Inductive coupling in multiple resonance circuits in a nuclear magnetic resonance probe and methods of use

Patent metadata

Field	Value
Publication number	US-10620282-B2
Application number	US-201816054887-A
Country	US
Kind code	B2
Filing date	Aug 3, 2018
Priority date	Mar 14, 2016
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

In various embodiments of the invention, inductive coupling can be to a secondary coil rather than a primary coil in order to optimize the topology of the NMR probe. In addition, by coupling to a secondary coil using a detection coil located below the lower insulator the RF homogeneity and signal to noise can be improved together with the NMR probe topology. By effecting inductive coupling to an inductor in a multiple resonance circuit, rather than to the sample inductor parameters associated with the NMR, probe construction can be arranged to increase RF homogeneity and signal to noise, while reducing space utilization constraints. In various embodiments of the invention, the primary mode in a secondary coil can be split into two modes with a resonator with inductive coupling to the secondary coil.

First claim

What is claimed is:

1. A Nuclear Magnetic Resonance (NMR) probe comprising:
a primary circuit including a primary inductor coil located in a first region above a lower insulator with a primary resonance mode;
one or more secondary circuits including one or more secondary inductor coils located in a second region below the lower insulator, where the one or more secondary inductor coils are electrically connected to the primary inductor coil; and
one or more inductive coupling loops located below the lower insulator inductively coupled to the one or more secondary inductor coils.

2. The NMR probe of claim 1 , further comprising one or more resonators located below the lower insulator, where at least one of the one or more secondary inductor coils is coupled to the one or more resonators, where the one or more resonators split the primary resonance mode into at least two modes, where the one or more resonators comprise an inductor and a capacitor in parallel.

3. The NMR probe of claim 1 , further comprising a resonator including an inductor and a capacitor in parallel located below the lower insulator, where the resonator acts as a high frequency block, where the high frequency block does not overlap with the primary resonance mode.

4. The NMR probe of claim 1 , further comprising one or more components located above the lower insulator selected from the group consisting of one or more coupling loops, one or more resonators and one or more tertiary circuits including one or more tertiary inductor coils.

5. The NMR probe of claim 4 , further comprising one or more supports located above the lower insulator for supporting one or more of the primary inductor coil and the one or more components.

6. The NMR probe of claim 4 , further comprising an upper insulator, where the upper insulator insulates one or more of the primary inductor coil and the one or more components from one or both outside magnetic fields and outside electric fields.

7. The NMR probe of claim 1 , where the primary resonance mode is between:
a lower limit of approximately 3×10 6 Hz; and
an upper limit of approximately 3×10 9 Hz.

8. A method of detecting coupling modes of a Nuclear Magnetic Resonance (NMR) signal comprising the steps of:
(A) inductively coupling a NMR probe comprising:
a primary circuit including a primary inductor coil located above a lower insulator with a primary resonance mode;
one or more secondary circuits including one or more secondary inductor coils located below the lower insulator, where the one or more secondary inductor coils are electrically connected to the primary inductor coil; and
one or both one or more inductive coupling loops located below the lower insulator inductively coupled to the one or more secondary inductor coils and one or more resonators located below the lower insulator, where at least one of the one or more secondary inductor coils is coupled to the one or more resonators, where the one or more resonators split the primary resonance mode into at least two modes; and
(B) adjusting the one or more inductive coupling loops coupling constant (k) to detect one or more of the at least two modes.

9. The method of claim 8 , where the one or more resonators comprise an inductor and a capacitor in parallel.

10. The method of claim 8 , further comprising adjusting the coupling constant with one or more shunts.

11. A Nuclear Magnetic Resonance (NMR) probe comprising:
a primary circuit including a primary inductor coil with a primary resonance mode located in a first region;
one or more secondary circuits including one or more secondary inductor coils located in a second region a distance from the first region, where the one or more secondary inductor coils are electrically connected to the primary inductor coil; and
one or more inductive coupling loops located in the second region inductively coupled to the one or more secondary inductor coils.

12. The NMR probe of claim 11 , where the distance is between:
a lower limit of approximately 10 −4 m; and
an upper limit of approximately 10 −1 m.

13. The NMR probe of claim 11 , where the one or more inductive coupling loops are inductively coupled to the two or more secondary inductor coils to split a signal from the primary resonance mode.

14. The NMR probe of claim 13 , where the one or more inductor coils split the signal to generate two or more modes.

15. The NMR probe of claim 11 , further comprising one or more resonators located below the lower insulator, where at least one of the one or more secondary inductor coils is coupled to the one or more resonators, where the one or more resonators split the primary resonance mode into at least two mode, where the one or more resonators comprise an inductor and a capacitor in parallel.

16. The NMR probe of claim 11 , further comprising a resonator including an inductor and a capacitor in parallel located below the lower insulator, where the resonator acts as a high frequency block, where the high frequency block does not overlap with the primary resonance mode.

17. The NMR probe of claim 11 , further comprising one or more components located above the lower insulator selected from the group consisting of one or more coupling loops, one or more resonators and one or more tertiary circuits including one or more tertiary inductor coils.

18. The NMR probe of claim 17 , further comprising one or more supports located above the lower insulator for supporting one or more of the primary inductor coil and the one or more components.

19. The NMR probe of claim 17 , further comprising an upper insulator, where the upper insulator insulates one or more of the primary inductor coil and the one or more components from one or both outside magnetic fields and outside electric fields.

20. The NMR probe of claim 11 , where the primary resonance mode is between:
a lower limit of approximately 3×10 6 Hz; and
an upper limit of approximately 3×10 9 Hz.

Assignees

• Jeol Ltd

Inventors

• Zens Albert

Classifications

• G01R33/34092

  RF coils specially adapted for NMR spectrometers · CPC title

• G01R33/3635

  Multi-frequency operation · CPC title

• G01R33/3642 Primary

  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 title

• A61B5/055

  involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging · CPC title