Title:
MAGNETIC RESONANCE DIAGNOSTIC APPARATUS
Document Type and Number:
Japanese Patent JP3537951
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To prevent magnetic stimulation attributed to hourly changes in a cross magnetic field while eliminating distortion of a magnetic distribution in a photographed area by providing a coil for lowering magnetic fields to generate outside the photographed area a magnetic field for reducing a gradient magnetic field or a magnetic field to be generated together with the gradient magnetic field.
SOLUTION: A sequence controller 1 supplies a time waveform signal identical to that supplied to a gradient coil drive power source 2 to a magnetic stimulation preventing controller 4, which 4 corrects the time waveform signal supplied from the sequence controller 1 to be supplied to a magnetic stimulation preventing coil drive power source 5. The magnetic stimulation preventing coil controller 4 corrects a current amplitude of the time waveform signal supplied from the sequence controller 1 based on a voltage induced in a sensing coil 7 so that a cross magnetic field within the magnetic stimulation preventing coil 6 is canceled completely by a magnetic field for canceling cross magnetic fields generated from the magnetic stimulation preventing coil 6.
Inventors:
Kuhara, Shigehide
Application Number:
JP5476996A
Publication Date:
June 14, 2004
Filing Date:
March 12, 1996
Export Citation:
Assignee:
TOSHIBA CORP
International Classes:
G01R33/48; A61B5/055; G01R33/385; G01R33/421; (IPC1-7): A61B5/055; G01R33/421
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