Waveguide type wavelength multiplexing/demultiplexing module

摘要

In a waveguide type wavelength multiplexing/demultiplexing (WDM) module, a wavelength multiplexing/demultiplexing function can be realized with a half length of the conventional directional coupling device. The waveguide type WDM module is comprised of: a common waveguide for conducting first signal light having a first wavelength and second signal light having a second wavelength; common light input/output means coupled to the common waveguide; a substrate containing a WDM unit for multiplexing/demultiplexing the first signal light and the second signal light; a first waveguide for conducting the first signal light; first light input/output means optically coupled to the first waveguide; and second light input/output means for inputting/outputting the second signal light. The WDM unit includes a directional coupling type WDM device constituted by two sets of waveguides connected to the first waveguide and the common waveguide respectively. The directional coupling type WDM device is comprised of: a first edge surface perpendicular to a waveguide for constituting a directional coupling unit at a position equal to a half of a complete coupling length with respect to the first signal light in the directional coupling unit; and wavelength selecting means arranged at the first edge surface, for reflecting the first signal light and for passing therethrough the second signal light; and the second light input/output means is comprised of coupling means for optically being coupled to the second signal light at the first edge surface. <IMAGE>