A security fence where in a frame there is provided a netting of a single continuous weft-knitted optical wire attached under tension to said frame, where one end of the wire is connected to a light source and the other to a light receiver. Any abrupt change in the intensity of the light passing through...http://www.google.fr/patents/US5592149?utm_source=gb-gplus-shareBrevet US5592149 - Security fence
