LED illumination device with layered phosphor pattern
US7740514B2 · kind B2 · utility
12Cited by
9References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 20, 2007 |
| Grant date | Jun 22, 2010 |
| Priority date | — |
| Expiry date | Jul 14, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/0361
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method of applying at least two phosphors to an LED, wherein a first phosphor material having a lower absorption, shorter luminescence decay time, and/or lower thermal quenching than a second phosphor material is positioned closer to the LED than the second phosphor. Such an arrangement provides a light emitting device with improved lumen output and color stability over a range of drive currents.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.