Optical isolator with low polarization mode dispersion
US5557692A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1995 |
| Grant date | Sep 17, 1996 |
| Priority date | — |
| Expiry date | Oct 26, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S372/703
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention provides for a compensating element in the form of a birefringent plate in an optical isolator which uses a first GRIN lens to collimate the light signal from an input optical fiber, a first birefringent polarizer wedge, an optical Faraday rotator, a second birefringent polarizer wedge, and a second GRIN lens to recollimate the light signal to an output optical fiber. Polarization mode dispersion through said optical isolator is substantially reduced by arranging the fast optical axis of the plate to be perpendicular to the fast optical axis of the polarizer on the same side of the Faraday rotator as the plate and selecting the thickness of the plate in a predetermined manner. The present invention also allows for minimization of "walk-off", which also contributes to some polarization mode dispersion through the isolator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.