JP2926427B

PURPOSE:To cut production cost by obviating the need of the adjusting function for the revolution direction by obtaining an image free from the influence of the eddy current magnetic field by electrically compensating the eddy current magnetic field generated by the angular deflection between an inside coil and an outside coil. CONSTITUTION:A scan control signal Gx is differential-calculated in a differential calculation circuit 11, and added with a gradient signal Gx, and the result is applied into an X coil 25, and the eddy current magnetic field which is generated on the basis of the gradient signal Gx in the case where the gradient signal Gx is applied to the X axis because of the Gx and the dimension errors of an inside coil 1 and an outside coil 2. A differentiation circuit 12 differential-calculates the gradient signal Gy, and corrects the eddy current induced by the Gyx which is generated on the inside coil 1 of the X coil 25 by the gradient signal Gy. In a differential circuit 13, similarly to the case of the differential circuit 11, and further, in the differential circuit 14, similarly to the case of the differential circuit 12, the eddy current in the Y-axial direction which is caused by the gradient signal Gy is corrected. A differential circuit 15 operates similarly to the differential circuits 11 and 13, and the eddy current in the Z-axial direction which is caused by the gradient signal Gz is corrected.