EP0107238A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Nuclear magnetic resonance tomography apparatus
Assignee: Koninklijke Philips NV
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Filing: 1983-10-10
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Granted: —
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Expires: 2003-10-10
Abstract
Abstract The transmitter/measurement coil (30) of a nuclear magnetic resonance tomography apparatus for medical diagnosis in which comparatively high Larmor frequencies are used, is divided into a number of parallel-connected subcoils (40). The self resonance frequency of the coil can thus be made substantially higher than the Larmor frequency, with the result that the coil (30) will have a suitably improved quality factor at higher frequencies, and measurements can be performed with an acceptable signal-to-noise ratio.
Inventors
- 👤 Rudolf Kemner
- 👤 Dirk Sinnema
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 22:47
CPC Classifications
G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/32; G01R33/36; G01R33/34; G01R33/34046; G01R33/34069; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/842; Y10S505/843; Y10S505/844
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
83 words
A nuclear magnetic resonance tomography apparatus comprising, arranged about an examination space for an object to be measured, a coil system for generating a primary magnetic field and a coil system for generating a pulsed r.f. magnetic field, and also comprising a measurement device for the detection of nuclear magnetic resonance signals generated in the object, characterized in that the self resonance frequency of the r.f. coil is substantially higher than the highest frequency component of resonance signal which is to be measured.
Claim 2
Dependent Claim
83 words
A nuclear magnetic resonance tomography apparatus comprising, arranged about an examination space for an object to be measured, a coil system for generating a primary magnetic field and a coil system for generating a pulsed r.f. magnetic field, and also comprising a measurement device for the detection of nuclear magnetic resonance signals generated in the object, characterized in that the self resonance frequency of the r.f. coil is substantially higher than the highest frequency component of resonance signal which is to be measured.
Claim 3
Dependent Claim
30 words
A nuclear magnetic resonance tomography apparatus as claimed in Claim 1, characterized in that the r.f. coil is composed of two saddle-shaped coils each sub-divided into at least two sub-coils.
Claim 4
Dependent Claim
33 words
A nuclear magnetic resonance tomography apparatus as claimed in Claim 2, characterized in that, viewed in the axial direction, each of the saddle-coil halves is sub-divided into at least two parallel coupled sub-coils.
Claim 5
Dependent Claim
48 words
A nuclear magnetic resonance tomography apparatus as claimed in Claim 3, characterized in that two sub- coils of each coil half are each time pair-wise connected to a symmetrically situated coupling point, the coupling points being pair-wise connected to symmetrically situated connection points for a power supply source.
Claim 6
Dependent Claim
35 words
A nuclear magnetic resonance tomography apparatus as claimed in Claim 1 or 2, characterized in that, viewed over the radial circumference, each of the coil halves is sub-divided into at least two parallel-connected sub- coils.
Claim 7
Dependent Claim
38 words
A nuclear magnetic resonance tomography apparatus as claimed in any one of the preceding Claims, characterized in that comb-shaped electrical screening elements are provided in the region in which axial openings between the two coil halves are situated.
Claim 8
Dependent Claim
31 words
A nuclear magnetic resonance tomography apparatus as claimed in any one of the Claims 2 to 6, characterized in that each of the sub-coils is provided with a separate read amplifier.
Claim 9
Dependent Claim
61 words
A nuclear magnetic resonance tomography apparatus as claimed in any one of the preceding Claims, characterized in that there is provided superconducting primary magnet coil which is suitable notably for measurements at Larmor frequencies beyond 15 MHz or for the measurement of magnetic resonance signals from nuclei which are present in a comparatively small concentration in the object to be measured.
Claim 10
Dependent Claim
34 words
A nuclear magnetic resonance tomography apparatus as claimed in any one of Claims 2, 3, 4, 5, 6 and 8, characterized in that the sub-coils are included in a parallel driven current control circuit.
References Cited (Backward Citations)
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