Optical fiber cable with tampering detecting means
US4859024A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 10, 1988 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Mar 10, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/4439
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An optical fiber cable with optical fibers surrounded by a first gas blocking layer which is surrounded by a second gas blocking layer spaced from the first layer so as to provide longitudinal gas flow channels between the first and second layers. The channels are filled with a gas under a pressure above atmospheric pressure so that when the second layer is punctured, there is a gas flow and/or gas pressure drop indicating such puncturing and hence, if caused by tampering, the fact of tampering. Also, devices for indicating the gas flow and/or pressure drop and alarms and/or signal transmission terminating apparatus responsive to such devices.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.