Identification device in the form of a tag-like strip affixable to an article
US4990891A · kind A · utility
Inventor
Key dates
| Filing date | Dec 18, 1987 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Dec 18, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49155
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An identification device for use in electronic security systems is proposed carrying a planar resonant circuit and suiting for use as a marker means for preventing theft of articles to which it is affixed. The device comprises two counter-turning conductive paths forming CW and CCW spiral patterns (if viewed from the same side) in opposition aligned to each other turn by turn and at least one insulative layer spaced therebetween. Said layer may be absent in lateral turn-to-turn spaces or may at least have a reduced total thickness effective therein; it may at least in part configure as a sheet as well. Due to a minimized metal coverage on its real estate the resonant circuit features a low RF magnetic field deflection and hence a high in-system detectivity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.