Optical element combination structure

An optical element combination structure in which an optical fiber and an optical waveguide are combined with each other comprising:

• an optical fiber which extends to an optical fiber end surface in a direction of an optical axis and has an optical fiber core extending along the optical axis;
• an optical waveguide having an optical waveguide core aligned with the optical fiber core in the direction of the optical axis and an optical waveguide end surface facing the fiber end surface;
• and
• a substrate extending along the optical fiber and the optical waveguide in the direction of the optical axis, having a support surface which the optical fiber is supported on and secured to, and integrally formed with the optical waveguide;
• wherein the support surface is formed so that, when the optical fiber is abutted to the support surface, the optical fiber and the optical waveguide are in alignment with each other in the direction of the optical axis;
• wherein a value of refractive index of the optical waveguide core is different from that of refractive index of the optical fiber core;
• wherein the fiber end surface is formed substantially perpendicular to the optical axis, and the waveguide end surface is formed so that it is inclined relative to a surface perpendicular to the optical axis;
• and
• wherein a gap is provided between the fiber end surface and the waveguide end surface and is filled with a filler having substantially the same value of refractive index as that of refractive index of the optical fiber core.