What Is a Magnetometer?
A magnetometer is a device designed to measure the strength and direction of magnetic fields. Various types are available, including those utilizing the Hall effect and electromagnetic induction. These devices have diverse applications, from ore vein detection to product manufacturing inspection and medical equipment integration.
Applications of Magnetometers
Magnetometers are used in various contexts for magnetic field measurement:
1. Detecting Magnetism Buried Underground
Used for locating ore veins or removing underground mines. Near-surface detection often employs electromagnetic induction methods, while deeper objects are detected via geomagnetic field analysis, identifying ferromagnetic object-induced distortions.
2. Medical Equipment for Testing
Applied in magnetocardiogram and magnetoencephalography examinations by measuring the body’s magnetic field.
3. Nondestructive Testing Equipment
Used in inspecting ferromagnetic materials to identify damages or defects, and in security gates at airports for detecting metallic items through induced eddy currents.
Principle of Magnetometer
Magnetometers operate using various methods:
1. Vibrating Sample Magnetometer
Measures magnetic fields by vibrating the sample in a uniform magnetic field, enabling high-speed measurements at diverse temperatures and magnetic field strengths.
2. Magnetic Field Gradient Magnetometer
Measures the sample’s magnetic field by inducing magnetization through an alternating magnetic field, extracting this force as an electrical signal.
3. Fluxgate Magnetometer
Operates on electromagnetic induction, using two coils wound around a highly permeable iron core to measure the magnetic field through the induced electric current.
Other Information on Magnetometers
Hall Element
Hall elements in some magnetometers detect magnetic fields by outputting a voltage, representing the magnetic field strength through the Hall effect-induced voltage.