ERBIUMDOTIERTE FASERVERSTÄRKER MIT MODIFIZIERTER SPEKTRALER VERSTÄRKUNG

摘要

An optical amplifier comprises a waveguide with one or more rejection band filters (eg gratings) 12 between the ends of the waveguide, the rejection band being matched to the peak wavelength of the gain spectrum whereby the gain response is flattened. ASE power is suppressed, for example. An interference filter (36) may be used (Fig. 6), and the waveguides may be planar with a meandering section or a periodic perturbation as filter (Fig. 7). Thin filter chips, coloured-glass, Fabry-Perot, and Bragg filters are also specified. The filter may be continuous along the waveguide and may be a dopant. The filter may narrow the spectral gain. Er or Nd-doped rare earth and s/c amplifiers are exemplified. Telecommunications and wavelength-division multiplexing applications are detailed.