LED and phosphor combinations for high luminous efficacy lighting with superior color control
A light emitting device comprises a first group of one or more LEDs each configured to emit light having a blue color point in the 1931 CIE x,y Chromaticity Diagram, a second group of one or more LEDs each configured to emit light having a cyan or yellow color point in the 1931 CIE x,y Chromaticity Diagram, and a third group of one or more LEDs each configured to emit light having a red color point in the 1931 CIE x,y Chromaticity Diagram.
1. A light emitting device comprising:
a first group of one or more light emitting diodes (“LEDs”) each configured to emit light having a blue color point in a 1931 International Commission on Illuminations (“CIE”) x,y Chromaticity Diagram, the first group having an average 1931 CIE x,y color point of x blue , y blue with y blue ≤0.295;
a second group of one or more LEDs each configured to emit light having a cyan or yellow color point in the 1931 CIE x,y Chromaticity Diagram, the second group having an average 1931 CIE x,y color point of x yellow-cyan , y yellow-cyan ;
a third group of one or more LEDs each configured to emit light having a red color point in the 1931 CIE x,y Chromaticity Diagram, the third group having an average 1931 CIE x,y color point of X red , y red ;
the first group of LEDs, the second group of LEDs, and the third group of LEDs are arranged to combine light emitted by the LEDs to form a white light output from the light emitting device;
1.10
≤
(
x
blue
+
x
yellow
-
cyan
+
x
red
)
≤
1.40
;
1.05
≤
(
y
blue
+
y
yellow
-
cyan
+
y
red
)
≤
1.25
;
each of the LEDs in the first, second, and third groups has a color point for which the x value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.15; and
each of the LEDs in the first, second, and third groups has a color point for which the y value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.15.
2. The light emitting device of claim 1 , wherein:
1.15
≤
(
x
blue
+
x
yellow
-
cyan
+
x
red
)
≤
1.40
;
1.10
≤
(
y
blue
+
y
yellow
-
cyan
+
y
red
)
≤
1.25
;
each of the LEDs in the first, second, and third groups has a color point for which the x value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.2; and
each of the LEDs in the first, second, and third groups has a color point for which the y value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.2.
3. The light emitting device of claim 1 , wherein:
1.20
≤
(
x
blue
+
x
yellow
-
cyan
+
x
red
)
≤
1.32
;
1.10
≤
(
y
blue
+
y
yellow
-
cyan
+
y
red
)
≤
1.20
;
each of the LEDs in the first, second, and third groups has a color point for which the x value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.2; and
each of the LEDs in the first, second, and third groups has a color point for which the y value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.2.
4. The light emitting device of claim 1 , wherein the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram of 0.01<gamut area <0.07.
5. The light emitting device of claim 1 , wherein the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram 0.015<gamut area <0.055.
6. The light emitting device of claim 1 , wherein the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram of 0.02<gamut area <0.045.
7. The light emitting device of claim 1 , wherein the blue color point is desaturated.
8. The light emitting device of claim 7 , wherein the cyan or yellow color point is desaturated.
9. The light emitting device of claim 8 , wherein the red color point is desaturated.
10. The light emitting device of claim 1 , wherein all of the LEDs in the first group, the second group, and the third group are phosphor-converted LEDs comprising a semiconductor diode structure configured to emit blue light and one or more phosphors arranged to absorb blue light emitted by the semiconductor diode structure and in response emit light of longer wavelengths.
11. The light emitting device of claim 1 , wherein:
the LEDs of the first group each comprise a semiconductor diode structure configured to emit blue light and a first phosphor arranged to absorb blue light emitted by the semiconductor diode structure and in response emit light of a longer wavelength mixed with unabsorbed blue light, and no other phosphors;
the LEDs of the second group each comprise a semiconductor diode structure configured to emit blue light and a second phosphor arranged to absorb blue light emitted by the semiconductor diode structure and in response emit light of a longer wavelength, and no other phosphors; and
the LEDs of the third group each comprise a semiconductor diode structure configured to emit blue light, the first phosphor arranged to absorb blue light emitted by the semiconductor diode structure and in response emit light of a longer wavelength, and the second phosphor arranged to absorb blue light emitted by the semiconductor diode structure and in response emit light of a longer wavelength, and no other phosphors.
12. The light emitting device of claim 11 , wherein:
the first phosphor absorbs blue light and emits red light; and
the second phosphor absorbs blue light and emits cyan light.
13. The light emitting device of claim 1 , wherein:
the LEDs in the first group, the second group, and the third group are phosphor-converted LEDs comprising a semiconductor diode structure configured to emit blue light and one or more phosphors arranged to absorb blue light emitted by the semiconductor diode structure and in response emit light of longer wavelengths; and
the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram of 0.01<gamut area <0.07.
14. The light emitting device of claim 13 , wherein:
the LEDs of the first group each comprise a first phosphor arranged to absorb blue light and in response emit light of a longer wavelength mixed with unabsorbed blue light, and no other phosphors;
the LEDs of the second group each comprise a second phosphor arranged to absorb blue light and in response emit light of a longer wavelength, and no other phosphors; and
the LEDs of the third group each comprise the first phosphor arranged to absorb blue light emitted and in response emit light of a longer wavelength, and the second phosphor arranged to absorb blue light and in response emit light of a longer wavelength, and no other phosphors.
15. The light emitting device of claim 14 , wherein:
the first phosphor absorbs blue light and emits red light; and
the second phosphor absorbs blue light and emits cyan light.
16. A light emitting device comprising:
a first group of one or more light emitting diodes (“LEDs”) each configured to emit light having a blue color point in a 1931 International Commission on Illuminations (“CIE”) x,y Chromaticity Diagram, the first group having an average 1931 CIE x,y color point of x blue , y blue ;
a second group of one or more LEDs each configured to emit light having a cyan or yellow color point in the 1931 CIE x,y Chromaticity Diagram, the second group having an average 1931 CIE x,y color point of x yellow-cyan , y yellow-cyan with y yellow-cyan ≤0.492;
a third group of one or more LEDs each configured to emit light having a red color point in the 1931 CIE x,y Chromaticity Diagram, the third group having an average 1931 CIE x,y color point of x red , y red ;
the first group of LEDs, the second group of LEDs, and the third group of LEDs are arranged to combine light emitted by the LEDs to form a white light output from the light emitting device;
1.10
≤
(
x
blue
+
x
yellow
-
cyan
+
x
red
)
≤
1.40
;
1.05
≤
(
y
blue
+
y
yellow
-
cyan
+
y
red
)
≤
1.25
;
each of the LEDs in the first, second, and third groups has a color point for which the x value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.15; and
each of the LEDs in the first, second, and third groups has a color point for which the y value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.15.
17. The light emitting device of claim 1 , wherein:
1.20
≤
(
x
blue
+
x
yellow
-
cyan
+
x
red
)
≤
1.32
;
1.10
≤
(
y
blue
+
y
yellow
-
cyan
+
y
red
)
≤
1.20
;
each of the LEDs in the first, second, and third groups has a color point for which the x value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.2; and
each of the LEDs in the first, second, and third groups has a color point for which the y value in the 1931 CIE x,y Chromaticity Diagram is greater than 0.2.
18. The light emitting device of claim 1 , wherein the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram of 0.01<gamut area <0.07.
19. The light emitting device of claim 1 , wherein the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram 0.015<gamut area <0.055.
20. The light emitting device of claim 1 , wherein the color points (x blue , y blue ), (x yellow-cyan , y yellow-cyan ), and (x red , y red ) span an absolute gamut in the CIE 1931 x,y Chromaticity Diagram of 0.02<gamut area <0.045.