| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a matter that constant gain control of respective GBs cannot be carried out individually, and an EDFA becomes expensive because GBs doubling the number of gain equalizers are required and the EDFA has a large number of components. <P>SOLUTION: A first optical amplifier includes a GB, branches provided, respectively, at the signal light input and output stages of the GB, a monitor gain equalizer having a loss spectrum for correcting the gain spectrum deviation of the GB and equalizing the signal light spectrum of output light from the GB branched by a branch arranged at the output stage, a light receiving unit receiving the output from the monitor gain equalizer, and a gain control circuit performing constant gain control of the GB based on the light reception level depending on the output from the monitor gain equalizer of the light receiving unit. Further, a second optical amplifier having gain equalizers arranged between the plurality of first optical amplifiers is constituted. <P>COPYRIGHT: (C)2008,JPO&INPIT |
