Patent ID: 7141970

Claim:
A magnetic resonance imaging apparatus comprising a phantom disposed in static magnetic field; an eddy current measurement means which takes an image of the phantom by repeatedly executing an eddy current measurement sequence composed of an application of a test gradient magnetic field having an application time longer than a time constant of an eddy current as a measurement object and having a predetermined intensity in a predetermined axial direction and of a repetition in a plurality of times of a pulse sequence which is started in response to rising up and falling down of the test gradient magnetic field while changing phase encoding amount thereof, and successively measures a plurality of image data containing magnetic field variation information due to eddy current induced by rising up and falling down of the test gradient magnetic field in a unit of the repetition time of the pulse sequence; and compensation current calculating means which determines from the image data obtained in the repetition time of a current value to be flown into a magnetic field variation compensating coil at a dine when taking an image of a subject and for compensating the eddy current.