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:
Sep. 17, 1991
Filed:
Apr. 28, 1989
Yuji Itsuki, Anan, JP;
Keiji Ichinomiya, Anan, JP;
Nichia Kagaku Kogyo K.K., Tokushima, JP;
Abstract
A phosphor composition and a lamp having a phosphor film formed of the composition. The composition contains red, green and blue luminescence components. The blue component emits blue light by the excitation of 253.7-nm ultraviolet light. It has a main luminescence peak wavelength of 460 to 510 nm, and a half width of the main peak of a luminescence spectrum of not less than 50 nm. The color coordinates of the luminescence spectrum of the blue component falls within a range of 0.15.ltoreq.x.ltoreq.0.30 and of 0.25.ltoreq.y.ltoreq.0.40 based on the CIE 1931 standard chromaticity diagram. The blue component has a spectral reflectance of not less 80% at 380 to 500 nm, assuming that a spectral reflectance of a smoked magnesium oxide film is 100%. The amount of the blue component, with respect to the total weight of the composition, is specified within a region enclosed with solid lines (inclusive) connecting coordinate points a (5%, 2,500 K), b (5% 3,500 K), c (45% 8,000 K) d (95% 8,000 K), e (95% 7,000 K) and f (65%, 4,000 K) shown in FIG. 1 which are determined in accordance with a color temperature of the luminescence spectrum of the phosphor composition.