| 摘要 |
PROBLEM TO BE SOLVED: To prevent an excessive output which can occur when the setting of an optical band pass filter is changed, related to an optical amplification device comprising an APC function and an optical band pass filter. SOLUTION: A controlling method is disclosed for an optical amplification device wherein an input light is amplified, a light of optical band pass region set to an optical filter among amplified light is extracted, and the output light is adjusted to a specified level based on the extracted light. In order to change the optical band pass region set to the optical filter, the level of output light is suppressed. Then, a new optical band pass region is set to the optical filter. Further, the output light is set to a specified level. |
