Magnetic detector

摘要

A probe and method for detecting magnetic particles. In one embodiment, the probe includes a probe core having a first end and a second end, the probe core defining two regions for containing coils of wire, one of the regions being adjacent the first end of the cylindrical probe core; two sense coils, one each of the sense coils being located in a respective one of the regions; and two drive coils, one each of the drive coils being located in a respective one of the regions, wherein the regions are separated by a distance equal to or greater than the diameter of one of the coils and a source of a secondary magnetic drive field. In another embodiment, the frequency of the drive signal of the secondary magnetic drive field is less than the frequency of the drive signal of the primary drive coils.

主权项

1. A handheld magnetic susceptometry probe system for detecting a magnetic marker within a body comprising:
a probe comprising:
a probe core having a first end and a second end, the probe core defining two regions for containing coils of wire, one of the regions being adjacent the first end of the probe core;two sense coils, one each of the sense coils being located in a respective one of the regions;two drive coils, one each of the drive coils being located in a respective one of the regions, each drive coil for generating a primary alternating magnetic drive field; anda source of a secondary alternating magnetic drive field, wherein the regions of the probe being separated by a distance equal to or greater than the diameter of one of the drive and sense coils; wherein the primary alternating magnetic drive field has a frequency f0 and the secondary alternating magnetic drive field has a different frequency, f1, from that of the primary magnetic drive field; and wherein a signal is generated by the magnetic marker at a mixing frequency of f0±2nf1, where n is a whole number, in response to the frequencies of the primary and secondary alternating magnetic drive fields.