Miniature magnetometer and flexible circuit

Claim 1

A miniature magnetometer apparatus for use with external monitoring equipment to determine a position of a portion of a medical device located within a first magnetic field, said medical device having an elongated passageway for holding said magnetometer apparatus, comprising: an elongated flexible tape having conductors and further having a first end portion, a second end portion, an intermediate portion and a first length, said first end portion having electrical connection means for connection to said external monitoring equipment, said length related to a length of said passageway; said intermediate portion conforming to a changing form of said passageway; a substrate having a first surface and a second surface orthogonal to said first surface, said second end portion secured to said first surface and to said second surface; a first sensor means mounted on said flexible tape at said first surface, said first sensor means having a direction of sensitivity in a first direction lying in a plane of said first sensor means; second sensor means mounted on said flexible tape at said first surface, said second sensor means having a direction of sensitivity in a second direction lying in a plane of said second sensor means; a third sensor means mounted on said flexible tape at said second surface, said third sensor means having a direction of sensitivity in a third direction lying in a plane of said third sensor means, with said first, second and third directions being mutually perpendicular; and means for electrically connecting said first, second and third sensor means to said conductors to provide first, second and third output signals representative of said magnetic field components in said first, second and third directions respectively to permit determination of a location of said substrate and thereby said location of a said portion of said medical device.