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Description:
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All -fiber multireflector spectral filters which have potential application in
optical communications have been investigated experimentally . These multireflector etalons were produced by aligning equal -length fiber sections with TiO2 /SiO2 dielectric mirrors deposited on the end in a silicon v -groove .
Fiber sections 1 .33mm in length were produced by polishing , with the fibers held in a silicon wafer polishing jig . The fibers were aligned inside the polishing jig using a precision micro positioner . Then four polishing steps with increasingly finer grit were applied to produce high -quality polished end surfaces on each fiber section . Finally , a dielectric mirror was deposited on one end of each fiber section by magnetron sputtering .
After characterizing the optical loss , length , and mirror reflectance for each of the fiber sections , sections which were well -matched in length were chosen for assembly of the four -mirror etalon , which had nominal reflectance values of 10 % , 50 % , 50 % , and 10 % for the dielectric mirrors . Measured transmittance spectra for a mutireflector spectral filter were compared with calculated spectra .
Thermal tuning of the multireflector etalon was also investigated . A 0 .34 nm wavelength shift was observed for a 23° C temperature change , in agreement with prediction .
increasingly finer grit were applied to produce high -quality polished end surfaces on each fiber section . Finally , a dielectric mirror was deposited on one end of each fiber section by magnetron sputtering .
After characterizing the optical loss , length , and mirror reflectance for each of the fiber sections , sections which were well -matched in length were chosen for assembly of the four -mirror etalon , which had nominal reflectance values of 10 % , 50 % , 50 % , and 10 % for the dielectric mirrors . Measured transmittance spectra for a mutireflector spectral filter were compared with calculated spectra .
Thermal tuning of the multireflector etalon was also investigated . A 0 .34 nm wavelength shift was observed for a 23° C temperature change , in agreement with prediction . |