Patent · US Active

Semiconductor light emitting devices having selectable and/or adjustable color points and related methods

US8791642B2 · kind B2 · utility

44Cited by
17References
29Claims
0Family size

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Inventors

Key dates

Filing dateJul 11, 2012
Grant dateJul 29, 2014
Priority date
Expiry dateOct 5, 2032

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B45/60
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

Light emitting devices include a first string of LEDs that emit light having a color point that is within at least eight MacAdam ellipses of a first blue-shifted-yellow region on the 1931 CIE Chromaticity Diagram, a second string of LEDs that emit light having color point that is within at least eight MacAdam ellipses of 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 supplies respective drive currents to the first string of LEDs, the second string of LEDs and the third light source, at least two of which are independently controllable.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.