RF SURFACE RESONATOR FOR A MAGNETIC RESONANCE IMAGING APPARATUS

摘要

The invention relates to a flat quadrature RF surface resonator for a vertical field MRI magnet. Various steps are proposed so as to achieve a desired variation of the field strength. These steps concern the selection of the number, the shape and the length of radially extending conductor structures (30x, 31x, 32x, 33x; 40x, 41x, 42x, 43x) as well as of conductor loops (310 to 390; 410 to 490) for the return current, the shape of RF shields (12, 13) and the insertion of capacitive elements (Cix, Cax) between the conductor structures and the conductor loops on the one side and a reference potential on the other side, and also capacitive elements (Clx) in the conductor structures and/or conductor loops. Finally, a desirable variation of the field strength can also be achieved by the separation of parts of the surface resonator by means of switchable diodes (Dx).