Patent ID: 9268028
Filing Date: 2016-02-23
CPC Classification: G01R,G01T,G06F

Claim Text:
1. A radiation measuring apparatus comprising: a radiation detector; a pulse amplifier which amplifies a detector signal from the radiation detector; a waveform analyzing section which analyzes a waveform of a detector signal pulse from the pulse amplifier, distinguishes a regular waveform and a noise waveform, and outputs the regular waveform and the noise waveform as a first digital pulse and a second digital pulse, respectively; a first counter which counts the first digital pulse; a second counter which counts the second digital pulse; an up-down counter in which the first digital pulse is inputted to an addition input and a feedback pulse is inputted to a subtraction input, and which outputs an addition-subtraction accumulated value obtained by accumulating the differences therebetween; a negative feedback pulse generation circuit which generates the feedback pulse based on the addition-subtraction accumulated value; an accumulation control circuit which specifies weighting of counting for the up-down counter; an accumulated value setting circuit which forcibly sets the addition-subtraction accumulated value of the up-down counter; and a calculation section which calculates a count rate from the addition-subtraction accumulated value of the up-down counter, and detects noise intrusion, based on count values from the first counter and the second counter, wherein the calculation section stores the addition-subtraction accumulated value for the previous calculation cycle, and the calculation section, when noise intrusion has been detected, performs predetermined calculation using the addition-subtraction accumulated value for the previous calculation cycle instead of the value for the present calculation cycle, to output the calculation result, and causes the accumulated value setting circuit to set the addition-subtraction accumulated value of the up-down counter at the value for a calculation cycle just before the noise intrusion.