Patent ID: 8902030

Claim:
Device for generating an orientable and locally uniform magnetic field, comprising N≧3 identical assemblies (EB n ) of cylindrical coils, each of said assemblies comprising at least a first (B n 1 ) and a second (B n 2 ) coil, said coils being coaxial with an axis oriented along a direction z and being arranged symmetrically on either side of a plane xy perpendicular to said z-axis, with a gap in the axial direction, said assemblies being arranged such that their outlines in said xy-plane are regularly spaced along a circle of centre O and of radius a 0 >0, so as to leave a central free space (ELC), the device also comprising a supply system (SA) configured to supply each of said coils with a current I n i , n being an index representing the coil assembly and i being equal to 1 for said first coils and to 2 for said second coils, expressed by the sum of a first term I z having a given value for all the coils, and a second term I xy equal to (−1) i-1 ·I 0 ·sin θ 0 ·cos(φ n −φ 0 ), where I 0 is a nominal current, φ n is the azimuthal angle, relative to a reference direction in the xy-plane, of the nth coil assembly, φ 0 is the azimuthal angle, relative to the same reference direction, of a magnetic field to be generated in the centre of said circle by said coils, and θ 0 is the zenith angle of the same magnetic field relative to the z-axis, at least the angle φ 0 being adjustable by a user.