Patent ID: 6342835
Filing Date: 2002-01-29
Classification: G01V,G08B

Abstract:
A magnetic detection apparatus for sensing an object in a sensing region, the apparatus including:a magnetic field generating means for producing a magnetic field within said sensing region in response to a source signal; a plurality of magnetic receiving elements arranged in a matrix, said matrix comprising an array of receiving elements arranged in rows and columns on a same side of said sensing region, each magnetic receiving element being responsive to changes in the magnetic field within the sensing region to provide an output signal; cancellation means for generating a feedback signal adapted to minimize spurious magnetic effects of the magnetic field generating means on the output signals of the magnetic receiving elements; and signal processing means for processing said output signals of the magnetic receiving elements and for producing an image corresponding to variations produced in said output signals by the object in the sensing region whereby, in use, an indication of the location and approximate shape of the object in the sensing region can be obtained.