US Patent 7366381 Optical waveguide chip and optical component comprising same

An optical waveguide chip including a core portion as an optical waveguide, a clad portion composed of a lower clad layer and an upper clad layer, and an optical fiber guide portion which is formed integrally with the clad portion for positioning a single-mode optical fiber which is to be connected with the core portion. Each portion of the optical waveguide chip is formed by creating a layer of a radiation-sensitive polysiloxane composition by photolithography. At least two kinds of radiation-sensitive polysiloxane compositions are used so that the core portion has a higher refractive index than the clad portion.