Light-emitting device, vehicular lighting fixture comprising the device, and head lamp
US8274208B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 15, 2008 |
| Grant date | Sep 25, 2012 |
| Priority date | — |
| Expiry date | Nov 23, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/8512
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light-emitting device comprising a light source which emits excitation light and a fluorescent substance which absorbs the excitation light to emit light in combination, wherein a fluorescent substance comprising an α type SiAlON represented by the general formula: (Caα,Euβ)(Si,Al)12(O,N)16 (1.5<α+β<2.2, 0<β<0.2, O/N≦0.04) as a main component and having a specific surface area of 0.1 to 0.35 m2/g is used as the fluorescent substance. This light-emitting device shows little color change due to temperature change and efficiently emits light, even when it is used in a high temperature environment, and it is especially suitable for lighting apparatuses for vehicles such as headlamps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.