Speakers
Vittorio di Trapani
Speckle-based imaging (SBI) is an X-ray phase-contrast imaging (XPCI) technique that provides access to phase and small-angle-scattering (or dark-field) signals, in addition to the attenuation signal achieved with conventional approaches. To retrieve the phase and dark-field signals, SBI uses random wavefront markers, such as simple sandpapers, to generate speckles at the detector. As for other XPCI techniques, SBI was first pioneered using synchrotron radiation. When translating the technique from synchrotron sources to compact laboratory setups, the reduced coherence of the source and limitations in the available resolution yield lower speckle visibility, thus hampering the retrieval of the phase and dark-field signals. Here, we present a newly established OPTimal IMAging and TOmography (OPTIMATO) laboratory for X-ray imaging hosted at the Elettra synchrotron (Trieste, Italy). The presented setup includes a micro-focus high-brilliance liquid-metal jet source that emits X-rays on two opposite sides. Two semi-independent branches featuring maximum source-detector distances of 2m and 4m have been implemented. The short branch is devoted to high-resolution imaging with resolutions below 1μm, whereas the long branch is mainly dedicated to SBI with resolutions up to 15μm. Summarizing the main limiting factors when moving SBI applications from synchrotron facilities to compact laboratory setups, we present the challenges in the design of the laboratory setup and the first SBI images obtained at the OPTIMATO laboratory.
Originally from Palermo (Italy), Dr. Di Trapani completed a bachelor’s degree in Physics (2015) and a Master’s degree in Medical Physics (2017) at the University of Pisa (Italy). His Master’s thesis concerned the characterization of a system for propagation based system for breast CT with synchrotron radiation implemented within the SYRMA-3D collaboration at the SYRMEP beamline of the Elettra synchrotron (Trieste, Italy). In 2017, he started a PhD in Experimental Physics at the University of Siena (Italy). His Ph.D. project focused on the implementation of two state-of-the-art acquisition systems for spectral imaging applications: (i) a laboratory setup for spectral micro-CT with an energy-resolving photon-counting detector, and (ii) a setup for K-edge imaging with bent-Laue optics with synchrotron sources. As part of his Ph.D. program, he spent six months as a visiting researcher at the University of Saskatchewan (Saskatoon, Canada), under the supervision of Prof. D. Chapman, working on the development of acquisition procedures and reconstruction algorithms tailored for spectral imaging with bent-Laue crystals. After defending his Ph.D. thesis, in July 2021 he joined the S-BaXIT project (ERC consolidator grant project led by Prof. P. Thibault) as a Postdoctoral Fellow. In the framework of the project, he worked on the design and implementation of a new laboratory facility for X-ray imaging (tomography, spectral imaging, propagation-based imaging, and speckle-based imaging) hosted by the Elettra Synchrotron. His main interests include X-ray detectors, spectral imaging applications, and the development of phase contrast techniques.