Abstract: Preprocessing is conducted on a unipolar pulse output from a photomultiplier tube, to thereby generate a bipolar signal (bipolar pulse). In the bipolar signal, the falling waveform portion (back slope) of the initial peak waveform is steep, and also cuts across the baseline, whereby it is possible to accurately identify the falling point as the zero crossing point. The accuracy of identification of the pulse width “t” can be improved thereby. In addition to the pulse width, further reference may be made to the crest value of the unipolar pulse, the crest value of the bipolar signal, and the like, when determining line type.

Abstract: A survey meter according to the present invention is a portable radiation measurement device. The survey meter comprises a tip portion, an intermediate portion, and a grip portion. A display unit is provided on the top surface of the intermediate portion. The tip portion extends to the intermediate portion with a bent portion therebetween. The tip portion forms an inclined portion. The grip portion has a constricted portion. A radiation detection unit is provided inside the tip portion and is formed by a plurality of sensors arranged in the right-left direction.

Abstract: Preprocessing is conducted on a unipolar pulse output from a photomultiplier tube, to thereby generate a bipolar signal (bipolar pulse). In the bipolar signal, the falling waveform portion (back slope) of the initial peak waveform is steep, and also cuts across the baseline, whereby it is possible to accurately identify the falling point as the zero crossing point. The accuracy of identification of the pulse width “t” can be improved thereby. In addition to the pulse width, further reference may be made to the crest value of the unipolar pulse, the crest value of the bipolar signal, and the like, when determining line type.

Abstract: A survey meter according to the present invention is a portable radiation measurement device. The survey meter comprises a tip portion, an intermediate portion, and a grip portion. A display unit is provided on the top surface of the intermediate portion. The tip portion extends to the intermediate portion with a bent portion therebetween. The tip portion forms an inclined portion. The grip portion has a constricted portion. A radiation detection unit is provided inside the tip portion and is formed by a plurality of sensors arranged in the right-left direction.