| 摘要 |
PROBLEM TO BE SOLVED: To obtain an optical amplifier having a wide band and simple constitution in a system having the optical amplifier. SOLUTION: The optical amplifier is provided with a 1st optical amplifier 14 for a 1st band (e.g. a conventional band: C band), a 2nd optical amplifier 16 for a 2nd band (e.g. a long wavelength band: L band), an optical demultiplexer 20 and an optical multiplexer 24 for connecting the 1st and 2nd optical amplifiers 14, 16 in parallel, and a control unit for controlling the 1st and 2nd optical amplifiers 14, 16 so as to keep optical power on an output port constant. In the constitution, a wide band amplification can be obtained by adopting the 1st and 2nd optical amplifiers 14, 16 and the constitution can be simplified by using the control unit for both the 1st and 2nd optical amplifiers 14, 16. |
