An optical transmission module is disclosed that comprises an optical element having an optical path formed therein, optical connection parts respectively arranged on both sides of the optical element so as to connect the optical element to plural optical fibers, and reinforcement parts. A BGA package includes a stiffener, substrate, a silicon die, and solder balls. The milling tool has a rotary cutter bit that can be controlled for longitudinal and rotational position and depth of cut from the proximal end of the tool. A positioning boss is provided in the bottom face of the clamper and inserted into the circular hole. The signal generator section produces a pair of complementary dynamic logic output signals dependent upon the dynamic logic signal and the first and second delayed clock signals.