DENSE WAVELENGTH DIVISION MULTIPLEXER/DEMULTIPLEXER BASED ON ECHELLE GRATING

摘要

A dense wavelength multiplexer/demultiplexer ("DWDM") (10) for us in opticalcommunication systems includes amultiplex optical waveguide (14) propagating a plurality of optical channels(.eta.iest;1-n) of a select channel spacing multiplexed as asingle optical signal within a select near infrared wavelength range. acollimating/focusing optic (18) is optically coupled to themultiplexed optical waveguide at a select focal length. A reflective echellegrating (20) is optically coupled to the collimating/focusingoptic (18). The echelle grating (20) has a groove spacing (d) and blaze angle(.theta. b) providing a channel spacing (d) of the multiplexedoptical signal (.eta.1-n) at the select focal length for a select order ofdiffraction. A linear array of single channel waveguides (16), eachpropagating a single channel within the near infrared wavelength range isoptically coupled to the collimating/focusing optic. Eachoptical single channel waveguide (16) has a center and a propagating end andthe propagating ends are spaced the focal length fromthe collimating/focusing optic and the centers of adjacent demultiplexedwaveguides are spaced the select channel spacing (D). Afiber pigtail harness is used to connect the multiplexer which works in aLittrow configuration.