Abstract: A semiconductor submodule includes a substrate (10) as a first substrate having at least one hole, and at least one optical semiconductor device (16) disposed such that light travels through the hole, a substrate (11) as a second substrate having a semiconductor device (26) for driving the optical semiconductor device (16) and amplifying signals and an electrical connector (28) for inputting and outputting electrical signals from and to the outside, and a flexible cable (12) electrically connecting an end of the substrate (10) and an end of the substrate (11) and allowing the first substrate to be folded opposite to the surface on which the optical semiconductor device is mounted.

Abstract: An electrode tip dresser is disclosed which can dress a pair of electrode tips to a usable state while achieving a desired accuracy of a tip surface of each electrode tip including an angular portion at a peripheral edge of the tip surface, without separating each electrode tip from a welding gun. The electrode tip dresser includes a holder which is rotatable about a common axis of electrode tips, a pair of support shafts which are held by the holder, are arranged in parallel in an approach direction of the electrode tips, and extend in a direction orthogonal to the approach direction, and a pair of dressing rollers which are rotatably supported by the support shafts, respectively, to dress the electrode tips to a usable state.

Abstract: A handheld optical unit is disclosed to measure optical characteristics of an optical input. A personal digital assistant is mounted to a housing to serve as a host computer for an optical spectrum analyzer disposed within the housing.