LightSmyth Technologies (Eugene, OR) offers an integrated, single-mode-compatible, coarse WDM (CWDM) multiplexer based on the company’s nanophotonic filtering technology. The unit is passively athermal and polarization insensitive to 0.2 dB. It is based on the silica-on-silicon planar waveguide format, and requires chips of only 1 square centimeter. It uses the Deep UV photolithographic patterning tools used in electronics. The multiplexer’s diffractive nanophotonic filtering engine combines the integration capabilities of gratings with the functionality of thin-film filters.