| 摘要 |
PURPOSE:To obtain good air-tightness and prevent metallic foil conductors from oxidation in a bulb made of quartz glass, by providing a film consisting of metal oxide on surface of external lead-in wires connected to the metallic foil conductors in sealed parts. CONSTITUTION:A bulb 1 is formed by quartz glass of high purity and enclosed from the outside by forming press-crushed sealed parts 2 at its both ends. A coil filament 3 made from tungsten is arranged along a tube axis of the bulb 1 and its both ends are connected through internal lead-in wires 5 to metallic foil conductors 6 sealed in sealed parts 2. The metallic foil conductor 6 is made, for instance, from molybdenum, and its both side edges are formed in thin blade shape. External lead-in wires 8 welded to said metallic foil conductors 6 are formed by tungsten or molybedenum or their alloy, and an oxidized film 9 of material constituting said lead-in wire is previously formed, covering their sealed range in the sealed part 2. |
