US Patent 7351194 Arrangement for influencing magnetic particles

An arrangement for influencing magnetic particles in a region of action with the help of an arrangement for generating magnetic fields, by which there is generated a spatially inhomogeneous magnetic field having at least one zone in which the magnetization of the particles is in a state of non-saturation, whereas it is in a state of saturation in the remaining zone. By moving the zone within the region of action, a change in magnetization is produced that can be detected from outside in a first mode of operation and gives information on the spatial distribution of the magnetic particles in the region of action. In a second mode of operation, the movement is repeated so frequently that the region of action heats up.