| 摘要 |
A gradient coil system has a cylindrical section in a central region, which contains no conductor elements and has a maximum outer radius that is larger than a minimum inner radius of conductor elements of a main gradient coil. An outer radius of this cylindrical section is only insubstantially smaller or equal in size to a minimum inner radius of a shielding coil in this axial range. The free space in the center of the gradient coil system is used to insert a passive RF shield, whose radius in a central region becomes larger over a certain length than its radius in outer regions. The RF shield is constructed from at least three partial sections, which are electrically interconnected. The actively shielded gradient coil system maximizes the volume of the RF region without loss of gradient coil system performance. |
