All-fiber acousto-optic tunable notch filter with a fiber winding driven by a cuneal acoustic transducer

Opt Lett. 2011 Jan 15;36(2):271-3. doi: 10.1364/OL.36.000271.

Abstract

We report a type of all-fiber acousto-optic tunable notch filter consisting of a cuneal acoustic transducer and a fiber winding of four unjacketed single-mode fibers. With -32 dB peak rejection efficiency and 178 nm tunable range of the central wavelength, all of the tunable characteristics of the all-fiber acousto-optic tunable filter are kept. In addition, the structure is versatile and convenient for use in building other complicated filters. As an example, a coarse comblike filter has been built by adjusting the axial strains of the unjacketed fibers.