Silica glass waveguide structure and its application to a multi/demultiplexer

A high-silica embedded channel waveguide is fabricated using low temperature glass formation, lithography, reactive ion etching, and flame hydrolysis glass deposition process. Many applications can be found such as multi/demultiplexers, couplers, high-reliability fail-safe modules, and two-way repeater transmission modules using wavelength division multiplexing. As an example application, a new guided-wave multi/demultiplexer with high stopband rejection is realized. This consists of three directional couplers of the same structure. That is, the second and the third directional couplers are connected with two output waveguides from the first directional coupler, which acts to suppress undesired optical signals