Abstract: The invention relates to a current inlet conductor assembly particularly for vacuum devices, especially for light sources such as incandescent lamps or discharge tubes, comprising an inlet conductor made of molybdenum for passing electric current and being surrounded by a vitreous material forming a hermetic seal therewith and an intermediate metal coating covering the surface of the inlet conductor at least on the places to be welded. The essence of the invention is that the intermediate metal coating is made of rhenium, advantageously with a thickness from 3 to 1200 nm. As proposed, the intermediate rhenium layer should be produced by electrolytic deposition, especially from an aqueous solution.

Abstract: Electrical current supply terminal, especially for discharge tubes of light sources having a high pressure gas discharge.The invention is concerned with an electrical feed through, especially for discharge tubes of light sources having high pressure gas discharge, which current supply terminal is passed through a ceramic material, preferably from aluminum oxide and with a binding material is hermetically binded thereto, the heat expansion coefficient of which is appropriately selected and which is preferably vitreous enamel.In order to eliminate the difficulties resulting from the different heat expansion coefficient of ceramics, binding material and the metal material, the feed through is formed from a bundle of metallic threads.The bundle comprises preferably strands or braids and as material preferably molybdenum or tungsten is used.

Abstract: A tubular discharge vessel for high pressure sodium vapor lamps has a wall 1 made of light-transmitting material. The tube 1 is hermetically sealed at each end by a respective ceramic stopper 2 through which is passed a respective current lead-in wire 11. An electrode 8 is joined via a shank 10 to the current lead-in wire 11. The interior of the tube is filled with noble gas(es) and metal additive(s), e.g. sodium, mercury and/or cadmium. A cavity 9, preferably of rotationally symmetrical shape is formed in at least one of the stoppers 2. In operation of the discharge tube the cavity 9 is the cold spot. i.e. the internal wall of the lowest temperature. The volume of the cavity 9 is at least equal to the volume of the metal additives in their liquid phase.

Abstract: A high-pressure gas discharge light source with high light conversion efficiency and color rendering, having a translucent discharge vessel of high melting point material in which electrodes of high melting point material are suspended and containing a filling of an inert gas or a mixture of inert gases, at least one metal halide and optionally one or more metals in the elemental state under cold conditions, wherein the ratio of the metal to the halogen forming the halide is stoichiometric or greater, and the specific wall load factor is between 25 and 200 W/cm.sup.2 and/or the quantity of the halide or halides is 0.01 to 1 mg per centimeter length of the arc.