Patent ID: 8324889

Claim:
A magnetic resonance system comprising: a basic field magnet that generates a static basic magnetic field that is substantially homogenous within an examination volume, said basic magnetic field having a basic field direction; an evaluation device; a tool adapted to be inserted into, and removed from, said examination volume; a plurality of Hall elements carried by said tool; each Hall element being configured to emit a binary signal when said basic magnetic field has a component that, relative to an element direction of the respective Hall element, that is greater than a threshold and a second level when said basic magnetic field does not have a component, relative to said element direction of the respective Hall element, that is greater than said threshold, the respective element directions of the respective Hall elements differing from each other in pairs; each Hall element being in communication with said evaluation device and transmitting the respective binary signal therefrom to the evaluation device; and said evaluation device being configured to use the respective binary signals received from the respective Hall elements, and that the respective elements direction of the respective Hall elements differ from each other in pairs, to determine an orientation of said tool relative to said basic field direction, and to initiate a response dependent on the determined orientation.