Patent ID: 7182527

Claim:
An optical transmission device comprising: a photonic element converting an electrical signal supplied from an electronic device to an optical signal sent to an optical transmission path, or converting an optical signal received from the optical transmission path to an electrical signal; a mounting board mounting the photonic element and having at least one hole or notch at a position determined with reference to a mounted position of the photonic element; and a coupling portion having a protrusion portion inserted in the hole or the notch to relatively fix a position of the mounting board, and an optical transmission path insertion port in which an end portion of the optical transmission path is inserted and which relatively fixes a position of the optical transmission path, the coupling portion optically coupling the photonic element and the optical transmission path, wherein the protrusion portion has a caulking portion in order to relatively fix a position of the mounting board, and the caulking portion is located at a tip of the protrusion portion, and the caulking portion is bent toward a direction where the photonic element is mounted, and the coupling portion has three protrusion portions separated at angles of approximately 120°, and the photonic element is provided in a center of a circumference on which the protrusion portions are symmetrically provided.