Patent ID: 7069195
Filing Date: 2006-06-27
Classification: G01R

Abstract:
1. A method of designing a magnetic field gradient coil assembly using wound inner and outer coils, said method comprising the steps of: setting or resetting the number of said inner coils and optimizing their positions such that a resulting magnetic field strength falls within a tolerable range of a target magnetic field gradient under shielded conditions; setting or resetting the number of said outer coils and the number of turns of each outer coil; calculating Fourier components of an electric current spatial distribution necessary for the outer coils; optimizing positions of the outer coils to approximate the Fourier components of the current distribution; calculating magnetic fields leaking from the inner and outer coils, respectively; calculating magnetic field distortions caused by eddy currents at the outside of said outer coil produced by the leaking magnetic fields; and resetting the number of the outer coils and the number of turns of each outer coil such that the magnetic field distortions caused by eddy currents fall within a tolerable range.