초록 ▼

A resonant tag used with an electronic article surveillance system for detecting the presence of the tag within a surveilled area utilizing electromagnetic energy at a frequency within a predetermined detection frequency range includes a resonant circuit capable of resonating at a frequency within t

A resonant tag used with an electronic article surveillance system for detecting the presence of the tag within a surveilled area utilizing electromagnetic energy at a frequency within a predetermined detection frequency range includes a resonant circuit capable of resonating at a frequency within the predetermined detection frequency range. The resonant circuit includes an inductor formed at least in part on a surface of a dielectric substrate of the tag. The inductor is formed with a discontinuity or gap, causing an electrical open circuit. The open circuit is closed with a fuse secured proximate to the gap and wirebonded to the portions of the inductor proximate to the gap. The fuse is melted by a current greater than a predetermined level flowing therethrough. Such a high current may be induced in the inductor by an external electromagnetic field. Melting of the fuse causes an open circuit condition, which alters the frequency at which the tag resonates.

대표청구항 ▼

[ We claim:] [29.] An activateable/deactivateable resonant tag for use with an electronic security system having means for detecting the presence of a security tag within a surveilled area utilizing electromagnetic energy at a frequency within a predetermined detection frequency range, the tag compr

[ We claim:] [29.] An activateable/deactivateable resonant tag for use with an electronic security system having means for detecting the presence of a security tag within a surveilled area utilizing electromagnetic energy at a frequency within a predetermined detection frequency range, the tag comprising:a dielectric substrate having first and second opposite principal surfaces;at least one resonant circuit disposed on the substrate capable of resonating at a frequency within the predetermined detection frequency range, the resonant circuit including an inductor formed at least in part on one of the principal surfaces of the substrate, wherein the resonant circuit includes a gap forming an electrical open circuit condition;a fuse structure including at least one fuse strip located on a surface of a carrier and connected to first and second bonding pads of the carrier by respective wedges of conductive material, the fuse structure positioned proximate to the gap; andfirst and second wires respectively connected to the first and second carrier bonding pads and to the resonant circuit, such that the first and second wires and the fuse structure electrically close the gap, wherein a current greater than a predetermined level flowing through the fuse structure melts the fuse strip, thereby altering the resonant frequency of the resonant circuit.