Schematic diagram of imaging magnet

A large hollow cylinder contains windings of superconducting wire bathed in cryogen (coolant). Additional shim windings provide small magnetic field corrections. 3 sets of nonsuperconducting gradient coils provide spatial localization of spins. An RF transmit/receive coil provides the RF excitation for each MR sequence and collects the signals used to create an image. Control electronics are located outside the room containing the magnet. The part of the patient being imaged is moved to the center of the magnet by the transport table.