This is one of the latest innovations in detection metallic objects. Guards commonly use this type of detectorsfor detecting concealed weapons at security checkpoints. However, thetechnology is not very efficient in differentiating the different types ofmetals.
This technology relies onthe simple theory of echolocation. For instance, if someone were to make asound in a padded room, most of the sound would be lost. If they to repeat thesame in a room full of hard surfaces, they would experience a very powerfulecho. This is how pulse induction works. The detector usually relies on onecoil or a number of coils that work as one. This is unlike other detectors thatrelies on two complementary coils working together. Furthermore, the detectorworks by sending a short burst of powerful current through the coil(s).
This pulse then disappearsand the magnetic field quickly reverses. This then generates a short electriccurrent, which then disappears. The current generate is used to generate areport on the objects present in the ground. If there is a magnetic objectburied in the ground, it will undoubtedly interfere with the current generated.This model works well because the pulsing motion lets it detect only signals ithas generated. The greatest impediment to using metal detectors is noise fromthe surrounding. Although it is more accurate at detecting objects, it is veryhard to differentiate these objects. The detector remains one of the mostexpensive types of detectors currently in existence.