APPARATUS AND METHOD FOR IMAGING THE STRUCTURE OF DIAMAGNETIC AND PARAMAGNETIC OBJECTS

摘要

The surface of internal structure of diamagnetic and paramagnetic materials is imaged by measuring, preferably with a superconducting quantum interference device (SQUID) magnetometer (7), perturbations to an applied magnetic field resulting from variations in magnetic susceptibility at an array of locations across the object (3). The array of perturbation measurements is processed to generate a map of local susceptibilities. For implementation of susceptibility tomography, multiple arrays of perturbation signals for a plurality of relative orientations between the object, the field, and the measurement locations are processed to generate values for local susceptibility at selected sites within the object, such as along a selected sectional plane.