Patent EP0151036A2 successfully refreshed from Google Patents.
EP0151036A2
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EP
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N.M.R. shims
Assignee: Philips Design Ltd
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Filing: 1985-01-30
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Granted: —
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Expires: 2005-01-30
Abstract
Abstract A magnetic shim (18) for an N.M.R. apparatus (1) comprises a deformable body (particularly a flexible sheet) of electrically insulating material (e.g. P.V.C.) within which magnetic material (e.g. y-ferric oxide or barium ferrite) is dispersed. The shim may easily be attached (e.g. by an adhesive backing layer) to an inside wall of the apparatus (1) and may easily be cut to size with scissors. The nature of the compensation effected by the shim may be altered by employing different magnetic materials dispersed within the non-conducting material and/or by varying their concentration.
Inventors
- 👤 Ian Robert Young
- 👤 Philip Roger Evans
- 👤 Peter Alexander Luker
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 11:29
CPC Classifications
H; H05; H05K; H05K9/00; G; G01; G01R; G01R33/00; G01R33/20; G01R33/28; G01R33/38; G01R33/387; G01R33/3873; Y; Y10; Y10T; Y10T428/00; Y10T428/28
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
27 words
A magnetic shim in N.M.R. apparatus, characterised in that said shim comprises a deformable body (18) of substantially non-electically conducting material within which magnetic material is dispersed.
Claim 2
Dependent Claim
27 words
A magnetic shim in N.M.R. apparatus, characterised in that said shim comprises a deformable body (18) of substantially non-electically conducting material within which magnetic material is dispersed.
Claim 3
Dependent Claim
15 words
A shim according to Claim 1 wherein said body (18) is deformable at room temperature.
Claim 4
Dependent Claim
22 words
A shim according to Claim 2 in the form of a flexible sheet or strip (18) and incorporating an adhesive backing layer.
Claim 5
Dependent Claim
17 words
A shim according to Claim 2 wherein said body has the consistency of putty or the like.
Claim 6
Dependent Claim
28 words
A shim according to any preceding Claim wherein said magnetic material is magnetically saturated when the shim is subjected to a magnetic field of 0.15 Tesla or greater.
Claim 7
Dependent Claim
13 words
A shim according to Claim 5, wherein said magnetic material is γ-ferric oxide.
Claim 8
Dependent Claim
34 words
A shim according to any of Claims 1 to 4 wherein said magnetic material has a substantially linear magnetisation curve when the shim is subjected to a magnetic field of 0.15 Tesla or greater.
Claim 9
Dependent Claim
13 words
A shim according to Claim 7 wherein said magnetic material is barium ferrite.
Claim 10
Dependent Claim
19 words
A shim according to any preceding Claim wherein said magnetic material is a finely divided ferromagnetic metal or alloy.
Claim 11
Dependent Claim
21 words
A shim according to Claim 1 wherein said body is composed of thermoplastic material which can be deformed on moderate heating.
Claim 12
Dependent Claim
23 words
A shim as claimed in any of Claims 3 to 10 whose minimum dimension perpendicular to its thickness is at least 100 mm.
Claim 13
Dependent Claim
43 words
A flexible sheet or strip of substantially non-electrically conducting material (18) within which magnetic material is dispersed, said sheet or strip incorporating an adhesive backing layer and being capable of being cut by hand to form a shim as claimed in Claim 3.
Claim 14
Dependent Claim
23 words
N.M.R. apparatus incorporating a magnetic shim (18) as claimed in Claim 3 attached to an inner surface of its main field winding (1).
Claim 15
Dependent Claim
11 words
N.M.R. imaging apparatus as claimed in Claim 12 or Claim 13.
Claim 16
Independent Claim
40 words
A method of reducing magnetic field inhomogeneities in N.M.R. apparatus, involving the steps of cutting to size a deformable substantially non-electrically conducting body incorporating dispersed magnetic material and applying said body (18) to a supporting surface of the N.M.R. apparatus.
Claim 17
Independent Claim
40 words
A method of reducing magnetic field inhomogeneities in N.M.R. apparatus, involving the steps of cutting to size a deformable substantially non-electrically conducting body incorporating dispersed magnetic material and applying said body (18) to a supporting surface of the N.M.R. apparatus.
Claim 18
Dependent Claim
24 words
A method according to Claim 15 wherein one or both of said steps are repeated until satisfactory compensation is achieved by trial and error.
Claim 19
Dependent Claim
23 words
A method according to Claim 15 or Claim 16 wherein said body (18) is in the form of a flexible sheet or strip.
References Cited (Backward Citations)
No citation records indexed.
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