Fiber optic isolater and amplifier
US5191467A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 2, 1992 |
| Grant date | Mar 2, 1993 |
| Priority date | — |
| Expiry date | Apr 2, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/06
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A fiber optic isolator uses only one-half the amount of costly rotator material as the prior art and an isolated laser amplifier uses only one-quarter the amount of costly rotator material. An embodiment of a fiber optic isolator includes a concave reflector and a fiber holder defining first and second fiber ports that register the respective ends of first and second fibers. A polarizer is located between the first port and the reflector, an analyzer is located between the second port and the reflector, and a Faraday rotator is disposed between the polarizer and analyzer on one side and the reflector on the other side. The polarizer and analyzer have their polarization axes at a relative angle of 45.degree. while the rotator is configured to provide a 22.5.degree. rotation. The port locations, the reflector, the polarizer, and the analyzer are configured so that light diverging from the end of the first fiber and entering the first port passes through the system and is imaged at the end of the second fiber, at least for one polarization component. At the same time, light that enters the second port is prevented from leaving the first port, regardless of the polarization mode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.