Application of photorefractive fiber and waveguide gratings to fast speed narrow band tunable filters

摘要

In this paper, the progress of the application of photorefractive fiber and waveguide crystal gratings to a narrow band, fast speed, tunable filter is presented. This novel filter is based on tunable Bragg grating. It uses the diffraction effect of Bragg grating to select the wavelength and the electro-optic effect of the grating to tune the effective grating period. Several approaches of fabricating this type of tunable Bragg grating based filter are discussed and some preliminary results are discussed and some preliminary results are provided. It is shown that the tuning speed of this type of filter can be in the ns range and the bandwidth can be as narrow as 0.01 nm.