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:
Jun. 06, 2000
Filed:
Jun. 16, 1998
Perry Neil Yocom, Princeton, NJ (US);
Diane Zaremba, Fairless Hills, PA (US);
Sarnoff Corporation, Princeton, NJ (US);
Abstract
Red and orange-red emitting long persistence phosphors based on strontium sulfide and activated with a divalent rare earth such as europium, can be made by heating in the presence of an ammonium halide, or a trivalent rare earth. Using ammonium halide as the flux, the red-emitting phosphor can be molded into a desired shape. Using ammonium halide and powdered alumina, the red-emitting phosphor can be made into a powder directly. Heating a rare earth activated (Eu) strontium sulfide in the presence of a trivalent rare earth salt in the presence of sulfur and a source of carbon, fine particle size red-emitting phosphor particles can be made.