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arXiv · 2603.14555

Retrieval of multiple fibre orientations using X-ray dark-field signal modelling

Lorenzo Massimi·Michela Fratini·Shashidhara Marathe·Christoph Rau·Giuseppe Gigli·Alessandro Olivo·Alessia Cedola
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Abstract

Dark-field imaging is widely used to infer fibre orientation from signal modulation as a function of sample orientation. However, current X-ray dark-field retrieval methods are restricted to single orientations and require tomography to resolve overlapping structures. This approach is time-consuming and not suitable for thin materials, which are common in materials science. Here we present a dark-field model capable of retrieving multiple fibre orientations within a single pixel. The model, based on a geometrical description of fibre scattering, was validated through Monte Carlo simulations and experiments using beam-tracking setups with 1D and 2D masks. Results demonstrate reliable orientation retrieval for up to two fibres per pixel, with the 2D mask providing multi-directional sensitivity in a single acquisition and enabling faster and simplified data collection.

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Lorenzo Massimi, Michela Fratini, Shashidhara Marathe, Christoph Rau, Giuseppe Gigli, Alessandro Olivo, Alessia Cedola. 2026-03-15. Retrieval of multiple fibre orientations using X-ray dark-field signal modelling. https://arxiv.org/abs/2603.14555

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