| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a radiation monitor which is capable of performing temperature compensation of a radiation detector inexpensively and effectively. <P>SOLUTION: A radiation monitor comprises a radiation detector 1 which detects radiation of a measurement target and converts the radiation into a current pulse, a preamplifier 2 which converts the current pulse of the radiation detector into a voltage pulse, a main amplifier 3 which amplifies the voltage pulse of the preamplifier, and a rate meter 5 which measures the radiation from the voltage pulse outputted from the main amplifier. The preamplifier includes an operational amplifier 21 which inputs the current pulse of the radiation detector to a polarity inverted input terminal, a negative feedback capacitor 22 and a negative feedback resistor circuit 23 which are connected between the polarity inverted input terminal of the operational amplifier and its output terminal. In the negative feedback resistor circuit, two resistors 231, 232 are connected in series and one resistor 233 is connected between that connecting point and a ground or common so as to provide a T-shaped configuration. At least one of resistors connected in series performs temperature compensation of the radiation detector as a resistor having positive temperature characteristics. <P>COPYRIGHT: (C)2013,JPO&INPIT |
