COMPENSATION SYSTEM OF GRADIENT MAGNETIC FIELD AND POLARIZED MAGNETIC FIELD

PURPOSE: To reduce sprious distortion by measuring a sprious effect to be exerted upon both a gradient magnetic field, in which a gradient magnetic field pulse depends on time, and an equal magnetic field to be changed with the passage of time. CONSTITUTION: A host computer system 100 executes control to an MR system through a system controller 118 and a gradient amplifier system 128. Besides, the host computer system 100 prepares the indication of sprious magnetic fields at respective positions by analyzing provided NMR signals and estimates the impulse responses of both the gradient magnetic field and the equal magnetic field to the excitation of the gradient coil, and an exact compensation circuit is formed for a gradient magnetic field power source and a power source for driving a coil for preparing the equal magnetic field while using these impulse responses.