Patent ID: 9577781
Date: 2017-02-21
CPC Classifications: H04J

Claim:
1. An optical transmission apparatus, comprising: a set of variable optical attenuators configured to independently adjust, for each respective light of a plurality of lights at a plurality of wavelengths, attenuation of the respective light, to thereby adjust output optical power of a wavelength multiplexed light that includes the plurality of lights and is output to an optical transmission line; and a control section including a processor, a field-programmable gate array and/or a circuit, configured to stop, in accordance with control in which a light of the plurality of lights in a first wavelength band is wavelength-shifted to a second wavelength band that is different from the first wavelength band, the adjusting attenuation by the set of variable optical attenuators of lights of the plurality of lights in the first wavelength band so that the set of variable optical attenuators provides a fixed attenuation to the lights of the plurality of lights in the first wavelength band at a same attenuation level as prior to the light being wavelength-shifted.