Magnetometer is an instrument for measuring magnetic induction intensity. According to the principle that a small magnetic needle can deflect or vibrate under the action of a magnetic field. From the law of electromagnetic induction, it can be deduced that for a closed circuit with a given resistance R, the change of magnetic flux in the circuit can be known as long as the charge Q flowing through the circuit is measured. This is also the design principle of magnetometers. One of its uses is to detect changes in the geomagnetic field.
Magnetometers are sensors used to measure magnetic induction intensity. They are widely used in industry, agriculture, transportation, national defense, aerospace, ocean, meteorology, medical and health and other fields. In the field of geological exploration, it can be used for geomagnetic field change monitoring and geological age detection. In the field of medical and health care, it is often used to detect human magnetic field and assist in disease diagnosis. In national defense, it can be used in magnetic mine clearance, bomb detection, magnetic wave communication, magnetic probe and magnetic navigation. In outer space exploration, it is used to detect the magnetic field of celestial bodies' movement and evolution. In satellite attitude measurement and control, magnetometers can be used to measure the space magnetic field to provide satellite attitude information.