Frequency referencing system and method
US4839614A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1987 |
| Grant date | Jun 13, 1989 |
| Priority date | — |
| Expiry date | May 14, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S5/0687
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A system and method of referencing frequencies of radiation from a plurality of sources, for example lasers (1,2) includes filter element (11), such as a Fabry-Perot etalon, onto which the radiation is incident. The filter element has a replicated set of passbands spaced apart in frequency. Detection means (12, 13) detects radiation passing through the filter element (11) and provides corresponding output signals. Control means (16-18, 3, 4) is responsive to the output signals from the detection means (12, 13) to control the sources (1, 2) so that the radiation transmitted through the filter element (11) is maintained substantially constant. The bandwidths of the radiation are small compared with the corresponding passbands of the filter element. The invention is particularly applicable in a communications network in which a number of sets of remote sources of radiation are referenced to a central set of reference sources.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.