Integrated sensor system for measuring electric and/or magnetic field vector components

#1. Field of the Invention

#The present invention pertains to measuring at least magnetic fields and, more particularly, to an integrated sensor system for measuring vector components of magnetic fields, preferably along with electric fields.

#2. Discussion of the Prior Art

#FIG. 1 is a perspective view of an integrated electric (E) and magnetic (B) field sensor constructed in accordance with a preferred embodiment of the invention;

#FIG. 2 is a perspective view of an integrated E and B sensor system constructed in accordance with another embodiment of the invention that measures non-orthogonal components of electric and magnetic fields;

#FIG. 3 is a perspective view of an integrated sensor constructed in accordance with a still further embodiment of the invention; and

#The present invention provides advances in connection with establishing a compact sensor system that can measure multiple vector components of both electric and magnetic fields at very high sensitivity. By a “compact” sensing system it is meant that the region over which a particular field is measured is small relative to the spatial variations in the field that are of interest, and/or is sufficiently compact that a system that measures multiple components of the field is of a convenient size. As will become fully evident below, the compact nature and arrangement of the various sensors allows the sensors to intersect at a common center, while enabling minimum lateral offsets between the sensors.

#An example of a multi-axis, combined E-field and B-field sensor system 300 built according to a preferred embodiment of the invention is shown in FIG. 1. In this system, three orthogonal axes of an electric field are measured with various capacitive sensors 330–335 arranged as pairs in orthogonal oriented directions. To measure the electric field, it is only necessary to measure the potential at two points, subtract one result from the other, and divide by the physical distance, d, between the two points, and multiply by a calibration constant k which is close to unity to allow for the design of the sensor, with k being readily determinable by testing the sensor in a known field.

#E = k ⁢ V 1 - V 2 d [ 1 ]