U.S. patent application number 14/283133 was filed with the patent office on 2015-06-25 for touch display panel with electrostatic protection unit.
This patent application is currently assigned to Shanghai Tianma Micro-Electonics Co., Ltd.. The applicant listed for this patent is Shanghai Tianma Micro-Electonics Co., Ltd., Tianma Micro-Electronics Co., Ltd.. Invention is credited to Huiping Chai, Zhongshou Huang, Qijun Yao, Xingyao ZHOU.
Application Number | 20150177859 14/283133 |
Document ID | / |
Family ID | 51189597 |
Filed Date | 2015-06-25 |
United States Patent
Application |
20150177859 |
Kind Code |
A1 |
ZHOU; Xingyao ; et
al. |
June 25, 2015 |
TOUCH DISPLAY PANEL WITH ELECTROSTATIC PROTECTION UNIT
Abstract
A touch display panel and a display device with the same
includes driving electrodes, sensing electrodes insulated from each
other, driving electrode leads, sensing electrode leads, first
external terminals and second external terminals, all disposed on
the color filter substrate. The driving electrodes are respectively
connected with the first external terminals by the driving
electrode leads, the sensing electrodes are respectively connected
with the second external terminals by the sensing electrode leads;
third external terminals on a TFT array substrate respectively
correspond to and are electrically connected with the first
external terminals, fourth external terminals on the TFT array
substrate respectively correspond to and are electrically connected
with the second external terminals; the third external terminals
and the fourth external terminals are connected with a common
electrode line through an electrostatic protection unit, thereby
protecting the driving electrodes and the sensing electrodes
against electrostatic discharge.
Inventors: |
ZHOU; Xingyao; (Shanghai,
CN) ; Yao; Qijun; (Shanghai, CN) ; Chai;
Huiping; (Shanghai, CN) ; Huang; Zhongshou;
(Shanghai, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Shanghai Tianma Micro-Electonics Co., Ltd.
Tianma Micro-Electronics Co., Ltd. |
Shanghai
Shenzhen |
|
CN
CN |
|
|
Assignee: |
Shanghai Tianma Micro-Electonics
Co., Ltd.
Shanghai
CN
Tianma Micro-Electronics Co., Ltd.
Shenzhen
CN
|
Family ID: |
51189597 |
Appl. No.: |
14/283133 |
Filed: |
May 20, 2014 |
Current U.S.
Class: |
349/12 |
Current CPC
Class: |
G06F 3/0412 20130101;
G02F 1/136204 20130101; G02F 1/13338 20130101; G06F 3/041
20130101 |
International
Class: |
G06F 3/041 20060101
G06F003/041 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 23, 2013 |
CN |
201310718974.9 |
Claims
1. A touch display panel, comprising: a color filter substrate; a
TFT array substrate disposed opposite to the color filter
substrate; a plurality of driving electrodes and a plurality of
sensing electrodes disposed on the color filter substrate and being
electrically insulated from each other; a plurality of driving
electrode leads, a plurality of sensing electrode leads, a
plurality of first external terminals, and a plurality of second
external terminals disposed on the color filter substrate, wherein
each of the driving electrodes is connected with one of the first
external terminals by a corresponding driving electrode lead, and
each of the sensing electrodes is connected with one of the second
external terminals by a corresponding sensing electrode lead; a
plurality of third external terminals and a plurality of fourth
external terminals disposed on the TFT array substrate, wherein
each of the third external terminals is electrically connected with
one of the first external terminals, and each of the fourth
external terminals is electrically connected with one of the second
external terminals; a common electrode line disposed on the TFT
array substrate; and an electrostatic protection unit disposed on
the TFT array substrate and configured to connect the third
external terminals and the fourth external terminals with the
common electrode line.
2. The touch display panel of claim 1, wherein the plurality of
driving electrodes and the plurality of sensing electrodes are
located on a first conductive layer.
3. The touch display panel of claim 1, wherein, the plurality of
driving electrodes are located on a first conductive layer, the
plurality of sensing electrodes are located on a second conductive
layer, and an insulating layer is disposed between the first
conductive layer and the second conductive layer.
4. The touch display panel of claim 1, wherein the electrostatic
protection unit comprises an array of n rows and m columns of TFTs,
each row comprising m pairs of TFTs connected in series for a total
of n.times.2m TFTs, n and m being positive integers, each pair of
TFTs comprising a first TFT and a second TFT connected in parallel
with each other and having an input end and an output end, wherein
a gate electrode of the first TFT, a drain electrode of the first
TFT and a source electrode of the second TFT are connected together
at the input end, and a gate electrode of the second TFT, a drain
electrode of the second TFT and a source electrode of the first TFT
are connected together at the output end; the input end of each
pair of TFTs except the first pair of TFTs in a row is connected
with an output end of a preceding pair of TFTs, an input end of the
first pair of TFTs is an input end of the row, and the output end
of the m-th pair of TFTs in the row is an output end of the row;
input ends of the n rows of TFTs are connected together at an input
end of the electrostatic protection unit, and output ends of the n
rows of TFTs are connected together at an output end of the
electrostatic protection unit; and the input end of the
electrostatic protection unit is connected to the third external
terminals and the fourth external terminals, and the output end of
the electrostatic protection unit is connected to the common
electrode line.
5. The touch display panel of claim 4, wherein the electrostatic
protection unit comprises a pair of TFTs comprising a first TFT and
a second TFT, a gate electrode of the first TFT, a drain electrode
of the first TFT and a source electrode of the second TFT being
connected together at the input end of the electrostatic protection
unit, and a gate electrode of the second TFT, a drain electrode of
the second TFT and a source electrode of the first TFT being
connected together at the output end of the electrostatic
protection unit.
6. The touch display panel of claim 4, wherein the electrostatic
protection unit comprises two pairs of TFTs connected in parallel
and having each an input end and an output end, and each of the two
pairs of TFTs comprises a first TFT and a second TFT, wherein a
gate electrode of the first TFT, a drain electrode of the first TFT
and a source electrode of the second TFT are connected together at
the input end of the pair of TFTs, and a gate electrode of the
second TFT, a drain electrode of the second TFT and a source
electrode of the first TFT are connected together at the output end
of the pair of TFTs; the input ends of the two pairs of TFTs are
connected together at the input end of the electrostatic protection
unit, and the output ends of the two pairs of TFTs are connected
together at the output end of the electrostatic protection
unit.
7. The touch display panel of claim 4, wherein the electrostatic
protection unit comprises two pairs of TFTs connected in series,
and each of the two pairs of TFTs comprises a first TFT and a
second TFT; a gate electrode of the first TFT, a drain electrode of
the first TFT and a source electrode of the second TFT are
connected together at an input end of the pair of TFTs, and a gate
electrode of the second TFT, a drain electrode of the second TFT
and a source electrode of the first TFT are connected together at
an output end of the pair of TFTs; the input end of the first pair
of TFTs is the input end of the electrostatic protection unit, the
output end of the first pair of TFTs is connected to the input end
of the second pair of TFTs, and the output end of the second pair
of TFTs is the output end of the electrostatic protection unit.
8. The touch display panel of claim 1, wherein the electrostatic
protection unit comprises an array of n rows and m columns of TFTs,
each row comprising m TFTs connected in series, for a total of
n.times.m TFTs, n being an odd number greater than 1 and m being a
positive integer; a gate electrode and a drain electrode of each
TFT are connected at an input end of the TFT, and a source
electrode of each TFT is an output end of the TFT; an input end of
each TFT except the first TFT in a row is connected with an output
end of a preceding TFT, an input end of the first TFT is an input
end of the row, and an output end of an m-th TFT is an output end
of the row; input ends of any (n+1)/2 rows of TFTs and output ends
of remaining (n-1)/2 rows of TFTs are connected together at the
input end of the electrostatic protection unit, and output ends of
the (n+1)/2 rows of TFTs and input ends of said remaining (n-1)/2
rows of TFTs are connected together at the output end of the
electrostatic protection unit; and the input end of the
electrostatic protection unit is connected to the third external
terminals and the fourth external terminals, and the output end of
the electrostatic protection unit is connected to the common
electrode line.
9. The touch display panel of claim 8, wherein the electrostatic
protection unit comprises three rows of TFTs connected in parallel,
each row comprising two TFTs connected in series; a gate electrode
and a drain electrode of each TFT are connected together at an
input end of the TFT, and a source electrode of the TFT is an
output end of the TFT; in each of the three rows of TFTs, an input
end of the first TFT is an input end of the row of TFTs, an output
end of the first TFT is connected with an input end of the second
TFT, and an output end of the second TFT is an output end of the
row of TFTs; input ends of any two rows of TFTs and output end of
the remaining one row of TFTs are connected together at the input
end of the electrostatic protection unit, and output ends of said
two rows of TFTs and the input end of said remaining one row of
TFTs are connected together at the output end of the electrostatic
protection unit.
10. The touch display panel of claim 1, wherein the electrostatic
protection unit comprises n rows of TFTs connected in parallel with
each other, each row comprising m TFTs connected in series, n being
an odd number greater than 1 and m being a positive integer; a gate
electrode and a drain electrode of each TFT are connected at an
input end of the TFT, and a source electrode of each TFT is an
output end of the TFT; in each of the n rows of TFTs, an input end
of each TFT except the first TFT in the row is connected with an
output end of a preceding TFT, an input end of the first TFT is an
input end of the row of TFTs, and an output end of an m-th TFT is
an output end of the row of TFTs; input ends of any (n-1)/2 rows of
TFTs and output ends of remaining (n+1)12 rows of TFTs are
connected together at an input end of the electrostatic protection
unit, and output ends of the (n-1)/2 rows of TFTs and input ends of
said remaining (n+1)/2 rows of TFTs are connected together at an
output end of the electrostatic protection unit; and the input end
of the electrostatic protection unit is connected to the third
external terminals and the fourth external terminals, and the
output end of the electrostatic protection unit is connected to the
common electrode line.
11. The touch display panel of claim 10, wherein the electrostatic
protection unit comprises three rows of TFTs connected in parallel,
each row comprising two TFTs connected in series; a gate electrode
and a drain electrode of each TFT are connected together at an
input end of the TFT, and a source electrode of the TFT is an
output end of the TFT; in each of the three rows of TFTs, an input
end of the first TFT is an input end of the row of TFTs, an output
end of the first TFT is connected with an input end of the second
TFT, and an output end of the second TFT is an output end of the
row of TFTs; an input end of any row of TFTs and output ends of
remaining two rows of TFTs are connected together at the input end
of the electrostatic protection unit, and an output end of said any
row of TFTs and input ends of said remaining rows of TFTs are
connected together at the output end of the electrostatic
protection unit.
12. The touch display panel of claim 4, wherein, the TFT array
substrate further comprises an array of TFTs, which has a same main
structure with the TFTs of the electrostatic protection unit.
13. The touch display panel of claim 1, wherein the first external
terminals are electrically connected with the third external
terminals by Anisotropic Conductive Films, and the second external
terminals are electrically connected with the fourth external
terminals by Anisotropic Conductive Films.
14. A display device comprising the touch display panel of claim
1.
15. The touch display panel of claim 8, wherein the TFT array
substrate further comprises an array of TFTs, which has a same main
structure with the TFTs of the electrostatic protection unit.
16. The touch display panel of claim 10, wherein the TFT array
substrate further comprises an array of TFTs, which has a same main
structure with the TFTs of the electrostatic protection unit.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority to Chinese
Patent Application No. 201310718974.9, filed with the Chinese
Patent Office on Dec. 23, 2013 and entitled "TOUCH DISPLAY PANEL
AND DISPLAY DEVICE WITH THE SAME", the content of which is
incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relates to the field of display
technologies, in particular to a touch display panel and a display
device with the same.
BACKGROUND OF THE INVENTION
[0003] An Electrostatic Discharge (ESD) event is a high energy
pulse that can break through a semiconductor device or generate
sufficient heat to melt the semiconductor device. In the case of
damage caused by imperceptible degradation or malfunction of parts
of components of the semiconductor device, there will be
substantial economic losses. Therefore, an ESD event will cause
fatal damage to electronic products; it not only degrades the
reliability of the electronic products, but also increases
maintenance costs. Annual damages due to electrostatic discharge
are estimated to cause a loss of billions of dollars to the
electronics manufacturing industry.
BRIEF SUMMARY OF THE INVENTION
[0004] Embodiments of the present invention provide a touch display
panel and a display device with the same to solve technical
problems in the prior art that the product yield is reduced and
driving electrodes and sensing electrodes are damaged due to the
electrostatic discharge.
[0005] In a first aspect, the embodiment of the present invention
provides a touch display panel which includes:
[0006] a color filter substrate;
[0007] a TFT array substrate disposed opposite to the color filter
substrate;
[0008] a plurality of driving electrodes, and a plurality of
sensing electrodes electrically insulated from the driving
electrodes, wherein the plurality of driving electrodes and the
plurality of sensing electrodes are disposed on the color filter
substrate;
[0009] a plurality of driving electrode leads, a plurality of
sensing electrode leads, a plurality of first external terminals
and a plurality of second external terminals, all disposed on the
color filter substrate, where the driving electrodes are
respectively connected with the first external terminals by the
driving electrode leads, and the sensing electrodes are
respectively connected with the second external terminals by the
sensing electrode leads;
[0010] a plurality of third external terminals and a plurality of
fourth external terminals, both disposed on the TFT array
substrate, where the third external terminals respectively
correspond to and are electrically connected with the first
external terminals, and the fourth external terminals respectively
correspond to and are electrically connected with the second
external terminals;
[0011] a common electrode line disposed on the TFT array substrate;
and
[0012] an electrostatic protection unit disposed on the TFT array
substrate, with the third external terminals and the fourth
external terminals being connected with the common electrode line
through the electrostatic protection unit.
[0013] In a second aspect, an embodiment of the present invention
also provides a display device with a touch display panel, and the
touch display panel is one as provided in the first aspect as
above.
[0014] In the touch display panel and the display device with the
same as provided by the embodiments of the present invention, the
active electrostatic protection unit is provided on the TFT array
substrate, the input end of the electrostatic protection unit is
connected with the driving electrodes and the sensing electrodes
arranged on the color filter substrate, and the output end of the
electrostatic protection unit is connected with the common
electrode line arranged on the TFT array substrate, to protect the
driving electrodes and the sensing electrodes against the ESD,
thereby improving the yield of the display device with a touch
display panel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Other features, objects and advantages of the present
invention will become more apparent from the detailed description
for non-limiting embodiments made with reference to the accompany
drawings, in which:
[0016] FIG. 1A is a schematic diagram of a structure of a touch
display panel according to an embodiment of the present
invention;
[0017] FIG. 1B is a schematic diagram of a structure of the touch
display panel according to another embodiment of the present
invention;
[0018] FIG. 2A is a first circuit diagram of an electrostatic
protection unit of the touch display panel according to an
embodiment of the present invention;
[0019] FIG. 2B is a circuit diagram of a pair of TFTs of the
electrostatic protection unit in FIG. 2A;
[0020] FIG. 3 is a circuit diagram of a first specific
implementation of the electrostatic protection unit in FIG. 2A;
[0021] FIG. 4 is a circuit diagram of a second specific
implementation of the electrostatic protection unit in FIG. 2A;
[0022] FIG. 5 is a circuit diagram of a third specific
implementation of the electrostatic protection unit in FIG. 2A;
[0023] FIG. 6A is a second circuit diagram of the electrostatic
protection unit of the touch display panel according to an
embodiment of the present invention;
[0024] FIG. 6B is a circuit diagram of one of the TFTs of the
electrostatic protection unit in FIG. 6A;
[0025] FIG. 7 is a circuit diagram of a specific implementation of
the electrostatic protection unit in FIG. 6A;
[0026] FIG. 8 is a third circuit diagram of the electrostatic
protection unit of the touch display panel according to an
embodiment of the present invention;
[0027] FIG. 9 is a circuit diagram of a specific implementation of
the electrostatic protection unit in FIG. 8;
[0028] FIG. 10 is a schematic diagram of the TFTs in the
electrostatic protection unit according to an embodiment of the
present invention; and
[0029] FIG. 11 is a schematic view of the structure of a display
device with a touch display panel according to an embodiment of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The present invention will be further described in detail
below in conjunction with the accompanying drawings and
embodiments. It should be noted that the specific embodiments of
the present invention disclosed herein are illustrative and not
restrictive. It also is to be understood that the accompanying
drawings shows only parts relating to the present invention, but
not in an exhausting way, for the ease of description.
[0031] With the existing In-Cell Touch Panel (In-Cell TP)
technology, driving electrodes and sensing electrodes serving for a
touch function are integrated on the side of a color filter
substrate using a design of a touch pattern to form a touch panel.
In an actual manufactured touch panel, the driving electrodes and
the sensing electrodes can be disposed in the same conductive layer
or two different conductive layers of the color filter substrate.
However, a conductive layer provided for the touch functionality is
susceptible to electrostatic discharge or can even be damaged by an
electrostatic discharge event. Thus, such conductive layer
adversely affects the color filter substrate compared with a color
filter substrate without touch functionality. Unlike a Thin Film
Transistor (TFT) array substrate, it is not possible to provide an
active device for protecting the driving electrodes or the sensing
electrodes against electrostatic discharge in the case of the color
filter substrate, due to the structural characteristics of the
color filter substrate. Thus, during the actual production of a
display device with a touch display panel, in stages where static
electricity is likely generated, such as a stage of forming an
oriented film and a stage of injecting liquid crystals,
electrostatic discharge would very likely occur between the driving
electrodes and the sensing electrodes and hence cause a short
circuit of the driving electrodes or the sensing electrodes or
damage the driving electrodes or the sensing electrodes, thereby
reducing the yield of the display device with a touch display
panel.
[0032] FIG. 1A is a schematic diagram of a structure of a touch
display panel according to an embodiment of the present invention.
As shown in FIG. 1A, the touch display panel includes: a color
filter substrate 11; a TFT array substrate 12 disposed opposite to
the color filter substrate 11; a plurality of driving electrodes
111, and a plurality of sensing electrodes 112 electrically
insulated from the driving electrodes 111 and located in the same
layer with the driving electrodes 111, with both the plurality of
driving electrodes 111 and the plurality of sensing electrodes 112
being disposed on the color filter substrate 11; a plurality of
driving electrode leads 113, a plurality of sensing electrode leads
114. The touch display panel also includes a plurality of first
external terminals 115 and a plurality of second external terminals
116, all disposed on the color filter substrate, where the driving
electrodes 111 are respectively connected with the first external
terminals 115 by the driving electrode leads 113, and the sensing
electrodes 112 are respectively connected with the second external
terminals 116 by the sensing electrode leads 114; a plurality of
third external terminals 121 and a plurality of fourth external
terminals 122, both disposed on the TFT array substrate 12, where
the third external terminals 121 respectively correspond to and are
electrically connected with the first external terminals 115 (as
indicated by the broken lines between the first external terminals
115 and the third external terminals 121 in FIG. 1a), and the
fourth external terminals 122 respectively correspond to and are
electrically connected with the second external terminals 116 (as
indicated by the broken lines between the second external terminals
116 and the fourth external terminals 122 in FIG. 1A). The touch
display panel further includes a common electrode line 123 disposed
on the TFT array substrate 12; and an electrostatic protection unit
13 disposed on the TFT array substrate 12, with the third external
terminals 121 and the fourth external terminals 122 being connected
with the common electrode line 123 through the electrostatic
protection unit 13, here, the connection between the electrostatic
protection unit 13 and the common electrode line 123 is not shown
in FIG. 1A.
[0033] FIG. 1B is a schematic diagram of a structure of a touch
display panel according to another embodiment of the present
invention. The structure shown in FIG. 1B is different from that of
FIG. 1A in that the plurality of driving electrodes 111 are located
on a first conductive layer 101, the plurality of sensing
electrodes 112 are located on a second conductive layer 102, where
the first conductive layer 101 and the second conductive layer 102
are both located on the color filter substrate (not shown in FIG.
1B), and an insulating layer (not shown in FIG. 1B) is disposed
between the first conductive layer 101 and the second conductive
layer 102. Correspondingly, the plurality of driving electrodes
leads 113 and the plurality of first external terminals 115 are
both located on the first conductive layer 101, and the plurality
of sensing electrodes 114 and the plurality of second external lead
terminals 116 are both located on the second conductive layer 102,
where the driving electrodes 111 are respectively connected with
the first external terminals 115 by the driving electrode leads
113, and the sensing electrodes 112 are respectively connected with
the second external terminals 116 via the sensing electrode leads
114. The first external terminals 115 and the second external
terminals 116 are respectively connected with corresponding
external terminals on the TFT array substrate 12 to be connected to
the electrostatic protection unit 13, similar to the description
provided with reference to FIG. 1A, and thus will not be repeated
herein for the sake of brevity.
[0034] It should be noted that, since a color resistance layer is
electrically insulating and typically disposed between a first
conductive layer and a second conductive layer, the insulating
layer disposed between the first conductive layer 101 and the
second conductive layer 102 may be a color resistance layer.
[0035] Further, the common electrode line 123 may be made of a
transparent conductive material such as indium zinc oxide, indium
tin oxide, or a combination thereof. Such common electrode line may
extend across the whole TFT array substrate, and thus has a large
surface area to facilitate the connection with the electrostatic
protection unit. Further, in the case of the same amount of
charges, a larger surface area of the common electrode line means a
lower surface charge density on the surface of the common electrode
line, thus, the common electrode line obtains a strong charge
endurance of. In addition, the potential of the common electrode
line is low, which is advantageous for the release of electrostatic
charges by the electrostatic protection unit.
[0036] In a specific example embodiment of the present invention,
the first external terminals 115 are electrically connected with
the third external terminals 121 by Anisotropic Conductive Films
(ACFs), and likewise the second external terminals 116 are
electrically connected with the fourth external terminals 122 by
ACFs. The ACF has a good electrical conductivity and has a
capability of anisotropic electrical conduction, and thus allows
the first external terminal 115 and the second external terminal
116 to be respectively electrically connected with the third
external terminal 121 and the fourth external terminal 122 in a
direction perpendicular to the color filter substrate 11 and the
TFT array substrate 12, and insulated from each other in a
direction parallel to the color filter substrate 11 and the TFT
array substrate 12.
[0037] FIG. 2A is a first circuit diagram of the electrostatic
protection unit of the touch display panel according to an
embodiment of the present invention. FIG. 2B is a circuit diagram
of a pair of TFTs of the electrostatic protection unit in FIG. 2A.
In one specific example embodiment of the present invention,
referring to FIG. 2A, the electrostatic protection unit includes an
array of n rows and m columns of TFTs, with each row including m
pairs of TFTs connected in parallel with each other. Thus, the
electrostatic protection unit includes a total of n.times.2m TFTs,
where n and m are positive integers.
[0038] Referring to FIG. 2B, each of the pairs of TFTs includes a
first TFT 21 and a second TFT 22, where a gate electrode 211 of the
first TFT 21, a drain electrode 212 of the first TFT 21 and a
source electrode 223 of the second TFT 22 are connected together at
a joint which functions as an input end IP1 of this pair of TFTs,
while a gate electrode 221 of the second TFT 22, a drain electrode
222 of the second TFT 22 and a source electrode 213 of the first
TFT 21 are connected together at a joint which functions as an
output end OP1 of this pair of TFTs.
[0039] Referring to FIG. 2A, in each of the n rows of TFTs, the
input end IP1 of each pair of TFTs except for the first pair of
TFTs in this row is connected with the output end OP1 of the
preceding pair of TFTs, the input end IP1 of the first pair of TFTs
functions as an input end IP2 of this row of TFTs, and the output
end OP1 of the m-th pair of TFTs in this row functions as an output
end OP2 of this row of TFTs.
[0040] For example, referring to FIG. 2A, in each of the n rows of
TFTs, the input end IP1 of the first pair of TFTs functions as an
input end IP2 of this row of TFTs, the input end IP1 of the i-th
subsequent pair of TFTs is connected with the output end OP1 of the
preceding (i-1)-th pair of TFTs, and the output end OP1 of the m-th
pair of TFTs in this row functions as an output end OP2 of this row
of TFTs, where i denotes any positive integer larger than 1 and
less than or equal to m.
[0041] All the input ends IP2 of the TFTs in the above n rows are
connected together at a joint which functions as an input end IP3
of the electrostatic protection unit, and all the output ends OP2
of the TFTs in the above n rows are connected together at a joint
which functions as an output end OP3 of the electrostatic
protection unit.
[0042] The input end IP3 of the electrostatic protection unit is
connected to the third external terminals 121 and the fourth
external terminals 122, and the output end OP3 of the electrostatic
protection unit is connected to the common electrode line 123.
[0043] As such, since each of the above n rows of TFTs includes m
pairs of TFTs, if positive electrostatic charges are present at the
input end IP3 of the electrostatic protection unit, only when an
electrostatic voltage applied between the input end IP3 and the
output end OP3 of the electrostatic protection unit reaches m times
of a turning-on threshold voltage of the TFT, m forwardly connected
TFTs in each of the above n rows (hereinafter, the m forwardly
connected TFTs in each row are such that, the gate electrode and
the drain electrode of each of the m forwardly connected TFTs
except for the first one of the m forwardly connected TFTs are
connected to the source electrode of the preceding TFT, the gate
and drain electrodes of the first TFT are connected to the input
end of the electrostatic protection unit, and the source electrode
of the m-th TFT is connected to the output end of the electrostatic
protection unit) are all turned on, so that a conductive path for
releasing the positive electrostatic charges is formed between the
input end IP3 and the output end OP3 of the electrostatic
protection unit, thus achieving an effect of electrostatic
protection. Similarly, if negative electrostatic charges are
present at the input end IP3 of the electrostatic protection unit,
only when an electrostatic voltage applied between the input end
IP3 and the output end OP3 of the electrostatic protection unit
reaches m times of a turning-on threshold voltage of the TFT, m
reversely connected TFTs in each of the above n rows (hereinafter,
the m reversely connected TFTs in each row are such that, the
source electrode of each of m reversely connected TFTs except for
the first one of the m reversely connected TFTs is connected to the
gate and drain electrodes of the preceding TFT, the source
electrode of the first TFT is connected to the input end of the
electrostatic protection unit, and the gate and drain electrodes of
the m-th TFT are connected to the output end of the electrostatic
protection unit) are all turned on, so that the conductive path for
releasing the negative electrostatic charges is formed between the
input end IP3 and the output end OP3 of the electrostatic
protection unit, thus protecting the driving electrodes and the
sensing electrodes against electrostatic discharge. As such, the
electrostatic protection unit is at its conductive state only if
the applied electrostatic voltage is m times of the turning-on
threshold voltage of the TFT, and hence can endure a high
electrostatic voltage. In addition, once the electrostatic
protection unit is at its conductive state, the formed conductive
path includes n parallel rows of TFTs (with each row of TFTs
containing m TFTs that are turned on), thus the electrostatic
protection unit at its conductive state can endure a high
conductive current because of the current division by the parallel
circuits.
[0044] Further, several specific implementations of the
electrostatic protection unit in FIG. 2A are given below in
conjunction with FIGS. 3 to 5. FIG. 3 is a circuit diagram of a
first specific implementation of the electrostatic protection unit
in FIG. 2A. Referring to FIG. 3, the electrostatic protection unit
includes a pair of TFTs including a first TFT 21 and a second TFT
22, a gate electrode 211 of the first TFT 21, a drain electrode 212
of the first TFT 21 and a source electrode 223 of the second TFT 22
are connected together at a joint which functions as the input end
IP3 of the electrostatic protection unit, and a gate electrode 221
of the second TFT 22, a drain electrode 222 of the second TFT 22
and a source electrode 213 of the first TFT 21 are connected
together at a joint which functions as the output end OP3 of the
electrostatic protection unit. The input end IP3 of the
electrostatic protection unit is connected to the third external
terminals 121 and the fourth external terminals 122, and the output
end OP3 of the electrostatic protection unit is connected to the
common electrode line 123.
[0045] The electrostatic protection unit shown in FIG. 3 is a
simple structure formed by a pair of TFTs (a basic unit) of the
electrostatic protection unit shown in FIG. 2A. Because the
generated electrostatic charges may be positive or negative,
forwardly connected TFTs are required for releasing the positive
electrostatic charges, and reversely connected TFTs are required
for releasing the negative electrostatic charges, a structure
having a function of electrostatic protection at least includes one
forwardly connected TFT and one reversely connected TFT which are
connected in parallel. As for the electrostatic protection unit in
FIG. 3, when the potential at the input end IP3 of the
electrostatic protection unit is higher than the potential at the
output end OP3 of the electrostatic protection unit by the
electrostatic voltage which reaches the turning-on threshold
voltage of the TFT, the forwardly connected TFT is turned on, or
when the potential at the output end OP3 of the electrostatic
protection unit is higher than the potential at the input end IP3
of the electrostatic protection unit by an electrostatic voltage
which reaches the turning-on threshold voltage of the TFT, the
reversely connected TFTs is turned on, a conductive path for
releasing electrostatic charges is formed between the input end IP3
and the output end OP3 of the electrostatic protection unit, thus
protecting the driving electrodes and the sensing electrodes
against electrostatic discharge.
[0046] FIG. 4 is a circuit diagram of a second specific
implementation of the electrostatic protection unit in FIG. 2A.
Referring to FIG. 4, the electrostatic protection unit includes two
pairs of TFTs connected in parallel. The input ends IP1 of the two
pairs of TFTs are connected together at a joint which functions as
the input end IP3 of the electrostatic protection unit, and the
output ends OP1 of the two pairs of TFTs are connected together at
a joint which functions as the output end OP3 of the electrostatic
protection unit. The input end IP3 of the electrostatic protection
unit is connected to the third external terminals 121 and the
fourth external terminals 122, and the output end OP3 of the
electrostatic protection unit is connected to the common electrode
line 123.
[0047] As for the electrostatic protection unit in FIG. 4, when the
electrostatic voltage reaches the turning-on threshold voltage of
the TFT, two parallelly connected rows of TFTs are turned on
simultaneously, where only one TFT is included in each of these two
rows of TFTs. Thus, when a conductive path for releasing
electrostatic charges is formed in electrostatic protection unit in
FIG. 4, the electrostatic protection unit in FIG. 4 can endure a
current twice as that in the case of the electrostatic protection
unit in FIG. 3, to better protect the driving electrodes and the
sensing electrodes against electrostatic discharge.
[0048] FIG. 5 is a circuit diagram of a third specific
implementation of the electrostatic protection unit in FIG. 2A.
Referring to FIG. 5, as the third specific implementation of the
electrostatic protection unit in FIG. 2A, the electrostatic
protection unit includes two serially connected pairs of TFTs. The
input end IP1 of the first pair of TFTs functions as the input end
IP3 of the electrostatic protection unit, the output end OP1 of the
first pair of TFTs is connected to the input end IP1 of the second
pair of TFTs, and the output end OP1 of the second pair of TFTs
functions as the output end OP3 of the electrostatic protection
unit. The input end IP3 of the electrostatic protection unit is
connected to the third external terminals 121 and the fourth
external terminals 122, and the output end OP3 of the electrostatic
protection unit is connected to the common electrode line 123.
[0049] As for the electrostatic protection unit in FIG. 5, when the
electrostatic voltage reaches two times the turning-on threshold
voltage of the TFT, two TFTs in the same row are turned on. Thus,
when a conductive path for releasing the electrostatic charges is
formed, the electrostatic protection unit can endure an
electrostatic voltage twice that in the case of the electrostatic
unit in FIG. 3, to better protect the driving electrodes and the
sensing electrodes against electrostatic discharge.
[0050] FIG. 6A is a second circuit diagram of the electrostatic
protection unit of the touch display panel according to an
embodiment of the present invention. FIG. 6B is a circuit diagram
of one of the TFTs in the electrostatic protection unit in FIG. 6A.
In one specific example of the present invention, referring to FIG.
6A, the electrostatic protection unit includes n parallelly
connected rows of TFTs, with each row including m serially
connected TFTs, so that the electrostatic protection unit comprises
n.times.m TFTs, where n is an odd number greater than 1 and m is a
positive integer.
[0051] Referring to FIG. 6B, a gate electrode 231 and a drain
electrode 232 of each TFT are connected together at a joint which
functions as an input end IP1 of the TFT, and a source electrode
233 of each TFT functions as an output end OP1 of the TFT.
[0052] Referring to FIG. 6A, in each of the n rows of TFTs, the
input end IP1 of each TFT except for the first TFT in the row is
connected with the output end OP1 of the preceding TFT, the input
end IP1 of the first TFT functions as the input end IP2 of the row
of TFTs, and the output end OP1 of the m-th TFT functions as an
output end OP2 of the row of TFTs.
[0053] The input ends IP2 of the first (n+1)/2 rows of TFTs and the
output ends OP2 of the remaining (n-1)/2 rows of TFTs are connected
together at a joint which functions as the input end IP3 of the
electrostatic protection unit, and the output ends OP2 of the first
(n+1)/2 rows of TFTs and the input ends IP2 of the remaining
(n-1)/2 rows of TFTs in are connected together at a joint which
functions as the output end OP3 of the electrostatic protection
unit.
[0054] The input end IP3 of the electrostatic protection unit is
connected to the third external terminals 121 and the fourth
external terminals 122, and the output end OP3 of the electrostatic
protection unit is connected to the common electrode line 123.
[0055] The principle of implementing the electrostatic protection
by the electrostatic protection unit in FIG. 6A is similar with
that in FIG. 2A, and thus will not be discussed again here.
[0056] Further, a specific implementation of the electrostatic
protection unit in FIG. 6A is given below in connection with FIG.
7. FIG. 7 is a circuit diagram of a specific implementation of the
electrostatic protection unit in FIG. 6A. Referring to FIG. 7, the
electrostatic protection unit includes three parallelly connected
rows of TFTs, with each row including two serially connected TFTs.
In each of the three rows of TFTs, the input end IP1 of the first
TFT functions as an input end IP2 of the row of TFTs, the output
end OP1 of the first TFT is connected with the input end IP1 of the
second TFT, and the output end OP1 of the second TFT functions as
an output end OP2 of the row of TFTs.
[0057] The input ends IP2 of the first two rows of TFTs and the
output end OP2 of the last row of TFTs are connected together at a
joint which function as the input end IP3 of the electrostatic
protection unit, and output ends OP2 of the first two rows of TFTs
and the input end IP2 of the last row of TFTs are connected
together at a joint which functions as the output end OP3 of the
electrostatic protection unit. The input end IP3 of the
electrostatic protection unit is connected with the third external
terminals 121 and the fourth external terminals 122, and the output
end OP3 of the electrostatic protection unit is connected with the
common electrode line 123.
[0058] FIG. 8 is a third circuit diagram of the electrostatic
protection unit of the touch display panel according to an
embodiment of the present invention. In a specific example of the
present invention, as shown in FIG. 8, the number of rows of
forwardly connected TFTs and the number of rows of reversely
connected TFTs in the electrostatic protection unit in FIG. 8 are
respectively equal to the number of rows of the reversely connected
TFTs and the number of rows of the forwardly connected TFTs in the
electrostatic protection unit in FIG. 6A, that is, in the
electrostatic protection unit, the input ends IP2 of the first
(n-1)/2 rows of TFTs and the output ends OP2 of the remaining
(n+1)/2 rows of TFTs are connected together at a joint which
functions as the input end IP3 of the electrostatic protection
unit, and the output ends OP2 of the first (n-1)/2 rows of TFTs and
the input ends IP2 of the remaining (n+1)/2 rows of TFTs are
connected together at a joint which functions as the output end OP3
of the electrostatic protection unit, where n is an odd number
greater than 1 and m is positive integer. The input end IP3 of the
electrostatic protection unit is connected with the third external
terminals 121 and the fourth external terminals 122, and the output
end OP3 of the electrostatic protection unit is connected with the
common electrode line 123.
[0059] The electrostatic protection units in FIG. 8 is different
from that in FIG. 6A in terms of the number of rows of forwardly
connected TFTs and the number of rows of reversely connected TFTs,
and hence is different in terms of endurance on the conductive
current. However, the principle of implementing the electrostatic
protection by the electrostatic protection unit in FIG. 8 is the
same with that in FIG. 6A, and will not be discussed again
here.
[0060] Further, a specific implementation of the electrostatic
protection unit in FIG. 8 is given below in connection with FIG. 9.
FIG. 9 is a circuit diagram of a specific implementation of the
electrostatic protection unit in FIG. 8. Referring to FIG. 8, the
electrostatic protection unit includes three rows of TFTs connected
in parallel with each other, with each row including two TFTs
connected in series.
[0061] The input end IP2 of the first row of TFTs and the output
ends OP2 of the remaining two rows of TFTs are connected together
at a joint which functions as the input end IP3 of the
electrostatic protection unit, and output end OP2 of the first row
of TFTs and the input ends IP2 of the remaining two rows of TFTs
are connected together at a joint which functions as the output end
OP3 of the electrostatic protection unit. The input end IP3 of the
electrostatic protection unit is connected with the third external
terminals 121 and the fourth external terminals 122, and the output
end OP3 of the electrostatic protection unit is connected with the
common electrode line 123.
[0062] Without changing the number of rows of the forwardly
connected TFTs and the number of rows of the reversely connected
TFTs, positions of the rows of the forwardly connected TFTs
relative to positions of the rows of the reversely connected TFTs
may be varied in any way in the above electrostatic protection
units shown in FIGS. 6A and 7 to 9, obtaining an electrostatic
protection unit which has the same principle and function of
electrostatic protection with those in FIGS. 6A and 7 to 9.
[0063] Further, the TFT array substrate further includes an array
of TFTs which has the same main structure with the TFTs of the
electrostatic protection unit. Considering that the array of TFTs
has a film layer structure, the TFTs of the electrostatic
protection unit have the same film layer structure as the array of
TFTs array when forming the TFTs of the electrostatic protection
unit, which is meant by "the same main structure". This allows the
manufacturing process of the TFTs of the electrostatic protection
unit to be compatible with the manufacturing process of the array
of TFTs, or even the TFTs of the electrostatic protection unit may
be formed in the same manufacturing process with the array of TFTs,
without causing additional manufacturing steps or costs.
[0064] It should be noted that although the TFTs of the
electrostatic protection unit and the TFT array may be formed in
the same manufacturing process, and the TFTs of the electrostatic
protection unit and the TFT array have the same main structure in
which the TFTs of the electrostatic protection unit have their gate
electrodes to be connected with their source or drain electrodes to
form diode structures, the TFTs of the electrostatic protection
unit needs to be disposed on a non-display region of the TFT array
substrate.
[0065] Further, a specific implementation of the electrostatic
protection unit is given below in connection with FIG. 10. FIG. 10
is a schematic diagram of the TFTs in the electrostatic protection
unit of the touch display panel according to an embodiment of the
present invention. Referring to FIG. 10, the electrostatic
protection unit includes a pair of TFTs, where the pair of TFTs
includes a first TFT and a second TFT, and the gate electrode 311
of the first TFT, the gate electrode 321 of the second TFT and all
the gate electrodes of the array of TFTs on the TFT array substrate
are located in a gate layer of the film layer structure of the TFT
array, and the drain electrode 312 and source electrode 313 of the
first TFT, the drain electrode 322 and source electrode 323 of the
second TFT, and all the drain and source electrode of the array of
TFTs are located in the drain/source layer of the film layer
structure of the TFT array.
[0066] The gate electrode 311 of the first TFT is connected with
the drain electrode 312 of the first TFT through a gate layer metal
wire 33, a via hole 34 located between the gate layer and the
source layer, and a source layer metal wire 35 in sequence. The
drain electrode 312 of the first TFT is connected with the source
electrode 323 of the second TFT through a source layer metal wire
35, and the drain electrode 312 of the first TFT is connected with
a gate layer metal wire 33 through the source metal wire 35 as well
as the via hole 34 located between the gate layer and the source
layer. The gate layer metal wire 33 functions as the input end IP3
of the electrostatic protection unit, and the electrostatic
protection unit can be connected with the third external terminals
and the fourth external terminals through the gate layer metal wire
33. The source electrode 313 of the first TFT is connected with the
drain electrode 322 of the second TFT through the source layer
metal wire 35, and the drain electrode 322 of the second TFT is
connected with the gate electrode 321 of the second TFT through the
source layer metal wire 35, the via hole 34 located between the
gate layer and the source layer, and the gate layer metal wire 33
in sequence. The gate electrode 321 of the second TFT is connected
with the source layer metal wire 35 through the gate layer metal
wire 33 as well as the via hole 34 located between the gate layer
and the source layer. The source layer metal wire 35 functions as
the output end OP3 of the electrostatic protection unit, and the
electrostatic protection unit can be connected with the common
electrode line through the source layer metal wire 35.
[0067] The specific implementation where the electrostatic
protection unit and the TFT array are formed in the same
manufacturing process has been described as above. As can be seen,
no additional manufacturing step and costs are involved. In
addition, when a conductive path is formed in the electrostatic
protection unit applied by an electrostatic voltage, the
electrostatic protection unit can protect the driving electrodes
and the sensing electrodes against electrostatic discharge.
[0068] An embodiment of the present invention also provides a
display device 1 with a touch display panel. FIG. 11 is a schematic
diagram of the structure of a display device with a touch display
panel according to an embodiment of the present invention. As shown
in FIG. 11, the display device includes the touch display panel 10
described above.
[0069] In the touch display panel and the display device with the
same as provided by the embodiments of the present invention, the
active electrostatic protection unit is provided on the TFT array
substrate, the input end of the electrostatic protection unit is
connected with the driving electrodes and the sensing electrodes
arranged on the color filter substrate, and the output end of the
electrostatic protection unit is connected with the common
electrode line arranged on the TFT array substrate, to protect the
driving electrodes and the sensing electrodes against ESD, thereby
improving the yield of the display device with a touch panel.
[0070] It should be noted that the preferred embodiments of the
present invention and the technical principles used therein are
described as above. It should be appreciated by those skilled in
the art that the present invention is not limited to the particular
embodiments described herein, and any apparent alterations,
modification and substitutions can be made by those skilled in the
art without departing from the scope of protection of the present
invention. Accordingly, while the present invention are described
in detail through the above embodiments, the present invention is
not limited to the above embodiments and can further include other
additional equivalent embodiments without departing from the
concept of the present invention. The scope of the present
invention should be subject to the appended claims.
* * * * *