Optical demultiplexer/multiplexer

摘要

An optical demultiplexer/multiplexer, for a signal of n wavelengths lambda 1 to lambda 4 comprising: a filter unit in which n-1 wavelength selective transmission/reflection optical filters F0 to F2 are disposed in parallel on two opposite sides of a block; an external light input/output port E0 disposed outside the filter unit and positioned on the reflecting light axis of the filter F0; and a plurality of light input/output ports P1 to P3 disposed on the transmission light axes of filter F1 and F2 and on the reflecting light axis of filter F2. The device further comprises transmission/reflection optical filter F0 which transmits lights of all wavelengths lambda 2 to lambda 4 corresponding to the light input/output ports P1 to P3 but reflects light of wavelength lambda 1. <IMAGE>