Patent ID: 8452138

Claim:
An optical sensor module, comprising: an optical waveguide unit; and a board unit mounted with an optical element and coupled to the optical waveguide unit; wherein the optical waveguide unit includes an under-cladding layer, a linear core provided on a surface of the under-cladding layer and serving as an optical path, an over-cladding layer covering the linear core, a single edge extension portion extending along one side edge of the over-cladding layer axially of the core, a board unit engagement groove provided in the single edge extension portion, and a projection projecting from a side wall of the groove and kept in abutment against an engagement portion of the board unit; wherein the board unit includes a substrate, an optical element mounted on a predetermined portion of the substrate, and the engagement portion provided in a portion of the substrate and fitted in the board unit engagement groove of the optical waveguide unit; wherein the optical waveguide unit and the board unit are coupled to each other with the engagement portion of the board unit being fitted in the groove of the optical waveguide unit and with the projection in abutment against the engagement portion within the groove such that the light transmission face of the linear core and the optical element are aligned with each other; wherein the projection includes projections provided on opposed side walls of the board unit engagement groove so that a recess defined between adjacent ones of projections provided on one of the opposed side walls is opposed to a projection provided on the other side wall.