Temperature-compensated optical filter assemblies and related methods
US6384978B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1999 |
| Grant date | May 7, 2002 |
| Priority date | — |
| Expiry date | Mar 19, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B7/006
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An apparatus and associated method are provided to compensate for temperature-induced drift in the center wavelength of an optical filter, such as an interference filter or an etalon filter. Interference filters can be used to filter out one among a number of narrow, closely-spaced channels in an optical wavelength division multiplexed (WDM) communications system. Etalon filters can be used to lock the output wavelength of distributed feedback lasers and in other related applications. The center wavelength of interference filters and etalon filters changes with both temperature and the angle of incidence of the optical beam. The apparatus and associated method of the invention use a positioner with a different coefficient of thermal expansion to adjust the angle of incidence of the filter as the temperature changes, thereby offsetting the temperature-induced center wavelength change. The invention provides temperature-compensated optical filter assemblies, add-drop multiplexers, optical networking systems, and associated methods.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.