Computed tomography appts. - with bismuth germanate scintillator crystals sepd. by thin opaque plates for better resolution

摘要

An X-ray source is moved about the test region and illuminates an array of closely-spaced bismuth germanate scintillator crystalls, each of thickness h, perpendicular to the receiving face, less than the width along the face in the scan direction. Thickness is pref. 2 mm and width 4-8 mm, and a plate of high atomic number and 5 mils thickness which is opaque to the radiation separates adjacent crystals to prevent dispersal of radiation between crystals, thus improving resolution. The crystals are not hygroscopic and have little afterglow.