Patent ID: 6600595
Filing Date: 2003-07-29
Classification: H01S,H04B

Abstract:
An optical amplifier apparatus, comprising:a first optical amplifying medium that amplifies an input signal light and outputs a first amplified signal light; a second optical amplifying medium connected to the first optical amplifying medium in series for amplifying the input first amplified signal light and outputting a second amplified signal light; an optical equalizer arranged between the first optical amplifying medium and the second optical amplifying medium; pumping light sources that respectively output pumping light for pumping the first optical amplifying medium and the second optical amplifying medium; and a wavelength division multiplexing coupler arranged on either a side to which the signal light is input to the first optical amplifying medium or a side from which the second amplified signal light is output from the second optical amplifying medium for inputting the pumping light to the first optical amplifying medium or the second optical amplifying medium, wherein said optical equalizer has the dependency upon a wavelength of loss that compensates the dependency upon a wavelength of gain generated when the signal light is amplified by the first optical amplifying medium and the second optical amplifying medium, and wherein said optical equalizer includes a grating fiber having a cutoff wavelength shorter than a wavelength of said output pumping light such that no mode transformation of said pumping light occurs.