Simplified acousto-optic deflector using electronic delays

An acousto-optic deflector comprising:

• means for projecting a beam of substantially monochromatic light along a predetermined path;
• a light-sound interaction device comprising an acoustic-wave transmitting medium and transducer means coupled to said medium for propagating therein, across said predetermined path, sound waves in a direction longitudinally related to said path but inclined thereto at an angle selected to provide Bragg diffraction of said light beam, said transducer means comprising a transducer element bonded to one edge of said medium in a substantially planar arrangement;
• a plurality of electrodes coupled to said transducer element, the length L of each electrode and gap g therebetween being selected to optimize diffraction efficiency of the light as it interacts with said sound waves as the deflection angle between said predetermined path of monochromatic light and said sound waves is caused to change;
• and
• means for applying an RF drive signal to said plurality of electrodes, said drive signal being applied directly to one of said plurality of electrodes and coupled to each of the other electrodes via means for electronically delaying said drive signal.