Resonant tag circuits useful in electronic security systems
US4583099A · kind A · utility
52Cited by
2References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 27, 1983 |
| Grant date | Apr 15, 1986 |
| Priority date | — |
| Expiry date | Dec 27, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D86/85
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A resonant tag circuit is provided which is useful in conjunction with an electronic security system for preventing theft of articles from a protected area. The tag circuit comprises an electrically insulating substrate having a spiral conductive path on each surface of the substrate. The spiral conductive paths are positioned to overlap each other to effect distributed capacitance. The degree of overlap of the distributed capacitance portion of the conductive paths is such that it provides at least 70%, preferably 90% and most preferably 100% of the total overlapping portions of the circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.