The University of Danang - Journal of Science and Technology,
Journal Year:
2024,
Volume and Issue:
unknown, P. 53 - 57
Published: March 31, 2024
The
light-emitting
diodes
(LEDs)
have
emerged
as
a
sustainable
illumination
solution
in
the
lighting
industry.
However,
commercial
LEDs
suffer
from
low
chromatic
rendition
performance.
This
work
proposes
feasible
approach
to
enhance
quality
of
LED
packages
via
regulating
scattering
factors.
TiO2
nano
particles
are
added
into
YAG:Ce3+
compound
internal
performance,
inducing
blue-light
conversion
and
extraction.
In
this
work,
concentration
varies
0
wt%
20
wt%.
Results
show
that
5
is
right
achieve
optimal
performance
for
improvements
luminosity
color
LED.
If
beyond
wt%,
these
two
parameters
decline
owing
too
intensive
light
scattering.
Meanwhile,
10
most
appropriate
uniformity
Abstract
Laser‐driven
white
light
exhibits
exceptional
brightness
and
directionality,
making
it
particularly
well‐suited
for
spotlight
applications.
Yet,
attaining
high‐quality
remains
challenging
due
to
the
sluggish
heat
dispersion
inconsistent
uniformity
of
color
converters.
In
this
study,
an
innovative
phosphor‐in‐glass
(PiG)
film
architecture
is
introduced,
aiming
achieve
superior
quality
laser‐driven
light,
where
traditional
Y
3
(Ga,Al)
5
O
12
:Ce
3+
(YAGG:Ce
)
PiG
topped
with
a
Al
2
‐in‐glass
(AiG)
film.
The
heightened
thermal
conductivity
AiG
facilitates
quicker
dissipation
heat,
consequently
elevating
luminescence
saturation
threshold
from
14
16
W
mm
−2
luminous
flux
1243.8
1475.9
lm.
increased
scattering
attributed
also
effectively
disperses
both
laser
emitted
significantly
enhancing
angular
consistency
rendering
index
(Ra).
This
improvement
evident
as
coefficient
variation
(C
v
decreases
dramatically
16.69%
0.25%.
Moreover,
by
integrating
CaAlSiN
:Eu
2+
(CASN:Eu
into
fine‐tuning
YAGG:Ce
CASN:Eu
ratio,
achieving
impressive
(Ra)
88.7
offering
adjustable
correlated
temperature
(CCT)
has
been
developed.
innovation
holds
tremendous
potential
versatile
solution
indoor
outdoor
settings.
Advanced Materials,
Journal Year:
2024,
Volume and Issue:
36(14)
Published: Jan. 4, 2024
Laser-diode-based
solid-state
lighting
is
primarily
used
in
state-of-the-art
illumination
systems.
However,
these
systems
rely
on
light-converting
inorganic
phosphors,
which
have
low
quantum
efficiencies
and
complex
manufacturing
conditions.
In
this
study,
a
mismatched
refractive
index
strategy
proposed
to
directly
convert
natural
bulk
wood
into
laser-driven
diffuser
using
simple
delignification
polymer
infiltration
method.
The
resulting
material
has
the
potential
be
diffuse
applications.
optical
performance
of
optimized
by
changing
density
wood.
optimal
coefficient
illuminance
variation
as
17.7%,
significantly
lower
than
that
commercial
diffusers.
uniformity
larger
0.9,
higher
ISO
requirements
for
indoor
workplace
lighting.
laser
damage
threshold
7.9
J
cm
Journal of Materials Chemistry C,
Journal Year:
2024,
Volume and Issue:
12(17), P. 6046 - 6055
Published: Jan. 1, 2024
“Heavy
atom
substitution”
was
utilized
to
improve
the
thermal
behaviors
of
Ce:LuAG
transparent
ceramics
via
Sr
2+
/Si
4+
doping,
exhibiting
high
luminous
efficiency
radiation
(261.98
lm
W
−1
)
and
luminance
saturation
threshold
(∼65
mm
−2
).
Optics Express,
Journal Year:
2023,
Volume and Issue:
31(15), P. 24914 - 24914
Published: June 8, 2023
Ceramic
phosphors
are
widely
considered
the
next-generation
phosphor
material
for
white
LED/LD
lighting,
and
a
wide
spectrum
is
key
factor
in
improving
CRI
of
lighting
sources.
In
this
paper,
novel,
to
our
knowledge,
barcode-structured
YAG:Ce/YAG:Ce,Mn
ceramic
was
designed
fabricated.
The
sources
with
value
73.5
68.9
were
obtained
under
excitation
blue
LEDs
LDs,
respectively.
Simultaneously,
thanks
effective
supplementary
emission
from
red
LD,
ceramic-based
source
reached
81.8
LD
excitation.
Specifically,
microstructure
luminescent
property
different
thicknesses
ion
doping
concentrations
systematically
studied.
Besides,
by
changing
power
0.52
W
2.60
W,
CCT
laser
encapsulation
optimized
ranged
3928
K
5895
K,
while
always
maintained
above
80.
results
indicate
that
Ce:YAG/Ce,MnYAG
candidate
achieve
high
ican
be
applied
various
occasions.
Due
to
their
ease
of
fabrication
and
extremely
high
stability,
Al2O3-based
YAG:Ce
PiG
composite
films
have
been
widely
recognized
as
ideal
color
converters
in
laser
illumination.
However,
due
the
limitation
thermal
conductivity
Al2O3,
pump
utilization
rate
is
low
efficient
white
light
output
difficult
obtain
on
film.
Here,
we
present
a
illumination
component
using
porous
stainless
steel
loaded
YAG:Ce/glass
(PGiPSS),
which
sintered
at
800°C.
Owing
acceptable
ability
accommodate
numerous
luminescent
particles
pores,
PGiPSS
exhibits
quantum
efficiency
quenching
characteristics.
Impressively,
when
irradiated
by
450
nm
diode
with
maximum
excitation
power
density
24.10
W/mm2,
prepared
produced
correlated
temperature
(CCT)
6629
K
luminous
232
lm/W.
These
results
prove
that
suitable
for
high-power,
high-brightness
Journal of the American Ceramic Society,
Journal Year:
2023,
Volume and Issue:
106(10), P. 5933 - 5943
Published: June 7, 2023
Abstract
In
this
work,
a
series
of
Al
2
O
3
–Ce:YAG
phosphor
powders
were
synthesized
by
regulating
the
excess
3+
(Y,Ce)
5
12
via
coprecipitation
method
for
first
time,
where
,
Ce
and
Y
elements
uniformly
distributed.
With
increase
content,
morphology
changed
from
wormlike
shapes
to
flaky
shapes,
phases
had
tendency
convert
YAlO
phases.
The
x
wt.%
–(Y
0.999
0.001
)
(
=
20,
30,
40,
50,
60,
70)
composite
ceramics
(CPCs)
obtained
vacuum
sintering
(1775°C
×
10
h),
Ce:YAG
also
well‐distributed.
When
content
was
30–40
wt.%,
average
grain
size
close
that
Ce:YAG.
A
solid‐state
laser
lighting
device
constructed
450
nm
source
CPCs
in
reflection
mode.
By
adjusting
power,
correlated
color
temperature
(CCT)
values
white
diodes
(LDs)
achieved
standard
light
6500
K.
Impressively,
LDs
equipped
with
40
‐containing
showed
optimum
CCT
6498
K
(color
coordinates:
0.31
0.38),
as
well
high
luminous
flux
1169
lm
efficiency
166
lm/W
at
LD
power
7.05
W.
This
work
has
provided
potential
idea
optimize
composition
uniformity
explore
their
excellent
performance
application
lighting.
Optics Express,
Journal Year:
2023,
Volume and Issue:
31(25), P. 41556 - 41556
Published: Nov. 13, 2023
The
realization
of
high
front
light
emission
in
laser
lighting
under
transmissive
modes
is
heavily
constrained
by
low
thermal
stability
and
extraction
efficiency
color
converter
materials.
Therefore,
it
necessary
to
improve
the
heat
dissipation
capacity
utilization
through
appropriate
microstructural
adjustments.
In
this
study,
what
we
believe
be
a
novel
laminated
structure
consisting
Al2O3
YAG:Ce
was
designed
fabricated
for
lighting.
Through
design,
possible
change
phosphor
angle,
overcoming
limitations
total
internal
reflection
enabling
maximal
yellow
from
ceramic
surface.
This
enhanced
24.4%
compared
composite
phosphor.
addition,
conduction
area
between
layer
have
been
effectively
enhanced.
Ultimately,
high-power
density
47.6
W/mm2,
all
ceramics
showed
no
luminous
saturation
threshold.
A
high-brightness
with
flux
651
lm,
144
lm/W,
correlated
temperature
6419
K
operating
as
84.9
°C
obtained.
These
results
suggest
that
structural
Al2O3/YAG:Ce
promising
candidate
mode
