Abstract

The present invention consists of an apparatus comprising a signal sending line which has a folded-back shape, and which serves to send a current for generating a magnetic field; and a signal receiving line which has a folded-back shape, which is arranged at a position permitting it to be electromagnetically coupled with the signal sending line, and which serves to detect a magnetic flux change caused by the approach of metal. The plurality of signal sending lines are arranged coplanarly, while the plurality of signal receiving lines are arranged coplanarly. The signal sending lines and the signal receiving lines are arranged with their planes held in parallel and in directions intersecting to each other, thereby constructing a sensing matrix. The sensing matrix is arranged in opposition to a panel along which a metal body to be detected moves, while holding therebetween a space which is, at least, large enough to pass the metal body. Signal sending means and signal receiving means are connected to the sensing matrix so as to detect the location the metal body.