Alignment of a Vector Magnetometer to an Optical Prism

TL;DR

This paper introduces a novel method for aligning a vector magnetometer with an optical prism, enabling absolute magnetic field direction measurement with high precision, surpassing traditional relative angle techniques.

Contribution

The paper presents a new alignment technique that allows for absolute magnetic field direction determination using optical comparison, improving precision over existing methods.

Findings

Achieved alignment precision better than 500 μrad.

Determined coil orthogonality errors with similar precision.

Measured relative sensitivity of the magnetometer axes at 5×10^{-4}.

Abstract

A method for alignment of a vector magnetometer to a rigidly attached prism is presented. This enables optical comparison of the magnetometer axes to physical surfaces in an apparatus, and thus an absolute determination of the magnetic field direction in space. This is in contrast with more common techniques, which focus on precise determination of the relative angles between magnetometer axes, and so are more suited to measuring differences in the direction of magnetic fields. Here we demonstrate precision better than 500 $\mu$rad on a fluxgate magnetometer, which also gives the coil orthogonality errors to a similar precision. The relative sensitivity of the 3 axes is also determined, with precision of about 5$\times 10^{-4}$.