Pixellated CdZnTe detector for emission/transmission computed tomography

A small pixellated CdZnTe array is tested for suitability in a prototype SP ECT system designed to acquire both emission and transmission data. Determi ning the optimum contact design and obtaining performance estimates of sing le photon acquisition are the primary focus. Flood field and collimated Co- 57 sources irradiated the 16 pixel array (5 mm thick and 1.5 mm pixels) to determine photopeak efficiencies and detector response with different event collection techniques. intrinsic full energy peal; efficiency averaged 72% for an 18 keV acceptance window. A small irradiation spot scanned an array region, revealing detector response from nearby pixels. Post processing sp ectra compare coincident and anti-coincident acquisition. Additionally, cur rent mode tests compare linearity with a CdWO4/Si p-i-n detector. (C) 1999 Published by Elsevier Science B.V. All rights reserved.