| 摘要 |
<p>In a case of manufacturing a double ended discharge lamp, it is intended to decrease the manufacturing cost while maintaining identical lamp characteristic and lamp lifetime with those in a case of forming a quartz bulb with quartz at a high purity. In a quartz bulb (1) in which a pair of straight tube portions (2A, 2B) each having a sealing tube (4A, 4B) for sealing an electrode mount (M) and a supply/exhaust tube (5A, 5B) that is cut and removed after sealing in communication to each other are formed on both ends of a chamber (3) as a light emitting portion, end portions (1A, 1B) of the quartz tube including the entire portion or a portion of the supply/exhaust tubes (5A, 5B) are formed in contiguous with the central portion (1C) of the quartz tube including all portions forming the inner surface (3a) of the chamber, and one or both of the end portions (1A, 1B) of the quartz tube is formed of quartz at a purity lower than that of the central portion (1C) of the quartz tube.</p> |
