Multiple pulse responder and detection system and method of making and using same
US5304983A · kind A · utility
9Cited by
12References
18Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 4, 1991 |
| Grant date | Apr 19, 1994 |
| Priority date | — |
| Expiry date | Dec 4, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/2471
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A responder for electronic article surveillance apparatus is made by subjecting a plurality of magnetizable elements to heating in the presence of a magnetic field and maintaining the field at a different intensity for each element as it is cooled to provide different magnetic characteristics so that when the responder is subjected to a cyclically varying magnetic interrogation field its several elements produce spaced apart pulses in each cycle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.