Patent · US Expired

Fiber optic amplifier

US4553238A · kind A · utility

74Cited by
3References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1983
Grant dateNov 12, 1985
Priority date
Expiry dateSep 30, 2003

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01S3/094069
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A pair of small diameter optical fibers are arranged in a side-by-side configuration, the first fiber providing a passive guide for pump light, and the second fiber formed of a material, such as Nd:YAG which has amplifying properties at the signal frequency. The signal to be amplified propagates through the second fiber from the active material, resulting in amplification of the signal. The first fiber is pumped from one or both ends, utilizing a cone shaped rod which is optically coupled thereto. A large diameter beam of collimated pump light enters the cone shaped rod, where total internal reflections on the cone walls compress the beam to a small, fiber-size diameter for absorption by the active fiber. The light input to the cone-shaped rod is produced by plural, high power laser diodes, and is collimated by microlenses. By utilizing the cone-shaped rod to couple light from the high power diode lasers to the pump fiber, high pump power densities can be achieved, yielding increased amplification.

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