重み付け音響光学相互作用を用いた波長選択光スイッチにおけるテーパ型弾性表面波導波路の設計

抄録

Optical wavelength-selectivity in optical switches using waveguide-type collinear acoustooptic interaction is studied from the viewpoint of the sidelobe suppression. It is found that the sidelobe level can be reduced from -9.3 dB to -20 dB by weighting the coupling coefficient over the interaction region. A method to realize the sidelobe suppression by means of modifying the surface acoustic wave (SAW) waveguide is proposed and theoretically analyzed to design the SAW waveguide. A sidelobe suppression at -20 dB is realized with a SAW waveguide of a dense-flint glass strip whose width and thickness are varied accordingly in the ranges of 700-26μm, and 0.4-1.0μm, respectively, on a Y-X LiNbO₃ substrate.