| 摘要 |
<p>PURPOSE:To enhance the sampling density of gamma pairs and to make it possible to expand the detecting range without increasing the number of detectors by individually moving a plurality of arrays which comprise a plurality of the detectors that are arranged in a cylindrical pattern in the axial direction. CONSTITUTION:A detector measures a pair of radiations radiated from an object by the dosage of nuclide which discharges positron at the same time in the exact opposite directions. The detector is constituted by arranging radiation detectors 1 in the cylindrical pattern having the specified axial center. The detector 1 is formed of a scintillator 11 and a PMT(photomultiplier) 12. The detectors 1 are alinged in the direction of the Z axis in a detector array 4. The detector array 4 is attached to a plurality of guide rails 13 which are provided in parallel with the Z axis to that the array 4 can be individually moved in the axial direction. Since the array 4 can be individually moved in the axial direction, the sampling density of gamma pairs can be enhanced and detecting range can be broadened without increasing the number of the detectors 1. Therefore, the low cost can be achieved because it is not necessary to increase the expensive detectors 1.</p> |
