US 12,265,310 B2
Optical waveguide device, optical modulator, optical modulation module, and optical transmission apparatus
Yu Kataoka, Tokyo (JP); and Kosuke Okahashi, Tokyo (JP)
Assigned to SUMITOMO OSAKA CEMENT CO., LTD., Tokyo (JP)
Filed by SUMITOMO OSAKA CEMENT CO., LTD., Tokyo (JP)
Filed on Mar. 21, 2022, as Appl. No. 17/699,595.
Claims priority of application No. 2021-050409 (JP), filed on Mar. 24, 2021.
Prior Publication US 2022/0308418 A1, Sep. 29, 2022
Int. Cl. G02F 1/225 (2006.01); G02F 1/21 (2006.01)
CPC G02F 1/2255 (2013.01) [G02F 1/212 (2021.01)] 11 Claims
OG exemplary drawing
 
1. An optical waveguide device comprising:
a substrate;
an optical waveguide formed on an upper surface of the substrate;
two electrodes disposed at positions sandwiching the optical waveguide from both sides in a plane of the substrate; and
a dielectric layer covering a top surface of the optical waveguide, wherein
each of the two electrodes includes a first stage electrode disposed on the upper surface of the substrate and a second stage electrode disposed on an upper surface of the first stage electrode, the first stage electrode and the second stage electrode are formed in a stepped shape in which the first stage electrode is wider than the second stage electrode in a width direction of the optical waveguide,
the dielectric layer extends to an extent including edges of the two electrodes, facing the optical waveguide, in the width direction of the optical waveguide, and is disposed to partially cover the upper surface of each of the first stage electrodes, and
a gap is formed between the dielectric layer and each of the second stage electrodes in the width direction of the optical waveguide.