Chromatic X-Ray imaging with a fine pitch CdTe sensor coupled to a large area photon counting pixel ASIC

摘要

An innovative X-ray imaging sensor with intrinsic digital characteristics ispresented. It is based on Chromatic Photon Counting technology. The detector isable to count individually the incident X-ray photons and to separate themaccording to their energy (two 'color' images per exposure). The energyselection occurs in real time and at radiographic imaging speed (GHz globalcounting rate). Photon counting, color mode and a very high spatial resolution(more than 10 l.p./mm at MTF50) allow to obtain an optimal ratio between imagequality and absorbed dose. The individual block of the imaging system is atwo-side buttable semiconductor radiation detector made of a thin pixellatedCdTe crystal (the sensor) coupled to a large area VLSI CMOS pixel ASIC. 1, 2,4, 8 tile units have been built. The 8 tiles unit has 25cm x 2.5cm sensitivearea. Results and images obtained from in depth testing of severalconfigurations of the system are presented. The X-Ray imaging system is thetechnological platform of PIXIRAD Imaging Counters s.r.l., a recentlyconstituted INFN spin-off company.