| 摘要 |
PURPOSE:To provide an optical fiber amplifier capable of ensuring a maximum amplification by independently separately adjusting excitation laser diodes even when variations of characteristics of those laser diodes take place. CONSTITUTION:(n-1) Excitation laser diodes 4, 5, 6 connected to rare-earth doped fibers 3 are controlled constantly at their output levels by APC circuits 9, 10, 11, respectively. An output of an optical fiber amplifier is monitored, with reference to which output the output level of a remaining one excitation laser diode 7 is controlled constantly by a constant output control circuit 12. |
