TW201413323A - In-plane switching liquid crystal display device for improving accuracy of touch positions - Google Patents

Abstract

The invention provides an in-plane switching liquid crystal display device for improving accuracy of touch positions, and includes a plurality of gate wires and data wires, at least one thin-film transistor, a plurality of pixel electrodes, a plurality of common electrodes and a plurality of sensor wirings. The plurality of gate wires and data wires are provided on a first substrate and mutually intersecting to define subpixels of Red, Green and Blue. The plurality of pixel electrodes and common electrodes are mutually separated to be alternately configured on the Red, Green and Blue subpixel of the first substrate. Sensors are formed after the common electrodes and common wires are patterned. The plurality of sensor wirings are located between the data wires and the first substrate, and have their positions arranged with respect to those of the plurality of data wires, wherein each of the sensor wirings is connected to a sensor.

Description

Planar switching liquid crystal display device with increased touch position accuracy

The present invention relates to the technical field of touch panels, and more particularly to a planar switching liquid crystal display device that increases the accuracy of touch position.

The liquid crystal display device can operate at a lower energy consumption and higher definition than the cathode ray tube, and it can be manufactured to a smaller size and a larger size, and thus is considerably welcomed. It mainly changes the optical characteristics through an electric field applied to the liquid crystal to operate the liquid crystal display device. According to the characteristics of the liquid crystal and the structure of the liquid crystal pattern, the liquid crystal display device can be classified into a twisted nematic (TN), a multi-region, an optically compensated polyrefracting (OCB), and a planar switching (In- Plane Switching (IPS) and Vertical Alignment (VA).

In a twisted nematic (TN) liquid crystal display device, a liquid crystal director is set to be twisted by 90 degrees and applied through an electric field to control the director; the multi-region liquid crystal display device operates to divide pixels into a plurality of regions. To change the direction of the main viewing angle in each area, and thus provide a wide viewing angle. In an optically compensated multi-refractive (OCB) liquid crystal display device, a compensation film is attached to the outer surface of the substrate to compensate for the phase change of the light. In a planar switching (IPS) liquid crystal display device, two electrodes are formed on a substrate, so that the liquid crystal director twisted in a plane is parallel to the alignment layer. Vertical match The transmissive (VA) liquid crystal display device is perpendicular to the alignment layer by using the cathode liquid crystal, thereby allowing the long axes of the liquid crystal molecules to be vertically arranged in a plane of the alignment layer.

1 is a plan view of a conventional planar switching liquid crystal display device, and FIG. 2 is a cross-sectional view of FIG. 1 taken along the line I-I.

As shown in FIG. 1 and FIG. 2, the planar switching liquid crystal display device includes a second substrate (color filter layer substrate or upper substrate) 21 and a first substrate (film array substrate or lower substrate) 11 disposed opposite to each other. There is a liquid crystal layer 31 between the two. In addition, a black matrix 22 is formed on the upper substrate to prevent light leakage, and a color filter layer 23 is formed on the black matrix 22, which is composed of red, green and blue color protective layers to exhibit color.

The gate line 12 is disposed perpendicular to the data line 15 and intersects the lower substrate 11, thereby defining a pixel, a thin film transistor TFT, a common line 25, a plurality of common electrodes 24, a plurality of pixel electrodes 17, and a capacitor electrode 26. The thin film transistor TFT is disposed at an intersection of the gate line 12 and the data line 15, and the common line 25 is disposed in each pixel and parallel to the gate line 12.

A plurality of common electrodes 24 are branched from the common line 25 and parallel to the data line 15, and each of the pixel electrodes 17 is connected to each of the drains of the thin film transistor TFT, and is alternately disposed between the common electrodes 24 and the common electrode 24 are parallel to each other. The capacitor electrode 26 is formed by extending the respective pixel electrodes 17 and covers the upper portion of the common line 25. The common electrode 24 and the pixel electrode 17 are alternately arranged to cross each other and generate a transverse electric field.

Each of the thin film transistors TFT includes a gate 12a, a gate insulating layer (not shown), a semiconductor layer 14, and a source 15a and a drain 15b. The gate 12a is branched from the respective gate lines 12, the gate insulating layer is formed on the entire surface including the gate 12a, and the semiconductor layer 14 is formed on the gate insulating layer on the gate 12a, and the source 15a The drain 15b is branched by each of the data lines 15 and formed at both ends of the semiconductor layer 14.

Each of the pixel electrodes 17 is connected to the drain 15b through a drain contact hole 19. Further, each of the common lines 25 and the common electrode 24 are formed as a unitary structure and simultaneously formed in the gate line 12. Each of the common lines 25 and the common electrode 24 may be formed of a low-resistance metal such as copper (Cu), aluminum (Al), chromium (Cr), molybdenum (Mo), and titanium (Ti).

The pixel electrode 17 and the common electrode 24 are formed alternately with each other, wherein the pixel electrode 17 may be formed simultaneously with the data line 15 or formed in a different layer from the data line 15, and the common electrode 24 and the pixel electrode 17 may alternate with each other. Form a straight line or form a sawtooth pattern.

The common electrode 24 and the pixel electrode 17 may be formed of a transparent conductor metal having a desired light transmittance, such as Indium-Tin-Oxide (ITO).

As shown in FIG. 2 , an insulating layer 13 is further disposed between the common electrode 24 and the pixel electrode 17 to electrically isolate the common electrode 24 and the pixel electrode 17 . Reference numeral 13 in Fig. 2 denotes a gate insulating layer formed of tantalum nitride or hafnium oxide.

The common electrode 24 may be first formed as described above, the pixel electrode 17 may be formed later, and then an insulating layer may be filled between the common electrode 24 and the pixel electrode 17 to electrically isolate the common electrode 24 from the pixel electrode 17. Or, first, the pixel electrode 17 is formed, and later the common electrode 24 is formed, and then An insulating layer is filled between the two to isolate the common electrode 24 and the pixel electrode 17. Further, the common electrode 24 and the pixel electrode 17 may be formed of the same layer without intervening in the insulating layer. A protective layer 16 is further formed on the entire surface including the pixel electrode 17 to protect various patterns.

Referring to FIG. 2, the black matrix 22 is disposed on the upper substrate (ie, the color filter layer substrate) 21 to prevent light leakage, and is disposed on each of the color filter layers 23 including red, green, and blue color protective layers. Between black matrices 22. A protective layer 29 is disposed on the color filter layer 23 to protect the color filter layer 23 and planarize the surface of the color filter layer 23.

The substrate 11 and the upper substrate (color filter layer substrate) 21 of the planar switching type liquid crystal display device are connected through a sealant having adhesive characteristics, and as shown in FIG. 2, the liquid crystal layer 31 is formed on the two substrates. between.

According to the planar switching liquid crystal display device having the above structure, the common electrode 24 and the pixel electrode 17 are both formed on the same substrate for rotating the liquid crystal molecules 32 while keeping the liquid crystal molecules 32 parallel to the lower substrate 11 and applying a voltage thereto. Between the two electrodes to create a transverse electric field associated with the lower substrate 11. The resulting transverse electric field reduces the birefringence change of the liquid crystal with respect to a viewing direction. Therefore, the planar switching type liquid crystal display device provides a satisfactory viewing angle characteristic as compared with the twisted nematic liquid crystal display device of the prior art.

However, when a touch-switching liquid crystal display device is required to provide a touch function, the conventional planar switching liquid crystal display device directly superimposes the touch panel and the planar switching liquid crystal display device. Since the laminated touch panel is a transparent panel, the image can be displayed through the touch panel superimposed on the touch panel, and then the touch panel is used as an input medium or interface. However, this conventional technique is required to increase the total weight of a touch panel when superimposing, so that the weight of the planar switching type liquid crystal display device is greatly increased, which does not meet the requirements of the current market for the lightness and thickness of the display. When the touch panel and the flat display are directly stacked, the thickness of the touch panel itself is increased, the light transmittance is reduced, the reflectance and the haze are increased, and the quality of the screen display is greatly reduced.

In response to the aforementioned shortcomings, the touch-type planar switching liquid crystal display device adopts an embedded touch technology. The main development direction of embedded touch technology can be divided into On-Cell and In-Cell technologies. On-Cell technology is a structure in which a sensing electrode of a projected capacitive touch technology is fabricated on the back side of a color filter (CF) of a panel (ie, attached to a polarizing plate surface) and integrated into a color filter layer. .

In Cell touch technology integrates touch components into the display panel, so that the display panel itself has a touch function, so there is no need to separately perform a process of bonding or assembling with the touch panel, so the technology is usually Developed by the panel factory.

However, regardless of the In Cell touch technology, the On Cell touch technology, or the Out Cell touch technology, the sensing electrode layer is disposed on the upper glass substrate or the lower glass substrate of the display panel, which not only increases the cost, but also increases the process procedure, and is easy. This leads to a reduction in process yield and a rise in process costs, as well as a need for a stronger backlight with a lower aperture ratio, which also increases power consumption, which is detrimental to the thin and light requirements of mobile devices.

In order to solve the above problems, a conventional technique is to provide a transparent sensing electrode layer under the black matrix 22. The transparent sensing electrode layer and the sharing The electrodes 24 have a distance therebetween. When the transparent sensing electrode layer is subjected to touch sensing, the capacitance formed by the finger and the transparent sensing electrode layer is much smaller than the capacitance formed by the transparent sensing electrode layer and the common electrode 24. At this time, when the touch detection performed by the transparent sensing electrode layer calculates the coordinate position, the difference in the value obtained by the different sensing electrodes becomes small, which is disadvantageous for the coordinate calculation. That is, the capacitance between the transparent sensing electrode and the finger is much smaller than the capacitance between the transparent sensing electrode and the common electrode 24, and therefore, the capacitance between the transparent sensing electrode and the finger is easily affected by the transparent sensing electrode and the common electrode 24. The effect of the capacitance between them is such that the accuracy of the touch sensing is greatly affected. There is still room for improvement in the technology of the conventional capacitive touch panel.

The object of the present invention is to provide a planar switching liquid crystal display device with increased touch position accuracy, which can greatly reduce the weight and thickness of the touch plane switching liquid crystal display device, and can greatly save material cost and improve touch. The accuracy of the touch sensing.

According to a feature of the present invention, a planar switching liquid crystal display device for increasing touch position accuracy includes a plurality of gate lines and data lines, at least one thin film transistor, a plurality of pixel electrodes, and a plurality of The common electrode and the plurality of sensing electrodes are routed. The plurality of gate lines and data lines are disposed on a first substrate and intersect each other to define red, green and blue sub-pixels. The at least one thin film electro-crystal system is disposed at an intersection of the gate line and the data line. The plurality of pixel electrodes and the plurality of common electrodes Separating and alternately disposed on the red, green, and blue sub-pixels of the first substrate, the plurality of common electrodes constitute a plurality of sensing electrodes, and each of the sensing electrodes is composed of a plurality of the common electrodes. The plurality of sensing electrode traces are located between the data line and the first substrate, and each of the sensing electrode traces is connected to a sensing electrode; wherein the positions of the plurality of sensing electrode traces are based on the plurality of strips The position of the data line is set correspondingly.

FIG. 3 is a schematic diagram of a planar switching liquid crystal display device 300 of the present invention for increasing touch position accuracy. Figure 4 is a schematic illustration of one of the pixels of the present invention. Figure 5 is a cross-sectional view of Figure 4 taken along the line J-J'.

For the planar switching liquid crystal display device of the present invention for increasing the accuracy of the touch position, please refer to the planar switching liquid crystal display device 300 for increasing the touch position accuracy of the present invention shown in FIG. 3, FIG. 4 and FIG. As shown in the figure, the planar switching liquid crystal display device 300 for increasing the accuracy of the touch position includes a first substrate 11 , a second substrate 21 , a plurality of gate lines 12 and a data line 15 , and at least one thin film battery. The crystal 41, the plurality of pixel electrodes 17 and the plurality of common electrodes 24, and a plurality of sensing electrode traces 51, the liquid crystal layer 31, the color filter layer 23, the black matrix 22, the protective layer 16, the protective layer 29, and the insulating layer 13.

The first substrate 11 and the second substrate 21 are preferably glass substrates. The first substrate 11 and the second substrate 21 are disposed in parallel pairs, and the liquid crystal layer 31 is sandwiched between the two substrates 11 and 21. .

The plurality of gate lines 12 and the data lines 15 are disposed on the first substrate 11 and intersect each other to define red, green and blue sub-pixels. The at least one thin film transistor 41 is disposed at an intersection of the gate line 12 and the data line 15. The plurality of pixel electrodes 17 and the plurality of common electrodes 24 are separated from each other and alternately disposed on the red, green, and blue sub-pixels of the first substrate 11. The common electrode 24 and the pixel electrode 17 are formed in a straight line or a zigzag shape. A driving circuit (not shown) is configured to provide at least one pixel voltage level to generate a horizontal electric field between the common electrode 24 and the pixel electrode 17 in the sub-pixel. The black matrix (BM) 22 is disposed at a boundary between the sub-pixels and the thin film transistor 41.

The plurality of common electrodes 24 constitute a plurality of sensing electrodes 310, that is, each sensing electrode 310 is composed of a plurality of the common electrodes 24. Each of the plurality of sensing electrodes 310 includes 3n×m sub-pixels, of which n and m are natural numbers. As shown in FIG. 3, m=2. In other embodiments, m may be other natural numbers.

As shown in FIG. 5 , the plurality of sensing electrode traces 51 are located between the data line 15 and the first substrate 11 , and each of the sensing electrode traces 51 is electrically connected to a common line 25 via a through hole 52 . The position of the plurality of sensing electrode traces 51 is set according to the position of the plurality of data lines 15. The width of the plurality of sensing electrode traces 51 is slightly smaller than the width of the plurality of data lines 15. The plurality of sensing electrode traces 51 are made of a conductive metal material or an alloy material. Wherein, the conductive metal material is one of the following: chromium, bismuth, aluminum, copper.

As shown in FIG. 5, when viewed from the second substrate 21 toward the first substrate 11, the sensing electrode traces 51 are located below the data line 15, and the sensing electrode traces 51 are made of a conductive metal material or alloy material. The impedance of the inductive electrode trace 51 can be relatively thin and can be disposed below the data line 15 without affecting the aperture ratio.

In the same pixel row, conventional common electrodes are electrically connected via a common line. In the present invention, only the common lines in the sensing electrodes 310 are electrically connected, and the common lines in the different sensing electrodes 310 are not electrically connected. The common electrode 24 in each of the sensing electrodes 310 is electrically connected using a common line 25, and the common line 25 in each of the sensing electrodes is turned on, and the common line in the different sensing electrodes is non-conductive. As shown in FIG. 3, the common lines 25, 1 and 25, 2 in the sensing electrodes 310, 1 are turned on, and the common lines 25, 3 and 25, 4 in the sensing electrodes 310, 2 are turned on, and the sensing electrodes 310, 1 The common lines 25, 1 and 25, 2 in the middle and the common lines 25, 5 and 25, 6 in the sensing electrodes 310, 2 are non-conducting, whereby a plurality of sensing electrodes can be formed in the direction of the row 310.

The common lines 25 of different rows in the same sensing electrode 310 are electrically connected via the vias 52 and the sensing electrode traces 51. As shown in FIG. 3, the common lines 25, 1 and 25, 2 in the sensing electrodes 310, 1 and the common lines 25, 3 and 25, 4 in the sensing electrodes 310, 1 pass through the through holes 52 and the sensing electrode traces 51. And electrical connection. Meanwhile, as shown in FIG. 3, the through holes 52 of the sensing electrodes 310, 3 are disposed on the left side of the second sensing electrode trace 51, thereby making the transparent The inductive electrical signal of the sensing electrode 310 is transmitted to the controller (not shown) via the sensing electrode trace 51.

As shown in FIG. 3, the size of the transparent sensing electrode 310 is about 5 mm, and the size of one sub-pixel is about 50-100 μm. Therefore, one side of one transparent sensing electrode 310 may correspond to 50 to 100 sub-pixels. That is, one side of one transparent sensing electrode 310 may correspond to hundreds of data lines 15. In the present invention, the width of the sensing electrode trace 51 is slightly smaller than the width of the data line 15.

In the present invention, the conventional common electrode 24 and the common line 25 are patterned to form the sensing electrode 310, and the sensing electrode trace 51 is disposed opposite to the data line 15. That is, the position of the plurality of sensing electrode traces 51 is overlapped with the data line 15 to transmit the inductive electrical signal of the transparent sensing electrode 310 to the controller (not shown) via the sensing electrode trace 51 to determine the touch. position. In the present invention, a plurality of transparent sensing electrodes 310 are formed by patterning processing using a common common electrode 24 and a common line 25, and a plurality of sensing electrode traces 51 are used to transmit the inductive electrical signals of the transparent sensing electrodes 310 to A controller. In this way, it is not necessary to add a sensing electrode layer to the upper glass substrate or the lower glass substrate of the LCD display panel, thereby reducing the procedure and cost of bonding each layer, and reducing the material cost.

When the pixel data is to be displayed, the controller can electrically connect a plurality of transparent sensing electrodes 310 of the same row, as shown in FIG. 3, such that a plurality of transparent sensing electrodes 310 of the same row are A conventional common electrode (Vcom) can be formed.

In the prior art, the sensing electrode layer and the common electrode layer are respectively disposed with a distance therebetween. When the transparent sensing electrode is performing touch sensing, The capacitance between the transparent sensing electrode and the finger is much smaller than the capacitance between the transparent sensing electrode and the common electrode layer. Therefore, the capacitance between the transparent sensing electrode and the finger is easily affected by the capacitance between the transparent sensing electrode and the common electrode layer. The accuracy of touch sensing is greatly affected. In the present invention, since the transparent sensing electrode 310 is composed of a conventional common electrode 24 and a common line 25, when the transparent sensing electrode 310 performs touch sensing, the transparent sensing electrode 310 uses a plurality of sets of the common electrode 24 And the common line 25 is arranged in combination, so that the capacitance between the transparent sensing electrode 310 and the finger (not shown) is not easily affected by the capacitance between the transparent sensing electrode and the common electrode layer, so that the touch sensing can be improved. Accuracy.

The color filter 23 is located on the surface of the black matrix 22 on the same side with respect to the liquid crystal layer 31. The color filter 23 has red, green, and blue color filter layers respectively corresponding to the red, green, and blue sub-pixels disposed on the second substrate.

As can be seen from the above description, the present invention is a pattern in which a plurality of transparent sensing electrodes 310 of a single layer are formed by patterning the common electrode 24 and the common line 25, which has the advantage of not requiring an upper glass substrate or a lower glass of the LCD display panel. The substrate is increased in the provision of the sensing electrode layer, thereby reducing the cost. At the same time, the sensing electrode 310 is formed by using a plurality of sets of the common electrode 24 and the common line 25, so that the transparent sensing electrode 310 is between the transparent sensing electrode 310 and the finger (not shown) when performing the touch sensing. The capacitance is not easily affected, so the accuracy of the touch sensing can be improved.

From the above, it can be seen that the present invention is extremely useful in terms of its purpose, means, and efficacy, both of which are different from those of the prior art. Only note It is intended that the above-described embodiments are only intended to be illustrative, and the scope of the invention is intended to be limited by the scope of the appended claims.

11‧‧‧First substrate

21‧‧‧second substrate

31‧‧‧Liquid layer

22‧‧‧Black matrix

23‧‧‧Color filter layer

12‧‧ ‧ gate line

15‧‧‧Information line

TFT‧‧‧thin film transistor

25‧‧‧Shared line

24‧‧‧Multiple common electrodes

17‧‧‧Multiple pixel electrodes

26‧‧‧Capacitance electrode

12a‧‧‧ gate

14‧‧‧Semiconductor layer

15a‧‧‧ source

15b‧‧‧汲polar

19‧‧‧Bungee contact hole

13‧‧‧Insulation

16‧‧‧Protective layer

29‧‧‧Protective layer

31‧‧‧Liquid layer

32‧‧‧liquid crystal molecules

300‧‧‧Flat-switching liquid crystal display device with increased touch position accuracy

41‧‧‧ at least one thin film transistor

51‧‧‧Many sensing electrode traces

310‧‧‧Many sensing electrodes

52‧‧‧through hole

310, 1, 310, 2, 310, 3‧‧‧ sensing electrodes

25,1,25,2,25,3,25,4,25,5,25,6‧‧‧ shared lines

1 is a plan view of a conventional planar switching type liquid crystal display device.

Figure 2 is a cross-sectional view of Figure 1 taken along the line I-I.

FIG. 3 is a schematic diagram of a planar switching liquid crystal display device with increased touch position accuracy according to the present invention.

Figure 4 is a schematic illustration of one of the pixels of the present invention.

Figure 5 is a cross-sectional view of Figure 4 taken along the line J-J'.

300‧‧‧Flat-switching liquid crystal display device with increased touch position accuracy

310, 1, 310, 2, 310, 3‧‧‧ sensing electrodes

25,1,25,2,25,3,25,4,25,5,25,6‧‧‧ shared lines

52‧‧‧through hole

Claims (13)

A planar switching liquid crystal display device for increasing touch position accuracy includes: a plurality of gate lines and data lines disposed on a first substrate and crossing each other to define red, green, and blue sub-pixels; a thin film transistor is disposed at an intersection of the gate line and the data line; a plurality of pixel electrodes and a plurality of common electrodes are separated from each other and alternately disposed on the red, green, and blue sub-pixels of the first substrate The plurality of common electrodes form a plurality of sensing electrodes, each sensing electrode is composed of a plurality of the common electrodes; a plurality of sensing electrodes are routed between the data line and the first substrate, and each sensing The electrode trace is connected to a sensing electrode; wherein the positions of the plurality of sensing electrode traces are set according to positions corresponding to the plurality of data lines. The planar switching liquid crystal display device of claim 1, wherein the width of the plurality of sensing electrode traces is slightly smaller than the width of the plurality of data lines. The planar switching liquid crystal display device of claim 2, further comprising: at least one common line connected to the common electrode, wherein a common line in each of the sensing electrodes is turned on, and in a different sensing electrode The shared line is non-conducting. The planar switching liquid crystal display device of claim 3, wherein the common electrode and the pixel electrode are formed in a straight line or a zigzag shape. The planar switching liquid crystal display device of claim 4, further comprising: a liquid crystal layer disposed between the first substrate and a second substrate. The planar switching liquid crystal display device of claim 5, further comprising red, green and blue color filter layers respectively disposed on the red, green and blue sub-pixels of the second substrate. The planar switching liquid crystal display device of claim 6, further comprising: at least one black matrix disposed at a boundary between the sub-pixels and the thin film transistor. The planar switching liquid crystal display device of claim 7, further comprising: a driving circuit for providing at least one pixel voltage level for the common electrode and the pixel electrode in the sub-pixel A horizontal electric field is generated between them. The planar switching liquid crystal display device of claim 8, wherein the plurality of sensing electrode traces are made of a conductive metal material or an alloy material. The planar switching liquid crystal display device of claim 9, wherein the conductive metal material is one of the following: chromium, bismuth, aluminum, copper. The planar switching liquid crystal display device of claim 10, wherein the plurality of pixel electrodes, the plurality of common electrodes, and the common line are made of a transparent conductive material. The planar switching liquid crystal display device of claim 11, wherein the transparent conductive material is conductive indium tin oxide (ITO). The planar switching liquid crystal display device of claim 11, wherein each of the plurality of sensing electrodes comprises 3n×m sub-pixels, wherein n and m are natural numbers.