Light emitting device and illumination device
US8053970B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 11, 2009 |
| Grant date | Nov 8, 2011 |
| Priority date | — |
| Expiry date | Mar 11, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An LED with a semiconductor light emitting element that emits a blue or a blue-violet light, and a fluorescent material that absorbs some or all of the light emitted from the element and emits a fluorescent light of a wavelength different from the absorbed light. The fluorescent material is a mixed fluorescent material obtained by mixing a first fluorescent material that emits a blue-green or a green light, a second fluorescent material that has a peak emission wavelength longer than that of the first fluorescent material and emits a green or a yellow-green light, a third fluorescent material that has a 1 peak emission wavelength longer than that of the second fluorescent material and emits a yellow-green, a yellow or a yellow-red light, and a fourth fluorescent material that has a peak emission wavelength longer than that of the third fluorescent material and emits a yellow-red or a red light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.