Fibre-optic lasers and amplifiers
US4955025A · kind A · utility
Inventors
Key dates
| Filing date | Mar 20, 1989 |
| Grant date | Sep 4, 1990 |
| Priority date | — |
| Expiry date | Mar 20, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B6/29395
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An active device (FIG. 1) comprising a length of doped fiber (1) and an end-coupled pump source (11). The fiber (1) is of single-mode geometry and incorporates rare-earth or transition metal dopant ions. These latter are incorporated at a low-level uniform concentration (.ltorsim.900 ppm). The fiber host (1) selected exhibits an inherently ultra low attentuation loss (.ltorsim.40 dB/km) at the emission wavelength. The fibers (1) are generally of long length (e.g. 5 m to 300 m) and may be coiled for compact packaging. The fiber (1) may be formed as part of a Fabry-Perot cavity (1, 7, 9); or, as a ring cavity (FIG. 8) using a doped fiber coupler (29) spliced to form a ring (27). Q-switch and mode-locking devices (19) and gratings (25) may be included as part of the Fabry-Perot cavity to allow pulse-mode operation and/or wavelength tuning, respectively. The fiber (1) may also be utilised as an amplifier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.