Security element for the electronic surveillance of articles
US6690279B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Jan 28, 2000 |
| Grant date | Feb 10, 2004 |
| Priority date | — |
| Expiry date | Jan 28, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2448
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The invention is directed to a security element for the electronic surveillance of articles. This security element is detected by surveillance systems operating in different frequency ranges and it includes at least two materials of high permeability which, when excited by an external alternating magnetic field emit each a characteristic signal. The maximum signal components of the two materials lie in different frequency ranges and the signal components of the one material are negligibly ow in that particular frequency range in which the signal component of the other material is at a maximum level. The invention also relates to surveillance systems that incorporate these security elements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.