| 摘要 |
PROBLEM TO BE SOLVED: To provide a radiation detector capable of always obtaining a stable high sensitivity, low afterglow and low noise characteristics irrespective of the ambient temperature by using the detector using fluorescence elements each having at least Gd, Al, Ga and O in a suitable temperature range with Ce as a light emitting element, and an X-ray CT system capable of obtaining a tomographic image of high resolution not having an artifact by using the radiation detector. SOLUTION: A luminescence by the fluorescence elements (1) each having a matrix crystal made of a garnet structure containing at least Gd, Al, Ga and O with Ce as a light emitting element is transduced into an electric signal by photoelectric transducers (2) each of a silicon photodiode by using the element (1), the transducers (2) are arranged in an array-like state on an array board and contained together with the elements (1) in a detector case (3). A temperature sensor (6) and a temperature control means (5) are provided in the case, and the temperature T of the element (1) and the element (2) is controlled to 0 deg.C<=T<=50 deg.C by a temperature control circuit (7). This temperature controlled radiation detector is used as the X-ray detector of the X-ray CT system to obtain the tomographic image of high resolution not having artifact.
|
