Optical node unit, wavelength multiplexing optical transmission system, and wavelength separating method

摘要

Wavelength-multiplexed light including wavelength lights is separated at periodic intervals of wavelength by means of a periodic optical filter, thereby generating wavelength groups composed of the following wavelength lights. Then, an optical switching section selects any one of the wavelength groups and introduces the selected wavelength group into a periodic optical filter. Making the period p of the periodic optical filter different from the period q of the periodic optical filter causes the wavelength lights included in each wavelength group to be outputted at the different separation ports of the periodic optical filter. As a result, each wavelength light is separated completely from the other wavelength lights.