Patent ID: 8693826
Filing Date: 2014-04-08
Classification: G02B

Abstract:
1. A system for writing an optical structure in a waveguide including: a splitter to split a light beam into two coherent writing beams, an optical circuit for directing the writing beams along substantially the same optical path in opposite directions such that they produce an interference pattern in an interference region substantially within the waveguide to write the optical structure, said optical circuit including at least two acousto-optic modulators (AOMs) disposed such that both writing beams propagate through each of the at least two AOMs, the AOMs being configured to enable a controllable phase shift to be applied to a light beam propagating therethrough, the two AOMs being arranged such that each AOM is adapted to shift the phase of only one of the writing beams, to thereby provide a controllable phase difference between the writing beams.