Phosphor composition used for fluorescent lamp and fluorescent lamp using the same
US5049779A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1989 |
| Grant date | Sep 17, 1991 |
| Priority date | — |
| Expiry date | Apr 28, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/44
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.