Patent ID: 6396271
Filing Date: 2002-05-28
Classification: G01R

Abstract:
A magnetic resonance apparatus having a main magnet which generates a main magnetic field through an examination region, a continuously tunable RF transmitter coil positioned about the examination region such that it excites magnetic resonance dipoles therein, an RF coil assembly which receives magnetic resonance signals from the resonating dipoles, a radio frequency transmitter which drives the tunable RF transmitter coil, a receiver connected to the RF coil assembly which receives and demodulates the magnetic resonance signals, the continuously tunable RF transmitter coil comprising:a pair of end ring conductors disposed in parallel planes, said end ring conductors interrupted by a plurality of reactive elements; a plurality of spaced leg conductors connecting said end ring conductors to form a generally cylindrical volume, said leg conductors each interrupted by at least one reactive element; and at least one tuning ring for continuously (i) inductively tuning the leg conductors, and (ii) capacitively tuning the reactive elements interrupting the leg conductors, said tuning ring comprising: a non-conductive support cylinder having an outer surface and an inner surface, and a plurality of tuning band conductors which extend axially along said non-conductive support cylinder, such that rotating the non-conductive support adjusts a degree to which the conductors overlap and capacitively couple to the leg conductors.