Magnetic field shaping components for magnetic field measurement systems and methods for making and using
A magnetic field measurement system includes at least one magnetometer; and at least one flux concentrator made of a high magnetic permeability material and configured to receive magnetic field signals from a source, to concentrate the magnetic field signals or reorient the magnetic field signals in a preselected direction, and to direct the concentrated or reoriented magnetic field signals toward at least one of the at least one magnetometer. In addition to, or as an alternative to, the flux concentrator, the system can include a passive shield made of the high magnetic permeability material. The system may also include active shielding.
1. A magnetic field measurement system, comprising:
a wearable article;
at least one optically pumped magnetometer disposed on or in the wearable article; and
at least one flux concentrator comprising a high magnetic permeability material and configured to receive magnetic field signals from a source, to concentrate the magnetic field signals or reorient the magnetic field signals in a preselected direction, and to direct the concentrated or reoriented magnetic field signals toward at least one of the at least one optically pumped magnetometer, wherein the at least one flux concentrator is disposed on or in the wearable article and configured, when the wearable article is worn, to be positioned between a wearer of the wearable article and the at least one optically pumped magnetometer.
2. The magnetic field measurements system of claim 1 , wherein each of the at least one flux concentrator comprises a first end and a second end opposite the first end, wherein the at least one flux concentrator is tapered so that the first end has a larger surface area than the second end.
3. The magnetic field measurement system of claim 1 , wherein each of the at least one flux concentrator has a three-dimensional conical or pyramidal shape.
4. The magnetic field measurement system of claim 3 , wherein the three-dimensional conical or pyramidal shape is truncated at one end.
5. The magnetic field measurement system of claim 1 , wherein the high magnetic permeability material is selected from ferrite, Mu-metal, or any combination thereof.
6. The magnetic field measurement system of claim 1 , the at least one optically pumped magnetometer comprises a plurality of optically pumped magnetometers and the at least one flux concentrator comprises a plurality of flux concentrators.
7. The magnetic field measurement system of claim 6 , wherein each of the flux concentrators is configured to direct the concentrated or reoriented magnetic field signals to a different one of the optically pumped magnetometers.
8. The magnetic field measurement system of claim 6 , wherein at least two of the optically pumped magnetometers form a gradiometer.
9. The magnetic field measurement system of claim 8 , wherein one of the flux concentrators is configured to direct the concentrated or reoriented magnetic field signals toward at least one, but less than all, of the optically pumped magnetometers of the gradiometer.
10. The magnetic field measurement system of claim 1 , further comprising a passive shield disposed around the at least one optically pumped magnetometer and configured to reduce an ambient background magnetic field at the at least one optically pumped magnetometer.
11. The magnetic field measurement system of claim 10 , wherein the passive shield is made of a high magnetic permeability material.
12. The magnetic field measurement system of claim 10 , wherein the passive shield is formed in a shape of a helmet, hood, cap, or other shape conformable to a user's head.
13. The magnetic field measurement system of claim 10 , further comprising a magnetic field generator disposed around the at least one optically pumped magnetometer and configured to reduce an ambient background magnetic field at the at least one optically pumped magnetometer.
14. The magnetic field measurement system of claim 1 , further comprising a magnetic field generator disposed around the at least one optically pumped magnetometer and configured to reduce an ambient background magnetic field at the at least one optically pumped magnetometer.
15. The magnetic field measurement system of claim 1 , wherein the magnetic field measurement system is configured to operate the at least one optically pumped magnetometer in a scalar mode.
16. The magnetic field measurement system of claim 1 , wherein the magnetic field measurement system is configured to operate the at least one optically pumped magnetometer in a SERF mode.
17. A wearable magnetic field measurement system, comprising:
a plurality of magnetometers arranged in an array;
a passive shield comprising a high magnetic permeability material and disposed around the magnetometers and configured to reduce an ambient background magnetic field at the magnetometers, wherein the passive shield is shaped to fit over a body region upon which the magnetometers and passive shield are to be worn; and
a magnetic field generator disposed around the magnetometers and configured to reduce an ambient background magnetic field at the magnetometers.
18. The magnetic field measurement system of claim 17 , wherein the passive shield is formed in a shape of a helmet, hood, cap, or other shape conformable to a user's head.
19. The magnetic field measurement system of claim 17 , further comprising at least one flux concentrator configured to receive magnetic field signals from a source, to concentrate the magnetic field signals or reorient the magnetic field signals in a preselected direction, and to direct the concentrated or reoriented magnetic field signals toward at least one of the magnetometers.