Abstract: A high-pressure sodium lamp in which the inner diameter of an arc envelope is largest at the midpoint between the ends thereof and the inner and outer diameters thereof in the vicinity of the ends at which are air-tightly fitted electrodes and their associated parts are reduced gradually relative to the inner diameter of the midpoint thereof. When the arc envelope is turned on, the following conditions are satisfied:T.sub.e .gtoreq.0.85 T.sub.c and1020.degree. C..ltoreq.T.sub.c .ltoreq.1200.degree. C.where T.sub.e is the wall temperature at the leading or inner tip of each of the electrodes andT.sub.c is the wall temperature at the midpoint of the arc envelope.

Abstract: The invention relates to lamps having a glass lamp vessel (1) and to a glass suitable therefor. The relevant glass is adequately resistant to attack by electrons, is resistant to atmospheric influences and is properly workable in a gas flame. This glass contains 44-60 mole % silicon oxide; 0-7.5 mole % boron oxide; 0-6 mole % zirconium oxide; 0-7.5 mole % aluminium oxide; 5-20 mole % calcium oxide; 12.5-25 mole % barium oxide; 0-15 mole % magnesium oxide; 0-10 mole % strontium oxide; 2-8 mole % sodium oxide. The sum of the alkaline earth metals is 25-42.5 mole %.No discoloration occurs in sodium vapor discharge lamps when the lamp vessel has been made of this glass.

Abstract: Low-pressure sodium vapor discharge lamp. The lamp comprises a cylindrical discharge tube and an outer bulb enveloping this tube. The outer bulb has a transparent layer which reflects infrared radiation.According to the invention the resistance per square of the infrared reflecting layer is approximately 5 ohm. A luminous efficacy of 100 lumen per watt can be obtained at a lamp power of 8 watts. The lamp is particularly suitable for security lighting.

Abstract: A source of visible light including an electrodeless lamp containing a mercury halide, iodine, and nitrogen. When the contents of the electrodeless lamp are excited by high frequency power, visible light is emitted.

Abstract: An electromagnetic discharge apparatus including an electrodeless lamp containing a fill material which emit light when subjected to a high frequency electric field. Power is coupled to the contents of the lamp by a coupling fixture having an outer conductor of conductive mesh and an inner conductor. The electrodeless lamp is mounted between two electrodes, one from the inner conductor and one from the outer conductor which terminate closely adjacent to opposite outer surfaces of the electrodeless lamp.

Abstract: A source of ultraviolet radiation including an electrodeless lamp containing a metal iodide or iodine. When the contents of the electrodeless lamp are excited by high frequency power, excited iodine atoms emit ultraviolet radiation.

Abstract: An electrodeless fluorescent light source including an electrodeless lamp containing a metal iodide or iodine. A fluorescing material is disposed between the electrodeless lamp and an outer envelope. When the contents of the electrodeless lamp are excited by high frequency power, excited iodine atoms emit ultraviolet radiation. The ultraviolet radiation impinges on the fluorescing material causing it to emit visible light. The fluorescing material may be a solid phosphor material on the outer surface of the electrodeless lamp, a solid phosphor material on the inner surface of the outer envelope, a gaseous phosphor material in the space between the electrodeless lamp and the outer envelope, or some combination thereof.

Abstract: A source of visible light including an electrodeless lamp containing a mercury halide. When the contents of the electrodeless lamp are excited by high frequency power, excited mercury (I) halide molecules emit visible light.

Abstract: A high-pressure sodium lamp in which the ends of an arc tube which is made of transparent single-crystal alumina and which contains sodium are sealed with feed-throughs each having an electrode extended from the inner end thereof.Each feed-through is directly sealed to the inner wall surface of each end of the arc tube. In addition, each feed-through is formed with an enlarged-diameter portion which is directly sealed to the inner wall surface at each end of the arc tube and a reduced-diameter portion which is spaced apart from the inner wall surface at each end of the arc tube.

Abstract: Apparatus is disclosed for uniform exposure of a plurality of objects such as semiconductor wafers to radiation utilizing sources of radiation of linear configuration. The apparatus includes a baffle assembly of particular construction and constitution situated between the linear sources and the region to be irradiated.