Semiconductor light emitting devices having selectable and/or adjustable color points and related methods
US9006986B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 2014 |
| Grant date | Apr 14, 2015 |
| Priority date | — |
| Expiry date | Jun 10, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/60
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Semiconductor light emitting devices are provided that include a first string of light emitting diodes (“LED”) that emit unsaturated light having a color point that is within at least eight MacAdam ellipses of one or more points within a first blue-shifted-yellow region on the 1931 CIE Chromaticity Diagram, a second string of LEDs that emit unsaturated light having color point that is within at least eight MacAdam ellipses from one or more points within a second blue-shifted-green region on the 1931 CIE Chromaticity Diagram, and a third light source that emits radiation having a dominant wavelength between 600 and 720 nm. A drive circuit is provided that is configured to supply a first drive current to the first string of LEDs, a second drive current to the second string of LEDs and a third drive current to the third string of LEDs, wherein at least two of the first, second and third drive currents are independently controllable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.