U.S. patent number RE45,805 [Application Number 14/308,793] was granted by the patent office on 2015-11-17 for display device.
This patent grant is currently assigned to LG ELECTRONICS INC.. The grantee listed for this patent is LG ELECTRONICS INC.. Invention is credited to Deoksoo Kim, Sanghoon Kim, Sungwoo Kim, Youngmin Kim, Hoyoung Seo.
United States Patent |
RE45,805 |
Kim , et al. |
November 17, 2015 |
**Please see images for:
( Certificate of Correction ) ** |
Display device
Abstract
A display device is disclosed. The display device includes a
display panel, a frame disposed in the rear of the display panel, a
backlight unit disposed between the display panel and the frame, a
driver attached to a back surface of the frame, and a back cover
that is disposed in the rear of the driver and is connected to the
back surface of the frame. At least one of the frame and the back
cover includes a heat dissipation member.
Inventors: |
Kim; Youngmin (Seoul,
KR), Kim; Sanghoon (Seoul, KR), Seo;
Hoyoung (Seoul, KR), Kim; Deoksoo (Seoul,
KR), Kim; Sungwoo (Seoul, KR) |
Applicant: |
Name |
City |
State |
Country |
Type |
LG ELECTRONICS INC. |
Seoul |
N/A |
KR |
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Assignee: |
LG ELECTRONICS INC. (Seoul,
KR)
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Family
ID: |
43770426 |
Appl.
No.: |
14/308,793 |
Filed: |
June 19, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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Reissue of: |
12977774 |
Dec 23, 2010 |
8564731 |
Oct 22, 2013 |
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Foreign Application Priority Data
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Dec 23, 2009 [KR] |
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10-2009-0129695 |
Mar 17, 2010 [KR] |
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10-2010-0023955 |
Mar 30, 2010 [KR] |
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10-2010-0028685 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G02F
1/133308 (20130101); G02F 1/133603 (20130101); G02F
1/133611 (20130101); G02F 1/1362 (20130101); G02F
1/133607 (20210101) |
Current International
Class: |
G02F
1/1333 (20060101); G02F 1/1335 (20060101) |
Field of
Search: |
;349/58,61,64,69 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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WO 2008/029540 |
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Mar 2008 |
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WO |
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Other References
European Office Action dated Aug. 16, 2013 issued in Application
No. 10 01 6057. cited by applicant .
United States Notice of Allowance dated Jun. 10, 2013 issued in
U.S. Appl. No. 12/977,774. cited by applicant .
European Search Report dated Dec. 21, 2011 issued in Application
No. 10 01 6057. cited by applicant .
European Office Action dated Aug. 16, 2013 issued in Application
No. 10 016 057.1. cited by applicant.
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Primary Examiner: Whittington; Kenneth J
Attorney, Agent or Firm: Ked & Associates, LLP
Claims
What is claimed is:
1. A display device comprising: a display panel; a frame disposed
in the rear of the display panel; a backlight unit disposed between
the display panel and the frame; at least one .[.adhesive.].
.Iadd.optical .Iaddend.layer disposed between .Iadd.the display
panel and .Iaddend.the backlight unit .[.and the frame.].; a driver
in the rear of the frame; and a back cover that is disposed in the
rear of the driver.Iadd.,.Iaddend. wherein the .Iadd.backlight unit
includes a substrate including a plurality of subsidiary
substrates, a plurality of light sources disposed on the plurality
of subsidiary substrates and configured to emit light, and an
.Iaddend.adhesive layer includes a plurality of subsidiary adhesive
layers .[.that are positioned parallel to one another to be.].
spaced apart from one another, .Iadd.positioned between the frame
and the substrate, and attached to the frame and the
substrate,.Iaddend. .[.wherein the substrate includes a plurality
of subsidiary substrates each including the plurality of light
sources, wherein the adhesive layer is positioned between the two
adjacent subsidiary substrates,.]. wherein the .[.substrate.].
.Iadd.the plurality of subsidiary substrates .Iaddend.includes
first, second, and third subsidiary substrates that are
.[.positioned parallel.]. .Iadd.adjacent .Iaddend.to one another,
.Iadd.and .Iaddend. wherein the adhesive layer includes a first
subsidiary adhesive layer .[.commonly overlapping.]. .Iadd.attached
to .Iaddend.the first and second subsidiary substrates and a second
subsidiary adhesive layer .[.commonly overlapping.]. .Iadd.attached
to .Iaddend.the second and third subsidiary substrates.
2. The display device of claim 1, wherein a portion of the back
surface of the frame is exposed.
3. The display device of claim 1, wherein a distance between a
first region of the frame and the driver is different from a
distance between a second region of the frame opposite the first
region and the driver, wherein a distance between the first region
and the back cover is different from a distance between the second
region and the back cover.
4. The display device of claim 3, wherein the distance between the
first region of the frame and the driver is greater than the
distance between the second region of the frame and the driver,
wherein the distance between the first region and the back cover is
greater than the distance between the second region and the back
cover.
5. The display device of claim 1, wherein a hole is formed in the
frame, wherein a wire passes through the hole and connects the
display panel to the driver.
6. The display device of claim 1, wherein the backlight unit
.Iadd.further .Iaddend.includes.[.: a substrate; a light source
disposed on the substrate; and.]. a resin layer disposed on the
substrate to cover the light source.
.Iadd.7. The display device of claim 1, wherein the adhesive layer
is formed to transfer heat..Iaddend.
.Iadd.8. The display device of claim 1, wherein the plurality of
subsidiary adhesive layers are positioned parallel to one
another..Iaddend.
.Iadd.9. The display device of claim 1, wherein at least one of the
plurality of light sources includes: a molded body having a cavity,
a light emitting element mounted in the cavity, and an
encapsulation material filling the cavity..Iaddend.
.Iadd.10. The display device of claim 9, wherein the encapsulation
material includes a phosphor to change a color of light emitted
from the light emitting element..Iaddend.
.Iadd.11. The display device of claim 1, the backlight unit further
including a reflection layer disposed on the substrate, and
configured to reflect the light emitted from the plurality of light
sources..Iaddend.
.Iadd.12. The display device of claim 11, wherein the reflection
layer is a single sheet..Iaddend.
.Iadd.13. The display device of claim 1, wherein a size of the
first subsidiary adhesive layer is different from a size of the
second subsidiary adhesive layer..Iaddend.
.Iadd.14. The display device of claim 13, wherein the size
comprises at least one of a width and a length of the first and
second subsidiary adhesive layer..Iaddend.
.Iadd.15. The display device of claim 1, wherein the adhesive layer
further comprises a third subsidiary adhesive layer spaced apart
from the second subsidiary adhesive layer, wherein a distance
between the first and second subsidiary adhesive layers is
substantially the same as a distance between second and third
subsidiary adhesive layers..Iaddend.
.Iadd.16. The display device of claim 1, further comprising at
least one connector disposed in the rear of the at least one of the
plurality of subsidiary substrates..Iaddend.
.Iadd.17. The display device of claim 16, wherein each of the
connectors is disposed in the rear of each of the subsidiary
substrates..Iaddend.
.Iadd.18. The display device of claim 16, wherein each of the
connectors is connected to a cable, the cable connected to a power
supply unit through a hole formed in the frame..Iaddend.
.Iadd.19. The display device of claim 1, wherein at least two of
the plurality of subsidiary adhesive layers are disposed on one of
the plurality of subsidiary substrates..Iaddend.
.Iadd.20. The display device of claim 1, wherein the plurality of
light sources on the at least one of the plurality of subsidiary
substrates are arranged in parallel rows, the parallel rows
including at least two rows, wherein a number of the plurality of
light sources on one row of the at least two rows is same to a
number of the plurality of light source on another row of the at
least two rows..Iaddend.
.Iadd.21. The display device of claim 1, wherein the plurality of
light sources on the at least one of the plurality of subsidiary
substrates are arranged in parallel rows including a first row, a
second row, and a third row disposed in sequential, light sources
of the first row arranged asymmetrical with light sources of the
second row, and light sources of the first row arranged symmetrical
with light sources of the third row..Iaddend.
.Iadd.22. The display device of claim 1, wherein the plurality of
light sources on the at least one of the plurality of subsidiary
substrates are arranged in parallel rows including a first row and
a second row disposed sequentially, and light sources of the first
row among the plurality of light sources and light sources of the
second row among the plurality of light sources arranged in zigzag
manner..Iaddend.
.Iadd.23. The display device of claim 1, wherein the plurality of
light sources comprise a first row on the first subsidiary
substrate and a second row on the second subsidiary substrate, the
first and second subsidiary substrates being adjacent to each
other, and the first row and the second row being provided on
corresponding edge areas of the first and second subsidiary
substrate, wherein light sources of the first row are arranged
asymmetrical with light sources of the second row..Iaddend.
Description
.Iadd.CROSS-REFERENCE TO RELATED APPLICATIONS.Iaddend.
This application .Iadd.is a Reissue Application of U.S. Pat. No.
8,564,731, which .Iaddend.claims .[.the benefit of.].
.Iadd.priority under 35 U.S.C. .sctn.119 to .Iaddend.Korean Patent
Application Nos. 10-2009-0129695 filed on Dec. 23, 2009,
10-2010-0023955 filed on Mar. 17, 2010, and 10-2010-0028685 filed
on Mar. 30, 2010, .[.which are.]. .Iadd.whose entire disclosures
.Iaddend.are incorporated herein by reference for all purposes as
if fully set forth herein. .Iadd.More than one reissue application
has been filed for the reissue of U.S. Pat. No. 8,564,731. The
Reissue Application numbers are 14/308,793 and 14/825,024.
.Iaddend.
BACKGROUND OF THE INVENTION
1. Field of the Invention
Embodiments of the invention relate to a display device.
2. Description of the Related Art
With the development of the information society, various demands
for display devices have been increasing. Various display devices,
such as a liquid crystal display (LCD), a plasma display panel
(PDP), an electroluminescent display (ELD), and a vacuum
fluorescent display (VFD), have been recently studied and used, so
as to meet the various demands for the display devices.
Out of the display devices, a liquid crystal display panel of the
liquid crystal display includes a liquid crystal layer, and a thin
film transistor (TFT) substrate and a color filter substrate that
are positioned opposite each other with the liquid crystal layer
interposed therebetween. The liquid crystal display panel displays
an image using light provided by a backlight unit of the liquid
crystal display.
SUMMARY OF THE INVENTION
In one aspect, there is a display device comprising a display
panel, a frame disposed in the rear of the display panel, a driver
attached to a back surface of the frame, and a back cover that is
disposed in the rear of the driver and is connected to the back
surface of the frame.
In another aspect, there is a display device comprising a display
panel, a frame disposed in the rear of the display panel, a
backlight unit disposed between the display panel and the frame, a
driver attached to a back surface of the frame, and a back cover
that is disposed in the rear of the driver and is connected to the
back surface of the frame, wherein at least one of the frame and
the back cover includes a heat dissipation member.
In yet another aspect, there is a display device comprising a
display panel, a frame disposed in the rear of the display panel, a
backlight unit disposed between the display panel and the frame, an
adhesive layer disposed between the backlight unit and the frame, a
driver attached to a back surface of the frame, and a back cover
that is disposed in the rear of the driver and is connected to the
back surface of the frame, wherein the backlight unit includes a
substrate, a light source disposed on the substrate, and a resin
layer disposed on the substrate to cover the light source.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further
understanding of the invention and are incorporated in and
constitute a part of this specification, illustrate embodiments of
the invention and together with the description serve to explain
the principles of the invention. In the drawings:
FIGS. 1 to 41 illustrate a configuration of a display device
according to an exemplary embodiment of the invention;
FIGS. 42 to 46 illustrate a disposition relationship between a
frame, a driver, and a back cover;
FIGS. 47 to 54 illustrate a display device including a heat
dissipation member; and
FIGS. 55 to 68 illustrate a substrate including a plurality of
subsidiary substrates.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Reference will now be made in detail embodiments of the invention
examples of which are illustrated in the accompanying drawings. In
this regard, each of all display devices, backlight units, light
source devices, and any device that includes such backlight unit or
light source device discussed below is operatively coupled and
configured. Further, a backlight unit according to embodiments of
the invention preferably is fixed to a back of a display panel and
has a same or similar size as the display panel to correspond to
the entire display region of the display panel. Furthermore, such a
backlight unit preferably includes a plurality of light sources
which are disposed in arrays, lines, patterns, etc. throughout the
entire area of the backlight unit that corresponds to the entire
display region of the display panel. As such, the light sources are
not just located at one side of the display panel, but are
preferably dispersed below throughout the entire display region of
the display panel. In these figures, arrows indicate a general
light emitting direction of the light source, e.g., a general
direction in which the light from a light emitting surface of the
light source is emitted, but the light from the light source may
emit not necessarily in a single line but through an area in the
indicated direction.
According to various embodiments of the invention, any one or more
features from one embodiment/example/variation of the invention can
be applied to (e.g., added, substituted, modified, etc.) any one or
more other embodiments/examples/variations discussed below
according to the invention. Further any operations/methods
discussed below can be implemented in any of these devices/units or
other suitable devices/units.
FIGS. 1 to 41 illustrate a configuration of a display device
according to an exemplary embodiment of the invention. As shown in
FIG. 1, a display device 100 according to an exemplary embodiment
of the invention may include a display panel 110, an optical layer
250, a backlight unit 200, a front cover 130, a frame 135, a driver
140, and a back cover 150.
The display panel 110 is an image displaying element. The display
panel 110 may include a first substrate (not shown) and a second
substrate (not shown) that are positioned opposite each other with
a liquid crystal layer interposed therebetween and are attached to
each other. Although it is not shown, a plurality of scan lines and
a plurality of data lines may cross each other in a matrix form on
the first substrate also referred to as a thin film transistor
(TFT) array substrate, thereby defining a plurality of pixels. Each
pixel may include a thin film transistor capable of switching on
and off a signal and a pixel electrode connected to the thin film
transistor.
Red (R), green (G), and blue (B) color filters corresponding to
each pixel and black matrixes may be positioned on the second
substrate also referred to as a color filter substrate. The black
matrixes may surround the R, G, and B color filters and may cover a
non-display element such as the scan lines, the data line, and the
thin film transistors. A transparent common electrode covering the
R, G, and B color filters and the black matrixes may be positioned
on the second substrate.
A printed circuit board (PCB) may be connected to at least one side
of the display panel 110 through a connection member such as a
flexible circuit board and a tape carrier package (TCP), and the
display panel 110 may be closely attached to a back surface of the
frame 135 in a module process.
When the thin film transistors selected by each scan line are
switched on in response to an on/off signal that is transferred
from a gate driving circuit 113 through the scan lines, a data
voltage of a data driving circuit 114 is transferred to the
corresponding pixel electrode through the data lines and an
arrangement direction of liquid crustal molecules changes by an
electric field between the pixel electrode and the common
electrode. Hence, the display panel 110 having the above-described
structure displays an image by adjusting a transmittance difference
resulting from changes in the arrangement direction of the liquid
crustal molecules.
The backlight unit 200 may be positioned at a back surface of the
display panel 110.
The optical layer 250 may be positioned between the backlight unit
200 and the display panel 110.
The display panel 110 and the backlight unit 200 may form a module
using the front cover 130 and the frame 135. The front cover 130
positioned on a front surface of the display panel 110 may be a top
cover and may have a rectangular frame shape covering an upper
surface and a side surface of the display panel 110. An image
achieved by the display panel 110 may be displayed by opening a
front surface of the front cover 130.
The frame 135 positioned on a back surface of the backlight unit
200 may have a rectangular plate shape. The frame 135 may serve as
a base element of the display device 100 when the display panel 110
and the backlight unit 200 form the module.
The driver 140 may be positioned on one surface of the frame 135 by
a driver chassis 145. The driver 140 may includes a driving
controller 141, a main board 142, and a power supply unit 143. The
driving controller 141 may be a timing controller and controls
operation timing of each of driving circuits of the display panel
110. The main board 142 transfers a vertical synchronous signal, a
horizontal synchronous signal, and a RGB resolution signal to the
driving controller 141. The power supply unit 143 applies a power
to the display panel 110 and the backlight unit 200. The driver 140
may be covered by the back case 150.
Hereinafter, the backlight unit 200 having various configurations
is described in detail.
As shown in FIGS. 2 and 3, the backlight unit 200 may include a
substrate 210, a plurality of light sources 220, a resin layer 230,
and a reflection layer 240.
The plurality of light sources 220 may be formed on the substrate
210, and the resin layer 230 may be formed on the substrate 210 so
as to cover the light sources 220.
The substrate 210 may be a substrate on which the plurality of
light sources 220 are mounted. An electrode pattern (not shown) for
connecting the light sources 220 to an adapter (not shown) for a
power supply may be formed on the substrate 210. For example, a
carbon nanotube electrode pattern for connecting the light sources
220 to the adapter may be formed on the substrate 210.
The substrate 210 may be formed of polyethylene terephthalate
(PET), glass, polycarbonate (PC), or silicon. The substrate 210 may
be a printed circuit board (PCB) substrate, on which the plurality
of light sources 220 are mounted, and may be formed in a film
form.
The light source 220 may be one of a light emitting diode (LED)
chip and a light emitting diode package having at least one light
emitting diode chip, but can be other type. In the embodiment of
the invention, the light emitting diode package is described as an
example of the light source 220.
The LED package constituting the light source 220 may be classified
into a top view type LED package and a side view type LED package
based on a facing direction of a light emitting surface of the LED
package. In the embodiment of the invention, the light source 220
may be configured using at least one of the top view type LED
package, in which the light emitting surface is upward formed, and
the side view type LED package in which the light emitting surface
is formed toward the side.
If the side view type LED package is used as the light source 220
in the embodiment of the invention, each of the light sources 220
may have a light emitting surface at a side thereof and may emit
light in a lateral direction, i.e., in an extension direction of
the substrate 210 or the reflection layer 240. Thus, a thin profile
of the backlight unit 200 may be achieved by reducing a thickness
"e" of the resin layer 230 formed on the light sources 220. As a
result, a thin profile of the display device 100 may be
achieved.
The light source 220 may be configured by a colored LED emitting at
least one of red light, green light, blue light, etc. or a white
LED emitting white light. In addition, the colored LED may include
at least one of a red LED, a blue LED, and a green LED. The
disposition and emitting light of the light emitting diode can be
variously changed within a technical scope of the embodiment.
The resin layer 230 transmits light emitted by the light sources
220, and at the same time diffuses the light emitted by the light
sources 220, thereby allowing the light sources 220 to uniformly
provide the light to the display panel 110. The resin layer 230
encapsulates (entirely covers) the light sources 220 on the
substrate 210.
The reflection layer 240 is positioned on the substrate 210 and
reflects light emitted by the light sources 220. The reflection
layer 240 may be formed in an area excluding a formation area of
the light sources 220 from the substrate 210. The reflection layer
240 reflects light emitted from the light sources 220 and again
reflects light totally reflected from a boundary of the resin layer
230, thereby more widely diffusing light. The reflection layer 240
is a layer capable of reflecting the impinging light or a part
thereof.
The reflection layer 240 may contain at least one of metal and
metal oxide that are a reflection material. For example, the
reflection layer 240 may contain metal or metal oxide having a high
reflectance, such as aluminum (Al), silver (Ag), gold (Au), and
titanium dioxide (TiO.sub.2). In this case, the reflection layer
240 may be formed by depositing or coating the metal or the metal
oxide on the substrate 210 or by printing a metal ink on the
substrate 210. The deposition method may use a heat deposition
method, an evaporation method, or a vacuum deposition method such
as a sputtering method. The coating method or the printing method
may use a gravure coating method or a silk screen method.
The resin layer 230 on the substrate 210 may be formed of a
material capable of transmitting light, for example, silicon or
acrylic resin. Other materials may be used for the resin layer 230.
For example, various types of resin may be used. Further, the resin
layer 230 may be formed of a resin having a refractive index of
approximately 1.4 to 1.6, so that the backlight unit 200 has a
uniform luminance by diffusing light emitted from the light sources
220. For example, the resin layer 230 may be formed of any one
material selected from the group consisting of polyethylene
terephthalate (PET), polycarbonate (PC), polypropylene,
polyethylene, polystyrene, polyepoxy, silicon, acryl, etc.
The resin layer 230 may contain a polymer resin having an adhesion
so as to tightly and closely adhere to the light sources 220 and
the reflection layer 240. For example, the resin layer 230 may
contain an acrylic resin such as unsaturated polyester,
methylmethacrylate, ethylmethacrylate, isobutylmethacrylate, normal
butylmethacrylate, normal butylmethylmethacrylate, acrylic acid,
methacrylic acid, hydroxy ethylmethacrylate, hydroxy
propylmethacrylate, hydroxy ethylacrylate, acrylamide, methylol
acrylamide, glycidyl methacrylate, ethylacrylate, isobutylacrlate,
normal butylacrylate, 2-ethylhexyl acrylate polymer, copolymer, or
terpolymer, etc., an urethane resin, an epoxy resin, a melamine
resin, etc.
The resin layer 230 may be formed by applying and curing a liquid
or gel-type resin on the substrate 210 on which the light sources
220 and the reflection layer 240 are formed. Alternatively, the
resin layer 230 may be formed by applying and partially curing a
resin on a support sheet and then attaching the resin to the
substrate 210.
A diffusion plate 245 may be formed on the resin layer 230 to
upward diffuse light emitted from the light sources 220. The
diffusion plate 24 may be directly attached to the resin layer 230
or may be attached to the resin layer 230 using a separate adhesive
member.
A thickness of the backlight unit 200 having the above-described
structure and a thickness of each of components constituting the
backlight unit 200 may be adjusted so as to efficiently use light
provided to the display panel 110.
More specifically, a total thickness "a" of the backlight unit 200
may be approximately 1.7 mm to 3.5 mm, for example, approximately
2.8 mm. A thickness "b" of the substrate 210 constituting the
backlight unit 200 may be approximately 0.2 mm to 0.8 mm, for
example, approximately 0.5 mm. A thickness "c" of the reflection
layer 240 on the substrate 210 may be approximately 0.02 mm to 0.08
mm, for example, approximately 0.05 mm. Further, a thickness "d" of
the light source 220 arranged on the substrate 210 may be
approximately 0.8 mm to 1.6 mm, for example, approximately 1.2 mm.
The thickness "e" of the resin layer 230 covering the light source
220 may be approximately 0.8 mm to 2.4 mm, for example,
approximately 1.3 mm. A thickness "f" of the diffusion plate 245 on
the resin layer 230 may be approximately 0.7 mm to 1.3 mm, for
example, approximately 1.0 mm.
As the thickness "e" of the resin layer 230 increases, light
emitted from the light sources 220 may be more widely diffused.
Hence, the backlight unit 200 may provide light having the uniform
luminance to the display panel 110. On the other hand, as the
thickness "e" of the resin layer 230 increases, an amount of light
absorbed in the resin layer 230 may increase. Hence, the luminance
of light which the backlight unit 200 provides to the display panel
110 may entirely decrease.
Accordingly, the thickness "e" of the resin layer 230 may be equal
to the thickness "d" of the light source 220 or may be equal to or
less than 1.5 times the thickness "d" of the light source 220, so
that the backlight unit 200 can provide light having the uniform
luminance to the display panel 110 without an excessive reduction
in the luminance.
Alternatively, as shown in FIG. 4, the backlight unit 200 may have
the structure in which the reflection layer 240 covers an upper
surface of the substrate 210 in the non-formation area of the light
sources 220. For example, the reflection layer 240 may be formed on
the substrate 210 and may have a plurality of holes, into which the
light sources 220 may be inserted, at a location corresponding to a
formation location of the light sources 220. The light sources 220
may upwardly protrude from the holes of the reflection layer 240
and may be covered by the resin layer 230.
Alternatively, as shown in FIG. 5, the plurality of light sources
220 may be mounted on the substrate 210, and the resin layer 230
may be disposed on the substrate 210. The reflection layer 240 may
be formed between the substrate 210 and the resin layer 230, more
particularly, on an upper surface of the substrate 210.
The resin layer 230 may include a plurality of scattering particles
231. The scattering particles 231 may scatter or refract incident
light, thereby more widely diffusing light emitted from the light
sources 220.
The scattering particles 231 may be formed of a material having a
refractive index different from a formation material of the resin
layer 230 so as to scatter or refract the light emitted from the
light source 220. More particularly, the scattering particles 231
may be formed of a material having a refractive index greater than
silicon-based resin or acrylic resin forming the resin layer 230.
For example, the scattering particles 231 may be formed of
polymethylmethacrylate (PMMA)/styrene copolymer (MS),
polymethylmethacrylate (PMMA), polystyrene (PS), silicon, titanium
dioxide (TiO.sub.2), and silicon dioxide (SiO.sub.2), or a
combination thereof. Further, the scattering particles 231 may be
formed of a material having a refractive index less than the
formation material of the resin layer 230. For example, the
scattering particles 231 may be formed by generating bubbles in the
resin layer 230. Other materials may be used for the resin layer
230. For example, the scattering particle 231 may be formed using
various polymer materials or inorganic particles.
The optical layer 250 may be disposed on the top of the resin layer
230. The optical layer 250 may include at least one prism sheet 251
and/or at least one diffusion sheet 252. In this case, a plurality
of sheets constituting the optical layer 250 are not separated from
one another and are attached to one another. Thus, the thickness of
the optical layer 250 or the thickness of the backlight unit 200
may be reduced because of the above structure of the optical layer
250.
A lower surface of the optical layer 250 may closely adhere to the
resin layer 230, and an upper surface of the optical layer 250 may
closely adhere to the lower surface of the display panel 110, i.e.,
the lower polarizing plate 140.
The diffusion sheet 252 may diffuse incident light to thereby
prevent light coming from the resin layer 230 from being partially
concentrated. Hence, the diffusion sheet 252 may further uniformize
the luminance of light. Further, the prism sheet 251 may focus
light coming from the diffusion sheet 252, thereby allowing the
light to be vertically incident on the display panel 110.
In the embodiment of the invention, at least one of the prism sheet
251 and the diffusion sheet 252 constituting the optical layer 250
may be removed. The optical layer 250 may further include other
functional layers in addition to the prism sheet 251 and/or the
diffusion sheet 252.
The reflection layer 240 may include a plurality of holes (not
shown) at locations corresponding to formation locations of the
light sources 220, and the light sources 220 on the substrate 210
underlying the reflection layer 240 may be inserted into the
holes.
In this case, the light sources 220 are downwardly inserted into
the holes of the reflection layer 240, and at least a portion of
each of the light sources 220 may protrude from the upper surface
of the reflection layer 240. Because the backlight unit 200 is
configured using the structure in which the light sources 220 are
respectively inserted into the holes of the reflection layer 240, a
fixation strength between the substrate 210 and the reflection
layer 240 can be further improved.
Alternatively, as shown in FIG. 6, each of the plurality of light
sources 220 of the backlight unit 200 has the light emitting
surface on the side thereof and can emit light in a lateral
direction, e.g., a direction in which the substrate 210 or the
reflection layer 240 extends.
For example, the plurality of light sources 220 may be configured
using the side view type LED package. As a result, it is possible
to address a problem that the light sources 220 are observed as a
hot spot on the screen and to slim the backlight unit 200.
Furthermore, the thin profile of the display device 100 can be
achieved because of a reduction of the thickness "e" of the resin
layer 230.
In this case, the light sources 220 may emit light having a
predetermined orientation angle of .alpha. being, for example,
90.degree. to 150.degree. about a first direction x (indicated by
an arrow). Hereinafter, a direction of light emitted from the light
sources 220 is indicated as the first direction x.
In the embodiment of the invention, light is emitted and diffused
upward from the light sources 220 by forming a pattern on the resin
layer 230, and thus the backlight unit 200 can emit light having a
uniform luminance.
Alternatively, the light sources 220 illustrated in FIGS. 7 to 13
may emit light from the side of the light sources 220 in a lateral
direction in the same manner as FIG. 6. Other manners may be used.
For example, the light sources 220 may emit light from the top of
the light sources 220.
As shown in FIG. 7, a pattern layer including a plurality of first
patterns 232 may be formed on the top of the resin layer 230 of the
backlight unit 200 including the light sources 220. More
specifically, the plurality of first patterns 232 of the pattern
layer may be formed on the resin layer 230 at locations
corresponding to the formation locations of the light sources 220
(i.e., where the light sources 220 are located).
For example, the first patterns 232 formed on the top of the resin
layer 230 may be a pattern capable of reflecting at least a portion
of light emitted from the light sources 220.
The first patterns 232 on the resin layer 230 may prevent an
increase in a luminance of light in an area adjacent to the light
sources 220, and thus the backlight unit 200 may provide light
having the uniform luminance.
In other words, the first patterns 232 are formed on the resin
layer 230 at the locations corresponding to the formation locations
of the light sources 220 and selectively reflect light emitted
upward from the light sources 220, thereby reducing the luminance
of light in the area adjacent to the light sources 220. The light
reflected by the first patterns 232 may be diffused in a lateral
direction.
More specifically, the light emitted upward from the light sources
220 is diffused in the lateral direction by the first patterns 232,
and at the same time is reflected downward. The light reflected by
the first patterns 232 is again diffused in the lateral direction
by the reflection layer 240, and at the same time is reflected
upward. In other words, the first patterns 232 may reflect 100% of
incident light. Alternatively, the first patterns 232 may reflect a
portion of the incident light and may transmit a portion of the
incident light. As above, the first patterns 232 may control the
transfer of light passing through the resin layer 230 and the first
patterns 232. As a result, the light emitted from the light sources
220 may be widely diffused in the lateral direction and other
directions as well as the upward direction, and thus the backlight
unit 200 may emit the light having the uniform luminance.
The first patterns 232 may include a reflection material such as
metal. For example, the first patterns 232 may include metal having
a reflectance of 90% or more such as aluminum, silver, and gold.
For example, the first patterns 232 may be formed of a material
capable of transmitting 10% or less of incident light and
reflecting 90% or more of the incident light.
In this case, the first patterns 232 may be formed by depositing or
coating the above-described metal. As another method, the first
patterns 232 may be formed through a printing process using a
reflection ink including a metal, for example, a silver ink in
accordance with a previously determined pattern.
Further, the first patterns 232 may have a color having a high
brightness, for example, a color close to white so as to improve a
reflection effect of the first patterns 232. More specifically, the
first pattern 232 may have a color having the brightness greater
than the resin layer 230.
The first patterns 232 may contain metal oxide. For example, the
first patterns 232 may include titanium dioxide (TiO.sub.2). More
specifically, the first patterns 232 may be formed by printing a
reflection ink containing titanium dioxide (TiO.sub.2) in
accordance with a previously determined pattern.
As shown in FIGS. 7 to 10, the formation of the first patterns 232
at the locations corresponding to the locations of the light
sources 220 may include a case where a middle portion of the first
pattern 232 coincides with a middle portion of the light source 220
corresponding to the first pattern 23 as shown in FIG. 7, and cases
where the middle portion of the first pattern 232 does not
necessarily coincide with the middle portion of the corresponding
light source 220 by a predetermined distance as shown in FIGS.
8-10.
As shown in FIG. 8, the middle portion of the first pattern 232 may
not coincide with the middle portion of the light source 220
corresponding to the first pattern 232.
For example, when the light emitting surface of the light source
220 faces not the upward direction but the lateral direction and
therefore light is emitted from the light source 220 in the lateral
direction, a luminance of light emitted from the side of the light
source 220 may decrease while the light emitted from the side of
the light source 220 travels through the resin layer 230 in a
direction indicated by an arrow of FIG. 8. Hence, light in a first
area directly adjacent to the light emitting surface of the light
source 220 may have a luminance greater than light in an area
around the light emitting surface of the light source 220. Light in
a second area adjacent to an opposite direction of the light
emitting surface may have a luminance less than the light in the
first area. Thus, the first pattern 232 may be formed by moving in
an emission direction of light from the light source 220. In other
words, the middle portion of the first pattern 232 may be formed at
a location (slightly) deviated from the middle portion of the
corresponding light source 220 toward the light emitting
direction.
As shown in FIG. 9, the first pattern 232 may be formed at a
location deviated further than the first pattern 232 illustrated in
FIG. 8 toward the light emitting direction. In other words, a
distance between the middle portion of the first pattern 232 and
the middle portion of the corresponding light source 220 in FIG. 9
may be longer than a distance between the middle portion of the
first pattern 232 and the middle portion of the corresponding light
source 220 in FIG. 8. For example, the light emitting surface of
the light source 220 may overlap a left end portion of the first
pattern 232.
As shown in FIG. 10, the first pattern 232 may be formed at a
location deviated further than the first pattern 232 illustrated in
FIG. 9 toward the light emitting direction. In other words, a
formation area of the first pattern 232 may not overlap a formation
area of the corresponding light source 220. Hence, a left end
portion of the first pattern 232 may be separated from the light
emitting surface of the light source 220 by a predetermined
distance.
As shown in FIG. 11, the first pattern 232 may be formed inside the
resin layer 230. In this case, the middle portion of the first
pattern 232 may be formed to coincide with the middle portion of
the corresponding light source 220 or may be formed at a location
deviated from the middle portion of the corresponding light source
220 toward the light emitting direction in the same manner as FIGS.
8 to 10.
As shown in FIG. 12, the first pattern 232 may be manufactured in a
sheet form. In this case, the pattern layer including the plurality
of first patterns 232 may be formed on the resin layer 230.
For example, after the plurality of first patterns 232 are formed
on one surface of a transparent film 260 through the printing
process, etc. to form the pattern layer, the pattern layer
including the transparent film 260 may be stacked on the resin
layer 230. More specifically, a plurality of dots may be printed on
the transparent film 260 to form the first patterns 232.
As shown in FIG. 13, the plurality of first patterns 232 may be
formed on one surface of the diffusion plate 245 illustrated in
FIG. 3. In this case, the first patterns 232 may be coated on one
surface of the diffusion plate 245, and the diffusion plate 245 may
be formed on the resin layer 230 so that the first patterns 232
contact the resin layer 230.
As a percentage of a formation area of the first pattern 232
increases, an aperture ratio may decrease. Hence, the entire
luminance of light which the backlight unit 200 provides to the
display panel 110 may decrease. The aperture ratio may indicate the
size of an area of the resin layer 230 that is not occupied by the
first pattern 232.
Thus, the aperture ratio of the pattern layer including the first
patterns 232 may be equal to or greater than about 70%, so as to
prevent the degradation of the image quality resulting from an
excessive reduction in the luminance of light provided to the
display panel 110. Namely, the percentage of the area of the resin
layer 230 occupied by the first pattern 232 is equal to or less
about 30% of the total area of the resin layer 230.
As shown in FIG. 14, the first pattern 232 may have a circle or
circular shape or an oval shape around a formation location of the
corresponding light source 220. Other shapes and sizes may be used
for the first pattern 232. The middle portion of the first pattern
232 may be formed at a location deviated slightly from the middle
portion of the corresponding light source 220 toward the light
emitting direction in the same manner as FIGS. 8 to 10.
As shown in FIG. 15, the first pattern 232 may be moved in the
light emitting direction (e.g., an x-axis direction in FIG. 15) in
comparison with that of FIG. 15. Hence, the middle portion of the
first pattern 232 may be formed at a location deviated from the
middle portion of the corresponding light source 220 toward the
light emitting direction by a predetermined distance.
As shown in FIG. 16, the first pattern 232 may be moved toward the
light emitting direction further than the first pattern 232 shown
in FIG. 16. Hence, a portion of the formation area of the light
source 220 may overlap a formation area of the first pattern
232.
As shown in FIG. 17, the first pattern 232 may be moved toward the
light emitting direction further than the first pattern 232 shown
in FIG. 17 and thus may be positioned outside the formation area of
the light source 220. Hence, the formation area of the light source
220 may not overlap a formation area of the first pattern 232.
FIGS. 18 to 21 illustrate various shapes of each first pattern 232.
In FIGS. 18 to 21 the first pattern 232 may be configured by the
plurality of dots or regions, and each dot or each region may
contain a reflection material, for example, metal or metal
oxide.
As shown in FIG. 18, the first pattern 232 may have a circle or
circular shape around the formation location of the light source
220. Other shapes such as a diamond may be used. A reflectance of
the first pattern 232 may decrease as the first pattern 232 extends
from a middle portion 234 of the first pattern 232 to the outwardly
direction. The reflectance of the first pattern 232 may gradually
decrease as the first pattern 232 extends from the middle portion
234 to the outwardly direction, because the number of dots or a
reflectance of a material forming the first pattern 232 decreases
as the first pattern 232 extends from the middle portion 234 to the
outwardly direction.
Further, as the first pattern 232 extends from the middle portion
234 to the outwardly direction, a transmittance or an aperture
ratio of light may increase. Hence, the formation location of the
light source 220, more specifically, the middle portion 234 of the
first pattern 232 corresponding to the middle portion of the light
source 220 may have a maximum reflectance (for example, the middle
portion 234 having the maximum reflectance does not transmit most
of light) and a minimum transmittance or a minimum aperture ratio.
As a result, the hot spot generated when light is concentrated in
the formation area of the light source 220 may be more effectively
prevented.
For example, an aperture ratio of the middle portion of the first
pattern 232 overlapping the light source 220 may be equal to or
less than about 5% so as to prevent the generation of the hot
spot.
In the plurality of dots 233 constituting the first pattern 232, a
distance between the adjacent dots 233 may increase as the first
pattern 232 extends from the middle portion 234 to the outwardly
direction. Hence, as described above, as the first pattern 232
extends from the middle portion 234 to the outwardly direction, the
transmittance or the aperture ratio of the first pattern 232 may
increase while the reflectance of the first pattern 232
decreases.
As shown in FIG. 19, the first pattern 232 may have an oval shape.
The middle portion 234 of the first pattern 232 may coincide with
the middle portion of the corresponding light source 220.
Alternatively, the middle portion 234 of the first pattern 232 may
not coincide with the middle portion of the corresponding light
source 220. In other words, the middle portion 234 of the first
pattern 232 may be formed at a location deviated from the middle
portion of the corresponding light source 220 toward one direction
(for example, a light emitting direction of the corresponding light
source 220) in the same manner as FIGS. 8 to 10.
In this case, as the first pattern 232 extends from a portion 237
of the first pattern 232 corresponding to the middle portion of the
light source 220 to the outwardly direction, the reflectance of the
first pattern 232 may decrease or the transmittance of the first
pattern 232 may increase. That is, the portion 237 of the first
pattern 232 may be positioned at a location deviated from the
middle portion 234 of the first pattern 232 in one direction. The
portion 237 of the first pattern 232 may have a maximum reflectance
or a minimum transmittance.
As shown in FIGS. 20 and 21, the first pattern 232 may have a
rectangle or rectangular shape around the formation location of the
light source 220. As the first pattern 232 extends from the middle
portion to the outwardly direction, a reflectance of the first
pattern 232 may decrease and a transmittance or an aperture ratio
may increase.
The first rectangular pattern 232 shown in FIGS. 20 and 21 may have
the same characteristics as the first pattern 232 shown in FIGS. 18
and 19. For example, an aperture ratio of the middle portion of the
first pattern 232 overlapping the light source 220 may be equal to
or less than 5% so as to prevent the generation of the hot
spot.
Further, as shown in FIGS. 20 and 21, in the plurality of dots 233
constituting the first pattern 232, a distance between the adjacent
dots 233 may increase as the first pattern 232 extends from the
middle portion to the outwardly direction.
In the embodiment of the invention, the first pattern 232 is
configured to include the plurality of dots as shown in FIGS. 18 to
21. However, other configurations may be used. The first pattern
232 may have any configuration as long as the reflectance of the
first pattern 232 decreases and the transmittance or the aperture
ratio of the first pattern 232 increases as the first pattern 232
extends from the middle portion to the outwardly direction.
For example, as the first pattern 232 extends from the middle
portion to the outwardly direction, a concentration of a reflection
material, for example, metal or metal oxide may decrease. Hence,
the reflectance of the first pattern 232 may decrease and the
transmittance or the aperture ratio of the first pattern 232 may
increase. As a result, the concentration of light in an area
adjacent to the light source 220 may be reduced.
As shown in FIG. 22, the first pattern 232 may have a convex shape
protruding toward the light source 220. For example, the first
pattern 232 may have a shape similar to a semicircle. A
cross-sectional shape of the first pattern 232 may have a
semicircle shape or an oval shape protruding toward the light
source 220.
The first pattern 232 having the convex shape may reflect incident
light at various angles. Hence, the first pattern 232 may
uniformize the luminance of light emitted upward from the resin
layer 230 by diffusing more widely light emitted from the light
source 220.
The first pattern 232 may include the reflection material such as
metal or metal oxide as described above. For example, the first
pattern 232 may be formed by forming a pattern on top of the resin
layer 230 by an intaglio method and then filling the intaglio
pattern with a reflection material. Alternatively, the first
pattern 232 may be formed on top of the resin layer 230 by printing
the reflection material on a film type sheet or attaching beads or
metallic particles to the film type sheet and then pressing the
film type sheet onto the resin layer 230.
A cross-sectional shape of the first pattern 232 may have various
shapes protruding toward the light source 220 in addition to a
shape similar to the semicircle shown in FIG. 22. For example, as
shown in FIG. 23, the cross-sectional shape of the first pattern
232 may have a triangular shape protruding toward the light source
220. In this case, the first pattern 232 may have a pyramid shape
or a prism shape.
As shown in FIG. 24, light emitted from the light source 220 may be
diffused by the resin layer 230 and may be emitted upward. Further,
the resin layer 230 can include the plurality of scattering
particles 231 to scatter or refract the upward emitted light,
thereby making the luminance of the upward emitted light more
uniform.
In the embodiment of the invention, another resin layer 235 may be
disposed on top of the resin layer 230. The resin layer 235 may be
formed of the same material as or a different material from the
resin layer 230 and may improve the uniformity of the luminance of
the light of the backlight unit 200 by diffusing the light emitted
upward from the resin layer 230.
The resin layer 235 may be formed of a material having a refractive
index equal to or different from a refractive index of a material
forming the resin layer 230. For example, when the resin layer 235
is formed of a material having a refractive index greater than the
resin layer 230, the resin layer 235 can more widely diffuse the
light emitted from the resin layer 230. In contrast, when the resin
layer 235 is formed of a material having a refractive index less
than the resin layer 230, a reflectance of light, which is emitted
from the resin layer 230 and is reflected on the bottom of the
resin layer 235, can be improved. Hence, the resin layer 235 may
allow the light emitted from the light source 220 to easily travel
along the resin layer 230.
The resin layer 235 may also include a plurality of scattering
particles 236. In this case, a density of the scattering particles
236 of the resin layer 235 may be greater higher than a density of
the scattering particles 231 of the resin layer 230.
As described above, because the resin layer 235 includes the
scattering particles 236 having the density greater than the
scattering particles 231 of the resin layer 230, the resin layer
235 can more widely diffuse the light emitted upward from the resin
layer 230, thereby mating the luminance of the light emitted from
the backlight unit 200 more uniform.
In the embodiment of the invention, the first pattern 232 explained
by referring to FIGS. 7 to 18 may be formed between the resin layer
230 and the resin layer 235 or inside at least one of the resin
layer 230 and the resin layer 235.
As shown in FIG. 24, another pattern layer may be formed on top of
the resin layer 235. The pattern layer on the resin layer 235 may
include a plurality of second patterns 265.
The second patterns 265 on the top of the resin layer 235 may be
reflection patterns capable of reflecting at least a portion of
light emitted from the resin layer 230. Thus, the second patterns
265 may uniformize the luminance of light emitted from the resin
layer 235.
For example, when the light upward emitted from the resin layer 235
is concentrated in a predetermined portion and is observed as light
having a high luminance on the screen, the second patterns 265 may
be formed in a region corresponding to the predetermined portion of
the top of the resin layer 235. Hence, the second patterns 265 may
uniformize the luminance of light emitted from the backlight unit
200 by reducing the luminance of the light in the predetermined
portion.
The second pattern 265 may be formed of titanium dioxide
(TiO.sub.2). In this case, a portion of light emitted from the
resin layer 235 may be reflected downward from the second patterns
265, and a remaining portion of the light emitted from the resin
layer 235 may be transmitted.
As shown in FIG. 25, a thickness h1 of the resin layer 230 may be
less than a height h3 of the light source 220. Hence, the resin
layer 230 may cover a portion of a lower part of the light source
220, and the resin layer 235 may cover a portion of an upper part
of the light source 220.
The resin layer 230 may be formed of resin having a high adhesive
strength. For example, an adhesive strength of the resin layer 230
may be greater than the resin layer 235. Hence, the light emitting
surface of the light source 220 may be strongly attached to the
resin layer 230, and a space between the light emitting surface of
the light source 220 and the resin layer 230 may not be formed.
In the embodiment of the invention, the resin layer 230 may be
formed of silicon-based resin having a high adhesive strength, and
the resin layer 235 may be formed of acrylic resin. In this case,
the refractive index of the resin layer 230 may be greater than the
refractive index of the resin layer 235, and each of the resin
layers 230 and 235 may have the refractive index of approximately
1.4 to 1.6. Further, a thickness h2 of the resin layer 235 may be
less than the height h3 of the light source 220.
As shown in FIG. 26, because the reflection layer 240 is disposed
at the side of the light source 220, a portion of light emitted
from the light source 220 toward the side of the light source 220
may be incident on the reflection layer 240 and may be lost.
The loss of light emitted from the light source 220 decreases an
amount of the light that is incident on the resin layer 230 and
then passes through the resin layer 230. Hence, an amount of light
incident on the display panel 110 from the backlight unit 200 may
decrease. As a result, the luminance of the image displayed on the
display device may be reduced.
Each of the light sources 220 may include a light emitting unit 222
(e.g., LED) emitting light. The light emitting unit 222 may be
positioned at a location separated from the surface of the
substrate 210 by a predetermined height "g".
The thickness "c" of the reflection layer 240 may be equal to or
less than the height "g" of the light emitting unit 222. Hence, the
light source 220 may be positioned above the reflection layer
240.
Accordingly, the thickness "c" of the reflection layer 240 may be
approximately 0.02 mm to 0.08 mm. When the thickness "c" of the
reflection layer 240 is equal to or greater than 0.02 mm, the
reflection layer 240 may have a light reflectance within a reliable
range. When the thickness "c" of the reflection layer 240 is equal
to or less than 0.08 mm, the reflection layer 240 may cover the
light emitting unit 222 of the light source 220. Hence, a loss of
light emitted from the light source 220 may be prevented.
Accordingly, the thickness "c" of the reflection layer 240 may be
approximately 0.02 mm to 0.08 mm, so that the reflection layer 240
improves an incident efficiency of light emitted from the light
source 220 and reflects most of light emitted from the light source
220.
FIG. 27 illustrates an example of the structure of the light source
when viewed from the side of the light source. FIG. 28 illustrates
a horizontal type structure and a vertical type structure of the
light emitting element 325. FIG. 29 illustrates a structure of the
light source when viewed from the front of the light source.
As shown in FIG. 27, the light source 220 may include a plurality
of lead frames 321 and 322, a mold part 324 having a cavity 323, a
light emitting element 325 that is connected to the lead frames 321
and 322 and is mounted in the cavity 323, and an encapsulation
material 326 for filling the cavity 323 in which the light emitting
element 325 is mounted.
The light emitting element 325 may be a light emitting diode (LED)
chip. The LED chip may be configured by a blue LED chip or an
infrared LED chip or may be configured by at least one of a red LED
chip, a green LED chip, a blue LED chip, a yellow green LED chip,
and a white LED chip or a combination thereof.
The light emitting element 325 may be classified into a horizontal
type light emitting element and a vertical type light emitting
element depending on its structure.
As shown in FIG. 28(a), the horizontal type light emitting element
may be positioned on a substrate 340. The substrate 340 may be a
single crystal substrate formed of sapphire, spinel, silicon
carbide, zinc oxide, magnesium oxide, GaN, AlGaN, AlN, NGO
(NdGaO.sub.3), LGO (LiGaO.sub.2), LAO (LaAlO.sub.3), etc.
An n-type semiconductor layer 341 may be positioned on the
substrate 340 and may be formed of, for example, n-GaN. An active
layer 342 may be positioned on the n-type semiconductor layer 341
and may be formed of, for example, InGaN. A p-type semiconductor
layer 343 may be positioned on the active layer 342 and may be
formed of, for example, p-GaN. A p-type electrode 344 may be
positioned on the p-type semiconductor layer 343 and may contain at
least one of chromium (Cr), nickel (Ni), and gold (Au). An n-type
electrode 345 may be positioned on the n-type semiconductor layer
341 and may contain at least one of chromium (Cr), nickel (Ni), and
gold (Au).
As shown in FIG. 28(b), the vertical type light emitting element
may have the structure in which the p-type electrode 345, the
n-type semiconductor layer 341, the active layer 342, and the
p-type semiconductor layer 343 are sequentially stacked on the
n-type electrode 344.
In the light emitting element shown in FIGS. 28(a) and 28(b), when
a voltage is applied to the p-type electrode 344 and the n-type
electrode 345, holes and electrons are combined on the active layer
342. The light emitting element shown in FIGS. 28(a) and 28(b) may
operate by emitting light energy corresponding to a height
difference (i.e., an energy gap) between a conduction band and a
valence band.
Referring again to FIG. 27, the light emitting element 325 may be
packaged in the mold part 324 constituting a body of the light
source 220. For this, the cavity 323 may be formed at one side of
the center of the mold part 324. The mold part 324 may be
injection-molded with a resin material such as polyphtalamide (PPA)
to a press (Cu/Ni/Ag substrate), and the cavity 323 of the mold
part 324 may serve as a reflection cup. The shape or structure of
the mold part 324 may be changed and is not limited thereto.
Each of the lead frames 321 and 322 may penetrate the mold part 324
in a long axis direction of the mold part 324. Ends 327 and 328 of
the lead frames 321 and 322 may be exposed to the outside of the
mold part 324. Herein, when viewed from the bottom of the cavity
323 where the light emitting element 325 is disposed, a
long-direction symmetrical axis of the mold part 324 is referred to
as a long axis and a short-direction symmetrical axis of the mold
part 324 is referred to as a short axis.
A semiconductor device such as a light receiving element and a
protection element may be selectively mounted on the lead frames
321 and 322 in the cavity 323 along with the light emitting element
325. That is, the protection device such as a zener diode for
protecting the light emitting element 325 from electrostatic
discharge (ESD) may be mounted on the lead frames 321 and 322 along
with the light emitting element 325.
The light emitting element 325 may attach to any one lead frame
(for example, the lead frame 322) positioned on the bottom of the
cavity 323, and then may be bonded by wire bonding or flip chip
bonding.
After the light emitting element 325 is connected inside the cavity
323, a mounting area may be filled with the encapsulation material
326. The encapsulation material 326 may include a liquid resin 326a
and a phosphor 326b. The liquid resin 326a may be silicon or an
epoxy material and may be a transparent material. A color of the
phosphor 326b depends on a color of light that the light emitting
element 325 emits. For example, when the light emitting element 325
emits blue light, the phosphor 326b may be yellow.
At least one side of the cavity 323 may be inclined, and the
inclined side of the cavity 323 may serve as a reflection surface
or a reflection layer for selectively reflecting incident light.
The cavity 323 may have a polygonal exterior shape and may have
other shapes other than a polygonal shape.
As shown in FIG. 29, a head part 331 of each light source 220
corresponding to a light emitting part may include a light emitting
surface 332, from which light is actually emitted, and a
non-emitting surface 333, which is a surface other than the light
emitting surface 332 and does not emit light.
More specifically, the light emitting surface 332 of the head part
331 of the light source 220 may be formed by the mold part 324 and
may be defined by the cavity 323 in which the light emitting
element 325 is positioned. For example, the light emitting element
325 may be disposed in the cavity 323 of the mold part 324, and
light emitted from the light emitting element 325 may be emitted
through the light emitting surface 332 surrounded by the mold part
324. Further, the non-emitting surface 333 of the head part 331 of
the light source 220 may be a portion where the mold part 324 is
formed and the light is not emitted.
Further, the light emitting surface 332 of the head part 331 of the
light source 220 may have a shape in which a transverse length is
longer than a longitudinal length. Other shapes may be used for the
light emitting surface 332 of the head part 331. For example, the
light emitting surface 332 may have a rectangular shape.
In addition, the non-emitting surface 333 of the light source 220
may be positioned at upper, lower, left, or right side of the light
emitting surface 332 of the head part 331 of the light source
220.
The ends 327 and 328 of the lead frames 321 and 321 may be first
formed to extend to the outside of the mold part 324 and then may
be secondly formed in one groove of the mold part 324. Hence, the
ends 327 and 328 may be disposed in first and second lead
electrodes 329 and 330. Herein, the number of forming operations
may vary.
The first and second lead electrodes 329 and 330 of the lead frames
321 and 322 may be formed to be received in grooves formed at both
sides of the bottom of the mold part 324. Further, the first and
second lead electrodes 329 and 330 may be formed to have a plate
structure of a predetermined shape and may have a shape in which
solder bonding is easily performed in surface mounting.
The light sources 220 having the above-described configuration may
be disposed on the backlight unit 200.
As shown in FIG. 30, the light sources 220 may be positioned on the
substrate 210, and the reflection layer 230 may be positioned on
the substrate 210 on which the light sources 220 are not
positioned. Further, the resin layer 230 may be positioned on the
substrate 210 to cover the light sources 220 and the reflection
layer 230.
The light sources 220 on the substrate 210 may include the
plurality of lead frames 321 and 322, the mold part 324 having a
cavity 323, the light emitting element 325 that is connected to the
lead frames 321 and 322 and is mounted in the cavity 323, and the
encapsulation material 326 for filling the cavity 323 in which the
light emitting element 325 is mounted.
In particular, the encapsulation material 326 may include the
liquid resin 326a and the phosphor 326b and may be positioned in
the cavity 323. The encapsulation material 326 may protect the
light emitting element 325 and may convert a color of light emitted
from the light emitting element 325. A surface 326c of the
encapsulation material 326 may have a concave lens shape with
respect to an upper part of the cavity 323. The surface 326c of the
encapsulation material 326 may indicate an area where light emitted
from the light emitting element 325 is emitted to the outside of
the encapsulation material 326. A refractive index of light emitted
from the light emitting element 325 may vary depending on a shape
of the surface 326c of the encapsulation material 326.
In the embodiment of the invention, because the surface 326c of the
encapsulation material 326 has the concave lens shape with respect
to the upper part of the cavity 323, light emitted from the light
emitting element 325 may be refracted by the surface 326c of the
encapsulation material 326 and may travel in a direction parallel
to the substrate 210.
As described above, light emitted from the light sources 220 of the
backlight unit 200 according to the embodiment of the invention has
to reach the light source 220 adjacent to each light source 220.
Referring to FIG. 3, light emitted from one light source 220 has to
reach another light source 200 adjacent to the one light source 220
in an emitting direction of the light. Hence, the backlight unit
200 may provide light with the uniform luminance.
Accordingly, in the embodiment of the invention, because light
emitted from the light emitting element 325 is refracted by the
surface 326c of the encapsulation material 326 and travels in the
direction parallel to the substrate 210, light emitted from one
light source 220 is directed towards the neighboring light source
220. As a result, the backlight unit 200 may provide light with the
uniform luminance.
The concave lens-shaped surface 326c of the encapsulation material
326 may have a predetermined concave depth depending on the optical
characteristics. For example, a concave depth "j" of the surface
326c of the encapsulation material 326 may approximately occupy 1%
to 30% of a depth "K" ranging from the top of the light emitting
element 325 to the top of the cavity 323.
When an occupying percentage of the concave depth "j" of the
surface 326c is equal or greater than 1% of the depth "K", light
emitted from the light emitting element 325 may be refracted by the
surface 326c of the encapsulation material 326 and may travel in
the direction parallel to the substrate 210. Hence, light emitted
from the light source 220 may reach the neighboring light source
220, and the backlight unit 200 may provide light with the uniform
luminance. Further, when the occupying percentage of the concave
depth "j" of the surface 326c is equal or less than 30% of the
depth "K", the surface 326c may serve as a buffer so that the
phosphor 326b may convert a color of light emitted from the light
emitting element 325 into another color. Hence, various colors of
light may be sufficiently achieved. For example, when the light
emitting element 325 emits blue light and the phosphor 326b is
yellow, the light source 220 may emit white light because of the
blue light and the yellow phosphor 326b.
As shown in FIG. 30, the resin layer 230 may be formed on the light
source 220 to cover the light source 220. In particular, the
surface 326c of the encapsulation material 326 of the light source
220 may contact the resin layer 230. The resin layer 230 formed of
a resin may have a predetermined adhesive strength. When the
surface 326c of the encapsulation material 326 of the light source
220 has the concave lens shape, an attachable effective area of the
surface 326c of the encapsulation material 326 attached to the
resin layer 230 may increase. Accordingly, an adhesive area between
the resin layer 230 formed of the resin and the surface 326c of the
encapsulation material 326 may increase, and an adhesive strength
between the resin layer 230 and the surface 326c of the
encapsulation material 326 may increase.
As described above, in the embodiment of the invention, because the
surface 326c of the encapsulation material 326 of the light source
220 has the concave lens shape, the linearity of light emitted from
the light source 220 may be improved so that the light may reach
the adjacent light source 220. Further, because the an adhesive
area between the encapsulation material 326 and the resin layer 230
increases, the adhesive strength between the encapsulation material
326 and the resin layer 230 may increase.
As shown in FIG. 31, the light source 220 may be classified into a
lead type light source, a SMD type light source, and a flip-chip
type light source based on a packaging form of the LED chip. The
lead type, SMD type, and flip-chip type light sources may be
applied to the embodiment of the invention. Other types may be
used.
As shown in FIG. 32, a first light source 220 and a second light
source 225 of the plurality of light sources 220 of the backlight
unit 200 may emit light in different directions.
For example, the first light source 220 may emit light in the
lateral direction. For this, the first light source 220 may be
configured using the side view type LED package. The second light
source 225 may emit light in the upward direction. For this, the
second light source 225 may be configured using the top view type
LED package. In other words, the plurality of light sources 220 of
the backlight unit 200 may be configured by combining the side view
type LED packages and the top view type LED packages.
As described above, because the backlight unit 200 is configured by
combining two or more light sources that emit light in different
directions, an increase and a reduction in the luminance of light
in a predetermined area may be prevented. As a result, the
backlight unit 200 may provide light with the uniform luminance to
the display panel 110.
In FIG. 32, the embodiment of the invention is described using a
case where the first light source 220 emitting the light in the
lateral direction and the second light source 225 emitting the
light in the upward direction are disposed adjacent to each other
as an example, but the invention is not limited thereto. For
example, the side view type light sources may be disposed adjacent
to each other or the top view type light sources may be disposed
adjacent to each other.
As shown in FIG. 33, the plurality of light sources 220 and 221 of
the backlight unit 200 may be divided into a plurality of arrays,
for example, a first light source array A1 and a second light
source array A2.
Each of the first light source array A1 and the second light source
array A2 may include a plurality of light source lines each
including light sources. For example, the first light source array
A1 may include a plurality of light source lines L1 each including
at least two light sources, and the second light source array A2
may include a plurality of light source lines L2 each including at
least two light sources.
The plurality of light source lines L1 of the first light source
array A1 and the plurality of light source lines L2 of the second
light source array A2 may be alternately disposed so as to
correspond to the display area of the display panel 110.
In the embodiment of the invention, the first light source array A1
may include odd-numbered light source lines each including at least
two light sources from the top of the plurality of light source
lines, and the second light source array A2 may include
even-numbered light source lines each including at least two light
sources from the top of the plurality of light source lines.
In the embodiment of the invention, the backlight unit 200 may be
configured so that a first light source line L1 of the first light
source array A1 and a second light source line L2 of the second
light source array A2 are disposed adjacent to each other up and
down and the first light source line L1 and the second light source
line L2 are alternately disposed.
Further, the light source 220 of the first light source array A1
and the light source 221 of the second light source array A2 may
emit light in the same direction or in different directions.
As shown in FIG. 34, the backlight unit 200 may include two or more
light sources that emit light in different directions.
In other words, the light sources 220 of the first light source
array A1 and the light sources 221 of the second light source array
A2 may emit light in different directions. For this, a facing
direction of light emitting surfaces of the light sources 220 of
the first light source array A1 face may be different from a facing
direction of light emitting surfaces of the light sources 221 of
the second light source array A2.
More specifically, the light emitting surface of the first light
source, 220 of the first light source array A1 and the light
emitting surface of the second light source 221 of the second light
source array A2 may face in opposite directions or substantially
opposite directions. For example, the first light source 220 of the
first light source array A1 and the second light source 221 of the
second light source array A2 may emit light in opposite directions
or substantially opposite directions. In this case, each of the
light sources of the backlight unit 200 may emit light in the
lateral direction and may be configured by using the side view-type
LED package.
The plurality of light sources of the backlight unit 200 may be
disposed while forming two or more lines. Two or more light sources
on the same line may emit light in the same direction. For example,
light sources adjacent to right and left sides of the first light
source 220 may emit light in the same direction as the first light
source 220, i.e., in the opposite direction of the x-axis
direction. Light sources adjacent to right and left sides of the
second light source 221 may emit light in the same direction as the
second light source 221, i.e., in the x-axis direction.
As described above, the light sources (for example, the first light
source 220 and the second light source 221) disposed adjacent to
each other in a y-axis direction may be configured so that their
light emitting directions are opposite to each other. Hence, the
luminance of light emitted from the light sources may be prevented
from being increased or reduced in a predetermined area of the
backlight unit 200.
For instance, because the light emitted from the first light source
220 travels toward the light source adjacent to the first light
source 220, a luminance of light may be reduced. As a result, the
luminance of the light, which is emitted from the first light
source 220, travels to an area distant from the first light source
220, and is emitted from the area in a direction of the display
panel 110, may be reduced.
Accordingly, because the first light source 220 and the second
light source 221 emit light in the opposite directions in the
embodiment of the invention, a luminance of light emitted from the
first light source 220 and the second light source 221 may be
complementarily prevented from increasing in the area adjacent to
the light source and from being reduced in the area distant from
the light source. Hence, the luminance of light provided by the
backlight unit 200 may be uniformized.
Further, the light sources of the first light source line L1 of the
first light source array A1 and the light sources of the second
light source line L2 of the second light source array A2 may not be
disposed in a straight line in a vertical direction and may be
staggered in the vertical direction. As a result, the uniformity of
light emitted from the backlight unit 200 can be improved. That is,
the first light source 220 of the first light source array A1 and
the second light source 221 of the second light source array A2 may
be disposed adjacent to each other in a diagonal direction or in a
staggered manner.
As shown in FIG. 35, two vertically adjacent light source lines
(for example, the first and second light source lines L1 and L2)
respectively included in the first and second light source arrays
A1 and A2 may be separated from each other by a predetermined
distance d1. In other words, the first light source 220 of the
first light source array A1 and the second light source 221 of the
second light source array A2 may be separated from each other by
the predetermined distance d1 based on the y-axis direction
perpendicular to the x-axis being a light emitting direction.
As the distance d1 between the first and second light source lines
L1 and L2 increases, an area which light emitted from the first
light source 220 or the second light source 221 cannot reach may be
generated. Thus, the luminance of light in the non-reach area may
be greatly reduced. Further, as the distance d1 between the first
and second light source lines L1 and L2 decreases, the light
emitted from the first light source 220 and the light emitted from
the second light source 221 may interfere with each other. In this
case, the division driving efficiency of the light sources may be
deteriorated.
Accordingly, the distance d1 between the adjacent light source
lines (for example, the first and second light source lines L1 and
L2) in a crossing direction of the light emitting direction may be
approximately 5 mm to 22 mm, so as to uniformize the luminance of
the light emitted from the backlight unit 200 while reducing the
interference between the light sources.
Further, the third light source 222 included in the first light
source line L1 of the first light source array A1 may be disposed
adjacent to the first light source 220 in the light emitting
direction. The first light source 220 and the third light source
222 may be separated from each other by a predetermined distance
d2.
A light orientation angle .theta. from the light source and a light
orientation angle .theta.' inside the resin layer 230 may satisfy
the following Equation 1 in accordance with Snell's law. The angle
.alpha. of FIG. 6 may be an example of the light orientation angle
.theta..
.times..times..times..times..times..times..theta.'.times..times..theta..t-
imes..times. ##EQU00001##
Considering that a light emitting portion of the light source is an
air layer (having a refractive index n1 of 1) and the orientation
angle .theta. of light emitted from the light source is generally
60.degree., the light orientation angle .theta.' inside the resin
layer 230 may have a value indicated in the following Equation 2 in
accordance with the above Equation 1.
.times..times..theta.'.times..times..times..degree..times..times..times..-
times. ##EQU00002##
Further, when the resin layer 230 is formed of an acrylic resin
such as polymethyl methacrylate (PMMA), the resin layer 230 has a
refractive index of approximately 1.5. Therefore, the light
orientation angle .theta.' inside the resin layer 230 may be
approximately 35.5.degree. in accordance with the above Equation
2.
As described with reference to the above Equations 1 and 2, the
light orientation angle .theta.' of the light emitted from the
light source in the resin layer 230 may be less than 45.degree.. As
a result, a travelling range of light emitted from the light source
in the y-axis direction may be less than a travelling range of the
light emitted from the light source in the x-axis direction.
Accordingly, the distance d1 between two adjacent light sources
(for example, the first and second light sources 220 and 221) in a
crossing direction of the light emitting direction may be smaller
than the distance d2 between two adjacent light sources (for
example, the first and third light sources 220 and 222) in the
light emitting direction. As a result, the luminance of the light
emitted from the backlight unit 200 can be uniformized.
Considering the distance d1 between the two adjacent light sources
having the above-described range, the distance d2 between two
adjacent light sources (for example, the first and third light
sources 220 and 222) in the light emitting direction may be
approximately 9 mm to 27 mm, so as to uniformize the luminance of
the light emitted from the backlight unit 200 while reducing the
interference between the light sources.
The second light source 221 of the second light source array A2 may
be disposed between the adjacent first and third light sources 220
and 222 included in the first light source array A1.
That is, the second light source 221 may be disposed adjacent to
the first light source 220 and the third light source 222 in the
y-axis direction and may be disposed on a straight line l passing
between the first light source 220 and the third light source 222.
In this case, a distance d3 between the straight line l on which
the second light source 221 is disposed and the first light source
220 may be greater than a distance d4 between the straight line l
and the third light source 222.
Light emitted from the second light source 221 travels in the
opposite direction to a light emitting direction of the third light
source 222, and thus the luminance of light emitted toward the
display panel 110 may be reduced in an area adjacent to the third
light source 222.
Accordingly, in the embodiment of the invention, because the second
light source 221 is disposed closer to the third light source 222
than to the first light source 220, the reduction in the luminance
of light in the area adjacent to the third light source 222 may be
compensated using an increase in the luminance of light in the area
adjacent to the second light source 221.
At least one of the plurality of light sources 220 included in the
backlight unit 200 may emit light in a direction slightly inclined
to a horizontal direction (i.e., the x-axis direction).
For example, as shown in FIG. 36, the light emitting surface of the
light sources 220 and 221 may face upward or downward at a
predetermined angle from the x-axis.
Further, as shown in FIG. 37, the light sources 220, 221, and 224
included in the light source lines L1, L2, and L3 may be staggered.
For example, the light sources included in the light source lines
L1, L3, and L2 of the first light source array A1 and the light
sources included in the light source lines L2, L1, and L3 of the
second light source array A2 may be staggered.
Accordingly, the light sources included in the light source lines
L1, L3, and L2 of the first light source array A1 and the light
sources included in the light source lines L2, L1, and L3 of the
second light source array A2 may be alternatively disposed.
Further, the light sources 220, 221, and 224 may be the same light
source. However, the light sources 220, 221, and 224 may emit light
in different directions or may have different characteristics, for
example, the type, the size, and the direction, if desired.
As shown in FIG. 38, the backlight unit according to the embodiment
of the invention may further include a plurality of diffusion
patterns 241 that allow light emitted from the light source 220 on
the reflection layer 240 to easily travel to a light source 225
adjacent to the light source 220. The plurality of diffusion
patterns 241 may diffuse or refract light emitted from the light
source 220.
More specifically, as shown in FIG. 39, the backlight unit 200
according to the embodiment of the invention may further include at
least two light sources, each of which emits light in a different
direction. For example, the backlight unit 200 may include a first
light source 225 and a second light source 226 that emit light in a
direction parallel to the x-axis direction (i.e., in a lateral
direction). The first light source 225 and the second light source
226 may be positioned adjacent to each other in the x-axis
direction. The backlight unit 200 may further include a third light
source 227 and a fourth light source 228 that are positioned
perpendicular to the x-axis direction and emit light in the
opposite direction of a light emitting direction of the first and
second light sources 225 and 226. In other words, lines on which
the first and second light sources 225 and 226 are arranged and
lines on which the third and fourth light sources 227 and 228 are
arranged may be arranged to cross one another.
Accordingly, because the light emitting direction of the first and
second light sources 225 and 226 is opposite to the light emitting
direction of the third and fourth light sources 227 and 228 in the
embodiment of the invention, an increase or a reduction in the
luminance of light in a predetermined area of the backlight unit
200 may be prevented. In this case, as light emitted from the first
light source 225 travels to the second light source 226, a
luminance of the light emitted from the first light source 225 may
be reduced. Hence, a luminance of light, which is emitted from the
first light source 225, travels to an area distant from the first
light source 225, and is emitted from the area in a direction of
the display panel, may be reduced.
Accordingly, the embodiment of the invention, the plurality of
diffusion patterns 241 may be disposed between the first light
source 225 and the second light source 226 to diffuse or refract
light emitted from the first light source 225. Hence, the plurality
of diffusion patterns 241 may allow the backlight unit 200 to
provide light with the uniform luminance.
The diffusion patterns 241 may contain at least one of metal and
metal oxide that are a reflection material. For example, the
diffusion patterns 241 may contain metal or metal oxide having a
high reflectance, such as aluminum (Al), silver (Ag), gold (Au),
and titanium dioxide (TiO.sub.2). In this case, the diffusion
patterns 241 may be formed by depositing or coating the metal or
the metal oxide on the substrate 210 or by printing a metal ink on
the substrate 210. The deposition method may use a heat deposition
method, an evaporation method, or a vacuum deposition method such
as a sputtering method. The coating method or the printing method
may use a gravure coating method or a silk screen method.
Further, the diffusion patterns 241 may have a color having the
high brightness, for example, a color close to white so as to
improve a reflection or refraction effect of the diffusion patterns
241.
The diffusion patterns 241 may include a plurality of dots formed
of the above material. For example, the diffusion patterns 241 may
include a plurality of dots having a circle plane shape, an oval
plane shape, or a polygon plane shape.
A density of the diffusion patterns 241 may increase as the
diffusion patterns 241 extend from the first light source 225
towards the second light source 226 as shown in FIGS. 38 and 39.
Hence, a reduction in the luminance of light emitted upward from an
area distant from the first light source 225 (i.e., an area around
a back surface of the second light source 226) may be prevented. As
a result, the luminance of light provided by the backlight unit 200
may be uniformized.
For example, a distance between the two adjacent diffusion patterns
241 each including the dots may increase as the diffusion patterns
241 extend from the light emitting surface of the first light
source 225 to the second light source 226. Hence, while light
emitted from the first light source 225 travels to the second light
source 226, the light is diffused or refracted. As a result, the
luminance of the light may be uniformized.
In particular, the diffusion patterns 241 may hardly exist in an
area adjacent to the first light source 225. Hence, the light
emitted from the first light source 225 is totally reflected by the
reflection layer 240 in a non-formation area of the diffusion
patterns 241 to travel and is diffused or refracted in a formation
area of the diffusion patterns 241. As a result, the luminance of
light in the entire area of the backlight unit including an area
adjacent to the second light source 226 may be uniformized.
The plurality of diffusion patterns 241 may be disposed between the
third light source 227 and the fourth light source 228 that emit
light in the opposite direction of the light emitting direction of
the first and second light sources 225 and 226.
The density of the diffusion patterns 241 may increase as the
diffusion patterns 241 extend from the light emitting surface of
the third light source 227 to the fourth light source 228 in the
same manner as the first and second light sources 225 and 226, so
as to allow the light to propagate more evenly or uniformly through
the area between the light sources. Further, a distance between the
two adjacent diffusion patterns 241 among the plurality of
diffusion patterns 241 between the third light source 227 and the
fourth light source 228 may decrease as the diffusion patterns 241
extend from the light emitting surface of the third light source
227 to the fourth light source 228.
The third light source 227 is diagonally positioned across the
first light source 225 in the light emitting direction of the first
light source 225, and the plurality of diffusion patterns 241 may
be disposed on a diagonal line between the first light source 220
and the second light source 221 in a line. Because the first and
third light sources 225 and 227 emit light in the opposite
directions, the luminance of light may increase in an overlapping
area between light emitted from the first light source 225 and
light emitted from the third light source 227. Thus, the plurality
of diffusion patterns 241 disposed on the diagonal line between the
first light source 225 and the third light source 227 may prevent
an increase in the luminance of light in the overlapping area of
light.
Accordingly, as shown in FIG. 39, a plane shape of the diffusion
patterns 241 between the first and second light sources 225 and 226
may be symmetrical to a plane shape of the diffusion patterns 241
between the third and fourth light sources 227 and 228. For
example, the plane shape of the diffusion patterns 241 between the
first and second light sources 225 and 226 or between the third and
fourth light sources 227 and 228 may be a fan shape.
Because the fan-shaped diffusion patterns 241 are disposed based on
the orientation angle of about 200.degree. of light emitted from
the light source, the fan-shaped diffusion patterns 241 efficiently
transfer and diffuse the light emitted from the light source.
Hence, the entire luminance of light provided by the backlight unit
may be uniformized.
As shown in FIG. 40, the substrate 210, the plurality of light
sources 220 on the substrate 210, the resin layer 230 covering the
plurality of light sources 220, the reflection layer 240 on the
substrate 210, and the plurality of diffusion patterns 241 on the
reflection layer 240 may constitute an optical assembly 10 in the
same manner as FIGS. 2-26 and 32-39. The backlight unit 200 may be
configured using the plurality of optical assemblies 10.
The plurality of optical assemblies 10 constituting the backlight
unit 200 may be arranged in a matrix structure of N.times.M, where
N and M are a natural number equal to or greater than 2. For
example, as shown in FIG. 40, 21 optical assemblies 10 of the
backlight unit 200 may be arranged in a matrix structure of
7.times.3. Since the structure of the optical assemblies shown in
FIG. 40 is an example, other matrix structures may be used based on
the screen size of the display device.
For example, in the 47-inch display device, 240 optical assemblies
having a matrix structure of 24.times.10 may constitute the
backlight unit 200.
The optical assemblies 10 may be independently manufactured and may
be positioned adjacent to one another, thereby forming a module
type backlight unit. The module type backlight unit may provide
light to the display panel 110.
The backlight unit 200 according to the embodiments of the
invention may be driven in a full driving manner such as global
dimming or a partial driving manner such as local dimming and
impulsive driving. The backlight unit 200 may be driven in various
driving manners depending on a circuit design. As a result, in the
embodiment of the invention, a color contrast ratio can increase,
and also the image quality can be improved because a bright image
and a dark image may be clearly displayed on the screen of the
display device.
In other words, the backlight unit 200 may be divided into a
plurality of division driving regions (blocks) to selectively and
independently operate each of the regions according to dimming and
other operations. Each of these regions can be selectively and
independently driven so that the light sources in one region may be
turned on while the light sources in another region may be turned
off, or vice versa. Further, the light sources in one region of the
backlight unit may be dimmed while the light sources in another
region of the backlight unit may emit brighter light. In an
example, the backlight unit 200 may reduce a luminance of a dark
image and increase a luminance of a bright image based on a
relation between a luminance of each of the division driving
regions and a luminance of a video signal, thereby improving the
contrast ratio and the definition.
For example, some of the optical assemblies 10 may upward provide
light by independently driving only some of the light sources 220.
For this, the light sources 220 included in the each of the optical
assemblies 10 may be independently controlled.
An area of the display panel 110 corresponding to one optical
assembly 10 may be selectively and independently divided into two
or more blocks. The display panel 110 and the backlight unit 200
may be separately driven in each block.
Because the plurality of optical assemblies 10 are assembled as
described above to configure the backlight unit 200, a
manufacturing process of the backlight unit 200 may be simplified
and a manufacturing loss generated in the manufacturing process may
be minimized. Hence, productivity of the backlight unit 200 may be
improved. Further, the optical assemblies 10 may be applied to the
backlight unit having various sizes by standardizing the optical
assemblies 10 and mass-producing the standardized optical
assemblies 10.
Furthermore, when one of the plurality of optical assemblies 10 of
the backlight unit 200 is defective, only the defective optical
assembly 10 (or that region) is replaced without replacing all of
the optical assemblies 10 of the backlight unit 200. Therefore, a
replacing work is easy and the part replacing cost is saved.
As shown in FIG. 41, the display panel 110 including a first
substrate 111, a second substrate 112, an upper polarizing plate
160a, and a lower polarizing plate 160a may closely adhere to the
backlight unit 200 including the substrate 210, the plurality of
light sources 220, and the resin layer 230. For example, an
adhesive layer 170 may be formed between the backlight unit 200 and
the display panel 110 to adhesively fix the backlight unit 200 to
the bottom of the display panel 110.
More specifically, the top of the backlight unit 200 may adhere to
the bottom of the lower polarizing plate 160b using the adhesive
layer 170. The backlight unit 200 may further include the diffusion
plate 245 on the resin layer 230. A plurality of optical sheets
(not shown) may be formed between the diffusion plate 245 and the
adhesive layer 170.
Further, a frame 135 may be disposed on the bottom of the backlight
unit 200 and may closely adhere to the bottom of the substrate
210.
The display device may include a display module, e.g., a driver for
supplying a driving voltage and a power to the display panel 110
and the backlight unit 200. For example, the plurality of light
sources 220 of the backlight unit 200 may be driven using the
driving voltage supplied by the driver to emit light.
The driver may include a driving controller 141, a power supply
unit 143, and a main board (not shown). The driver may be disposed
and fixed on a driver chassis 145 positioned on the frame 135, so
that the driver may be stably supported and fixed.
In the embodiment of the invention, a first connector 310 may be
formed on the back surface of the substrate 210. For this, a hole
350 for inserting the first connector 310 may be formed in the
frame 135.
The first connector 310 may electrically connect the power supply
unit 143 to the light source 220. Hence, the driving voltage
supplied by the power supply unit 143 may be supplied to the light
source 220.
For example, the first connector 310 may be formed on the bottom of
the substrate 210 and may be connected to the power supply unit 143
using a first cable 410. Hence, the first connector 310 may be used
to transfer the driving voltage supplied by the power supply unit
143 through the first cable 410 to the light source 220.
An electrode pattern (not shown), for example, a carbon nanotube
electrode pattern may be formed on the top of the substrate 210.
The electrode formed on the top of the substrate 210 may contact
the electrode formed in the light source 220 and may electrically
connect the light source 220 with the first connector 310.
Further, the display device may include the driving controller 141
for controlling a drive of the display panel 110 and a drive of the
backlight unit 200. For example, the driving controller 141 may be
a timing controller.
The timing controller may control a driving timing of the display
panel 110. More specifically, the timing controller may generate a
control signal for controlling a driving timing of each of a data
driver (not shown), a gamma voltage generator (not shown), and a
gate driver (not shown) that are included in the display panel 110
and may supply the control signal to the display panel 110.
The timing controller may synchronize with a drive of the display
panel 110 and may supply a signal for controlling driving timing of
the light sources 220 to the backlight unit 200, so that the
backlight unit 200, more specifically, the light sources 220
operate.
As shown in FIG. 41, the driving controller 141 may be fixed to the
driver chassis 145 positioned on the frame 135, so that the driving
controller 141 may be stably supported and fixed.
In the embodiment of the invention, a second connector 320 may be
formed on the substrate 210. For this, a hole 350 for inserting the
second connector 320 may be formed in the frame 135.
The second connector 320 may electrically connect the driving
controller 141 with the substrate 210, thereby allowing a control
signal output from the driving controller 141 to be supplied to the
substrate 210.
For example, the second connector 320 may be formed on the bottom
of the substrate 210 and may be connected to the driving controller
141 using a second cable 420. Hence, the second connector 320 may
be used to transfer a control signal supplied by the driving
controller 141 through the second cable 420 to the substrate
210.
A light source driver (not shown) may be formed on the substrate
210. The light source driver may drive the light sources 220 using
the control signal supplied from the driving controller 141 through
the second connector 320.
The driving controller 141 and the power supply unit 143 may be
covered by a back cover 150 and may be protected from the
outside.
The configuration of the display device shown in FIG. 41 is just
one embodiment of the invention. Therefore, the location or the
numbers of each of the driving controller 141, the power supply
unit 143, the first and second connector 310 and 320, and the first
and second cables 420 and 430 may be changed, if necessary.
FIGS. 42 to 46 illustrate a disposition relationship between a
frame, a driver, and a back cover. Structures and components
identical or equivalent to those illustrated in FIGS. 1 to 41 are
designated with the same reference numerals, and a further
description may be briefly made or may be entirely omitted.
As shown in FIG. 42, the driver 140 for operating the display panel
110 or supplying the driving signal to the backlight unit 200 may
be positioned on the bottom of the frame 135. Further, the back
cover 150 may not cover the entire area of the frame 135 and may
cover a partial area of the frame 135.
In other words, the driver 140 may be positioned in a predetermined
area of the frame 135, and the back cover 150 may be positioned in
a predetermined area of the frame 135 at a location corresponding
to the driver 140.
For example, as shown in FIG. 42, the frame 135 may have a
rectangular plate shape, and the driver 140 may be positioned on a
second long side LS2 of the frame 135.
In the embodiment of the invention, the second long side LS2 may be
opposite to a first long side LS1 and may be positioned adjacent to
a first short side SS1 and a second short side SS2. The first long
side LS1 of the frame 135 may be referred to as a first region, and
the second long side LS2 of the frame 135 may be referred to as a
second region.
In this instance, as shown in FIGS. 42 and 43, a distance L1
between the first region LS1 of the frame 135 and the driver 140
may be longer than a distance L2 between the second region LS2 of
the frame 135 and the driver 140. Further, a distance L10 between
the first region LS1 of the frame 135 and the back cover 150 may be
longer than a distance L20 between the second region LS2 of the
frame 135 and the back cover 150.
The second region LS2 of the frame 135 may be adjacent to a support
(not shown) for supporting the display panel 110.
As above, when the driver 140 positioned in the rear of the frame
135 is positioned adjacent to the second region LS2 of the frame
135, the back cover 150 may be positioned adjacent to the second
region LS2 of the frame 135.
Further, the driver 140 may be positioned in an overlap area A10
between the frame 135 and the back cover 150.
When the driver 140 and the back cover 150 are positioned adjacent
to the second region LS2 of the frame 135, the display panel 110,
the backlight unit 200, and the front cover 130 are combined with
one another.
In the combined structure shown in FIG. 44, an adhesive layer 4400
may be positioned between the frame 135 and the backlight unit 200.
In this instance, the backlight unit 200 may be closer to the frame
135.
A connection relationship between the driver 140 and the display
panel 110 is described with reference to FIGS. 45 and 46. FIG. 45
is a partial cross-sectional view illustrating the connection
relationship, and FIG. 46 is a perspective view illustrating a
combined state of the display device.
In FIGS. 45 and 46, an end of each of wires 500 is electrically
connected to a switching element (not shown) provided on the lower
substrate of the display panel 110. Other end of each wire 500
extends to the frame 135 via the side of the display panel 110
and/or the backlight unit 200.
A hole 13a is formed in the frame 135. The wires 500 pass through
the hole 13a and extend to the outside of the display device.
The driver 140 is screw-combined with the back surface of the frame
135 around the hole 13a. Thus, the wires 500 passing through the
hole 13a are connected to a connector C of the driver 140, and the
driver 140 is connected to the lower substrate of the display panel
110.
The driver 140 is connected to the display panel 110 and/or the
backlight unit 200 through the wires 500 and is fixed to the back
surface of the frame 135. The driver 140 may be fixed to the back
surface of the frame 135 using a screw.
The back cover 150 covers the driver 140 and is fixed to the frame
135, thereby protecting the driver 140 from an external impact.
FIGS. 47 to 54 illustrate a display device including a heat
dissipation member. Structures and components identical or
equivalent to those illustrated in FIGS. 1 to 46 are designated
with the same reference numerals, and a further description may be
briefly made or may be entirely omitted.
As shown in FIGS. 47 and 48, a display device according to the
embodiment of the invention may include a frame 520 on which a
backlight unit 510 is disposed, a driver chassis 540 that is
positioned on a back surface of the frame 520 to fix the driver
550, and a back cover 560 covering the driver 550.
As described above, the backlight unit 510 may include a plurality
of light sources 515 arranged in a predetermined form.
A plurality of holes 525 may be formed in the frame 520, so that
the backlight unit 510 is connected to the driver 550 positioned on
the back surface of the frame 520. A heat dissipation member 530
may be positioned between the backlight unit 510 and the frame 520
(i.e., the surface of the frame 520 opposite the backlight unit
510).
The heat dissipation member 530 may be formed in a sheet form by
embedding metal beads 532 in a support layer 531. In other words,
the metal beads 532 are embedded in the support layer 531 to form
the heat dissipation sheet 530. Various forms of metal including a
mesh or a powder in addition to the bead form may be used. Because
the heat dissipation sheet 530 is manufactured in a roll form, the
heat dissipation sheet 530 has the particle size suitable for the
flexibility of the heat dissipation sheet 530 for the roll
form.
The metal beads 532 of the heat dissipation member 530 are
uniformly distributed into the support layer 531. The heat
dissipation member 530 including the metal beads 532 is
manufactured to be very thin. When the heat dissipation member 530
is thick, it is difficult to manufacture the heat dissipation
member 530 of the roll form.
The support layer 531 may be formed using a thermoplastic resin
such as vinyl acetate resin, polyvinyl alcohol resin, vinyl
chloride resin, polyvinyl acetate resin, acrylic resin, saturated
polyester resin, polyamide resin, and polyethylene resin. A reason
to form the support layer 531 using the thermoplastic resin is to
easily manufacturer the heat dissipation sheet 530 in the roll
form.
The metal beads 532 may be formed of metal having high thermal
conductivity, for example, gold (Au), silver (Ag), copper (Cu), and
aluminum (Al). The heat generated in the light sources 515 of the
backlight unit 510 or the heat generated by an operation of the
driver 550 may be uniformly distributed into the heat dissipation
member 530 through the metal beads 532 formed of metal having the
high thermal conductivity.
The heat generated by the operation of the backlight unit 510 or
the driver 550 may be uniformly distributed into the heat
dissipation member 530 formed by embedding or inserting the metal
beads 532 formed of metal having the high thermal conductivity into
the support layer 531 formed of the thermoplastic resin. Hence, the
heat dissipation effect of the display device may be improved.
The backlight unit 510 including the plurality of light sources 515
positioned adjacent to the frame 520 requires heat dissipation
means for dissipating the heat generated in the light sources 515.
In particular, because the backlight unit 510 is directly attached
to the display panel 110 as shown in FIG. 41, the display panel 110
may be adversely affected by the heat generated in the backlight
unit 510.
Accordingly, the display device according to the embodiment of the
invention includes the heat dissipation member 530 between the
backlight unit 510 and the frame 520, thereby increasing the heat
dissipation effect of the backlight unit 510.
The heat dissipation member 530 manufactured in the sheet form may
be attached to the frame 520. In this instance, an adhesive may be
applied to one surface of the heat dissipation sheet 530, and the
heat dissipation sheet 530 may be attached to the frame 520 using
the adhesive.
FIGS. 47 and 48 illustrate one heat dissipation sheet 530 attached
to the frame 520. However, the plurality of heat dissipation sheets
530 may be attached to the frame 520, and the plurality of heat
dissipation sheets 530 each having a stripe shape may be attached
to the frame 520.
Alternatively, the liquid heat dissipation member 530 may be
applied to the frame 520. The liquid heat dissipation member 530
may be formed by inserting the metal beads 532 into the support
layer 531 and then coating the metal beads 532.
As shown in FIGS. 49 and 50, the heat dissipation member 530
according to the embodiment of the invention may be positioned
between the frame 520 and the driver 550.
More specifically, the heat dissipation member 530 may be
positioned on the back surface of the frame 520. The frame 520 may
be formed of a conductive material, for example, aluminum. Because
the backlight unit 510 received in the frame 520 is positioned
close to one surface of the frame 520, the heat generated in the
light sources of the backlight unit 510 may be transferred to the
frame 520. Accordingly, the heat dissipation effect of the
backlight unit 510 may be improved through the heat dissipation
member 530 positioned on the back surface of the frame 520.
The driver 550 may be positioned on the frame 520 using the driver
chassis 540 and requires an element for dissipating the heat
generated when the driver 550 is driven. Accordingly, in the
embodiment of the invention, the heat dissipation member 530 may be
positioned on the back surface of the frame 520 adjacent to the
driver 550, thereby improving the heat dissipation effect of the
driver 550 as well as the backlight unit 510.
As shown in FIGS. 51 and 52, the heat dissipation member 530
according to the embodiment of the invention may be positioned
between the driver 550 and the back cover 560.
More specifically, the heat dissipation member 530 may be
positioned on one surface of the back cover 560, i.e., on one
surface of the back cover 560 opposite the driver 550. The driver
550 requires an element for dissipating the heat generated when the
driver 550 covered by the back cover 560 is driven.
In particular, in the embodiment of the invention, when the heat
generated in the driver 550 is transferred to the backlight unit
510 through the frame 520, a component formed of a resin among
components of the backlight unit 510 may be damaged by the heat.
Accordingly, in the embodiment of the invention, the heat
dissipation member 530 may be positioned on one surface of the back
cover 560 covering the driver 550, thereby improving the heat
dissipation effect of the driver 550.
As shown in FIGS. 53 and 54, the heat dissipation member 530
according to the embodiment of the invention may be positioned on
an external surface of the back cover 560 covering the driver
550.
As described above, the heat dissipation member 530 for dissipating
the heat generated when the driver 550 is driven may be positioned
on the external surface of the back cover 560 covering the driver
550. Hence, the backlight unit 510 may be prevented from being
damaged by the heat that is generated in the driver 550 and is
transferred to the backlight unit 510 through the frame 520.
FIGS. 55 to 68 illustrate a substrate including a plurality of
subsidiary substrates. Structures and components identical or
equivalent to those illustrated in FIGS. 1 to 54 are designated
with the same reference numerals, and a further description may be
briefly made or may be entirely omitted.
As shown in FIG. 55, a frame 135 may be positioned in the rear of a
backlight unit 200, and an adhesive layer 900 may be positioned
between the backlight unit 200 and the frame 135. Preferably, the
adhesive layer 900 may be positioned between a back surface of a
substrate 210 included in the backlight unit 200 and the frame
135.
The adhesive layer 900 may attach the substrate 210 of the
backlight unit 200 to the frame 135. Hence, the backlight unit 200
may be more closely attached to the frame 135. As a result, the
thickness of the display device may decrease.
Further, the adhesive layer 900 may transfer heat generated in
light sources 220 positioned on the substrate 210 to the frame 135,
thereby preventing an excessive increase in a temperature of the
light sources 220. Because the adhesive layer 900 may transfer the
heat generated in the backlight unit 200 to the frame 135, the
adhesive layer 900 may be referred to as a thermal transfer
layer.
It may be preferable that the adhesive layer 900 contains a thermal
conductive material so as to transfer the heat generated in the
light sources 220 to the frame 135. The thermal conductive material
of the adhesive layer 900 is not particularly limited. Examples of
the thermal conductive material of the adhesive layer 900 include a
metal material and a carbon material. In the embodiment of the
invention, it may be preferable that the adhesive layer 900 is
formed using the metal material in consideration of the
manufacturing cost and the ease of forming.
Further, the thermal conductive material of the adhesive layer 900
may be manufactured in the form of particles and may be distributed
into the adhesive layer 900. For example, as shown in FIG. 56, the
adhesive layer 900 may include metal particles 910.
As above, the adhesive layer 900 may include the metal particles
910 formed of the adhesive material and the thermal conductive
material, so as to transfer the heat generated in the light sources
220 to the frame 135 while attaching the backlight unit 200 to the
frame 135.
Unlike the embodiment of the invention, as shown in FIG. 57, the
adhesive layer 900 between the backlight unit 200 and the frame 135
may be omitted, and the backlight unit 200 and the frame 135 may be
spaced apart from each other at a predetermined distance.
In the structure illustrated in FIG. 57, because it is difficult to
transfer the heat generated in the light sources 220 to the frame
135, the temperature of the light sources 220 may excessively
increase. As a result, the light generation efficiency of the light
sources 220 may be reduced.
Furthermore, when a resin layer 230 covering the light sources 220
is formed on the substrate 210, the entire thickness of the display
device may decrease by closely adhering the resin layer 230 to
other functional layer (for example, an optical sheet) positioned
on the resin layer 230. However, the resin layer 230 may block the
dissipation of the heat generated in the light sources 220, thereby
excessively increasing the temperature of the light sources
220.
Furthermore, in the structure illustrated in FIG. 57, the thickness
of the display device may increase because of a space between the
backlight unit 200 and the frame 135.
Alternatively, as shown in FIG. 58, the adhesive layer 900 between
the backlight unit 200 and the frame 135 may be omitted, and the
backlight unit 200 may be positioned directly on the frame 135.
When the structure illustrated in FIG. 48 is applied to the FIG.
58, the backlight unit 200 may contact a portion of the frame 135.
However, because the substrate 210 of the backlight unit 200 and
the frame 135 are in not a liquid state but a solid state, the
backlight unit 200 cannot completely contact the frame 135. Hence,
because it is difficult to transfer the heat generated in the light
sources 220 to the frame 135, the temperature of the light sources
220 may excessively increase.
Further, in the structure illustrated in FIG. 48, because the
backlight unit 200 does not closely adhere to the frame 135, a
space between the backlight unit 200 and the frame 135 may be
formed. Hence, the thickness of the display device may increase
On the other hand, in the structure illustrated in FIG. 55
according to the embodiment of the invention, the adhesive layer
900 may be positioned between the backlight unit 200 and the frame
135, and the backlight unit 200 may closely adhere to the frame
135. Hence, the thickness of the display device may decrease.
Further, because the heat generated in the light sources 220 is
easily transferred to the frame 135, an excessive increase in the
temperature of the light sources 220 may be prevented. As a result,
a reduction in the efficiency of the light sources 220 may be
prevented.
Further, in the structure illustrated in FIG. 55 according to the
embodiment of the invention, the resin layer 230 covering the light
sources 220 may be formed on the substrate 210. Therefore, even if
it is difficult to dissipate the heat generated in the light
sources 220 upward the light sources 220, the excessive increase in
the temperature of the light sources 220 may be prevented by
transferring the heat generated in the light sources 220 to the
frame 135.
The adhesive layer 900 may be divided into a plurality of parts.
For example, as shown in FIG. 59, the adhesive layer 900 may be
divided into a first subsidiary adhesive layer 901, a second
subsidiary adhesive layer 902, a third subsidiary adhesive layer
903, and a fourth subsidiary adhesive layer 904. The first to
fourth subsidiary adhesive layers 901-904 may contain an adhesive
material. The first to fourth subsidiary adhesive layers 901-904
may be positioned parallel to one another to be spaced apart from
one another at a predetermined distance.
As above, when the plurality of subsidiary adhesive layers 901-904
are formed between the substrate 210 and the frame 135, the
manufacturing process may be easily performed and the manufacturing
cost may be reduced.
For example, the adhesive layer 900 may be formed by laminating a
relatively narrow adhesive sheet, which is cut to correspond to a
length of a short side SS of the substrate 210, on the back surface
of the substrate 210. The first to fourth subsidiary adhesive
layers 901-904 formed using the above-described laminating method
may be positioned parallel to the short side SS of the substrate
210 to be spaced apart from one another at a predetermined
distance.
Alternatively, as shown in FIG. 60, the adhesive layer 900 may be
divided into a fifth subsidiary adhesive layer 905, a sixth
subsidiary adhesive layer 906, and a seventh subsidiary adhesive
layer 907. The fifth to seventh subsidiary adhesive layers 905-907
may be positioned parallel to a long side LS of the substrate 210
to be spaced apart from one another at a predetermined
distance.
When the adhesive layer 900 is divided into the plurality of
subsidiary adhesive layers, an air layer may be formed between the
substrate 210 and the frame 135. For example, as shown in FIG. 61,
an air layer 1500 may be formed between the first subsidiary
adhesive layer 901 and the second subsidiary adhesive layer
902.
Holes 1510 may be formed in a formation area of the air layer 1500.
The heat generated in the light sources 220 may more easily
dissipated by circulating the air through the holes 1510.
Alternatively, as shown in FIG. 62, the adhesive layer 900 may be
formed in an area corresponding to the light sources 220. In this
instance, the light sources 220 may correspond to the adhesive
layers 900, respectively. Further, the adhesive layers 900 may be
positioned to be spaced apart from one another.
As shown in FIG. 63, one substrate 210 may be divided into a
plurality of subsidiary substrates 211-214. For example, the
substrate 210 may include a first subsidiary substrate 211, a
second subsidiary substrate 212, a third subsidiary substrate 213,
and a fourth subsidiary substrate 214.
In this instance, as shown in FIG. 64, the plurality of light
sources 220 may be disposed on each of the first to fourth
subsidiary substrates 211-214, and then the first to fourth
subsidiary substrates 211-214 may be combined parallel to one
another to form one substrate 210.
When there is a defect in any one subsidiary substrate of the
substrate 210 formed by combining the plurality of subsidiary
substrates, only the defective subsidiary substrate may be
replaced, and the remaining normal subsidiary substrates may be
continuously used. Hence, the material used may be saved, and the
manufacturing cost may be reduced.
As above, when the substrate 210 is divided into the plurality of
subsidiary substrates, the adhesive layer 900 may be formed between
the two adjacent subsidiary substrates.
For example, as shown FIG. 65, the adhesive layer 900 may include a
first subsidiary adhesive layer 2000, a second subsidiary adhesive
layer 2010, and a third subsidiary adhesive layer 2020, that are
positioned to be spaced apart from one another, and the substrate
210 may include the first to fourth subsidiary substrates 211-214.
In this instance, the first subsidiary adhesive layer 2000 may be
disposed to commonly overlap the first subsidiary substrate 211 and
the second subsidiary substrate 212, the second subsidiary adhesive
layer 2010 may be disposed to commonly overlap the second
subsidiary substrate 212 and the third subsidiary substrate 213,
and the third subsidiary adhesive layer 2020 may be disposed to
commonly overlap the third subsidiary substrate 213 and the fourth
subsidiary substrate 214.
In other words, the structure illustrated in FIG. 65 may be
referred to as the structure for connecting the two subsidiary
substrates using one subsidiary adhesive layer. Hence, while the
subsidiary adhesive layer closely adheres the backlight unit 200 to
the frame 135 and transfer the heat generated in the light sources
220 to the frame 135, the subsidiary adhesive layer may connect the
two separated subsidiary substrates.
Alternatively, as shown in FIG. 66, one subsidiary substrate may
correspond to one subsidiary adhesive layer. For example, the
adhesive layer 900 may include a first subsidiary adhesive layer
2100, a second subsidiary adhesive layer 2110, a third subsidiary
adhesive layer 2120, and a fourth subsidiary adhesive layer 2130,
that are positioned to be spaced apart from one another, and the
substrate 210 may include the first to fourth subsidiary substrates
211-214. In this instance, the first subsidiary adhesive layer 2100
may be positioned on a back surface of the first subsidiary
substrate 211, the second subsidiary adhesive layer 2110 may be
positioned on a back surface of the second subsidiary substrate
212, the third subsidiary adhesive layer 2120 may be positioned on
a back surface of the third subsidiary substrate 213, and the
fourth subsidiary adhesive layer 2130 may be positioned on a back
surface of the fourth subsidiary substrate 214.
The first to fourth subsidiary substrates 211-214 may be
manufactured by respectively disposing the first to fourth
subsidiary adhesive layers 2100-2130 on the back surfaces of the
first to fourth subsidiary substrates 211-214 and then connecting
the first to fourth subsidiary substrates 211-214.
Alternatively, a distance between the two adjacent subsidiary
adhesive layers may vary.
For example, as shown in FIG. 67, the adhesive layer 900 may
include a first subsidiary adhesive layer 2240, a second subsidiary
adhesive layer 2250, a third subsidiary adhesive layer 2260, and a
fourth subsidiary adhesive layer 2270, that are positioned to be
spaced apart from one another, and the substrate 210 may include
the first to fourth subsidiary substrates 211-214. Further, a
plurality of connectors may be disposed on the first to fourth
subsidiary substrates 211-214. In other words, a first connector
2200 may be disposed on the first subsidiary substrate 211, a
second connector 2210 may be disposed on the second subsidiary
substrate 212, a third connector 2220 may be disposed on the third
subsidiary substrate 213, and a fourth connector 2230 may be
disposed on the fourth subsidiary substrate 214.
Each of the first to fourth connectors 2200-2230 may be connected
to a cable (not shown) for electrically connecting the light
sources 220 positioned on the first to fourth subsidiary substrates
211-214 to an external driving circuit (not shown).
Further, a plurality of subsidiary thermal transfer units may be
positioned on the back surfaces of the first to fourth subsidiary
substrates 211-214 without overlapping the first to fourth
connectors 2200-2230. For example, as shown in FIG. 67, the first
and second connectors 2200 and 2210 may be disposed between a first
subsidiary thermal transfer unit 2240 and a second subsidiary
thermal transfer unit 2250, and the third and fourth connectors
2220 and 2230 may be disposed between a third subsidiary thermal
transfer unit 2260 and a fourth subsidiary thermal transfer unit
2270. Hence, a distance W1 between the first subsidiary thermal
transfer unit 2240 and the second subsidiary thermal transfer unit
2250 may be greater than a distance W2 between the second
subsidiary thermal transfer unit 2250 and the third subsidiary
thermal transfer unit 2260.
Alternatively, a length of one of the plurality of subsidiary
adhesive layers may be different from lengths of other subsidiary
adhesive layers. For example, as shown in FIG. 68, the adhesive
layer 900 may include a first subsidiary adhesive layer 2300, a
second subsidiary adhesive layer 2310, a third subsidiary adhesive
layer 2320, a fourth subsidiary adhesive layer 2330, and a fifth
subsidiary adhesive layer 2340, that are positioned to be spaced
apart from one another, and the substrate 210 may include the first
to fourth subsidiary substrates 211-214. Further, a plurality of
connectors 2200, 2210, 2220, and 2230 may be disposed on the first
to fourth subsidiary substrates 211-214, respectively.
Further, at least one of the first to fifth subsidiary adhesive
layers 2300-2340 may be disposed at a location overlapping the
connectors 2200-2230 at a location corresponding to the connectors
2200-2230, i.e., in a longitudinal direction.
For example, as shown in FIG. 68, the second subsidiary adhesive
layer 2310 may be disposed at a location overlapping the first and
second connectors 2200 and 2210 in a longitudinal direction, and
the fourth subsidiary adhesive layer 2330 may be disposed at a
location overlapping the third and fourth connectors 2220 and 2230
in a longitudinal direction. Hence, a distance L2 of each of the
second subsidiary adhesive layer 2310 and the fourth subsidiary
adhesive layer 2330 may be less than a distance L1 of each of the
first subsidiary adhesive layer 2300, the third subsidiary adhesive
layer 2320, and the fifth subsidiary adhesive layer 2340.
Further, a width of at least one of the first to fifth subsidiary
adhesive layers 2300-2340 may be different from widths of other
subsidiary adhesive layers. For example, as shown in FIG. 68, a
width W20 of the third subsidiary adhesive layer 2320 may be
greater than a width W10 of the first subsidiary adhesive layer
2300.
Although embodiments have been described with reference to a number
of illustrative embodiments thereof, it should be understood that
numerous other modifications and embodiments can be devised by
those skilled in the art that will fall within the scope of the
principles of this disclosure. More particularly, various
variations and modifications are possible in the component parts
and/or arrangements of the subject combination arrangement within
the scope of the disclosure, the drawings and the appended claims.
In addition to variations and modifications in the component parts
and/or arrangements, alternative uses will also be apparent to
those skilled in the art.
* * * * *