Abstract: Disclosed is a &pgr;-shifted optical grating device based on electro-optically induced waveguide gratings. The waveguide has a core and a cladding where the core or the cladding is made of an electro-optic material. A plurality of electrodes are placed on one side of the waveguide and at least one electrode is placed on the other side of the waveguide. A voltage pattern is selectively applied to the electrode so that the pattern induces at least one &pgr;-shifted grating in the waveguide when the pattern is applied.

Abstract: A diffraction grating for a waveguide or for externally incident light. The grating includes a substrate and an electrooptic structure extending over it. The electrooptic structure may include a waveguide having a propagation axis. A first and a second electrode structure are provided on either side of the electrooptic structure so that an electric field is generated in the electrooptic structure when a potential is applied to the electrodes. The first electrode structure has an interdigitated configuration defining a plurality of fingers. In use, respective potentials V0 and V0+&Dgr;V are applied to adjacent fingers. The diffraction grating induced in the electrooptic structure by the periodic electric field advantageously has a refractive index adjustable by varying V0 and &Dgr;V and a spatial periodicity adjustable by varying &Dgr;V.