U.S. patent application number 14/537522 was filed with the patent office on 2015-05-14 for organic light emitting display panel and organic light emitting display device including the same.
This patent application is currently assigned to LG DISPLAY CO., LTD.. The applicant listed for this patent is LG DISPLAY CO., LTD.. Invention is credited to SO HYUN KIM, YOUNG JU PARK.
Application Number | 20150129856 14/537522 |
Document ID | / |
Family ID | 51357858 |
Filed Date | 2015-05-14 |
United States Patent
Application |
20150129856 |
Kind Code |
A1 |
KIM; SO HYUN ; et
al. |
May 14, 2015 |
ORGANIC LIGHT EMITTING DISPLAY PANEL AND ORGANIC LIGHT EMITTING
DISPLAY DEVICE INCLUDING THE SAME
Abstract
Discussed is an organic light emitting display panel. The
organic light emitting display panel includes a plurality of unit
pixels which each include first to third sub-pixels having
different colors. The plurality of unit pixels, which each include
first to third driving transistors respectively connected to the
first to third sub-pixels, a first contact hole that connects the
first sub-pixel to the first driving transistor, a second contact
hole that connects the second sub-pixel to the second driving
transistor, and a third contact hole that connects the third
sub-pixel to the third driving transistor, are arranged in a matrix
type.
Inventors: |
KIM; SO HYUN; (PAJU-SI,
KR) ; PARK; YOUNG JU; (SEOUL, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
LG DISPLAY CO., LTD. |
SEOUL |
|
KR |
|
|
Assignee: |
LG DISPLAY CO., LTD.
SEOUL
KR
|
Family ID: |
51357858 |
Appl. No.: |
14/537522 |
Filed: |
November 10, 2014 |
Current U.S.
Class: |
257/40 |
Current CPC
Class: |
H01L 27/3216 20130101;
H01L 27/3246 20130101; H01L 27/3218 20130101; H01L 27/3248
20130101 |
Class at
Publication: |
257/40 |
International
Class: |
H01L 27/32 20060101
H01L027/32 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 13, 2013 |
KR |
10-2013-0137372 |
Claims
1. An organic light emitting display panel, comprising: a plurality
of unit pixels, each including first to third sub-pixels having
different colors, wherein each of the plurality of unit pixels
includes first to third driving transistors respectively connected
to the first to third sub-pixels, a first contact hole that
connects the first sub-pixel to the first driving transistor, a
second contact hole that connects the second sub-pixel to the
second driving transistor, and a third contact hole that connects
the third sub-pixel to the third driving transistor, and the
plurality of unit pixels are arranged in a matrix, a plurality of
the first sub-pixels are arranged adjacent to each other in unit
pixels which are adjacent to each other in a first direction, a
plurality of the third sub-pixels are arranged adjacent to each
other at a boundary of respectively adjacent two unit pixels,
wherein the two adjacent unit pixels form a unit pixel pair, and a
plurality of the second sub-pixels, wherein the second sub-pixel of
a pixel unit is adjacent to the third sub-pixel in the unit pixel
in the first direction, and is arranged farther apart from the
boundary of the two adjacent unit pixels of the unit pixel pair
than the third sub-pixels of the unit pixel pair.
2. The organic light emitting display panel of claim 1, wherein the
first to third contact holes are disposed adjacent to a boundary of
the unit pixels which are adjacent to each other in the first
direction.
3. The organic light emitting display panel of claim 1, wherein the
first contact hole is disposed between the plurality of the first
sub-pixels which are adjacent to each other in the first direction,
and wherein the second and third contact holes may be disposed
between the second sub-pixel and the third sub-pixel of a
respective pixel unit.
4. The organic light emitting display panel of claim 1, wherein the
first sub-pixel comprises an upper sub-pixel and a lower sub-pixel
in the unit pixel, wherein the first contact hole is disposed
between the upper sub-pixel and the lower sub-pixel of the pixel
unit, and wherein the second and third contact holes are disposed
between the second sub-pixel and the third sub-pixel of the pixel
unit.
5. The organic light emitting display panel of claim 4, wherein the
first to third contact holes are arranged in parallel in a second
direction, wherein the second direction is perpendicular to the
first direction.
6. The organic light emitting display panel of claim 5, wherein the
first to third sub-pixels are disposed adjacent to one of first to
third sub-pixels, included in an adjacent unit pixel, at a boundary
of unit pixels.
7. The organic light emitting display panel of claim 1, wherein the
first sub-pixel is greater than the second and third sub-pixels,
and comprises a blue organic emission layer.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the Korean Patent
Application No. 10-2013-0137372 filed on Nov. 13, 2013, which is
hereby incorporated by reference as if fully set forth herein.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates to an organic light emitting
display panel, and more particularly, to an organic light emitting
display panel in which an arrangement structure of sub-pixels is
changed to widen a width of an organic emission layer.
[0004] 2. Discussion of the Related Art
[0005] A flat panel display (FPD) device is applied to various
electronic devices such as portable phones, tablet personal
computers (PCs), notebook computers, monitors, etc. Examples of the
FPD device include liquid crystal display (LCD) devices, plasma
display panel (PDP) devices, organic light emitting display
devices, etc. Recently, electrophoretic display (EPD) devices are
being widely used as one type of the FPD device.
[0006] Among the display devices, the organic light emitting
display devices use a self-emitting element, and thus have a fast
response time, high emission efficiency, high luminance, and a
broad viewing angle.
[0007] The organic light emitting display devices may be configured
in a top emission type where an organic light emitting diode (OLED)
is formed on a lower substrate, and light emitted from the OLED is
output to the outside through an upper substrate.
[0008] Moreover, the organic light emitting display devices may be
configured in a bottom emission type where the OLED is formed on
the lower substrate, and the light emitted from the OLED is
transferred to the lower substrate.
[0009] Recently, organic light emitting display devices that emits
light in a dual emission type where the bottom emission type is
combined with the top emission type are being developed.
[0010] FIG. 1 is a first exemplary diagram illustrating a related
art organic light emitting display panel 10, and particularly, is
an exemplary diagram illustrating an organic light emitting display
device in which a plurality of sub-pixels are arranged in a stripe
structure.
[0011] A plurality of sub-pixels 11 applied to the related art
organic light emitting display panel 10, as illustrated in FIG. 1,
are arranged in the stripe structure.
[0012] A plurality of contact holes (PLN Hole) 13 illustrated in
FIG. 1 may be formed in the organic light emitting display panel 10
so that a driving transistor, e.g., a driving thin film transistor
(TFT), used to drive an OLED 12 is electrically connected to the
OLED 12.
[0013] For example, the driving TFT (not shown) is insulated from
the OLED 12 by an insulation layer (not shown). Therefore, the
contact hole 13 may be formed on the insulation layer so that the
driving TFT and the OLED 12 separated from each other by the
insulation layer are electrically connected.
[0014] In this case, as illustrated in FIG. 1, the contact holes 13
are respectively formed at the same positions of lower ends of all
the sub-pixels 11.
[0015] In the related art organic light emitting display panel 10,
since the contact holes are respectively formed at the same
positions of the lower ends of the sub-pixels 11, enhancement of an
aperture ratio is limited when the sub-pixels 11 are formed by
using a fine metal mask (FMM). That is, since each of the contact
holes 13 is disposed adjacent to a boundary between adjacent
sub-pixels, an emission area of each sub-pixel is reduced. Also,
the fine metal mask has a pattern so as to correspond to one
sub-pixel, and it is required to manufacture a smaller pattern when
manufacturing a high-resolution organic light emitting display
panel. However, there is a limitation in manufacturing a smaller
pattern. The fine metal mask is a mask that is used to deposit an
organic emission layer in units of a pixel in an organic light
emitting display panel, and has a fine pattern. Therefore, the
pattern of the fine metal mask should be further reduced in the
high-resolution organic light emitting display panel, and for this
reason, it is difficult to form a structure of the sub-pixels
illustrated in FIG. 1. For example, in an organic light emitting
display panel having a high resolution of 300 ppi or more, it is
difficult to form the structure of the sub-pixels illustrated in
FIG. 1.
[0016] That is, a resolution of organic light emitting display
panels becomes increasingly higher, but due to the above-described
structure of the sub-pixels of the related art, it is difficult to
manufacture the high-resolution organic light emitting display
panel.
[0017] To provide an additional description, as the resolution of
an organic light emitting display panel increases, a size of a
sub-pixel is reduced. In this case, the thickness of the fine metal
mask used to manufacture the organic light emitting display panel
is limited, and since a distance between ribs of the fine metal
mask is insufficient, a desired aperture ratio cannot be realized
in the organic light emitting display panel using the structure of
sub-pixels of the related art. That is, in the process of
evaporating an organic emission layer by using an evaporation
process, due to a limitation of a method of manufacturing the fine
metal mask, it is difficult to manufacture an organic light
emitting display panel having a high resolution.
SUMMARY OF THE INVENTION
[0018] Accordingly, the present invention is directed to provide an
organic light emitting display panel and an organic light emitting
display device including the same that substantially obviate one or
more problems due to limitations and disadvantages of the related
art.
[0019] An aspect of the present invention is directed to provide a
new arrangement structure of sub-pixels in which an organic light
emitting display panel, which has the same resolution as that of a
related art organic light emitting display panel because a size of
a unit pixel is the same, expresses a better sense of color than
the related art organic light emitting display panel.
[0020] Another aspect of the present invention is directed to
provide an arrangement structure of sub-pixels which enables a
high-resolution unit pixel to be formed.
[0021] Additional advantages and features of the invention will be
set forth in part in the description which follows and in part will
become apparent to those having ordinary skill in the art upon
examination of the following or may be learned from practice of the
invention. The objectives and other advantages of the invention may
be realized and attained by the structure particularly pointed out
in the written description and claims hereof as well as the
appended drawings.
[0022] To achieve these and other advantages and in accordance with
the purpose of the invention, as embodied and broadly described
herein, there is provided an organic light emitting display panel
including a plurality of unit pixel which each include first to
third sub-pixels having different colors, wherein the plurality of
unit pixels each include first to third driving transistors
respectively connected to the first to third sub-pixels, a first
contact hole that connects the first sub-pixel to the first driving
transistor, a second contact hole that connects the second
sub-pixel to the second driving transistor, and a third contact
hole that connects the third sub-pixel to the third driving
transistor, and are arranged in a matrix type. Here, a plurality of
the first sub-pixels are arranged adjacent to each other in unit
pixels which are adjacent to each other in a first direction, a
plurality of the third sub-pixels are arranged adjacent to each
other at a boundary of respectively adjacent two unit pixels,
wherein the two adjacent unit pixels form a unit pixel pair, and a
plurality of second sub-pixels, wherein the second sub-pixel of a
pixel unit is adjacent to the third sub-pixel in the unit pixel in
the first direction, and is arranged farther apart from the
boundary of the two adjacent unit pixels of the unit pixel pair
than the third sub-pixels of the unit pixel pair. In this case, in
unit pixels which are adjacent to each other in the vertical
direction, sub-pixels configuring each unit pixel may be disposed
adjacent to sub-pixels of the same color. Accordingly, the present
invention can enhance a sense of color.
[0023] The first to third contact holes may be disposed adjacent to
a boundary of the unit pixels which are adjacent to each other in
the first direction. In this case, the contact holes may be
disposed in one row in a certain direction, thereby enabling a fine
metal mask to be easily manufactured.
[0024] The first contact hole may be disposed between a plurality
of the sub-pixels which are adjacent to each other in the first
direction, and the second and third contact holes may be disposed
between the second sub-pixel and the third sub-pixel of a
respective pixel unit. In this case, the second and third contact
holes configuring a unit pixel may be disposed adjacent to second
and third contact holes configuring an adjacent unit pixel, and a
fine metal mask for enhancing an aperture ratio can be
manufactured. In particular, in manufacturing a high-resolution
organic light emitting display panel, the manufacturing of the fine
metal mask is limited, but the present invention overcomes the
limitation, and enables a finer sub-pixel to be manufactured.
[0025] The first sub-pixel comprises an upper sub-pixel and a lower
sub-pixel in the unit pixel, the first contact hole may be disposed
between the upper sub-pixel and the lower sub-pixel of the pixel
unit, and the second and third contact holes may be disposed
between the second sub-pixel and the third sub-pixel of the pixel
unit.
[0026] The first to third contact holes may be arranged in parallel
in a second direction, wherein the second direction is
perpendicular to the first direction.
[0027] The first to third sub-pixels may be disposed adjacent to
one of first to third sub-pixels, included in an adjacent unit
pixel, at a boundary of unit pixels. In this case, sub-pixels
included in a unit pixel may be disposed in parallel, and thus, a
mask can be easily manufactured. Also, first to third sub-pixels
included in a unit pixel may be disposed adjacent to first to third
sub-pixels adjacent thereto. Accordingly, the present invention can
contribute to increase a width of an emission area.
[0028] The first sub-pixel may be greater than the second and third
sub-pixels, and may include a blue organic emission layer. In this
case, even though an emission efficiency of a blue sub-pixel is
lower than that of red and green sub-pixels in an organic light
emitting display panel, since the blue sub-pixel is greater than
the red and green sub-pixels, the red, green, and blue sub-pixels
can have the same luminance.
[0029] It is to be understood that both the foregoing general
description and the following detailed description of the present
invention are exemplary and explanatory and are intended to provide
further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] The accompanying drawings, which are included to provide a
further understanding of the invention and are incorporated in and
constitute a part of this application, illustrate embodiments of
the invention and together with the description serve to explain
the principle of the invention. In the drawings:
[0031] FIG. 1 is a first exemplary diagram illustrating a related
art organic light emitting display panel;
[0032] FIG. 2 is a block diagram of an organic light emitting
display device according to an embodiment of the present
invention;
[0033] FIG. 3 is an exemplary diagram illustrating a plane
structure of an organic light emitting display panel according to a
first embodiment of the present invention;
[0034] FIG. 4 is an exemplary diagram illustrating a plane
structure of an organic light emitting display panel according to a
second embodiment of the present invention;
[0035] FIG. 5 is an exemplary diagram illustrating a plane
structure of an organic light emitting display panel according to a
third embodiment of the present invention;
[0036] FIG. 6 is an exemplary diagram illustrating a
cross-sectional surface taken along line X-X' of the organic light
emitting display panel of FIG. 5; and
[0037] FIG. 7 is an exemplary diagram illustrating an example of an
interval between OLEDs in the organic light emitting display panel
of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0038] Reference will now be made in detail to the exemplary
embodiments of the present invention, examples of which are
illustrated in the accompanying drawings. Wherever possible, the
same reference numbers will be used throughout the drawings to
refer to the same or like parts.
[0039] Hereinafter, embodiments of the present invention will be
described in detail with reference to the accompanying
drawings.
[0040] FIG. 2 is a block diagram of an organic light emitting
display device according to an embodiment of the present
invention.
[0041] The embodiments of the present invention relate to a pixel
arrangement structure of an organic light emitting display panel.
Generally, since there is a limitation in manufacturing a fine
metal mask, there is a limitation in manufacturing a
high-resolution organic light emitting display panel by using an
evaporation process. To solve such a limitation, the embodied
present invention provides an organic light emitting display panel,
in which an arrangement structure of sub-pixels is changed to
realize a high resolution, and an organic light emitting display
device including the same.
[0042] In an organic light emitting display panel having a related
art pixel structure, in order to electrically connect a driving
thin film transistor (TFT) and an organic light emitting diode
(OLED) which are separated from each other by an insulation layer,
a contact hole formed in the insulation layer is formed adjacent to
a boundary between vertically adjacent unit pixels. Therefore, when
an organic emission layer is deposited by using a fine metal mask,
there is a risk in which the organic emission layer is deposited in
the contact hole, and for this reason, a plurality of the organic
emission layers cannot be deposited at one time. However, according
to an embodiment of the present invention, the plurality of organic
emission layers may be deposited at one time.
[0043] An organic light emitting display device according to an
embodiment of the present invention, as illustrated in FIG. 2,
includes an organic light emitting display panel 100 including a
plurality of sub-pixels 110 and a driver that drives the organic
light emitting display panel 100. All the components of the device
are operatively coupled and configured. Here, in the organic light
emitting display panel 100, a sub-pixel P is formed in each of
intersection areas between a plurality of gate lines GL1 to GLg and
a plurality of data lines DL1 to DLd. Also, the driver includes a
gate driver 200 that sequentially supplies a gate pulse to the gate
lines GL1 to GLg formed in the organic light emitting display panel
100, a data driver 300 that respectively supplies data voltages to
the data lines DL1 to DLd formed in the organic light emitting
display panel 100, and a timing controller 400 that controls
functions of the gate driver 200 and the data driver 300.
[0044] First, in the organic light emitting display panel 100, a
sub-pixel (P) 110 is formed in each of the intersection areas
between the plurality of gate lines GL and the plurality of data
lines DL. The sub-pixel 110 is for expressing red, green or blue,
and a blue sub-pixel, a red sub-pixel, and a green sub-pixel
configure one unit pixel. That is, the one unit pixel includes the
blue sub-pixel, the red sub-pixel, and the green sub-pixel.
[0045] The sub-pixel 110, as illustrated in an enlarged circle 1 of
FIG. 2, may include an organic light emitting diode OLED, at least
two or more transistors TR1 and TR2 which are connected to a data
line DL and a gate line GL to control the organic light emitting
diode OLED, and a storage capacitor Cst. Hereinafter, a first
transistor TR1 is referred to as a switching TFT, and a second
transistor 112 is referred to as a driving TFT.
[0046] First, the organic light emitting diode 113 includes a first
electrode, an organic emission layer formed on the first electrode,
and a second electrode formed on the organic emission layer. Here,
the first and second electrodes may respectively be an anode
electrode and a cathode electrode, or may respectively be a cathode
electrode and an anode electrode.
[0047] The anode electrode of the organic light emitting diode OLED
is connected to a first power source VDD, and the cathode electrode
is connected to a second power source VSS. The organic light
emitting diode OLED emits light having certain luminance in
correspondence with a current supplied from the second transistor
112.
[0048] Second, when the gate pulse is supplied to the gate line GL,
various circuits included in the sub-pixel 110 control an amount of
current supplied to the organic light emitting diode OLED in order
for a current, corresponding to an image signal supplied to the
data line DL, to be supplied to the organic light emitting diode
OLED.
[0049] To this end, the sub-pixel 110 includes: the driving TFT 112
connected between the first power source VDD and the organic light
emitting diode 113; the switching TFT TR1 connected to the driving
TFT 112, the data line DL, and the gate line GL; and a storage
capacitor Cst connected between a gate electrode of the driving TFT
112 and the organic light emitting diode 113. In FIG. 2, a
sub-pixel according to an embodiment of the present invention is
schematically illustrated, and particularly, the sub-pixel 100
including two transistors and one capacitor is illustrated.
However, the sub-pixel 100 may be configured in various types with
various compensation transistors.
[0050] Moreover, as illustrated in FIG. 2, the anode electrode or
cathode electrode of the organic light emitting diode 113 is
connected to the driving TFT 112 through a connection line 111. The
connection line 111 may be, for example, a line connected to the
anode electrode or a line which is formed as one body with the
anode electrode.
[0051] A detailed configuration of one or more examples of the
organic light emitting display panel 100 will be described in
detail with reference to FIGS. 3 to 7.
[0052] The timing controller 400 outputs a gate control signal GCS
for controlling the data driver 200 and a data control signal DCS
for controlling the data driver 300 by using a vertical sync
signal, a horizontal sync signal, and a clock signal which are
supplied from an external system.
[0053] Moreover, the timing controller 400 samples input video data
input from the external system, realigns the sampled video data,
and supplies the realigned digital image data RGB to the data
driver 300.
[0054] That is, the timing controller 400 realigns the input video
data supplied from the external system, and transfers the realigned
digital image data to the data driver 300. The timing controller
400 generates the gate control signal GCS for controlling the data
driver 200 and the data control signal DCS for controlling the data
driver 300 by using the clock signal, the vertical sync signal, the
horizontal sync signal, and a data enable signal which are supplied
from an external system, and respectively transfers the gate
control signal GCS and the data control signal DCS to the gate
driver 200 and the data driver 300. Here, the clock signal, the
vertical sync signal, and the horizontal sync signal are referred
to as a timing signal.
[0055] To this end, the timing controller 400 includes: a receiver
that receives the various signals such as the input video data
supplied from the external system; an image data processor that
realigns the input video data among the signals received by the
receiver so as to match a structure of the panel 110, and generates
the realigned digital image data; a control signal generator that
generates the gate control signal GCS and the data control signal
DCS for respectively controlling the gate driver 200 and the data
driver 300 by using the signals received from the receiver; and a
transferor that outputs the gate control signal GCS to the gate
driver 200 and outputs the data control signal DCS and the image
data, generated by the image data processor, to the data driver
300.
[0056] The data driver 300 converts the image data, input from the
timing controller 400, into analog data voltages and respectively
supplies the data voltages for one horizontal line to the data
lines at every one horizontal period in which the scan pulse is
supplied to a corresponding gate line. That is, the data driver 300
converts the image data into the data voltages by using gamma
voltages supplied from a gamma voltage generator, and respectively
outputs the data voltages to the data lines.
[0057] The data driver 300 shifts a source start pulse (SSP) input
from the timing controller 400 according to a source shift clock
(SSC) to generate a sampling signal. The data driver 300 latches
pixel data RGB (image data) according to the sampling signal to
convert the image data into data voltages, and respectively
supplies the data voltages to the data lines in units of a
horizontal line in response to a source output enable signal
(SOE).
[0058] To this end, the data driver 300 may include a shift
register, a latch, a digital-to-analog converter (DAC), and an
output buffer.
[0059] The shift register outputs the sampling signal by using
control signals received from the timing controller 400.
[0060] The latch latches the digital image data Data that are
sequentially received from the timing controller 400, and
simultaneously outputs the digital image data to the DAC.
[0061] The DAC simultaneously converts the image data Data,
transferred from the latch, into positive or negative data
voltages, and outputs the positive or negative data voltages. That
is, the DAC converts the image data into the positive or negative
data voltages according to a polarity control signal transferred
from the timing controller 400, by using the gamma voltages
supplied from the gamma voltage generator (not shown), and
respectively outputs the positive or negative data voltages to the
data lines.
[0062] The output buffer outputs the data voltages, transferred
from the DAC, to the data lines DL1 of the organic light emitting
display panel 100 according to the source output enable signal
(SOE) transferred from the timing controller 400.
[0063] The gate driver 200 sequentially supplies a gate pulse to
the gate lines GL1 to GLg of the organic light emitting panel 100
in response to the gate control signal GCS input from the timing
controller 400. Therefore, the switching TFTs of respective
sub-pixels 110 on a corresponding horizontal line receiving the
gate pulse are turned on, and an image is output to the sub-pixels
110.
[0064] That is, the gate driver 200 shifts a gate start pulse (GSP)
transferred from the timing controller 400 according to a gate
shift clock (GSC), and sequentially supplies the gate pulse having
a gate-on voltage (Von) to the gate lines GL1 to GLg. During the
other period in which the gate pulse having the gate-on voltage
(Von) is not supplied, the gate driver 200 supplies a gate-off
voltage (Voff) to the gate lines GL1 to GLg.
[0065] The gate driver 200 may be provided independently from the
organic light emitting display panel 100, and may be implemented in
a type which is electrically connectable to the organic light
emitting display panel 100 in various methods. However, the gate
driver 200 may be implemented in a gate-in panel (GIP) type which
is equipped in the organic light emitting display panel 100. In
this case, the gate control signals for controlling the gate driver
200 may include a start signal (VST) and a gate clock (GCLK).
[0066] Moreover, in the above description, the data driver 300, the
gate driver 200, and the timing controller 400 are illustrated as
being separately provided, but at least one selected from the data
driver 300 and the gate driver 200 may be provided as one body with
the timing controller 400.
[0067] FIG. 3 is an exemplary diagram illustrating a plane
structure of an organic light emitting display panel according to a
first embodiment of the present invention, and particularly,
illustrates a configuration of each of sub-pixels configuring the
organic light emitting display panel.
[0068] The organic light emitting display panel according to the
first embodiment of the present invention, as illustrated in FIG.
3, includes a first sub-pixel 110a, a second sub-pixel 110b, and a
third sub-pixel 110c which have different colors. In the organic
light emitting display panel according to the first embodiment of
the present invention, a plurality of unit pixels 120, which each
include first to third driving TFTs respectively connected to the
first to third sub-pixels 110a to 110c, a first contact hole 131
that connects the first sub-pixel 110a to the first driving TFT, a
second contact hole 132 that connects the second sub-pixel 110b to
the second driving TFT, and a third contact hole 133 that connects
the third sub-pixel 110c to the third driving TFT, are arranged in
a matrix type. A plurality of the first sub-pixels 110a are
arranged in a stripe type in unit pixels which are adjacent to each
other in a vertical direction (a first direction), and a plurality
of the third sub-pixels 110c are arranged adjacent to each other at
a boundary of adjacent unit pixels. The second sub-pixel 110b is
adjacent to the third sub-pixel 110c in a unit pixel, and is
arranged farther apart from the boundary than the third sub-pixel
110c.
[0069] In particular, in the first embodiment of the present
invention, the first to third contact holes 131 to 133 are disposed
adjacent to a boundary of the unit pixels 120 which are adjacent to
each other in the vertical direction (the first direction).
[0070] FIG. 4 is an exemplary diagram illustrating a plane
structure of an organic light emitting display panel according to a
second embodiment of the present invention, and particularly,
illustrates a configuration of each of sub-pixels configuring the
organic light emitting display panel.
[0071] The organic light emitting display panel according to the
second embodiment of the present invention, as illustrated in FIG.
4, includes a first sub-pixel 110a, a second sub-pixel 110b, and a
third sub-pixel 110c which have different colors. In the organic
light emitting display panel according to the second embodiment of
the present invention, a plurality of unit pixels 120, which each
include first to third driving TFTs respectively connected to the
first to third sub-pixels 110a to 110c, a first contact hole 131
that connects the first sub-pixel 110a to the first driving TFT, a
second contact hole 132 that connects the second sub-pixel 110b to
the second driving TFT, and a third contact hole 133 that connects
the third sub-pixel 110c to the third driving TFT, are arranged in
a matrix type. A plurality of the first sub-pixels 110a are
arranged in a stripe type in unit pixels which are adjacent to each
other in a vertical direction (a first direction), and a plurality
of the third sub-pixels 110c are arranged adjacent to each other at
a boundary of adjacent unit pixels. The second sub-pixel 110b is
adjacent to the third sub-pixel 110c in a unit pixel, and is
arranged farther apart from the boundary than the third sub-pixel
110c.
[0072] In particular, in the second embodiment of the present
invention, the first contact hole 131 is disposed between a
plurality of the sub-pixels 110a which are adjacent to each other
in the vertical direction, and the second and third contact holes
132 and 133 are disposed between the second sub-pixel 110b and the
third sub-pixel 110c within a respective unit pixel.
[0073] FIG. 5 is an exemplary diagram illustrating a plane
structure of an organic light emitting display panel according to a
third embodiment of the present invention, and particularly,
illustrates a configuration of each of sub-pixels configuring the
organic light emitting display panel.
[0074] The organic light emitting display panel according to the
third embodiment of the present invention, as illustrated in FIG.
5, includes a first sub-pixel 110a, a second sub-pixel 110b, and a
third sub-pixel 110c which have different colors. In the organic
light emitting display panel according to the third embodiment of
the present invention, a plurality of unit pixels 120, which each
include first to third driving TFTs respectively connected to the
first to third sub-pixels 110a to 110c, a first contact hole 131
that connects the first sub-pixel 110a to the first driving TFT, a
second contact hole 132 that connects the second sub-pixel 110b to
the second driving TFT, and a third contact hole 133 that connects
the third sub-pixel 110c to the third driving TFT, are arranged in
a matrix type. A plurality of the first sub-pixels 110a are
arranged in a stripe type in unit pixels which are adjacent to each
other in a vertical direction (a first direction), and a plurality
of the third sub-pixels 110c are arranged adjacent to each other at
a boundary of adjacent unit pixels. The second sub-pixel 110b is
adjacent to the third sub-pixel 110c in a unit pixel, and is
arranged farther apart from the boundary than the third sub-pixel
110c.
[0075] In particular, in the third embodiment of the present
invention, in order for a high-resolution pixel structure to be
applied, a bank is formed in the first sub-pixel 110a by using a
slit mask, and the first sub-pixel 110a is divided into two
segments. Also, in the third embodiment of the present invention, a
bank is formed between the second and third sub-pixels 110b and
110c which are disposed in a vertical direction.
[0076] The organic light emitting display panel according to the
third embodiment of the present invention, as illustrated in FIG.
5, includes the plurality of unit pixels 120, and each of the unit
pixels 120 includes a blue sub-pixel for expressing blue, a red
sub-pixel for expressing red, and a green sub-pixel for expressing
green.
[0077] For example, each of the unit pixels 120 includes three
sub-pixels 110a to 110c, which may be the blue sub-pixel 110a, the
red sub-pixel 110b, and the green sub-pixel 110c.
[0078] White and black may be expressed by a combination of the
sub-pixels 110.
[0079] Hereinafter, for convenience of description, the organic
light emitting display panel according to the embodiments of the
present invention will be described on the assumption that the blue
sub-pixel is the blue sub-pixel 110a, the red sub-pixel is the red
sub-pixel 110b, and the green sub-pixel is the green sub-pixel
110c.
[0080] The first sub-pixel 110a includes a first organic light
emitting diode OLED1 that expresses blue B, the second sub-pixel
110b includes a second organic light emitting diode OLED2 that
expresses red, and the third sub-pixel 110c includes a third
organic light emitting diode OLED3 that expresses green. Here, the
first organic light emitting diode OLED1 may be divided into a
first sub organic light emitting diode OLED1.sub.--1 and a second
sub organic light emitting diode OLED1.sub.--2. That is, the first
sub-pixel 110a including the first organic light emitting diode
OLED1 is divided into two sub-pixels, namely, an upper sub-pixel
and a lower sub-pixel. A contact hole 131 is formed between the
upper sub-pixel and the lower sub-pixel. Hereinafter, a generic
name for the first and second organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2 is simply referred to as a first
organic light emitting diode OLED1.
[0081] Each of the first to third organic light emitting diodes
OLED1 to OLED3 may be configured with a white light emitting diode.
In this case, it may be understood that the first to third organic
light emitting diodes include a blue color filter, a red color
filter, and a green color filter, respectively.
[0082] Therefore, each of the unit pixels 120 includes the first
sub-pixel 110a including the first organic light emitting diode
OLED1, the second sub-pixel 110b including the second organic light
emitting diode OLED2, and the third sub-pixel 110c including the
third organic light emitting diode OLED3.
[0083] First, in one of the unit pixels 120 formed in the organic
light emitting display panel, the first and second sub organic
light emitting diodes OLED1.sub.--1 and OLED1.sub.--2 included in
the first organic light emitting diode OLED1 configuring the first
sub-pixel 110a are separated from each other in a first direction
vertical to the horizontal line, and the second organic light
emitting diode OLED2 configuring the second sub-pixel 110b and the
third organic light emitting diode OLED3 configuring the third
sub-pixel 110c are disposed along the first direction. For example,
when a direction of a data line is designated as a vertical
direction (a first direction) and a direction of a gate line is
designated as a lateral direction (a second direction), the first
and second sub organic light emitting diodes OLED1.sub.--1 and
OLED1.sub.--2 are vertically separated from each other on a plane
view.
[0084] Here, the first direction denotes a direction vertical to
the horizontal line. The gate line may be formed along the
horizontal line in the organic light emitting display panel 100. In
this case, the first direction may be a direction vertical to the
gate line.
[0085] The first organic light emitting diode OLED1 configuring the
first sub-pixel 110a is divided into the first and second sub
organic light emitting diodes OLED1.sub.--1 and OLED1.sub.--2.
Since the first organic light emitting diode OLED1 is divided into
the first and second organic light emitting diodes OLED1.sub.--1
and OLED1.sub.--2, the first sub-pixel 110a may output more light.
Therefore, the first and second organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2 may be organic light emitting
diodes that express blue, but are not limited thereto. For example,
the first and second organic light emitting diodes OLED1.sub.--1
and OLED1.sub.--2 may be red organic light emitting diodes or green
organic light emitting diodes. Hereinafter, for convenience of
description, a case in which the first and second organic light
emitting diodes OLED1.sub.--1 and OLED1.sub.--2 configuring the
first organic light emitting diode OLED1 are blue organic light
emitting diodes will be described as an example of the present
invention.
[0086] To provide an additional description, each of the unit
pixels 120 configuring the organic light emitting display panel 100
includes the first organic light emitting diode OLED1, configured
with the first and second organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2 which are separated from each other
in the first direction, and the second and third organic light
emitting diodes OLED2 and OLED3 which are separated from each other
along the first direction.
[0087] Second, in each of the unit pixels 120, a contact hole 130
for electrically connecting an organic light emitting diode 113 to
a driving TFT 112 which drives the organic light emitting diode 113
formed in each of the unit pixels 120 is formed between the first
and second sub organic light emitting diodes OLED1.sub.--1 and
OLED1.sub.--2 and between the second and third organic light
emitting diodes OLED2 and OLED3.
[0088] For example, a first contact hole 131 which electrically
connects a first driving TFT (which drives the first and second sub
organic light emitting diodes OLED1.sub.--1 and OLED1.sub.--2) to
the first and second sub organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2, a second contact hole 132 which
electrically connects a second TFT (which drives the second organic
light emitting diode OLED2) to the second organic light emitting
diode OLED2, and a third contact hole 133 which electrically
connects a third TFT (which drives the third organic light emitting
diode OLED3) to the third organic light emitting diode OLED3 are
formed in one row along a contact hole part Y.
[0089] Here, the contact hole part Y is formed along a second
direction parallel to the horizontal line. For example, the contact
hole part Y is formed near a central line which vertically divides
the unit pixels 120 along the horizontal line.
[0090] To provide an additional description, the contact hole part
Y is formed along the second direction parallel to the horizontal
line, and particularly, is formed near the central line which
vertically divides the unit pixels 120 along the horizontal
line.
[0091] Third, the second organic light emitting diodes OLED2
respectively formed in the unit pixels 120 which are adjacent to
each other in the first direction are adjacent to each other, and
the third organic light emitting diodes OLED3 respectively formed
in the unit pixels 120 which are adjacent to each other in the
first direction are adjacent to each other.
[0092] For example, in a first unit pixel A1 which is formed at a
left upper end among four unit pixels 120 illustrated in FIG. 3,
the second and third organic light emitting diodes OLED2 and OLED3
are disposed in a vertical direction along the first direction, and
particularly, the third organic light emitting diode OLED3 is
disposed at a lower side. Also, in a second unit pixel A2 which is
formed at a left lower end among the four unit pixels 120
illustrated in FIG. 3, the second and third organic light emitting
diodes OLED2 and OLED3 are disposed in a vertical direction along
the first direction, and particularly, the third organic light
emitting diode OLED3 is disposed at an upper side.
[0093] Therefore, the third organic light emitting diodes OLED3
respectively formed in the first and second unit pixels A1 and A2
which are adjacent to each other in the first direction are
adjacent to each other.
[0094] Moreover, in a third unit pixel A3 which is formed at a
right upper end among the four unit pixels 120 illustrated in FIG.
3, the second and third organic light emitting diodes OLED2 and
OLED3 are disposed in a vertical direction along the first
direction, and particularly, the second organic light emitting
diode OLED2 is disposed at a lower side. Also, in a fourth unit
pixel A4 which is formed at a right lower end among the four unit
pixels 120 illustrated in FIG. 3, the second and third organic
light emitting diodes OLED2 and OLED3 are disposed in a vertical
direction along the first direction, and particularly, the second
organic light emitting diode OLED2 is disposed at an upper
side.
[0095] Therefore, the second organic light emitting diodes OLED2
respectively formed in the third and fourth unit pixels A3 and A4
which are adjacent to each other in the first direction are
adjacent to each other.
[0096] In addition, since the unit pixels 120 formed in the organic
light emitting display panel 100 are formed in a pattern
illustrated in FIG. 3, the second organic light emitting diodes
OLED2 respectively formed in the unit pixels 120 which are adjacent
to each other in the first direction are adjacent to each other,
and the third organic light emitting diodes OLED3 respectively
formed in the unit pixels 120 which are adjacent to each other in
the first direction are adjacent to each other.
[0097] Fourth, in each of unit pixels which are adjacent to each
other in the first direction, the second and third organic light
emitting diodes are formed at different positions.
[0098] For example, as described above, since the second organic
light emitting diodes OLED2 respectively formed in the unit pixels
120 which are adjacent to each other in the first direction are
adjacent to each other, and the third organic light emitting diodes
OLED3 respectively formed in the unit pixels 120 which are adjacent
to each other in the first direction are adjacent to each other,
the second and third organic light emitting diodes are formed at
different positions in each of unit pixels which are adjacent to
each other in the first direction.
[0099] Fifth, in each of unit pixels which are adjacent to each
other in the second direction parallel to the horizontal line, the
second and third organic light emitting diodes are formed at
different positions.
[0100] For example, in the first unit pixel A1 which is formed at
the left upper end among the four unit pixels 120 illustrated in
FIG. 3, the second and third organic light emitting diodes OLED2
and OLED3 are disposed in the vertical direction along the first
direction, and particularly, the third organic light emitting diode
OLED3 is disposed at the lower side. Also, in the third unit pixel
A3 which is formed at the right upper end among the four unit
pixels 120 illustrated in FIG. 3, the second and third organic
light emitting diodes OLED2 and OLED3 are disposed in the vertical
direction along the first direction, and particularly, the third
organic light emitting diode OLED3 is disposed at an upper
side.
[0101] Therefore, the second and third organic light emitting
diodes OLED2 and OLED3 respectively formed in the first and third
unit pixels A1 and A3 which are adjacent to each other in the
second direction are formed at different positions.
[0102] However, the second and third organic light emitting diodes
OLED2 and OLED3 respectively formed in the first and third unit
pixels A1 and A3 which are adjacent to each other in the second
direction may be formed at the same position. For example, the
third unit pixel A3 which is formed at the right upper end among
the four unit pixels 120 illustrated in FIG. 3 may be formed in the
same type as that of the first unit pixel A1 which is formed at the
left upper end among the four unit pixels 120 illustrated in FIG.
3.
[0103] Sixth, the contact hole part Y may be formed to be covered
by a bank. This will be described in detail with reference to FIG.
6.
[0104] Seventh, a first electrode or second electrode of the
organic light emitting diode 113 is electrically connected to the
driving TFT 112 through the contact hole 130.
[0105] For example, the first electrode or the second electrode may
be the anode electrode or the cathode electrode, and is
electrically connected to the driving TFT 112 through the contact
hole 130.
[0106] FIG. 6 is an exemplary diagram illustrating a
cross-sectional surface taken along line X-X' of the organic light
emitting display panel of FIG. 5.
[0107] The organic light emitting display panel 100 according to
the embodiments of the present invention, as illustrated in FIG. 6,
includes a sub-pixel 110 based on a top emission type. Since FIG. 6
illustrates a cross-sectional surface taken along line X-X' of the
organic light emitting display panel of FIG. 5, a second bank part
119b, a first sub organic light emitting diode OLED1.sub.--1, a
first bank part 119a, a second sub organic light emitting diode
OLED1.sub.--2, a second bank part 119b, a first sub organic light
emitting diode OLED1.sub.--1, and a first bank part 119a are formed
in this order from a left side in the organic light emitting
display panel illustrated in FIG. 6.
[0108] First, the second bank part 119b divides the unit pixels 120
in the first direction. Therefore, a bank 117 is formed in the
second bank part 119b.
[0109] Second, as described above, the first sub organic light
emitting diode OLED1.sub.--1 is an organic light emitting diode
configuring the first sub-pixel.
[0110] Third, the contact hole 130 and the bank 117 covering the
contact hole 130 are formed in the first bank part 119a. In this
case, the connection line 111 is formed in the contact hole 130,
and a first electrode (an anode) of the first sub organic light
emitting diode OLED1.sub.--1 is connected to a first electrode (an
anode) of the second sub organic light emitting diode OLED1.sub.--2
through the connection line 111.
[0111] The driving TFT 112 may be formed at a lower end of the
first bank part 119 with a planarizing layer 115 therebetween.
[0112] Fourth, the second sub organic light emitting diode
OLED1.sub.--2 is an organic light emitting diode configuring the
first sub-pixel.
[0113] The first and second sub organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2 configure the first organic light
emitting diode OLED1 configuring the first sub-pixel.
[0114] Since the first and second sub organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2 are electrically connected to the
driving TFT 112 through the connection line 111, the first and
second sub organic light emitting diodes OLED1.sub.--1 and
OLED1.sub.--2 are simultaneously driven by the driving TFT 112.
[0115] The first and second sub organic light emitting diodes
OLED1.sub.--1 and OLED1.sub.--2 each include a first electrode used
as an anode electrode, a second electrode used as a cathode
electrode, and an emission layer 114 formed between the first and
second electrodes.
[0116] A protective layer 116 may be stacked on the second
electrode (a cathode), and a color filter (not shown in FIG. 6) may
be formed on the protective layer 116. However, the color filter
may not be provided, or may be formed at another position.
[0117] Fifth, as described above, the second bank part 119b divides
the unit pixels 120 in the first direction. In FIG. 4, the second
bank part 119b formed between the first and second sub organic
light emitting diodes OLED1.sub.--1 and OLED1.sub.--2, and divides
the first and second unit pixels illustrated in FIG. 3.
[0118] Sixth, the first sub organic light emitting diode
OLED1.sub.--1 formed at a right side of FIG. 6 performs the same
function as that of the above-described first sub organic light
emitting diode OLED1.sub.--1, and the first bank 119a formed at the
right side of FIG. 6 performs the same function as that of the
above-described first bank 119a.
[0119] FIG. 7 is an exemplary diagram illustrating an interval
between the organic light emitting diodes in the organic light
emitting display panel of FIG. 5. In FIG. 7, a unit of a numerical
value may be .mu.m.
[0120] In the organic light emitting display panel according to the
third embodiment of the present invention, as illustrated in FIG.
7, organic light emitting diodes of the same color may be formed in
adjacent areas in unit pixels which are adjacent to each other in
the first direction.
[0121] Therefore, in pixels which are adjacent to each other in the
first direction, an interval between two adjacent organic light
emitting diodes may be, for example, 10 .mu.m. In the related art,
in pixels which are adjacent to each other in the first direction,
an interval between two adjacent organic light emitting diodes may
be about 30 .mu.m. However, according to the present embodiment,
the interval is reduced by 20 .mu.m. Therefore, according to the
present embodiment, an opening is further widened.
[0122] The above-described organic light emitting display panel
according to the third embodiment of the present invention will be
briefly described below.
[0123] In an organic light emitting display panel where colors are
alternated in units of two colors and which is formed in a pixel
structure where a contact hole is formed at a lower end of a pixel,
two sub-pixels may be formed by using one slot hole, and thus, a
distance between slots is reduced, thereby increasing an area of an
opening. That is, considering the same aperture ratio, a high
resolution is realized. However, considering both the structure and
a driving TFT, a contact hole is formed between the same colors
facing each other, and thus, an increase effect of an opening is
reduced.
[0124] Therefore, a method in which a position of the contact hole
130 is differently provided was proposed for maximizing an increase
effect of an area of an opening of a fine metal mask. In this case,
however, in designing the driving TFT, positions of a line and the
driving TFT deviate from the original positions, and thus, an
additional area necessary for designing is needed, whereby
implementation of a high resolution is limited.
[0125] According to the third embodiment of the present invention,
the organic light emitting display panel has a color alternation
structure and a structure for maximizing an increase effect of an
area of an opening, and as illustrated in FIG. 5, the contact hole
130 is disposed between different colors. Also, according to the
present embodiment, in a case of a color (generally, blue) using a
slit mask, one organic light emitting diode (the first organic
light emitting diode OLED1 in FIG. 3) is separated into two sub
organic light emitting diodes by the bank in order for the contact
hole 130 to be disposed on the same line.
[0126] That is, in the present embodiment, the contact hole 130 is
disposed in a pixel using the slit mask, and the bank is formed at
a position of the contact hole 130. Therefore, non-planarization of
the contact hole 130 can be prevented, and thus, a deposition
failure of the organic light emitting display panel can be
prevented.
[0127] To provide an additional description, in the present
embodiment, an emission part is formed by dividing a sub-pixel
using the slit mask into two segments, thereby realizing a high
resolution.
[0128] Further, in the present embodiment, a structure in which the
same colors face each other is used, thereby securing an
opening.
[0129] Furthermore, in the present embodiment, since the contact
hole connected to the driving TFT is disposed at the same position,
a high-resolution organic light emitting display panel is
designed.
[0130] Moreover, in the present embodiment, since the bank is
formed on the contact hole, a deposition failure of the organic
light emitting display panel caused by a high step height can be
prevented.
[0131] In the organic light emitting display panel according to the
embodiments of the present invention, a plurality of unit pixels
that each include first to third sub-pixels respectively including
OLEDs of different colors are arranged in a matrix type.
[0132] In the present invention where a plurality of unit pixels
are arranged in a matrix type, sub-pixels having the same color
among a plurality of sub-pixels configuring a unit pixel may be
arranged adjacent to each other, thereby enhancing a sense of
color.
[0133] Further, according to the embodiments of the present
invention, since first to third sub-pixels configuring a unit pixel
are respectively disposed adjacent to first to third sub-pixels
adjacent thereto, a width of an emission area can increase.
[0134] Moreover, according to the embodiments of the present
invention, a non-deposition of an OLED and a non-emission of a
pixel which are caused by a non-planarization of a contact hole in
a bank open area can be prevented.
[0135] Particularly, in one unit pixel applied to the organic light
emitting display panel according to the third embodiment of the
present invention, the first OLEDs configuring the first sub-pixel
are vertically separated from each other and are respectively
included in the upper sub-pixel and the lower sub-pixel, and the
second OLED configuring the second sub-pixel and the third OLED
configuring the third sub-pixel are disposed upward and downward.
Therefore, according to the third embodiment of the present
invention, sub-pixels included in adjacent unit pixels are arranged
adjacent to a boundary between adjacent unit pixels, thereby
enhancing an aperture ratio of each unit pixel. Also, in designing
the fine metal mask used to form a sub-pixel of a unit pixel, the
rib of the fine metal mask may be thinly designed, and thus, the
present invention contributes to manufacture a high-resolution
organic light emitting display panel.
[0136] In addition, in the embodiments of the present invention,
the contact holes may be arranged in one row in a certain
direction, and thus, it is easy to manufacture the fine metal mask.
Also, second and third sub-pixels configuring a unit pixel may be
respectively disposed adjacent to second and third sub-pixels
configuring an adjacent unit pixel, and thus, it is possible to
manufacture the fine metal mask for enhancing an aperture ratio. In
particular, in manufacturing a high-resolution organic light
emitting display panel, the manufacturing of the fine metal mask is
limited, but the present invention overcomes the limitation, and
enables a finer sub-pixel to be manufactured. Also, in the present
invention, sub-pixels are arranged in parallel in a unit pixel, and
thus, it is easy to manufacture the fine metal mask.
[0137] It will be apparent to those skilled in the art that various
modifications and variations can be made in the present invention
without departing from the spirit or scope of the inventions. Thus,
it is intended that the present invention covers the modifications
and variations of this invention provided they come within the
scope of the appended claims and their equivalents.
* * * * *