| 摘要 |
The apparatus comprises a mainly cylindrical RF coil (9) which has a central axis (35) extending in its longitudinal direction and comprises a number of axial conductor elements (37) which extend parallel to the central axis across a mainly cylindrical surface, and also comprises end conductor elements which extend around the central axis near the ends of the axial conductor elements. The axial conductor elements (37) are distributed across the circumference of the cylinder in such a manner that they occupy predetermined positions relative to a zero position (39). The RF coil (9) is arranged to generated a substantially sinusoidal current distribution as a function of the position of the axial conductor elements (37) on the circumference of the cylinder, expressed as the angle ( alpha ) of this position relative to the zero position (39), in order to enable a substantially uniforme RF magnetic field, oriented perpendicularly to the cylinder axis (35), to be generated and/or received. Each end conductor element consists of a number of loop conductor segments (43), each of which interconnects the corresponding ends of two axial conductor elements (37). At least some of the axial conductor elements (37) constitute, together with the loop conductor segments (43) connected to their ends, a coil element (44) which is composed of a number of turns of an elongate electric conductor (45), all coil elements thus formed being electrically connected in series.
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