Warm white LED spectrum especially for retail applications

Patent metadata

Field	Value
Publication number	US-11215339-B2
Application number	US-201816610356-A
Country	US
Kind code	B2
Filing date	Apr 26, 2018
Priority date	May 2, 2017
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

The invention provides a lighting device (100) configured to provide lighting device light (101), the lighting device (100) comprising a solid state light source (10) configured to provide blue light (11) having a peak wavelength (λPWL) selected from the range of 430-455 nm, a first luminescent material (210) configured to convert part of the blue light (11) into first luminescent material light (211) and a second luminescent material (220) configured to convert part of one or more of the blue light (11) and the first luminescent material light (211) into second luminescent material light (221), wherein the solid state light source (10), the first luminescent material (210), and the second luminescent material (220) are selected to provide at a first setting of the lighting device (100) white lighting device light (101) having a CRI of at least 90, a R9 value of at least 70, and a R50 value of at maximum 465 nm, wherein the R50 value is defined as a first wavelength (λ50) in a spectral distribution of the white lighting device light (101) at the first setting, wherein the first wavelength (λ50) is a wavelength closest to the peak wavelength (λPWL) but at a longer wavelength than the peak wavelength (λPWL) of the blue light (11) where the peak intensity (I50) is 50% of the intensity (IPWL) at the peak wavelength (λPWL).

First claim

The invention claimed is:

1. A lighting device configured to provide lighting device light, the lighting device comprising a solid state light source configured to provide blue light having a peak wavelength selected from the range of 430-455 nm, a first luminescent material configured to convert part of the blue light into first luminescent material light and a second luminescent material configured to convert part of one or more of the blue light and the first luminescent material light into second luminescent material light, wherein the solid state light source, the first luminescent material, and the second luminescent material are selected to provide at a first setting of the lighting device white lighting device light having a CRI of at least 90, a gamut area index (GAI) of at least 100, a R 9 value of at least 70 and a R 50 value of at maximum 455 nm, wherein the R 50 value is defined as a first wavelength (λ 50 ) in a spectral distribution of the white lighting device light at the first setting, wherein the first wavelength (λ 50 ) is a wavelength closest to the peak wavelength (λ PWL ) but at a longer wavelength than the peak wavelength (λ PWL ) of the blue light where the peak intensity (I 50 ) is 50% of the intensity (I PWL ) at the peak wavelength (λ PWL ),
and wherein the first luminescent material light has an intensity in one or more of the green wavelength range and yellow wavelength range having a CIE u 1 ′, and the second luminescent material light has an intensity in one or more of the orange wavelength range and red wavelength range having a CIE u 2 ′, wherein the first luminescent material and the second luminescent material are selected to provide said first luminescent material light and said second luminescent material light defined by a maximum ratio of CIE u 1 ′ and CIE u 2 ′ being CIE u 2 ′=1.58*CIE u 1 ′+0.255, and a minimum ratio of CIE u 1 ′ and CIE u 2 ′ being CIE u 2 ′( 221 )=2.3*CIE u 1 ′+0.04.

2. The light emitting device according to claim 1 , wherein the blue light has a peak wavelength (λ PWL ) selected from the range of 435-445 nm.

3. The light emitting device according to claim 1 , configured to provide white lighting device light having a gamut area index (GAI) in the range of 101-120 at the first setting.

4. The light emitting device according to claim 1 , configured to provide white lighting device light at the first setting having an R 50 value of at maximum 450 nm.

5. The light emitting device according to claim 1 , configured to provide white lighting device light at the first setting having a CIE v′ of at least 0.005 below the black body locus (BBL), and having a CIE v′ of at maximum 0.025 below the black body locus (BBL).

6. The light emitting device according to claim 1 , configured to provide white lighting device light with −0.014≤D uv ≤−0.005 at the first setting.

7. The light emitting device according to claim 1 , wherein the first luminescent material has an intensity in one or more of the green wavelength range and yellow wavelength range and the CIE v′ value is in the range of 0.55-0.58, and the second luminescent material has an intensity in one or more of the orange wavelength range and red wavelength range and the CIE v′ value is in the range of 0.52-0.55.

8. The light emitting device according to claim 1 , configured to provide white lighting device light at the first setting having a correlated color temperature selected from the range of 2700-4000 K.

9. The light emitting device according to claim 1 , wherein the first luminescent material comprises M 3 A 5 O 12 :Ce 3+ , wherein M is selected from the group consisting of Sc, Y, Tb, Gd, and Lu, wherein A is selected from the group consisting of Al, Ga, Sc and In.

10. The light emitting device according to claim 1 , wherein the second luminescent material comprises MAlSiN 3 :Eu, wherein M comprises one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca), wherein the second luminescent material comprises different MAlSiN 3 :Eu compounds, with a first compound with M at least comprising Ca and a second compound with M at least comprising Sr.

11. The light emitting device according to claim 1 , wherein:
the solid state light source is configured to provide blue light having a peak wavelength (λ PWL ) selected from the range of 435-445 nm
the solid state light source has a LED die, wherein the lighting device comprises a light converter comprising said first luminescent material and said second luminescent material, and wherein the light converter is in physical contact with the LED die;
the first luminescent material comprises M 3 A 5 O 12 :Ce 3+ , wherein M is selected from the group consisting of Sc, Y, Tb, Gd, and Lu, wherein A is selected from the group consisting of Al, Ga, Sc and In;
the second luminescent material comprises MAlSiN 3 :Eu, wherein M comprises one or more elements selected from the group consisting of barium (Ba), strontium (Sr) and calcium (Ca), wherein the second luminescent material comprises different MAlSiN 3 :Eu compounds, with a first compound with M at least comprising Ca and a second compound with M at least comprising Sr; and
the light emitting device is configured to provide white lighting device light at the first setting having an R 50 value of at maximum 455 nm.

12. The light emitting device according to claim 1 , configured to provide white lighting device light having spectral distributions (Watt) in the range of 11-13% for the blue light, 40-47% for the first luminescent material light, and 30-48% for the second luminescent material light, at the first setting.

13. A lighting system comprising the light emitting device according to claim 1 and a control system configured to control the light emitting device.

14. Use of the light emitting device according to claim 1 in retail lighting.

Assignees

• Signify Holding Bv

Inventors

• Peeters Martinus Petrus Joseph
• Wegh Rene Theodorus

Classifications

• F21Y2115/10

  Light-emitting diodes [LED] · CPC title

• C09K11/77348

  Silicon Aluminium Nitrides or Silicon Aluminium Oxynitrides · CPC title

• H10H20/851 Primary

  Wavelength conversion means · CPC title

• C09K11/0883

  Arsenides; Nitrides; Phosphides · CPC title

• F21K9/64

  using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer · CPC title