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

Abstract

Provided is an optical waveguide element whereby it is possible to prevent dropout of an optical component due to internal stress that occurs in a joint between the optical component and an optical waveguide member including a substrate on which an optical waveguide is formed, and to simplify a manufacturing step pertaining to polishing of a joining surface. An optical waveguide element comprising: an optical waveguide member including a substrateon which an optical waveguide is formed; and an optical componentthat is fixed to an optical waveguide member end surface (B) on which an input part or an output part of the optical waveguide is disposed, and that transmits input light inputted to the input part or transmits output light outputted from the output part, wherein the optical waveguide element is characterized in that portions (B, B) having greater roughness than the end surface (B) of the optical waveguide member including the input part or the output part are provided in at least a portion of the optical waveguide member, which is the portion thereof to which the optical componentis fixed.