Patent ID: 7137746

Claim:
An optical transmission module for data communication by optical signals with an external optical transmission path comprising: a positioning structure with a structure for determining an alignment with said external optical transmission path; a substrate for mounting an optical element; and a light-transmitting window located between said positioning structure and said external optical transmission path and having an optical waveguide structure corresponding to said external optical transmission path and to said optical element in a direction of light transmission, wherein said positioning structure has a substrate mounting part for mounting said substrate and a light-transmitting window mounting part for mounting said light-transmitting window, as well as structures of slightly moving the substrate mounted on said substrate mounting part and the light-transmitting window mounted on said light-transmitting window mounting part so as to adjust the positions thereof relative to the external optical transmission path; and wherein said optical element is sealed in between said substrate, said light-transmitting window and said positioning structure by fixing said substrate and said light-transmitting window to said positioning structure.