APPARATUS AND METHOD FOR PRODUCING A FLAT-TOPPED FILTER RESPONSE IN A MULTIPLEX/DEMULTIPLEXER

摘要

A (de)multiplexer (10) for use in optical communications systems for multiplexing and demultiplexing an optical signal consisting of optical channel(s) of different wavelength(s) (14, 16) includes a multiplex optical waveguide propagating a plurality of optical channels and a plurality of single channel optical waveguides, each propagating a single channel. Each of the waveguides has a receiving/transmitting end. A diffraction grating (22) is optically coupled between the multiplex optical waveguide and the single channel optical waveguides for diffracting an optical signal between the receiving/transmitting end of the multiplex optical waveguide and the receiving/transmitting end of the single channel optical waveguide. The grooves (24) of the diffraction (22) have spacing which varies according to an algorithm such that a portion of the optical signal diffracted by each groove (24) is offset in a direction of dispersion relative to the portions of the optical signal diffracted by the other surfaces to broaden the transmission band at the receiving/transmitting ends of the single channel and multiplex optical waveguides.