Optical beamsteering using integrated optical modulators

A device has been designed and fabricated to demonstrate the principle of using the interference pattern of a number of coherent optical sources to form and steer an optical beam. Steering of the beam can be accomplished by varying the relative phase of the constituent sources. The effect of relative source phase variation and source separation variation has been considered and optimized using a multiple source interference model. In this case the constituent sources are the outputs of integrated optical waveguides, excited by a common optical source to maintain relative coherence. In order to demonstrate the principle of beamsteering, a device with two constituent sources (waveguides) has been fabricated, and the resultant output interference pattern has been laterally translated by varying the phase of the output of one waveguide with respect to the other, via a novel optical phase modulator.