Non-orthogonal Shim coil system for the correction of magnetic-field inhomogeneities in nuclear magnetic resonance apparatuses

摘要

Such a system is used, for example, in spectroscopic or imaging nuclear magnetic resonance. Individual non-overlapping and separately controllable shim coils (1 to 8) generate correction fields which can be allocated linearly independent but not necessarily orthogonal spectral vectors. Every spectral vector which is required for correcting the inhomogeneities can thus be unambiguously generated by suitably activating the individual coils (1 to 8). The shim coil system according to the invention is more economic both with respect to the material expenditure and with respect to the energy necessary for its operation. IMAGE