摘要 |
A resonator system for generating a radio frequency (RF) magnetic field in a volume under investigation of a magnetic resonance (MR) arrangement, comprises a number N of individual resonators ( 2 ) which surround the volume under investigation and which are each disposed on a flat dielectric substrate ( 1 ) around a z-axis, wherein the individual resonators ( 2 ) have windows ( 8 ) through each of which one individual RF field is generated in the volume under investigation in single operation of the individual resonators ( 2 ) and, through cooperation among the individual resonators ( 2 ), a useful RF field ( 7 ) is generated in the volume under investigation, wherein a remote RF field ( 6 ) is asymptotically generated far outside of the resonator system, and the spatial distribution of the useful RF field ( 7 ) is substantially mirror-symmetrical relative to a first plane A which contains the z-axis, and that of the asymptotic remote RF field ( 6 ) is substantially mirror-symmetrical relative to a second plane B which contains the z-axis, the useful RF field ( 7 ) extending substantially parallel to the first plane A in the volume under investigation, wherein the number of individual resonators ( 2 ) is N>4 and wherein, during operation of the resonator system at at least one point in time, the substrate plane of at least one individual resonator ( 2 ) subtends an angle of more than 40° with respect to the direction of the useful RF field ( 7 ) in the volume under investigation, and at least one further individual resonator ( 2 ) subtends an angle of less than 40° with respect to the direction of the useful RF field ( 7 ) in the volume under investigation, is characterized in that the first plane A is not rotated about the z-axis relative to the second plane B or is rotated by less than 360°/(N+1). The inventive resonator system realizes a resonator system with improved field homogeneity and full quadrature suitability, high quality factor and large efficiency using straightforward constructional measures.
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