| 摘要 |
The purpose of the present invention is, in a waveguide type optical element, to effectively prevent the acceleration of drift generated by a higher electric field applied to a substrate through a bias electrode. The waveguide type optical element comprises: a substrate (100) that has an electro-optic effect; two optical waveguides (104, 106) that are arranged in the surface part of the substrate; a non-conductive layer (120) that is arranged on the substrate and is composed of a material having a lower dielectric constant than the substrate; and a control electrode (150) that is arranged on the non-conductive layer and is for generating a difference in refractive index between the two optical waveguides by applying an electric field on each of the two optical waveguides. The non-conductive layer is composed of a material that contains silicon oxide, indium oxide, and titanium oxide with a ratio of the molar concentration of titanium oxide to the molar concentration of indium oxide set to 1.2 or greater. A voltage is applied to the control electrode to generate an electric field of 1 V/μm or greater in the substrate. |
