Download LIGHT EMITTING DIODE, BACKLIGHT UNIT AND LIQUID CRYSTAL

LIGHT EMITTING DIODE, BACKLIGHT UNIT AND LIQUID CRYSTAL DISPLAY
HAVING THE SAME
BACKGROUND OF THE INVENTION
5
1.
Field of the Invention
The invention relates to a light emitting diode, and a
backlight unit and a liquid crystal displaying unit having
the same.
In particular, the present invention relates to a
light emitting diode with improved coloring mixing, and a
10
backlight unit and a liquid crystal displaying unit having
the same.
2.
Description of the Related Art
Light bulbs, light emitting diodes (LED), fluorescent
lights and metal halide lamps are generally used as light
15
sources of backlight units of liquid crystal displaying units.
Recently, backlight units that use light emitting diodes,
which can achieve low electricity consumption, light weight
and compactness better than the back light units that use
conventional cold cathode fluorescent light (CCFL), are being
20
developed.
A backlight unit using the light emitting diodes
uses as a light source unit a light emitting diode array in
which a plurality of light emitting diodes is arranged on a
printed circuit board in a row or in a matrix pattern.
It is possible to use both a multi-chip light emitting
25
diode which has a plurality of light emitting chips in a single
1
package and a single-chip light emitting diode which has one
light emitting chip in a single package.
A multi-chip light emitting diode packs a light emitting
chip with two or more colors in a single package, and a molding
5
part is formed on top of it.
The multi-chip light emitting
diode, compared to the single-chip light emitting diode, is
advantageous
in
color
mixing.
More
particularly,
the
multi-chip light emitting diode is relatively better than the
single-chip light emitting diode in color mixing, but, when
10
compared to other types of light source used as backlights,
the color mixing property of the multi-chip light emitting
diode lacks behind.
SUMMARY OF THE INVENTION
15
Accordingly, the present invention has been finalized in
order to solve the above-described problems, and it is an object
of the invention to provide a light emitting diode with improved
color mixing and a backlight unit and a liquid crystal display
having the same.
20
An aspect of the invention provides a light emitting diode
which includes: a substrate in which a reflective part is formed
in a recessed shape; and at least one light emitting chip that
is mounted on the reflective part of the substrate.
The
reflective part is composed of a base surface, a side wall that
25
is formed to incline at a first angle with respect to the base
2
surface, and the light emitting chip is mounted on the side wall.
A plurality of the light emitting chips is mounted on the
side wall at predetermined intervals.
The plurality of light emitting chips is mounted on the
5
side wall at equal intervals.
The first angle is in the range of 120 to 150 degrees.
The light emitting diode further includes a protrusion
formed on the base surface.
The protrusion is formed to have height equal to or smaller
10
than depth of the reflective part.
The protrusion includes a reflective surface that is
formed to incline at a second angle with respect to the base
surface.
The second angle is in the range of 5 to 85 degrees.
15
The protrusion
is formed in a
conical shape
or a
polypyramid shape.
The light emitting chip includes at least one of a red light
emitting chip, a green light emitting chip and a blue light
emitting chip.
20
The light emitting chip includes a white light emitting
chip.
The light emitting diode further includes a lead terminal
and a wire to apply power to the light emitting chip.
The light emitting diode further includes a molding part
25
to cap the light emitting chip.
3
The base surface is formed in a circular shape, a polygon
shape, and a polygon shape including curves.
Another aspect of the invention provides backlight unit
which includes: a light emitting diode including a substrate
5
in which a reflective part is formed in a recessed shape and
a plurality of light emitting chips mounted on the reflective
part of the substrate, in which the reflective part is composed
of a base surface and a side wall that is formed to incline at
a first angle with respect to the base surface, and the plurality
10
of light emitting chips are mounted on the side wall; and a light
source unit including a printed circuit board on which the light
emitting diode is mounted.
The backlight unit further includes a protrusion that is
formed to incline at a second angle with respect to the base
15
surface.
Another aspect of the invention provides a backlight unit
which includes: a light emitting diode including a substrate
in which a reflective part is formed in a recessed shape and
a single light emitting chip mounted on the reflective part of
20
the substrate, in which the reflective part is composed of a
base surface and a side wall that is formed to incline at a first
angle with respect to the base surface, and the single light
emitting chip is mounted on the side wall; and a light source
unit including a printed circuit board on which a plurality of
25
the light emitting diodes are mounted, in which the plurality
4
of light emitting diodes are divided into light emitting diode
units each composed of two or more light emitting diodes so as
to be mounted on the printed circuit board.
The backlight unit further includes a protrusion having
5
a reflective surface that is formed to incline at a second angle
with respect to the base surface.
Another aspect of the invention provides a liquid crystal
display which includes: a backlight unit which has the
above-described aspects; and a liquid crystal display panel
10
disposed on the backlight unit to display image.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features and advantages of the present
invention will become more apparent by describing in detail
15
preferred embodiments thereof with reference to the attached
drawings in which:
FIG. 1 is a perspective view of a light emitting diode
according to an embodiment of the present invention;
FIGS. 2a and 2b are a layout view of the light emitting
20
diode of FIG.1 and a cross-sectional view of the light emitting
diode;
FIGS. 3a and 3b are views of modifications of the light
emitting diode of FIG. 1;
FIGS.
25
4a
and
4b
are
a
perspective
view
and
a
cross-sectional view of a light emitting diode according to a
5
conventional art;
FIGS. 5a and 5b are a result diagram of light distribution
and a chroma data of the light emitting diode according to the
conventional art and the embodiment of the present invention;
5
FIG. 6 is a table comparing the level of color mixing of
the light emitting diode between the conventional art and the
embodiment of the present invention;
FIGS. 7 and 8 are a perspective view and a cross-sectional
view of the light emitting diode according to a second
10
embodiment of the present invention;
FIG. 9 is a draft schematically illustrating the light
emitting diode shown in FIGS. 7 and 8;
FIGS. 10a to 10e are modifications of the light emitting
diode shown in FIGS. 7 and 8;
15
FIG. 11 is a table comparing the level of color mixing of
the light emitting diode between the conventional art and the
modifications of FIGS. 10a to 10e;
FIGS. 12a to 12e are other modifications of the light
emitting diode shown in FIGS. 7 and 8;
20
FIG. 13 a table comparing the level of color mixing of the
light emitting diode between the conventional art and the
modifications of FIGS. 12a to 12e;
FIGS. 14a and 14b are a plan view and a perspective view
of the light emitting diode according to a third embodiment of
25
the present invention; and
6
FIGS. 15 and 16 are an exploded perspective views
illustrating one or other example of a liquid crystal display
including a backlight composed of the light emitting diodes
according to the present invention.
5
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter,
embodiments
of
the
invention
will
be
described in detail with reference to the accompanying drawings.
The present invention may, however, be embodied in many
10
different forms and should not be construed as being limited
to the embodiments set forth herein.
Rather, these embodiments
are provided such that this disclosure will be thorough and
complete and will fully convey the concept of the invention to
those skilled in the art.
15
Hereinafter,
preferred
embodiments
of
the
present
invention will be described in detail with reference to the
accompanying drawings.
FIG. 1 is a perspective view of a light emitting diode
according to an embodiment of the present invention.
20
FIGS. 2a
and 2b are a layout view of the light emitting diode of FIG.1
and a cross-sectional view of the light emitting diode.
With reference to FIGS. 1 to 2b, a light emitting diode
410 according to the embodiment of the present invention
includes a substrate 411, a light emitting chip 412, a lead
25
terminal 413, a wire 414, a reflective part 415 and a molding
7
part 419.
The reflective part 415 is formed in a recessed shape on
a first surface of the substrate 411, that is, an upper side
of the substrate.
5
The reflective part 415 is parallel to the
first surface of the substrate 411, and composed of a base
surface 416 that is formed to have a predetermined recessed
depth, and a side wall 417 that is formed to incline at a first
angle θ1 with respect to the base surface 416.
In this case,
the base surface 416 is formed in a circular shape.
10
The light emitting chip 412 is mounted on the side wall
417 of the reflective part 415 so as to be inclined at the first
angle θ1 with respect to the base surface 416.
At this time,
the light emitting chip 412 includes first to fourth light
emitting chips 412a to 412d, the light emitting chips 412a to
15
412d are mounted at predetermined intervals on the side wall.
According to the embodiment, the light emitting chips 412a to
412d are mounted at uniform intervals, but not limited thereto.
In addition, the first light emitting chip 412a is a blue light
emitting chip which emits blue light, the second light emitting
20
chip 412b is a green light emitting chip which emits green light,
the third light emitting chip 412c is a red light emitting chip
which emits red light, and the fourth light emitting chip 412d
is a green light emitting chip which emits green light.
Otherwise, the first to fourth light emitting chips 412a to 412d
25
may be white light emitting chips emitting white light.
8
In
other words, the light emitting chip 412 can emit light with
various wavelengths.
To enable this, for example, the amount
of indium (In) that is used as an active layer in a nitride based
light emitting diode is controlled, or light emitting diodes
5
emitting light with different wavelengths are mixed, or a light
emitting chip emitting light at a predetermined wavelength band,
like ultraviolet rays, is combined with fluorescent substance.
The number and type of the light emitting chips used in the
present embodiment and the mounting intervals between the light
10
emitting chips are illustrative and can be modified in many
different forms.
The first angle θ1 at which the light emitting chip 412
is inclined with respect to the base surface 416 can be
controlled with and the range of 120 to 150 degrees.
15
In the
present embodiment, the first angle θ1 is 135 degrees.
The lead terminal 413 that is composed of a first lead
terminal 413a and a second lead terminal 413b is disposed to
the substrate 411.
One end of the lead terminal 413 is disposed
on the base surface 416 to be exposed; the other end is bent
20
along the side wall of the substrate so as to be disposed on
a second surface of the substrate 411, that is, the lower side.
Unlike this, the other end of the lead terminal 413 can extend
to the outside of the substrate 411.
The wire 414 is connected to the light emitting chip 412,
25
the first lead terminal 413a and the second lead terminal 413b.
9
When an exterior power source supplies power to the first lead
terminal 413a and the second lead terminal 413b, the power is
supplied through the wire 414 to a P electrode (not shown) and
an N electrode (not shown) of the light emitting chip 412, and
5
the light emitting chip 412 emits light of a predetermined
wavelength.
The molding part 419 is formed on the substrate 411 to cap
the light emitting chip 412 and the wire 414.
In this case,
the molding part 419 may be formed in an optical lens shape,
10
a flat shape, etc.
In the present embodiment, the molding part
is formed in a semicircular shape or a dome shape.
The molding
part 419 is made of transparent resin, such as liquid epoxy resin
or silicon resin.
The molding part 419 may have fluorescent
substance (not shown) mixed therein to absorb light emitted from
15
the light emitting chip 412 and convert the light into
wavelength.
FIGS. 3a and 3b are views of modifications of the light
emitting diode of FIG. 1.
In FIGS. 3a and 3b, the lead terminal
and the wire are not illustrated, and the same components as
20
those of FIG. 1 are denoted by the same reference numerals, and
the
description
thereof
will
be
omitted
and
different
constitution from that of FIG. 1 will be mainly described.
Referring to FIG. 3a, a light emitting diode 420 includes
a substrate 421, light emitting chips 422, a lead terminals (not
25
shown), wires (not shown), a reflective part 425 and a molding
10
part 429.
The reflective part 425 is formed in a recessed shape on
the upper side of the substrate 421.
The reflective part 425
is parallel to the upper side of the substrate 421, and composed
5
of a base surface 426 that is formed to have a predetermined
recessed depth, and a side wall 427 that is formed to incline
at a predetermined angle with respect to the base surface 426.
In this case, the base surface 426 is formed in a polygon shape,
for example, an octagon.
10
The side wall 427 that extends from
the base surface 426 are composed eight side walls, and each
of the side walls is formed of a flat surface, not a curved
surface, which makes it easier to mount the light emitting chip
422 on the side wall.
In the meantime, referring to FIG. 3b, a light emitting
15
diode 430 includes substrate 431, light emitting chips 432, lead
terminals (not shown), wires (not shown), a reflective part 435
and a molding part 439.
A base surface 436 of the reflective part 435 may be formed
in a polygon shape which includes curves.
20
As the base surface
436 is formed in a polygon shape which includes curves, a side
wall 437 is also composed of flat and curved side walls, and
the light emitting chips 432 are mounted on the flat side walls.
FIGS.
4a
and
4b
are
a
perspective
view
and
a
cross-sectional view of a light emitting diode according to a
25
conventional art.
FIGS. 5a and 5b are a result diagram of light
11
distribution and a chroma data of the light emitting diode
according to the conventional art and the embodiment of the
present invention.
color
5
mixing
of
FIG. 6 is a table comparing the level of
the
light
emitting
diode
between
the
conventional art and the embodiment of the present invention.
A light emitting diode 40 according to the conventional
art illustrated in FIGS. 4a and 4b includes a substrate 41, a
light emitting chip 42, lead terminals (not shown), wires (not
shown), a reflective part 45 that is formed in a recessed shape
10
and a molding part 419.
The light emitting chips 42 are mounted
on the bottom surface of the reflective part 45.
FIGS. 5a to 6 illustrate simulation results according to
the conventional art and the present invention.
Looking at
specs of the light emitting diodes according to the conventional
15
art and present invention to be simulated, the total size is
3 x 3 x 0.7 mm, the light emitting chip uses an R,G,B light
emitting chip of 350 m x 350 m, the molding part is formed
to have height of 0.3 mm.
Simulations are carried out under
circumstances in which the light emitting diode according to
20
the conventional art has the light emitting chips mounted on
the bottom surface of the reflective part, and the light
emitting diode according to the present invention has the light
emitting chips mounted to be inclined at 135 degrees with
respect to the bottom surface of the reflective part.
25
The location of white points and the level of Δu'v' can
12
be obtained from chroma data.
Here, each of the data indicates
how many points (percentage %) are found below 0.006, in the
value of color difference that is obtained with respect to a
center Pt of a detector or a white Pt (that is, u'v' = 0.198,
5
0.468).
In the conventional art, as for Δu'v' that is the value
of color difference, the number of points below 0.006 is 0.19
out of 100.
The reason why the number is so small is that a
perfect white point value is set as reference and light emitted
10
from one light emitting diode is detected by a detector with
the size of 100 x 100 mm.
If simulation is carried out under
different circumstances, for example, if light emitted from the
light emitting diode is measured by a detector that is located
directly on the light emitting diode, or if the detector is
15
increased in size, the measured value can be large.
As shown in FIG. 6, looking at the case in which the value
of color difference is below 0.006 in respect to the white point,
the white Pt is 0.35 in the present invention (when the first
angle is 135 degrees), which is improved 84% as compared to the
20
conventional art in which the white Pt is 0.19.
Therefore,
color mixing, that is, white color mixing is improved when the
light emitting chip is mounted on the side wall of the reflective
part, as compared to when the light emitting chip is mounted
on the bottom surface of the reflective part.
25
FIGS. 7 and 8 are a perspective view and a cross-sectional
13
view of the light emitting diode according to a second
embodiment of the present invention.
FIG. 9 is a draft
schematically illustrating the light emitting diode shown in
FIG. 7 and FIG. 8.
5
With reference to FIGS. 7 to 9, a light emitting diode 440
according to the second embodiment of the present invention
includes a substrate 441, light emitting chips 442, lead
terminals (not shown), wires (not shown), a reflective part 445,
a protrusion 448 and a molding part 449.
10
The reflective part 445 is formed in a recessed shape on
a first surface of the substrate 441, that is, an upper side
of the substrate.
The reflective part 445 is parallel to the
first surface of the substrate 441, and composed of a base
surface 446 that is formed to have a predetermined recessed
15
depth, and a side wall 447 that is formed to incline at a first
angle θ1 with respect to the base surface 446.
In this case,
the base surface 446 is formed in a circular shape, but as
described above, the base surface may be formed in various
shapes, such as a polygon or a polygon including curves.
20
The light emitting chip 442 is mounted on the side wall
447 of the reflective part 445 so as to be inclined at the first
angle θ1 with respect to the base surface 446.
At this time,
the light emitting chip 442 includes first to fourth light
emitting chips 442a to 442d, the light emitting chips 442a to
25
442d are mounted at predetermined intervals on the side wall.
14
In the present embodiment, the light emitting chips 442a to 442d
are mounted at uniform intervals, but not limited thereto.
The protrusion 448 is formed in the reflective part 445,
the protrusion 448 is formed on the base surface 446 of the
5
reflective part 445, and the protrusion 448 includes a
reflective surface that is inclined at a second angle θ2 with
respect to the base surface 446. The protrusion 448 is formed
in a conical shape as a whole, but can be modified in a different
form, such as polypyramid.
10
In addition, the protrusion 448 is formed to have height
equal to or smaller than the depth of the reflective part 445.
Further, the second angle θ2 formed between the reflective
surface of the protrusion 448 and the base surface 446 can be
changed within the range of 5 to 85 degrees.
15
Likewise, if the
protrusion 448 is formed on the base surface 446 of the
reflective part 445, it is possible to further improve color
mixing effect.
FIG. 9 illustrates an example draft of the light emitting
diode 440.
20
The reflective part 445 of the light emitting diode
440 has depth of 0.3 mm, distance from the center of the base
surface 446 to one end of the side wall 447 is 0.88 mm, and
distance from the center of the base surface 446 to other end
of the side wall 447 is 1.18 mm, and the light emitting chip
442 is mounted on the side wall 447 at a distance of 0.027 mm
25
from the base surface 446.
The light emitting diode 440 shown
15
in FIG. 9 is illustrative not limitative, the type and dimension
of the light emitting diode are not limited thereto.
FIGS. 10a to 10e are modifications of the light emitting
diode shown in FIGS. 7 and 8.
5
FIG. 11 is a table comparing the
level of color mixing of the light emitting diode between the
conventional art and the modifications of FIGS. 10a to 10e.
FIGS. 10a to 10e illustrate schematic cross-sectional
views of the light emitting diode when the second angle θ2, that
is, the angle formed between the reflective surface of the
10
protrusion and the base surface, is modified to 30, 45, 60, 75,
and 85 degrees.
At this time, the protrusion of the light
emitting diode is formed to have height of 0.2 mm, and the
reflective part to have depth of 0.3 mm.
FIG. 11 is a table comparing the level of color mixing of
15
the light emitting diode between the conventional art, the first
embodiment (the light emitting diode without the protrusion
shown in FIG. 1) of the present invention and the modifications
(the light emitting diode shown in FIGS. 10a to 10e) of the
present invention.
20
Looking at the value of color difference below 0.006 in
respect to the white point, the white Pt is 0.19 in the
conventional art, the white Pt is 0.35 in the light emitting
diode shown in FIG. 1, the light emitting diodes according to
FIGS. 10a to 10e have white Pts of 0.46 (θ2 = 30), 0.54 (θ2 =
25
45), 0.27 (θ2 = 60), 0.23 (θ2 = 70) and 0.19 (θ2 = 85),
16
respectively.
On the table, the optimal result is 0.54 obtained when the
second angle θ2 is 45 degrees, which is improved 184% in color
mixing as compared to the conventional art (0.19).
5
FIGS. 12a to 12e are other modifications of the light
emitting diode shown in FIGS. 7 and 8.
FIG. 13 a table comparing
the level of color mixing of the light emitting diode between
the conventional art and the modifications of FIGS. 12a to 12e.
FIGS. 12a to 12e illustrate schematic cross-sectional
10
views of the light emitting diode, when the second angle θ2,
that is, the angle formed between the reflective surface of the
protrusion and the base surface, is modified to 30, 45, 60, 75,
and 85 degrees.
At this time, the protrusion of the light
emitting diode is formed to have height of 0.3 mm, and the
15
reflective part to have depth of 0.3 mm.
FIG. 13 a table comparing the level of color mixing of the
light emitting diode between the conventional art, the first
embodiment (the light emitting diode without the protrusion
shown in FIG. 1) of the present invention and the modifications
20
(the light emitting diodes shown in FIGS. 12a to 12e).
Looking at the value of color difference below 0.006 in
respect to the white point, the white Pt is 0.19 in the
conventional art, the white Pt is 0.35 in the light emitting
diode shown in FIG. 1, and the light emitting diodes according
25
to FIGS. 12a to 12e have white Pts of 0.62 (θ2 = 30), 0.19 (θ2
17
= 45), 0.19 (θ2 = 60), 0.27 (θ2 = 70) and 0.27 (θ2 = 85),
respectively.
On the table, the optimal result is 0.62 obtained when the
second angle θ2 is 30 degrees, which is improved 226% in color
5
mixing as compared to the conventional art (0.19).
FIGS. 14a and 14b are a plan view and a perspective view
of the light emitting diode according to a third embodiment of
the present invention.
With reference to FIGS. 14a and 14b, a light emitting diode
10
unit 450 includes a plurality of light emitting diodes, in the
present embodiment, four light emitting diodes, that is, first
to fourth light emitting diodes (450a to 450d).
Since each
light emitting diode has a uniform constitution, only a first
light emitting diode 450a will be described hereafter.
15
The
first light emitting diode 450a includes a substrate 451a, a
first light emitting chip 452a, lead terminals (not shown),
wires (not shown), a reflective part 455a and a molding part
459.
The reflective part 455a is parallel to the upper side
of the substrate 451a, and composed of a base surface 456a that
20
is formed to have a predetermined recessed depth, and a side
wall 457a that is formed to incline at a predetermined angle
with respect to the base surface 456a.
A single light emitting chip 452a is mounted on the side
wall 457a at a predetermined angle with respect to the base
25
surface 456a.
In the meantime, the first to fourth light
18
emitting chips in the light emitting diode unit 450 can be
disposed at equal intervals.
FIGS. 15 and 16 are an exploded perspective views
illustrating one or other example of a liquid crystal display
5
including a backlight composed of the light emitting diodes
according to the present invention.
With reference to FIGS. 15 and 16, a liquid crystal display
includes an upper accommodation member 300, a liquid crystal
display panel 100, driving circuit parts 220 and 240, a
10
diffusion plate 600, a plurality of optical sheets 700, a light
source unit 400, a mold frame 800 and a lower accommodation
member 900.
A predetermined accommodating space is formed in the mold
frame 800, a backlight unit composed of the diffusion plate 600,
15
the plurality of optical sheets 700 and the light source unit
400 is disposed in the accommodating space of the mold frame.
The liquid crystal display panel 100 that displays image is
disposed at the upper side of the backlight unit.
The driving circuit parts 220 and 240 are connected to the
20
liquid crystal display panel 100, and include a gate side
printed circuit board 224 on which a control IC is mounted and
which applies a predetermined gate signal to a gate line of a
TFT substrate 120, a data side printed circuit board 244 on which
a control IC (integrated circuit) is mounted and which applies
25
a predetermined data signal to a data line of the TFT substrate
19
120, a gate side flexible printed circuit board 222 connecting
the TFT substrate 120 and the gate side printed circuit board
224, and a data side flexible printed circuit board 242
connecting the TFT substrate 120 and the data side printed
5
circuit board 244.
The gate side and data side printed circuit
boards 224 and 244 are connected to the gate side and data side
flexible printed circuit boards 222 and 242 to apply a gate
driving signal and an exterior image signal.
At this time, the
gate side and data side printed circuit boards 224 and 244 can
10
be integrated into one printed circuit board.
In addition, the
flexible printed circuit boards 222 and 242 have a driving IC
(not shown) mounted therein, to transmit RGB (Red, Green, and
Blue) signals generated from the printed circuit boards 224 and
244 to the liquid crystal display panel 100.
15
The light source unit 400 includes the above-described
light emitting diodes 410 to 440 and a printed circuit board
470 having the light emitting diodes 410 to 440 mounted thereon
(refer to FIG. 15).
In the meantime, the light source unit 400 shown in FIG.
20
16 includes the light emitting diode unit 450 shown in FIGS.
14a and 14band the printed circuit board 470 having the light
emitting diode unit 450 mounted thereon.
The diffusion plate 600 and the plurality of optical sheets
700 are disposed at the upper side of the light source unit 400
25
to make uniform luminance distribution of light output from the
20
light source unit 400.
The upper accommodation member 300 is
joined with the mold frame 800 so as to cover edges of the liquid
crystal display panel 100, that is, a non-display region and
a side surface and a bottom surface of the mold frame 800.
5
The
lower accommodation member 900 is disposed at the lower side
of the mold frame 800 to close the accommodating space of the
mold frame.
The above description is about exemplary embodiments of
the light emitting diode according to the present invention,
10
a backlight unit and a liquid crystal display having the same.
The invention is not limited thereto, but is defined by the
appended claims.
Therefore, it should be noted that various
changes and modifications can be made by those skilled in the
art without departing from the technical spirit of the appended
15
claims.
As described above, according to the present invention,
as the light emitting chip is mounted on the side wall of the
reflective part formed on the substrate, it is possible to
improve color mixing of light emitted by the light emitting
20
diode.
21
WHAT IS CLAIMED IS:
1.
A light emitting diode comprising:
a substrate in which a reflective part is formed in a
5
recessed shape; and
at least one light emitting chip that is mounted on the
reflective part of the substrate,
wherein the reflective part is composed of a base surface
and a side wall that is formed to incline at a first angle with
10
respect to the base surface, and the light emitting chip is
mounted on the side wall.
2.
The light emitting diode of claim 1, wherein a
plurality of the light emitting chips are mounted on the side
15
wall at predetermined intervals.
3.
The light emitting diode of claim 2, wherein the
plurality of light emitting chips are mounted on the side wall
at equal intervals.
20
4.
The light emitting diode of claim 1, wherein the
first angle is in the range of 120 to 150 degrees.
5.
25
The light emitting diode of claim 1, further
comprising:
22
a protrusion formed on the base surface.
6.
The light emitting diode of claim 5, wherein the
protrusion is formed to have height equal to or smaller than
5
depth of the reflective part.
7.
The light emitting diode of claim 5, wherein the
protrusion includes a reflective surface that is formed to
incline at a second angle with respect to the base surface.
10
8.
The light emitting diode of claim 7, wherein the
second angle is in the range of 5 to 85 degrees.
9.
15
The light emitting diode of claim 7, wherein the
protrusion is formed in a conical shape or a polypyramid shape.
10.
The light emitting diode of claim 1, wherein the
light emitting chip includes at least one of a red light emitting
chip, a green light emitting chip and a blue light emitting chip.
20
11.
The light emitting diode of claim 1, wherein the
light emitting chip includes a white light emitting chip.
12.
25
The light emitting diode of claim 1, further
comprising:
23
a lead terminal and a wire to apply power to the light
emitting chip.
13.
5
The light emitting diode of claim 1, further
comprising:
a molding part to cap the light emitting chip.
14.
The light emitting diode of claim 1, wherein the
base surface is formed in a circular shape, a polygon shape,
10
and a polygon shape including curves.
15.
A backlight unit comprising:
a light emitting diode including a substrate in which a
reflective part is formed in a recessed shape and a plurality
15
of light emitting chips mounted on the reflective part of the
substrate, in which the reflective part is composed of a base
surface and a side wall that is formed to incline at a first
angle with respect to the base surface, and the plurality of
light emitting chips are mounted on the side wall; and
20
a light source unit including a printed circuit board on
which the light emitting diode is mounted.
16.
The backlight unit of claim 15, further comprising:
a protrusion that is formed to incline at a second angle
25
with respect to the base surface.
24
17.
A backlight unit comprising:
a light emitting diode including a substrate in which a
reflective part is formed in a recessed shape and a single light
5
emitting chip mounted on the reflective part of the substrate,
in which the reflective part is composed of a base surface and
a side wall that is formed to incline at a first angle with
respect to the base surface, and the single light emitting chip
is mounted on the side wall; and
10
a light source unit including a printed circuit board on
which a plurality of the light emitting diodes are mounted, in
which the plurality of light emitting diodes are divided into
light emitting diode units each composed of two or more light
emitting diodes so as to be mounted on the printed circuit board.
15
18.
The backlight unit of claim 17, further comprising:
a protrusion having a reflective surface that is formed
to incline at a second angle with respect to the base surface.
20
19.
A liquid crystal display comprising:
a backlight unit which has a light emitting diode including
a substrate in which a reflective part is formed in a recessed
shape and a plurality of light emitting chips mounted on the
reflective part of the substrate, in which the reflective part
25
is composed of a base surface and a side wall that is formed
25
to incline at a first angle with respect to the base surface,
and the plurality of light emitting chips are mounted on the
side wall, and a light source unit including a printed circuit
board on which the plurality of light emitting diodes are
5
mounted; and
a liquid crystal display panel disposed on the backlight
unit to display image.
20.
10
The liquid crystal display of claim 19, further
comprising:
a protrusion including a reflective surface that is formed
to incline at a second angle with respect to the base surface.
21.
15
A liquid crystal display comprising:
a backlight unit which has a light emitting diode including
a substrate in which a reflective part is formed in a recessed
shape and a single light emitting chip mounted on the reflective
part of the substrate, in which the reflective part is composed
of a base surface and a side wall that is formed to incline at
20
a first angle with respect to the base surface, and the single
light emitting chip is mounted on the side wall, and a light
source unit including a printed circuit board on which the
plurality of light emitting diodes are mounted, in which the
plurality of light emitting diodes are divided into light
25
emitting diode units each composed of two or more light emitting
26
diodes so as to be mounted on the printed circuit board; and
a liquid crystal display panel disposed on the backlight
unit to display image.
5
22.
The liquid crystal display of claim 21, further
comprising:
a protrusion including a reflective surface that is formed
to incline at a second angle with respect to the base surface.
27
ABSTRACT OF THE DISCLOSURE
The present invention relates to a light emitting diode
with improved coloring mixing, and a backlight unit and a liquid
5
crystal displaying unit having the same.
The present invention
provides: a light emitting diode including a substrate in which
a reflective part is formed in a recessed shape, and at least
one light emitting chip that is mounted on the reflective part
of the substrate, in which the reflective part is composed of
10
a base surface and a side wall that is formed to incline at a
first angle with respect to the base surface, and the light
emitting chip is mounted on the side wall; a backlight unit;
and a liquid crystal display having the light emitting diode.
28
[FIG. 6]
CONVENTIONAL ART
45 DEGREES
5
[FIG. 11]
CONVENTIONAL ART
45 DEGREES
(FLAT REFLECTIVE PLATE)
10
[FIG. 13]
CONVENTIONAL ART
45 DEGREES
(FLAT FREFLECTIVE PLATE)
29