Design of finite size uniplanar gradient coil for fully open MRI system with horizontal magnetic field

A new approach to the design of uniplanar gradient coils for fully open magnetic resonance imaging (MRI) system with horizontal directed field is proposed to build a specified gradient magnetic field in a target region. In this new methodology, the surface current density of the coil is represented by a two-dimensional Fourier series expansion. A cost function is constructed in terms of the summation of a set of pointspsila squared error in target field, the stored magnetic energy and dissipated power. Minimizing the cost function, the continuous current density distribution for the uniplanar gradient coil is obtained. Applying the stream function technique to the resulting continuous current distribution, discrete current patterns can be generated. Employing the Biot-Savart law to the discrete current loops, the gradient magnetic field has been re-evaluated in order to validate the method proposed. Using this approach, a uniplanar x-gradient coil with high level of linearity is designed.