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US6234645B1 Expired / Lapsed US ⏱️ 0.0 years remaining

LED lighting system for producing white light

Assignee: Signify North America Corp
•
Filing: 1999-09-15
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Granted: 2001-05-22
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Expires: 2019-09-15
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Abstract

Abstract As a white light source, the lighting system (1) has at least three light-emitting diodes (6, 7, 8) for providing visible light at preselected wavelengths. The invention is characterized in that the lighting system (1) is provided with at least one fourth light-emitting diode (9) which, in operation, emits visible light in a further wavelength region, the maximum of the spectral emission of the fourth light-emitting diode (9) lying in the further wavelength region from 575 to 605 nm. Preferably, the further wavelength region ranges from 585 to 600 nm. Preferably, the color rendition of the lighting system (1) is above 60. Preferably, the luminous efficacy of the lighting system (1) is above 30 lm/W, preferably above 40 lm/W. In another preferred embodiment, the color temperature of the lighting system (1) can be adjusted by selectively switching the light-emitting diodes (6, 7, 8, 9).

Inventors

  • 👤 Herbert Friedrich Börner
  • 👤 Wolfgang Busselt
  • 👤 Thomas Jüstel
  • 👤 Hans Nikol
  • 👤 Cornelis R. Ronda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 12:43
CPC Classifications
F; F21; F21K; F21K9/00; F21K9/20; F21K9/23; F21K9/233; F21K9/60; F21K9/62; H; H10; H10W; H10W90/00; F21Y; F21Y2113/00; F21Y2113/10; F21Y2113/13; F21Y2115/00; F21Y2115/10; Y; Y10; Y10S; Y10S362/00; Y10S362/80

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 66 words
A lighting system for producing white light, which lighting system comprises four light-emitting diodes, each one of the light-emitting diodes emitting, in operation, visible light in a preselected wavelength range, one of the said light emitting diodes having a maximum of spectral emission lying in the wavelength range from 575 to 605 nm, wherein the luminous efficacy of the lighting system is greater than 40 lm/W.
Claim 2
Dependent Claim 66 words
A lighting system for producing white light, which lighting system comprises four light-emitting diodes, each one of the light-emitting diodes emitting, in operation, visible light in a preselected wavelength range, one of the said light emitting diodes having a maximum of spectral emission lying in the wavelength range from 575 to 605 nm, wherein the luminous efficacy of the lighting system is greater than 40 lm/W.
Claim 3
Dependent Claim 35 words
A lighting system as claimed in claim 1 , wherein the maximum of the spectral emission of said one of the said light emitting diodes lies in the wavelength range from 585 to 600 nm.
Claim 4
Dependent Claim 22 words
A lighting system as claimed in claim 1 , wherein a color rendering index of the lighting system is at least 60.
Claim 5
Dependent Claim 32 words
A lighting system as claimed in claim 1 , wherein the four light-emitting diodes comprise a blue light-emitting diode, a blue-green light-emitting diode, a red light-emitting diode, and a yellow light-emitting diode.
Claim 6
Dependent Claim 74 words
A lighting system as claimed in claim 4 , wherein the maximum of the spectral emission of the blue light-emitting diode lies in the wavelength range from 460 to 490 nm, the maximum of the spectral emission of the blue-green light-emitting diode lies in the wavelength range from 510 to 530 nm, and the maximum of the spectral emission of the red light-emitting diode lies in the wavelength range from 610 to 630 nm.
Claim 7
Dependent Claim 17 words
A lighting system as claimed in claim 1 , wherein the lighting system provided with reflection means.
Claim 8
Dependent Claim 31 words
A lighting system as claimed in claim 6 , wherein the reflection means comprise a material selected from the group formed by BaSO 4 , ZnS, ZnO and TiO 2 .
Claim 9
Dependent Claim 25 words
A lighting system as claimed in claim 1 , wherein the color temperature of the lighting system is adjustable by separately driving the light-emitting diodes.

References Cited (Backward Citations)

US5515136A Cited
US5001609A Cited
DE3916875A1 Cited
US5803579A Cited
US5851063A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2004-05-21 2004-11-20 2005-05-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2008-05-21 2008-11-20 2009-05-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2012-05-21 2012-11-20 2013-05-22 $7700.00 Window Closed / Lapsed

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