Patent · US Expired

Optical fiber amplifier

US6847769B1 · kind B1 · utility

2Cited by

4References

9Claims

0Family size

Assignee

Nortel Networks Limited · CA

Inventors

Alan Robinson · Harlow, GB
Jonathan King · Blieskastel, DE
Stephen James Wilson · Northampton, GB

Key dates

Filing date	Dec 15, 2000
Grant date	Jan 25, 2005
Priority date	—
Expiry date	Dec 15, 2020

Classification

Technology area (CPC H)Electricity
CPC primaryH01S3/06708
WIPO fieldOptics
WIPO sectorInstruments

Abstract

An optical amplifier comprises a doped fiber core and a cladding layer surrounding the core. The mode field diameter of the fiber is greater than 8 μm and the refractive index difference between the core and the cladding layer is selected such that the cut-off wavelength at which the fiber becomes single mode lies in the range 1000-1550 nm. This amplifier uses a large made field diameter fiber, which reduces the intensity for a specified output power. This results in reduced filtering of the low frequency components of the signal. The refractive index difference between the core and cladding is selected such that the fiber is multi-mode at 980 nm, which enables bend performance to be improved.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.