Quantum mechanics

Phase (matter)

Speckle pattern

Tracking (education)

Pedagogy

Computer science

Phase contrast microscopy

Phase-contrast imaging

Thermodynamics

Physics

Psychology

Optics

Speckle imaging

Artificial intelligence

Sample (material)

Computer vision

Synchrotron radiation

Physical review. A/Physical review, A

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.

Single-image geometric-flow x-ray speckle tracking