Title:
HIGH VOLTAGE SODIUM VAPOR DISCHARGE LAMP
Document Type and Number:
Japanese Patent JPS5485576
Kind Code:
A
Abstract:
A high-pressure sodium vapor discharge lamp contains an electron-emitting material consisting of alkaline earth metals bound to oxygen and tungsten bound to oxygen. It has been found that such lamps of less than 400 W which have either a high Hg/Na ratio or use neon/argon as a starter gas fail prematurely when the alkaline earth metals and tungsten in the electron-emitting material are present in stoichiometric quantities. The free ends of electrodes of lamps according to the invention are wound with tungsten wire. Electron-emitting material comprising carium, strontium and calcium bound to oxygen and tungsten bound to oxygen is disposed in the cavities formed between the tungsten wire turns. The molar ration of the total barium, strontium and calcium bound to oxygen to the tungsten bound to oxygen is between 8 and 50.
Inventors:
KORUNERISU ADORIANUSU YOANESU
BEETERU ANDOREASU BARUSERUSU T
BEETERU ANDOREASU BARUSERUSU T
Application Number:
JP14800478A
Publication Date:
July 07, 1979
Filing Date:
December 01, 1978
Export Citation:
Assignee:
PHILIPS NV
International Classes:
H01J1/14; H01J61/073; H01J61/06; (IPC1-7): H01J61/06; H01J61/88
Domestic Patent References:
| JPS4935579B1 | 1974-09-24 | |||
| JPS5085181A | 1975-07-09 | |||
| JPS5124085A | 1976-02-26 | |||
| JPS5186280A | 1976-07-28 |
Foreign References:
| US3708710A | 1973-01-02 |