Patent US4880255A successfully refreshed from Google Patents.
Patent EP0339723A1 successfully refreshed from Google Patents.
EP0339723A1
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EP
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Magnetic resonance apparatus with uncoupled rf coils
Assignee: Koninklijke Philips NV
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Filing: 1989-04-20
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Granted: —
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Expires: 2009-04-20
Abstract
Abstract In a magnetic resonance apparatus coils of an rf coil system are incorporated for detection of magnetic resonant signals at mutually different frequencies in resonant circuits having a zero impedance for the natural frequency and an infinite impedance for a given deviating frequency. In the switching circuits a coaxial cable is used having a length which is adapted to the desired frequency.
Inventors
- 👤 Johannes Jacobus Van Vaals
- 👤 Anthonie Hendrik Bergman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 23:13
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/36; G01R33/3628; G01R33/3635
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
85 words
A magnetic resonance apparatus having a magnet system for generating a stationary magnetic field in the measuring space, a coil system for generating gradient fields in the measuring space and comprising an rf coil system for excitation and detection of magnetic resonant signals, characterized in that coils of the rf coil system to be uncoupled are incorporated in a resonant circuit having substantial zero impedance for a resonant frequency and substantial infinite impedance for a frequency deviating therefrom of a coil to be uncoupled therefrom.
Claim 2
Dependent Claim
85 words
A magnetic resonance apparatus having a magnet system for generating a stationary magnetic field in the measuring space, a coil system for generating gradient fields in the measuring space and comprising an rf coil system for excitation and detection of magnetic resonant signals, characterized in that coils of the rf coil system to be uncoupled are incorporated in a resonant circuit having substantial zero impedance for a resonant frequency and substantial infinite impedance for a frequency deviating therefrom of a coil to be uncoupled therefrom.
Claim 3
Dependent Claim
33 words
A magnetic resonance apparatus as claimed in Claim 1, characterized in that the resonant circuit comprises a coaxial cable connected parallel to the rf coil and having an adjustable impedance connected parallel thereto.
Claim 4
Dependent Claim
27 words
A magnetic resonance apparatus as claimed in Claim 2, characterized in that the coaxial cable has an open end and the parallel-arranged impedance is an adjustable inductance.
Claim 5
Dependent Claim
35 words
A magnetic resonance apparatus as claimed in Claim 2, characterized in that the coaxial cable has an open end and the parallel-arranged impedance is a parallel arrangement of a fixed inductance and a variable capacitor.
Claim 6
Dependent Claim
27 words
A magnetic resonance apparatus as claimed in Claim 2, characterized in that the coaxial cable has a short-circuited end and the parallel-arranged impedance constitutes an adjustable capacity.
References Cited (Backward Citations)
DE3634030A1
Cited
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