R.F. coil system for generating and/or receiving alternating magnetic fields

摘要

An R.F. coil system is described for generating and/or receiving at least substantially homogeneous alternating magnetic fields, notably in nuclear magnetic resonance apparatus. The system is arranged about an essentially cylindrical examination space and comprises at least four conductor segments which are oriented essentially parallel to the longitudinal central axis of the examination space. The conductor segments are arranged about the circumference of the examination space symmetrically with respect to at least one plane which extends through the longitudinal central axis and are interconnected so as to form a closed loop. The conductor segments which receive a current of the same sense with respect to the longitudinal axis, are interconnected at neighboring ends by conductor elements which are oriented essentially in the circumferential direction of the examination space so as to form conductor groups. The conductor groups are, in turn, interconnected by connection leads which are connected to the conductor elements. The length (LO) of the connection leads are chosen so that an amplitude maximum of the R.F. currents is formed at the center of each conductor segment while at least one amplitude minimum of the R.F. currents is present on each connection lead.