| 摘要 |
PROBLEM TO BE SOLVED: To manufacture an optical amplifier having further increased bandwidth since light amplification methods for increasing transmission capacity so far developed are limited. SOLUTION: A phosphor-doped optical fiber having a gain peak at a plurality of bands is utilized, and wavelength multiple stimulation light is allowed to enter the optical fiber to allow the wavelength multiple signal light to be subjected to Raman amplification, thus realizing a wide-band amplification, In the wide-band Raman amplifier, no wavelength multiple signal light is arranged at a non-gain band or a fine gain band being generated among a plurality of signal gain bands that are generated by wavelength multiple excitation light. The wavelength multiple signal light is arranged among the plurality of signal gain bands, and the wavelength multiple signal light is amplified using signal light at a short-wavelength side that is amplified by a wavelength multiple stimulation light source as stimulation light. The wide-band Raman amplifier is used for Raman amplification, and at the same time the non-gain band or the fine gain band of the wide-band Raman amplifier is subjected to light amplification by an Er-doped fiber amplifier. |
