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:
Apr. 18, 2000
Filed:
Feb. 03, 1997
Jakob Schlejen, Morgantown, WV (US);
Johannes J Buck, Eindhoven, NL;
Christianus J Roozekrans, Eindhoven, NL;
U.S. Philips Corporation, New York, NY (US);
Abstract
An electrodeless low-pressure mercury vapor discharge lamp includes a discharge vessel that gas-tightly encloses a discharge-space that is provided with a fill of mercury and a noble gas. The discharge vessel has a light-transmitting enveloping part and further has a sunken part in which a coil for generating a high-frequency magnetic field is arranged. At least a portion of a surface of the discharge vessel turned towards the discharge space is provided with a luminescent layer. At least a portion of the luminescent layer bears a protective layer of aluminum oxide particles with a covering weight of 10 to 500 .mu.g/cm.sup.2. The protective layer provides for a lower mercury consumption and/or a reduction in the change of colour point during lamp life.