| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a Raman amplifier in which a gain bandwidth is not restricted even when a signal light beam flat gain is enlarged more than heretofore. SOLUTION: A Raman amplifier has an optical fiber 100, an excitation light source 300 which excites the optical fiber 100 from the front where a signal light beam is made incident, an excitation light source 302 which excites the optical fiber 100 from the back, a multiplexer 200 which multiplexes exciting light and the signal light beam from the excitation light source 300, and a multiplexer 202 which multiplexes exciting light and the signal light beam from the excitation light source 302. The excitation light sources 300 and 302 have respectively a plurality of exciting light wavelengths, and the exciting light wavelength of the excitation light source 300 differs from the exciting light wavelength of the excitation light source 302.</p> |
