U.S. patent application number 16/895925 was filed with the patent office on 2020-09-24 for compositions for led light conversions.
This patent application is currently assigned to Ecosense Lighting Inc.. The applicant listed for this patent is Ecosense Lighting Inc.. Invention is credited to Raghuram L.V. Petluri, Paul Kenneth Pickard.
Application Number | 20200300423 16/895925 |
Document ID | / |
Family ID | 1000004874119 |
Filed Date | 2020-09-24 |
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United States Patent
Application |
20200300423 |
Kind Code |
A1 |
Petluri; Raghuram L.V. ; et
al. |
September 24, 2020 |
Compositions for LED Light Conversions
Abstract
Systems and methods to provide multiple channels of light to
form a blended white light output, the systems and methods
utilizing recipient luminophoric mediums to alter light provided by
light emitting diodes. The predetermined blends of luminescent
materials within the luminophoric mediums provide predetermined
spectral power distributions in the white light output.
Inventors: |
Petluri; Raghuram L.V.; (Los
Angeles, CA) ; Pickard; Paul Kenneth; (Los Angeles,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Ecosense Lighting Inc. |
Los Angeles |
CA |
US |
|
|
Assignee: |
Ecosense Lighting Inc.
Los Angeles
CA
|
Family ID: |
1000004874119 |
Appl. No.: |
16/895925 |
Filed: |
June 8, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16048685 |
Jul 30, 2018 |
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16895925 |
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PCT/US16/15318 |
Jan 28, 2016 |
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16048685 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F21V 5/04 20130101; C09K
11/0883 20130101; C09K 11/02 20130101; F21V 7/00 20130101; C09K
11/646 20130101; Y02B 20/00 20130101; C09K 11/7706 20130101; F21K
9/64 20160801; F21Y 2101/00 20130101; F21V 9/30 20180201; C09K
11/7734 20130101; F21V 3/00 20130101; G02B 6/0001 20130101; F21Y
2113/13 20160801; F21Y 2115/10 20160801; C09K 11/7721 20130101;
F21Y 2103/10 20160801 |
International
Class: |
F21K 9/64 20060101
F21K009/64; F21V 9/30 20060101 F21V009/30; C09K 11/77 20060101
C09K011/77; F21V 3/00 20060101 F21V003/00; F21V 5/04 20060101
F21V005/04; F21V 7/00 20060101 F21V007/00; F21V 8/00 20060101
F21V008/00; C09K 11/02 20060101 C09K011/02; C09K 11/08 20060101
C09K011/08; C09K 11/64 20060101 C09K011/64 |
Claims
1. A method of generating white light, the method comprising
passing light from a first LED string through a first luminophoric
medium comprised of one or more luminescent materials and matrix in
a first ratio for a first combined light in a blue color range on
1931 CIE diagram; passing light from a second LED string through a
second luminophoric medium comprised of one or more luminescent
materials and matrix in a second ratio for a second combined light
in a red color range on 1931 CIE diagram, wherein a spectral power
distribution for the second combined light in the red color range
is 100% for wavelengths between 621 nm to 660 nm and between 1.8%
to 74.3% for wavelengths between 661 nm to 700 nm, passing light
from a third LED string through a third luminophoric medium
comprised of one or more luminescent materials and matrix in a
third ratio for a third combined light in a yellow/green color
range on 1931 CIE diagram; passing light from a fourth LED string
through a fourth luminophoric medium comprised of one or more
luminescent materials and matrix in a fourth ratio for a fourth
combined light in a cyan color range on 1931 CIE diagram; and,
mixing the first, second, third, and fourth combined light
together; wherein the luminescent materials within each of the
first, second, third, and fourth luminophoric mediums comprise one
or more of a first type of luminescent material that emits light at
a peak emission between about 515 nm and 590 nm in response to the
associated LED string emission, and one or more of a second type of
luminescent material that emits light at a peak emission between
about 590 nm and about 700 nm in response to the associated LED
string emission, the one or more of the first type of luminescent
materials comprise BaMgAl.sub.10O.sub.17:Eu,
Lu.sub.3Al.sub.5O.sub.12:Ce, (La,Y).sub.3Si.sub.6N.sub.11:Ce, or
Y.sub.3Al.sub.5O.sub.12:Ce, and the one or more of the second type
of luminescent materials comprise CaAlSiN.sub.3:Eu,
(Sr,Ca)AlSiN.sub.3, or a semiconductor quantum dot.
2. The method of claim 1, wherein the blue color range comprises
one of regions 301A, 301B, or 301C, wherein 301A is a first region
defined by a line connecting an infinity point of a Planckian
locus, the Planckian locus from 4000K and infinite CCT, and a
constant CCT line of 4000 k, a line of purples, and a spectral
locus, 301B is a second region defined by a 60-step MacAdam ellipse
at a 20,000K CCT located 40 points below the Planckian locus, 301C
is a third region defined by a quadrilateral with a center point
located at (0.25, 0.20), the red color range comprises one of
regions 302A, 302B, or 302C, wherein 302A is a fourth region
defined by the spectral locus between a constant CCT line of 1600K
and the line of purples, the line of purples, a line connecting a
pair of color coordinates located at (0.61, 0.21) and (0.47, 0.28),
and the constant CCT line of 1600K, 302B is a fifth region defined
by a 20-step MacAdam ellipse at a 1200K CCT located 20 points below
the Planckian locus, and 302C is a sixth region defined by a
quadrilateral with a center point located at (0.58, 0.35), the
yellow/green color range comprises one of regions 303A, 303B, or
303C, wherein 303A is a seventh region defined by a constant CCT
line of 4600K, the Planckian locus between 4600K and 550K, the
spectral locus, and a line connecting a pair of color coordinates
located at (0.445, 0.555) and (0.38, 0.505), 303B is an eight
region defined by a 16-step MacAdam ellipse at a 3700 CCT located
30 points above the Planckian locus, and 303C is a ninth region
defined by a quadrilateral with a center point located at (0.45,
0.475), and the cyan color range comprises one of regions 304A,
304B, or 304C, wherein 304A is a tenth region defined by a line
connecting a pair of color coordinates located at (0.18, 0.55) and
(0.27, 0.72), a constant CCT line of 9000K, the Planckian locus
between 9000K and 4600K, a constant CCT line of 4600K, and the
spectral locus, 304B is an eleventh region defined by a 30-step
MacAdam ellipse at a 6000K CCT located 68 points above the
Planckian locus, and 304C is a twelfth region defined by a
quadrilateral with a center point located at (0.35, 0.52).
3. The method of claim 1, wherein the first luminophoric medium
comprises about 80% to about 99% by volume of the matrix.
4. The method of claim 1, wherein the first luminophoric medium
comprises about 93% to about 99% by volume of the matrix.
5. The method of claim 1, wherein the second luminophoric medium
comprises about 45% to about 90% by volume of the matrix.
6. The method of claim 1, wherein the third luminophoric medium
comprises about 1% to about 90% by volume of the matrix.
7. The method of claim 1, wherein the third luminophoric medium
comprises about 9% to about 90% by volume of the matrix.
8. The method of claim 1, wherein the fourth luminophoric medium
comprises about 54% to about 97% by volume of the matrix.
9. The method of claim 1, wherein the fourth luminophoric medium
comprises about 87% to about 97% by volume of the matrix.
10. The method of claim 1, wherein the third luminophoric medium
comprises up to about 99% by volume of
Lu.sub.3Al.sub.5O.sub.12:Ce.
11. The method of claim 1, wherein the fourth luminophoric medium
comprises up to about 30% by volume of
Lu.sub.3Al.sub.5O.sub.12:Ce.
12. The method of claim 1, wherein the first luminophoric medium
comprises up to about 7.5% by volume of
BaMgAl.sub.10O.sub.17:Eu.
13. The method of claim 1, wherein the second luminophoric medium
comprises up to about 15% by volume of
BaMgAl.sub.10O.sub.17:Eu.
14. The method of claim 1, wherein the third luminophoric medium
comprises up to about 85% by volume of
BaMgAl.sub.10O.sub.17:Eu.
15. The method of claim 1, wherein the fourth luminophoric medium
comprises up to about 10% by volume of
BaMgAl.sub.10O.sub.17:Eu.
16. The method of claim 1, wherein the first luminophoric medium
comprises up to about 5% by volume of CaAlSiN.sub.3.
17. The method of claim 1, wherein the second luminophoric medium
comprises up to about 55% by volume of CaAlSiN.sub.3.
18. The method of claim 1, wherein the spectral power distribution
of the first combined light has a spectral power distribution
intensity of between 0.3 and 8.1 for the wavelength range of
380-420 nm, between 20.9 and 196.1 for the wavelength range of
461-500 nm, between 15.2 and 35.6 for the wavelength range of
501-540 nm, between 25.3 and 40.5 for the wavelength range of
541-580 nm, between 26.3 and 70 for the wavelength range of 581-620
nm, between 15.4 and 80.2 for the wavelength range of 621-660 nm,
between 5.9 and 20.4 for the wavelength range of 661-700 nm,
between 2.3 and 7.8 for the wavelength range of 701-740 nm, and
between 1.0 and 2.3 for the wavelength range of 741-780 nm,
relative to a value of 100.0 for the wavelength range of 421-460
nm, wherein a spectral power distribution for the second combined
light in the red color range is between 0.0% to 14.8% for
wavelengths between 380 nm to 420 nm, between 2.1% to 15% for
wavelengths between 421 nm to 460 nm, between 2.0% to 6.7% for
wavelengths between 461 nm to 500 nm, between 1.4% to 12.2% for
wavelengths between 501 nm to 540 nm, between 8.7% to 20.5% for
wavelengths between 541 nm to 580 nm, between 48.5% and 102.8% for
wavelengths between 581 nm to 620 nm, 100% for wavelengths between
621 nm to 660 nm, between 1.8% to 74.3% for wavelengths between 661
nm to 700 nm, between 0.5% to 29.5% for wavelengths between 701 nm
to 740 nm, and between 0.3% to 9.0% for wavelengths between 741 nm
to 780 nm; wherein the spectral power distribution of the third
combined light has a spectral power distribution intensity of
between 0.0 and 1.1 for the wavelength range of 380-420 nm, between
1.0 and 25.3 for the wavelength range of 421-460 nm, between 4.2
and 52.7 for the wavelength range of 461-500 nm, between 56.6 and
77.5 for the wavelength range of 501-540 nm, between 80.5 and 123.4
for the wavelength range of 581-620 nm, between 48.4 and 144.9 for
the wavelength range of 621-660 nm, between 12.6 and 88.8 for the
wavelength range of 661-700 nm, between 3.2 and 34.4 for the
wavelength range of 701-740 nm, and between 1.0 and 10.5 for the
wavelength range of 741-780 nm, relative to a value of 100.0 for
the wavelength range of 541-580 nm, and wherein the spectral power
distribution of the fourth combined light has a spectral power
distribution of between 0.1 and 0.7 for the wavelength range of
380-420 nm, between 0.5 and 1.6 for the wavelength range of 421-460
nm, between 39.6 and 58.6 for the wavelength range of 461-500 nm,
between 62.0 and 80.4 for the wavelength range of 541-580 nm,
between 41.6 and 59.9 for the wavelength range of 581-620 nm,
between 23.1 and 57.1 for the wavelength range of 621-660 nm,
between 6.6 and 35.0 for the wavelength range of 661-700 nm,
between 1.8 and 13.5 for the wavelength range of 701-740 nm,
between 0.6 and 4.1 for the wavelength range of 741-780 nm,
relative to a value of 100.0 for the wavelength range of 501-540
nm.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 16/048,685 filed Jul. 30, 2018, which is a
continuation of International Patent Application no.
PCT/US2016/015318 filed Jan. 28, 2016, the contents of which are
incorporated by reference as if fully set forth herein.
FIELD
[0002] This disclosure is in the field of solid-state lighting. In
particular, the disclosure relates to luminophoric compositions for
use in methods of generating white light.
BACKGROUND
[0003] A wide variety of light emitting devices are known in the
art including, for example, incandescent light bulbs, fluorescent
lights, and semiconductor light emitting devices such as light
emitting diodes ("LEDs").
[0004] There are a variety of resources utilized to describe the
light produced from a light emitting device, one commonly used
resource is 1931 CIE (Commission Internationale de l'Eclairage)
Chromaticity Diagram. The 1931 CIE Chromaticity Diagram maps out
the human color perception in terms of two CIE parameters x and y.
The spectral colors are distributed around the edge of the outlined
space, which includes all of the hues perceived by the human eye.
The boundary line represents maximum saturation for the spectral
colors, and the interior portion represents less saturated colors
including white light. The diagram also depicts the Planckian
locus, also referred to as the black body locus (BBL), with
correlated color temperatures, which represents the chromaticity
coordinates (i.e., color points) that correspond to radiation from
a black-body at different temperatures. Illuminants that produce
light on or near the BBL can thus be described in terms of their
correlated color temperatures (CCT). These illuminants yield
pleasing "white light" to human observers, with general
illumination typically utilizing CCT values between 1,800K and
10,000K.
[0005] Color rendering index (CRI) is described as an indication of
the vibrancy of the color of light being produced by a light
source. In practical terms, the CRI is a relative measure of the
shift in surface color of an object when lit by a particular lamp
as compared to a reference light source, typically either a
black-body radiator or the daylight spectrum. The higher the CRI
value for a particular light source, the better that the light
source renders the colors of various objects it is used to
illuminate.
[0006] LEDs have the potential to exhibit very high power
efficiencies relative to conventional incandescent or fluorescent
lights. Most LEDs are substantially monochromatic light sources
that appear to emit light having a single color. Thus, the spectral
power distribution of the light emitted by most LEDs is tightly
centered about a "peak" wavelength, which is the single wavelength
where the spectral power distribution or "emission spectrum" of the
LED reaches its maximum as detected by a photo-detector. LEDs
typically have a full-width half-maximum wavelength range of about
10 nm to 30 nm, comparatively narrow with respect to the broad
range of visible light to the human eye, which ranges from
approximately from 380 nm to 800 nm.
[0007] In order to use LEDs to generate white light, LED lamps have
been provided that include two or more LEDs that each emit a light
of a different color. The different colors combine to produce a
desired intensity and/or color of white light. For example, by
simultaneously energizing red, green and blue LEDs, the resulting
combined light may appear white, or nearly white, depending on, for
example, the relative intensities, peak wavelengths and spectral
power distributions of the source red, green and blue LEDs. The
aggregate emissions from red, green, and blue LEDs typically
provide poor CRI for general illumination applications due to the
gaps in the spectral power distribution in regions remote from the
peak wavelengths of the LEDs.
[0008] White light may also be produced by utilizing one or more
luminescent materials such as phosphors to convert some of the
light emitted by one or more LEDs to light of one or more other
colors. The combination of the light emitted by the LEDs that is
not converted by the luminescent material(s) and the light of other
colors that are emitted by the luminescent material(s) may produce
a white or near-white light.
[0009] LED lamps have been provided that can emit white light with
different CCT values within a range. Such lamps utilize two or more
LEDs, with or without luminescent materials, with respective drive
currents that are increased or decreased to increase or decrease
the amount of light emitted by each LED. By controllably altering
the power to the various LEDs in the lamp, the overall light
emitted can be tuned to different CCT values. The range of CCT
values that can be provided with adequate CRI values and efficiency
is limited by the selection of LEDs.
[0010] The spectral profiles of light emitted by white artificial
lighting can impact circadian physiology, alertness, and cognitive
performance levels. Bright artificial light can be used in a number
of therapeutic applications, such as in the treatment of seasonal
affective disorder (SAD), certain sleep problems, depression, jet
lag, sleep disturbances in those with Parkinson's disease, the
health consequences associated with shift work, and the resetting
of the human circadian clock. Artificial lighting may change
natural processes, interfere with melatonin production, or disrupt
the circadian rhythm. Blue light may have a greater tendency than
other colored light to affect living organisms through the
disruption of their biological processes which can rely upon
natural cycles of daylight and darkness. Consequently, exposure to
blue light late in the evening and at night may be detrimental to
one's health.
[0011] Significant challenges remain in providing LED lamps that
can provide white light across a range of CCT values while
simultaneously achieving high efficiencies, high luminous flux,
good color rendering, and acceptable color stability. It is also a
challenge to provide lighting apparatuses that can provide
desirable lighting performance while allowing for the control of
circadian energy performance.
[0012] It is therefore a desideratum to provide compositions for
converting light generated by LEDs into white light with desirable
spectral characteristics.
DISCLOSURE
[0013] Disclosed herein are aspects of compositions for use in
generating white light, the compositions comprising a plurality of
luminescent materials and a matrix material formed in a volumetric
ratio. The plurality of luminescent materials can comprise one or
more of a first type of luminescent material that emits light at a
peak emission between about 515 nm and 590 nm in response to the
associated LED string emission, and one or more of a second type of
luminescent material that emits light at a peak emission between
about 590 nm and about 700 nm in response to the associated LED
string emission. In some implementations, the one or more of the
first type of luminescent materials comprise BaMgAl10O17:Eu,
Lu3Al5O12:Ce, (La,Y)3Si6N11:Ce, or Y3Al5O12:Ce. In some
implementations, the one or more of the second type of luminescent
materials comprise CaAlSiN3:Eu, (Sr,Ca)AlSiN3, or one or more
semiconductor quantum dots. In some implementations the
compositions are configured to be excited by LEDs that emit
substantially saturated light at wavelengths between about 360 nm
and about 535 nm to produce light having color points within the
suitable blue color ranges 301A-C, red color ranges 302A-C,
yellow/green color ranges 303A-C, and cyan color ranges 304A-C
disclosed herein. In some instances the compositions are configured
so that the light emitted by the LED(s) and associated compositions
together have spectral power distributions ("SPD") having spectral
power with ratios of power across the visible wavelength spectrum
that fall within the ranges disclosed herein in FIGS. 7 and 8.
[0014] Disclosed herein are aspects of methods of generating white
light, the methods comprising passing light from a first LED string
through a first luminophoric medium comprised of one or more
luminescent materials and matrix in a first ratio for a first
combined light in a blue color range on 1931 CIE diagram, passing
light from a second LED string through a second luminophoric medium
comprised of one or more luminescent materials and matrix in a
second ratio for a second combined light in a red color range on
1931 CIE diagram, passing light from a third LED string through a
third luminophoric medium comprised of one or more luminescent
materials and matrix in a third ratio for a third combined light in
a yellow/green color range on 1931 CIE diagram, passing light from
a fourth LED string through a fourth luminophoric medium comprised
of one or more luminescent materials and matrix in a fourth ratio
for a fourth combined light in a cyan color range on 1931 CIE
diagram, and mixing the first, second, third, and fourth combined
light together. In some implementations the blue color range
comprises one of regions 301A, 301B, or 301C, the red color range
comprises one of regions 302A, 302B, or 302C, the yellow/green
color range comprises one of regions 303A, 303B, or 303C, and the
cyan color range comprises one of regions 304A, 304B, or 304C. In
some instances, the first, second, third, and fourth combined
lights can have spectral power distributions ("SPD") having
spectral power with ratios of power across the visible wavelength
spectrum that fall within the ranges disclosed herein in FIGS. 7
and 8. In some implementations of the methods, the luminescent
materials within each of the first, second, third, and fourth
luminophoric mediums comprise one or more of a first type of
luminescent material that emits light at a peak emission between
about 515 nm and 590 nm in response to the associated LED string
emission, and one or more of a second type of luminescent material
that emits light at a peak emission between about 590 nm and about
700 nm in response to the associated LED string emission. In some
implementations, the one or more of the first type of luminescent
materials can comprise BaMgAl1O017:Eu, Lu3Al5O12:Ce,
(La,Y)3Si6N11:Ce, or Y3Al5O12:Ce and the one or more of the second
type of luminescent materials can comprise CaAlSiN3:Eu,
(Sr,Ca)AlSiN3, or a semiconductor quantum dot.
[0015] The general disclosure and the following further disclosure
are exemplary and explanatory only and are not restrictive of the
disclosure, as defined in the appended claims. Other aspects of the
present disclosure will be apparent to those skilled in the art in
view of the details as provided herein. In the figures, like
reference numerals designate corresponding parts throughout the
different views. All callouts and annotations are hereby
incorporated by this reference as if fully set forth herein.
DRAWINGS
[0016] The disclosure, as well as the following further disclosure,
is best understood when read in conjunction with the appended
drawings. For the purpose of illustrating the disclosure, there are
shown in the drawings exemplary implementations of the disclosure;
however, the disclosure is not limited to the specific methods,
compositions, and devices disclosed. In addition, the drawings are
not necessarily drawn to scale. In the drawings:
[0017] FIG. 1 illustrates aspects of light emitting devices
according to the present disclosure;
[0018] FIG. 2 illustrates aspects of light emitting devices
according to the present disclosure;
[0019] FIG. 3 depicts a graph of a 1931 CIE Chromaticity Diagram
illustrating the location of the Planckian locus;
[0020] FIGS. 4A-4D illustrate some aspects of light emitting
devices according to the present disclosure, including some
suitable color ranges for light generated by components of the
devices;
[0021] FIG. 5 illustrates some aspects of light emitting devices
according to the present disclosure, including some suitable color
ranges for light generated by components of the devices;
[0022] FIG. 6 illustrates some aspects of light emitting devices
according to the present disclosure, including some suitable color
ranges for light generated by components of the devices;
[0023] FIGS. 7-8 are tables of data of relative spectral power
versus wavelength regions for some suitable color points of light
generated by components of devices of the present disclosure;
and
[0024] FIG. 9 is a table of data of light output of light emitting
diodes suitable for implementations of the present disclosure.
[0025] The general disclosure and the following further disclosure
are exemplary and explanatory only and are not restrictive of the
disclosure, as defined in the appended claims. Other aspects of the
present disclosure will be apparent to those skilled in the art in
view of the details as provided herein. In the figures, like
reference numerals designate corresponding parts throughout the
different views. All callouts and annotations are hereby
incorporated by this reference as if fully set forth herein.
FURTHER DISCLOSURE
[0026] Light emitting diode (LED) illumination has a plethora of
advantages over incandescent to fluorescent illumination.
Advantages include longevity, low energy consumption, and small
size. White light is produced from a combination of LEDs utilizing
phosphors to convert the wavelengths of light produced by the LED
into a preselected wavelength or range of wavelengths.
[0027] In one aspect, the present disclosure provides semiconductor
light emitting devices 100 that can have a plurality of light
emitting diode (LED) strings. Each LED string can have one, or more
than one, LED. As depicted schematically in FIG. 1, the device 100
may comprise one or more LED strings (101A/101B/101C/101D) that
emit light (schematically shown with arrows). In some instances,
the LED strings can have recipient luminophoric mediums
(102A/102B/102C/102D) associated therewith. The light emitted from
the LED strings, combined with light emitted from the recipient
luminophoric mediums, can be passed through one or more optical
elements 103. Optical elements 103 may be one or more diffusers,
lenses, light guides, reflective elements, or combinations
thereof.
[0028] A recipient luminophoric medium 102A, 102B, 102C, or 102D
includes one or more luminescent materials and is positioned to
receive light that is emitted by an LED or other semiconductor
light emitting device. In some implementations, recipient
luminophoric mediums include layers having luminescent materials
that are coated or sprayed directly onto a semiconductor light
emitting device or on surfaces of the packaging thereof, and clear
encapsulants that include luminescent materials that are arranged
to partially or fully cover a semiconductor light emitting device.
A recipient luminophoric medium may include one medium layer or the
like in which one or more luminescent materials are mixed, multiple
stacked layers or mediums, each of which may include one or more of
the same or different luminescent materials, and/or multiple spaced
apart layers or mediums, each of which may include the same or
different luminescent materials. Suitable encapsulants are known by
those skilled in the art and have suitable optical, mechanical,
chemical, and thermal characteristics. In some implementations,
encapsulants can include dimethyl silicone, phenyl silicone,
epoxies, acrylics, and polycarbonates. In some implementations, a
recipient luminophoric medium can be spatially separated (i.e.,
remotely located) from an LED or surfaces of the packaging thereof,
with luminescent materials disposed within a matrix material. The
matrix material can be any material capable of retaining
luminescent materials and capable of allowing light to pass through
it. In some implementations, such spatial segregation may involve
separation of a distance of at least about 1 mm, at least about 2
mm, at least about 5 mm, or at least about 10 mm. In certain
embodiments, conductive thermal communication between a spatially
segregated luminophoric medium and one or more electrically
activated emitters is not substantial. Luminescent materials can
include phosphors, scintillators, day glow tapes, nanophosphors,
inks that glow in visible spectrum upon illumination with light,
semiconductor quantum dots, or combinations thereof.
[0029] As depicted schematically in FIG. 2, multiple solid state
packages 200 may be arranged in a single semiconductor light
emitting device 100. Individual solid state emitter packages or
groups of solid state emitter packages (e.g., wired in series) may
be separately controlled. Separate control of individual emitters,
groups of emitters, individual packages, or groups of packages, may
be provided by independently applying drive currents to the
relevant components with control elements known to those skilled in
the art. In one embodiment, at least one control circuit 201 a may
include a current supply circuit configured to independently apply
an on-state drive current to each individual solid state emitter,
group of solid state emitters, individual solid state emitter
package, or group of solid state emitter packages. Such control may
be responsive to a control signal (optionally including at least
one sensor 202 arranged to sense electrical, optical, and/or
thermal properties and/or environmental conditions), and a control
system 203 may be configured to selectively provide one or more
control signals to the at least one current supply circuit. In
various embodiments, current to different circuits or circuit
portions may be pre-set, user-defined, or responsive to one or more
inputs or other control parameters. The design and fabrication of
semiconductor light emitting devices are well known to those
skilled in the art, and hence further description thereof will be
omitted.
[0030] FIG. 3 illustrates a 1931 International Commission on
Illumination (CIE) chromaticity diagram. The 1931 CIE Chromaticity
diagram is a two-dimensional chromaticity space in which every
visible color is represented by a point having x- and
y-coordinates. Fully saturated (monochromatic) colors appear on the
outer edge of the diagram, while less saturated colors (which
represent a combination of wavelengths) appear on the interior of
the diagram. The term "saturated", as used herein, means having a
purity of at least 85%, the term "purity" having a well-known
meaning to persons skilled in the art, and procedures for
calculating purity being well-known to those of skill in the art.
The Planckian locus, or black body locus (BBL), represented by line
150 on the diagram, follows the color an incandescent black body
would take in the chromaticity space as the temperature of the
black body changes from about 1000K to 10,000 K. The black body
locus goes from deep red at low temperatures (about 1000 K) through
orange, yellowish white, white, and finally bluish white at very
high temperatures. The temperature of a black body radiator
corresponding to a particular color in a chromaticity space is
referred to as the "correlated color temperature." In general,
light corresponding to a correlated color temperature (CCT) of
about 2700 K to about 6500 K is considered to be "white" light. In
particular, as used herein, "white light" generally refers to light
having a chromaticity point that is within a 10-step MacAdam
ellipse of a point on the black body locus having a CCT between
2700K and 6500K. However, it will be understood that tighter or
looser definitions of white light can be used if desired. For
example, white light can refer to light having a chromaticity point
that is within a seven step MacAdam ellipse of a point on the black
body locus having a CCT between 2700K and 6500K. The distance from
the black body locus can be measured in the CIE 1960 chromaticity
diagram, and is indicated by the symbol .DELTA.uv, or DUV. If the
chromaticity point is above the Planckian locus the DUV is denoted
by a positive number; if the chromaticity point is below the locus,
DUV is indicated with a negative number. If the DUV is sufficiently
positive, the light source may appear greenish or yellowish at the
same CCT. If the DUV is sufficiently negative, the light source can
appear to be purple or pinkish at the same CCT. Observers may
prefer light above or below the Planckian locus for particular CCT
values. DUV calculation methods are well known by those of ordinary
skill in the art and are more fully described in ANSI C78.377,
American National Standard for Electric Lamps--Specifications for
the Chromaticity of Solid State Lighting (SSL) Products, which is
incorporated by reference herein in its entirety for all purposes.
A point representing the CIE Standard Illuminant D65 is also shown
on the diagram. The D65 illuminant is intended to represent average
daylight and has a CCT of approximately 6500K and the spectral
power distribution is described more fully in Joint ISO/CIE
Standard, ISO 10526:1999/CIE S005/E-1998, CIE Standard Illuminants
for Colorimetry, which is incorporated by reference herein in its
entirety for all purposes.
[0031] The light emitted by a light source may be represented by a
point on a chromaticity diagram, such as the 1931 CIE chromaticity
diagram, having color coordinates denoted (ccx, ccy) on the X-Y
axes of the diagram. A region on a chromaticity diagram may
represent light sources having similar chromaticity
coordinates.
[0032] In some exemplary implementations, the present disclosure
provides semiconductor light emitting devices 100 that include a
plurality of LED strings, with each LED string having a recipient
luminophoric medium that comprises a luminescent material. The
LED(s) in each string and the luminophoric medium in each string
together emit an unsaturated light having a color point within a
color range in the 1931 CIE chromaticity diagram. A "color range"
in the 1931 CIE chromaticity diagram refers to a bounded area
defining a group of color coordinates (ccx, ccy).
[0033] In some implementations, four LED strings
(101A/101B/101C/101D) are present in a device 100, and the LED
strings can have recipient luminophoric mediums
(102A/102B/102C/102D). A first LED string 101A and a first
luminophoric medium 102A together can emit a first light having a
first color point within a blue color range. The combination of the
first LED string 101A and the first luminophoric medium 102A are
also referred to herein as a "blue channel." A second LED string
101B and a second luminophoric medium 102B together can emit a
second light having a second color point within a red color range.
The combination of the second LED string 101A and the second
luminophoric medium 102A are also referred to herein as a "red
channel." A third LED string 101C and a third luminophoric medium
102C together can emit a third light having a third color point
within a yellow/green color range. The combination of the third LED
string 101A and the third luminophoric medium 102A are also
referred to herein as a "yellow/green channel." A fourth LED string
101D and a fourth luminophoric medium 102D together can emit a
fourth light having a fourth color point within a cyan color range.
The combination of the fourth LED string 101A and the fourth
luminophoric medium 102A are also referred to herein as a "cyan
channel." The first, second, third, and fourth LED strings
101A/101B/101C/101D can be provided with independently applied
on-state drive currents in order to tune the intensity of the
first, second, third, and fourth unsaturated light produced by each
string and luminophoric medium together. By varying the drive
currents in a controlled manner, the color coordinate (ccx, ccy) of
the total light that is emitted from the device 100 can be tuned.
In some implementations, the device 100 can provide light at
substantially the same color coordinate with different spectral
power distribution profiles, which can result in different light
characteristics at the same CCT. In some implementations, white
light can be generated in modes that only produce light from two or
three of the LED strings. In one implementation, white light is
generated using only the first, second, and third LED strings, i.e.
the blue, red, and yellow/green channels. In another
implementation, white light is generated using only the first,
second, and fourth LED strings, i.e., the blue, red, and cyan
channels. In some implementations, only two of the LED strings are
producing light during the generation of white light, as the other
two LED strings are not necessary to generate white light at the
desired color point with the desired color rendering
performance.
[0034] FIGS. 4A, 4B, 4C, and 4D depict suitable color ranges for
some implementations of the disclosure. FIG. 4A depicts a cyan
color range 304A defined by a line connecting the ccx, ccy color
coordinates (0.18, 0.55) and (0.27, 0.72), the constant CCT line of
9000K, the Planckian locus between 9000K and 4600K, the constant
CCT line of 4600K, and the spectral locus. FIG. 4B depicts a
yellow/green color range 303A defined by the constant CCT line of
4600K, the Planckian locus between 4600K and 550K, the spectral
locus, and a line connecting the ccx, ccy color coordinates (0.445,
0.555) and (0.38, 0.505). FIG. 4C depicts a blue color range 301A
defined by a line connecting the ccx, ccy color coordinates of the
infinity point of the Planckian locus (0.242, 0.24) and (0.12,
0.068), the Planckian locus from 4000K and infinite CCT, the
constant CCT line of 4000K, the line of purples, and the spectral
locus. FIG. 4D depicts a red color range 302A defined by the
spectral locus between the constant CCT line of 1600K and the line
of purples, the line of purples, a line connecting the ccx, ccy
color coordinates (0.61, 0.21) and (0.47, 0.28), and the constant
CCT line of 1600K. It should be understood that any gaps or
openings in the described boundaries for the color ranges 301A,
302A, 303A, 304A should be closed with straight lines to connect
adjacent endpoints in order to define a closed boundary for each
color range.
[0035] In some implementations, suitable color ranges can be
narrower than those depicted in FIGS. 4A-4D. FIG. 5 depicts some
suitable color ranges for some implementations of the disclosure. A
blue color range 301B can be defined by a 60-step MacAdam ellipse
at a CCT of 20000K, 40 points below the Planckian locus. A red
color range 302B can be defined by a 20-step MacAdam ellipse at a
CCT of 1200K, 20 points below the Planckian locus. A yellow/green
color range 303B can be defined by a 16-step MacAdam ellipse at a
CCT of 3700K, 30 points above Planckian locus. A cyan color range
304B can be defined by 30-step MacAdam ellipse at a CCT of 6000K,
68 points above the Planckian locus. FIG. 6 depicts some further
color ranges suitable for some implementations of the disclosure:
blue color range 301C, red color range 302C, yellow/green color
range 303C, and cyan color range 304C.
[0036] In some implementations, the LEDs in the first, second,
third and fourth LED strings can be LEDs with peak emission
wavelengths at or below about 535 nm. In some implementations, the
LEDs emit light with peak emission wavelengths between about 360 nm
and about 535 nm. In some implementations, the LEDs in the first,
second, third and fourth LED strings can be formed from InGaN
semiconductor materials. In some preferred implementations, the
first, second, and third LED strings can have LEDs having a peak
wavelength between about 405 nm and about 485 nm. In some
implementations the fourth LED string can have LEDs having a peak
wavelength between about 485 nm and about 520 nm. The LEDs used in
the first, second, third, and fourth LED strings may have
full-width half-maximum wavelength ranges of between about 10 nm
and about 30 nm. In some preferred implementations, the first,
second, and third LED strings can include one or more LUXEON Z
Color Line royal blue LEDs (product code LXZ1-PR01) of color bin
codes 3, 4, 5, or 6 or one or more LUXEON Z Color Line blue LEDs
(LXZ1-PB01) of color bin code 1 or 2 (Lumileds Holding B.V.,
Amsterdam, Netherlands). In some preferred implementations, the
fourth LED string can have one or more LUXEON Z Color Line blue
LEDs (LXZ1-PB01) of color bin code 5 or one or more LUXEON Z Color
Line cyan LEDs (LXZ1-PE01) color bin code 1, 2, 6, 7, 8, or 9
(Lumileds Holding B.V., Amsterdam, Netherlands). The wavelength
information for these color bins is provided in the table in FIG.
9. Similar LEDs from other manufacturers such as OSRAM GmbH and
Cree, Inc. could also be used, provided they have peak emission and
full-width half-maximum wavelengths of the appropriate values.
[0037] In implementations utilizing LEDs that emit substantially
saturated light at wavelengths between about 360 nm and about 535
nm, the device 100 can include suitable recipient luminophoric
mediums for each LED in order to produce light having color points
within the suitable blue color ranges 301A-C, red color ranges
302A-C, yellow/green color ranges 303A-C, and cyan color ranges
304A-C described herein. The light emitted by each LED string,
i.e., the light emitted from the LED(s) and associated recipient
luminophoric medium together, can have a spectral power
distribution ("SPD") having spectral power with ratios of power
across the visible wavelength spectrum from about 380 nm to about
780 nm. While not wishing to be bound by any particular theory, it
is speculated that the use of such LEDs in combination with
recipient luminophoric mediums to create unsaturated light within
the suitable color ranges 301A-C, 302A-C, 303A-C, and 304A-C
provides for improved color rendering performance for white light
across a predetermined range of CCTs from a single device 100. Some
suitable ranges for spectral power distribution ratios of the light
emitted by the four LED strings (101A/101B/101C/101D) and recipient
luminophoric mediums (102A/102B/102C/102D) together are shown in
FIGS. 7 and 8. The figures show the ratios of spectral power within
wavelength ranges, with an arbitrary reference wavelength range
selected for each color range and normalized to a value of 100.0.
FIGS. 7 and 8 show suitable minimum and maximum values for the
spectral intensities within various ranges relative to the
normalized range with a value of 100.0, for the color points within
the blue, cyan, yellow/green ("yag"), and red color ranges. While
not wishing to be bound by any particular theory, it is speculated
that because the spectral power distributions for generated light
with color points within the blue, cyan, and yellow/green color
ranges contains higher spectral intensity across visible
wavelengths as compared to lighting apparatuses and methods that
utilize more saturated colors, this allows for improved color
rendering.
[0038] Blends of luminescent materials can be used in luminophoric
mediums (102A/102B/102C/102D) to create luminophoric mediums having
the desired saturated color points when excited by their respective
LED strings (101A/101B/101C/101D). Traditionally, any desired
combined output light can be generated along a tie line between the
LED string output light color point and the saturated color point
of the associated recipient luminophoric medium by utilizing
different ratios of total luminescent material to the encapsulant
material in which it is incorporated. Increasing the amount of
luminescent material in the optical path will shift the output
light color point towards the saturated color point of the
luminophoric medium. In some instances, the desired saturated color
point of a recipient luminophoric medium can be achieved by
blending two or more luminescent materials in a ratio. The
appropriate ratios to achieve the desired saturated color point can
be determined via methods known in the art. Generally speaking, any
blend of luminescent materials can be treated as if it were a
single luminescent material, thus the ratio of luminescent
materials in the blend can be adjusted to continue to meet a target
CIE value for LED strings having different peak emission
wavelengths. Luminescent materials can be tuned for the desired
excitation in response to the selected LEDs used in the LED strings
(101A/101B/101C/101D), which may have different peak emission
wavelengths within the range of from about 360 nm to about 535 nm.
Suitable methods for tuning the excitation and emission of
luminescent materials are known in the art and may include altering
the concentrations of dopants within a phosphor, for example.
[0039] In some implementations of the present disclosure,
luminophoric mediums can be provided with combinations of two types
of luminescent materials. The first type of luminescent material
emits light at a peak emission between about 515 nm and about 590
nm in response to the associated LED string emission. The second
type of luminescent material emits at a peak emission between about
590 nm and about 700 nm in response to the associated LED string
emission. In some instances, the luminophoric mediums disclosed
herein can be formed from a combination of at least one luminescent
material of the first and second types described in this paragraph.
In implementations, the luminescent materials of the first type can
emit light at a peak emission at about 515 nm, 525 nm, 530 nm, 535
nm, 540 nm, 545 nm, 550 nm, 555 nm, 560 nm, 565 nm, 570 nm, 575 nm,
580 nm, 585 nm, or 590 nm in response to the associated LED string
emission. In preferred implementations, the luminescent materials
of the first type can emit light at a peak emission between about
520 nm to about 555 nm. In implementations, the luminescent
materials of the second type can emit light at a peak emission at
about 590 nm, about 595 nm, 600 nm, 605 nm, 610 nm, 615 nm, 620 nm,
625 nm, 630 nm, 635 nm, 640 nm, 645 nm, 650 nm, 655 nm, 670 nm, 675
nm, 680 nm, 685 nm, 690 nm, 695 nm, or 670 nm in response to the
associated LED string emission. In preferred implementations, the
luminescent materials of the first type can emit light at a peak
emission between about 600 nm to about 670 nm. Some exemplary
luminescent materials of the first and second type are disclosed
elsewhere herein and referred to as Compositions A-F.
[0040] In some implementations, the luminescent materials of the
present disclosure may comprise one or more phosphors comprising
one or more of the following materials: BaMg2Al16O27:Eu2+,
BaMg2Al16O27:Eu2+,Mn2+, CaSiO3:Pb,Mn, CaWO4:Pb, MgWO4,
Sr5Cl(PO4)3:Eu2+, Sr2P2O7:Sn2+, Sr6P5BO20:Eu, Ca5F(PO4)3:Sb,
(Ba,Ti)2P2O7:Ti, Sr5F(PO4)3:Sb,Mn, (La,Ce,Tb)PO4:Ce,Tb,
(Ca,Zn,Mg)3(PO4)2:Sn, (Sr,Mg)3(PO4)2:Sn, Y2O3:Eu3+, Mg4(F)GeO6:Mn,
LaMgAl11O19:Ce, LaPO4:Ce, SrAl12O19:Ce, BaSi2O5:Pb, SrB4O7:Eu,
Sr2MgSi2O7:Pb, Gd2O2S:Tb, Gd2O2S:Eu, Gd2O2S:Pr, Gd2O2S:Pr,Ce,F,
Y2O2S:Tb, Y2O2S:Eu, Y2O2S:Pr, Zn(0.5)Cd(0.4)S:Ag,
Zn(0.4)Cd(0.6)S:Ag, Y2SiO5:Ce, YAlO3:Ce, Y3(Al,Ga)5O12:Ce, CdS:In,
ZnO:Ga, ZnO:Zn, (Zn,Cd)S:Cu,Al, ZnCdS:Ag,Cu, ZnS:Ag, ZnS:Cu,
NaI:Tl, CsI:Tl, 6LiF/ZnS:Ag, 6LiF/ZnS:Cu,Al,Au, ZnS:Cu,Al,
ZnS:Cu,Au,Al, CaAlSiN3:Eu, (Sr,Ca)AlSiN3:Eu, (Ba,Ca,Sr,Mg)2SiO4:Eu,
Lu3Al5O12:Ce, Eu3+(Gd0.9Y0.1)3Al5O12:Bi3+,Tb3+, Y3Al5O12:Ce,
(La,Y)3Si6N11:Ce, Ca2AlSi3O2N5:Ce3+, Ca2AlSi3O2N5:Eu2+,
BaMgAl10O17:Eu, Sr5(PO4)3Cl:Eu, (Ba,Ca,Sr,Mg)2SiO4:Eu,
Sib-zAlzN8-zOz:Eu (wherein 0<z.ltoreq.4.2); M3Si6O12N2:Eu
(wherein M=alkaline earth metal element), (Mg,Ca,Sr,Ba)Si2O2N2:Eu,
Sr4Al14O25:Eu, (Ba,Sr,Ca)Al2O4:Eu, (Sr,Ba)Al2Si2O8:Eu,
(Ba,Mg)2SiO4:Eu, (Ba,Sr,Ca)2(Mg, Zn)Si2O7:Eu,
(Ba,Ca,Sr,Mg)9(Sc,Y,Lu,Gd)2(Si,Ge)6O24:Eu, Y2SiO5:CeTb,
Sr2P2O7-Sr2B2O5:Eu, Sr2Si3O8-2SrCl2:Eu, Zn2SiO4:Mn, CeMgAl11O19:Tb,
Y3Al5O12:Tb, Ca2Y8(SiO4)6O2:Tb, La3Ga5SiO14:Tb,
(Sr,Ba,Ca)Ga2S4:Eu,Tb,Sm, Y3(Al,Ga)5O12:Ce,
(Y,Ga,Tb,La,Sm,Pr,Lu)3(Al,Ga)5O12:Ce, Ca3Sc2Si3O12:Ce,
Ca3(Sc,Mg,Na,Li)2Si3O12:Ce, CaSc2O4:Ce, Eu-activated SrAl2O4:Eu,
(La,Gd,Y)2O2S:Tb, CeLaPO4:Tb, ZnS:Cu,Al, ZnS:Cu,Au,Al,
(Y,Ga,Lu,Sc,La)BO3:Ce,Tb, Na2Gd2B2O7:Ce,Tb,
(Ba,Sr)2(Ca,Mg,Zn)B2O6:K,Ce,Tb, Ca8Mg (SiO4)4Cl2:Eu,Mn,
(Sr,Ca,Ba)(Al,Ga,In)2S4:Eu, (Ca,Sr)8 (Mg,Zn)(SiO4)4Cl2:Eu,Mn,
M3Si6O9N4:Eu, Sr5Al5Si21O2N35:Eu, Sr3Si13Al3N21O2:Eu,
(Mg,Ca,Sr,Ba)2Si5N8:Eu, (La,Y)2O2S:Eu, (Y,La,Gd,Lu)2O2S:Eu,
Y(V,P)O4:Eu, (Ba,Mg)2SiO4:Eu,Mn, (Ba,Sr, Ca,Mg)2SiO4:Eu,Mn,
LiW2O8:Eu, LiW2O8:Eu,Sm, Eu2W2O9, Eu2W2O9:Nb and Eu2W2O9:Sm,
(Ca,Sr)S:Eu, YAlO3:Eu, Ca2Y8(SiO4)6O2:Eu, LiY9(SiO4)6O2:Eu,
(Y,Gd)3Al5O12:Ce, (Tb,Gd)3Al5O12:Ce, (Mg,Ca,Sr,Ba)2Si5(N,O)8:Eu,
(Mg,Ca,Sr,Ba)Si(N,O)2:Eu, (Mg,Ca,Sr,Ba)AlSi(N,O)3:Eu,
(Sr,Ca,Ba,Mg)10(PO4)6Cl2:Eu, Mn, Eu,Ba3MgSi2O8:Eu,Mn,
(Ba,Sr,Ca,Mg)3(Zn,Mg)Si2O8:Eu,Mn, (k-x)MgO.xAF2.GeO2:yMn4+ (wherein
k=2.8 to 5, x=0.1 to 0.7, y=0.005 to 0.015, A=Ca, Sr, Ba, Zn or a
mixture thereof), Eu-activated .alpha.-Sialon, (Gd,Y,Lu,La)2O3:Eu,
Bi, (Gd,Y,Lu,La)2O2S:Eu,Bi, (Gd,Y, Lu,La)VO4:Eu,Bi, SrY2S4:Eu,Ce,
CaLa2S4:Ce,Eu, (Ba,Sr,Ca)MgP2O7:Eu, Mn,
(Sr,Ca,Ba,Mg,Zn)2P2O7:Eu,Mn, (Y,Lu)2WO6:Eu,Ma,
(Ba,Sr,Ca)xSiyNz:Eu,Ce (wherein x, y and z are integers equal to or
greater than 1), (Ca,Sr,Ba,Mg)10(PO4)6(F,Cl,Br,OH):Eu,Mn,
((Y,Lu,Gd,Tb)1-x-yScxCey)2(Ca,Mg)(Mg,Zn)2+rSiz-qGeqO12+.delta.,
SrAlSi4N7, Sr2Al2Si9O2N14:Eu, M1aM2bM3cOd (wherein M1=activator
element including at least Ce, M2=bivalent metal element,
M3=trivalent metal element, 0.0001.ltoreq.a.ltoreq.0.2,
0.8.ltoreq.b.ltoreq.1.2, 1.6.ltoreq.c.ltoreq.2.4 and
3.2.ltoreq.d.ltoreq.4.8), A2+xMyMnzFn (wherein A=Na and/or K; M=Si
and Al, and -1.ltoreq.x.ltoreq.1, 0.9.ltoreq.y+z.ltoreq.1.1,
0.001.ltoreq.z.ltoreq.0.4 and 5.ltoreq.n.ltoreq.7), KSF/KSNAF, or
(La1-x-y, Eux, Lny)2O2S (wherein 0.02.ltoreq.x.ltoreq.0.50 and
0.ltoreq.y.ltoreq.0.50, Ln=Y3+, Gd3+, Lu3+, Sc3+, Sm3+ or Er3+). In
some preferred implementations, the luminescent materials may
comprise phosphors comprising one or more of the following
materials: CaAlSiN3:Eu, (Sr,Ca)AlSiN3:Eu, BaMgAl10O17:Eu,
(Ba,Ca,Sr,Mg)2SiO4:Eu, .beta.-SiAlON, Lu3Al5O12:Ce,
Eu3+(Cd0.9Y0.1)3Al5O12:Bi3+,Tb3+, Y3Al5O12:Ce, La3Si6N11:Ce,
(La,Y)3Si6N11:Ce, Ca2AlSi3O2N5:Ce3+, Ca2AlSi3O2N5:Ce3+,Eu2+,
Ca2AlSi3O2N5:Eu2+, BaMgAl10O17:Eu2+, Sr4.5Eu0.5(PO4)3Cl, or
M1aM2bM3cOd (wherein M1=activator element comprising Ce,
M2=bivalent metal element, M3=trivalent metal element,
0.0001.ltoreq.a.ltoreq.0.2, 0.8.ltoreq.b.ltoreq.1.2,
1.6.ltoreq.c.ltoreq.2.4 and 3.2.ltoreq.d.ltoreq.4.8). In further
preferred implementations, the luminescent materials may comprise
phosphors comprising one or more of the following materials:
CaAlSiN3:Eu, BaMgAl10O17:Eu, Lu3Al5O12:Ce, or Y3Al5O12:Ce.
[0041] Luminescent materials can include an inorganic or organic
phosphor; silicate-based phosphors; aluminate-based phosphors;
aluminate-silicate phosphors; nitride phosphors; sulfate phosphor;
oxy-nitrides and oxy-sulfate phosphors; or garnet materials. The
phosphor materials are not limited to any specific examples and can
include any phosphor material known in the art with the desired
emission spectra in response to the selected excitation light
source, i.e. the associated LED or LEDs that produce light that
impacts the recipient luminophoric medium. The d50 (average
diameter) value of the particle size of the phosphor luminescent
materials can be between about 1 and about 50 .mu.m, preferably
between about 10 .mu.m and about 20 .mu.m, and more preferably
between about 13.5 .mu.m and about 18 .mu.m. Quantum dots are also
known in the art. The color of light produced is from the quantum
confinement effect associated with the nano-crystal structure of
the quantum dots. The energy level of each quantum dot relates
directly to the size of the quantum dot. Suitable semiconductor
materials for quantum dots are known in the art and may include
materials formed from elements from groups II-V, II-VI, or IV-VI in
particles having core, core/shell, or core/shells structures and
with or without surface-modifying ligands.
[0042] Tables 1 and 2 shows aspects of some exemplary luminescent
compositions and properties, referred to as Compositions
"A"-"F".
TABLE-US-00001 TABLE 1 Suitable Ranges Exemplary Emission
Embodiment Peak FWHM Exemplary density Emission FWHM Range Range
Material(s) (g/mL) Peak (nm) (nm) (nm) (nm) Composition Luag:
Cerium 6.73 535 95 530-540 90-100 "A" doped lutetium aluminum
garnet (Lu.sub.3Al.sub.5O.sub.12) Composition Yag: Cerium doped 4.7
550 110 545-555 105-115 "B" yttrium aluminum garnet
(Y.sub.3Al.sub.5O.sub.12) Composition a 650 nm-peak 3.1 650 90
645-655 85-95 "C" wavelength emission phosphor: Europium doped
calcium aluminum silica nitride (CaAlSiN.sub.3) Composition a 525
nm-peak 3.1 525 60 520-530 55-65 "D" wavelength emission phosphor:
GBAM: BaMgAl.sub.10O.sub.17:Eu Composition a 630 nm-peak 5.1 630 40
625-635 35-45 "E" wavelength emission quantum dot: any
semiconductor quantum dot material of appropriate size for desired
emission wavelengths Composition a 610 nm-peak 5.1 610 40 605-615
35-45 "F" wavelength emission quantum dot: any semiconductor
quantum dot material of appropriate size for desired emission
wavelengths Matrix "M" Silicone binder 1.1 mg/ mm.sup.3
TABLE-US-00002 TABLE 2 Implementation 1 Implementation 2 Exemplary
particle refractive particle refractive Designator Material(s) size
(d50) index size index Composition "A" Luag: Cerium doped 18.0
.mu.m 1.84 40 .mu.m 1.8 lutetium aluminum garnet
(Lu.sub.3Al.sub.5O.sub.12) Composition "B" Yag: Cerium doped 13.5
.mu.m 1.82 30 .mu.m 1.85 yttrium aluminum garnet
(Y.sub.3Al.sub.5O.sub.12) Composition "C" a 650 nm-peak 15.0 .mu.m
1.8 10 .mu.m 1.8 wavelength emission phosphor: Europium doped
calcium aluminum silica nitride (CaAlSiN.sub.3) Composition "D" a
525 nm-peak 15.0 .mu.m 1.8 n/a n/a wavelength emission phosphor:
GBAM: BaMgAl.sub.10O.sub.17:Eu Composition "E" a 630 nm-peak 10.0
nm 1.8 n/a n/a wavelength emission quantum dot: any semiconductor
quantum dot material of appropriate size for desired emission
wavelengths Composition "F" a 610 nm-peak 10.0 nm 1.8 n/a n/a
wavelength emission quantum dot: any semiconductor quantum dot
material of appropriate size for desired emission wavelengths
Matrix "M" Silicone binder 1.545 1.545
[0043] Blends of Compositions A-F can be used in luminophoric
mediums (102A/102B/102C/102D) to create luminophoric mediums having
the desired saturated color points when excited by their respective
LED strings (101A/101B/101C/101D). In some implementations, one or
more blends of one or more of Compositions A-F can be used to
produce luminophoric mediums (102A/102B/102C/102D). In some
preferred implementations, one or more of Compositions A, B, and D
and one or more of Compositions C, E, and F can be combined to
produce luminophoric mediums (102A/102B/102C/102D). In some
preferred implementations, the encapsulant for luminophoric mediums
(102A/102B/102C/102D) comprises a matrix material having density of
about 1.1 mg/mm3 and refractive index of about 1.545. Other matrix
materials having refractive indices of between about 1.4 and about
1.6 can also be used in some implementations. In some
implementations, Composition A can have a refractive index of about
1.82 and a particle size from about 18 micrometers to about 40
micrometers. In some implementations, Composition B can have a
refractive index of about 1.84 and a particle size from about 13
micrometers to about 30 micrometers. In some implementations,
Composition C can have a refractive index of about 1.8 and a
particle size from about 10 micrometers to about 15 micrometers. In
some implementations, Composition D can have a refractive index of
about 1.8 and a particle size from about 10 micrometers to about 15
micrometers. Suitable phosphor materials for Compositions A, B, C,
and D are commercially available from phosphor manufacturers such
as Mitsubishi Chemical Holdings Corporation (Tokyo, Japan),
Intematix Corporation (Fremont, Calif.), EMD Performance Materials
of Merck KGaA (Darmstadt, Germany), and PhosphorTech Corporation
(Kennesaw, Ga.).
[0044] In some implementations, Composition A can be selected from
the "BG-801" product series sold by Mitsubishi Chemical
Corporation. The BG-801 series is provided as cerium doped lutetium
aluminum garnet (Lu3Al5O12). For some implementations, other
phosphor materials are also suitable and can have peak emission
wavelengths of between about 530 nm and about 560 nm, FWHM of
between about 90 nm and about 110 nm, and particle sizes (d50) of
between about 10 .mu.m and about 50 .mu.m.
[0045] In some implementations, Composition B can be selected from
the "BY-102" or "BY-202" product series sold by Mitsubishi Chemical
Corporation. The BY-102 series is provided as cerium doped yttrium
aluminum garnet (Y3Al5O12). The BY-202 series is provided as
(La,Y)3Si6N11:Ce. For some implementations, other phosphor
materials are also suitable and can have peak emission wavelengths
of between about 545 nm and about 560 nm, FWHM of between about 90
nm and about 115 nm, and particle sizes (d50) of between about 10
.mu.m and about 50 .mu.m.
[0046] In some implementations, Composition C can be selected from
the "BR-101", "BR-102", or "BR-103" product series sold by
Mitsubishi Chemical Corporation. The BR-101 series is provided as
europium doped calcium aluminum silica nitride (CaAlSiN3). The
BR-102 series is provided as europium doped strontium substituted
calcium aluminum silica nitride (Sr,Ca)AlSiN3. The BR-103 series is
provided as europium doped strontium substituted calcium aluminum
silica nitride (Sr,Ca)AlSiN3. For some implementations, other
phosphor materials are also suitable and can have peak emission
wavelengths of between about 610 nm and about 650 nm, FWHM of
between about 80 nm and about 105 nm, and particle sizes (d50) of
between about 5 .mu.m and about 50 .mu.m.
[0047] In some implementations, Composition D can be selected from
the "VG-401" product series sold by Mitsubishi Chemical
Corporation. The VG-401 series is provided as GBAM: BaMgAl10O17:Eu.
For some implementations, other phosphor materials are also
suitable and can have peak emission wavelengths of between about
510 nm and about 540 nm, FWHM of between about 45 nm and about 75
nm, and particle sizes (d50) of between about 5 .mu.m and about 50
.mu.m.
EXAMPLES
General Simulation Method.
[0048] Devices having four LED strings with particular color points
were simulated. For each device, four LED strings and recipient
luminophoric mediums with particular emissions were selected, and
spectral power distributions for the resulting four channels (blue,
red, yellow/green, and cyan) were calculated.
[0049] The calculations were performed with Scilab (Scilab
Enterprises, Versailles, France), LightTools (Synopsis, Inc.,
Mountain View, Calif.), and custom software created using Python
(Python Software Foundation, Beaverton, Oreg.). Each LED string was
simulated with an LED emission spectrum and excitation and emission
spectra of luminophoric medium(s). For luminophoric mediums
comprising phosphors, the simulations also included the absorption
spectrum and particle size of phosphor particles. The LED strings
generating combined emissions within blue, red and yellow/green
color regions were prepared using spectra of a LUXEON Z Color Line
royal blue LED (product code LXZ1-PR01) of color bin codes 3, 4, 5,
or 6 or a LUXEON Z Color Line blue LED (LXZ1-PB01) of color bin
code 1 or 2 (Lumileds Holding B.V., Amsterdam, Netherlands). The
LED strings generating combined emissions with color points within
the cyan regions were prepared using spectra of a LUXEON Z Color
Line blue LED (LXZ1-PB01) of color bin code 5 or LUXEON Z Color
Line cyan LED (LXZ1-PE01) color bin code 1, 8, or 9 (Lumileds
Holding B.V., Amsterdam, Netherlands). Similar LEDs from other
manufacturers such as OSRAM GmbH and Cree, Inc. could also be
used.
[0050] The luminophoric mediums used in the following examples were
calculated as combinations of one or more of Compositions A, B, and
D and one or more of Compositions C, E, and F as described more
fully elsewhere herein. Those of skill in the art appreciate that
various combinations of LEDs and luminophoric blends can be
combined to generate combined emissions with desired color points
on the 1931 CIE chromaticity diagram and the desired spectral power
distributions.
Example 1
[0051] A semiconductor light emitting device was simulated having
four LED strings. A first LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a blue color point with a 1931 CIE
chromaticity diagram color point of (0.2625, 0.1763). A second LED
string is driven by a blue LED having peak emission wavelength of
approximately 450 nm to approximately 455 nm, utilizes a recipient
luminophoric medium, and generates a combined emission of a red
color point with a 1931 CIE chromaticity diagram color point of
(0.5842, 0.3112). A third LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a yellow/green color point with a 1931 CIE
chromaticity diagram color point of (0.4482, 0.5258). A fourth LED
string is driven by a cyan LED having a peak emission wavelength of
approximately 505 nm, utilizes a recipient luminophoric medium, and
generates a combined emission of a cyan color point with a 1931 CIE
chromaticity diagram color point of (0.3258, 0.5407). Table 3 below
shows the spectral power distributions for the blue, red,
yellow-green, and cyan color points generated by the device of this
Example, with spectral power shown within wavelength ranges in
nanometers from 380 nm to 780 nm, with an arbitrary reference
wavelength range selected for each color range and normalized to a
value of 100.0:
TABLE-US-00003 TABLE 3 380-420 421-460 461-500 501-540 541-580
581-620 621-660 661-700 701-740 741-780 Blue 0.4 100.0 20.9 15.2
25.3 26.3 25.1 13.9 5.2 1.6 Red 0.0 9.6 2.0 1.4 9.0 48.5 100.0 73.1
29.5 9.0 Yellow- 1.0 1.1 5.7 75.8 100.0 83.6 69.6 40.9 15.6 4.7
Green Cyan 0.1 0.5 53.0 100.0 65.0 41.6 23.1 11.6 4.2 0.6
[0052] Tables 4 and 5 show exemplary luminophoric mediums suitable
for the recipient luminophoric mediums for the blue, red,
yellow/green, and cyan channels of this Example, using the
Compositions A-F from Implementation 1 or Implementation 2 as
described in Tables 1 and 2 above.
TABLE-US-00004 TABLE 4 Volumetric Ratios - Using "Implementation 1"
Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. Comp.
Comp. A B C D E F Matrix Blue Blend 1 1.54 0.87 97.60 Blue Blend 2
1.68 1.89 96.43 Blue Blend 3 1.35 0.58 1.49 96.58 Blue Blend 4 1.84
1.34 96.82 Blue Blend 5 0.86 1.51 0.93 96.69 Blue Blend 6 0.89 1.73
0.35 97.03 Blue Blend 7 1.34 1.11 97.55 Red Blend 1 1.66 24.23
74.11 Red Blend 2 1.96 24.72 73.32 Red Blend 3 0.00 3.43 26.48
70.10 Red Blend 4 21.36 1.70 76.94 Red Blend 5 0.80 24.49 1.22
73.49 Red Blend 6 0.22 12.74 11.75 75.28 Red Blend 7 0.07 15.34
7.90 76.70 Yellow/Green Blend 1 54.92 1.82 43.26 Yellow/Green Blend
2 56.18 3.90 0.07 39.86 Yellow/Green Blend 3 2.49 20.51 77.00
Yellow/Green Blend 4 5.21 5.34 46.86 42.59 Yellow/Green Blend 5
38.63 1.55 1.84 57.98 Cyan Blend 1 4.45 9.16 86.38 Cyan Blend 2
6.29 11.67 82.03 Cyan Blend 3 2.03 3.16 9.94 84.86 Cyan Blend 4
6.30 4.42 89.28 Cyan Blend 5 3.30 6.93 1.41 88.36 Cyan Blend 6 9.12
11.67 9.29 69.92 Cyan Blend 7 4.82 9.43 6.60 79.15
TABLE-US-00005 TABLE 5 Volumetric Ratios - Using "Implementation 2"
Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. Comp.
Comp. A B C D E F Matrix Blue Blend 8 1.13 1.12 97.75 Blue Blend 9
0.73 2.38 96.89 Blue Blend 10 0.1 0.14 1.6 97.16 Red Blend 8 0.58
16.23 83.19 Red Blend 9 0.42 16.63 82.95 Red Blend 10 1.79 3.09
17.6 77.52 Yellow/Green Blend 6 94.48 0.04 3.51 1.97 Cyan Blend 8
3.07 3.67 93.26 Cyan Blend 9 5.32 4.2 90.48
Example 2
[0053] A semiconductor light emitting device was simulated having
four LED strings. A first LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a blue color point with a 1931 CIE
chromaticity diagram color point of (0.2625, 0.1763). A second LED
string is driven by a blue LED having peak emission wavelength of
approximately 450 nm to approximately 455 nm, utilizes a recipient
luminophoric medium, and generates a combined emission of a red
color point with a 1931 CIE chromaticity diagram color point of
(0.5842, 0.3112). A third LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a yellow/green color point with a 1931 CIE
chromaticity diagram color point of (0.5108, 0.4708). A fourth LED
string is driven by a cyan LED having a peak emission wavelength of
approximately 505 nm, utilizes a recipient luminophoric medium, and
generates a combined emission of a cyan color point with a 1931 CIE
chromaticity diagram color point of (0.3258, 0.5407). Table 6 below
shows the spectral power distributions for the blue, red,
yellow-green, and cyan color points generated by the device of this
Example, with spectral power shown within wavelength ranges in
nanometers from 380 nm to 780 nm, with an arbitrary reference
wavelength range selected for each color range and normalized to a
value of 100.0:
TABLE-US-00006 TABLE 6 380-420 421-460 461-500 501-540 541-580
581-620 621-660 661-700 701-740 741-780 Blue 0.3 100.0 196.1 33.0
40.3 38.2 34.2 20.4 7.8 2.3 Red 0.0 157.8 2.0 1.4 9.0 48.5 100.0
73.1 29.5 9.0 Yellow- 0.0 1.0 4.2 56.6 100.0 123.4 144.9 88.8 34.4
10.5 Green Cyan 0.1 0.5 53.0 100.0 65.0 41.6 23.1 11.6 4.2 0.6
[0054] Tables 7 and 8 show exemplary luminophoric mediums suitable
for the recipient luminophoric mediums for the blue, red,
yellow/green, and cyan channels of this Example, using the
Compositions A-F from Implementation 1 or Implementation 2 as
described in Tables 1 and 2 above.
TABLE-US-00007 TABLE 7 Volumetric Ratios - Using "Implementation 1"
Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. Comp.
Comp. A B C D E F Matrix Blue Blend 1 1.54 0.87 97.59 Blue Blend 2
1.34 1.11 97.55 Blue Blend 3 1.68 1.89 96.43 Blue Blend 4 1.35 0.58
1.49 96.58 Blue Blend 5 1.84 1.34 96.82 Blue Blend 6 0.86 1.51 0.93
96.69 Blue Blend 7 0.89 1.73 0.35 97.03 Red Blend 1 1.66 24.23
74.11 Red Blend 2 0.07 15.34 7.90 76.70 Red Blend 3 1.96 24.72
73.32 Red Blend 4 3.43 26.48 70.10 Red Blend 5 21.36 1.70 76.94 Red
Blend 6 0.80 24.49 1.22 73.49 Red Blend 7 0.22 12.74 11.75 75.28
Yellow/Green Blend 1 50.54 0.02 49.44 Yellow/Green Blend 2 37.70
1.40 0.61 60.28 Yellow/Green Blend 3 43.22 15.08 41.70 Yellow/Green
Blend 4 6.51 19.90 73.59 Yellow/Green Blend 5 5.01 15.89 37.71
41.39 Yellow/Green Blend 6 24.41 9.45 11.02 55.11 Cyan Blend 1 4.45
9.16 86.38 Cyan Blend 2 4.82 9.43 6.60 79.15 Cyan Blend 3 6.29
11.67 82.03 Cyan Blend 4 2.03 3.16 9.94 84.86 Cyan Blend 5 6.30
4.42 89.28 Cyan Blend 6 3.30 6.93 1.41 88.36 Cyan Blend 7 9.12
11.67 9.29 69.92
TABLE-US-00008 TABLE 8 Volumetric Ratios - Using "Implementation 2"
Compositions from Tables 1 and 2 Comp. A Comp. B Comp. C Comp. D
Comp. E Comp. F Matrix Blue Blend 8 0 1.13 1.12 97.75 Blue Blend 9
0.73 0 2.38 96.89 Blue Blend 10 0.1 0.14 1.6 98.16 Red Blend 8 0
0.58 16.23 83.19 Red Blend 9 0.42 0 16.63 82.95 Red Blend 10 1.79
3.09 17.6 77.52 Cyan Blend 8 0 3.07 3.67 93.26 Cyan Blend 9 5.32 0
4.2 90.48
Example 3
[0055] A semiconductor light emitting device was simulated having
four LED strings. A first LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a blue color point with a 1931 CIE
chromaticity diagram color point of (0.2219, 0.1755). A second LED
string is driven by a blue LED having peak emission wavelength of
approximately 450 nm to approximately 455 nm, utilizes a recipient
luminophoric medium, and generates a combined emission of a red
color point with a 1931 CIE chromaticity diagram color point of
(0.5702, 0.3869). A third LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a yellow/green color point with a 1931 CIE
chromaticity diagram color point of (0.3722, 0.4232). A fourth LED
string is driven by a cyan LED having a peak emission wavelength of
approximately 505 nm, utilizes a recipient luminophoric medium, and
generates a combined emission of a cyan color point with a 1931 CIE
chromaticity diagram color point of (0.3704, 0.5083). Table 9 below
shows the spectral power distributions for the blue, red,
yellow-green, and cyan color points generated by the device of this
Example, with spectral power shown within wavelength ranges in
nanometers from 380 nm to 780 nm, with an arbitrary reference
wavelength range selected for each color range and normalized to a
value of 100.0:
TABLE-US-00009 TABLE 9 380-420 421-460 461-500 501-540 541-580
581-620 621-660 661-700 701-740 741-780 Blue 8.1 100.0 188.1 35.6
40.0 70.0 80.2 12.4 2.3 1.0 Red 0.7 2.1 4.1 12.2 20.5 51.8 100.0
74.3 29.3 8.4 Yellow- 1.0 25.3 52.7 77.5 100.0 80.5 62.0 35.1 13.3
4.0 Green Cyan 0.4 1.5 55.5 100.0 65.3 59.9 57.1 35.0 13.5 4.1
[0056] Tables 10 and 11 show exemplary luminophoric mediums
suitable for the recipient luminophoric mediums for the blue, red,
yellow/green, and cyan channels of this Example, using the
Compositions A-F from Implementation 1 or Implementation 2 as
described in Tables 1 and 2 above.
TABLE-US-00010 TABLE 10 Volumetric Ratios - Using "Implementation
1" Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. Comp.
Comp. A B C D E F Matrix Blue Blend 1 1.47 98.53 Blue Blend 2 1.39
0.01 98.60 Blue Blend 3 1.84 0.55 97.60 Blue Blend 4 1.54 0.55 0.07
97.84 Blue Blend 5 0.79 1.49 97.72 Blue Blend 6 0.74 0.31 1.33
97.63 Blue Blend 7 1.21 0.66 98.13 Red Blend 1 11.66 21.77 66.57
Red Blend 2 5.59 17.46 7.21 69.74 Red Blend 3 13.17 25.45 61.38 Red
Blend 4 6.47 7.75 24.90 60.88 Red Blend 5 16.55 8.34 75.11 Red
Blend 6 2.37 24.60 11.89 61.13 Red Blend 7 4.57 16.51 12.47 66.44
Yellow/Green Blend 1 16.75 2.44 80.81 Yellow/Green Blend 2 32.98
8.23 0.06 58.73 Yellow/Green Blend 3 2.90 7.46 89.64 Yellow/Green
Blend 4 0.79 4.25 17.43 77.53 Yellow/Green Blend 5 10.62 1.98 2.24
85.17 Cyan Blend 1 16.88 83.12 Cyan Blend 2 2.29 16.58 8.02 73.11
Cyan Blend 3 5.00 16.18 78.82 Cyan Blend 4 0.43 2.74 15.68 81.14
Cyan Blend 5 12.05 1.75 86.20 Cyan Blend 6 0.03 10.52 2.79 86.66
Cyan Blend 7 4.98 14.42 12.74 67.86
TABLE-US-00011 TABLE 11 Volumetric Ratios - Using "Implementation
2" Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. A Comp.
B Comp. C D E F Matrix Blue Blend 8 1.06 98.94 Blue Blend 9 0.88
0.64 98.48 Blue Blend 10 2.92 1.62 95.46 Red Blend 8 4.02 13.36
82.62 Red Blend 9 3.25 15.67 81.08 Red Blend 10 16.56 15.37 16.88
51.19 Yellow Blend 6 39.09 3.06 1.16 56.69 Cyan Blend 8 2.0 6.71
91.29 Cyan Blend 9 3.83 6.51 89.66
Example 4
[0057] A semiconductor light emitting device was simulated having
four LED strings. A first LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a blue color point with a 1931 CIE
chromaticity diagram color point of (0.2387, 0.1692). A second LED
string is driven by a blue LED having peak emission wavelength of
approximately 450 nm to approximately 455 nm, utilizes a recipient
luminophoric medium, and generates a combined emission of a red
color point with a 1931 CIE chromaticity diagram color point of
(0.5563, 0.3072). A third LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a yellow/green color point with a 1931 CIE
chromaticity diagram color point of (0.4494, 0.5161). A fourth LED
string is driven by a cyan LED having a peak emission wavelength of
approximately 505 nm, utilizes a recipient luminophoric medium, and
generates a combined emission of a cyan color point with a 1931 CIE
chromaticity diagram color point of (0.3548, 0.5484). Table 12
below shows the spectral power distributions for the blue, red,
yellow-green, and cyan color points generated by the device of this
Example, with spectral power shown within wavelength ranges in
nanometers from 380 nm to 780 nm, with an arbitrary reference
wavelength range selected for each color range and normalized to a
value of 100.0:
TABLE-US-00012 TABLE 12 380-420 421-460 461-500 501-540 541-580
581-620 621-660 661-700 701-740 741-780 Blue 1.9 100.0 34.4 32.1
40.5 29.0 15.4 5.9 2.8 1.5 Red 14.8 10.5 6.7 8.7 8.7 102.8 100.0
11.0 1.5 1.1 Yellow- 1.1 2.3 5.9 61.0 100.0 85.0 51.0 12.6 3.2 1.0
Green Cyan 0.7 1.6 39.6 100.0 80.4 53.0 24.9 9.5 3.3 1.2
[0058] Tables 13 and 14 show exemplary luminophoric mediums
suitable for the recipient luminophoric mediums for the blue, red,
yellow/green, and cyan channels of this Example, using the
Compositions A-F from Implementation 1 or Implementation 2 as
described in Tables 1 and 2 above.
TABLE-US-00013 TABLE 13 Volumetric Ratios - Using "Implementation
1" Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. Comp.
Comp. A B C D E F Matrix Blue Blend 1 1.49 0.13 98.38 Blue Blend 2
1.46 0.15 98.39 Blue Blend 3 1.63 1.12 97.24 Blue Blend 4 1.36 0.53
0.71 97.41 Blue Blend 5 1.24 1.34 97.43 Blue Blend 6 0.75 0.84 1.04
97.37 Blue Blend 7 0.99 1.27 97.74 Red Blend 1 2.18 20.26 77.55 Red
Blend 2 0.40 13.83 5.57 80.20 Red Blend 3 2.57 20.93 76.50 Red
Blend 4 0.68 2.15 22.07 75.10 Red Blend 5 17.50 2.11 80.40 Red
Blend 6 1.62 20.45 0.85 77.07 Red Blend 7 0.47 11.38 9.48 78.67
Yellow/Green Blend 1 46.13 3.33 50.54 Yellow/Green Blend 2 74.85
15.25 0.09 9.81 Yellow/Green Blend 3 2.99 18.14 78.87 Yellow/Green
Blend 4 5.55 5.59 38.75 50.11 Yellow/Green Blend 5 32.93 2.40 3.11
61.56 Cyan Blend 1 12.31 8.97 78.72 Cyan Blend 2 18.36 7.33 1.03
73.28 Cyan Blend 3 17.39 14.53 68.08 Cyan Blend 4 1.58 16.41 6.74
75.27 Cyan Blend 5 4.42 6.30 89.28 Cyan Blend 6 9.00 1.00 8.02
81.98 Cyan Blend 7 25.77 11.28 8.70 54.26
TABLE-US-00014 TABLE 14 Volumetric Ratios - Using "Implementation
2" Compositions from Tables 1 and 2 Comp. A Comp. B Comp. C Comp. D
Comp. E Comp. F Matrix Blue Blend 8 1.06 98.94 Blue Blend 9 0.76
1.45 97.79 Blue Blend 10 0.08 0.12 1.52 98.28 Red Blend 8 0.74
14.13 85.13 Red Blend 9 0.6 14.65 84.75 Red Blend 10 3.07 3.52
14.75 78.66 Cyan Blend 8 6.31 1.13 92.56 Cyan Blend 9 10.0 2.5
87.50
Example 5
[0059] A semiconductor light emitting device was simulated having
four LED strings. A first LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a blue color point with a 1931 CIE
chromaticity diagram color point of (0.2524, 0.223). A second LED
string is driven by a blue LED having peak emission wavelength of
approximately 450 nm to approximately 455 nm, utilizes a recipient
luminophoric medium, and generates a combined emission of a red
color point with a 1931 CIE chromaticity diagram color point of
(0.5941, 0.3215). A third LED string is driven by a blue LED having
peak emission wavelength of approximately 450 nm to approximately
455 nm, utilizes a recipient luminophoric medium, and generates a
combined emission of a yellow/green color point with a 1931 CIE
chromaticity diagram color point of (0.4338, 0.5195). A fourth LED
string is driven by a cyan LED having a peak emission wavelength of
approximately 505 nm, utilizes a recipient luminophoric medium, and
generates a combined emission of a cyan color point with a 1931 CIE
chromaticity diagram color point of (0.3361, 0.5257). Table 15
below shows the spectral power distributions for the blue, red,
yellow-green, and cyan color points generated by the device of this
Example, with spectral power shown within wavelength ranges in
nanometers from 380 nm to 780 nm, with an arbitrary reference
wavelength range selected for each color range and normalized to a
value of 100.0:
TABLE-US-00015 TABLE 15 380-420 421-460 461-500 501-540 541-580
581-620 621-660 661-700 701-740 741-780 Blue 1.9 100.0 34.4 32.1
40.5 29.0 15.4 5.9 2.8 1.5 Red 0.2 8.5 3.0 5.5 9.5 60.7 100.0 1.8
0.5 0.3 Yellow- 0.8 5.6 6.3 73.4 100.0 83.8 48.4 19.5 6.5 2.0 Green
Cyan 0.2 1.4 58.6 100.0 62.0 47.5 28.2 6.6 1.8 0.6
[0060] Tables 16 and 17 show exemplary luminophoric mediums
suitable for the recipient luminophoric mediums for the blue, red,
yellow/green, and cyan channels of this Example, using the
Compositions A-F from Implementation 1 or Implementation 2 as
described in Tables 1 and 2 above.
TABLE-US-00016 TABLE 16 Volumetric Ratios - Using "Implementation
1" Compositions from Tables 1 and 2 Comp. Comp. Comp. Comp. Comp.
Comp. A B C D E F Matrix Blue Blend 1 2.29 97.70 Blue Blend 2 2.46
0.15 97.39 Blue Blend 3 3.01 0.99 95.99 Blue Blend 4 2.34 1.01 0.29
96.35 Blue Blend 5 1.25 2.20 96.55 Blue Blend 6 1.25 0.60 2.09
96.06 Blue Blend 7 1.88 1.16 96.96 Red Blend 1 2.12 26.06 71.82 Red
Blend 2 0.24 16.36 9.03 74.37 Red Blend 3 2.43 26.68 70.89 Red
Blend 4 1.02 1.64 28.61 68.72 Red Blend 5 22.60 2.22 75.19 Red
Blend 6 1.11 26.37 1.45 71.07 Red Blend 7 0.38 13.79 12.99 72.84
Yellow/Green Blend 1 42.76 1.82 55.43 Yellow/Green Blend 2 44.06
3.54 0.05 52.35 Yellow/Green Blend 3 2.60 16.60 80.80 Yellow/Green
Blend 4 3.59 4.91 38.01 53.50 Yellow/Green Blend 5 30.44 1.49 1.87
66.20 Cyan Blend 1 1.51 11.87 86.62 Cyan Blend 2 2.55 10.92 9.29
77.25 Cyan Blend 3 2.06 12.75 85.19 Cyan Blend 4 3.42 10.40 86.17
Cyan Blend 5 8.17 2.54 89.29 Cyan Blend 6 0.63 1.67 8.85 88.85 Cyan
Blend 7 4.97 12.58 10.32 72.12
TABLE-US-00017 TABLE 17 Volumetric Ratios - Using "Implementation
2" Compositions from Tables 1 and 2 Comp. A Comp. B Comp. C Comp. D
Comp. E Comp. F Matrix Blue Blend 8 1.42 0.03 98.55 Blue Blend 9
1.25 1.2 97.55 Blue Blend 10 0.135 0.135 1.080 98.65 Red Blend 8
0.74 17.04 82.22 Red Blend 9 0.58 17.52 81.90 Red Blend 10 2.3 3.97
18.94 74.79 Cyan Blend 8 2.01 5.38 92.61 Cyan Blend 9 3.65 5.55
90.80
[0061] Those of ordinary skill in the art will appreciate that a
variety of materials can be used in the manufacturing of the
components in the devices and systems disclosed herein. Any
suitable structure and/or material can be used for the various
features described herein, and a skilled artisan will be able to
select an appropriate structures and materials based on various
considerations, including the intended use of the systems disclosed
herein, the intended arena within which they will be used, and the
equipment and/or accessories with which they are intended to be
used, among other considerations. Conventional polymeric,
metal-polymer composites, ceramics, and metal materials are
suitable for use in the various components. Materials hereinafter
discovered and/or developed that are determined to be suitable for
use in the features and elements described herein would also be
considered acceptable.
[0062] When ranges are used herein for physical properties, such as
molecular weight, or chemical properties, such as chemical
formulae, all combinations, and subcombinations of ranges for
specific exemplar therein are intended to be included.
[0063] The disclosures of each patent, patent application, and
publication cited or described in this document are hereby
incorporated herein by reference, in its entirety.
[0064] Those of ordinary skill in the art will appreciate that
numerous changes and modifications can be made to the exemplars of
the disclosure and that such changes and modifications can be made
without departing from the spirit of the disclosure. It is,
therefore, intended that the appended claims cover all such
equivalent variations as fall within the true spirit and scope of
the disclosure.
* * * * *