KR101451578B1 - Touch Panel Liquid Crystal Display Device - Google Patents

Abstract

An in-cell type touch panel liquid crystal display device having an optical sensor has a problem that the aperture ratio is reduced due to the presence of the optical sensor in the pixel region and a problem that the aperture ratio is decreased due to the change in the photo current The present invention aims at solving the problem that the generation of the photocurrent is small and the possibility of malfunction is high.

According to an aspect of the present invention, there is provided a touch panel liquid crystal display comprising:

A gate line formed on the substrate, a data line formed to cross the gate line and defining a pixel region, a driving transistor formed at an intersection of the gate line and the data line, And a switch portion formed at an intersection of the gate line and the sensing line,

And the switch unit supplies a gate signal supplied to the gate line to the sensing line at the time of touch.

Touch panel liquid crystal display, column spacer, sensing line

Description

[0001] The present invention relates to a touch panel liquid crystal display device,

The present invention relates to a touch panel liquid crystal display device, and more particularly, to a touch panel liquid crystal display device using a new touch panel driving method by using a difference in height between column spacers that maintain a gap between two bonded substrates.

2. Description of the Related Art [0002] With the development of the information society in recent years, demands for display devices for outputting image information have been increasing in various forms. Accordingly, a liquid crystal display (LCD), a plasma display panel (PDP) Display, and VFD (Vacuum Fluorescent Display) have been researched and utilized.

The liquid crystal display device which is widely used as a portable flat panel display device due to its excellent image quality, light weight, thinness, and low power consumption and especially used in a notebook computer monitor, a television monitor, and the like is the most typical flat panel display device It will be possible.

BACKGROUND ART [0002] In recent years, electrical characteristics such as resistance and capacitance change at a touch point where a hand or a stylus pen touches a liquid crystal display device, and the touch point is sensed to output information corresponding to the touch point A touch panel liquid crystal display device in which a touch panel for performing an operation is laminated is widely used. Such a touch panel liquid crystal display device is one of user interfaces and its application range has been expanded to small portable terminals, office equipment, mobile phones and the like.

However, such a method in which a separate touch panel is laminated on a liquid crystal display device has a problem in that its thickness becomes thick, which limits its thickness, that the light transmission efficiency decreases while passing through the laminated panel, As well as the fact that it increases.

In order to solve such problems, an in-cell type touch panel liquid crystal display device having an optical sensor in a pixel region of a liquid crystal display device has been proposed. That is, an in-cell type touch panel liquid crystal display device having an optical sensor is driven in such a manner that an optical sensor senses a change in light at the time of touch and senses a touch position according to a change in the signal.

However, in the in-cell type touch panel liquid crystal display device including the optical sensor, the aperture ratio is decreased by the optical sensor being provided in the pixel region, and the change of the photo current The generation of the photocurrent is small and the possibility of a malfunction is high.

SUMMARY OF THE INVENTION The present invention has been conceived to solve such problems, and it is an object of the present invention to provide a touch sensing device capable of obtaining a high touch signal output by sensing a touch position by directly using a gate signal and a low signal to noise ratio (S / N) And to provide a touch panel liquid crystal display device capable of realizing a touch panel liquid crystal display device.

According to an aspect of the present invention, there is provided a touch panel liquid crystal display comprising:

A gate line formed on the substrate, a data line formed to cross the gate line and defining a pixel region, a driving transistor formed at an intersection of the gate line and the data line, And a switch portion formed at an intersection of the gate line and the sensing line,

And the switch unit supplies a gate signal supplied to the gate line to the sensing line at the time of touch.

According to another aspect of the present invention, there is provided a touch panel liquid crystal display device including a first substrate and a second substrate which are bonded together and facing each other,

A data line for intersecting the gate line and the gate insulating film and defining a pixel region; a driving transistor formed at an intersection of the gate line and the data line; A first column spacer formed on the second substrate so as to be in contact with the first substrate and maintaining a gap between the two substrates; and a second column spacer formed on the second substrate, A second column spacer formed to be spaced apart from the substrate, and a conductive layer formed to float above the second column spacer,

The second column spacer is contacted to the first substrate at the time of touch, so that the gate line and the sensing line are electrically connected to each other through the conductive layer.

In the touch panel liquid crystal display device according to another embodiment of the present invention, the second column spacer is contacted to the first substrate at the time of touch, and the gate line connecting electrode branched from the gate line through the conductive layer, And the sensing line connecting electrodes branched from the sensing line connecting electrodes are electrically connected to each other.

As described above, the touch panel liquid crystal display device according to the embodiment of the present invention uses a gate signal directly as a touch signal to obtain a high touch signal output and a low signal-to-noise ratio to prevent malfunction .

Further, the touch panel liquid crystal display device according to the embodiment of the present invention can easily cope with the thinness by not laminating a separate touch panel on the liquid crystal display device, and further, when passing through the laminated panel, It is possible to solve the problem that the transmission efficiency is reduced and the production cost can be reduced.

A touch panel liquid crystal display device according to an embodiment of the present invention includes a first column spacer directly contacting a first substrate and a second column spacer spaced apart from the first substrate and contacting the first substrate only at the time of touching, So that it has an effect of having strong durability against external pressure.

Hereinafter, a touch panel liquid crystal display device according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Note that the same reference numerals denote the same components hereinafter.

1 is an equivalent circuit diagram of a touch panel liquid crystal display device according to an embodiment of the present invention. A touch panel liquid crystal display device according to an embodiment of the present invention includes two substrates bonded together facing each other with a liquid crystal layer interposed therebetween. For example, a thin film transistor array and a color filter array may be formed on each substrate.

1, a touch panel liquid crystal display device according to an embodiment of the present invention includes a gate line GL for supplying a gate signal from the outside, a data line DL formed to cross the gate line, A driving transistor unit T for driving one pixel is formed at an intersection of the gate line and the data line.

The driving transistor unit includes a gate electrode connected to the gate line, a source electrode connected to the data line, and a drain electrode spaced apart from the source electrode. The driving transistor unit is connected to the drain electrode of the driving transistor unit, The liquid crystal is driven by a voltage difference between a pixel electrode (not shown) to be charged and a common electrode (not shown) to which the common voltage Vcom is supplied.

At this time, even if the gate electrode of the one pixel is turned off and the pixel voltage is not supplied to the pixel electrode, the liquid crystal between the pixel electrode and the common electrode acts as a capacitor having the capacitance C _LC , While maintaining the image for the frame.

In addition, a sensing line SL is formed to cross the gate line. A switch SW for supplying a gate signal to the sensing line at the time of touch is formed at an intersection of the sensing line and the gate line.

Next, the touch panel liquid crystal display device according to the first embodiment of the present invention will be described in more detail with reference to FIG. 2 to FIG. FIG. 2 is a plan view showing a pixel of a first substrate on which a thin film transistor array of a touch panel liquid crystal display according to a first embodiment of the present invention is formed, FIG. 3 is a cross- And FIG. 4 is a cross-sectional view taken along the line II-II 'in FIG. In FIG. 4, only the second substrate and the column spacer are illustrated, omitting the illustration of other layers formed on the second substrate for convenience of explanation.

2 to 4, the touch panel liquid crystal display device according to the first embodiment of the present invention includes a gate line 110 formed on the first substrate 101, the gate line, A data line 120 which intersects the gate line and the gate insulating film to define a pixel region P and a data line 120 which is parallel to the gate line or the data line on the first substrate A driving transistor formed at an intersection of the gate line and the data line; a second transistor formed on the second substrate to be in contact with the first substrate to maintain a gap between the two substrates; A second column spacer 154 formed on the second substrate to be spaced apart from the first substrate 101, and a second column spacer 154 formed on the second column spacer, And a conductive layer 155.

In addition, a passivation 180 formed to cover the entire surface of the substrate including the driving transistor and the data line, and a pixel electrode 160 formed on the passivation layer and connected to the driving transistor, .

The driving transistor unit includes a gate electrode 112 formed by branching from the gate line to a pixel region, a semiconductor layer 126 formed above the gate electrode with a gate insulating film interposed therebetween, And a source electrode 122 formed on one side of the source electrode 122 and a drain electrode 124 formed apart from the source electrode. The pixel electrode 160 may be connected to the drain electrode through a pixel electrode contact hole 146 formed by removing a part of the protective film to expose the drain electrode.

In addition, a protrusion pattern 128 may be formed on the gate line. The protrusion pattern may be formed by stacking, for example, a first semiconductor layer 126a formed of the same layer as the semiconductor layer and a metal layer 128a formed of the same layer as the data line over the gate insulating layer, And the first column spacer 152 formed on the first substrate 150 contacts the first substrate.

In addition, the sensing line 130 may be formed of the same layer as the data line, and the second semiconductor layer 126b may be formed of the same layer as the semiconductor layer.

For example, the conductive layer 155 may be formed of the same layer as the common electrode formed on the second substrate. Indium Tin Oxide (ITO), Indium Zinc Oxide : IZO), or may be formed of an opaque metal material.

Although the conductive layer is formed to be floated and is formed to cover only the upper portion of the second column spacer in the drawing, it may be formed so as to cover the side surface of the second column spacer. As such, if the second column spacer is formed so as to cover the side surface of the second column spacer, the area that can be contacted at the time of touch can be increased.

In addition, in the first substrate, a first contact hole 142 is formed in a region corresponding to the second column spacer formed on the second substrate, the gate insulating film and the protective film being simultaneously removed to expose the gate line, A second contact hole 144 formed by removing the protective film to expose the sensing line is formed.

4, the first column spacer having the first height h1 is formed in a region corresponding to the protrusion pattern 128 formed on the gate line 110 in the second substrate, And serves to maintain a cell gap between the first substrate 101 and the second substrate 102 by contacting the first substrate.

Also, although not shown, it is also possible to form the first column spacer so as to be in contact with the first substrate without providing a separate projection pattern on the first substrate.

On the other hand, the second column spacer is formed to have a second height h2 smaller than the first height h1, and unlike the first column spacer, the second column spacer is spaced apart from the first substrate by a predetermined distance g Respectively.

As described above, the first column spacer and the second column spacer having different heights can be formed by using, for example, a diffraction exposure mask using a diffraction phenomenon of light or a halftone mask using difference in light transmittance .

5, when the second column spacer 154 spaced apart from the first substrate receives a pressure during a touch operation, the first contact hole 154 is formed in the first contact hole 154. In other words, when the touch panel liquid crystal display device according to the first exemplary embodiment of the present invention is pressed, And a sensing line 130 exposed through the second contact hole are electrically connected through a conductive layer 155 formed by floating on top of the second column spacer, A gate signal supplied to the sensing line is supplied to the sensing line.

In general, since the column spacer is formed of a photoresist made of an organic material, the column spacer has elasticity, so that it can be bent by a pressure applied at the time of touching, or pressed to a predetermined thickness according to the shape of the lower pattern.

As described above, in the touch panel liquid crystal display device according to the first embodiment of the present invention, the second column spacer formed on the second substrate so as to be spaced apart from the first substrate functions as a switch, So that the touch position can be detected through a touch signal having a high signal output and a low signal-to-noise ratio as compared with an optical sensor using a photocurrent.

6 is a cross-sectional view showing another example of a touch panel liquid crystal display device according to the first embodiment of the present invention. In the touch panel liquid crystal display device according to the first embodiment of the present invention, as shown in FIG. 6, a first connection electrode 162 and a second contact hole 144 formed to cover the first contact hole 142 are covered The second connection electrode 164 may be formed to include the first connection electrode 164 and the second connection electrode 164.

The first contact hole and the second contact hole may be formed at the same time as the pixel electrode contact hole and the first connection electrode 162 and the second connection electrode 164 are preferably formed on the pixel electrode 160 may be formed of the same layer.

Next, a touch panel liquid crystal display device according to a second embodiment of the present invention will be described with reference to FIGS. 7 to 8. FIG.

FIG. 7 is a plan view of a pixel of a touch panel liquid crystal display device according to a second embodiment of the present invention, and FIG. 8 is a cross-sectional view of III-III 'in FIG.

7 and 8, the touch panel liquid crystal display device according to the second embodiment of the present invention includes a gate line 110 formed on the first substrate 101, the gate line, A data line 120 which intersects the gate line and the gate insulating film to define a pixel region P and a data line 120 which is parallel to the gate line or the data line on the first substrate A driving transistor formed at an intersection of the gate line and the data line; a second transistor formed on the second substrate to be in contact with the first substrate to maintain a gap between the two substrates; A second column spacer 154 formed on the second substrate to be spaced apart from the first substrate 101, and a second column spacer 154 formed on the second column spacer, It is configured to include the conductive layer 155 and the gate is branched to the pixel region from the gate line formed connection electrode 172 and the sensing lines connected to the electrode 174 is branched into a pixel region formed from the sensing line.

In addition, a passivation 180 formed to cover the entire surface of the substrate including the driving transistor and the data line, and a pixel electrode 160 formed on the passivation layer and connected to the driving transistor, .

The driving transistor unit includes a gate electrode 112 formed by branching from the gate line to a pixel region, a semiconductor layer 126 formed above the gate electrode with a gate insulating film interposed therebetween, A source electrode 122 formed on one side of the layer, and a drain electrode 124 formed apart from the source electrode. The pixel electrode 160 may be connected to the drain electrode through a pixel electrode contact hole 146 formed by removing a part of the protective film to expose the drain electrode.

In addition, a protrusion pattern 128 may be formed on the gate line. The protrusion pattern may be formed, for example, by stacking a first semiconductor layer formed of the same layer as the semiconductor layer and a metal layer formed of the same layer as the data line over the gate insulating film, and a first column spacer So that the first substrate 152 contacts the first substrate.

In addition, the sensing line 130 may be formed of the same layer as the data line, or the second semiconductor layer may be formed of the same layer as the semiconductor layer.

For example, the conductive layer 155 may be formed of the same layer as the common electrode formed on the second substrate, and may be formed of indium tin oxide (ITO) or indium zinc oxide IZO), or it may be formed of an opaque metal material.

Although the conductive layer is formed to be floated and is formed to cover only the upper portion of the second column spacer in the drawing, it may be formed so as to cover the side surface of the second column spacer. As such, if the second column spacer is formed so as to cover the side surface of the second column spacer, the area that can be contacted at the time of touch can be increased.

The first column spacer 152 formed on the second substrate may include a protrusion pattern 128 formed on the gate line and a second substrate 152 corresponding to the protrusion pattern 128 formed on the gate line similarly to the touch panel liquid crystal display device according to the first embodiment of the present invention. As shown in Fig.

For example, the protrusion pattern may be formed by stacking a first semiconductor layer formed of the same layer as the semiconductor layer and a metal layer formed of the same layer as the data line on the gate insulating film, And serves to form a step so that one column spacer 152 can be brought into contact with the first substrate.

In the first substrate, a gate line connection electrode branched from the gate line to the pixel region and a pixel region branched from the sensing line are formed in a region corresponding to the second column spacer 154 formed on the second substrate A sensing line connecting electrode is formed. At this time, the gate insulating layer and the protecting layer are simultaneously removed to expose the gate line connecting electrode, thereby forming the first contact hole 142. The protective layer is removed to expose the sensing line connecting electrode, and the second contact hole 144 And the second column spacer is formed in a region of the second substrate corresponding to the first contact hole and the second contact hole.

As described above, the first column spacer which directly contacts the first substrate and maintains the cell gap, and the second column spacer which is formed so as not to come in direct contact with the first substrate but contacts the first substrate only at the time of touch, It can be formed using a resist, for example, by using a diffraction exposure mask using diffraction of light or a halftone mask using difference in light transmittance.

In the touch panel liquid crystal display device according to the second embodiment of the present invention, the second column spacer 154 formed on the second substrate is normally formed in a region corresponding to the upper portion of the gate line connecting electrode and the sensing line connecting electrode The gate line connection electrode and the sensing line connection electrode are electrically connected to each other through a conductive layer formed to float above the second column spacer at the time of touch, The supplied gate signal is supplied to the sensing line.

Meanwhile, in the touch panel liquid crystal display device according to the first embodiment of the present invention, as shown in FIG. 4, the second column spacer contacts the sensing line through a region where the gate line 110 overlaps with the sensing line.

On the other hand, in the touch panel liquid crystal display device according to the second embodiment of the present invention, as shown in FIG. 8, since the sensing line connecting electrode is formed in the region without the gate line, . As such, when the step between the gate line connecting electrode and the sensing line connecting electrode to which the second column spacer is contacted is reduced, it is possible to electrically connect the gate line and the sensing line even with less deformation of the second column spacer .

That is, since the gate signal supplied to the gate line can be supplied to the sensing line through a small deformation of the second column spacer, it becomes possible to realize a touch panel liquid crystal display device with high sensitivity.

9 is a cross-sectional view showing another example of a touch panel liquid crystal display device according to a second embodiment of the present invention. In the touch panel liquid crystal display device according to the second embodiment of the present invention, as shown in FIG. 9, a first connection electrode 162 and a second contact hole 144 formed to cover the first contact hole 142 are covered The second connection electrode 164 may be formed to include the first connection electrode 164 and the second connection electrode 164.

The first contact hole and the second contact hole may be formed at the same time as the pixel electrode contact hole and the first connection electrode 162 and the second connection electrode 164 are preferably formed on the pixel electrode 160 may be formed of the same layer.

As described above, in the touch panel liquid crystal display device according to the second embodiment of the present invention, when the first connection electrode is formed to cover the first contact hole and the second connection electrode is formed to cover the second contact hole, As shown in FIG. 9, since the region having no step difference is formed between the first connection electrode and the second connection electrode, it is possible to realize a touch panel liquid crystal display device having higher sensitivity.

As described above, in the case of the conventional optical sensor using a photo current, since the magnitude of the current is low, a touch signal processing unit including amplifiers for amplifying a signal is separately required. However, in the touch panel liquid crystal display Since the device uses a gate signal having a strength several tens of times stronger than a photocurrent as a touch signal, it becomes possible to realize a touch panel liquid crystal display device with high sensitivity.

10 is a graph showing the intensity of the gate line signal (dotted line) and the voltage intensity of the touch signal (solid line) with time. As can be seen from FIG. 10, the intensity of the touch signal rises to the gate high voltage (Vgh) level, and in terms of the response speed, there is almost no delay phenomenon as compared with the gate signal.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Will be apparent to those of ordinary skill in the art.

1 is an equivalent circuit diagram of a touch panel liquid crystal display device according to an embodiment of the present invention.

2 is a plan view showing a pixel of a first substrate on which a thin film transistor array of a touch panel liquid crystal display device according to a first embodiment of the present invention is formed;

3 is a cross-sectional view showing a cross section of drive transistor portions I to I 'in FIG. 2;

4 is a sectional view showing a cross section of II-II 'in FIG. 2;

5 is a cross-sectional view showing a case where the second column spacer undergoes pressure upon touching the gate line and the sensing line of the first substrate.

6 is a sectional view showing still another example of a touch panel liquid crystal display device according to the first embodiment of the present invention.

7 is a plan view showing a pixel of a touch panel liquid crystal display device according to a second embodiment of the present invention.

8 is a sectional view showing a cross section of III-III 'in Fig. 7;

9 is a sectional view showing still another example of a touch panel liquid crystal display device according to a second embodiment of the present invention.

10 is a graph showing the intensity of a gate line signal (dotted line) and the voltage intensity of a touch signal (solid line) with time.

 Description of the Related Art

GL: gate line DL: data line

SL: sensing line T: driving transistor section

SW: switch portion P: pixel region

101: first substrate 102: second substrate

110: gate line 112: gate electrode

115: gate insulating film 120: data line

122: source electrode 124: drain electrode

126: semiconductor layer 126a: first semiconductor layer

126b: second semiconductor layer 128: projection pattern

128a: metal layer 130: sensing line

142: first contact hole 144: second contact hole

146: pixel electrode contact hole 152: first column spacer

154: second column spacer 160: pixel electrode

162: first connection electrode 164: second connection electrode

155: conductive layer 180:

172: gate line connecting electrode 174: sensing line connecting electrode

Claims (10)

delete A touch panel liquid crystal display comprising a first substrate and a second substrate bonded together facing each other, A gate line formed on the first substrate and a data line crossing the gate line and the gate insulating layer to define a pixel region; A driving transistor formed at an intersection of the gate line and the data line; A sensing line formed on the first substrate so as to be in parallel with the data line; A first column spacer formed on the second substrate in contact with the first substrate to maintain a gap between the two substrates; A second column spacer spaced apart from the first substrate on the second substrate; And And a conductive layer formed to float above the second column spacer, The second column spacer being in contact with the first substrate at the time of touch so that the gate line and the sensing line are electrically connected to each other through the conductive layer; The gate line and the sensing line are exposed through a first contact hole and a second contact hole formed by removing at least one of a gate insulating layer and a protective layer, and the second column spacer is exposed through a first contact hole The exposed gate lines and the sensing lines exposed through the second contact holes are electrically connected to each other. 3. The method of claim 2, A protective film covering the entire surface of the substrate including the data line and the sensing line; And And a pixel electrode formed on the passivation layer so as to be connected to the driving transistor unit. delete 3. The method of claim 2, A gate line connection electrode branched from the gate line to the pixel region; and a sensing line connection electrode branched from the sensing line to the pixel region, The gate line connecting electrode and the sensing line connecting electrode are exposed through the first contact hole and the second contact hole formed by removing at least one of the gate insulating layer and the protecting layer and the second column spacer is exposed through the first contact hole, The gate line connecting electrode exposed through the hole and the sensing line connecting electrode exposed through the second contact hole are electrically connected to each other. 6. The method of claim 5, A first connection electrode formed to cover the first contact hole, and a second connection electrode formed to cover the second contact hole. The method according to claim 6, Wherein the first connection electrode and the second connection electrode are formed in the same layer as the pixel electrode. 3. The method of claim 2, Wherein the sensing line is formed in the same layer as the data line. 3. The method of claim 2, And the conductive layer on the second column spacer is formed of the same layer as the common electrode formed on the second substrate. 3. The method of claim 2, And a protrusion pattern formed in the same layer as the data line is formed in an area where the first column spacer contacts the first substrate.

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