Patent ID: 7424188

Claim:
An optical module, comprising: a first optical waveguide part including a first waveguide core; a second optical waveguide part including a second waveguide core; an electro-optic material layer provided between said first and second waveguide cores and formed from an electro-optic material; and an electrode for applying an electric field to said electro-optic material layer so that the refractive index of said electro-optic material layer varies and the optical coupling coefficient between said first and second waveguide cores varies thereby an optical coupling efficiency is improved; wherein said first and second waveguide cores sandwich said electro-optic material layer in the vertical direction such that a light propagated through one of said first and second waveguide cores propagates to the other of said first and second waveguide cores via only said electro-optic material layer, and said electrode is comprised of a negative and a positive electrode, and said negative and positive electrode are provided on the opposite sides of a portion of said electro-optic material layer between said first and second waveguide cores so as to sandwich the portion of said electro-optic material layer in the horizontal direction.