Method and apparatus for constant light output pulsed L.E.D. illumination
US7393119B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 2007 |
| Grant date | Jul 1, 2008 |
| Priority date | — |
| Expiry date | Feb 12, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/802
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An illumination source includes a plurality of LEDs, and an electrical circuit that selectively applies power from the DC voltage source to the LED units, wherein the illumination source is suitable for handheld portable operation. In some embodiments, the electrical circuit further includes a control circuit for driving the LEDs with electrical pulses at a frequency high enough that light produced has an appearance to a human user of being continuous rather than pulsed, the control circuit changing a pulse characteristic to adjust a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output. Some embodiments provide an illumination source including a housing including one or more LEDs; and a control circuit that selectively applies power from a source of electric power to the LEDs, thus controlling a light output color spectrum of the LEDs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.