The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 15, 1994
Filed:
Feb. 10, 1993
Mutsumi Yoshikata, Noda, JP;
Tsuneo Maeda, Tokyo, JP;
Hitachi Medical Corporation, Tokyo, JP;
Abstract
In a magnetic resonance imaging apparatus, picture quality of a tomographic image is prevented from deteriorating by reducing the influence due to a change in environmental magnetic field around magnetic field generating means. A phase correcting circuit for correcting the phase of a correcting current supplied to correcting magnetic field coils is provided in a correction control circuit which amplifies a detection signal representative of the change in the environmental magnetic field from a magnetic field sensor. This enables to correct the phase of a correcting magnetic field generated from the correcting magnetic field coils. The difference between the phase of the change in the environmental magnetic field and the correcting magnetic field generated by the correcting magnetic field coils can be reduced.