Title:
COIL DEVICE FOR MRI
Document Type and Number:
Japanese Patent JP3492009
Kind Code:
B2
Abstract:
PURPOSE: To attain both RF shield performance and the reduction of an eddy current.
CONSTITUTION: An RF shield 103 is formed in dividing structure consisting of eight pieces of copper foil 31-38, and diodes 41-48 are interposed between the copper foil, and the diodes are controlled by making active by switching the polarity of a DC bias voltage from a switch control circuit 6, and those pieces of copper foil 31-38 are connected together when a RF signal is transmitted and a NMR signal is received, and each divided part is cut off when a gradient magnetic field is changed. In this way, the RF shield performance is improved better than conventional technique to connect each copper foil with a capacitor. Also, the eddy current is reduced smaller than the conventional technique to use the copper foil without a slit or the one to connect the copper foil with the capacitor.
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Inventors:
Kazuya Hoshino
Application Number:
JP5719095A
Publication Date:
February 03, 2004
Filing Date:
March 16, 1995
Export Citation:
Assignee:
GE Yokogawa Medical System Co., Ltd.
International Classes:
G01R33/421; A61B5/055; G01R33/36; G01R33/422; (IPC1-7): A61B5/055; G01R33/422
Domestic Patent References:
JP62334A | ||||
JP4189343A | ||||
JP295347A |
Attorney, Agent or Firm:
Shinshiro Arichika
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