Patent attributes
A magnetic sensor comprises an orthogonal flux-gate magnetometer having a first sensor head comprising a first magnetic core at least parallel portions of which are formed of magnetic material, and a first detection coil wound around said first magnetic core, said parallel portions of said first magnetic core being placed closely to each other. The magnetic sensor comprises a search-coil magnetometer having a second sensor head comprising a second magnetic core having a central axis placed coaxially with a central axis of the first magnetic core of said orthogonal flux-gate magnetometer, and a second detection coil wound around said second magnetic core. The first sensor head of said orthogonal flux-gate magnetometer is placed in a region in which magnetic flux density is increased through a magnet collection effect by the second magnetic core of said search-coil magnetometer.