| 摘要 |
PROBLEM TO BE SOLVED: To obtain an elongated straight-type discharge lamp light-emitting tube of which the lifetime is prolonged by preventing occurrence of leak even if a discharge arc (back arc) in a rear part of an electrode that is generated in initial lamp lighting is brought into contact with an end portion of the light-emitting tube.SOLUTION: A method of manufacturing a straight-type discharge lamp light-emitting tube is provided for obtaining a straight-type discharge lamp light-emitting tube 10 by welding, to both end portions of a cylindrical body pipe 12 comprised of a quartz glass pipe, end pipes 13 of which the diameter is smaller than that of the body pipe 12 and which is comprised of quartz glass. The method is characterized in that a diameter of an end portion of the end pipe 13 is expanded to form a cup-shaped large-diameter part 13a in one end of the end pipe 13 and the large-diameter part 13a is welded to the end portion of the body pipe 12. It is preferable that a difference between a thickness in the large-diameter part 13a of the end pipe 13 and a thickness of the body pipe 12 is less than or equal to 10% of the thickness of the body tube 12. |
