Patent ID: 8106408

Claim:
An optical semiconductor device comprising: a CAN type optical package with a plurality of lead pins attached thereto, the plurality of the lead pins extending in a direction normal to the bottom of a stem; and a flexible substrate provided with a plurality of electric conductors fixedly attached to the plurality of the lead pins for electrical continuity therebetween, wherein the flexible substrate has a first main surface with a first region where at least one electric conductor of the plurality of electric conductors is provided, and a second region where the at least one electric conductor is not provided, the second region is beyond a longitudinal end of the at least one electric conductor, the flexible substrate is bent in the vicinity of a boundary between the first region and the second region so as to form a substantially right angle with the bottom of the stem, the second region is positioned along the bottom of the stem and fixedly attached thereto, and at least one lead pin, among the plurality of the lead pins, is fixedly attached to a surface of the at least one electric conductor respectively, for electrical continuity therewith, and in a posture in which the at least one lead pin and the surface of the at least one electric conductor are substantially parallel to each other.