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:
Feb. 24, 1981
Filed:
Jan. 25, 1979
Antonius J Driessen, Eindhoven, NL;
Cornelis A Jacobs, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
The invention relates to a high-pressure sodium-vapor discharge lamp having substantially the same color temperature as an incandescent lamp. The invention provides a high-pressure sodium-vapor discharge lamp having a low re-ignition voltage. This is achieved by including xenon and mercury in the discharge tube such that (i) the weight of mercury is between 50% and 90% of the combined weight of the mercury and sodium, (ii) the pressure of the xenon at room temperature is between 100 and 1000 torr, and (iii) the sodium vapor pressure is between 300 and 800 torr in the operating condition of the lamp. The power consumed by such a lamp is typically one-fifth of that consumed by an incandescent lamp having the same light output.