Using a magnetometer to image a two-dimensional current distribution

We describe a mathematical algorithm to obtain an image of a two-dimensional current distribution from measurements of its magnetic field. The spatial resolution of this image is determined by the signal-to-noise ratio of the magnetometer data and the distance between the magnetometer and the plane of the current distribution. In many cases, the quality of the image can be improved more by decreasing the current-to-magnetometer distance than by decreasing the noise in the magnetometer.