Abstract: An optical component mounting substrate which comprises grooves for holding optical fibers, other grooves for optical components being inserted and optical waveguides is produced with a press molding process. A mold having convex and/or concave surface profiles which are corresponding to the grooves and the optical waveguides to be formed on a surface of the optical component mounting substrate is used as a die in the press molding process. The surface profiles of the mold are precisely transferred onto the surface of a transparent glass base substrate, thereby forming the optical component mounting substrate having a desired surface configuration including the grooves and the optical waveguides. Optical fibers are aligned along the grooves and fixed by a light-curing adhesive.

Abstract: An optical guided-wave device with an electro optic effect is comprised of first and second substrates having first and second refractive indices wherein the second refractive index is larger than the first one. These substrates are made of a single crystal dielectric material such as lithium tantalate or lithium niobate and, if they are made of the same material, they have different crystal orientations resulting in different refractive indices. These substrates are physically bonded directly or via a thin film such as glass, silicon, silicon oxide or silicon nitride and then, the second substrate is thinned and worked to form a wave guide therein.