Abstract: A laser machining apparatus includes a laser beam source, such as of excimer laser, which produces a laser beam to be projected on a work piece or a sample, first and second illumination light sources which have wavelengths substantially equal to the wavelength of the laser beam and illuminate the entire image and the laser beam, respectively, a first beam splitter which guides the image produced by the illumination light to an observation unit, a second beam splitter which guides the laser beam from the laser beam source to an objective lens, and a controller which controls the machining condition including the relative positioning between the sample and the laser beam depending on the result of observation. The laser beam guide path structure from the laser beam source to the sample has its interior wall made of laser-transparent material such as glass, and the transparent material is enclosed by a laser blocking material such as a metal or water.

Abstract: A metal layer other than gold is formed on a ceramic substrate, a gold layer is further formed on said metal layer, and then a high density beam is applied to the treated substrate member. Thereby, the metal of the underlayer diffused through the grain boundaries of gold up to the surface of the gold layer by heat treatment or the like is uniformly mixed with gold to form an alloyed layer excellent in wettability to a solder. At the same time, nonmetallic impurities such as carbon adhering onto the surface of the gold layer are melted and removed.

Abstract: A pneumatic journal bearing suitable for application to a rotating shaft which will acquire high temperature during operation, such as the turbine shaft in an automotive turbocharger. In this journal bearing, the cylindrical hole of the bearing body has a diameter considerably larger than the diameter of the shaft rotating therein. A hollow cylindrical journal member having an inner diameter substantially larger than the diameter of the shaft is coaxially disposed in the bearing hole and coaxially fixed to the shaft at two end plates of the cylindrical journal member, and compressed air is introduced into a clearance space between the journal member and the cylindrical bearing surface. Since the cylindrical major portion of the journal member is spaced from the shaft, the journal member does not undergo such significant thermal expansion as results in significant narrowing of the clearance space even though the shaft acquires high temperature.