Patent ID: 7169002
Filing Date: 2007-01-30
Classification: H01J

Abstract:
1. A method of manufacturing a high-pressure discharge lamp, said high-pressure discharge lamp having a quartz glass tube made up of a spherical space and straight tube sections extending from both sides of said spherical space; a pair of tungsten electrodes disposed in said spherical space such that one end of one tungsten electrode opposes one end of one tungsten electrode; a molybdenum foil overlapping with and welded to the other end of each of said tungsten electrodes; and an external lead wire welded to an end of each said molybdenum foil opposite to said tungsten electrode, wherein an inert gas containing mercury and a halogen gas is enclosed in said spherical space, the other ends of said tungsten electrodes and said molybdenum foils are embedded in glass of said respective straight tube sections, and said spherical space is hermetically sealed, said method comprising the steps of: bringing a shaft of each said tungsten electrode into close contact with said molybdenum foil; radiating a laser light, having a metal melting wavelength, onto a junction of said molybdenum foil with the shaft of each said tungsten electrode, from a location closer to said molybdenum foil; and melting both said molybdenum foil and the shaft of each said tungsten electrode for welding.