Lighting device and lighting fixture
US9055638B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 13, 2013 |
| Grant date | Jun 9, 2015 |
| Priority date | — |
| Expiry date | Jan 30, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B45/375
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The controller changes an applied time (ON-time) of a DC voltage while keeping an intermittent period in which the DC voltage is supplied intermittently constant, when adjusting an average value of currents to a predetermined reference value or more, and changes a stopped time (OFF-time) of the DC voltage together with the intermittent period while keeping the applied time constant, when adjusting the average value to a value less than the predetermined reference value. Therefore, the lighting device can reduce variation in emission color compared with the conventional lighting device adopting DC Dimming Method, and can reduce variation in amount of light compared with the case where ON-time is changed until the dimming level reaches a lower limit. As a result, the lighting device can modulate light even at a low dimming level while reducing variation in emission color and variation in amount of light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.