Title:
HIGH-VOLTAGE SODIUM DISCHARGE LAMP
Document Type and Number:
Japanese Patent JPH0613033
Kind Code:
A
Abstract:
PURPOSE: To prevent any dissipation of Na caused by a direct reaction of the wall of a discharge tube with alumina by disposing Al in a position where a temperature reaches at least 1000K in the operating state of a lamp in the vicinity of the wall of the discharge tube. CONSTITUTION: A discharge space 3b of a discharge tube 3 is surrounded by an alumina ceramic wall 3a. At least Na as an ionizing enclosed component, noble gas and Al exist inside the tube 3. A main electrode 4 is housed inside the space 3b. Electric discharge is generated between the main electrodes in an operating state. The main electrodes are connected to respective current introducing members 40 or the like, each of which is introduced through the wall 3a and is air-tightly connected to a tube wall via a fusing ceramic connecting portion 9. An Al pellet 20 is fixed by fusing to a position where a temperature reaches at least 1000K in the operating state of a lamp on the wall 3a positioned between the main electrodes 4. Consequently, it is possible to prevent any dissipation of Na caused by a direct reaction of the wall of the tube 3 with alumina.
Inventors:
PETORUSU FURANSHISUKUSU YOZEFU
Application Number:
JP8463293A
Publication Date:
January 21, 1994
Filing Date:
April 12, 1993
Export Citation:
Assignee:
PHILIPS ELECTRONICS NV
International Classes:
H01J61/12; H01J61/82; (IPC1-7): H01J61/12
Attorney, Agent or Firm:
Akihide Sugimura (5 outside)
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