Patent ID: 7092139

Claim:
An acousto-optical tunable filter, comprising: a planar optical waveguide ( 2 ) for propagation of light beam ( 14 ), and arranged sequentially along the path of the light radiation—means for forming a light beam, transducer ( 16 ) for acoustic waves suited to generate an acoustic wave ( 15 ) that is capable of interacting with the light beam waves to cause their diffraction within a predetermined wavelength range, and means for selecting a diffracted portion of the light beam, characterized in that at least one of the light beam forming means and selecting means is in the form of at least one stripe waveguide ( 3 ) disposed in a plane of the planar waveguide ( 2 ), within said waveguide itself, or in the vicinity thereof, and in the form of a multiple unit reflectors ( 10 ) that overlap an aperture of stripe waveguide ( 3 ), the relative position and inclination angle of said unit reflectors being selected to maintain a phase difference at the operating radiation wavelength for any pair of beams ( 13 ) reflected from different unit reflectors ( 10 ), where said phase difference is essentially a multiple of 2π.