Pulse height analyzer and nuclear medicine diagnosis apparatus provided with the same

摘要

With a pulse-height analyzer, a reference-pulse generator generates a reference pulse of a given pulse height for a given period of time when an analog radiation pulse inputted to a comparator is higher than an initial threshold. A capacitor and a resistor receive the reference pulse, and then increase an increment threshold for the given period of time from the initial threshold to the given pulse height. Then the increment threshold is set as a reference voltage of the comparator. A pulse time width of the analog radiation pulse is determined through measuring a period of time from timing where the analog radiation pulse exceeds the initial threshold to timing where the analog radiation pulse being attenuated falls below the increment threshold.

主权项

1. A pulse height analyzer for determining a pulse height of a radiation pulse, obtained by converting emission due to incidence of radiation, through measuring a period of time from timing where the radiation pulse exceeds a given threshold to timing where the radiation pulse is attenuated to fall below the given threshold, and analyzing the pulse height of the radiation pulse to take out only a radiation pulse of a necessary pulse height, comprising:
a threshold increasing device increasing the given threshold in synchronization with the timing where the radiation pulse exceeds the given threshold and measuring a period of time until the radiation pulse falls below the increment given threshold.