PROBLEM TO BE SOLVED: To provide a technique for securing a comfortable examination space in a tunnel type MRI apparatus without increasing the manufacturing cost of the MRI apparatus and sacrificing performance thereof.SOLUTION: In an RF coil provided with a hollow-shaped outer conductive element and ribbon-shaped conductive elements disposed along the outer conductive element in the axial direction, the ribbon-shaped conductive elements are disposed with uneven intervals to secure an internal space at a position where the ribbon-shaped conductive elements are not disposed. Wherein, in order to obtain uniform sensitivity at the center section of the RF coil, the ribbon-shaped conductive elements and the outer conductive element are electrically connected via capacitors of which capacitances are adjusted so that a magnetic field component perpendicular to the center axis is to be generated at a desired resonance frequency, and the ribbon-shaped conductive elements are axis-symmetrically disposed with respect to the center axis of the outer conductive element.COPYRIGHT: (C)2011,JPO&INPIT【課題】トンネル型MRI装置において、MRI装置の製造コストを増大させることなく、また、性能を犠牲にすることなく、快適な検査空間を確保する技術を提供する。【解決手段】中空形状の外部導体と、外部導体に沿って軸方向に配置されるリボン状導体とを備えるRFコイルにおいて、リボン状導体を不当間隔に配置し、リボン状導体の無い部分の内部空間を確保する。ただし、RFコイルの中心部分で均一な感度を得るため、リボン状導体と外部導体との間は、所望の共振周波数で中心軸に垂直な磁場成分を発生するよう容量が調整されたキャパシタを介して電気的に接続するとともに、リボン状導体を外部導体の中心軸に対して軸対称に配置する。【選択図】 図5
