Abstract: A microwave-resistant and waterproof security tag for use with food products, especially meat products. The security tag includes a pair of single, open loop conductive traces in between which is disposed a similarly-shaped dielectric layer. This combination is encapsulated within plastic membranes or covers that are sealed at their common edges. The preferred embodiment includes rectangularly-shaped single, open loop conductive traces with rounded corners and with one end of each trace forming a capacitor plate. The width of each trace is at least 1/10 of the length of the security tag.

Abstract: The present invention is directed towards a novel procedure and system for making a security tag for an aluminum-pressed, cardboard container. The method employs a system of distancing the tag from the container and a method of calibrating the tag. The tag is then inserted into a specially designed cap and spaced a given distance from the container. The product is sealed and then sold to the consumer.

Abstract: A tag and method of making it. The tag includes a first adhesive layer provided in a first predetermined pattern between a surface of a first substrate and a first conductive foil. The first pattern corresponds to a pattern for a first conductive trace, e.g., a portion of a resonant circuit. The first conductive foil is laminated, e.g., adhesively secured, to the surface of the first substrate to form a first conductive layer. A first portion of that layer is shaped, e.g., die-cut, to generally correspond to the first pattern. A second portion of the first conductive layer not corresponding to the first portion is removed, to establish the first conductive trace, with the adhesive layer confined within the boundaries of the first conductive trace. Another conductive trace is secured to the first conductive trace, with a dielectric therebetween, to form a resonant circuit.

Abstract: A tag and method of making it. The tag includes a first adhesive layer provided in a first predetermined pattern between a surface of a first substrate and a first conductive foil. The first pattern corresponds to a pattern for a first conductive trace, e.g., a portion of a resonant circuit. The first conductive foil is laminated, e.g., adhesively secured, to the surface of the first substrate to form a first conductive layer. A first portion of that layer is shaped, e.g., die-cut, to generally correspond to the first pattern. A second portion of the first conductive layer not corresponding to the first portion is removed, to establish the first conductive trace, with the adhesive layer confined within the boundaries of the first conductive trace. Another conductive trace is secured to the first conductive trace, with a dielectric therebetween, to form a resonant circuit.

Abstract: A method of making a resonant frequency tag which resonates at a predetermined frequency. The method involves providing a first conductive pattern having an inductive element and a first land and a second conductive pattern having a second land and a third land which are joined together by a link. The second conductive pattern is overlaid the first conductive pattern such that the second land is positioned over the first land. The third land is in electrical communication with the inductive element of the first conductive pattern. The formed resonant frequency tag is energized to determine if the tag resonates at the predetermined frequency. If the tag resonates properly, the third land is electrically coupled to the inductive element. If it does not, the second conductive pattern is adjusted so that overlapping portions of the first and second lands are changed, altering the capacitance to adjust the resonant tag frequency.

Abstract: A method of making a resonant frequency tag which resonates at a predetermined frequency comprises the steps of forming a first conductive pattern comprising an inductive element and a first land, the first land having a first end connected to one end of the inductive element, and a second end spaced a predetermined distance from the first end; separately forming a second conductive pattern comprising a second land and a link element, the second land having a predetermined width; placing the second conductive pattern proximate to the first conductive pattern at a first predetermined location so that the second land overlies at least a portion of the first land with a dielectric therebetween to establish the plates of a capacitive element with a first predetermined capacitance which with the inductive element forms a resonant circuit; measuring the resonant frequency of the resonant circuit and comparing the measured frequency with the predetermined frequency; if the resonant frequency does not match the prede

Abstract: A method of making a resonant frequency tag which resonates at a predetermined frequency comprises the steps of forming a first conductive pattern comprising an inductive element and a first land, the first land having a first end connected to one end of the inductive element, and a second end spaced a predetermined distance from the first end; separately forming a second conductive pattern comprising a second land and a link element, the second land having a predetermined width; placing the second conductive pattern proximate to the first conductive pattern at a first predetermined location so that the second land overlies at least a portion of the first land with a dielectric therebetween to establish the plates of a capacitive element with a first predetermined capacitance which with the inductive element forms a resonant circuit; measuring the resonant frequency of the resonant circuit and comparing the measured frequency with the predetermined frequency; if the resonant frequency does not match the prede

Abstract: A security tag includes a combination of a resonant frequency circuit with an adjacent amplification shield for enhancing output signal amplitude. The amplification shield is located adjacent to the resonant frequency circuit and is preferably in the same or substantially the same plane as the resonant frequency circuit or is in a close, generally parallel plane. In an exemplary embodiment, the resonant frequency circuit includes an inductor electrically coupled to a capacitor. The resonant frequency circuit has a center frequency and is arranged to resonate in response to exposure to electromagnetic energy at or near the center frequency, providing an output signal having an amplitude. The amplification shield is arranged to direct a portion of the electromagnetic energy to the resonant frequency circuit to amplify the amplitude of the output signal from the resonant frequency circuit.

Abstract: A method of making a resonant frequency tag which resonates at a predetermined frequency comprises the steps of forming a first conductive pattern comprising an inductive element and a first land, the first land having a first end connected to one end of the inductive element, and a second end spaced a predetermined distance from the first end; separately forming a second conductive pattern comprising a second land and a link element, the second land having a predetermined width; placing the second conductive pattern proximate to the first conductive pattern at a first predetermined location so that the second land overlies at least a portion of the first land with a dielectric therebetween to establish the plates of a capacitive element with a first predetermined capacitance which with the inductive element forms a resonant circuit; measuring the resonant frequency of the resonant circuit and comparing the measured frequency with the predetermined frequency; if the resonant frequency does not match the prede

Abstract: A method for automated identification of the correctness of the identity of an item which has an associated primary identifier of a first machine readable type includes associating a separate, secondary identifier with the item prior to the time that verification of the correctness of the item is sought, the secondary identifier being of a second, machine readable, non-contact type. The primary identifier is read using a machine to provide primary identification information. The secondary identifier is also read using a machine to provide secondary identification information. The primary identification information and the secondary identification information are compared and the identity of the item is confirmed only if the comparison results in a match.

Abstract: A method of making a resonant frequency circuit is disclosed. The method includes the steps of: (1) forming a first adhesive layer in a first predetermined pattern on a surface of a first substrate; (2) laminating a first conductive foil to the surface of the first substrate to form a first conductive layer; (3) forming a first portion of the first conductive layer in a shape generally corresponding to the first predetermined pattern; and (4) removing a second portion of the first conductive layer not corresponding to the first portion to establish a first conductive trace on the first substrate. A third conductive trace is formed on a third substrate. The third conductive trace is secured to the first conductive trace with a dielectric layer therebetween to form the resonant frequency circuit.

Abstract: A security tag for use with an electronic security system which functions within a second frequency range comprises a substantially planar dielectric substrate having first and second sides. A first conductive pattern is provided on the first side of the substrate, the first conductive pattern comprising at least a first inductive element, a first plate of a first capacitive element and a first plate of a second capacitive element. A second conductive pattern located on the second side of the substrate comprises at least a second inductive element, a second plate of the first capacitive element and a second plate of a second capacitive element with the plates of the capacitive elements being generally aligned. The inductive elements and the capacitive elements form a resonant circuit which resonates at a first frequency within a first frequency range which is outside of the second frequency range.

Abstract: 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.

Abstract: A resonant tag circuit useful as an electronic security device includes a layered planar structure having a dielectric substrate, a resonant circuit carried on both sides of the dielectric substrate and a semiconductive material having an ionizable salt dissolved therein. The semiconductor material provides a sermiconductive bridge across an activation or deactivation point in the circuit and connects the conductive circuit on both sides of the activation or deactivation point. The resonant tag circuit of this invention is stabilized against premature operation of the activation or deactivation point from electrostatic discharge.

Abstract: A security 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 dielectric substrate having first and second opposing principle surfaces, a peripheral outer edge, and a resonant circuit capable of resonating at a frequency within the predetermined detection frequency range. The security tag also includes a guard member, in one embodiment a discontinuous conductive member, effectively electrically isolated from the resonant circuit, extending along at least a portion of the peripheral outer edge of the substrate for surrounding at least a portion of the resonant circuit. The guard member electrically isolates the resonant circuit to facilitate testing of the resonant circuit during an early stage of the manufacturing process when the resonant circuit is in web form.