Optical waveguide devices

摘要

It is provided an optical waveguide device in which the radius of curvature of a curved part of an optical waveguide can be lowered and the radiation loss of light in the curved part can be reduced. An optical waveguide device (2) has a ferroelectric optical waveguide substrate and an optical waveguide (5) formed in or on the substrate and modulating electrodes (4A,4B and 4C). The thickness of the optical waveguide substrate is 30 µm or smaller at least in a region where the optical waveguide is formed. The optical waveguide has curved part (5c,5d) having a radius of curvature of 30 mm or smaller.