Magnetometer with structure asymmetry correction

• US 20040196035A1
• Filed: 01/26/2004
• Published: 10/07/2004
• Est. Priority Date: 08/16/2001
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Guilhamat, Bernard, Leger, Jean-Michel
• Granted Patent: US 7,123,005 B2
• Time in Patent Office: Days
• US Class Current: 324/253
• CPC Class Codes: G01R 33/045 in single-, or multi-aperture elements

Abstract

A differential magnetometer consisting of at least one active coil (4, 5) and a receiver coil (10) for which the windings are installed differentially, is provided with a measurement circuit (14) with a slaving device that corrects dissymmetry appearing between windings (11, 12) to eliminate residual induction at the frequency of the magnetic excitation field, intended to make the measurement coil (10) more sensitive without applying a voltage to it.

Claims

1. Magnetometer comprising a magnetic core, at least one active coil (4,5) and a receiver coil (10), the active coil being arranged so as to create a magnetic excitation field in the core, the receiver coil having two windings (11, 12), means of passing an alternating current at an excitation frequency in the active coil and means (14) of measuring a voltage induced in the receiver coil, characterised in that the measurement means comprise a detector (27) of a synchronous component at the excitation frequency of the induced voltage, a circuit with two loops (21, 22) each of which comprises a winding of the receiver coil, an adder (25) of partial voltages at the terminals of the two loops and a device for correction (28) of one of the said partial voltages, slaved to the said detector.

2. Magnetometer according to claim 1, characterised in that the correction device (28) is a variable resistance.