SINGLE RESONANT BAND, TUNABLE OPTICAL FIBER WAVELENGTH FILTER BASED ON LONG-PERIOD FIBER CRATING

摘要

An optical filter that is tunable over a wide portion of the spectrum, such as the infrared portion. The filter has a core (62) of silica fiber with a first cladding layer (64) of silica fiber disposed thereon. A long period grating (80) is disposed on the core (62). A second electro-cladding layer (66) is disposed on the first cladding layer. The first cladding layer (64) is ultra thin so as to support only a single resonant band over the spectral portion. The resonant band is tunable to different wavelengths in the spectral portion by a voltage applied to the second electro-optic layer (66). The electro-optic layer (66) us a copolymer that has a refractive index less than that of the silica fiber material.