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. 10, 1990
Filed:
Jul. 24, 1989
Sharon B Rutfield, North Chelmsford, MA (US);
GTE Products Corporation, Danvers, MA (US);
Abstract
A fluorescent lamp suitable for backlighting a liquid crystal display includes a three-component phosphor disposed within the lamp envelope and responsive to the ultraviolet radiation generated by the plasma discharge in the lamp. The phosphor includes a first component having a first energy peak with a predetermined maximum intensity located within the wavelength range of from about 435 nanometers to 440 nanometers. A second component of the phosphor generates a second energy peak with a predetermined maximum intensity located within the wavelength range of from about 545 nanometers to 550 nanometers. A third component of the phosphor provides a third energy peak with a predetermined maximum intensity located within the wavelength range of from about 610 nanometers to 615 nanometers. The maximum intensity value of the first energy peak is within the range of from about 70% to 115% of the maximum intensity of the second energy peak. The maximum intensity value of the third energy peak is within the range of from about 65% to 87% of the maximum intensity of the second energy peak. The three energy peaks have bandwidths less than or equal to about 40 nanometers as measured at an intensity which is 50% of a respective maximum peak intensity. In one embodiment, the phosphor comprises a blend including about 42% to 44% by weight europium-activated strontium chlorophosphate, about 25% to 29% by weight cerium-terbium-activated magnesium aluminate and about 27% to 33% by weight europium-activated yttrium oxide.