| 摘要 |
The invention provides for a magnetic gradient coil (110) for a magnetic resonance imaging system (100, 200). The magnetic gradient coil is actively shielded, wherein the magnetic gradient coil is operable for generating a magnetic field (504). The magnetic field has a cylindrical axis of symmetry (130). The gradient coil has a length (132) parallel with the cylindrical axis of symmetry. The magnetic gradient coil has an outer surface (134). The magnetic field comprises an external magnetic field outside of the outer surface. The external magnetic field has at least four reduced field regions (136, 138, 140, 142) along the length where the modulus of the magnetic field is less than the average of the modulus of the magnetic field along the length. |
