Patent · US Active

Light emitting device having various color temperature

US7679281B2 · kind B2 · utility

138Cited by
2References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 19, 2008
Grant dateMar 16, 2010
Priority date
Expiry dateOct 31, 2028

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF21Y2115/10
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A light emitting device capable of emitting light having various color temperatures is disclosed. The light emitting device includes a first light emitting part emitting a daylight color having a color temperature of 6000 K or more, a second light emitting part emitting white light having a color temperature less than 6000 K, and a third light emitting part emitting light in a visible range of 580 nm or more. The second and third light emitting parts are operable independently of the first light emitting part, and realize a warm white color having a color temperature of 3000 K or less with the white light emitted from the second light emitting part and the light emitted from the third light emitting part. The light emitting device realizes white light of various spectra and color temperatures corresponding to desired mood and utility. The light emitting device is controlled to emit light having a suitable wavelength or a suitable color temperature depending on the circadian rhythm of human, thereby enabling improvement of the user's health.

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