PROBLEM TO BE SOLVED: To provide a position detection system capable of detecting the position of a surgical instrument inserted in the body of a patient even under a strong magnetic field.SOLUTION: A position detection system includes a transmission antenna at least three receiving antennas and a signal processing unit for obtaining position coordinates of the transmission antenna from received electric waves. The transmission antenna has radiation elements 23a and 23b forming a dipole antenna a ferroelectric body 24 having a hole 26 formed through an approximately center portion thereof, and covering the radiation elements 23a and 23b with the hole 26 and coated metal 25a and 25b disposed on a surface of the ferroelectric body 24. Through a cable 2 connected to a high-frequency oscillator, high frequency waves are fed to the radiation elements 23a and 23b. The radiation elements 23a and 23b are helical-shaped or meander-shaped dipole antennas. The radiation element 23a and the coated metal 25a are electrically connected with each other, and the radiation element 23b and the coated metal 25b are electrically connected with each other. The coated metal 25a and 25b are disposed opposite one another so as to form a capacitor.COPYRIGHT: (C)2014,JPO&INPIT【課題】強磁場下においても患者の体内に挿入された手術器の位置検出が可能な可搬型の位置検出システムを提供する。【解決手段】送信アンテナと、少なくとも3本の受信アンテナと、受信した電波から送信アンテナの位置座標を求める信号処理部とを備え、送信アンテナが、ダイポールアンテナを構成する放射素子23a,23bと、略中心部を貫く孔26を有し、孔26により放射素子23a,23bを覆う強誘電体本体24と、強誘電体本体24の表面に配置された被覆金属25a,25bと、を備え、高周波発振器に接続されたケーブル2を介して、放射素子23a,23bに高周波が給電され、放射素子23a,23bが、ヘリカル形状またはメアンダ形状のダイポールアンテナである。放射素子23aと被覆金属25aとが電気的に接続され、放射素子23bと被覆金属25bとが電気的に接続され、被覆金属25a,25bが対向して配置されてキャパシタを構成する。【選択図】図12
