Patent ID: 6972562

Claim:
A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample, comprising a fiber optic for transferring incoming linearly polarized light from a source thereof to said particle and for transferring reflected light from said particle, said fiber optic having a reflective material trapping light within said fiber optic, and a light detector in communication with said fiber optic for determining the polarization of light reflected from said particle as a function of the strength and direction of the magnetic field of the sample, whereby linearly polarized light from the source thereof transferred to said particle positioned proximate the sample is affected by the magnetic field of the sample sensed by said particle such that the difference in polarization of light entering and leaving said particle is due to the magnetic field of the sample.