Optical waveguide element, and optical modulation device and optical transmission device using same

Abstract

To provide an optical waveguide device in which damage to a thin plate, particularly damage to an optical waveguide, is prevented. An optical waveguide device includes: a thin plate 1 that has an electro-optic effect and that has a thickness of equal to or thinner than 10 μm, an optical waveguide 2 being formed on the thin plate; and a reinforcing substrate that supports the thin plate, in which the thin plate 1 has a rectangular shape in a plan view, a dissimilar element layer 3, in which an element different from an element constituting the thin plate is disposed in the thin plate, is formed on at least a portion between an outer periphery of the thin plate and the optical waveguide 2, and a total length over which a cleavage plane of the thin plate traverses a region where the dissimilar element layer is formed, is equal to or longer than 5% of a width of the thin plate in a short side direction.

Dependencies are inferred from the claim text.