RADIATION DETECTION DEVICE

PROBLEM TO BE SOLVED: To perform abnormality diagnosis based on a count value distribution of a noise signal. SOLUTION: When performing abnormality diagnosis, a radiation detector 22 is in the state where a radiation is not inputted, and only the noise signal is outputted from a preamplifier 24. The noise signal is used as an observation voltage Vobs, and inputted into each observation voltage input terminal of two comparators 28, 30 via a branch circuit 26. In the comparators 28, 30, the observation voltage comprising the noise signal 46 is compared with a scan reference voltage 48 changing stepwise, to thereby acquire a count value distribution curve (observation curve) of the noise signal. Offset correction is performed respectively relative to observation curves acquired by the two comparators, and the curves are viewed by an operator, to thereby enable abnormality diagnosis. Otherwise, existence of an abnormality can be determined by comparing each observation curve with a reference curve having no abnormality. COPYRIGHT: (C)2007,JPO&INPIT