Optical amplifier gain control
US5117196A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 1990 |
| Grant date | May 26, 1992 |
| Priority date | — |
| Expiry date | Apr 23, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01S3/094003
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The gain of an optical amplifier is maintained constant by employing a portion of the amplified optical signal in a feedback loop. In one arrangement this is used to control the output of a pump signal source accordingly. The portion of the said signal corresponds to spontaneous emission (ASE) at a control wavelength or band of wavelengths different to the wavelength of the optical signal output. In the case of an erbium, for example, optical fibre amplifier the portion is preferably ASE at 980 nm, the amplified signal being at 1.535 .mu.m, i.e. completely different transitions in the amplifying medium are used for gain and ASE feedback in order to lessen requirements on the filter used to extract the portion for the feedback loop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.