An optical connection structure which permits easy and automatic alignment between the optical axes of optical fibers and the optical axes of cores of an optical waveguide, and a production method which ensures that an optical waveguide for the optical connection structure can be efficiently produced with higher dimensional accuracy are provided. Such devices can be secured to circuit boards in a variety of ways, and to elastically deformed terminals. An equalization valve connects the two pressure lines. In one embodiment, a generate borrow instruction is similarly provided for an efficient implementation of multiprecision subtraction operations executed on the microprocessor. The clamp comprises a lid overreaching the top part in closed position and connected to the underpart by a closure, with which lid the entry opening is closable. The thermosetting sheet may comprise a substrate paper sheet and a thermosetting resin impregnated in the sheet.