TUNEABLE OPTICAL FILTER ARRANGEMENT FOR WAVELENGTH DIVISION MULTIPLEX (WDM) NETWORK

摘要

A tuneable optical filter arrangement (54) for selecting a wavelength channel from radiation including a plurality of wavelength channels in a WDM network is disclosed. The filter arrangement comprises a moveable planar support member (58) which carries a plurality of filter elements (60a 60x). Each filter element (60a 60x) comprises a multi-layered dielectric stack (multiple Fabry-Pérot etalon) having a fixed passband corresponding a WDM wavelength channel. In operation a wavelength channel is selected by moving (translating or rotating) a respective filter element into the path of said radiation.