PURPOSE: To eliminate uneven density by adding newly to apply an inclined magnetic field by an equal quantity each between specific pulses or between the specific pulse and read-out of a signal, and varying one of the magnitude or the direction of the newly added inclined magnetic field between adjacent slices.
CONSTITUTION: A high frequency magnetic field 101 generates two kinds of 90° and 180° pulses from a high frequency magnetic field generating device 204. An inclined magnetic field generating device 203 generates a slice direction inclined magnetic field 102, an encoding direction inclined magnetic field, 103, and a read-out direction inclined magnetic field 104, controls the strength of three kinds of magnetic field and superposes them, and generates the inclined magnetic fields in the slice direction, the encoding direction and the read-out direction having an arbitrary cross section. In the case of two slices, an additional part 106 in the slice direction, an additional part 107 in the encoding direction and an additional part 108 in the read-out direction are added to a second slice. Also, in the case the number of slices is ≥2, the inclined magnetic field is added newly by an equal quantity each between the 90° pulse and the 180° pulse and between the 180° pulse and read-out of a signal to the sequence of each slice. In such a way, uneven density of an image can be erased.
SANO KOICHI
YOKOYAMA TETSUO
KAJIYAMA KOJI
HITACHI MEDICAL CORP
Next Patent: MRI DEVICE PROVIDED WITH PROCESS FOR CORRECTING PRIMARY MAGNETOSTATIC FIELD UNUNIFORMITY AND EXECUTI...