Improvements in or relating to optical switching

摘要

Described herein is an integrated optical device (400) having an input path and an output path (420). A waveguide (430) including a Bragg grating is located in the output path (420). A plurality of control elements are located along the waveguide (430) for providing local adjustment of the Bragg grating to compensate for manufacturing errors. The control elements are preferably thermo-optic elements, for example, resistive elements whose temperature can be changed by supplying current to them.