We are surrounded by magnetic fields. Televisions, computers, audio speakers and many other common household items all generate electrical current. Earth also has its own magnetic field, which, in relative terms, is fairly small, so measuring it is quite a delicate process.
A magnetometer is one of two things – a device used to measure the strength, and sometimes also the direction of a magnetic field, or an entire system that measures magnetic fields using one or more sensors.
How Do They Work?
All materials that distort magnetic flux lines are referred to as being magnetic. Some materials have high magnetic conductivity, while others, such as magnetite, have their own magnetic fields.
Magnetometers work by measuring magnetic flux density, which, in the air, is directly proportional to magnetic field strength. They can therefore detect the fluctuations and distortions in the Earth’s magnetic flux that these materials create.
There are two types of magnetometers:
* Vector – which measure the flux density value in a specific direction in three-dimensional space.
* Scalar – which measure the magnitude of the vector passing through the sensor, regardless of the direction
Uses of Magnetometers
Magnetometers have many uses including:
* Indicate the location of deposits of magnetic ore such as iron ore, or of geological formations associated with petroleum.
* Security screening at airports – magnetometers will detect concealed guns or other metallic weapons.
* Smart phones and tablets – the magnetometer measures the Earth’s magnetic field which, when combined with gravity, determines the three- dimensional orientation in which the phone is being held. This information is then used to give the phone or tablet user useful information, such as locating the nearest subway stations, as a phone is moved around. A compass app can translate magnetic north into true north, if the phone also knows its rough geographical location.
* Located on spacecraft that explore planets.
* Used by the military to detect submarines. The US, Canada and Australia have classified some of the more sensitive magnetometers as military technology, and control their distribution.
* Ground-based and airborne electromagnetic geophysical surveys.
* Detecting shipwrecks, archaeological sites and other submerged or buried objects.
* Directional drilling for oil and gas.
Watson Industries experienced team of design engineers manufactures a wide range of sensors, including magnetometers, with applications ranging from undersea to outer space. Visit us for more information.
