Spectra-Physics has signed a three-year sales agreement to deliver 200-GHz narrow-band pass filters to a major manufacturer of dense wavelength division multiplexing devices. The 200-GHz thin-film filters -- the newest addition to Spectra-Physics' Zeroshift line of passive optical components for telecommunications -- meet all Bellcore requirements for environmental exposure and durability. The company said the filters are designed to provide exceptional insertion loss, pass-band and isolation performance in order to increase the performance of dense WDM and optical add-drop multiplexer devices. The Zeroshift filters are centered on the ITU grid and are available in a variety of grades, depending on system requirements. "A number of leading dense WDM device manufacturers have been evaluating the Zeroshift 200-GHz thin film filters, and we're pleased with this first customer win," said Patrick L. Edsell, Spectra-Physics' chairman, president and CEO. "We have focused our optics business on the telecommunications market opportunity and expect our revenue mix to reflect our progress in this market as we move through 2000 and beyond." Spectra-Physics' line of Zeroshift products also includes anti-reflection coatings on gradient index lenses and lithium niobate isolators, as well as high-reflector coatings used in erbium-doped fiber amplifiers.