Patents Assigned to Ibden Co., Ltd.
  • Waveguide type optical directional coupler
    Patent number: 5371812
    Abstract: Down-sized optical directional coupler with high performance and reduction of power includes a LiTaO.sub.3 monocrystal substrate, at least two optical waveguides of a LiNbO.sub.3 monocrystalline thin film formed close to and parallel to each other, and means for changing a refractive index of the optical waveguide provided on at least one of the optical waveguides, thereby obtaining a matching of a lattice constant between the LiTaO.sub.3 monocrystal substrate and the LiNbO.sub.3 monocrystalline thin film.
    Type: Grant
    Filed: November 22, 1993
    Date of Patent: December 6, 1994
    Assignee: Ibden Co., Ltd.
    Inventor: Masanori Nakamura