COUPLER FOR COUPLING OPTICAL WAVEGUIDE SUBSTRATE WITH OPTICAL FIBER FIXING MEMBER

摘要

A coupler for coupling an optical waveguide substrate with at least one optical fiber fixing membre having a groove for fixing an optical fiber. Without using a reinforcing plate, the strength of coupling between the optical waveguide substrate and the fixing member is enhanced, especially even if the coupler is left under high-temperature high-humidity conditions, and a thermal shock is applied to it. The optical waveguide substrate (2) has a pair of edge surfaces where an optical waveguide is exposed, and a pair of major surfaces and a pair of side surfaces between the pair of edge surfaces. A fixing member (3A) has a coupling-side edge surface (3a), an outer-side edge surface opposed to the coupling-side edge surface, a pair of major surfaces, and a pair of side surfaces (3c). The edge surface (2a) of the substrate (2) and the edge surface (3a) of the fixing member (3A) are bonded through an adhesion layer (20) of a resin adhesive. A step portion (4A) is provided between the edge surface (2a) and the coupling-side edge surface (3a). At the step portion (4A), a meniscus portion (21) made of a resin adhesive and continuous with the adhesion layer (20) is provided.