Superconductive magnet for magnetic resonance imaging has pole piece which extends radially at distance at least 75 per cent that of main coil

摘要

The magnet has a first component (14) comprising a superconducting main coil that is arranged coaxially, at a first radial spacing from the longitudinal axis of the magnet and carries a first main current in a first direction. A magnetic pole piece is aligned coaxially to the axis and is spaced apart form the main coil of the first component. Most of the pole piece of the first component is arrange radially inwards w.r.t. the main coil. The pole piece extends radially outwards from the axis to give a spacing which is at least 75 per cent of the first radial spacing. During operation of the magnet, the pole piece has a temperature which is equal to that of the main coil of the first component. Independent claims are included for a super conductive, open magnet, and two methods of creating compactness and a homogenous magnetic resonance imaging space for a superconductive magnet.