) interferometer is a recently developed grating interferometry system capable of generating a directly resolvable interference pattern using a relatively large period grating envelope function that is sampled at a pitch that allows for X-ray spatial coherence using a microfocus X-ray source or by use of a source G0 grating that follows the Lau condition. We present the theory of the MPG interferometry system for a 2-dimensional staggered grating, derived using Fourier optics, and we compare the theoretical predictions with experiments we have performed with a microfocus X-ray system at Pennington Biomedical Research Center, LSU. The theoretical and experimental fringe visibility is evaluated as a function of grating-to-detector distance. Quantitative experiments are performed with porous carbon and alumina samples, and qualitative analysis of attenuation and dark-field images of a dried anchovy are shown.

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Hunter Meyer, Joyoni Dey, Sydney Carr, Kyungmin Ham, Leslie G. Butler, Kerry M. Dooley, Ivan Hidrovo, Markus Bleuel, Tamas Varga, Joachim Schulz, Thomas Beckenbach, Konradin Kaiser. 2024-04-22. X-ray Interferometry Using a Modulated Phase Grating: Theory and Experiments. https://doi.org/10.1038/s41598-024-78133-8

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