Magnetic field generation system

Magnetic field generation system (200;

• 300;
• 400) comprising a magnetic circuit comprising:
• a central pole (220;
• 320;
• 412E) arranged above a plane (XY), the axis of said central pole extending along an orthogonal direction (Z) substantially corresponding to the direction orthogonal to the plane;
• at least two planar poles (216A, 216B, 216C, 216D;
• 316A, 316B, 316C) arranged symmetrically on the plane with respect to the axis of the central pole, each planar pole being supported by a portion of the magnetic circuit;
• and
• at least two coils (230A, 230B, 230C, 230D;
• 330A, 330B, 330C), including at least one coil associated with each planar pole, each coil associated with a planar pole surrounding the magnetic circuit portion supporting said planar pole;
• two coils associated with two different planar poles being adapted to being connected to two distinct power supply circuits;
• each power supply circuit being adapted to circulating through at least one coil to which it is connected a current having an intensity and a direction determined according to a desired magnetic field and to the orientation in the plane of the planar pole associated with said coil.