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. 09, 1982
Filed:
Dec. 31, 1979
Henry Skwirut, Verona, NJ (US);
Robert G Young, Nutley, NJ (US);
Westinghouse Electric Corp., Pittsburgh, PA (US);
Abstract
Fluorescent lamps have a predetermined correlated color temperature and a combined efficiency and good color rendition of illuminated objects. The lamps utilize a two-layer phosphor coating comprising a layer coated onto the envelope interior surface and formed of a very high performance three-component blend which includes a blue-emitting phosphor, a green-emitting manganese-activated zinc silicate phosphor, and a red-orange emitting phosphor, all mixed in predetermined amounts and relative proportions to provide an emission of approximate predetermined x-y coordinates. Under some conditions, the phosphor blend when used as a single layer is subject to depreciation of the light output of the green component, particularly in the vicinity of the lamp electrodes which results in color shifts which are objectionable from an aesthetic standpoint. To protect the green-emitting component of the high performance blend, there is provided over the phosphor blend layer a very thin layer of finely divided phosphor which is very stable and which has an emission of approximately the same x-y coordinates as the high performance phosphor blend layer. The resulting lamp has overall improved performance from an aesthetic standpoint.