U.S. patent application number 12/834468 was filed with the patent office on 2010-11-25 for high luminous flux warm white solid state lighting device.
Invention is credited to Thong Bui, Israel J. Morejon, Jinhui Zhai.
Application Number | 20100295069 12/834468 |
Document ID | / |
Family ID | 42239445 |
Filed Date | 2010-11-25 |
United States Patent
Application |
20100295069 |
Kind Code |
A1 |
Zhai; Jinhui ; et
al. |
November 25, 2010 |
High Luminous Flux Warm White Solid State Lighting Device
Abstract
A high luminous flux warm white solid state lighting device with
a high color rendering is disclosed. The device comprising two
groups of semiconductor light emitting components to emit and
excite four narrow-band spectrums of lights at high luminous
efficacy, wherein the semiconductor light emitting components are
directly mounted on a thermal effective dissipation member; a
mixing cavity for blending the multi-spectrum of lights; a
back-transferred light recycling member deposited on top of an LED
driver and around the semiconductor light emitters; and a diffusive
member to diffuse the mixture of output light from the solid state
lighting device. The solid state lighting device produces a warm
white light with luminous efficacy at least 80 lumens per watt and
a color rendering index at least 85 for any lighting
application.
Inventors: |
Zhai; Jinhui; (Oldsmar,
FL) ; Morejon; Israel J.; (Tampa, FL) ; Bui;
Thong; (Tarpon Springs, FL) |
Correspondence
Address: |
HARVEY S. KAUGET;PHELPS DUNBAR, LLP
100 S. ASHLEY DRIVE, SUITE 1900
TAMPA
FL
33602-5311
US
|
Family ID: |
42239445 |
Appl. No.: |
12/834468 |
Filed: |
July 12, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12336107 |
Dec 16, 2008 |
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12834468 |
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Current U.S.
Class: |
257/89 ; 257/91;
257/98; 257/E33.056; 257/E33.061; 257/E33.067 |
Current CPC
Class: |
F21Y 2115/10 20160801;
F21V 9/02 20130101; F21V 3/00 20130101 |
Class at
Publication: |
257/89 ; 257/98;
257/91; 257/E33.056; 257/E33.061; 257/E33.067 |
International
Class: |
H01L 33/50 20100101
H01L033/50 |
Claims
1. A solid state lighting device comprising: a first group of
semiconductor light emitting components emitting a first spectrum
of primary light; a first wavelength down-conversion layer on top
of said first group of semiconductor light emitting components
exciting a second spectrum of yellow light having a narrow
bandwidth; a second wavelength down-conversion layer on top of said
first wavelength down-conversion layer exciting a third spectrum of
light having a peak wavelength between said first spectrum of
primary light and said second spectrum of yellow light; a second
group of semiconductor light emitting components emitting a fourth
spectrum of light having a peak wavelength longer than said first
spectrum of primary light and said second spectrum of yellow light;
a color mixing cavity having a diffusive output window mixing said
first spectrum of primary light, said second spectrum of yellow
light, said third spectrum of light and said fourth spectrum of
light; a light recycling reflector member around an interior wall
of said solid state lighting device, said light recycling reflector
member surrounding said first group of semiconductor light emitting
components and said second group of semiconductor light emitting
components; and a power line electrically connected to said first
group of semiconductor light emitting components and said second
group of semiconductor light emitting components.
2. The solid state lighting device according to claim 1, further
comprising: said first spectrum of primary light having a peak
wavelength range from about 440 nm to 465 nm; said second spectrum
of yellow light having a peak wavelength range from about 550 nm to
575 nm and a narrow bandwidth with full width at half maximum less
than 75 nm; said third spectrum of light having a peak wavelength
range from about 525 nm to 540 nm and a narrow bandwidth with full
width at half maximum less than 75 nm; and said fourth spectrum of
light having a peak wavelength range from about 610 nm to 620 nm
and a narrow bandwidth with full width at half maximum less than 25
nm.
3. The solid state lighting device according to claim 1, further
comprising: said first group of semiconductor light emitting
components emitting a near-UV primary light having a peak
wavelength range from about 380 nm to 420 nm; and said first
wavelength down-conversion layer comprising a mixture of blue
quantum dots, green quantum dots and yellow quantum dots, said
first wavelength down-conversion layer exciting a blue spectrum of
light having a peak wavelength from about 440 nm to 465 nm, a green
spectrum of light having a peak wavelength from about 525 nm to 540
nm and a yellow spectrum of light having a peak wavelength from
about 550 nm to 575 nm and a narrow bandwidth with full width at
half maximum less than 75 nm.
4. The solid state lighting device according to claim 1, wherein
said first group of semiconductor light emitting components further
comprising: a semiconductor light emitter emitting a spectrum of
primary blue light; a yellow wavelength conversion layer on top of
said semiconductor light emitter exciting a spectrum of yellow
light having a peak wavelength from about 550 nm to 575 nm and a
narrow bandwidth with full width at half maximum less than 75 nm;
and a green wavelength conversion layer on top of said yellow
wavelength conversion layer exciting a spectrum of green light
having a peak wavelength from about 525 nm to 540 nm.
5. The solid state lighting device according to claim 1, wherein
said second group of semiconductor light emitting components
further comprising a green semiconductor light emitter and a
reddish orange semiconductor light emitter emitting a spectrum of
yellow orange light, said green semiconductor light emitter and
said reddish orange semiconductor light emitter being packaged on a
single substrate chip.
6. The solid state lighting device according to claim 1, further
comprising: a body, said body having a side wall; said first group
of semiconductor light emitting components being packaged on said
side wall of said body; said second group of semiconductor light
emitting components being packaged on said side wall of said body;
and a reflective member positioned under said side wall of said
body.
7. The solid state lighting device according to claim 1, wherein
said diffusive output window further comprising a dome shape.
8. The solid state lighting device according to claim 1, further
comprising a wavelength conversion layer on top of said light
recycling reflector member.
9. A solid state lighting device comprising: a substrate; a first
group of semiconductor light emitting components being packaged on
a single light emitting device on said substrate, said first group
of semiconductor light emitting components emitting a first
spectrum of primary light; a first wavelength down-conversion layer
covering said first group of semiconductor light emitting
components and covering said substrate, said first wavelength
down-conversion layer exciting a second spectrum of yellow light
having a narrow bandwidth with full width at half maximum less than
75 nm; a second wavelength down-conversion layer on top of said
first wavelength down-conversion layer exciting a third spectrum of
light having a peak wavelength between said first spectrum of
primary light and said second spectrum of yellow light; a second
group of semiconductor light emitting components emitting a fourth
spectrum of light having a peak wavelength longer than said first
spectrum of primary light, said second spectrum of yellow light and
said third spectrum of light; a color mixing cavity having a
diffusive output window mixing said first spectrum of primary
light, said second spectrum of yellow light, said third spectrum of
light and said fourth spectrum of light; a light recycling
reflector member; and a power line electrically connected to said
first group of semiconductor light emitting components and said
second group of semiconductor light emitting components.
10. The solid state lighting device according to claim 9, further
comprising: said first spectrum of primary light having a peak
wavelength range from about 440 nm to 465 nm; said first wavelength
conversion layer and said second wavelength conversion layer having
YAG or Silicate based phosphor micro-particles; and said third
spectrum of light having a peak wavelength range from about 525 nm
to 540 nm and a narrow bandwidth with full width at half maximum
less than 75 nm; and said fourth spectrum of light having a peak
wavelength range from about 610 nm to 620 nm and a narrow bandwidth
with full width at half maximum less than 25 nm.
11. The solid state lighting device according to claim 9, wherein
said first wavelength conversion layer and said second wavelength
conversion layer further comprising a strontium calcium thiogallate
phosphor doped with divalent europium.
12. The solid state lighting device according to claim 9, wherein
said first wavelength conversion layer and said second wavelength
conversion layer further comprising a nanocrystal coating.
13. The solid state lighting device according to claim 9, further
comprising a reflective coating on top of said substrate.
14. The solid state lighting device according to claim 9, further
comprising a short-pass dichroic filter on top of said first group
of semiconductor light emitting components.
15. The solid state lighting device according to claim 9, further
comprising a transparent encapsulation resin between said first
wavelength down-conversion layer and said second wavelength
down-conversion layer.
16. The solid state lighting device according to claim 9, further
comprising a dome lens on top of said second wavelength
down-conversion layer.
17. A solid state lighting device comprising: a substrate; a group
of semiconductor light emitting components being packaged on a
single light emitting device on said substrate, said group of
semiconductor light emitting components emitting a short wavelength
first spectrum of primary light and a long wavelength second
spectrum of light; a first wavelength down-conversion layer
covering said group of semiconductor light emitting components and
covering said substrate, said first wavelength down-conversion
layer exciting a third spectrum of yellow light having a narrow
bandwidth; a second wavelength down-conversion layer on top of said
first wavelength down-conversion layer exciting a fourth spectrum
of light; a color mixing cavity having a diffusive output window
mixing said short wavelength first spectrum of primary light, said
long wavelength second spectrum of light, said third spectrum of
yellow light and said fourth spectrum of light; a light recycling
reflector member; and a power line electrically connected to said
group of semiconductor light emitting components.
18. The solid state lighting device according to claim 17, further
comprising: said short wavelength first spectrum of primary light
having a peak wavelength range from about 440 nm to 465 nm; said
long wavelength second spectrum of light having a peak wavelength
range from about 610 nm to 620 nm; said third spectrum of light
having a peak wavelength range from about 550 nm to 575 nm and a
narrow bandwidth with full width at half maximum less than 75 nm;
and said fourth spectrum of light having a peak wavelength range
from about 525 nm to 540 nm and a narrow bandwidth with full width
at half maximum less than 75 nm.
19. The solid state lighting device according to claim 17, further
comprising a reflective coating on top of said substrate.
20. The solid state lighting device according to claim 17, further
comprising a dome lens on top of said second wavelength conversion
layer.
Description
CROSS REFERENCES TO RELATED APPLICATIONS
[0001] This application is a divisional of commonly owned U.S.
Utility patent application Ser. No. 12/336,107, filed Dec. 16,
2008, entitled: High Luminous Flux Warm White Solid State Lighting
Device, this Utility patent application incorporated by reference
herein.
FIELD OF INVENTION
[0002] The invention relates generally to solid state lighting
devices, as well as related components, systems and methods, and
more particularly to methods to make warm white light with high
color rendering and high luminous efficacy.
BACKGROUND OF THE INVENTION
[0003] It is well known that incandescent light bulbs are very
energy inefficient light sources--about 90% of the electricity they
consume is released as heat rather than light. Fluorescent light
bulbs are by a factor of about 10 more efficient, but are still
less efficient than a solid state semiconductor emitter, such as
light emitting diodes, by a factor of about 2.
[0004] In addition, incandescent light bulbs have a relatively
short lifetime, i.e., typically about 750 to 1000 hours.
Fluorescent bulbs have a longer lifetime (e.g., 10,000 to 20,000
hours) than incandescent lights, but they contain mercury, not an
environment friendly light source, and they provide less favorable
color reproduction. In comparison, light emitting diodes have a
much longer lifetime (e.g., 50,000 to 75,000 hours). Furthermore,
solid state light emitters are very environmentally "green" light
sources and they can achieve very good color reproduction.
[0005] Accordingly, for these and other reasons, efforts have been
ongoing to develop solid state lighting devices to replace
incandescent light bulbs, fluorescent lights and other
light-generating devices in a wide variety of applications. In
addition, where light emitting diodes (or other solid state light
emitters) are already being used, efforts are ongoing to provide
improvement with respect to energy efficiency, color rendering
index (CRI Ra), luminous efficacy (lm/W), color temperature, and/or
duration of service, especially for indoor applications.
[0006] A semiconductor light emitting device utilizing a blue light
emitting diode having a main emission peak in blue wavelength range
from 400 nm to 490 nm, and a luminescent layer containing an
inorganic phosphor that absorbs blue light emitted by the blue LED
and produces an exciting light having an emission peak in a visible
wavelength range from green to yellow (in the range of about 525 nm
to 580 nm) with spectrum bandwidth (full width of half maximum,
simply refer to FWHM) about 80 to 100 nm.
[0007] Almost all the known light emitting semiconductor devices
utilizing blue LEDs and phosphors in combination to obtain
color-mixed light of the emission light from the blue LEDs and
excitation light from the phosphors use YAG-based or silicate-based
luminescent layer as phosphors. Those solid state lighting devices
have typically white color temperature about 5000 K to 8500 K with
low color rending index Ra about 60.about.70. This white solid
state lighting device is not desirable for some applications, like
indoor applications, which require warm white color about 2700 K to
3500 K with a high color rending index Ra above 80.
[0008] Known warm white semiconductor light emitting solutions and
their low luminous efficacy issues are shown at the followings:
1. Blue LED with mixture YAG-based or silicate-based phosphors (for
exciting yellow light) and nitrides or sulfides phosphors (for
exciting red light) for a warm white light. YAG-based or
silicate-based phosphors excite a broad-band yellow light having a
full spectrum range from 500 nm to 650 nm with FWHM about
80.about.100 nm. But this yellow excitation light has a shortage in
red and bluish green wavelength range, which limits its color
rendering index Ra less than 70. Adding a red phosphor to the
yellow phosphor can compensate for a shortage of red light,
resulting in improved color rendering index about 75.about.80. But
the red phosphor absorbs the emission blue light (with a peak
wavelength around 460 nm) and excites a red light (with a peak
wavelength around 620 nm), which causes a significant Stoke-shift
issue in photonic energy loss. Another issue with the mixture of
yellow and red phosphors is the broad-band spectrum distribution of
the excitation light, where luminous flux contribution is low at
two edge spectrums range due to the low sensitivity of red and
bluish green wavelength light to the human eye. 2. Blue LED with
mixture YAG-based or silicate phosphors (for exciting green light)
and nitrides or sulfides phosphors (for exciting orange light) for
a high color rendering warm white light. The mixture of green and
orange phosphors can compensate for the shortage of red light and
bluish green light, resulting in warm white with high color
rendering index above 80. But it has three issues which will cause
low luminous efficacy: a) multi-phosphors self-absorption loss of
the photons excited from the green and orange phosphor particles;
b) Stoked-shift loss from blue-to-red wavelength conversion; c) low
luminous flux contribution from the red and bluish green wavelength
in the broad-band spectrum distribution edge of the excitation
light. 3. Blue LED with YAG-based or silicate-based phosphors (for
exciting yellow light or blue shifting yellow light) and mixing
with a semiconductor emitting red/amber color light for a high
color rendering warm light. Adding red/amber semiconductor emitters
directly to the solid state white lighting device can solve the
issues of multi-phosphors self-absorption loss and Stokes shift
loss of the blue-to-red wavelength conversion. But it still suffers
from a low luminous flux contribution issue from the red and bluish
green wavelength range in the broad-band spectrum distribution of
the excitation light. And it still has a shortage of bluish green
wavelength. Besides this, more efforts are ongoing to improve the
light mixture from the multi-color semiconductor light
emitters.
BRIEF SUMMARY OF THE INVENTION
[0009] To overcome low luminous efficacy and low color reproduction
issues from the known warm white semiconductor light emitting
device. The present application discloses a system and a method of
a solid state lighting device to generate a high color rendering
warm white light at a high luminous efficacy. The solid state
lighting device includes a first group of semiconductor light
emitting components generating a mixture light of an emitted first
spectrum blue light and an excited second spectrum yellow light
having a narrow bandwidth; a second group of semiconductor light
emitting components emitting at least a third spectrum narrow-band
reddish orange light to compensate for the shortage of red
wavelength in the narrow-band yellow excitation light; a fourth
spectrum narrow-band green light either excited from the first
group of semiconductor light emitting components or emitted from
the second group of semiconductor light emitting components to
compensate for the shortage of bluish green wavelength in the
narrow-band yellow excitation light; a diffusive output window
member having an air space to the semiconductor light emitting
components to diffuse the first and second groups of the emission
lights; a back-transferred light recycling member to convert the
back-transferred light into a forward-transferred light; and a
light mixing cavity between the groups of the semiconductor light
emitting components, the back-transferred light recycling member
and the diffusive member for mixing the multi-spectrums lights. The
first and second groups of semiconductor light emitting components
directly mounted on a thermal effective dissipation member. If a
current is supplied to the power string line, a mixture of light
from the first and second groups of the semiconductor light
emitting components produce a high luminous flux warm white light
with luminous efficacy at least 80 lumens per watt and color
rendering index at least 85 for any indoor lighting
applications.
[0010] In one embodiment, the first group of the semiconductor
light emitting components generates a high luminous efficacy
sub-mixture of white light from an emitted blue light and an
excited yellow light with a peak wavelength of 550 nm.about.575 nm
and a spectrum width FWHM less than 75 nm. The chromaticity
coordinates of a sub-mixture of white light is closed to the
blackbody locus on 1931 CIE. The second group of semiconductor
light emitting components generates a sub-mixture of yellowish
orange light from the semiconductor reddish orange emitters and the
semiconductor green emitters, which all have state-of-art high
luminous efficacy. The second group of lights compensates for the
shortage of red and bluish green wavelength range in the first
group of narrow-band yellow excitation light. The mixture of the
first and second semiconductor emitting components produces a high
luminous flux warm white light with a high luminous efficacy, as
well as a high color rendering index.
[0011] In another embodiment, the first group of the semiconductor
light emitting components comprises a semiconductor blue light
emitter; a yellow phosphor layer to absorb blue light and excite a
yellow light with a spectrum width FWHM less than 75 nm; and a
green phosphor layer with a space to a yellow phosphor layer to
absorb the leakage blue light and convert it into a green light
with a spectrum width FWHM less than 75 nm. The sub-mixture of the
emitted blue light and excited yellow and green lights has
chromaticity coordinates above a blackbody locus on 1931 CIE at
improved luminous efficacy. The second group of the semiconductor
light emitting components has a semiconductor reddish orange
emitters with a state-of-art high luminous efficacy to compensate
for the shortage of red wavelength in the first group sub-mixture
of light. The mixture of the first and second semiconductor
emitting components produce a high luminous flux warm white light
with high luminous efficacy, as well as a high color rendering
index.
[0012] In another embodiment, the first group of the semiconductor
light emitting components includes at least one semiconductor light
emitter array in a single package having a high reflection coating
on the top surface of a substrate. A first phosphor layer deposited
on top of the reflective substrate to cover both the semiconductor
light array emitters and the space between the semiconductor light
array emitters to excite a second spectrum of yellow light with a
narrow bandwidth. A second phosphor layer on top of the first
phosphor layer to excite a third spectrum of green light from the
leakage of first spectrum light to improve its luminous
efficacy.
[0013] In another embodiment, a method of mixing the lights from
the two groups of the semiconductor light emitting components is
provided. The method includes a light mixing cavity between the
semiconductor light emitting components, the back-transferred light
recycling member and the light diffusive member. The
back-transferred light recycling member will convert the
backscattering light from the diffusive member and the
emission/excitation light from the semiconductor light emitting
components into a forward-transferred light and export from the
diffusive output window. The lights from the two groups of the
semiconductor light emitting components get completely mixed before
exporting through the diffusive output window of the solid state
lighting device.
[0014] In another embodiment, the back-transferred recycling member
includes a wavelength conversion layer. The wavelength conversion
layer will convert the emission of short wavelength light into a
desired visible wavelength to recycle the back-transferred light
and at same time to adjust the mixing light chromaticity.
[0015] The foregoing has outlined rather broadly the more pertinent
and important features of the present invention in order that the
detailed description of the invention that follows may be better
understood so that the present contribution to the art can be more
fully appreciated. Additional features of the invention will be
described hereinafter which form the subject of the claims of the
invention. It should be appreciated by those skilled in the art
that the conception and the specific embodiment disclosed may be
readily utilized as a basis for modifying or designing other
structures for carrying out the same purposes of the present
invention. It should also be realized by those skilled in the art
that such equivalent constructions do not depart from the spirit
and scope of the invention as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a cross sectional view of one embodiment of a
solid state lighting device according to the present invention;
[0017] FIG. 2 is a CIE 1931 diagram;
[0018] FIG. 3 is a cross sectional view of one embodiment of a
solid state lighting device according to the present invention;
[0019] FIG. 4 is a cross sectional view of one embodiment of a
solid state lighting device according to the present invention;
and
[0020] FIG. 5 is a cross sectional view of one embodiment of a
solid state lighting device according to the present invention.
[0021] Similar reference characters refer to similar parts
throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0022] An object of the present invention is to suppress certain
wavelength spectrums shortage, Stoke-shift loss of blue-to-red
wavelength conversion, multi-phosphors absorption loss and radiance
power loss at red/bluish green tail range of a broad-band excited
yellow light in a warm white solid state lighting device by
utilizing a narrow-band excited yellow light mixing with
semiconductor emitting yellowish orange light, in combination with
a forth spectrum green light in a mixing cavity so as to provide a
solid state lighting device or solid state lighting system in warm
white color temperature range exhibiting a luminous flux higher
than known white-light emitting semiconductor devices and a high
color rendering index above 85.
The First Aspect of the Present Invention
[0023] According to the first aspect of the present invention as
shown in FIG. 1, a solid state lighting device 10 comprising a
first group of semiconductor light emitting components 20; a second
group of semiconductor light emitting components 30; a single power
string line 90; a back-transferred recycling member 60; a diffusive
member 40 and a mixing cavity 45 formed inside of the above
members.
[0024] The first group of semiconductor light emitting components
20 generate a high luminous efficacy sub-mixture of white light.
The first group of semiconductor light emitting components 20
includes at least one semiconductor light emitter 80 for a first
spectrum short wavelength light 120 and at least one
down-conversion phosphor layer 100 on top of the semiconductor
light emitter 80 for exciting a second spectrum of yellow light 130
with a narrow bandwidth. Wherein, the spectral emission of the
first spectrum light 120 has a peak wavelength range from 440
nm.about.465 nm; the spectral emission of the second spectrum light
130 has a peak wavelength range from 550 nm.about.575 nm at a
spectrum width FWHM less than 75 nm. In this excited narrow-band
yellow light spectrum distribution, the bluish green tail
wavelength range from 500 nm.about.520 nm and red tail wavelength
range from 620 nm.about.650 nm have been significantly cut-off to
reduce photons energy loss at these human eye less sensitivity
spectrums range.
[0025] The second group of semiconductor light emitting components
30 generate at least a third spectrum of reddish orange light 140.
The spectral emission of the third spectrum light 140 has a peak
wavelength range from 610 nm.about.620 nm with FWHM less than 25
nm. The second group of emitted reddish orange light 140 will
compensate for the shortage of bluish green light in the first
group of yellow excite light 130.
[0026] A fourth spectrum of green light 150 either exciting from
the first group of semiconductor light emitting components 20 or
emitting from the second group of semiconductor light emitting
components 30. The spectral emission of the fourth spectrum of
light 150 has a peak wavelength range from 525 nm.about.535 nm. The
fourth spectrum of green light 150 will compensate for the shortage
of bluish green light in the first group of yellow excited light
130.
[0027] A dome lens 75 from a high refractive index above 1.5 may be
deposited on top of each semiconductor light emitter to reduce
total internal reflection loss.
[0028] The single power string line 90 electrically connects each
of the first group of semiconductor light emitting components 20
and each of the second group of semiconductor light emitting
components 30.
[0029] A light mixing cavity 45 is formed inside of the
semiconductor light emitting components (LEDs), the LED driver
board 55 and the diffusive output window 40. The diffusive output
window 40 having an air space to the semiconductor light emitting
components 20, 30. A back-transferred recycling member 60 is
deposited inside the light mixing cavity 45 on top of the LED
driver board 55 and around the semiconductor light emitting
components 20, 30 to convert back-transferred light into a
forward-transferred light and exported from the diffusive output
window 40.
[0030] If a current is supplied to the power string line 90, a
combination of the first spectrum light 120 and the second spectrum
light 130 emitting from the first group of semiconductor light
emitting components 20, in an absence of any additional light,
produce a sub-mixture of white light with corrected color
temperature (CCT) in a 4500 K.about.6000 K range and a luminous
efficacy greater than 90 lm/W; a combination of the third spectrum
light 140 and the fourth spectrum light 150, in an absence of any
additional light, produce a sub-mixture of yellowish orange light
with a luminous efficacy greater than 90 lm/W; and a combination of
1) Light producing from the first group of semiconductor light
emitting components 20, and 2) Light producing from the second
group of semiconductor light emitting components 30 produces a
mixture of warm white light within ten MacAdam ellipses with at
least one point on a blackbody locus, as shown in FIG. 2, having a
correct color temperature in a 2700 K.about.3500 K range with a
color rendering index (CRI) at least 85.
[0031] In some embodiments according to the first aspect of the
present invention, the solid state lighting device 10 may comprise
the first spectrum light 120 and the second spectrum light 130 from
the first group of semiconductor light emitting components 20,
producing a mixture of light having (x,y) coordinates on 1931 CIE
within an area enclosed by four line segments having (x,y)
coordinates (0.325,0.310), (0.360,0.330), (0.370,0.400), and
(0.320,0.390); and the third spectrum light 140 and the fourth
spectrum light 150 from the second group of semiconductor light
emitting components 30, producing a mixture of light having (x,y)
coordinates on 1931 CIE within an area enclosed by four line
segments having (x,y) coordinates (0.500,0.450), (0.525,0.465),
(0.565,0.425), and (0.520,0.420);
[0032] In some embodiments according to the first aspect of the
present invention, the solid state lighting device 10 may comprise
semiconductor light emitting components 20 (LEDs) directly packaged
on a thermal effective dissipation member 160.
[0033] As shown in FIG. 5, in some embodiments according to the
first aspect of the present invention, the solid state lighting
device 10 may comprise semiconductor light emitting components 20
(LEDs) directly packaged on the side wall 67 of the solid state
lighting device body 65 for thermal effective dissipation and have
a reflective member 70 to redirect light into a forward-transferred
light and mixed at the mixing cavity 45 before exported from the
diffusive output window 40.
[0034] In some embodiments according to the first aspect of the
present invention, the solid state lighting device 10 may comprise
a back-transferred light recycling component 60 including a
wavelength conversion component 50. The wavelength conversion
component 50 is deposited on top of the back-transferred recycling
member 60. The wavelength conversion component 50 absorbs
backscattering short wavelength light from the diffusive member 40
and emission light from the semiconductor emitting components 20,
and converts it into desired visible light to adjust the mixing
light chromaticity.
[0035] In some embodiments according to the first aspect of the
present invention, the phosphor layer in the first group of
semiconductor light emitting components 20 may be quantum dots,
exciting a yellow light with a narrow bandwidth of FWHM less than
75 nm.
[0036] In some embodiments according to the first aspect of the
present invention, the first group of semiconductor light emitting
components 20 may include at least one semiconductor emitter 80 for
emitting a first spectrum of blue or near UV light; at least a
first phosphor layer 100 on top of the semiconductor emitter 80
excited by the first spectrum light 120 and produce a second
spectrum of yellow light 130; at least a second phosphor layer 110
on top of the first phosphor layer 100 excited by the leakage from
the first spectrum of light 120 and produces a forth spectrum of
green light 150. It may have a transparent dome lens 75 deposited
between the first phosphor layer 100 and the second phosphor layer
110.
[0037] In some embodiments according to the first aspect of the
present invention, the first group of semiconductor light emitting
components 20 may include a semiconductor emitter 80 for emitting
near-UV exciting light in a center wavelength range 380
nm.about.420 nm and at least two quantum dots to absorb the near-UV
exciting light and produce a first spectrum of blue light 120 and a
second spectrum of yellow light 130.
[0038] In some embodiments according to the first aspect of the
present invention, the second group of semiconductor light emitting
components 30 may include a green semiconductor light emitter and a
reddish orange semiconductor emitter. The green semiconductor light
emitter and the reddish orange semiconductor light emitter are
packaged on a single substrate chip 70. A high refractive index
dome lens is used to encapsulate the co-package dies. The green and
reddish orange light are mixed in the encapsulation resin to
produce a mixture of yellowish orange light.
[0039] In some embodiments according to the first aspect of the
present invention, the second group of solid state light components
30 may include a green semiconductor emitter and a phosphor excited
by the green light to emit a reddish orange light. A combination of
the emitted green light and the excited reddish orange light
produce a mixture of light having (x,y) coordinates on 1931 CIE
within an area enclosed by four line segments having (x,y)
coordinates (0.500,0.450), (0.525,0.465), (0.565,0.425), and
(0.520,0.420).
The Second Aspect of the Present Invention
[0040] According to the second aspect of the present invention as
shown in FIG. 3, a solid state lighting device comprising a first
group of semiconductor light emitting components 20 in a single
package; a second group of semiconductor light emitting components
30; a single power string line 90; a back-transferred recycling
member 60; a diffusive member 40 and a mixing cavity 45 formed
inside of the above members.
[0041] The first group of semiconductor light emitting components
20 include a semiconductor light emitter array 80 packaged on a
single substrate 70 having a high reflection coating on the top
surface to produce a first spectrum of short wavelength light 120;
a first phosphor layer 100 deposited on top of the reflective
substrate 70 to cover the entire substrate along with the first
group of semiconductor light emitting components 20 and the second
group of semiconductor light emitting components 30 to excite a
second spectrum of yellow light 130 with a narrow bandwidth; and at
least a second phosphor layer 110 on top of the first phosphor
layer 100 to excite a third spectrum of green light 140 from the
leakage of the first spectrum light 120 to improve its luminous
efficacy.
[0042] In a addition, a short-pass dichroic filter can be placed on
top of said first group of semiconductor light emitting
components.
[0043] The second group of semiconductor light emitting components
30 generates at least a fourth spectrum of reddish orange light 150
to compensate for the shortage of red wavelength in first group of
excited yellow light.
[0044] The single power string line 90 electrically connects to
each of the first group of semiconductor light emitting components
20 and each of the second group of semiconductor light emitting
components 30.
[0045] A light mixing cavity 45 is formed inside of the
semiconductor light emitting components 20, 30 (LEDs), the LED
driver board 55 and the diffusive output window 40. The diffusive
output window 40 having an air space to the semiconductor light
emitting components 20, 30. A back-transferred recycling member 60
is deposited inside the light mixing cavity 45 on top of the LED
driver board 55 and around the semiconductor light emitting
components 20, 30 to convert back-transferred light into a
forward-transferred light and exports the light from the diffusive
output window 40.
[0046] Wherein, the spectral emission of the first spectrum of
light 120 from the first group of semiconductor light emitting
components 20 has a center wavelength range from 440 nm.about.465
nm; the spectral emission of the second spectrum of light 130 from
the first group of semiconductor light emitting components 20 has a
center wavelength range from 550.about.575 nm with FWHM less than
75 nm; the spectral emission of the third spectrum of light 140
from the first group of semiconductor light emitting components 20
has a center wavelength range from 525 nm.about.540 nm with FWHM
less than 75 nm; and the spectral emission of the fourth spectrum
of light 150 from said second group of semiconductor light emitting
components 30 has a center wavelength range from 610 nm.about.620
nm with FWHM less than 25 nm. In the narrow-band of exciting yellow
light, the bluish green tail wavelength range from 500 nm.about.520
nm and red tail wavelength range from 620 nm.about.650 nm have been
significantly cut-off to reduce photons energy loss of the excited
yellow light at these human eye less sensitivity spectrums range.
The narrow-band of yellow excitation light and additional green
phosphor on top of the yellow phosphor will enhance the luminous
efficacy of the sub-mixture of greenish white light.
[0047] If a current is supplied to the power string line 90, the
first spectrum emission of light 120, second spectrum of excitation
light 130 and third spectrum of excitation light 140 from the first
group of semiconductor light emitting components 20, produces a
mixture of light having (x,y) coordinates on 1931 CIE within an
area enclosed by four line segments having (x,y) coordinates
(0.325,0.310), (0.360,0.330), (0.370,0.400), and (0.320,0.390) with
an enhanced luminous efficacy at least 90 lm/W; and a combination
of 1) Light produced from the first group of solid state lighting
components 20, and 2) Light produced from the second group of solid
state lighting components 30 produces a mixture of light within ten
MacAdam ellipses with at least one point on a blackbody locus,
having a correct color temperature in a 2700 K.about.3500 K range
with a color rendering index (CRI) at least 85.
[0048] In some embodiments according to the second aspect of the
present invention, the first group of semiconductor light emitting
components 20 include a semiconductor light emitter array 80 for
emitting blue light in a center wavelength range of 450
nm.about.465 nm.
[0049] In some embodiments according to the second aspect of the
present invention, the first group of semiconductor light emitting
components 20 include a semiconductor light emitter array 80 for
emitting near UV light in a center wavelength range of 380
nm.about.420 nm.
[0050] In some embodiments according to the second aspect of the
present invention, the first group of the semiconductor light
emitting components 20 include a dome 75 from a high refractive
index resin deposited on top of the second phosphor layer 110 to
reduce total internal reflection loss.
The Third Aspect of the Present Invention
[0051] According to the third aspect of the present invention as
shown in FIG. 4, a solid state lighting device 10 comprising a
group of semiconductor light emitting components 20 including a
semiconductor light emitter array 80 having more than one emission
light spectrum; one single power string line 90; one
back-transferred recycling member 60; one diffusive member 40 and a
mixing cavity 45 formed inside of the above members.
[0052] The semiconductor light emitter array 80 includes a
semiconductor blue light emitter and a semiconductor reddish orange
light emitter; a first phosphor layer 100 covering all of the
semiconductor light array emitters 80 and the space between the
semiconductor light array emitters to excite a third spectrum of
yellow light; and at least a second phosphor layer 110 on top of
the first phosphor layer 100 to excite a fourth spectrum of green
light from the leakage blue light.
[0053] If a current is supplied to the power string line 90, a
combination of a first spectrum of emitted blue light 120, a second
spectrum of emitted reddish orange light 130, a third spectrum of
excited yellow light 140 from the leakage blue light, and a forth
spectrum of excited green light 150 from the leakage blue light
produces a mixture of light within ten MacAdam ellipses with at
least one point on a blackbody locus, having a correct color
temperature in a 2700 K 3500 K range with a color rendering index
(CRI) at least 85, as well as a high luminous efficacy at least 90
lm/W.
[0054] In some embodiments according to the third aspect of the
present invention, the first group of the semiconductor light
emitting components 20 includes a dome lens 75 from a high
refractive index resin deposited on top of the second phosphor
layer 110 to reduce total internal reflection loss.
[0055] It is understood that the above description is intended to
be illustrative and not restrictive. Although various
characteristics and advantages of certain embodiments of the
present invention have been highlighted herein, many other
embodiments will be apparent to those skilled in the art without
deviating from the scope and spirit of the invention disclosed. The
scope of the invention should therefore be determined with
reference to the claims contained herewith as well as the full
scope of equivalents to which said claims are entitled.
[0056] Now that the invention has been described,
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