Patent ID: 8644647

Claim:
An optical waveguide device comprising: a thin plate which has an electro-optical effect and has a thickness of 30 μm or less; an optical waveguide formed in the thin plate; and control electrodes that modulate light passing through the optical waveguide by applying an electric field to the optical waveguide, wherein the optical waveguide is a ridge type optical waveguide, the control electrodes are configured to include a first electrode and a second electrode disposed to interpose the thin plate in which the optical waveguide is formed therebetween, so that the optical waveguide is positioned between the first electrode and a second electrode and within the thin plate, the first and second electrodes are disposed on opposite sides of the thin plate in which the optical waveguide is formed, the first electrode is a coplanar type electrode including at least a signal electrode and a ground electrode, and the second electrode has at least a ground electrode, and the second electrode is configured to apply an electric field to modulate light passing through the optical waveguide positioned between the first electrode and the second electrode and within the thin plate in cooperation with the signal electrode of the first electrode.