| 摘要 |
PROBLEM TO BE SOLVED: To provide an amplifier having a flat gain spectrum in a wide input dynamic range. SOLUTION: The optical signal amplifier 100 receives an optical signal formed from plural optical signals having respectively different wavelength through input means 130, 5 and the received signal is amplified by input amplification stages 10, 15 and the level of the amplifier input signal is controlled to a prescribed level by an attenuation unit 30. The amplifier 100 provided with a filter 35 substentially reduces its wavelength dependency, amplifiers the controlled signal by output amplification stages 40, 45 and supplies an amplified signal to output means 50, 130. The unit 30 attenuates the amplified optical signal as a function of respective wavelength values. |
