| 摘要 |
PROBLEM TO BE SOLVED: To decrease a residual amplitude modulation at an exit of a phase modulator.SOLUTION: An electro-optic phase modulator 100 is provided, which includes an optical waveguide 120 configured to guide an incident light wave partially coupled to the optical waveguide 120, as a guided light wave 3 propagating along an optical path of the optical waveguide between an entrance end and an exit end of the waveguide; and at least two modulation electrodes 132 arranged parallel to the waveguide and configured, when a modulation voltage (V(t)) is applied between the modulation electrodes, to introduce a modulation phase shift that is a function of the modulation voltage into the guided light wave. The modulator further includes means 132 for electric polarization of a substrate, configured to generate in the substrate a permanent electric field capable of reducing an optical refractive index of the substrate in the vicinity 117 of the waveguide.SELECTED DRAWING: Figure 3 |
