Optical fiber intrusion location sensor for perimeter protection of precincts
US4931771A · kind A · utility
37Cited by
6References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 27, 1988 |
| Grant date | Jun 5, 1990 |
| Priority date | — |
| Expiry date | Sep 27, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/186
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A Precinct Protection System includes a laser source of light which is applied at the input to a bundle of light transmissive fibers. The fibers are gathered in a cable in loops of varying lengths so that the fibers enter and exit the cable at one and the same end. The cable is placed along a line adjoining or surrounding the precincts to be protected. An intruder traversing the line or protected perimeter will disturb one or more of the fiber optic loops of the cable. The circumstance and locality of the disturbance produced by the intruder are indicated on an analog or digital display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.