Lighting system for controlling the color temperature of artificial light under the influence of the daylight level
US5861717A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 1997 |
| Grant date | Jan 19, 1999 |
| Priority date | — |
| Expiry date | Aug 15, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B47/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lighting system having at least one light source for supplying artificial light and a control unit for controlling the light source. The light source is of the type having an adjustable color temperature. The control unit is provided with a control signal form a signal from a signal generator. The signal generator is dependent on the mean daylight level. The control unit is arranged to adjust the color temperature of the light source in dependence on a predetermined relationship between the mean daylight level and the color temperature of the artificial light. The lighting system will provide artificial light which will when the daylight level, as measured on an office desk, increases from approximately 400 lux to approximately 800 lux, increase the color temperature from approximately 3300 K to approximately 4300 K.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.