Patent ID: 6344924
Filing Date: 2002-02-05
Classification: H01S,H04B

Abstract:
Optical fiber amplifiers using optical fibers to amplify optical signals which enter the amplifiers from an input port and are emitted from an output port comprising:main optical amplifiers and first gain equalizers connected to said main amplifiers between said input port and said output port; said main optical amplifiers comprising first optical fibers which amplify said optical signals, first pumping light supply means which supply a first pumping light to excite said first optical fiber, and non-reciprocal means which control the reflection of light on said input port and said output port; said first gain equalizers comprising second optical fiber for flattening a gain of a power of the optical signal to be emitted from said output port within a fixed wavelength range, said second optical fiber having a wavelength dependency of amplification characteristics substantially identical to those of said first optical fibers and a wavelength dependency of absorption characteristics substantially identical to those of said first optical fiber within a fixed wavelength range, wherein said optical signals are WDM signals; and said second optical fiber comprises a material which can perform stimulated emission and is in a state of non-inverted population.