DETECTOR SHAPE AND ARRANGEMENT FOR POSITRON ANNIHILATION IMAGING DEVICE

摘要

ABSTRACT OF THE DISCLOSUREA circular array of detectors is used for detectingcoincident events and the point of annihilation in a positronannihilation process in a selected plane wherein the output fromthe detectors is processed in a computer to provide image recon-struction for the selected plane. Bismuth germanate is shownto be more efficient than previously used detectors and theadaption of trapezoidal shape for the detectors enables moreefficient utilization of the photons produced in the process.The use of absorbing metal reducing plugs between adjacent de-tectors may be used to decrease the aperture function of thedetectors for low angles of incident radiation.