Abstract
Metal detector systems are widely using in current daily life. Nowadays, metal detectors operate on three basic technologies: very low frequency (VLF), pulse induction (PI), and beat-frequency oscillation (BFO). They are commonplace in libraries, airports, military camp, prisons, stores and shops. However, these devices share the common disadvantages of not being able to detect the profile of metal object. To resolve these problems, we recently developed a compact metal detector capable of differentiate metal of different shapes and geometry using a fiber-optic magnetostriction sensor. The basic concept of the metal detection is based on monitoring strain-induced optical path length change in the interferometer stems from the magnetic field induces magnetostriction effect on the ferromagnetic material which is coated on optic-fiber. Metal detection is made possible by disrupting the magnetic flux density present on the magnetostrictive sensor. In this paper, we will present our approach and the latest result of 2D metal profile measurement.