Optical add/drop multiplexer

摘要

An optical add/drop multiplexer of the invention includes: a wavelength blocker for blocking signal light having at least one wavelength out of a plurality of signal lights included in WDM light supplied from a transmission line and passing the other signal light; an optical coupler for multiplexing signal light having the same wavelength as that of the signal light blocked by the wavelength blocker to signal light passed through the wavelength blocker; a WDM amplifier for amplifying the WDM light multiplexed by the optical coupler and outputting the amplified light; and an optical branch coupler for branching the WDM light output from the WDM amplifier into two lights, extracting signal light having at least one wavelength different from the wavelength of signal light multiplexed by the optical coupler from one of the branched lights, and outputting the other branched light to the transmission line. With the configuration, a small and cheap optical add/drop multiplexer as a flexible OADM node can be provided.