PROBLEM TO BE SOLVED: To provide an inexpensive radiation measuring device capable of measuring stably for a long period of time without generating polarization while avoiding an increase in cost caused by a process for disposing a thallium layer between an electrode and a thallium bromine crystal in a thallium bromine radiation detector and an inexpensive nuclear medicine diagnostic apparatus using the same.SOLUTION: A radiation measuring device comprises: a semiconductor radiation detector formed by using thallium bromine as a semiconductor crystal a capacitor for applying a voltage to the semiconductor radiation detector and at least one or more DC power sources capable of accumulating a positive charge and a negative charge in one electrode of the capacitor. The device has a cathode electrode and an anode electrode constituted by at least one or more metal elements selected from gold, platinum and palladium. The DC power sources supply a voltage for accumulating the positive charge and a voltage for accumulating the negative charge to the one electrode of the capacitor while periodically switching both voltages for each time less than 10 minutes.COPYRIGHT: (C)2012,JPO&INPIT【課題】臭化タリウム放射線検出器の電極と臭化タリウム結晶の間のタリウム層挿入工程によるコスト上昇を回避しつつ、ポーラリゼーション無しに長時間安定して計測できる安価な放射線計測装置、およびそれを用いた安価な核医学診断装置を提供する。【解決手段】半導体結晶として臭化タリウムを用いてなる半導体放射線検出器と、前記半導体放射線検出器に電圧を印加するコンデンサと、前記コンデンサの一方の電極に正電荷と負電荷を蓄積可能な少なくとも1つ以上の直流電源と、を備えた放射線計測装置であって、前記半導体放射線検出器のカソード電極およびアノード電極が金、白金、パラジウムのうちの少なくとも1つ以上の金属で構成され、前記直流電源が前記コンデンサの前記一方の電極に正電荷を蓄積する電圧と負電荷を蓄積する電圧を10分よりも短い時間毎に周期的に切換えて供給する。【選択図】図1
