PURPOSE: To separate the images of two object materials by executing a spin echo sequence, collecting first data, simultaneously, shifting the timing of a 180° pulse so as to make the position difference in spin between two object materials into 180° and collecting second data.

CONSTITUTION: The first data are collected by executing the spin echo sequence, and simultaneously, the second data are collected by executing the spin echo sequence in shifting the timing of the 180° pulse so as to make the phase difference in the spin between two object materials into 180°. The phase obtained in executing a correction after one side of -180° to 0° and 0° to 180° of the phase of the latter data is inverted by 180°, subtracted from the phase of the second data, and the sum and difference between the data and the first data are obtained. Thus, the images of two object materials, in which an influence due to a static magnetic field is removed, can be obtained.