Near field presence detection device
US7151451B2 · kind B2 · utility
14Cited by
3References
17Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 2, 2004 |
| Grant date | Dec 19, 2006 |
| Priority date | — |
| Expiry date | Jun 28, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03K2217/94005
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The invention relates to a near field presence detection device provided to monitor an area (11) around a mouth (2) of a reading member, in particular a card reading member (1). The device comprises a presence detector (3) including a transmitter (4) and a receiver (5), said detector is provided to detect a change of field impedance due to a foreign object in the area (11). The device is further provided to generate a preliminary alarm signal and an effective alarm signal if preliminary alarm signal subsists within a predetermined time period.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.