Apparatus and method for controlling the spectral response of a waveguide bragg grating

摘要

The present invention provides a method and apparatus for controlling the spectral response of an optical waveguide (30, 40) Bragg grating by control of the strain distribution or temperature distribution imposed along the grating. The precise strain gradient is, for example, produced by a set of independently controlled transducers (44), such as piezoelectric, magnetostrictive, thermo-electric actuators, distributed along the length of the grating. In another embodiment, the Bragg grating (33) is bound to or embedded in a cantilever beam (32) subjected to bending, twisting or tensing. Controlled waveguide Bragg gratings according to the invention can be used to compensate for the dispersion experienced by short optical pulses as they propagate along an optical fiber. They can be tuned and chirped over a broad spectral range with or without a shift in the grating center wavelength. In addition, they can be used to manufacture a variety of spectral filters.