ORCID Profile
0000-0002-5748-9295
Current Organisation
University of Adelaide
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Publisher: AIP Publishing
Date: 2023
DOI: 10.1063/5.0168156
Publisher: Optica Publishing Group
Date: 23-12-2022
DOI: 10.1364/OE.474794
Abstract: Wavefront-marking X-ray imaging techniques use e.g., sandpaper or a grating to generate intensity fluctuations, and analyze their distortion by the s le in order to retrieve attenuation, phase-contrast, and dark-field information. Phase contrast yields an improved visibility of soft-tissue specimens, while dark-field reveals small-angle scatter from sub-resolution structures. Both have found many biomedical and engineering applications. The previously developed Unified Modulated Pattern Analysis (UMPA) model extracts these modalities from wavefront-marking data. We here present a new UMPA implementation, capable of rapidly processing large datasets and featuring capabilities to greatly extend the field of view. We also discuss possible artifacts and additional new features.
Publisher: SAGE Publications
Date: 26-10-2023
Publisher: Optica Publishing Group
Date: 02-03-2020
DOI: 10.1364/AO.384531
Abstract: X-ray phase-contrast techniques are powerful methods for discerning features with similar densities, which are normally indistinguishable with conventional absorption contrast. While these techniques are well-established tools at large-scale synchrotron facilities, efforts have increasingly focused on implementations at laboratory sources for widespread use. X-ray speckle-based imaging is one of the phase-contrast techniques with high potential for translation to conventional x-ray systems. It yields phase-contrast, transmission, and dark-field images with high sensitivity using a relatively simple and cost-effective setup tolerant to ergent and polychromatic beams. Recently, we have introduced the unified modulated pattern analysis (UMPA) [ Phys. Rev. Lett. 118 , 203903 ( 2017 ) PRLTAO 0031-9007 10.1103/PhysRevLett.118.203903 ], which further simplifies the translation of x-ray speckle-based imaging to low-brilliance sources. Here, we present the proof-of-principle implementation of UMPA speckle-based imaging at a microfocus liquid-metal-jet x-ray laboratory source.
Publisher: AIP Publishing
Date: 2023
DOI: 10.1063/5.0168888
Publisher: Public Library of Science (PLoS)
Date: 29-08-2022
DOI: 10.1371/JOURNAL.PONE.0273315
Abstract: X-ray directional dark-field imaging is a recent technique that can reveal a s le’s small-scale structural properties which are otherwise invisible in a conventional imaging system. In particular, directional dark-field can detect and quantify the orientation of anisotropic structures. Here, we present an algorithm that allows for the extraction of a directional dark-field signal from X-ray speckle-based imaging data. The experimental setup is simple, as it requires only the addition of a diffuser to a full-field microscope setup. Sandpaper is an appropriate diffuser material in the hard x-ray regime. We propose an approach to extract the mean scattering width, directionality, and orientation from the recorded speckle images acquired with the technique. We demonstrate that our method can detect and quantify the orientation of fibres inside a carbon fibre reinforced polymer (CFRP) s le within one degree of accuracy and show how the accuracy depends on the number of included measurements. We show that the reconstruction parameters can be tuned to increase or decrease accuracy at the expense of spatial resolution.
Location: United Kingdom of Great Britain and Northern Ireland
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for Ronan Smith.