Jun 3 – 5, 2022
Parador El Saler, Valencia, Spain
Europe/Zurich timezone

Toward a First Prototype Time-of-flight CT Scanner

Jun 3, 2022, 1:05 PM
Parador El Saler, Valencia, Spain

Parador El Saler, Valencia, Spain

Fast X-ray imaging Fast X-Ray imaging


Julien Rossignol (Université de Sherbrooke)


Recent developments have shown the potential of a time-of-flight measurement of individual photons using fast X-ray detectors to significantly reduce the adverse effects of scattered photons both in X-ray radiography and computed tomography (CT) without using anti-scatter grids. However, the improvements observed in simulations have yet to be confirmed experimentally using a system realistic for clinical use. Producing a first CT image with real-time discrimination of scattered photons requires an ultrafast single X-ray counting system and an ultrashort pulsed X-ray source. This contribution focuses on the design and preliminary characterization of a 16-channel scintillator-based scanner. The detector is composed of 16 4x4x2.5 mm3 LYSO scintillators coupled with 16 4x4 mm2 SiPMs from Broadcom (AFBR-S4N44C013). A Nino pre-amplifier and two time-to-digital converters designed in-house read the SiPMs’ output to provide time and energy measurements using time-over-threshold. GATE simulations have shown that if a 200 ps time resolution is obtained, this system will be able to remove half of the scattered photon, resulting in a 20% increase in CNR. This system will be used to improve our understanding of time-of-flight scatter rejection and evaluate scintillators for fast X-ray measurements.

Primary authors

Julien Rossignol (Université de Sherbrooke) Mr Philippe Marcoux (Université de Sherbrooke) Mr Gabriel Bélanger (Université de Sherbrooke) Frédéric Gagnon (Université de Sherbrooke) Mr Patrick Dufour (Université de Sherbrooke) Prof. Audrey Corbeil Therrien (Université de Sherbrooke) Prof. Yves Bérubé-Lauzière (Université de Sherbrooke) Prof. Réjean Fontaine (Université de Sherbrooke)

Presentation materials