KR100935503B1 - Touch panel - Google Patents

Abstract

PURPOSE: A touch panel using an optical transmission substrate is provided to prevent the deterioration of transmittance by supplying a single substrate by supplying single substrate on the optical transmission substrate. CONSTITUTION: A substrate is formed with the optical transmissive material. A touch cell(60) includes a conducting pad(50) and a switching device of a three-terminal type(40). A touch unit approaches about the conducting pad from the non contact state. A touch position detector acquires the coordinate signal of corresponding touch cell about electrical signal.

Description

Touch panel {Touch panel}

The present invention relates to a touch panel, and more particularly, to generate a touch signal by detecting a non-contact or approach of a touch means including a touch pen that generates an electrical signal without bending the substrate, and to recognize a multi-touch point. The present invention relates to a touch panel having a new structure that can be provided as a single substrate and installed in a display device.

In general, the touch panel is attached to a display device such as a liquid crystal display (LCD), a plasma display panel (PDP), an organic light emitting diode (OLED), an active matrix organic light emitting diode (AMOLED), and a finger or a touch pen. It is one of the input devices for generating a signal corresponding to the corresponding position when an object such as the back contact. Touch panels are used in a wide range of fields, such as small portable terminals, industrial terminals, and digital information devices (DIDs).

Conventional touch panels have been disclosed in various types, but a resistive touch panel having a simple manufacturing process and a low manufacturing cost is most widely used.

1 shows an example of a resistive touch panel. Referring to FIG. 1, a first substrate 3 and a second substrate 5 are disposed to face each other on an upper surface of the display device 1, and an upper surface of the first substrate 3 and a lower surface of the second substrate 5. In each case, a transparent conductor such as indium tin oxide (ITO) is coated to form the conductive layers 7 and 9. A plurality of resistance points 11 are formed on the upper portion of the first substrate 3, and resistance points are formed on the lower portion of the second substrate 5, although not shown.

As illustrated, when an object such as the touch pen 17 contacts the second substrate 5, bending occurs on the second substrate 5 while the conductive layer 9 on the bottom surface of the second substrate 5 is removed. 1 is in contact with the conductive layer 7 on the upper surface of the substrate 3. At this time, the voltage applied to the conductive layers 7 and 9 drops due to the resistance obtained at the corresponding resistance point 11, and the detected voltage is converted into a digital signal through the AD converter 13 due to the change in the resistance value. The converted signal is transmitted to the CPU 15 to obtain the coordinate value of the point where the touch is made. Such a resistive touch panel is the most widely used touch panel because of its simple manufacturing process and low cost.

However, since the resistive touch panel detects a touch by using the bending of the second substrate 5, deformation of the second substrate 5 is inevitable, and many problems are exposed. For example, when the film is used as the second substrate 5, there is a problem that the display quality or durability is lowered due to the occurrence of scratches on the surface of the film. As another example, when glass is used as the second substrate 5, the glass is ground or etched to a thickness of 0.2 to 0.3 mm in order to give flexibility, which causes structural weakness and cracks when used for a long time. The problem of shortening the lifespan occurs.

In addition, the method of recognizing the touch by using the bending of the substrate 5 may not recognize the touch point when the bending of the second substrate 5 is low because the touch pressure is low, and sometimes the touch signal is lost. have.

Another problem of the resistance method is that two substrates 3 and 5 are used, and ITO or the like is applied over the entire area of each substrate 3 and 5. When two substrates 3 and 5 are used in this way and a multi-layer ITO is applied, the transmittance of the touch panel is lowered, which causes the display quality of the display device to be lowered. In addition, as the two substrates 3 and 5 are used, it is inevitable to install spacers for separating the substrates 3 and 5, which complicates the process and increases the process cost and lowers the yield.

Furthermore, the conventional touch panel has a problem in that it cannot recognize a multi-touch in which a plurality of points are simultaneously touched on the panel. For example, when a user touches with two fingers, or when a multi-touch occurs, such as when writing a multi-party writing on the copyboard at the same time, there is a problem that the multi-touch is not recognized or the touch panel malfunctions.

In addition, the conventional resistive touch panel requires an expensive AD converter 13 as a touch is sensed as an analog signal, time delay occurs in the signal processing, and zero adjustment is required for the resistance points. And the large display device 1 have various problems, such as being difficult to apply.

The present invention is proposed to solve the problems of the conventional touch panel as described above, a touch pen using a three-terminal switching element and a conductive pad on a single substrate to form a touch cell, and generates an electrical signal touch pen or similar characteristics By detecting the non-contact or approach of the touch means having a touch to enable the recognition of the touch signal for the multi-touch point, ultimately to prevent the shortening of the life due to scratches or bends applied to the substrate, improve the transmittance of the touch panel display When combined with the device, the display quality is improved, and the touch panel is easily built in the display device, and the manufacturing process of the display device that has been proven in mass production and product reliability can be used. The purpose is to provide a mass-produced touch panel.

In addition, the present invention, when the touch panel of the present invention is installed on the upper surface of the display device, in order to prevent the moiré phenomenon in which the wavy pattern appears due to the interference between the signal lines of the display device and the signal lines of the touch panel, the substrate Another purpose is to prevent the moiré phenomenon by installing a diffusion sheet at a lower portion of the touch panel or by arranging signal lines of the touch panel in an oblique direction with respect to the signal lines of the display device.

In addition, the present invention has another object to prevent the loss of the signal by storing the detected touch signal in the memory means so that when the touch signal is missing because a large amount of signal processing, by calling the signal stored in the memory.

The touch panel of the present invention for achieving the above object, in the touch panel for detecting the touch input of the touch means 35 for generating a predetermined electrical signal to generate a coordinate signal corresponding to the position, as a light transmissive material A configured substrate 30; A plurality of data signal lines 32 and gate signal lines 34 disposed on one surface of the substrate 30; A plurality of active regions in which touch is formed on the substrate 30, and are formed between the conductive pads 50, the conductive pads 50, and the data signal lines 32 in each of the divided regions. A touch cell 60 having a three-terminal switching element 40 to which a gate terminal is connected to a signal line 34; And a gate signal applied to the gate signal line 34 to control the switching element 40 of each touch cell 60 on / off, and the touch means 35 is in a non-contact state with respect to the conductive pad 50. When approaching, the electrical signal applied to the conductive pad 50 by the touch means 35 is obtained as the data signal line 32 in accordance with the on / off state of the switching element 40, thereby And a touch position detector 70 for acquiring a coordinate signal.

According to a preferred embodiment, the touch position detector 70 sequentially applies a scan pulse to each of the gate signal lines 34.

According to a preferred embodiment, the touch means 35 generates an electrical signal having a predetermined voltage level.

According to a preferred embodiment, the conductive pad 50 is installed only in the local region of the touch cell 60.

According to a preferred embodiment, the conductive pad 50 overlaps the upper surface of the data signal line 32 or the gate signal line 34 of the touch cell 60.

According to a preferred embodiment, the diffusion sheet 90 is further provided below the substrate 30.

According to a preferred embodiment, the data signal line 32 and the gate signal line 34 are arranged diagonally with respect to the signal line for screen display of the display device.

According to a preferred embodiment, the touch position detection unit 70 further includes a memory means 74 having addresses corresponding to the coordinate values of the touch cell 60, wherein the position detection signal is received from the data signal line 32. When the coordinate value of the corresponding touch cell 60 is stored in the corresponding address of the memory means 74.

According to a preferred embodiment, a plurality of auxiliary signal lines 36 are further disposed on one surface of the substrate 30, and each touch cell 60 is connected between the conductive pad 50 and the auxiliary signal lines 36. It further includes a capacitor 55.

According to a more preferred embodiment, a transparent insulating film for protecting the touch cell 60 is coated on one surface of the substrate 30.

According to the touch panel of the present invention, a touch cell including signal lines, a conductive pad, and a three-terminal switching element connected thereto are formed in each partitioned area by wiring signal lines on a single substrate and partitioning an active area where a touch is made. When a touch pen for applying an electrical signal or a touch means having similar characteristics approaches the conductive pad in a non-contact manner, a voltage is formed on the conductive pad and the coordinate signal of the touch cell is acquired according to the change of state of the switching element. Since the touch signal can be generated without bending the substrate during the touch input, the pressure applied to the substrate is small so that the signal is not dropped and the life of the substrate can be expected to be longer than that of the touch panel using the bending of the substrate. Transmittance is greatly improved by using a single substrate, which greatly increases the display quality of the display device. It does not deteriorate, and components such as spacers for separation of the substrate are not necessary, so that the panel can be manufactured more slim, and it is easy to assemble the built-in display device, and in each touch cell using a 3-terminal switching element such as TFT Acquired signals are independently recognized to enable multi-touch recognition, and by using the manufacturing process of TFT substrates verified by LCD or AMOLED, it is possible to secure very high mass productivity and product reliability. By applying and processing digital signals, no additional process of converting signals is required, and the response speed is very fast, and it can prevent malfunction due to noise or other external environmental factors, and it can be used under sunlight, and zero adjustment, etc. This is unnecessary and has an effect suitable for use in a large display device.

In addition, according to the present invention, when the touch panel of the present invention is installed on the upper surface of the display device by installing a diffusion sheet in the lower portion of the substrate or by arranging signal lines of the substrate in a diagonal direction with respect to the signal line of the display device, There is an effect that can prevent the moiré phenomenon that the appearance of the wave pattern.

Further, according to the present invention, when the position detection signal is temporarily stored in the memory means, and the amount of signal processing in the touch position detection unit is not recognized, the position detection signal received in real time may be called and processed by calling the signal stored in the memory means. Therefore, there is an effect that can prevent the loss of the signal.

In addition, according to the present invention, by allowing the non-contact touch between the touch means and the conductive pad can be recognized, the conductive pad can be protected by a protective coating layer or the like, or installed on the lower surface of the substrate to conceal the transparent pad. It prevents the phenomenon of losing and makes life expectancy longer.

Furthermore, since the control ICs used in the present invention do not drive a load but only transmit / receive signals unlike a source IC of a display device such as an LCD or an AD converter used in a conventional touch panel, the control ICs consume power for driving the IC itself. Power can be minimized. In particular, the receiving control IC receives the signal with high impedance (Hi-impedance), so there is little current consumption. A portable terminal such as a cellular phone is an important factor to improve portability, and it is required to minimize current consumption. When the touch panel of the present invention is applied to a portable terminal, the use of a battery can be extended more than other touch panels. Have

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings and embodiments.

First, the present invention relates to a touch panel that is installed in addition to the upper surface of a display device such as LCD, PDP, OLED, AMOLED or the like, or is used alone. Unlike the method of acquiring a touch signal when two substrates abut, a touch cell formed of a 3-terminal switching element such as a thin film transistor (TFT) and a conductive pad is formed on a single substrate to apply an electrical signal. When a touch means such as a pen approaches a conductive pad in a non-contact manner to form a predetermined voltage on the conductive pad, the present invention relates to a touch panel that senses a change in electrical state of the conductive pad and acquires a touch signal.

The touch panel according to the present invention basically divides a single substrate into a plurality of regions, and in each of the divided regions, a three-terminal switching element and a conductive pad are installed to form a unit touch cell. The input terminal and the output terminal of the switching element are connected to the conductive pad and the data signal line, respectively, and the gate signal line is connected to the on / off control terminal (or gate terminal) of the switching element. The touch position detector turns on / off the switching element by applying an on / off control signal through the gate signal line. When a predetermined voltage is applied to the conductive pad by touch means such as a touch pen, the state of the switching element is changed according to the voltage applied to the on / off control terminal of the switching element, and the voltage of the conductive pad is output through the data signal line. . The touch position detector obtains a touch signal by receiving a voltage of the data signal line, that is, a position detection signal.

Although not described in this embodiment, the position detection signal is transmitted and received using a data signal line and a gate signal line, and each touch cell is provided with a switching element and a conductive pad to change the state of the switching element when an electrical signal is applied to the conductive pad. Embodiments of obtaining a touch signal by means of the present invention will be included.

Further, although the touch panel of the present invention is provided separately from the display device, like the display panel such as LCD or AMOLED, the signal lines are wired on the substrate and the TFT is disposed in the unit touch cell (the unit pixel in the LCD). It can be manufactured by borrowing the manufacturing process of the TFT substrate which has already been verified product reliability and mass production. Therefore, more stable manufacturing process and product reliability can be expected. Of course, the display panel and the touch panel of the display device are similar in appearance but actual functions and operations are different.

In the embodiments described below, the switching element can be described as being replaced by "TFT", and the same reference numerals are used for the switching element and the TFT. In addition, the touch means may also be replaced with a "touch pen", and the same reference numerals are used for the touch means and the touch pen.

Figure 2 is an exploded perspective view showing the structure of a touch panel according to the present invention, schematically showing the basic structure of the touch panel of the present invention. As illustrated, a touch panel of a single substrate 30 is installed on the upper surface of the display device 20, and a touch means 35 such as a touch pen contacts the surface of the substrate 30 to provide a position detection signal to the touch panel. To pass. The substrate 30 is made of a light transmissive material such as glass, plastic, or film. As shown in the drawing, a receiving / receiving control IC 71 for receiving a position detection signal of a data signal line or applying a gate signal is mounted at an edge portion of the substrate 30. The receiving / receiving control IC 71 may be distributed and installed at the edge portion of the substrate 30, or may be integrated and installed at one edge portion of the substrate. In addition, the receiving / receiving control IC 71 may be mounted in the form of a chip on film (COF) or a chip on glass (COG) at an edge portion of the substrate 30. .

Although FIG. 2 illustrates that the touch panel of the present invention is stacked on the display device 20, the touch panel of the present invention may be manufactured to be very slim because the touch panel of the present invention is composed of a single substrate 30. Even if the inside of the display device 20 is incorporated, the light and small size of the display device is not significantly impaired. This is one of the important technical advantages of the present invention. For example, in the case of LCD, a touch panel and a polarizing plate composed of a single substrate 30 of the present invention are laminated on an LCD panel on which a TFT substrate and a color filter substrate are bonded, and then these are installed in a housing of a BLU. The panel may be embedded in the display device 20.

3 is a diagram illustrating an example in which a touch cell 60 is formed on a substrate 30, FIG. 4 is a diagram illustrating a configuration example of a unit touch cell, and FIG. 5 is a cross-sectional structure of the touch cell illustrated in FIG. 4. It is a cross section shown. The configuration of the present invention will be described in more detail with reference to these three drawings.

3 and 4, a plurality of data signal lines 32 and gate signal lines 34 are disposed on one side of the substrate 30. The data signal line 32 is a line for transmitting the position detection signal, and the gate signal line 34 is a line for controlling on / off of the switching element. In the illustrated embodiment, the data signal line 32 and the gate signal line 34 are cross-wired. However, this is merely shown to help understanding of the present invention, and the data signal line 32 and the gate signal line 34 It may be wired side by side, or may be wired in a diagonal form.

As shown, a three-terminal switching element 40 is provided between the data signal line 32 and the conductive pad 50, and the gate signal line 34 is provided on the on / off control terminal 44 of the three-terminal switching element. This connection is made to form the touch cell 60.

The three-terminal switching element 40 is preferably TFT. The three-terminal switching element 40 is to control the opening and closing of the switch by using a signal applied to the on / off control terminal is that it can stably block the flow of the signal and the interference between the signals.

 As shown, the input terminal of the TFT 40 is connected to the conductive pad 50 and the output terminal is connected to the data signal line 32. Therefore, when the OFF voltage is applied to the gate terminal 44 which is the on / off control terminal, the TFT 40 cuts off the connection between the data signal line 32 and the conductive pad 50 and turns on the gate terminal. On) is applied when the voltage is applied to receive the position detection signal applied to the conductive pad 50 through the data signal line (32).

Referring to FIG. 5, the TFT 40 includes a gate terminal 44 connected to the gate signal line 34, a source terminal 42 which is an input terminal of the TFT connected to the conductive pad 50, and a data signal line 32. A drain terminal 43 which is an output terminal of the TFT connected with the drain terminal 43; An active layer 48 overlapping the gate terminal 44 and forming a channel between the source terminal 42 and the drain terminal 43 is provided. The active layer 48 is formed such that the source terminal 42 and the drain terminal 43 overlap each other. An ohmic contact layer 49 for ohmic contact between the source terminal 42 and the drain terminal 43 is further formed on the active layer 48. The active layer 48 is formed of amorphous silicon (A-si) or polysilicon (P-Si).

A gate insulating layer 46 is disposed on the upper surface of the gate terminal 44, and a passivation layer 47 is disposed on the source terminal 42 and the drain terminal 43. The conductive pad may be formed of a transparent conductive material such as indium tin oxide (ITO), indium zion oxide (IZO), antimony tin oxide (ATO), or carbon nanotube. A contact hole 45 using ITO or the like is used to connect the conductive pad 50 and the source terminal 42 of the TFT 40. In addition, a layer for blocking light may be provided on an upper surface of the TFT 40, and a metal or gate terminal used for manufacturing the source terminal 42 or the drain terminal 43 of the TFT 40 may be provided. 43) The metal used in the manufacture can be used. This is to prevent the TFT 40 from malfunctioning in response to light.

On the other hand, when the touch pen 35 capable of applying the above-mentioned electrical signal, i.e., a predetermined voltage of -Vs, contacts the substrate 30 or the transparent insulating layer 65, the conductive pad 50 in the touch cell 60 is touched. ) And a touch pen are formed based on the dielectric constant of the material formed between them and a voltage of Vs is formed on the conductive pad 50. It is used as a position detection signal and is transmitted to the data signal line 32 according to the state of the switching element.

Meanwhile, referring to FIG. 4, the conductive pad 50 may be installed to cover the entire area of the touch cell 60, but is preferably installed only in the local area of the touch cell 60. For example, an end portion of the touch pen contacting the outer surface of the substrate 30 or the transparent insulating layer 65 has a width of 0.5 mm or less in width and length, respectively. When the width of each touch cell 60 is smaller than this, The conductive pad 50 may be in contact with a portion of the touch pen even when the conductive pad 50 is formed to cover only a local area of the touch cell 60.

More preferably, as in the case of FIG. 6, the conductive pad 50 is formed to overlap one of the signal lines 32 and 34. Thus, by forming the area of the conductive pad 50 so as to be local to the touch cell or to overlap the signal lines 32 and 34, the transmittance of the touch panel will be greatly improved.

The touch cell 60 is formed by dividing an active area on which a touch is actually made on the panel. In the display device 20 such as an LCD, the unit pixels are arranged in a matrix like the unit pixels are arranged in a matrix. In addition, the touch panel of the present invention is proportional to the size of the display device 20, and it is preferable that the touch cell 60 is designed with a resolution reduced to an integer ratio rather than the resolution of unit pixels of the display device 20 as much as possible. . This is because, in order for the touch panel of the present invention to acquire a touch signal stably, the size of the conductive pad 50 is preferably larger than the unit pixel of the display device 20. Of course, the touch cell 60 may be configured to have the same resolution or enlarged resolution as the unit pixel of the display device 20.

As such, when the resolution of the touch cell 60 is reduced to the same resolution as the unit pixel of the display device 20 or at an integer ratio, the data signal line 32 and the gate signal line 34 of the touch panel are changed to the gate line and data of the LCD. It can be positioned on the same vertical line as the line, which improves the display quality of the display device 20 by increasing the transmittance of the touch panel, and a wave pattern appears due to interference between signal lines of the display device 20 and signal lines of the touch panel. Moiré phenomenon can be prevented.

On the other hand, the embodiment shown in Figures 7 and 8 provides another method for preventing the moiré phenomenon. Referring to FIG. 7, a diffusion sheet 90 may be further installed below the substrate 30. When the diffusion sheet 90 is disposed below the substrate 30, the diffusion sheet 90 is positioned between the display device 20 and the touch panel, and the signal line wiring of the display device 20 and the signal line of the touch panel are disposed. The moiré phenomenon can be prevented by the diffusion effect of the diffusion sheet 90 even if the wirings are not located vertically on the same line.

Meanwhile, referring to still another example of FIG. 8, the wirings added by dotted lines in vertical and horizontal lines are signal lines of the display device, and in the case of the LCD display device, the gate signal lines in the lateral direction and the source signal lines in the vertical direction. The data signal line 32 and the gate signal line 34 of the substrate 30 are disposed at a predetermined angle with respect to the signal line of the display device 20, which is the signal lines of the display device 20 and the signal lines of the substrate 30. Since there is no wiring in the same direction, the moiré phenomenon caused by optical interference between signal lines in the same direction can be prevented. If the signal lines of the display device 20 are arranged diagonally, the signal lines of the substrate 30 may be arranged in a straight line.

Referring back to FIG. 3, it can be seen that the touch cell 60 is shown at a resolution of 3 × 3. Although the touch cell 60 is actually arranged at a very high resolution, the touch cell 60 is shown in FIG. 3 with a resolution of 3 × 3. Embodiments to be described later will be described by illustrating that the touch cells 60 are arranged at a resolution of 3 × 3.

9 is a block diagram illustrating a system configuration of the present invention. Referring to this, the touch position detector 70 is installed at one side or the outside of the touch panel. As shown, the touch position detecting unit 70 is composed of a receiving and receiving control IC 71, a timing control unit 72, a signal processing unit 73, and a memory means 74, the power supply terminal 75 is added Can be. The power supply terminal 75 generates a power lamp applied to the gate signal line. The touch signal acquired by the touch position detector 70 is transmitted to the CPU 80 to generate an input signal corresponding to the coordinate.

The receiving / receiving control IC 71 applies a signal SWn for the on / off signal of the switching element 40 to the gate signal line 34 and receives the position detection signal Sn from the data signal line 32. . As mentioned above, the receiving / receiving control IC 71 is mounted on one side edge portion of the substrate 30 in the form of COG or COF.

Preferably, the receiving / receiving control IC 71 sequentially applies the scan pulse SWn to each of the gate signal lines 34. To this end, the timing controller 72 generates a time division signal of several tens of ms or less, for example, and the signal processor 73 controls the reception and reception of a waveform as shown in FIG. 10 according to a clock provided from the timing controller 72. It is provided to the IC 71 side.

The low voltage applied to the gate signal line 34 is sufficient to turn off the TFT 40. In one embodiment, -5 to -10V is used. The high voltage is a voltage sufficient to turn on the TFT 40, and in one embodiment, 12 to 18V is used.

Referring to the waveform diagram of FIG. 10, the time division scan pulses of SW1, SW2, and SW3 are applied to each gate signal line 34 by the reception / reception control IC 71. The period of each pulse is “T”, and there may be a pause between each pulse to stabilize the signal.

In FIG. 3, when the touch pen 35 having a voltage of -5V is in contact with or close to the surface of the substrate 30 or the transparent insulating layer 65 including the touch cell 60 at the lower right, the touch is performed. A capacitor is formed between the pen 35 and the conductive pad 50, and a voltage of 5 V is formed on the conductive pad 50. This is a method of applying a voltage in a non-contact manner since the touch pen 35 does not directly contact the conductive pad.

Accordingly, the position detection signal Sn is obtained from the data signal line 32 connected to the touch cell 60 at the timing when the scan pulse is applied to the gate signal line 34. Referring to the waveform diagram of FIG. 10, the S3 position detection signal may be obtained through the rightmost data signal line 32 at the times t3 to t4. The detected signal is transmitted to the signal processor 73, and the touch position detector 70 obtains a touch signal corresponding to the corresponding coordinate values “SW3, S3”. That is, when the SW3 scan signal is generated, if the S3 signal is obtained, this means that the touch is made at the "SW3, S3" coordinates.

However, in the process of processing a large number of signals, when the CPU 80 is in the "Busy" state, a case where the position detection signal may not be recognized. Since a touch signal that is not already recognized cannot be reproduced, this may result in the loss of the signal, leading to a decrease in reliability of the touch panel.

In order to prevent this, the touch position detector 70 includes a memory means 74 having a bit or more than the number of touch cells 60. Preferably, the memory means 74 has an absolute address corresponding to the coordinate value of the touch cell 60, as shown in FIG. In this embodiment, the memory means 74 has a capacity of at least 9 bits, and the position detection signal received by the touch position detection unit 70 is stored at the address "m9" as coordinate values "SW3, S3". The signals thus stored may be called and used by the signal processor 73. For example, the touch position detector 70 may scan the entire signal applied to the gate signal line 34 once, and then read the memory means 74 to check whether there is a missing signal. If the resolution of the touch cell 60 is 1366x768, the memory means 74 needs a capacity of at least 1049088 bits or more and secures a capacity of about 132k bytes.

On the other hand, in the basic embodiment as shown in FIG. 3, although an electrical signal is applied by the touch means 35 to the touch cell 60 connected to the gate signal line 34 to which the scan pulse is not yet applied, the detection thereof is detected. If the duration of the electrical signal applied by the touch means 35 is insufficient or disappears at the time when the scan pulse of the corresponding gate signal line 34 is applied, the touch position cannot be detected, resulting in deterioration of the reliability of the touch panel. Will come.

12 is an embodiment for solving this problem, and an auxiliary signal line 36 is added to one side of the substrate 30 and a capacitor is added between the conductive pad 50 and the auxiliary signal line 36. In this embodiment, the auxiliary signal line 36 is added in the transverse direction of the substrate, and may be disposed in the longitudinal direction.

The signal AUXn applied to the auxiliary signal line 36 is, in one embodiment, a ground having a zero potential, and may be connected to the receiving / receiving control IC 71 and outside the receiving / receiving control IC 71. May be authorized.

The voltage generated in the conductive pad 50 by the touch means 35 is charged in the capacitor 55 and is output to the day line signal line 32 at the time when the TFT 40 is turned on by applying a scan pulse to the touch position. Touch position detection is possible without omission.

In the present invention, since an electrical signal is applied using a capacitor formed between the touch means 35 and the conductive pad 50, the touch means 35 may apply a touch position in a non-contact manner to the conductive pad 50. Can be. Providing such a touchless touch provides a very technical advantage. That is, the touch cell 60 including the conductive pad 50 may be coated with a transparent insulating film such as a film, a plastic or an organic insulating film, or a transparent adhesive. In addition, since the conductive pad 50 is designed to be positioned on the rear surface of the substrate 30, the coating layer may not be formed on the upper surface of the touch cell 60. Therefore, it is possible to prevent an increase in the process cost for the protection of the conductive pad 50, and to position the conductive pad 50 more safely, thereby improving durability and expecting longer life.

In the touch panel of the present invention as described above, a signal line is vertically and horizontally disposed on one substrate, and the touch position is contacted by a touch means such as a pen which applies a voltage by forming a touch cell using a conductive pad and a TFT. To detect. The biggest technical advantage of the present invention is that the multi-touch can be recognized by excluding interference of touch position detection signals generated in the data signal line by the switching action of the TFT.

In addition, the end of the touch pen is narrowed and the size of the corresponding touch cell is reduced to enable writing of high resolution.

In addition, when detecting the touch position, it is possible to use the digital signal because the touch input is discriminated by the presence or absence of the signal, not the magnitude of the signal. No adjustment is required, and the conductive pad can be installed only in the local area of the touch cell to improve the transmittance.

Furthermore, the touch panel of the present invention can secure mass production and greatly reduce manufacturing cost by using a TFT substrate manufacturing process such as an LCD without changing equipment. In addition, the manufacturing process of LCD has already secured high technology and reliability, it can bring it as it is.

In addition, the technical advantage of the present invention is to prevent the moiré phenomenon caused by the interference of the signal line of the display device 20 and the signal line of the touch panel, which is added to the diffusion sheet 90 between the display device 20 and the touch panel. Alternatively, the signal line of the touch panel may be disposed to have a predetermined angle with the signal line of the display device.

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and various substitutions, modifications, and changes are possible in the technical field of the present invention without departing from the technical spirit of the present invention. It will be clear to those of ordinary knowledge.

1 is a cross-sectional configuration view showing a conventional resistive touch panel

2 is an exploded perspective view showing the structure of a touch panel according to the present invention;

3 is a configuration diagram showing an example in which a touch cell is formed on a substrate

4 is a diagram illustrating a configuration example of a unit touch cell;

5 is a cross-sectional view showing the structure of a touch cell according to the present invention;

6 illustrates an example in which a conductive pad is formed.

Figure 7 is an exploded perspective view showing an example of the diffusion sheet is installed

8 is a block diagram of a signal line for removing moiré

9 is a block diagram illustrating a system configuration of the present invention.

10 is a waveform diagram illustrating pulses transmitted and received on a signal line;
11 is a block diagram schematically showing a memory means of the present invention;

12 is a block diagram showing another embodiment of the present invention with a capacitor added

<Explanation of symbols for the main parts of the drawings>

20 display device 30 substrate

32: data signal line 34: gate signal line

35: touch means 36: auxiliary signal line

40: switching element (TFT) 42: input terminal (source terminal)

43: Output terminal (drain terminal) 44: On / off control terminal (gate terminal)

45 contact hole 46 gate insulating film

47: protective film 48: active layer

49: ohmic contact layer 50: conductive pad

55 capacitor 60 touch cell

65: transparent insulation layer 70: touch position detection unit

71: reception and reception control IC 72: timing control unit

73: signal processor 74: memory means

75: power stage 80: CPU

90: diffusion sheet

Claims (10)

In the touch panel for detecting a touch input of the touch means 35 for generating a predetermined electrical signal to generate a coordinate signal corresponding to the corresponding position, A substrate 30 made of a light transmissive material; A plurality of data signal lines 32 and gate signal lines 34 disposed on one surface of the substrate 30; A plurality of active regions in which touch is formed on the substrate 30, and are formed between the conductive pads 50, the conductive pads 50, and the data signal lines 32 in each of the divided regions. A touch cell 60 having a three-terminal switching element 40 to which a gate terminal is connected to a signal line 34; And The gate signal is applied to the gate signal line 34 to control the switching element 40 of each touch cell 60 on / off, and the touch means 35 approaches the conductive pad 50 in a non-contact state. In this case, the electrical signal applied to the conductive pad 50 by the touch means 35 is obtained as the data signal line 32 according to the on / off state of the switching element 40, and the coordinate of the corresponding touch cell 60 is obtained. And a touch position detector (70) for acquiring a signal. The method of claim 1, The touch position detector (70) is characterized in that to sequentially apply the scan pulse to each of the gate signal line (34). The method of claim 1, The touch means (35) is a touch panel, characterized in that for generating an electrical signal having a predetermined voltage level. The method of claim 1, The conductive pad 50 is installed only in the local area of the touch cell 60. The method of claim 1, The conductive pad 50 is disposed overlapping the upper surface of the data signal line 32 or the gate signal line 34. The method of claim 1, The touch panel, characterized in that the diffusion sheet 90 is further provided below the substrate (30). The method of claim 1, And the data signal line (32) and the gate signal line (34) are arranged in an oblique direction with respect to the signal line for screen display of the display device. The method of claim 1, The touch position detector 70 further includes a memory means 74 having addresses corresponding to the coordinate values of the touch cell 60, and when the position detection signal is received from the data signal line 32, the corresponding touch cell 60. The coordinate value of) is stored in the corresponding address of the memory means (74). The method of claim 1, A plurality of auxiliary signal lines 36 are further disposed on one surface of the substrate 30, and each touch cell 60 further includes a capacitor 54 connected between the conductive pad 50 and the auxiliary signal line 36. Touch panel comprising a. The method of claim 1, One surface of the substrate 30 is a touch panel, characterized in that the transparent insulating film for protecting the touch cell (60) is coated.

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