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arXiv · 2211.11757

Directional dark-field retrieval with single-grid x-ray imaging

Michelle K Croughan·Ying Ying How·Allan Pennings·Kaye S Morgan
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Abstract

Directional dark-field imaging is an emerging x-ray modality that is sensitive to unresolved anisotropic scattering from sub-pixel sample microstructures. A single-grid imaging set-up can be used to capture dark-field images by looking at changes in a grid pattern projected upon the sample. By creating analytical models for the experiment, we have developed a single-grid directional dark field retrieval algorithm that can extract dark-field parameters such as the dominant scattering direction, and the semi-major and -minor scattering angles. We show that this method is effective even in the presence of high image noise, allowing for low dose and time sequence imaging.

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Michelle K Croughan, Ying Ying How, Allan Pennings, Kaye S Morgan. 2022-11-21. Directional dark-field retrieval with single-grid x-ray imaging. https://doi.org/10.1364/oe.480031

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