Abstract: In manufacturing an optical semiconductor device, light-emitting elements are mounted on their respective printed boards of an insulating plate with a silver paste interposed therebetween. A sealing mold having a shape (a lens forming portion) necessary for forming a projected lens is adhered to the major surface of the insulating plate in accordance with each of the light-emitting elements of each of the printed boards. A liquid epoxy resin having a melt viscosity of 100 Pa.multidot.s to 200 Pa.multidot.s is continuously injected into the sealing mold with the lens forming portion of the sealing mold downward. The liquid epoxy resin is then hardened to form a projected, domed lens on each of the light-emitting elements. After that, the sealing mold is removed, and the insulating plate is separated for each of the light-emitting elements into surface-mounted optical semiconductor devices each having a projected, domed lens.

Abstract: A sampling device for a quantitative determination of hydrogen in molten metal, which includes a material in which hydrogen is relatively non-diffusible during testing or readily soluble during sampling and a refractory vessel housing this material. This refractory vessel is sealed so as to maintain a vacuum or negative (reduced) pressure therein, and is provided with a thin-walled aspirating portion which is readily destroyed by an external pressure.