Color mixing for solid state lighting using direct AC drives
US9844114B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 9, 2016 |
| Grant date | Dec 12, 2017 |
| Priority date | — |
| Expiry date | Dec 9, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Techniques are described to allow a low-cost light fixture to produce light with a relatively high color rendering index (CRI) across a range of color temperatures. A rectified AC voltage may be provided to multiple groups of light-emitting diodes (LEDs) having characteristics related to a range of color temperatures and a target CRI level. The multiple groups of LEDs may be controlled based on a received control signal, such that the combined groups of LEDs produce combined light having a produced color temperature within the range of color temperatures, and having a produced CRI level that is approximately the target CRI level. In some implementations, the received control signal is modified by a modification circuit, and the multiple groups of LEDs may be controlled based on the modified control signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.