Method and system for adjusting the fundamental symmetric mode of coupled high temperature superconductor coils

• US 7,521,932 B2
• Filed: 04/29/2004
• Issued: 04/21/2009
• Est. Priority Date: 05/06/2003
• Status: Expired due to Fees

• Current Assignee: Penn State Research Foundation (Pennsylvania State University)
• Original Assignee: Penn State Research Foundation (Pennsylvania State University)
• Inventors: Carter, Charles F. III, Sheng, Jiunn, McCambridge, James D., Wilker, Charles, Laubacher, Daniel B.
• Primary Examiner(s): Shrivastav; Brij B
• Application Number:
  US10/835,345
• Publication Number:
  US 20050046420A1
• Time in Patent Office: 1,818 Days
• Field of Search: 324300-322, 310/328, 310/323, 438 29- 32, 347/107, 400/120
• US Class Current: 324/318
• CPC Class Codes: G01N 24/084 Detection of potentially hazardous samples, e.g. toxic samples, explosives, drugs, firearms, weapons
• CPC Class Codes: G01R 33/34007 Manufacture of RF coils, e.g. using printed circuit board technology; additional hardware for providing mechanical support to the RF coil assembly or to part thereof, e.g. a support for moving the coil assembly relative to the remainder of the MR system
• CPC Class Codes: G01R 33/34023 Superconducting RF coils
• CPC Class Codes: G01R 33/34053 Solenoid coils; Toroidal coils
• CPC Class Codes: G01R 33/341 comprising surface coils
• CPC Class Codes: G01R 33/3642 Mutual coupling or decoupling of multiple coils, e.g. decoupling of a receive coil from a transmission coil, or intentional coupling of RF coils, e.g. for RF magnetic field amplification
• CPC Class Codes: G01R 33/441 Nuclear Quadrupole Resonance [NQR] Spectroscopy and Imaging
• CPC Class Codes: H01F 21/04 by relative movement of turns or parts of windings
• CPC Class Codes: H01F 41/045 Trimming
• CPC Class Codes: H01F 5/003 Printed circuit coils
• CPC Class Codes: H01F 6/06 Coils, e.g. winding, insulating, terminating or casing arrangements therefor

Abstract

The frequency of the fundamental symmetric mode of two or more coupled essentially identical high temperature superconductor coils can be tuned, with little degradation in Q, by mechanically displacing the two or more coils with respect to one another. These coupled coils are useful in a detection system for detecting frequencies.

Claims

1. A frequency detection system comprising:

two essentially identical coupled planar high temperature superconductor self-resonant coils, said coils being able to detect signals having a predetermined fundamental symmetric mode resonance frequency, wherein said two coils are parallel; and

means for tuning the resonance frequency of said coupled coils to said fundamental symmetric mode frequency by varying one or more distances between said coils,

wherein said means comprises micropositioners to vary the distance between the planes of said two coils from essentially zero to about 50% of the radius of the coils.

2. The frequency detection system of claim 1, wherein said frequency detection system is a nuclear quadrupole resonance detection system.

3. A frequency detection system comprising:

two essentially identical coupled planar high temperature superconductor self-resonant coils, said coils being able to detect signals having a predetermined fundamental symmetric mode resonance frequency, wherein said two coils are parallel; and

means for tuning the resonance frequency of said coupled coils to said fundamental symmetric mode frequency by varying one or more distances between said coils,

wherein said means comprises micropositioners to vary the off-axis displacement of one of said two coils with respect to the other coil,

wherein the planes of the two coils are separated by a distance of from essentially zero to about 50% of the radius of said coils.

4. The frequency detection system of claim 3, wherein said frequency detection system is a nuclear quadrupole resonance detection system.

5. A frequency detection system comprising:

two essentially identical coupled planar high temperature superconductor self-resonant coils, said coils being able to detect signals having a predetermined fundamental symmetric mode resonance frequency, wherein said two coils are parallel; and

means for tuning the resonance frequency of said coupled coils to said fundamental symmetric mode frequency by varying one or more distances between said coils,

said means comprises micropositioners to vary said distance between said planes of said two coils from essentially zero to about 50% of the radius of said coils and to vary the off-axis displacement of one of said two coils with respect to the other coil from essentially zero to about the radius of said two coils.

6. The frequency detection system of claim 5, wherein said frequency detection system is a nuclear quadrupole resonance detection system.

7. A frequency detection system comprising:

three or four essentially identical coupled planar high temperature superconductor self-resonant coils, said coils being able to detect signals having a predetermined fundamental symmetric mode resonance frequency, wherein said three or four coils are parallel; and

means for tuning the resonance frequency of said coupled coils to said fundamental symmetric mode frequency by varying one or more distances among said coils,

said means comprises micropositioners to vary the off-axis displacements of all of said three or four coils with respect to the other coils.

8. The frequency detection system of claim 7, wherein said frequency detection system is a nuclear quadrupole resonance detection system.

9. A frequency detection system comprising:

three or four essentially identical coupled planar high temperature superconductor self-resonant coils, said coils being able to detect signals having a predetermined fundamental symmetric mode resonance frequency, wherein said three or four coils are parallel; and

means for tuning the resonance frequency of said coupled coils to said fundamental symmetric mode frequency by varying one or more distances between said coils,

wherein said means comprises micropositioners to vary the distance between the planes of said three or four coils and to vary the off-axis displacements of all of said three or four coils with respect to the other coils.

10. The frequency detection system of claim 9, wherein said frequency detection system is a nuclear quadrupole resonance detection system.