Peter T. While1, Larry K. Forbes1,
Stuart Crozier2
1School of Maths and Physics,
University of Tasmania, Hobart, TAS, Australia; 2School of
Information Technology and Electrical Engineering, University of Queensland,
Brisbane, QLD, Australia
An
analytic method is described for the theoretical design of 3D gradient coils
for open MRI systems. Rather than restricting coil windings to planar
surfaces, the precise 3D geometry is obtained as part of the optimisation.
The inverse problem is solved using regularisation with a minimum power
constraint. A priority streamline seeding technique is used to position the
windings. Results for an unshielded coil display concentrated current near
the DSV with looped return path windings. However, for a shielded coil the
windings are confined to biplanar surfaces, suggesting this is the optimum
geometry for a shielded minimum power open coil.