| abstract |
A marker (10) for use in magnetic-type electronic article surveillance systems, comprising a substrate (12) on which are deposited a plurality of high permeability, low coercive force magnetic thin-films (14, 18, 22, 26, 30, 34), each being separated from an adjacent magnetic thin-film by a non-magnetic thin-film (16, 20, 24, 28, 32). Each of the magnetic films have substantially the same permeability and coercive force, and the non-magnetic films are of a thickness to allow magnetostatic coupling while inhibiting exchange coupling. Accordingly, all of the magnetic thin-films reverse as a single entity and produce a sharp, readily distinguishable response. |