The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 18, 1995
Filed:
Mar. 04, 1994
Zsolt Marton, Budapest, HU;
Tungsram Co., Ltd., Budapest, HU;
Abstract
This invention relates to a high pressure sodium vapor discharge lamp the discharge space of which is enclosed by a ceramic vessel having hermetically sealed ceramic end members with electric lead wires connected with electrodes inside the discharge vessel and the discharge vessel contains sodium, noble gas, mercury in a concentration of 0-5 mg/cm.sup.3 and at least one further metal additive having a vapor pressure not exceeding 7.5 torr at 1000K temperature. The discharge lamp according to the invention is further characterized in that the molar fraction of sodium in the total metal additive exceeds 0.5 and the molar fraction of sodium is greater than four times the molar fraction of mercury.