PULSE-HEIGHT ANALYZER AND NUCLEAR MEDICINE DIAGNOSIS DEVICE PROVIDED WITH SAME

摘要

In a pulse-height analyzer, a reference pulse generator (8) generates a reference pulse (Pm) of a predetermined peak value (Vm)for a predetermined time (Tm) when an analog radiation pulse (Pa) which is inputted to a comparator (7) is larger than an initial threshold (Vth).  A capacitor (11) and a resistance (12) increase an increase threshold (Vref) until the initial threshold (Vth) approaches the predetermined peak value (Vm) for the predetermined time (Tm) when receiving the reference pulse (Pm).  The increase threshold (Vref) is set as the reference voltage of the comparator (7).  The time from the timing at which the analog radiation pulse (Pa) exceeds the initial threshold (Vth) until the timing at which the attenuating analog radiation pulse (Pa) falls below the increase threshold (Vref) is measured, thereby measuring the pulse duration of the analog radiation pulse (Pa).  As a result, the linearity of the pulse peak value to the pulse duration is improved.