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arXiv · 1808.00456

Single-Image Geometric-Flow X-Ray Speckle Tracking

David M. Paganin·Helene Labriet·Emmanuel Brun·Sebastien Berujon
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Abstract

We develop a speckle-tracking method for x-ray phase-contrast imaging, based on the concept of geometric flow. This flow is a conserved current associated with deformation of illuminating x-ray speckles induced by passage through a sample. The method provides a rapid, efficient, and accurate algorithm for quantitative phase imaging. It is highly photon efficient and able to image dynamic objects, since a single radiograph of the sample is sufficient for the phase recovery. We experimentally quantify the resolution and contrast of the approach with both two-dimensional and three-dimensional phase-imaging applications using x-ray synchrotron radiation. Finally, we discuss adaptations of the method to imaging with compact x-ray sources that have a large source size and significant spectral bandwidth.

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David M. Paganin, Helene Labriet, Emmanuel Brun, Sebastien Berujon. 2018-08-01. Single-Image Geometric-Flow X-Ray Speckle Tracking. https://doi.org/10.1103/physreva.98.053813

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