KR20140148363A - Touch detecting means, method and touch screen panel using driving back, and display device embedding said the touch screen panel - Google Patents

Abstract

The present invention relates to an apparatus and a method for detecting a touch through a novel method of detecting a driving back phenomenon from a touch pad through a driving voltage applied through a driving capacitor to detect a touch signal, a touch screen panel, and a display apparatus having the touch screen panel. The apparatus for detecting the touch according to the present invention is provided on a top surface of the display device and detects the occurrence of a touch capacitance (Ct) by the approach of a touch input unit, such as a bodily finger (25) or a touch input unit such as a conductor similar to the bodily finger, and comprises a touch pad (10) that forms the touch capacitance (Ct) between the touch input unit and the touch pad; a driving capacitor (Cdrv) having one side connected to the touch pad (10) and the other side applied with driving voltage for touch detection; a detector that detects a common voltage generated from the display device; a driving voltage generator that generates the driving voltage in synchronization with the common voltage; and a touch detector (14) connected with the touch pad (10) to detect a touch signal using the driving back phenomenon when the touch capacitance (Ct) is applied to the driving capacitor (Cdrv) according to the touch state of the touch input unit.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a touch sensing device, a sensing method, and a touch screen panel using a driving back phenomenon, and a display device incorporating such a touch screen panel,

The present invention relates to a means, a method and an apparatus for detecting a touch input of a touch input means having a finger or a similar conductive characteristic of a body, and more particularly, A touch detection method and a touch screen panel for acquiring a touch signal by using a driving back phenomenon generated in a touch detection unit, and a display device incorporating such a touch screen panel.

Generally, a touch screen 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), or an active matrix organic light emitting diode (AMOLED) And is an input device that generates a signal corresponding to a position when an object such as a finger or a pen is touched. The touch screen panel is used in a wide range of fields such as a small portable terminal, an industrial terminal, and a DID (Digital Information Device).

Conventionally, various types of touch screen panels have been disclosed, but resistance type touch screen panels having a simple manufacturing process and a low manufacturing cost have been widely used. However, since the resistance type touch screen panel has low transmittance and must be applied with pressure, it is inconvenient to use, and it is difficult to recognize multi-touch and gesture, and detection error occurs.

On the other hand, capacitive touch screen panels are increasingly penetrating the market because of their high transmittance, soft touch recognition, and good multi-touch and gesture recognition.

1 shows an example of a conventional capacitive touch screen panel. 1, a transparent conductive film is formed on the upper and lower surfaces of a transparent substrate 2 made of plastic or glass, and metal electrodes 4 for voltage application are formed on each of four corners of the transparent substrate 2. The transparent conductive film is formed of a transparent metal such as ITO (Indium Tin Oxide) or ATO (Antimony Tin Oxide). The metal electrodes 4 formed at the four corners of the transparent conductive film are formed by printing with a conductive metal having a low resistivity such as silver (Ag). A resistor network is formed around the metal electrodes 4. The resistance network is formed with a linearization pattern for uniformly transmitting a control signal to the entire surface of the transparent conductive film. A protective film is coated on the transparent conductive film including the metal electrode 4.

When a high frequency AC voltage is applied to the metal electrode 4, the electrostatic touch screen panel is spread over the front surface of the transparent substrate 2. At this time, if the transparent conductive film on the upper surface of the transparent substrate 2 is lightly touched by the finger 8 or the conductive touch inputting means, a certain amount of current is absorbed into the body and the current sensor incorporated in the controller 6 senses the change of current, The touch points are recognized by calculating the amount of current in each of the metal electrodes 4.

However, since the electrostatic touch screen panel as shown in FIG. 1 is a method of detecting the magnitude of the minute current, an expensive sensing device is required, so that the price rises and multi-touch which recognizes a plurality of touches is difficult.

In order to overcome such a problem, a capacitive touch screen panel as shown in FIG. 2 has been used in recent years. The touch screen panel of FIG. 2 includes a horizontal linear touch pad 5a and a longitudinal linear touch pad 5b, and a touch drive IC 7 for analyzing a touch signal. This touch screen panel detects the magnitude of the capacitance formed between the linear touch pad 5 and the finger 8. The horizontal linear touch pad 5a and the longitudinal linear touch pad 5b are scanned So that a plurality of touch points can be recognized.

However, when the touch screen panel is mounted on a display device such as an LCD, it is difficult to detect a signal due to noise. For example, the common electrode of the LCD is used, and the AC common voltage Vcom is applied to the common electrode in some cases. The common voltage Vcom of the common electrode acts as noise at the touch point detection.

Figure 3 shows an embodiment in which a conventional capacitive touch screen panel is mounted on an LCD. The display device 200 has a structure in which a liquid crystal is enclosed between the TFT substrate 205 on the lower side and the color filter 215 on the upper side to form the liquid crystal layer 210. The TFT substrate 205 and the color filter 215 are bonded to each other by the sealant 230 at the outer portion thereof. Although not shown, a polarizing plate is attached to the upper and lower sides of the liquid crystal panel, and a BLU (Back Light Unit) is installed thereon.

As shown in the figure, a touch screen panel is installed on the display device 200. The touch screen panel has a structure in which the linear touch pad 5 is mounted on the upper surface of the substrate 1. [ On the substrate 1, a protective panel 3 for protecting the linear touch pad 5 is attached. The touch screen panel is adhered to an edge portion of the display device 200 via an adhesive member 9 such as DAT (Double Adhesive Tape) or the like, and forms an air gap 9a with the display device 200.

In such a configuration, when a touch as shown in FIG. 3 occurs, a capacitance (or a capacitance) such as Ct is formed between the finger 8 and the linear touch pad 5. As shown in the drawing, a capacitance such as Cvcom is formed between the linear touch pad 5 and the common electrode 220 formed on the lower surface of the color filter 215 of the display device 200, Cp, which is an unknown parasitic capacitance due to capacitance coupling or manufacturing process factors, is also operating. Therefore, a circuit similar to that of the equivalent circuit of Fig. 4 is constructed.

Here, the conventional touch screen panel detects a touch by detecting a change amount of Ct, and components such as Cvcom and Cp act as noise in detecting Ct. For example, since the common voltage Vcom of the common electrode 220 is used for one or a plurality of gate lines alternately in order to reduce current consumption in a small / medium-sized LCD for a portable device, It acts as a considerable noise in touch detection.

In order to remove such noise, an air gap 9a is placed between the touch screen panel and the display device 200 as shown in FIG. Although not shown, ITO or the like is coated on the lower surface of the touch screen panel 50 (1) to form a shielding layer, and this shielding layer is grounded to the ground signal.

However, the thickness of the product is increased by the air gap 9a, and quality deterioration occurs. Further, since a separate shielding layer and a manufacturing process are required to constitute a shielding layer, an increase in manufacturing cost is caused. In particular, when the touch screen panel is built in the LCD, it is impossible to manufacture the touch panel because the air gap 9a or the shielding layer can not be formed.

A driving voltage is applied to one side of the driving capacitor by connecting a driving capacitor to the touch detection unit. The driving voltage is applied between the touch input unit such as a hand and the touch pad When the touch capacitance is formed in the touch panel, a touch signal is obtained by using a driving back phenomenon in which the magnitude of the voltage detected by the touch detection unit varies according to the magnitude of the touch capacitance, Touch sensing means using a new type of driving back phenomenon that minimizes the influence of parasitic capacitance and stably acquires a touch signal and easily incorporates a touch screen function in a display device such as an LCD, Detecting method and touch screen panel, and a method of detecting such a touch screen panel To provide value markets that purpose.

According to an aspect of the present invention, there is provided a touch detection device for detecting touch capacitance Ct generated by approaching a touch input means such as a finger of a user's body or the like, The touch pad according to claim 1, further comprising: a touch pad forming a touch capacitance (Ct) with the touch input means; A driving capacitor Cdrv having one side connected to the touch pad and a driving voltage for touch detection applied to the other side; A touch detection unit connected to the touch pad and detecting a touch signal using a driving back phenomenon when the touch capacitance Ct is added to the driving capacitor Cdrv according to whether the touch input unit is touched or not, ; And a memory unit for storing the touch signal detected by the touch detecting unit, wherein the memory unit stores a plurality of touch signals for binding and storing touch signals of the touch pad in one of a horizontal direction and a vertical direction of the touch pad Line memory.

According to an embodiment, the touch detection means includes: a common voltage detection unit for detecting a common voltage generated in the display device; And a driving voltage generator for generating a driving voltage in synchronization with the common voltage.

According to another embodiment, when a set of touch pads is referred to as a frame, the memory unit includes a frame memory for storing a sensor signal of the touch pads and a detected voltage value in one frame.

According to another embodiment, the memory unit may be constituted by a non-volatile memory such as a flash memory or an E2PROM and a volatile memory such as an SRAM or a DRAM, and the non- One or more of the programs are stored.

According to another embodiment, a common electrode capacitance (Cvcom) is formed between the touch pad and the common electrode of the display device.

According to another embodiment, the driving voltage Cdrv is not connected to the common voltage detecting unit.

According to another embodiment, the touch pad is connected to the touch detection unit or the common voltage detection unit.

According to another embodiment, a charging means for applying a pre-charge voltage to the touch pad connected to the common voltage detecting portion is connected.

According to another embodiment, the charging means is a switching element, and the output portion of the switching element connected to the touch pad connected to the common voltage detecting portion at the time of the common voltage detection is in a high impedance state.

According to another embodiment, the charging means maintains the off state for a predetermined time, and the common voltage detecting portion detects the common voltage when the charging means is in an off state.

According to another embodiment, the charging means 12 of the common voltage detector 15 turns on / off in synchronization with the common voltage.

According to another embodiment, there is further provided a means for setting the charging time of the charging means.

According to another embodiment, the driving voltage is applied to one side of the driving capacitor Cdrv in synchronism with either the common voltage or the charging time.

According to another embodiment, the touch detection unit detects a touch signal after a predetermined time after the driving voltage is applied.

According to yet another embodiment, the input of the common voltage detector is in a high impedance state.

According to another embodiment, the signal output from the common voltage detector is input to a comparator to detect whether the common voltage is high (Hi) or low (Low).

According to another embodiment, either the upper reference voltage for detecting the Hi state of the common voltage or the lower reference voltage for detecting the Low state of the common voltage is input to the comparator.

According to another embodiment of the present invention, at least one or more touch pads of the touch pad contacting the common voltage detecting unit are sequentially used.

According to another embodiment, when the touch pad connected to the common voltage detecting unit is connected to the touch detecting unit, another touch pad not connected to the touch detecting unit is connected to the common voltage detecting unit to detect the common voltage.

According to another embodiment of the present invention, there is provided a means for causing the signal of the common voltage detecting portion to be outputted to the outside of the TDI (Touch Drive IC).

According to another embodiment of the present invention, there is further provided a means for determining whether to output the signal of the common voltage detector to the outside of the TDI.

According to another embodiment of the present invention, the voltage detected by the touch detecting unit 14 when the touch failure is generated is determined by Equation (1) below, and the voltage detected by the touch detecting unit when the touch capacitance Ct is added is The driving back is generated by the difference between Equation 1 and Equation 2. In Equation 2,

≪ Formula 1 >

&Quot; (2) "

는 터치검출부에서 검출된 전압이며,Vh는 드라이빙 커패시터에 인가되는 하이 레벨 전압이며, Vl은 드라이빙 커패시터에 인가되는 로우 레벨 전압이며, Cdrv는 드라이빙 커패시턴스이며, Cvcom은 공통전극커패시턴스이며, Cp는 기생커패시턴스이며, Ct는 터치커패시턴스임.)
(here,

Vh is a low level voltage applied to the driving capacitor, Cdrv is a driving capacitance, Cvcom is a common electrode capacitance, Cp is a parasitic capacitance And Ct is the touch capacitance.

According to another embodiment, the touch detection unit 14 detects the touch area of the touch input unit with respect to the touch pad 10 in accordance with the size of a driving back.

According to another embodiment, the sensor signal lines are located on the left and right sides of the touch pad.

According to another embodiment, the non-detecting touch pad connected to the touch detecting unit and excluding the touch pad detecting the touch is in the floating state.

According to another embodiment, the non-detecting touch pad has a floating state before the charging means of the touch detecting unit is turned on.

According to another embodiment, after the driving voltage is applied to the driving capacitor Cdrv connected to the touch detection unit, the touch pad connected to the touch detection unit is separated from the touch detection unit.

According to another embodiment, the touch pad connected to the touch detection unit is disconnected from the touch detection unit 14 within 1 ns to 100 us after the driving voltage is applied to the driving capacitor connected to the touch detection unit.

According to another embodiment, the touch pad separated from the touch detection unit is reconnected to the touch detection unit or a predetermined voltage is applied after the touch sensing unit completes touch sensing.

According to another embodiment, the predetermined voltage is a ground (GND) or a constant-sized DC voltage.

According to another embodiment, after the touch sensing operation of the touch detection unit is completed, ground or a DC voltage of a predetermined magnitude is applied to the floating touch non-detecting touch pad.

According to the touch detection means, the detection method, and the touch screen panel using the driving back phenomenon of the present invention and the display device incorporating such a touch screen panel, the common electrode of the display device can have a common voltage level Or when the common electrode of the display device is at the DC level or if the common electrode of the display device is alternated at an unspecified frequency where the common electrode is not specified, the state change of the common voltage is detected and the state change time point is avoided A drive voltage is applied through a driving capacitor connected to the touch detection unit, and detection of a driving back occurring in the touch detection unit by a touch capacitance added by a touch input is performed to acquire a touch signal, And other factors are minimized, and the influence of the parasitic capacitance The touch input can be detected at a relatively high voltage level, so that even if the touch input means has a small cross-section, the signal can be easily captured and the stylus pen can be input. Also, according to the size of the driving back, It is possible to increase the touch resolution and fine writing and drawing, and the active area can be configured as a single layer, which simplifies the manufacturing process and has a good yield.

1 is a perspective view illustrating an example of a conventional touch screen panel.
2 is a plan view showing another example of a conventional touch screen panel
Fig. 3 is a sectional view showing an example in which the touch screen panel of Fig. 2 is installed on a display device
Fig. 4 is an equivalent circuit diagram for detecting the touch capacitance in Fig. 3
5 is a waveform diagram illustrating a common voltage waveform of the liquid crystal display device
Fig. 6 is a diagram conceptually illustrating a conventional three-terminal type switching device
7 is a diagram illustrating the principle of detecting a touch input
8 is a circuit diagram showing a basic structure of the touch detection means according to the present invention.
9A and 9B are diagrams for explaining the correlation between the breakdown voltage of the TDI and the pre-charge voltage
10 is a diagram showing an embodiment of the present invention relating to the configuration of the touch detection section
11 is a view showing still another embodiment of the present invention relating to the configuration of the touch detection circuit section
12 is a sectional view showing an example of the configuration of the touch pad
13 is a sectional view showing another example of the configuration of the touch pad
14A and 14B are views showing an embodiment of a gesture using an area
Figs. 15A to 15C are diagrams showing still another embodiment of a gesture using an area
16 is a waveform diagram showing a process of detecting a touch signal
17 is a circuit diagram of a common voltage detecting circuit according to an embodiment of the present invention
18 is a waveform diagram of the common voltage detected by the common voltage detection circuit
19 is a diagram showing a detailed embodiment of the present invention relating to a common voltage detection circuit
20 is a view showing an embodiment relating to a method of recovering when a common voltage detection error occurs
21 is a flowchart for factory calibration for common voltage element extraction
22 is a diagram showing an embodiment of the present invention relating to a method of detecting a touch signal in synchronization with a common voltage
23 is a diagram showing an example of an actually detected common voltage
Fig. 24 shows an embodiment in which the magnitude of Vdrv varies according to a register setting; Fig.
25 shows an embodiment of the present invention relating to an embodiment of a touch screen panel
Figs. 26A to 26C are diagrams showing examples of various configurations of the touch pad
Figure 27 illustrates a touch screen panel as shown in Figure 5 of the disclosure,
28 is a view showing a conventional embodiment in which sensor signal lines are arranged above and below the touch pad
29 is a view showing an embodiment of a differential amplifier used in the present invention;
30 is a view showing an embodiment in which an ADC conversion section is connected to an amplifier output
31 is a flowchart showing a factory calibration method
32 is a diagram illustrating an embodiment of the present invention for setting an enforcement area of an RTC;
33 is a diagram showing an embodiment relating to the conventional capacitance type touch signal detection
Fig. 34 is a view showing a TFT configuration of a transverse electric field mode LCD substrate
35 is a view showing a conventional example of the background configuration of the transverse electric field mode LCD substrate
36 is a sectional view of the present invention applied to a transverse electric field mode LCD substrate
37 is a front view of the present invention applied to a transverse electric field mode LCD substrate.
38 is a view showing an embodiment of the present invention in which a touch pad is used in the background
39 is a view showing an embodiment of the present invention relating to the layout of the sensor signal line 22
40A to 40C are diagrams showing an embodiment of the present invention relating to a space charging unit between a touch detection unit and a sensor signal line
41 is a view showing one embodiment of a touch detection error by a conductor
42 is a view showing an embodiment of the present invention relating to the opening of the non-sensing pad
43 is a view showing an embodiment of the present invention relating to the opening of the sensing pad
44A and 44B show an embodiment of the present invention for extracting touch coordinates by data detected or calculated by a touch sensor
45 is a diagram showing an embodiment of the present invention for detecting a touch signal and a common voltage with a touch pad
46 is a view showing an embodiment relating to use of a function key;
FIG. 47 is a block diagram illustrating an embodiment of the present invention relating to a function key implementation
48 is a diagram showing one embodiment of a register setting applied to a function key;
49 is a view showing an embodiment of the present invention relating to the structure of a function keypad
50 is a view showing a conventional example of the configuration of an edge portion of a touch screen panel
51 is a view showing an embodiment of the present invention relating to the configuration of an edge portion of a touch screen panel
52 is a diagram illustrating an embodiment of the present invention using a plurality of TDIs
53 is a view showing an embodiment of the present invention for discharging static electricity
54 is a sectional view of a display device incorporating a touch screen panel
55 is an exploded perspective view of a display device incorporating a touch screen panel
56 is a diagram showing an embodiment of the present invention relating to touch group determination

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

The present invention relates to a touch detection means, a detection method and a touch screen panel using a driving back phenomenon and a display device incorporating such a touch screen panel. A method of detecting a driving back phenomenon caused by a difference in magnitude of a touch capacitance when an alternating driving voltage is applied to an attached driving capacitor, to be. The touch detection system according to the present invention detects a voltage caused by a driving-back phenomenon caused by a driving capacitor, a common electrode capacitance and a parasitic capacitance when a touch is not generated, a voltage generated by a driving- The influence of external noise or parasitic capacitance is minimized and the touch signal can be acquired more stably by extracting the magnitude difference between the two voltages.

The display device referred to in the present invention means any one of LCD, PDP, and OLED, or any other means for displaying other images.

Among the display devices listed above, the LCD requires a common voltage (Vcom) for driving the liquid crystal. For example, a small in-line LCD for a portable device uses a line inversion method in which a common voltage of a common electrode alternates one or a plurality of gate lines in order to reduce current consumption. As another example, a large LCD uses a dot inversion driving method in which the common voltage of the common electrode has a constant DC level. As another example, in the case of the transverse electric field mode LCD, the common electrode is formed in a part of the area of the LCD TFT substrate, and an image is displayed by a line-in version or a dot-inversion driving method. In the case of the transverse electric field mode LCD, a back ground is formed commonly in the entire color filter which is exposed to the outside through the back ITO, and is grounded to the ground signal for ESD blocking.

In the present invention, in addition to the electrode to which the common voltage Vcom is applied as described above, all the electrodes that commonly function in the display device are referred to as " common electrodes ", and alternate voltage, DC voltage, The voltage in the form of alternating in frequency will be referred to as " common voltage ".

The present invention detects a noncontact touch input of a finger or a touch input means having similar electrical characteristics. Here, the term " noncontact touch input " means that a touch input means such as a finger or the like touches the touch pad while the touch input means is spaced apart from the touch pad by a predetermined distance. The touch input means can be brought into contact with the outer surface of the substrate. In this case, however, the touch input means and the touch pad maintain the non-contact state. Accordingly, the touching action of the finger with respect to the touch pad can be expressed by the term " approach ". On the other hand, since the finger may be in contact with the outer surface of the substrate, the touching action of the finger with respect to the substrate may be expressed by the term " contact ". As used herein, the terms " approach " and " contact "

The components such as " to " described below are aggregates of unit function elements that perform specific functions. For example, when an amplifier of a signal is a unit functional element and an amplifier or signal converter The aggregate can be called a signal transformer. Also, " part " may be included in a larger element or " part, " or may include smaller elements and " parts. &Quot; Also, " part " may have its own CPU.

In the following drawings, thicknesses and regions are enlarged to clearly show layers and regions. Like reference numerals are used for like parts throughout the specification. Whenever a portion of a layer, region, substrate, or the like is referred to as being "on" or "over" another portion, it includes not only the case where it is "directly on" another portion, but also the case where there is another portion in between. Conversely, when a part is "directly over" another part, it means that there is no other part in the middle.

Further, the " signal " described in this specification refers to a voltage or a current collectively unless otherwise specified.

In the present specification, the term " capacitance " refers to a physical size and is used in the same sense as " capacitance ". On the other hand, a " capacitor " refers to an element having a capacitance that is a physical size. Capacitance may be created by design values and processes, or indirectly as if it were created naturally between two parallel signal lines at any distance. In the present specification, both the directly formed capacitor and the indirectly formed capacitor are referred to as " capacitors ".

In the present specification, the term " forcing "means that the level of a signal which has already been maintained is changed or connected to a signal in a floating state. For example, the signal applied to the on / off control terminal of the switching element may be used to mean that the existing low level voltage is changed to a high level, Off control terminal of the switching element of the switching element in order to apply a certain voltage for turning on / off the switching element.

In the present invention, " driving back phenomenon " or " driving back " is used in the same meaning and is abbreviated to "D / B "

In the present invention, the touch drive IC (Touch Drive IC) is shortened to TDI.

Further, in the present invention, when a touch is not generated, a voltage by D / B is detected, and when a touch is generated, a voltage by D / B is detected and by using the relationship of two voltages, Since the contact area of the touch means is determined, the meaning of detecting the voltage due to the D / B phenomenon and the meaning of detecting the touch signal are used in the same manner.

Fig. 6 conceptually illustrates a three-terminal type switching device among the switching devices used as one example of the charging means in the present invention. Referring to FIG. 6, the three-terminal switching device has three terminals, typically an on / off control terminal (Cont), an input terminal (In), and an output terminal (Out). The on / off control terminal is a terminal for controlling on / off of the switching element. When a predetermined voltage or current is applied to the terminal, the voltage or current applied to the input terminal is outputted in the form of voltage or current to the output terminal.

The three-terminal switching device referred to as a charging means in the present invention may be a relay, a CMOS (Complementary Metal Oxide Semiconductor) switch or a PMOS or NMOS, a bipolar junction transistor (BJT), a field effect transistor (Metal Oxide Semiconductor Field Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), a TFT (Thin Film Transistor), and an OPAMP, and they may be formed by a combination of the same species or different species.

The relay may be a 4-terminal type device in addition to the 3-terminal type device. As the charging means that can be used in the present invention, any device having a control terminal capable of turning input and output on / off irrespective of the number of input / output terminals and whose input / output is turned on / off by the on / off control terminal can be used .

On the other hand, as an example of a three-terminal switching device, a CMOS switch is formed by mutual combination of a PMOS and an NMOS, and input / output terminals are mutually connected, but on / off control terminals exist separately, The ON / OFF state is determined by being separately connected to the control signal. Relay is a device in which a voltage or current applied to an input terminal is output without loss when a current is applied to a control terminal, and a BJT is a device in which a voltage higher than a threshold value (threshold value) A current is amplified by a certain amount and flows from the collector to the emitter. The TFT is a switching element used in a pixel portion constituting a display device such as an LCD or an AMOLED, and is constituted by a gate terminal serving as a control terminal, a source terminal serving as an input terminal, and a drain terminal serving as an output terminal When a voltage higher than the threshold value is applied to the gate terminal and the drain terminal, a current depending on the magnitude of the voltage applied to the gate terminal is conducted from the input terminal to the output terminal.

Before describing a specific embodiment of the present invention, the principle of detecting a touch input will be briefly described with reference to Fig. 7, the touch pad 10 and the finger 25 are spaced apart by an interval of "d " when the finger 25 or similar conductive touch means approaches the touch pad 10, . Then, a capacitance "C" is formed between the finger 25 and the touch pad 10 as shown in the right equivalent circuit and the expression of Fig. When a charge having a magnitude of the quantity of charge "Q " is accumulated in a capacitor having a magnitude of capacitance" C " by supplying a voltage or current signal to a signal input line of the touch pad 10 having a capacitance "C & = Q / C. In the present invention, when a driving back having a correlation with the magnitude of the capacitance "C" occurs in the sensed pattern 10 connected to the touch detection unit, it is used Thereby detecting the touch.

8 is a circuit diagram showing a basic structure of the touch detection means according to the present invention. The touch sensing means according to the present invention includes a charging means 12, a touch pad 10, a sensor signal line 22, a driving capacitor Cdrv, a common electrode capacitor Cvcom, As shown in FIG.

The charging means 12 supplies a precharge signal to the touch pad 10 and is turned off to a turn off signal applied to the "on / off control terminal " named " Cont " (12-1) to high impedance.

The precharge signal is a voltage that charges the capacitors by applying a DC voltage to all the capacitors connected to the output terminal 12-1 of the charging means 12 before the touch signal is detected. Therefore, the charging means 12 is a switching element that performs a switching operation in accordance with a control signal supplied to the on / off control terminal, or a linear element such as an OPAMP that supplies a signal in accordance with a control signal.

When a three-terminal type switching element is used as the charging means 12 as in the embodiment of FIG. 8, by using a control signal supplied to the ON / OFF control terminal and a signal supplied to the input terminal, To all the capacitors connected to the output section 12-1 of the charging means 12 such as the touch pad 10, the driving capacitor Cdrv, and the common electrode capacitor Cvcom. The charging voltage can be DC voltage including zero volts and alternating AC voltage such as square wave or triangle wave or sine wave.

Such a charging voltage is related to a voltage used in a touch drive IC (hereinafter referred to as TDI) in which the touch detection system of the present invention is integrated. This relationship will be described with reference to FIGS. 9A and 9B as an example.

Assuming that the breakdown voltage of the TDI is 5V and the voltage of 5V or more is supplied to the TDI, the operating voltage of the circuit operating in the TDI should not exceed 5V. Assume that the potential difference due to D / B to be described later is 3V as in the embodiment of Figs. 9A to 9B. If the voltage of the output section 12-1 of the charging means 12 is 3V before the D / B occurs as shown in FIG. 9A, the voltage of the output section 12-1 of the charging means by the D / 6V, which exceeds 5V, which is the breakdown voltage of TDI, so that the TDI 30 is placed in the breakdown region.

In order to solve this problem, as shown in FIG. 9B, when 1 V is applied to the input section of the charging means in the state where the charging means is turned on and 1 V is charged to all the capacitors connected to the output section of the charging means, Even if a potential difference of 3 V occurs, the potential of the output section 12-1 is 4 V, so that the TDI 30 operates in the safe region.

As described above, an embodiment of the present invention may have a function of controlling a charging voltage for controlling a magnitude of a maximum voltage at the time of occurrence of driving back based on the internal pressure of TDI.

Fig. 10 shows an embodiment of the configuration of the touch detection unit 14 according to the present invention. 10, all the capacitors connected to the output section 12-1 and the output section 12-1 of the charging means 12 are connected to the touch detection section 10. [ The voltage generated by the D / B is transmitted to the buffer 14-1 of the touch detection unit 14 because the D / B phenomenon to be described later occurs in the capacitor connected to the output unit 12-1 of the charging means 12. [ do. Since the input terminal of the buffer 14-1 is usually a high impedance (hereinafter referred to as Hi-z), when the output section 12-1 of the charging means becomes Hi-z, the output section 12-1 ) And the buffer 14-1 are also in the Hi-z state. In this embodiment, the output section 12-1 of the charging means is directly connected to the buffer 14-1. However, instead of the buffer 14-1, the input of the MOS gate or the gate of the TFT is Hi-z Lt; RTI ID = 0.0 > terminal. ≪ / RTI > The reason why the output section 12-1 of the charging means and the touch detection section 14 are brought into the Hi-z state is that the detection time can be prolonged when the D / B phenomenon to be described later is detected in the Hi-z state to be. That is, in the Hi-z state, since there is no discharge path for the isolated charge, the level of the voltage formed by the D / B is maintained for a long time with minimum deformation.

The signal output from the buffer 14-1 is input to the amplifier 14-2. If the input terminal of the amplifier 4-2 is Hi-z, the point P in FIG. 10 may be directly connected to the input terminal of the amplifier 14-2.

When the magnitude of the P-point signal is low, the signal can be amplified using various amplifiers, but it is preferable to use a differential amplifier. This is because the point P is charged to the pre-charge voltage (or charge voltage) to be described later. In the amplification process, this charge voltage is removed through the differential amplifier, and only the voltage generated by the D / B phenomenon at the point P .

To remove the DC offset, such as the charge voltage when using a differential amplifier, a DC voltage must be applied to the negative terminal of the differential amplifier. In order to apply such a DC voltage, a DAC 14-4 is used or a " Ref voltage " 14-5 is used. The Ref voltage is a DC voltage having a constant potential as a reference voltage, In the power supply unit 47, which will be described later.

In FIG. 10, only one ADC is used in correspondence with one touch pad 10. However, if a plurality of touch detection circuits as shown in FIG. 10 are used, a plurality of ADCs can be used. There is an advantage that it can be reduced.

Although not shown in FIG. 10, a filter may be used between various functional units displayed in the touch detection unit 14. FIG. For example, a filter may be used for the previous stage of the buffer 14-1 and a filter may be used for the front end of the amplifier 14-2 or the amplification stage 14-2. These filters include various filters such as Bandwidth Low Pass Filter, Bandwidth High Pass Filter, or GCF (Grass Cut Filter), Ranking Filter, and Chopping Average Filter Can be used.

The touch pad 10 is formed of the entire transparency or metal. When the touch pad 10 is formed on the display device and is formed entirely of transparency, the entire transparency may be formed of indium tin oxide (ITO), antimony tin oxide (ATO), carbon nanotube (CNT), or indium zinc oxide A conductive transparent material or a transparent material having similar conductive properties. If the touch pad 10 is applied to a touch key such as a touch keyboard, a refrigerator, or a monitor that is not used as a display device, the touch pad 10 may be formed of a non-transparent material such as a metal.

The touch pad 10 may be patterned in various forms. For example, in the active area of the touch screen panel 50, isolated islands may be in the form of a dot matrix in which the islands are arranged in a matrix form, or linear patterns may be arranged to be transverse to the touch screen panel 50. The shape of the touch pad 10 will be described in detail in the following embodiments.

The sensor signal line 22 is connected to the touch detection unit 14 through a polarity of a capacitor formed when the finger 25 or a touch means having a similar conductive property (for example, a touch pen or the like) approaches the touch pad 10, And may be formed of a conductive transparent material similar to that of the touch pad 10, and in some cases, may be formed of a non-transparent material such as a metal. A specific embodiment of the sensor signal line 22 will also be described in the following embodiments.

The driving capacitor Cdrv is configured to apply a driving voltage for touch detection in the present invention. One end of the driving capacitor Cdrv is connected to the touch detection unit 14, the driving voltage is applied to the other end, and a D / B phenomenon .

As shown in Fig. 8, the output section 12-1 of the charging means 12 is connected to the touch detection section 14. Fig. One side of the driving capacitor Cdrv is connected to the output 12-1 of the charging means 12 and a detection signal is applied to the other end of the driving capacitor Cdrv. The D / B voltage proportional to the magnitude of the alternating driving voltage is applied to the touch detection unit 14 or the touch pad 14, and the detection signal is a voltage that alternates a plurality of different potentials, such as a periodic or acyclic wave such as a square wave, a sine wave, (10). The detected D / B voltage is detected at the intersection of the touch detection unit 14 and the output unit 12-1 of the touch pad 10 and the charging unit 12, so that the touch pad 10, Means that the D / B signal is detected at the output section 12-1 of the charging means 14 or the charging means 12 means that the D / B signal is detected at the same position.

The common electrode capacitor Cvcom shown in FIG. 8 is a capacitance formed when the touch pad 10 is opposed to the common electrode of the display device, one side connected to the touch detection unit 14, and the common voltage applied to the other side. At this time, although it may be directly connected to the common voltage and applied, it is usually electromagnetically induced and applied through a medium such as glass or air. For example, the touch pad 10 of FIG. 12 forms a touch capacitance and a touch means such as a finger 25 and also forms a common electrode capacitor Cvcom through the color filter 215 .

11 shows a case where an MOS (Metal Oxide Semiconductor) or a TFT or FET is used as an embodiment of the switching element, and an ADC (analog to digital converter) is used as the touch detector 14. The ADC converts the detected analog signal into a digital signal. The ADC converts the detected touch signal into a digital signal and transmits the digital signal to the signal processor 35 or the CPU 40 of FIG. 25.

11, when the finger 25 of the human body approaches the touch pad 10 at a predetermined interval, a touch capacitance Ct called "Ct " is formed between the finger 25 and the touch pad 10 do. Ct is a value set by the relational expression in FIG. 7 and can be freely adjusted by adjusting the distance between the touch means and the touch pad 10, the facing area, and the like. For example, if the area of the touch pad 10 is enlarged, Ct is also made larger according to the relational expression of FIG. On the contrary, the area of the touch pad 10 is made small and Ct is made small. In one embodiment, Ct can be designed from several fF (femto F) to several tens uF (micro F).

Cp in Fig. 11 is a parasitic capacitor, which is a total sum of capacitor values other than capacitors formed by the formula such as Ct or which can be manufactured as Cdrv, and which is connected to one side of the touch detection part 14 and the other side of which is connected to a ground . ≪ / RTI > Therefore, although a plurality of parasitic capacitors Cp having different grounds may be formed, only one parasitic capacitor connected thereto is assumed in this specification assuming only one ground. A plurality of parasitic capacitors or touch pads 10, which are generated between the sensor signal line 22 and the display device, are provided in the form of a dot matrix as shown in FIG. 25, and the sensor signal lines 22 connected to the parasitic capacitors Cp A parasitic capacitor generated between the sensor signal lines 22 when they are connected in parallel to each other, a parasitic capacitor generated in the connection portion when the TDI is connected to the touch pad 10, or a circuit portion connected to the sensor signal line in the TDI, There are various types of parasitic capacitors such as parasitic capacitors generated by interference. According to Equation 1 or Equation 2, the parasitic capacitors are inserted in the denominator of the equation to lower the D / B signal, so that the absence of parasitic capacitors is advantageous for touch detection.

11, a precharge voltage Vpre is applied to an input terminal of the charging means 12 and a control voltage Vg applied to the on / The precharge voltage Vpre is output through the output section 12-1. Therefore, all the capacitors connected to the output section 12-1 of the charging means 12 are charged with the precharge voltage Vpre.

In one embodiment, if the switching element is turned on when Vpre is 3V and Vg is changed from 0V (zero voltage) to 10V, the driving capacitors Cdrv, the touch capacitors Ct, And the potential of the touch detection part 14 to which the capacitance Cp is connected is 3V. When the control voltage Vg of the switching element is lowered from 10V to 0V and the switching element is turned off after the P point is charged, the P point, which is the touch detection part, becomes Hi-z, and the charge at the P point is isolated, and the driving capacitor Cdrv, The magnitude of the voltage detected at the point P is proportional to the magnitude of the driving voltage and a driving back phenomenon that correlates with the magnitude of the capacitors connected to the point P occurs.

Assuming that Cdrv, Cp and Cvcom are fixed values and the magnitude of the driving voltage applied to the driving capacitor Cdrv is constant, the magnitude of the voltage detected by the D / B phenomenon at the point P And is dependent on the capacitor Ct. Accordingly, the voltage detected by the touch detecting unit 14 changes according to the size of the touch capacitor Ct. Therefore, when the difference of the driving voltage due to the driving back phenomenon is detected, (Or the touch area) of the touching unit 25 and the touching unit 25 can be calculated, and it becomes possible to find the touch point.

FIG. 12 is a cross-sectional view illustrating an example of a touch pad structure according to the present invention, and FIG. 13 is a cross-sectional view illustrating another example of a touch pad structure according to the present invention. 12 illustrates a case where the touch pad 10 is mounted on a substrate formed separately from the display device, and FIG. 13 illustrates a case where the touch pad 10 is embedded in the display device. The formation of the common electrode capacitor Cvcom will now be described with reference to FIGS. 12 and 13. FIG.

As shown in FIG. 12, the display device 200 has a common electrode 220. In the case of AMOLED or PDP, there is no common electrode provided with a function to display picture quality. However, in the case of AMOLED or PDP, the Cvcom shown in FIG. 11 is provided between the various potentials formed on the TFT substrate of the AMOLED or the driving substrate of the PDP, A virtual electric potential formed by various electric potentials formed on the TFT substrate of the AMOLED or the driving substrate of the PDP is referred to as a common electrode.

The display device 200 may be any of the above-described various types of display devices, and the common electrode 220 may be a Vcom electrode of an LCD or any other type of electrode. The embodiment of FIG. 12 exemplifies the LCD of the display devices.

The display device 200 shown in Fig. 12 has a structure in which a liquid crystal is sealed between a TFT substrate 205 on the lower side and a color filter 215 on the upper side to form a liquid crystal layer 210. The TFT substrate 205 and the color filter 215 are bonded to each other by the sealant 230 at the outer portion thereof. Although not shown, a polarizing plate is attached to the upper and lower sides of the liquid crystal panel, and optical sheets constituting BLU (Back Light Unit) and BEF (Brightness Enhancement Film) can be installed together with the BLU.

A touch screen panel 50 is installed on the display device 200 as shown in the figure. 12, the touch screen panel 50 is attached to the upper portion of the display device 200 via an adhesive member 57 such as DAT (Double Adhesive Tape) or the like at its outer portion. An air gap 58 is formed between the touch screen panel 50 and the display device 200 or is filled with the contact member 58. The contact member 58 is a material for attaching the touch screen panel 50 and the display device 200 such as transparent silicone or OCA (Optically Clear Adhesive) or an adhesive resin.

A common voltage level for image display is applied to the common electrode 220 of the display device 200, and the common voltage is DC or a voltage that alternates the constant amplitude to a predetermined frequency. For example, the common voltage of the common electrode 220 is alternated as shown in FIG. 5 in a small LCD that performs line inversion, and a common voltage of a DC level, which is a voltage of a certain magnitude, .

A common electrode capacitor Cvcom is formed between the touch pad 10 and the common electrode 220 of the display device 200. [ If a precharge signal is applied to the touch pad 10, the common electrode capacitance Cvcom is charged with the precharge voltage having the common voltage as the ground by the precharge voltage. For example, if the common voltage is 5V and the pre-charge voltage is 3V at the pre-charge time, the common electrode capacitor is charged with a pre-charge voltage of 3V based on 5V. Since one end of the common electrode capacitance Cvcom is electrically grounded to the potential of the common electrode 220, the common electrode capacitance Cvcom is electrically grounded by the alternating voltage applied to the common electrode 220 when the common electrode 220 is an alternating voltage. The potential at the touch pad 10, which is the other end of the touch panel 10, is alternated. When the alternate potential overlaps with the touch signal using the D / B phenomenon, The rising and falling edges of the alternating common voltage should be avoided.

In the drawings, reference numeral 24 denotes a protective layer 24 for protecting the touch pad 10, and glass, plastic, vinyl, cloth, or the like is used.

13 shows another embodiment of the touch pad configuration in which the touch pad 10 is incorporated in the display device. Referring to FIG. 13, the touch screen panel 50 may be formed on the upper surface of the color filter 215, which is a part of the display device. As shown in the drawing, a common electrode 220 is formed under the color filter 215, and a touch pad 10 is patterned on an upper surface of the color filter 215. In the embodiment of Fig. 13, the protective layer 24 is replaced by a polarizer.

13, a common electrode capacitance Cvcom is formed between the common electrode 220 and the touch pad 10, and when the alternate voltage is applied to the common electrode, the potential of the sensor pattern 10 is induced to the alternating voltage When the voltage due to the D / B development induced by the alternating potential overlaps with the detection of the touch signal using the D / B phenomenon induced by the alternating driving voltage applied to the driving capacitor Cdrv, Therefore, the rising and falling edges of the alternating common voltage should be avoided when the touch signal is detected using the D / B phenomenon.

Referring again to FIG. 11, the output capacitance 12-1 of the charging means 12 is connected to the touch capacitance Ct, Cdrv, Cvcom, and Cp (), which are formed between the conductors such as the touch pad 10 and the finger 25, Respectively. Therefore, if a precharge signal such as an arbitrary voltage or current is applied to the input unit 12-2 while the charging means 12 is turned on, Cdrv, Ct, Cvcom, and Cp are charged to the precharge level, 14) The potential of the input terminal becomes the precharge level. Thereafter, if the charging means 12 is turned off, the signals charged in the four capacitors will maintain the precharge (or charge) signal level unless discharged separately.

To stably isolate the charged signal, the output section 12-1 of the charging means 12 and the input terminal of the touch detection section 14 are in the Hi-z state, and preferably have an impedance of at least 100Kohm or more. If the input of the touch detection unit 14 is a Hi-Sense signal, if the signal charged in the four capacitors is discharged while observing the touch input or isolating the charged signal by other means, It does not have to be z.

The touch detection unit 14 detects whether or not the signal level in the touch pad 10 fluctuates. Preferably, the touch detection unit 14 detects a touch when a touch is generated (i.e., when Ct is formed) in comparison with the magnitude of a voltage detected by a D / B phenomenon at the time of occurrence of a touch failure (i.e., ) Detects the size difference of the voltage detected by the D / B phenomenon and acquires the touch signal. The touch detection unit 14 may have various devices or circuit configurations. In the embodiment described below, an example in which the switching element and the amplifier are used as the touch detection unit 14 will be described, but the configuration of the touch detection unit 14 is not limited to such an embodiment.

The output of the buffer 14-1 by the driving voltage applied to one side of the driving capacitor Cdrv and Cdrv in the absence of a touch failure is determined by the following Equation (1).

≪ Formula 1 >

Since the touch capacitance Ct is added in parallel to the touch detection unit 14 at the time of touch generation, the voltage detected by the driving back at the input terminal of the touch detection unit 14 is determined by Equation (2) below.

&Quot; (2) "

In Equation 1 and Equation 2, DELTA Vsensor is a voltage generated by D / B at the input terminal of the touch detection unit 14, Vpre is a precharge voltage, and Vh is driving voltage applied to the driving capacitor Cdrv Vl is the low level voltage of the driving voltage applied to the driving capacitor Cdrv, Vcom is the common electrode capacitance, Cp is the parasitic capacitance, and Ct is the touch capacitance.

The touch detection unit 14 detects the voltage generated by Equation 1 or Equation 2 and will be described in detail as follows.

First, the D / B phenomenon is redefined by referring to Equation 1 and Equation 2 as follows. The D / B phenomenon is a phenomenon in which when there is at least one capacitor connected to the driving capacitor and a voltage of a predetermined magnitude is alternately applied to the other side (Vdrv applying portion in FIG. 11) of the driving capacitor, the potential at the point where the capacitors are commonly connected Is proportional to the magnitude of the voltage applied to one side of the driving capacitor and has a correlation with the capacitors connected in common. The correlation mentioned here means that the capacitance sum of all the capacitors connected in common is located at the denominator and the driving capacitance is located in the molecule.

The difference between Equation 1 and Equation 2 is that Equation 2 has Ct in the denominator. Since the capacitance Ct is a capacitor formed between the touch pad 10 and a touch means such as a finger, the capacitance Ct is a capacitance depending on the presence or absence of a touch, or depending on the opposing distance or the opposing area of the touch means 10 and the touch pad 10 The difference in Ct causes a difference in voltage induced by Equation 1 and Equation 2, so that it is possible to calculate the touch or touch area by detecting the voltage difference.

In the above formulas, Vh and Vl are the high level and low level of the driving voltage applied to the driving capacitor Cdrv, and the D / B phenomenon is the case where both the driving voltage is changed from high to low or from low to high Occurs. If the driving voltage changes from Vh = 5V to Vl = 2V, the D / B will be proportional to -3V, which is - (Vh-Vl). If the driving voltage changes from Vl = 2V to Vh = Is proportional to 3V (Vh-Vl).

When the driving voltage alternates from low to high, electric charge is supplied to the driving capacitor, and the electric charge supplied to the driving capacitor is supplied to all the capacitors connected in parallel with the driving capacitor so that the potential rises. Therefore, the driving voltage by D / same.

<Formula 1-1>

Also, at the moment when the driving voltage alternates from high to low, charges are discharged from the capacitors connected in parallel with the driving capacitor and the driving capacitor, so that the potential of the capacitors falls and the driving voltage by D / B is as follows.

<Equation 1-2>

This method is also applied to Equation (2).

On the other hand, Vh and Vl are values that can be easily set and will be determined within a range not exceeding the breakdown voltage of TDI described above. For example, assuming that Vpre = 3V and that the value due to the correlation of the capacitors is 0.1, the driving voltage by D / B will be 2V when Vh = 10V to Vl = 0V.

Also, Cvcom can be obtained from the following Equation (3).

&Quot; (3) &quot;

In Equation (3),? 1 is the complex permittivity of the medium existing between the touch pad 10 and the common electrode 220. In the case of FIG. 12, there is a glass, an air layer, a polarizing plate, and an adhesive for attaching the polarizing plate to the glass between the touch pad 10 and the common electrode 220, so that their complex permittivity becomes? 1 of the equation (3). S1 is an opposed area between the touch pad 10 and the common electrode 220 and can be easily obtained. 12, when the common electrode 220 is formed over the entire lower surface of the color filter 215, the facing area S1 is determined by the area of the touch pad 10. Also, D1 is the distance between the touch pad 10 and the common electrode 220, which corresponds to the thickness of the medium.

As you can see, Cvcom is a readily available value and a configurable value.

Ct can be obtained from the following Equation (4).

&Lt; Equation 4 &

In Equation (4),? 2 can be obtained from the medium between the touch pad 10 and the finger 25, and can be obtained from the complex permittivities thereof when a plurality of mediums are used. If a tempered glass is attached to the upper surface of the touch screen panel 50 in Fig. 12, the dielectric constant epsilon 2 can be obtained from the value obtained by multiplying the relative dielectric constant of the tempered glass by the dielectric constant of vacuum. S2 corresponds to the opposed area of the touch pad 10 and the finger 25. If the finger 25 covers all of the touch pads 10, then S2 corresponds to the area of the touch pad 10. If the finger 25 covers a part of the touch pad 10, S2 will be reduced by the area not facing the finger 25 in the area of the touch pad 10. D2 is the distance between the touch pad 10 and the finger 25 and therefore corresponds to the thickness of the protective layer 24 on the upper surface of the touch screen panel 50. [

As described above, Ct is a readily obtainable value and can be easily set by using the thickness of a material such as a protective layer 24 or reinforced glass which is placed on the touch screen panel 50. [

According to Equation (4), Ct is proportional to the opposite area between the finger 25 and the touch pad 10, so that the touch occupation rate of the finger 25 with respect to the touch pad 10 can be calculated from this. A method of calculating the touch occupation rate of the finger 25 is as follows. Referring to Equations (1) and (2), the difference is the difference in magnitude of the touch capacitance (Ct) depending on the presence or absence of a touch. Assuming that Vh, Vl, Vpre, and Cdrv are fixed values, only Ct can be extracted from Equation (1) and Equation (2). That is, the relationship of Ct = f (DELTA Vsensor, parallel connected capacitors, Vh, Vl, Vpre) holds. Assuming that? 2 and D2 are fixed values in Equation 4, the capacitance and the touch area are proportional to each other. Therefore, the area can be calculated by the extracted Ct.

When the area is obtained by using the equations (1) and (2), both the D / B voltage generated by the equation (1) and the D / B voltage generated by the equation (2) are used. The D / B voltage in Equation 1 is a value set in factory calibration or Real Time Calibration, which will be described later, and is an event that occurs before Equation 2. Since the D / B voltage according to Equation (2) is a voltage generated at the touch detection point, it is later than the detection point of the D / B voltage according to Equation (1). To obtain the touch area of the present invention, both the past D / B voltage such as factory calibration and real time calibration and the D / B voltage at the time of touch are used. For example, the minima or the numerator of a term of an equation for calculating the area include the voltage derived by Equation 1, and the minima or molecules of another term include the voltage derived by Equation 2, These terms are included in equations for area calculation.

Since the area of the finger 25 and the touch pad 10 are different from each other, it is possible to perform various gestures according to the contact area of the finger with respect to the touch pad 10. Referring to FIG. 14A, the finger 25 is in contact with the touch screen panel 50, and the finger 25 is opposed to the nine touch pads 10. Referring to FIG. 14B, the finger 25 faces the 15 touch pads. It is possible to increase or decrease the screen displayed on the display device (e.g., a landscape, a person, a keyboard, or the like) in conjunction with the contact area by changing the contact area while raising or lowering one finger.

15A to 15C are still another embodiment of a gesture using an area. As shown in FIG. 15A, the Apple iPad of US Apple has a 4-sided BM (Black Matrix), which is ergonomically designed to hold a finger on the iPad with two hands and to watch movies, to be. Since the pad is wider than 7 inches, it is necessary to use the BM in order to watch the Active Area (A / A) where the screen is displayed by holding it with both hands. However, such a BM is a factor for widening the screen size of a device to which the BM is applied, and thus there is a problem that portability is deteriorated.

 Figs. 15B to 15C are gestures using areas, which solve this problem. 15B shows a state in which most of the devices are A / A, except for the BM area as shown in FIG. 15A and the BM area of an absolute screen of several mm (for example, the gate signal line or the source signal line of the LCD passes) . If you do not hold the device by hand, such as when you are standing on a desk or looking up on a lap, the device displays the full screen as shown in Figure 15b.

However, when a finger is touched to one side of the screen by holding the device by hand, a BM having a correlation with the area of the finger touching the screen is displayed on the screen. Such a BM is not a BM that always exists as shown in FIG. 15A but a BM by an image. That is, when the finger comes in contact with the screen and reaches a certain area or more, the border BM can be displayed as a black series image with the finger touching the screen as an interface. In this case, since there is no reaction by the touch in the area indicated by BM, a graphical user interface (GUI) such as a touch icon is not included in the BM area indicated by a black or dark color. Also, if the finger is pushed in or out further into the screen, the BM will become wider or narrower in conjunction with the contact area of the finger and the screen. It is preferable that the upper and lower BMs are automatically generated when the finger 25 touches the left side or the right side or the left and right sides of the screen, and it is preferable that the area of A / A is kept at the same ratio as 4: 3 or 16: 9.

If the area of the finger 25 in contact with one side of the screen is smaller than a predetermined threshold value, it may not be recognized as a gesture for the grip. If the area is larger than a predetermined threshold value, .

It is possible to provide a portable electronic device that changes the area in which the image of the display device is displayed based on the gripping area and the position according to the embodiment of the present invention using the above-described technical principle.

16 is a waveform diagram showing a process of detecting a touch signal in the embodiment of FIG. A method of detecting a touch signal using a Driving Back phenomenon will be described with reference to the following description.

As described above, in the embodiment of the present invention, the common voltage may be an alternating voltage having a certain frequency, or may be an alternating DC voltage or an aperiodically alternating AC voltage. 16, the common voltage is periodically alternated in the regions 1 to 8, and the common voltage having the DC voltage that is not alternated in the regions 11 to 15 is exemplified. Explain that it can be implemented regardless. Meanwhile, the non-periodic Vcom can sense the rising edge and the falling edge and configure the embodiment in the same manner as the periodic Vcom of the present embodiment, which will be described later.

In order to proceed with this embodiment, a common voltage must be detected first. If the common voltage has a predetermined magnitude and alternates, if a rising edge and a falling edge waveform of the common voltage are applied during a period of detecting a driving back phenomenon, the waveform detected by the touch detection unit 14 Can be distorted. Therefore, the present invention avoids a point of time when the rising and falling edges of the common voltage occur, and detects a driving back phenomenon. However, according to another embodiment of the present invention, driving back generated when a driving voltage is applied to one side of the driving capacitor Cdrv and driving back due to a rising edge and a falling edge of a common voltage, (Driving Back) phenomenon may be detected at the same time to detect the touch input.

If the common voltage is a DC level that does not alternate, it is possible to detect driving back that is not dependent on the waveform of the common voltage. The TDI 30, which will be described later, includes a mode for sensing a rising edge and a falling edge of a common voltage when the common voltage alternates, and a mode for setting a mode in which the common voltage is not referred to when the common voltage is not alternated . When the common voltage is not alternated, it is possible to easily detect the driving back phenomenon because the common voltage is not detected and the touch detection process is not synchronized with the common voltage. The driving back voltage due to the driving voltage applied to the Cdrv can be detected by avoiding the alternate time point when the common voltages are alternated. Therefore, an advantage of this method is that the common voltage is alternately displayed or alternately It is possible to detect a driving back by a touch in any case.

The embodiments of the present invention described below disclose a method of performing touch detection by detecting and synchronizing a common voltage dynamically based on an alternating characteristic of a common voltage.

* Common voltage Alternate  In the region Example

First, after detecting a rising edge or a falling edge of a common voltage by detecting a waveform of a common voltage, the on / off control unit of the charging means 12 is turned on after a certain period of time (in this embodiment, Thereby precharging the capacitors. Referring to FIG. 11, the capacitors to be charged at this time are Cdrv, Ct, Cvom, Cp. The charge voltage Vpre may always be maintained at the charge voltage level, or it may be maintained at any potential before the charge voltage level is maintained just before Vg is turned on.

Referring to FIG. 11, the charge voltage Vpre is connected to the input unit 12-2 of the charging means 12 and is transferred to the output unit 12-1 in the turn-on state of the charging means to charge the capacitors. At this time, the voltage drop due to the resistance between the input section 12-2 and the output section 12-1 of the charging means 12 is ignored.

A region for applying the charging voltage Vg can be applied anywhere. For example, the region 4 is an area in which the common voltage alternates and is a region in which the voltage magnitude due to D / B due to the alternating common voltage is changed. However, since the charging voltage is applied, no voltage change due to the common voltage is issued . After the capacitors are charged, the on / off control unit of the charging means 12 is turned off so that the output unit 12-1 of the charging means 12 is in the Hi-z state, If it is used and is in the Hi-z state, the capacitors will maintain the charge voltage. The section for maintaining the charge and charge voltage in this manner is shown in Fig. 16 in the areas?,?, And?. A predetermined discharge may occur due to the fact that the output section 12-1 of the charging means 12 and the input terminal of the touch detection section 14 are not ideal Hi-z in regions 1, 4, and 7. However, in this embodiment, .

의 값(Calculated Value)은 0.2로 가정하였다. 따라서 D/B 현상이 발생하는 영역 ②,⑤.⑧의 전압은 <수식1-1>에 의해 4V가 된다. <수식1-1>은 터치가 발생하지 않은 경우의 D/B 현상에 의한 검출전압이며, <수식2>는 터치가 발생한 경우의 검출전압이다. In this embodiment, detection of the voltage by D / B at the moment when the driving voltage is changed from low to high is exemplified, and the charging voltage is 2V. Also, the amplitude of Vdrv is 10V,

The calculated value is assumed to be 0.2. Therefore, the voltage of the area (2), (5), and (5) where the D / B phenomenon occurs is 4V according to Equation (1-1). Equation 1-1 is the detection voltage due to the D / B phenomenon when no touch occurs, and Equation 2 is the detection voltage when the touch occurs.

의 값이 0.1이라고 한다면, 영역⑧의 전압은 3V가 되어야 한다. 전술한바와 같이, 터치검출부(14)는 터치가 안되었을 때의 전압인 4V를 기준으로 하여, 터치가 되었을 때의 전압인 3V를 검출하고 기준값인 4V와의 차이(Difference)를 연산하여 터치유무(Touched or Untouched)를 판단하고 터치면적(Touched Area)를 연산한다.If a touch occurs in the area ⑦, the voltage of the area ⑧ should be changed by the formula 2. Therefore,

Is 0.1, the voltage of the area 8 should be 3V. As described above, the touch detection unit 14 detects 3V, which is the voltage at the time of touching, based on 4V, which is the voltage at the time when the touch is not performed, and calculates the difference between the touch voltage and 4V, Touched or untouched) and calculates a touch area (Touched Area).

Since the time required for touch detection in the touch detection area such as the areas 2, 5, and 8 is only tens of us and the discharge amount of the detected voltage is insufficient, in this embodiment, by D / B The discharge in the region where the voltage is detected and the touch is judged is ignored. Therefore, the voltage due to D / B is 2V according to Equation (1-2) even in the section where the driving voltage returns to 0V as in the areas (3) and (6).

On the other hand, referring to the boundary between the region 8 and the region 9, this interval is a period in which the D / B phenomenon occurs due to the common voltage. As the common voltage is changed from high to low, the voltage when changing from the region 8 to the region 9 It is changing. Referring to Equations (1) and (2), when the magnitude of the voltage applied to one side of the commonly connected capacitors is changed, the potential of the common connection of the capacitors is changed to D / , A potential fluctuation for D / B at the point P occurs when an alternating driving voltage is applied to the driving capacitor Cdrv or when a common voltage alternately applied to the common electrode capacitor Cvcom is applied .

When touch occurs and Ct is formed, the voltage by D / B by the alternating common voltage is expressed as follows.

&Lt; Eq. 5 &

는 터치검출부(14)에서 D/B에 의한 드라이빙전압이며, Vpre는 공통전압의 교번에 의한 D/B 전압이 발생하기 직전에 공통으로 접속된 커패시터들의 전위이며, VcomH는 공통전극커패시터(Cvcom)에 인가되는 공통전압의 하이 레벨 전압이며, VcomL 는 공통전극커패시터(Cvcom)에 인가되는 공통전압의 로우 레벨 전압이며, Cdrv는 드라이빙 커패시턴스이며, Cvcom은 공통전극커패시턴스이며, Cp는 기생커패시턴스이고 Ct는 터치커패시턴스이다. In Equation (5) above,

V is the potential of the capacitors connected in common immediately before the D / B voltage is generated by the alternation of the common voltage, and VcomH is the potential of the common electrode capacitor Cvcom, VcomL is a low level voltage of a common voltage applied to the common electrode capacitor Cvcom, Cdrv is a driving capacitance, Cvcom is a common electrode capacitance, Cp is a parasitic capacitance, and Ct is a high- It is touch capacitance.

가 0.05이라고 가정하면, 영역⑧에서의 전압 즉 Vpre는 3V이므로 3V-10*0.05V=2.5V로서 영역⑨의 전압은 2.5V가 된다. 또한 영역(10)에서 드라이빙전압인 Vdrv에 의한 전압강하는 2V이므로 2.5V는 0.5V로 전위가 낮아지게 된다.In Equation 5, (VcomH-VcomL) is 10 V

Is 0.05, the voltage in the area 8 is 3V, that is, 3V-10 * 0.05V = 2.5V, and the voltage in the area 9 is 2.5V. Further, since the voltage drop due to the driving voltage Vdrv in the region 10 is 2V, the potential becomes 2.5V at 0.5V.

Equation (5) is a voltage detection formula based on the alternation of the common voltage when a touch occurs, and when there is no touch, there is no Ct of the denominator.

&Quot; (6) &quot;

는 터치검출부(14)에서 D/B에 의한 드라이빙전압이며, Vpre는 공통전압의 교번에 의한 D/B 전압이 발생하기 직전에 공통으로 접속된 커패시터들의 전위이며, VcomH는 공통전극커패시터(Cvcom)에 인가되는 공통전압의 하이 레벨 전압이며, VcomL는 공통전극커패시터(Cvcom)에 인가되는 공통전압의 로우 레벨 전압이며, Cdrv는 드라이빙 커패시턴스이며, Cvcom은 공통전극커패시턴스이며, Cp는 기생커패시턴스이고 Ct는 터치커패시턴스이다.In Equation (6) above,

V is the potential of the capacitors connected in common immediately before the D / B voltage is generated by the alternation of the common voltage, and VcomH is the potential of the common electrode capacitor Cvcom, VcomL is a low level voltage of a common voltage applied to the common electrode capacitor Cvcom, Cdrv is a driving capacitance, Cvcom is a common electrode capacitance, Cp is a parasitic capacitance, and Ct is a high- It is touch capacitance.

Referring to Equation (5) and Equation (6), it is also possible to detect a voltage by D / B by applying an alternating driving voltage to the driving capacitor (Cdrv), but the common electrode capacitor (Cvcom) It is also possible to detect a touch by detecting a change in the voltage caused by the D / B phenomenon. In this embodiment, it is preferable to remove the Cdrv term in the denominator of Equation (5) and Equation (6) in order to increase the detected voltage, i.e., increase the detection sensitivity. Since Cdrv can be formed inside the TDI 30, it is possible to remove Cdrv in order to detect the D / B voltage by alternating the common voltage. In order to remove the Cdrv, a CMOS It is possible to determine whether or not the Cdrv is connected to the touch detection section when the switching element such as a TFT or the like is connected and the switching element is turned on / off.

When Cdrv is removed and the voltage by D / B is detected by the alternation of the common voltage, the following equation is obtained.

&Quot; (7) &quot;

&Quot; (8) &quot;

&Lt; Equation 7 > is an arithmetic expression when no touch is made and &quot; Equation 8 &quot; is an arithmetic expression when a touch is made.

12, the touch screen panel 50 may be mounted on the upper surface of the display device 200 or the touch screen panel 50 may be mounted on the upper surface of the display device 200 as shown in FIG. ) Or directly on a TFT substrate.

* Common voltage Alternate  In an area that does not Example

An example in which the common voltages are not alternated taking the regions 11 to 15 as an example will be described as follows.

A display device using an LCD for performing dot inversion is a display device in which the common voltage applied to the common electrode is a DC level and the AMOLED or PDP is a common display device having no common electrode or alternating common voltage. 12 and 13, when the touch screen panel 50 is coupled with the display device, the touch detection unit 14 performs driving by common voltage as shown in Equations (5) and (6) There is no need to consider voltage fluctuations and a complicated process of detecting a common voltage as a means for avoiding a rising edge or falling edge of a common voltage and detecting a touch can be omitted.

The area 11 and the area 14 in FIG. 16 are the periods in which the charging voltage is maintained when the charging means 12 is charged with the charging voltage Vpre and the charging means 12 is turned off. The area ⑫ and the area ⑮ are areas where the voltage by the D / B is formed by the driving voltage Vdrv and the touch is checked according to the magnitude of the voltage. In the present embodiment, 4V is detected on the assumption that no touch occurs. The area ⑬ is a section where a voltage drop of 2V occurs when the driving voltage is changed from high to low, and the potential is maintained at 2V.

Even when a common voltage of a DC level is applied to the common electrode, an alternate voltage is generated in the common electrode due to the noise generated in the switching device of the display device or in the process of driving the liquid crystal of the LCD TFT substrate . Generally, ITO (Indium Tin Oxide) is used as a common electrode and the sheet resistance of ITO is about several hundred ohm. When the electrode is used in a wide area such as 7 inch or 10 inch, The resistance increases at a remote place, and the common voltage far away from the common voltage applying portion can be changed in size by noise. These noises are periodic noise and non-periodic noise. This noise may correspond to VcomH and VcomL in Equation (5) and Equation (6). That is, when noise is alternated from -1V to 2V, VcomH is 2V and VcomL is -1V.

When the alternating voltage of the noise is small, the voltage magnitude change according to Equation (5) or Equation (6) is small and does not affect the D / B voltage by driving the driving capacitor (Cdrv) If the voltage is large, it affects the D / B voltage due to the driving of the driving capacitor Cdrv. Therefore, the touch signal should be detected by avoiding such noise. Therefore, it is necessary to detect a rising edge or a falling edge of the noise, which is the same as the common voltage, and to detect the touch signal by avoiding the edge section.

When there is an alternating common voltage in the embodiment of FIG. 16, a touch signal must be detected in synchronization with the common voltage, and a CPU of a set that uses touch coordinates and calculates the touch coordinates, for example, The report time to report to a central processing unit such as A4 is determined in synchronization with the alternating cycle of the common voltage. However, when there is no alternating common voltage, since the touch signal can not be detected in synchronization with the common voltage, the touch should be detected by setting the detection period.

In Fig. 16, t10 is a period for detecting a touch signal when there is no alternating common voltage. This period can have a time duration from several us to several milliseconds, and the touch signal is reported to the CPU of the set in synchronization with this period.

On the other hand, when a signal is distorted due to a common voltage, such as at the boundary between the area 8 and the area 9, when the touch signal is detected in the areas 2, 5, and 8 as the touch signal detection period, the touch detection part 14 reflects Considering that the touch operation can be performed but the size of the alternating common voltage is discontinuous but the size can not be predicted, it is not easy to detect the touch considering the D / B voltage due to the common voltage. Therefore, it is possible to avoid such a problem by avoiding the rising edge or the falling edge of the common voltage and detecting the touch in a section where the common voltage has a flat DC level.

As described above, according to the embodiment of the present invention, touch detection can be performed by determining the touch detection timing dynamically by performing synchronization with the common voltage based on the characteristics of the common voltage. Hereinafter, an embodiment for detecting the common voltage will be described in detail.

17 is an embodiment of a common voltage detecting circuit for detecting a common voltage. A method of detecting the edge portion of the common voltage will be described with reference to FIG.

FIG. 17 is an embodiment in which a common electrode capacitor Cvcom formed between the touch pad 10 and the common electrode 220 is formed in the common voltage detecting unit 15 in FIG. 12 and FIG.

As described above, when a plurality of touch pads 10 of FIGS. 12 and 13 are used to form the touch screen panel 50, a parasitic capacitor Cp is formed between the sensor signal lines 22, Cp is formed in the process of assembling, so Cp must be considered in the common voltage detecting circuit.

In order to detect the edge of the common voltage, it is necessary to make the common electrode capacitor Cvcom to Hi-z. To this end, the charging means 12, which can make Hi-z state when turned off, The common voltage detector 15 is required. The common voltage detector 15 is supplied with an upper reference voltage (URL) and a lower reference voltage (LRL), and the reference voltage can be generated in the TDI or supplied to the TDI from the outside have.

It is preferable that the capacitors connected to Cvcom and Cvcom are also charged with an appropriate DC level in order to facilitate the setting of such URL or LRL or to ensure that the detected output waveform of Vcom is included within the range of the operating breakdown voltage of TDI Do.

18 is a waveform diagram of the common voltage detected by the common voltage detecting circuit. Referring to FIG. 18, Real Vcom at the top of FIG. 18 is an actual Vcom applied to the common electrode 22 in FIGS. 12 and 13. Assuming that Vcom is alternated from 0V to 5V and that Vpre_com which is a charging voltage is 2.5V, 2.5V which is a charging voltage is charged in Cvcom and Cp in a state where the charging means 12 is turned on, The potential Vp at the point is 2.5V.

Common voltage detection proceeds in two steps. The region 1 in Fig. 18 is a time point when the common voltage is not yet detected. This is the instant when the power is turned on or the moment when the common voltage is not generated during the process of detecting the common voltage and detecting the subsequent common voltage in synchronization with the detected common voltage.

When the common voltage is not yet detected as in the region 1, the charging means 12 is first turned on to apply the charging voltage Vpre_com to Cvcom and Cp, and the charging means is turned off to detect the rising edge or the falling edge of the common voltage Waiting to be. When the charging means is turned off, Cvcom is in a Hi-z state, so that when a rising edge or a falling edge voltage is applied to the common electrode 220 in FIGS. 12 and 13, a voltage difference according to Equation (7) occurs.

Assuming that the detected voltage Vsensor in Equation 7 is 2 V, when the common voltage is a rising edge, the potential at point P is 4.5 V in FIG. 17 and the potential at point P is 0 when the common voltage is falling edge, 5V. Therefore, when Real Vcom is a rising edge as in region 1, the detected Vcom becomes 4.5V.

값은 미리 예측가능한 값이므로 △Vsensor도 어느정도는 예측이 가능하다.

의 계산값이 약 2V정도로 예상된다고 가정하면, 2.5V의 Vpre_com에 의해 △Vsensor는 4.5V와 0.5V를 스윙(Swing 또는 교번)하게 될 것이다. 이 경우, 검출된 공통전압이 충전전압인 2.5V보다 높게 검출되면 현재 공통전압이 rising edge 상태라고 판단 할 수 있으며, 2.5V보다 낮게 검출되면 falling edge상태라고 판단할 수 있다. In Equation 7,

Since the value is a predictable value in advance,? Vsensor can be predicted to some extent.

Is expected to be about 2V, the Vsensor will swing (swing or alternate) 4.5V and 0.5V by Vpre_com of 2.5V. In this case, if the detected common voltage is detected to be higher than the charge voltage of 2.5V, it can be determined that the current common voltage is a rising edge state, and if it is detected to be lower than 2.5V, it can be determined that the falling edge state is present.

Referring to FIG. 18, the URL is set to 3V and the LRL is set to 2V. In the embodiment of FIG. 18, the URL may be a reference voltage for detecting a rising edge, and a voltage higher than the URL may be a rising edge. The URL in the embodiment of FIG. 18 is only one embodiment, and voltages higher than 2.5V and lower than 4.5V can all be set to URL. On the other hand, in the embodiment of FIG. 18, the LRL is set to 2V, and it is possible to determine that the common voltage detected lower than LRL is a falling edge. A voltage between 2.5 and 0.5 V can be arbitrarily set in the LRL.

Referring to Equation (7), since the D / B voltage detected by the alternation of the common voltage depends on the charge voltage, the charge voltage must be referred to in order to set the URL and LRL.

After the common voltage is detected, subsequent common voltage detection must be performed in synchronization with the detected common voltage. This is because, when a common voltage is alternately generated in the display device, the common voltage is normally repeated periodically high and low, so that when a common voltage in a certain state is detected, when the next common voltage having the opposite polarity is predictable do. For example, if the alternating period of the common voltage is 30us, it can be predicted that a falling edge will be detected after 30us after the common voltage detection that maintains the high state after the rising edge, and the low state will be maintained. Therefore, when the state of the detected common voltage, that is, whether it is in the high state or in the low state, it becomes possible to predict the state of the next detected common voltage within a predetermined time. Therefore, if a common voltage is not detected within a predetermined time, it is possible to proceed with an appropriate exception process because the common voltage detection system is abnormal or a common voltage is not generated.

Region 2 in Fig. 18 explains the process of detecting the next common voltage in synchronization with the detected common voltage. Assuming that Vg_com applied to the on / off control terminal of the charging means 12 in Region 2 is continuously Low in Region 2, the output of the charging means 12 is in the Hi-z state, The potential will continue to be 4.5V (neglecting the potential change due to discharge). In this state, when the charging means 12 is turned on (Vgcom_on determines the turn-on time) and the charging voltage Vpre_com is supplied to Cvom and Cp, the charging voltage is maintained at 2.5 V even after the charging means is turned off do. "Wait_vgcom", which is the time at which the charge voltage for detecting the next common voltage is applied after the common voltage is detected, can be arbitrarily set, and it is possible to set a desired time using a registor for setting this. For example, if the period of the common voltage is 30us, "Wait_vgcom" is a changeable time within 30us, and it is possible to freely set 1us, 5us, 10us, and so on.

For example, assuming that the period of the common voltage is 30us, "Wait_vgcom" is set to 1us, and the charging means 12 Quot; Vgcom_on " which determines the turn-on time is set to 25us, the potential at the point P in Fig. 17 is 2.5 V for at least 27 us, and since the charging voltage is applied, the fluctuation of the voltage due to the noise does not occur, The probability of a malfunction due to a failure can be greatly reduced.

In the embodiment of FIG. 18, the period of the high period and the period of the low period of the common voltage are different from each other. Therefore, it is desirable that "Wait_vgcom" can be set separately in the interval in which the common voltage is high and in the interval in which the common voltage is in the high level. If the interval "Wait_vgcom" is set using the register, "Wait_vgcom_hi" Quot ;, and &quot; Wait_vgcom_lo "will be a set value in a section in which the common voltage is low.

As described above, according to the embodiment of the present invention, it is possible to efficiently detect the common voltage in which the lengths of the high section and the low section are different.

Region 3 is a period in which the common voltage remains in the low state after the falling edge. The common voltage is detected in region 2, and after Wait_vgcom, Cvcom is charged and the next common voltage is detected. The potential at this time is 2.5 V and the common voltage detected by the D / B phenomenon due to the falling edge of the common voltage The potential is 0.5 V. Since this is a voltage lower than 2 V which is the LRL, the common voltage detector 15 detects this and outputs a signal indicating that the falling edge has been detected. Generates a signal necessary for touch detection to be described later or generates a signal for detecting a next common voltage using this signal. Such " detection result &quot; may be output to the outside of the TDI. To accurately determine the high or low level of the high or low level, or to accurately measure the time of the high or low section.

19 is a detailed embodiment of the common voltage detecting circuit. Referring to FIG. 19, the common voltage can be detected by the common voltage detecting circuit, but can be supplied from outside the TDI. The TDI 30 has a means for determining whether to detect the common voltage inside the TDI or use an external common voltage. With the setting of such means, the switching section 16 determines whether to use the common voltage applied from the outside or the common voltage detected by the common voltage detecting section 15.

The common voltage detector 15 uses a comparator 19. The comparator 19 has a comparator 19a for detecting the rising edge of the common voltage and a comparator 19b for detecting the falling edge. The URL is used as the reference voltage in 19a and the reference voltage is used in 19b. In the comparator 19a for detecting the falling edge, the comparator 19b outputs a low or low signal when the detected common voltage is lower than the LRL. do.

12 to 13 and 19, since the touch detection touch pad 10 detects the touch while detecting the common voltage, if it is assumed that the touch state is the touch state at the moment of detecting the common voltage, Equation (7) The common voltage can not be detected by using Equation (8). If Equation (8) is used, the level of the high and low of the common voltage detected due to the addition of Ct to the denominator is different in contrast to the case where there is no Ct, but when the difference is not large, the level of the URL or LRL is changed It becomes possible to detect the common voltage. If the detected high voltage or low voltage of the common voltage is difficult to use due to insufficient discrimination power or noise, the common voltage is detected using the non-touching touch pad 10 can do. As will be described later, in the touch screen panel 50, several tens or hundreds of the touch pads 10 are used. Accordingly, a plurality of touch pads are connected to the common voltage detecting circuit by using a multiplexer (hereinafter, referred to as Mux), thereby making it possible to select a touch pad that does not generate a touch.

The input connected to the point P in the common voltage detector 15 in Fig. 17 or 19 should be Hi-z. To this end, a device having a Hi-z input, such as a buffer or a gate connection, may be connected to the P point. It is also possible to detect the common voltage level using the ADC and transmit it to a CPU inside the TDI or a CPU outside the TDI, and detect the edge and the level of the common voltage by comparing with a predetermined URL or LRL. Although not shown, a filter may be used for the common voltage detector 15, and a LPF, HPF, ranking filter, or GCF may be used as the filter.

In the case where the display device is an LCD, a common voltage may not be generated, or a change such as a lengthening or a shortening of the period may occur in a backpoch of a frame image or a frone poach period. Or, abnormal operation of the common voltage detector 15 or noise superimposed on the common voltage may fail to detect the common voltage, or a detection error may occur. Even if such a problem occurs, the operation of the touch detection circuit for touch detection and the touch detection must be continued, and a countermeasure against common voltage detection error is required.

* Measures against common voltage detection error

One) Factory Calibration

Factory Calibration (hereinafter referred to as "CAL") is a factory-calibrated system that detects common voltages in a stable environment and stores the detected common voltage factors in a memory so that data stored in memory To continue the touch detection. Elements related to the common voltage include the duration of the high section of the common voltage, the duration of the low section, the back poach of the image frame, and the duration of the high and low sections of the common voltage in the front poach. When the factory calibration is completed and several elements of the common voltage are stored in the memory, an exception handling method according to the defective common voltage type in the process of detecting the common voltage is as follows.

(1) When the common voltage can not be detected

As described above, the time at which the next common voltage appears after the common voltage is detected can be roughly known by calculation, and the accurate time can be measured using the output for the external monitor of the common voltage connected to the outside of the TDI . Therefore, if the common voltage is not detected at the expected time, the CPU 40 or the signal processing unit 35 of the TDI, which will be described later, extracts the duration of the missing common voltage among the common voltage elements stored in the memory, .

* For example, the common voltage of the low section is detected and the common section of the high section should be detected after 30us. The time of 30us is detected in the factory cal. Process and stored in memory. Accordingly, if the rising edge of the common voltage is not detected even after the wait for 30 us, the CPU 40 generates a virtual rising edge start point, generates a necessary signal for detecting the next common voltage in synchronization with the rising edge, . The signal required for the touch detection includes the charging time using the charging means 12 mentioned in the embodiment of Fig. 11, the adjustment of the time for applying the driving voltage after the charging time, the setting of the time for starting the touch detection, .

2) When the detected common voltage error occurs

20 is an embodiment of a method for recovering a common voltage detection error when it occurs. Referring to FIG. 20, the common voltage 1 (Detected Vcom1) detected in comparison with the value stored in the memory is generated quickly, and the detected common voltage 2 (Detected VCom2) is generated later. One way to recover from a detection error is to set the window based on the value stored in memory. For example, if the duration of the high period of the common voltage stored in the memory is 30us, if a window of 5us is set, the detection time becomes 30.5μs, and the common voltage detected within 25us to 35us is regarded as normal, Defective. The window at this time can be set arbitrarily, and the TDI 30 has means for setting the window. For example, the window must be set through a register or written to a certain area of the nonvolatile memory such as a flash memory.

As in the case of detected common voltage 1 (detected Vcom1), the common voltage detected earlier than the window is regarded as noise and is ignored. If the common voltage is not detected until 35us, which is the last time of the window, Recalls the duration of the common voltage and generates a signal for detecting the next common voltage in synchronization with the generation of a signal for detecting the touch. Assuming that the duration of the row region is 25us, for example, 5us has already passed, and thus generates necessary signals in synchronization with 20us. If the common voltage is not detected for 35us by adding 30us written in the memory and 5us which is the window area as in the embodiment of the detected common voltage 2 (detected Vcom2), the CPU generates a virtual common voltage of 20us as described above And generates a necessary signal in synchronization therewith.

An embodiment of the present invention, as in the above-described configuration, Cal performs common voltage synchronization by dynamically responding at the time of non-detection or detection of a common voltage using common voltage information and window information stored in advance.

2) Real time Calibration ( Real Time Calibration , Below RTC )

When the display is an LCD, it is the LCD Drive IC (LDI) that generates the common voltage. LDI is an IC that controls the gate timing of a TFT by applying a pixel voltage to the TFT of the LCD. An oscillator (hereinafter, referred to as an OSC) is used to generate a common voltage in the LDI. The OSC changes the temperature of the OSC because the resistance and the value of the capacitor constituting the OSC change due to the temperature change. If this change is large, fac. If the common voltage is detected by referring only to the elements stored in cal., if this value is set outside the window area, an error may occur in exception processing. In order to avoid such a problem, there is a method of storing elements of the common voltage detected in real time in a memory and using it in exception processing, which is called an RTC.

Also fac. It is also possible to store the elements extracted from RTC in memory without executing cal.

fac. Since the RTC requires a separate memory area after the cal. There must be a means to determine whether to use the cal element or the detected element in the RTC. Although it is reasonable to use the RTC element, the RTC element has fac. cal. Since there is a higher probability of detection error due to noise than element, fac is an absolute criterion. Because the cal element is sometimes needed, RTC and fac. You need a means to select the cal element. These means can be determined by changing a register set in the TDI or storing it in a nonvolatile memory.

FIG. 21 is a diagram for explaining fac. It is a flow chart for cal. Referring to FIG. 21, fac. The first step of cal. is to determine whether to detect the common voltage. As described above, in the case of an LCD having dot inversion, since the common voltage is at the DC level, it is not necessary to detect the common voltage. Therefore, the means for determining whether to detect the common voltage should be provided in the TDI. Such means may use a register or a non-volatile memory.

If a common voltage is detected, a signal as shown in FIG. 16 is generated and a common voltage detecting circuit as in the embodiment of FIG. 17 or 19 is configured to detect a common voltage.

When the common voltage detection is completed, referring again to FIG. 21, the common voltage elements detected by the common voltage detector 15 are stored in a memory.

Assuming that the absolute time required to detect the touch signal and calculate the detected signal is 40us, if the duration of the common voltage is less than 40us, the touch detection avoids the rising edge or falling edge of the common voltage by synchronizing with the common voltage, Can not be detected. When the duty of the common voltage is smaller than the time required for the operation of the touch signal, the duty of a plurality of common voltages may be used. For example, assuming that the duration of the high and low sections of the common voltage is 30us and the time required for the touch signal calculation is 40us, the touch detection unit 14 detects the rising edge and the falling edge of the common voltage and outputs only one signal And the touch signal can be calculated in synchronization with this. Or the TDI 30 may generate signals necessary for the touch signal operation in synchronization with one of the two detected common voltage signals.

The duration of the common voltage is too long, so that the time required for the touch signal calculation may be multiplied by a plurality of times. For example, the duration of the common voltage is 100us and the time required for the touch operation is 40us. In this case, it is possible to make the report time to report the touch coordinates more quickly by performing a plurality of touch operations at one common voltage, and this is a means for accelerating the response speed of the touch. The TDI 30 must be provided with a means for determining whether to calculate a touch signal for a plurality of common voltages or a touch signal for a plurality of times within one common voltage period. The TDI 30 may be implemented as a register or a memory.

According to the above-described configuration, it is possible to determine the timing of the effective touch detection calculation based on the duration of the common voltage and the time required for the touch operation.

The voltage due to the D / B induced at the rising edge or the falling edge of the common voltage is expressed by Equation (7) and Equation (8), and these signals are expressed by Equation (1) and Equation (2) The voltage due to the D / B phenomenon, which is a touch signal, must be detected by avoiding the point at which the rising edge or the falling edge of the common voltage is generated.

The distortion of the voltage according to Equation (7) or Equation (8), which is the D / B phenomenon using the common voltage when the detection using Equation (1) or Equation (2) is completed, The term "Vpre_com" in the expression (8) becomes DELTA Vsensor which is the voltage detected in the expression (1) or (2). That is, after the voltage according to the expression (1) or (2), which is the D / B voltage detection method using the driving capacitor, is detected (the point P is still in the Hi-z state) The voltage according to Equation (7) or (8) is detected. In this case, &quot; Vpre_com "in Equation (7) or Equation (8) means a detection voltage according to Equation (1) or Equation (2). This embodiment has been described in the embodiment of the area 8 and the area 9. In order to prevent the distortion of the touch signal due to the rising edge or the falling edge of the common voltage or the noise occurring at the common voltage, The touch point should be detected by avoiding the inflection point where the size of the touch point changes.

Fig. 22 shows an embodiment of a method of detecting a touch signal in synchronization with a detected common voltage. Referring to FIG. 22, the " detected common voltage " is the common voltage detected by the common voltage detecting unit 15 in the embodiment of FIG. 17, and "Vg" As a voltage applied to the control terminal, the switching element used for the charging means 12 in the high state is turned on and the switching element used for the charging means 12 in the low state is turned off. "Sel_pretime" determines the high time of Vg. "Vdrv" is the driving voltage applied to the driving capacitor Cdrv in FIG. 11, and defines the time when Vdrv becomes high in synchronization with the falling edge of Vg as "sel_drvdly" do.

The time t1, which is the high section of the common voltage detected in FIG. 22, and the time section of the time t2 that is the low section are displayed differently, but they may be the same, and the time t2 may be longer than t1.

 Region 1 is a region for detecting the touch signal at the rising edge of the common voltage, and Area 2 is the region for detecting the touch signal at the falling edge of the common voltage. The touch is detected by avoiding the edge portion of the common voltage detected in the area 1 or the area 2. To detect the touch, the charging means 12 is first turned on to apply charging voltage to all the capacitors connected to the point P in FIG. 11 To charge the capacitors. As described later, since tens to hundreds of touch pads 10 are connected to the TDI using the sensor signal line 22, the resistance increases when the length of the sensor signal line 22 becomes long. Therefore, it is necessary to vary the charging time according to the position of the touch pad 50 located on the touch screen panel 50. For this reason, "sel_pretime" in FIG. 22 for determining the charging time of the charging means 12 has to be variable and has means for varying it in TDI. For example, "sel_pretime" is a value within a range of 1 ns to 1000 ms , Which is determined by the internal register of TDI.

In one embodiment, 10us is allocated to the register 01, and 100ms may be allocated to the register 0A. This is one embodiment of register allocation, and more charge is allocated on a one-to-one basis in a larger number of registers.

The charging time can be variably determined based on the distance between the touch pad formed in a matrix form and the TDI 30 according to the above-described embodiment, and accurate touch detection can be performed.

 It is preferable to avoid the rising edge or the falling edge, which is the voltage converting portion of the common voltage, when applying the charging voltage in the region 1 or 2. The reason for this is that although the common voltage detected in the embodiment of FIG. 22 is an ideal case and there is no noise, when a common voltage is actually detected for industrial use, a case where noise is applied to the voltage- Therefore, it is preferable to apply the charge voltage from a predetermined time after the common voltage is detected as a means for avoiding this.

FIG. 23 shows an example of a common voltage actually detected, which is not linear in the early part of the rising edge and the falling edge. Thus, when the touch signal is detected in the nonlinear section, the touch signal is distorted. Therefore, in order to avoid such a non-linear region, a charge voltage is applied after a time set to " sen_hi_dly "or " sen_lo_dly & "Sen_hi_dly" is a delay time point synchronized with a point when a common voltage higher than the URL is detected, and "sen_lo_dly" is a delay point synchronized with a point when a common voltage lower than LRL is detected.

At this time, the time for turning on the charging voltage may be made in a partial region of the nonlinear region of the common voltage. If charging is performed in the non-linear region of the common voltage, the voltage fluctuation due to the D / B phenomenon due to the alternation of the common voltage does not occur. If the linear region of the common voltage is outputted at the completion of charging, This is because voltage fluctuation does not occur.

Referring again to FIG. 23, the duration of the nonlinear section in the high section of the common voltage differs from that of the nonlinear section in the low section. In order to avoid the different nonlinear regions in the interval where the common voltage is high and the interval in which the common voltage is high, it is necessary to set "sen_hi_dly", which is a time for avoiding a high section, and "sen_lo_dly", which is a time for avoiding a low section, . The TDI 30 has means for setting these two times, and in one embodiment this means can be determined as a register inside the TDI.

Referring again to FIG. 22, region 2 is a region for generating a signal for detecting a touch signal in synchronization with the falling edge of the common voltage. When the common voltage changes from high to low, it is delayed for a certain time starting from "sen_lo_dly". On the other hand, " Vdrv "in FIG. 22 indicates a state in which the charging means 12 is turned on to set the potential at the point P in FIG. 11 at the charging voltage and then goes from low to high in synchronization with the timing at which the charging means 12 is turned off The touch signal can be detected through Equation 1 or Equation 2 by such a state change as described above.

In the embodiment of the present invention, the change of the voltage generated when the Vdrv changes from low to high is described as an embodiment. However, this is an embodiment only, and the touch signal can be detected even when the change from high to low is performed. The synchronization point at which the level of Vdrv is changed may be a common voltage or a point of time when the charging means 12 is turned on.

In Fig. 22, if the time for applying Vdrv after the charging is completed is long, there is a possibility that the noise is input during the time of waiting for the input of Vdrv to change the potential at the point P in Fig. In order to avoid this, it is necessary to rapidly apply the driving voltage Vdrv, but since the switching element used in the charging means 12 is completely turned off, Vdrv must be applied, so that the time for applying Vdrv can be varied ) So that you can find the right time through testing. Therefore, the TDI 30 has a means for varying the time for applying Vdrv. In one embodiment, the Vdrv application time is set such that when the charging means is turned off by a change in the voltage level of the control voltage Vg input to the on / off control terminal of the charging means 12, And can be selected from about 1 ns to about 100 ms. As an example of this means, a register is used and the first value of the register will have a time of 1 ns and the last value will have 100ms.

Also, as described above, the time point of applying Vdrv may be synchronized with the lower or the lower of Vg, but it may be a common voltage conversion unit, or Vdrv may be applied by a timer or an interrupt of TDI.

When a driving voltage Vdrv is applied, a voltage due to D / B is formed, which is detected by the touch detection unit 14. Since the resistance value of the sensor signal line 22 is different depending on the position of the touch screen panel 50 as described above, the time for which the voltage by the D / B is formed when the Vdrv is applied is determined by the sensor signal line 22 It depends on the resistance value formed. For example, the touch pad 10 farthest from the TDI will have a resistance value of several hundred Kohm, and the resistance of the touch pad 10 adjacent to the TDI will be tens of Kohm. As a result, the touch pad 10 may be made of ITO, IZO, CNT, or the like, which is the entire transparency. Since the sheet resistance of the touch pad 10 is several hundreds of ohms, a touch screen panel The resistance value of several hundred Kohm is derived by calculation when the sensor signal line 22 is formed with a line width of about 50 um at a distance of about 9 cm which is the longest distance of the sensor signal line. Since the time point at which the voltage change due to D / B is completed differs depending on the resistance of the touch pad 10 or the capacitor formed in the sensor signal line 22, the time point at which the voltage is detected after Vdrv is applied must be variable. Therefore, TDI has means for varying the time for detecting the voltage after applying Vdrv.

The &quot; detection start &quot; in Fig. 22 exemplifies this voltage detection point and has a variable width of about 1 ns to about 100 ms in synchronism with the inflection part or Vg of the common voltage. The variable may be a register, and a plurality of times may be mapped to a plurality of registers on a one-to-one basis.

Referring to Equation (1) and Equation (2), the detection voltage by D / B is proportional to (Vh-Vl), which is the voltage fluctuation width of Vdrv. If Vdrv is changed from 0V to 5V, the detection voltage when the contrast is changed from 0V to 2.5V falls to 50% level. Therefore, by appropriately adjusting the voltage amplitude of Vdrv, it is possible to adjust the magnitude of the detection voltage by D / B. This operation may be performed by a power supply included in the TDI 30 or a power supply supplied from outside the TDI 30. [ If the internal power supply of the TDI 30 is used, the size of the Vdrv is changed by changing the register set value included in the TDI.

FIG. 24 shows an embodiment in which the magnitude of Vdrv varies according to the setting of the register included in the TDI. Referring to FIG. 24, when the address 00h of the register is selected, the voltage of Vdrv becomes 2V, and when register address of address 07h is selected, Vdrv becomes 16V.

As described above, the touch detection apparatus according to the above-described embodiment can vary the driving voltage Vdrv and adjust the magnitude of the detection voltage associated with the touch sensitivity.

25 is a configuration diagram showing an embodiment of the touch screen panel of the present invention. FIG. 25 shows an embodiment in which the touch detection means as shown in FIG. 10 or FIG. 11 is applied and the touch pads 10 are arranged in a dot matrix form.

25, the structure of the TDI 30 is shown. The TDI 30 includes a driving unit 31, a touch detection unit 14, a timing control unit 33, a signal processing unit 35, a memory unit 28, a common voltage detection unit 15, And a communication unit 46, and may further include a CPU 40. [ The CPU 40 is a microprocessor having an arithmetic function and may be located outside the TDI 30.

The touch screen panel 50 is formed by patterning the touch pad 10 and the sensor signal line 22. The touch pad 10 is made of ITO, IZO, or CNT (Carbon Nano Tube), which is the entirety of transparency, and is not limited in shape such as a square, circle, triangle, Star shape or flexel configuration. The touch pad 10 and the sensor signal line 22 are formed of the same device. When the touch pad 10 is formed of ITO, the sensor signal line 22 is also formed of ITO. In this method, the touch pad 10 and the sensor signal line 22 can be patterned with a single mask, and the touch screen panel 50 of the present invention can be manufactured with a single layer using a single mask I will.

The touch screen panel 50 of the present invention using a single layer does not pass another touch pad 10 or the sensor signal line 22 to the upper side or the lower side of the touch pad 10 or the sensor signal line 22, The thickness of the touch screen panel 50 is reduced, the transmittance is improved, and the cost is reduced by improving the yield.

Figs. 26A to 26C show various embodiments of the touch pad 10 according to the present invention. 26A to 26C. 26a is a shape in which triangles face each other, 26b is a shape in which arrows are matched with each other, and 26c is a shape in which half-moon is matched with each other. As shown in FIG. 26A, when a plurality of slanted touch pads are opposed to each other, it is possible to extract the touch coordinates using the area relationship between the touch pads 10c and 10d.

For example, when the touching means is located at the center of a quadrangle composed of 10c and 10d, the area information obtained at 10c and the area information obtained at 10d are identical, so that it can be seen that the touch means is located at the center of the quadrangle. It can also be shown that the touch means occupies 20% of the area of 10c and occupies 80% of the area of 10d, and it is located at the upper part of the square, and it can be calculated that it is located about 20% below the upper part. As described above, when the touching means is in contact with a plurality of touch pads 10 adjacent to each other, the position of the touching means can be detected by the area ratio between the touching pads. The combination of the touch pads 10 having the correlation shown in Fig. 26 is one embodiment, and can be formed in various forms such as a combination of a star shape and a combination of a leaf shape.

27 is an embodiment of the touch screen panel 50 shown in FIG. 5 of Korean Patent Laid-Open No. 10-2010-0021112 as a conventional technique as compared with the embodiment of the present invention. 27 differs from FIG. 26A, which is an embodiment of the present invention. The technique of FIG. 27 differs from the embodiment of FIG. 27 in that the sensor signal line 22 does not pass to the left and right of the touch pad (522, 524, 526, 528, ) Are wired only above and below the touch screen panel. This technique narrows the right and left widths of the touch pads (522, 524, 526, 528 of Fig. 27, 10 of Fig. 26A) to enable accurate touch coordinate detection, but limits the number of touch pads. On the other hand, when the touch detection sensitivity is good, the touch signal can be detected even if the sensor signal line 22 is wired to the left and right of the touch pad 10 and the interval of the touch pad is widened as shown in FIG. A larger number of touch pads can be installed, so that the touch coordinates can be detected more precisely.

28 is a technique of wiring the sensor signal line 22 to the top and bottom of the touch pad 10 as an example of the prior art which is compared with the prior art. 28, the sensor signal line 22 of FIG. 28 is disposed on the upper and lower sides of the touch pad 10, the left sensor signal line 22 is collected on the left side of the touch screen panel, and the right sensor signal line 22 is And are all gathered on the right side of the touch screen panel 50. This connection method has disadvantages that since the number of signal lines integrated on the left and right of the touch screen panel 50 increases, the left and right regions of the touch screen panel 50 are widened and the merchantability of the product is lowered. 25, since the sensor signal lines 22 are not integrated on the left and right sides of the touch screen panel 50, the right and left regions of the touch screen panel 50 can be narrowed. Therefore, Can be made into a narrow bezel type, which is advantageous in that the merchantability is increased.

28, since the length of the wires connected to the TDI 30 is considerably long since the touch pad 10 and the sensor signal line 22 are both made of ITO It is impossible to form a transparent conductor. Therefore, the sensor signal lines 22 disposed on the left and right of the touch screen panel 50 are formed of metal-based copper or silver, etc., and an additional process different from the process of patterning the touch pad 10 must be used There is a problem that the manufacturing cost is increased and the yield is lowered.

Referring again to FIG. 25, the driving unit 31 includes the charging unit 12 and the driving capacitor Cdrv as in the embodiment of FIG. There is also a common voltage detection circuit as shown in Fig. 17 or Fig. Referring to Equation (1) and Equation (2), since the magnitude of the detected voltage varies depending on the magnitude of Cdrv, means for changing the magnitude of Cdrv should be provided in the TDI. The larger the Cdrv, the larger the detection voltage, which means that the detection sensitivity is good. However, if the Cdrv becomes too large, the volume of the TDI increases, which causes the price increase of the TDI. In order to adjust the size of the Cdrv, registers are installed in the TDI. The register has a plurality of addresses, and different Cdrv values are mapped to each address. Cdrv corresponding to the value of the selected register is connected to the touch signal detection circuit included in the touch detection unit 14. [

In the embodiment of FIG. 25, the touch pad 10 is composed of 35 pieces of 5 (horizontal) x 7 (vertical) pieces. When the touch pad 10 is positioned at the A / A name of the display device, the A / A is divided into 35 touch areas. This is merely an embodiment, and more than 100 touch pads 10 may be installed on the actual touch screen panel 50. [ If the driving circuit 31 of the TDI 30 has the detection circuit unit 14 as shown in FIG. 11 corresponding to one touch of the touch pad 10, the area of the TDI becomes wider and the price becomes a factor of raising the price. Therefore, a small amount of the detection circuit unit 14 is provided in the driving unit, and the touch signal can be detected by multiplexing the touch pad 10 by the time division method.

For example, the driving unit 31 is provided with one detection circuit unit 14 shown in Fig. The touch signal detection circuit connected to the charging means 12, the detection circuit portion 14 and the capacitors connected thereto is sequentially connected with the touch pads 10 by multiplexing one by one. That is, since there is only one touch signal detection circuit, but the number of the touch pad 10 is 35, a multiplexer having 35 inputs and selecting one of the 35 inputs and connecting it to the detection circuit should be designed.

In another embodiment, the driving unit 31 is provided with a plurality of touch signal detecting circuit units 14. [ However, the number of the touch signal detecting circuit units 14 is smaller than that of the touch pads 10, and in the embodiment, five or seven touch signal detecting circuit units 14 are provided. When five touch pads 10 are provided, it is possible to simultaneously detect the touch signals of the five touch pads 10 in a one-to-one correspondence to the five touch pads 10 installed in the horizontal direction, Touch signal detection is possible. In addition, when seven detection circuit units 14 are used, it is possible to detect seven touch pads 10 in the longitudinal direction for one scan, so that 35 touch pads 10 are scanned five times in the vertical direction, It is possible to detect the signal of

The touch pad 10 is used for detecting a touch signal but also for detecting a common voltage. For example, in FIG. 25, when the touch signal is detected on the touch pad 10 including the first to fifth lines in the first touch pad (slash processing) of the sixth line in the horizontal direction, Since it is not an order of detection, it is connected to the common voltage detecting circuit unit to detect the common voltage. If the touch detection is completed up to the fifth line and the touch pad 10 for detecting the common voltage is detected, the touch pad 10 for which the touch detection has already been completed, The touch pad 10 is used. The signal processing unit 35 controls the MUX of the driving unit to determine whether the touch pad 10 is to be connected to the touch detection circuit categorized in Fig. 11 or to the common voltage detection circuit categorized into Fig. 17, To the driving unit (31). The driving unit 31 connects the touch pad 10 to the touch detection circuit unit or the common voltage detection circuit unit according to a signal received from the signal processing unit 35. [ At this time, one or a plurality of common voltage detecting circuit portions are used, and a plurality of different touch pads 10 are connected to a plurality of common voltage detecting circuit portions and used for detecting a common voltage.

It is preferable that the sensor signal line 22 originating from the touch pad 10 and connected to the TDI 30 should have as low a resistance as possible. 25, the sensor signal line 22 may be connected to the corner of the touch pad 10 at the 5 o'clock position so that the connection path between the touch pad 10 and the TDI can be made the shortest distance. The 5 o'clock direction of the touch pad 10 is a path through which the path of the touch pad 10 and the TDI is minimized. When the TDI 30 is positioned on the upper side in the configuration of the touch pad 10, Will originate near the corner located at 11 or 2 o'clock position of the touch pad 10 and will be connected to the TDI 30.

The parasitic capacitance detected by the resistance of the sensor signal line 22 and the parasitic capacitance detected by the sensor signal line 22 increases as the touch pad 10 moves farther away from the TDI 30. Therefore, And the space between the sensor signal line 22 and the sensor signal line 22 is widened to reduce Cp. That is, according to one embodiment of the present invention, the width of the sensor signal line 22 is set differently based on the distance between the touch pad 10 and the TDI 30, Can be prevented from deteriorating.

The touch detection unit 14 detects the voltage by D / B as described above, amplifies the voltage, and outputs it to the ADC conversion unit 14-5 (or ADC). One or more ADCs 14-5 included in the touch detection unit 14 may be used. As more ADCs 14-5 are used, the time required to convert the detected analog amount of signal to digital is shortened. However, as the number of ADCs 14-5 increases, the consumption current increases and the area of the TDI 30 increases. As a result, the cost increases. Therefore, an appropriate number should be selected considering the report time to the set. The touch detection unit 14 also includes a DAC 14-3. The DAC 14-3 is used as a reference signal applied to the differential amplifier in the configuration of a differential amplifier to be described later and serves to calibrate the voltage detected by each touch pad 10. [

The timing controller 33 serves to generate a plurality of different clocks required in the TDI. For example, a clock is required to operate the CPU 40, and a clock is also required to operate the ADC or the multiplexer of the driving unit 31 sequentially. As described above, there are several kinds of clocks required for each function, and the timing controller 33 generates and supplies the plurality of various clocks.

Since the common voltage detector 15 has been described above, a detailed description thereof will be omitted.

The signal processing unit 35 transfers the ADC value generated by the touch detecting unit 14 to the CPU 40 or the ADC 46 to the outside of the TDI 30 through the I2C or SPI signal line by controlling the communication unit 46, And generates and supplies signals required by all functional elements inside the TDI 30 such as the touch detection unit 35 and the driving unit. The element for each function or the block for each function refers to each function shown in Fig. For example, in the current TDI, nine functional blocks are included, and the CPU 40 is one of them. The signal processing unit 35 stores the ADC value generated by the touch detection unit 14 in the memory unit 28 and performs necessary calculations. For example, the signal processing unit 35 may calculate the touch area due to the touch of the touch pad 10 and the contact means by referring to the ADC value generated by the touch detection unit 14, and may also calculate the ADC value or the calculated area value To calculate touch coordinates. Referring to FIG. 14B, a touch is sensed by 15 touch pads 10 by the finger 25, and a face area of each touch pad 10 is opposite to the finger. In this case, since the touch coordinates are the center of gravity of the area consisting of 15, the area and touch coordinates are different concepts.

The memory unit 28 includes a flash memory, an E2PROM, an SRAM, or a DRAM. Flash memory or E2PROM stores the result or register value of the factory cal. Or the program necessary to operate the CPU (40). If a set of 5x7 touch pads 10 is defined as a frame in FIG. 25, a memory including the detected voltage values of the touch pads 10 included in one frame may be referred to as a frame memory. When a frame is detected several times and an average or a filter is used to detect the touch signal, a plurality of frame memories are required. If a 10-bit or 12-bit or 14-bit ADC is used to detect a touch signal, the frame memory size increases as the ADC resolution increases. Therefore, the first detected value is incremented based on the data stored in the first frame memory If you store only the difference between the values, it will help to reduce the memory size.

On the other hand, the memory unit 28 may also require a line memory. For example, in the embodiment of FIG. 25, when five touch pads 10 or seven vertical touch pads 10 are simultaneously detected, a line memory capable of storing five or seven touch signals is required Do. If a line is scanned a plurality of times and an average is taken using the detected touch data or a filter is used, a plurality of line memories are required. Since such a line memory has a smaller capacity than the frame memory, using line memory rather than using frame memory is more efficient in reducing memory size.

The CPU 40 overlaps the function of the signal processing section 35 a lot. Accordingly, the CPU 40 may not be included in the TDI 30 or may be located outside the TDI 30. [ If the CPU 40 and the signal processing unit 35 are used at the same time, one may not be used.

The CPU can perform most of the functions of the signal processing unit 35 and extract gesture coordinates or perform gestures such as zooming, rotation, and movement, or perform various functions . The function may be "palm rejection" or a Smart grip as described in FIG. In addition, when the GUI object such as a keypad is touched at the same time, only a GUI object (for example, a lot of area is detected) that the user desires The data can be processed in various forms such as recognizing it as an input and used inside the TDI 30 or can be transmitted to the outside using a communication line.

 The program for controlling the CPU 40 is installed in the memory unit 28 and can be replaced with a new program when a modification is made. The new program is implemented by using a communication bus included in the communication unit 46, for example, serial communication such as I2C, SPI, or USB, or parallel communication such as a CPU interface (I / F). The CPU 40 calls a plurality of signal detection values stored in a line memory or a frame memory to obtain an average or a stable value using a filter. The values stored in memory are ADC values or area values.

The communication unit 46 outputs necessary information to the outside of the TDI 30 or inputs information provided outside the TDI 30 into the TDI. Parallel I / F such as serial communication such as I2C or SPI or CPU interface is used for the communication part.

10 to 11, the voltage at the point P is converted into an ADC value by the ADC conversion unit 14-3 of the touch detection unit 14, and is converted into an ADC value by the amplifier 14-2 Amplified.

As amplifiers, various types of amplifiers such as inverting amplifiers, non-inverting amplifiers, differential amplifiers, and instrument amplifiers can be used. Referring to Equation 1 and Equation 2, the detection of the touch signal means that the result of Equation 2 when Ct is added to the denominator of the equation and the result of Equation 1 calculated without Ct To detect the difference between the two. For example, suppose that Equation 1 is always constant and this value is 4V. Equation 2 can not be greater than 4V because Ct is included in the denominator and is always less than or equal to 4V. A differential amplifier can be used to detect a minute difference generated in Equation 1 and Equation 2 due to the difference in Ct, and FIG. 29 shows an embodiment of a differential amplifier to be used in the present invention. It is a matter of course that the differential amplifier of FIG. 29 is an embodiment of the present invention and that the various amplifiers described above can be used.

Referring to FIG. 29, the differential amplifier has two input terminals, and Vp and Vref are input to the respective input terminals. Vp is the potential at the point P in Fig. 11, and Vref is the reference voltage. The differential amplifier can set an amplification gain (gain) by using a resistor or a capacitor, and the output voltage of the differential amplifier is determined according to the equation shown on the right side of FIG. The differential amplifier of Fig. 29 does not represent only one element but functionally indicates that it is a differential amplifier. Therefore, a plurality of amplifiers may be used in the differential amplifier shown in FIG. 29. These amplifiers may be connected to each other in series or in parallel, and Vp or Vref may be connected to the input terminal of another amplifier included in the differential amplifier of FIG. 29 .

Although not shown in FIG. 29, another signal or another reference voltage Vref may be applied. The gain may be set in one amplifier or may be set in a plurality of amplifiers. For example, if the gain is 12, the gain is set to 12 when the gain passes through the amplifier of 12, and the gain of 12 is obtained even if the signal through the amplifier with gain of 4 passes through the amplifier with gain of 3 It is possible. Also, the total gain is 12 even if the amplifier with gain 2 is passed twice and the amplifier with gain 3 is passed once more.

It is preferable that the gain of the differential amplifier according to the embodiment of the present invention has gains of various multiples. Because the magnitude of the voltage detected in Equation 1 or Equation 2 varies depending on the area of the touch pad 10 or the structure of the touch screen panel 50, if the magnitude of the detected voltage is too small, If the amplitude of the detection voltage is too large, the amplification amount should be small. Therefore, the TDI 30 preferably has means for setting the gain. The gain setting can be set in the register or the memory unit (28). The gain can be changed by changing the circuit or controlling the circuit change with reference to the set value.

Vp in FIG. 29 is connected to the differential amplifier through the buffer 14-1 or directly to the differential amplifier.

Vref is generated in the power supply unit 47. [ 29, when the polarity of Vref and Vp connected to the input terminal of the differential amplifier is reversed in contrast to the polarity of Vref and Vp connected to the input terminal of the differential amplifier in the case of Vout outputting the positive polarity, The output is a minus voltage. If the TDI uses only a positive voltage, if the output of the differential amplifier is to be output as a negative voltage, a negative output is not generated in Vout, so that a detection error occurs. Therefore, a measure that does not cause a detection error is required, which will be described later.

Referring to the equation of FIG. 29 and Equation 1 and Equation 2, when Vdrv is changed from low to high and applied to Cdrv, the magnitude of the voltage detected in Equation (1) Is greater than or equal to. Assuming that the result value of Equation 1 is 4V and the result of Equation 2 is 3.8V, the difference between Equation 1 and Equation 2 is 0.2V. Therefore, when Vref is set to 4 V and the gain is set to 10, Vout in FIG. 29 is set to Vout = {10 * (4-4) when Vp follows Equation 1 (i.e., } = 0 and 0 V is output. When Vp follows Equation (2) (that is, when it is touched), Vout = {10 * (4-3.8)} = 2V. Thus, according to the magnitude of Vref, it is possible to extract only differences between Equation 1 and Equation 2 in the differential amplifier. At this time, the reference voltage Vref is set to be larger or smaller by a predetermined amount based on the result of Equation (1), which is equal to 4V which is the result of Equation (1). For example, it is preferable that Vref is larger or smaller than 1V in comparison with the result of Equation (1).

On the other hand, since most of the elements used in the differential amplifier of FIG. 29 are OPAMPs, when a single power having a positive polarity is used for the OPAMP, the potential of the ground is 0 V (zero volt). In this environment, when Vout is 0V, when OPAMP is not a rail-to-rail type, when 0V is to be outputted, a voltage higher than 0V is outputted and a signal detection error occurs. In order to solve this problem, it is preferable that a potential higher than 0 V is used as the ground potential used in the OPAMP.

The ground potential is, in one embodiment, a voltage that is about 1/2 of the OPAMP Bias power supply is preferably formed at the ground potential. For example, if a 5V supply is used as the bias voltage for the OPAMP, the ground potential of the OPAMP will be 2.5V. In this environment, Vout means ground potential, meaning that the output of Vout is 2.5 V, which is higher than 0 V, so that the signal is normally output even when the ground potential is output.

It is preferable that Vref is equal to or larger than the detection value by Expression (1) describing the detection voltage when no touch is made. 29, when Vref is smaller than Vp, Vout must output a negative voltage. When the TDI 30 uses only a positive power source, no negative output is generated at Vout. Therefore, Distortion occurs. Vref should be at least equal to or greater than the voltage detected at Vp when not touched. Since the magnitude of Vref varies according to the size of the touch pad 10 and the structure of the touch screen panel 50, To be set by the program or the register using the DAC rather than by the DAC. However, when the DAC can not be used, a plurality of reference voltages are generated and connected to the differential amplifier.

Another reason to use DACs or multiple reference voltages for differential amplifiers to precisely generate voltages of various sizes is as follows. Referring to FIG. 25, there are other sensor signal lines 22 on the left and right of the sensor signal line 22, or the touch pad 10 exists. In this structure, the capacitance according to the equation of FIG. 7 is formed between the sensor signal line 22 and the sensor signal line 22 and the touch pad 10, and according to the formula, the larger the distance between the sensor signal lines 22 and the touch pad 10, the larger the capacitance becomes. When the sensor signal line 22 and the touch pad 10 are adjacent to each other, the larger the number of the touch pads 10 adjacent to the sensor signal line 22, the larger the capacitance becomes. Also, a capacitance is generated in a region where the sensor signal line 22 is connected to the TDI 30, which is variable depending on materials used for connection, process conditions, connection area, and the like. Also, in the TDI 30, the capacitance of the sensor signal line 22 is generated by the interference with the signal lines arranged in the top, bottom, left, and right in the layout process. All of these capacitances are parasitic capacitors that are inevitably generated in manufacturing the touch screen panel 50 and the TDI 30, and are described as Cp in Equation 1 or Equation 2.

Since the parasitic capacitor Cp varies depending on the sensor signal line 22, the process conditions, or the layout inside the TDI 30, the parasitic capacitors of different sizes are present in each of the touch pads 10 Modeling can be done. According to this modeling, since the detection voltages represented by Equation 1, Equation 2, Equation 7 or Equation 8 are different from each other for each touch pad 10, Vout Are different from one touch pad 10 to another.

The meaning of detecting the touch signal as described above is to obtain the voltage difference defined by Equation 1 and Equation 2. The distribution region in which the voltage difference between Equation 1 and Equation 2 exists is wide The higher the gain, the lower the gain of the amplifier. For example, assuming that the voltage difference between Equation 1 and Equation 2 is 0.2 V in the ideal condition and can be amplified to 2 V by the combination with the ADC, a gain of 10 times can be set. However, assuming that the voltage difference between Equation 1 and Equation 2 is within a range from 0.1V to 0.4V, the gain is inevitably set at 0.4V, I can not help it. As a result, in the case of the touch pad 10 having a signal difference of 0.1 V, the sensitivity is not good because only 0.5 V is amplified. Therefore, in order to increase the amplification factor, a method of adjusting the Vref of FIG. 29 and narrowing the distribution area of Vout is used. One of the easiest ways to achieve this is to adjust the Vref of FIG. 29 so that the output voltage of Vout becomes the ground potential when no touch is made. If Vout is higher than the ground voltage, the Vref voltage may be lowered. If the Vout is lower than the ground voltage, the Vref voltage may be increased. This process is called calibration (or calibration).

30 is an embodiment in which an ADC conversion unit is connected to an amplifier output unit. The correction process will be described with reference to FIG.

First, the correction must be performed in the state that the touch is not performed. The conditions under which a certain state of non-touch can be assured is the manufacturing or shipping process in which the touch screen panel 50 of the present invention or the product to which such touch screen panel 50 is applied is under the control of the producer. Therefore, correction in a state not yet in use condition by the user is referred to as " factory calibration, "or &quot; factory calibration, &quot; fac. Cal can be defined as a process of finding a DAC value as a reference voltage such that the value output from the amplifier of FIG. 30 is a constant value reflecting the Cp inherent to each touch pad 10 without being touched. Since the capacitances of the sensing touch pads 10 are different from each other, the value of the DAC will be different for each sensing touch pad 10. Since the calibration is completed for each detection pad and different DAC values are obtained for each detection pad and the same input signal must be applied to the amplifier corresponding to each touch touch pad 10 in the step of detecting the touch signal, It must be stored in a non-volatile memory, such as Flash memory or E2PROM, and it is called whenever it is used. The &quot; expected value &quot; or &quot; target value &quot; in the calibration process is the value of the ADC converter output (or used in the same sense as the "ADC output") value of FIG. For example, if the expected value is 0V, which is the ground potential, the ADC output would be 0 in the ideal case. Or 10-bit resolution, if the maximum output voltage of the amplifier 14-2 is predefined at 5V, and if the output voltage of the amplifier 14-2 is 2.5V, (14-3) will be 512 codes. Under this assumption, the output value of the ADC converter is 50 code, which is a good target value.

It is not preferable that the target value output from the ADC conversion unit is 0 code. In order to start the calibration at first, the DAC of FIG. 30 must be applied with an arbitrary value. If the DAC is lower than Vp and the output of the amplifier is negative, the output of the ADC is 0 code. Because it is difficult to distinguish whether 0 code is output even if the output is 0 or less. Therefore, the target value to be output from the ADC converter should be set somewhat higher than 0 code. For example, the target value should be a value greater than or equal to 0 in ADC code, and a 50, 100, or 200 code is a good target value. However, if the target value is set too high, the fluctuation of the ADC code when the touch occurs will be narrowed, so the lower the target value, the better.

First fac. the DAC value applied to the amplifier at the time of cal must be approximated to the DAC value at the time of correction. The approximate value of such a DAC can be obtained by calculation. Referring to the equation of FIG. 29 when Vp is larger than the DAC value, the output of the amplifier 14-2 should be a negative value. The ADC code corresponding to this negative value should also output a negative value, but when the ADC can not output a negative value, it outputs the lowest value 0 (zero). At this time, there is a need for a means to check whether the zero value is substantially zero or less. As one of such means, a means called " Under Flag "is used.

The under flag is a signal that occurs when the ADC output value is 0 (zero). The under flag is generated in the touch detection unit 14, the signal processing unit 35, or the CPU 40. [ The signal processing unit 35 or the CPU 40 extracts a voltage higher than the currently applied DAC voltage among the plurality of voltages of the DAC included in the touch detection unit 14 and outputs the extracted voltage to the amplifier 14- 2). If the UDF continues to be generated, a higher voltage DAC value is applied, and at some point, the UDF is not generated and the target value is output.

FAC to set target value. The process of implementing CAL is as follows. Assuming that the target value is 100 as the ADC code, the voltage value output from the DAC to be initially applied is an expected value that the ADC code 100 can be output, which is applied to the amplifier 14-2. If the DAC output with the first applied voltage value is called DAC (init), the DAC (init) causes the output of the ADC to be higher or lower than the target value of 100 codes. Or UDF may occur. If the code output from the ADC is higher than 100 code, a DAC output of a lower voltage than the DAC (init) must be applied to the amplifier. If the code output from the ADC is lower than 100 codes, The output should be applied to the amplifier. The process of finding a new DAC may be performed through a trial and error method, but this takes a lot of time. Therefore, it is preferable to apply a DAC value derived by calculation in a single time, since correction time can be deduced.

Referring to FIGS. 29 and 30, the ADC (init), which is the output value of the ADC in the uncorrected state output by the first DAC (init), is defined as Equation 10 and is calculated by DAC (cal) The target value ADC (target) is defined as < EMI ID = 11.0 >

&Lt; Eq. 10 &

&Quot; (11) &quot;

According to the relationship between Equation 10 and Equation 11, DAC (cal)

의 관계를 가지므로 목표값을 출력하기 위한 DAC(cal) 값은 계산에 의해 간단히 연산할 수 있는 값이다. 따라서 시행착오법에 의해 목표값을 찾는 것보다 신호처리부(35)나 CPU(40)에서 연산을 통하여 목표값을 출력하기 위한 DAC값을 연산하고 이를 증폭기(14-2)에 인가하면 짧은 시간안에 터치패드(10)를 보정하는 것이 가능하게 된다. 한편, 10bit의 DAC를 사용한다고 가정하고 출력전압의 범위가 0V에서 5V라고 가정하면, DAC에 0(zero) code를 인가하면 0V가 DAC에서 출력되고, DAC에 512 code를 입력하면 2.5V가 DAC에서 출력될 것이며, DAC에 1023 code를 입력하면 5V가 DAC에서 출력될 것이다. 이와 같은 DAC나 ADC의 입출력관계는 이 분야의 당업자가 쉽게 알수 있으므로, DAC나 ADC의 입출력에 연관된 상세한 신호흐름을 통해 명세서를 설명하지는 않았으며 단지 DAC나 ADC의 출력값만을 인용하여 명세서를 설명하였다.

The DAC (cal) value for outputting the target value is a value that can be easily calculated by calculation. Therefore, rather than searching the target value by the trial and error method, the DAC value for outputting the target value is calculated by the signal processing unit 35 or the CPU 40 and applied to the amplifier 14-2, It becomes possible to correct the touch pad 10. Assuming a 10-bit DAC is used, assuming that the output voltage range is from 0V to 5V, if 0 (zero) code is applied to the DAC, 0V is output from the DAC. If 512 codes are input to the DAC, If you enter 1023 code in the DAC, 5V will be output from the DAC. Since the input / output relationship of the DAC and the ADC is easily known to those skilled in the art, the detailed description of the DAC or the input / output of the ADC is not described in detail, and only the output of the DAC or the ADC is described.

FIG. cal flow chart. Referring to FIG. fac. In step F30a, which is the first step of cal, the arbitrary DAC (init) value is applied to the amplifier. In step F30d, the target value is called from the memory (F30b) to calculate the DAC (cal) (F30c). The DAC (cal) value obtained through the operation is stored in the non-volatile memory included in the memory unit 28 (F30e), and the stored value is the voltage that is the output value of DAC (cal) or the DAC The input code of the DAC (cal) is stored. Then, when a touch is detected by scanning the touch pads 10 of the touch screen panel 50 as shown in FIG. 25 one by one or a plurality of times, a voltage which is a unique DAC (cal) value corresponding to an arbitrary touch pad 10 is arbitrary And is applied to the amplifier 14-2 as Vp generated by the touch pad 10 of FIG.

fac. cal may be performed according to a scanning method for touch detection of the touch pad 10 formed on the touch screen panel 50 of FIG. That is, if a scan method for touch detection of the touch pad 10 individually scans one touch pad 10, fac. cal is also performed for one touch pad 10 at a time and touch detection is performed for a plurality of touch pads 10 at one time. cal are also performed for the same number of touch pads 10 in one run. This is because, if the method of scanning the touch pad 10 is changed in the calibration process, the mux used in the touch detection process can not be used and the mux having input and output of different sizes must be used. The cost increases and the operation of the cpu 40 and the signal processing unit 35, which processes the signal, increases and becomes complicated.

Using the DAC described above, fac. the touch detection apparatus according to the embodiment of the present invention reduces the variation of the touch detection voltage caused by the position of the touch pad 10 and the characteristics of the parasitic capacitance to provide accurate touch detection.

fac. After the calibration is completed, the product to which the touch screen panel 50 of the present invention is applied is sold to a user and exposed to various use environments. For example, a change in temperature occurs and time elapses. The characteristics of the touch pad 10 and the TDI 30 formed on the touch screen panel 50 may also change with respect to such environmental changes. For example, the resistance of the sensor signal line 22 can be changed with respect to a change in temperature, and the Cp value can also be changed. Also, if the protective layer 24 for protecting the touch pad 10 is worn as time elapses, a change in d in Equation (3) may occur, resulting in a change in sensitivity. Real-time calibration (RTC) is used to extract the touch area or touch coordinates by reflecting such changes in real time.

Many values are stored in the memory unit 28 in order to calculate the touch area or the touch coordinates. For example, in order to calculate the touch area or the touch coordinates of an arbitrary touch pad, the voltage detected in accordance with Equation 1 in the touch pad, that is, the non-touch voltage is converted by the ADC conversion unit 14-3 ) And stored in the memory, the charge voltage Vpre is also stored in the memory, and the Vdrv and Cdrv values are also stored in the memory. This is because Vpre, Vdrv, or Cdrv can be applied to different touchpads at different sizes. According to Equation (1) or (2), when Cp is too large for a certain touch pad (10), the voltage detected by D / B is increased by increasing Vdrv or Cdrv, Can be improved.

If the values written in the memory are used in real time without correcting them, an error may occur in touch detection. For example, the voltage detected at the time of non-touch is a value actually detected in accordance with the theory of Equation (1). The analog voltage output from the amplifier 14-2 is converted into a digital value by the ADC converting unit 14-3 and a difference between the analog voltage output from the amplifier 14-2 and the ADC value detected upon touching according to Equation 2 is detected to calculate a touch area Or touch coordinates are extracted. In this case, when the non-touch voltage according to Equation 1 is stored in the memory and the voltage and the difference according to Equation 2 detected in real time are detected using this value, The values stored in the memory are fac. cal, it can not reflect the changed characteristics due to environmental factors, so detection error may occur. Therefore, the values stored in the memory must also be restored by reflecting the changed characteristics through the RTC.

To this end, the memory area of the memory unit 28, which stores the corrected values, is preferably divided into two. If fac. If calibration is required in addition to cal or RTC, the memory area must be further isolated.

First, fac. Considering only CAL and RTC, fac is divided into two parts. cal, and the values detected in the RTC process or the values extracted in the calculation process are stored on the other side of the memory area. In touch detection process, fac. You may also need to decide whether to use cal data or RTC data. This is because, in a noisy environment, data stored in the memory through the RTC are likely to be noise-affected values. because it can lead to more severe detection errors than using data obtained through cal. If the CPU 40 or the signal processing unit 35 has a means for detecting the magnitude of the noise, It is possible to decide whether to use cal data or RTC data.

The CPU 40 and the signal processing unit 35 can detect the magnitude of the noise using the value of the ADC conversion unit 14-3. When a touch signal is detected by sequentially scanning a single touch pad 10 or touch pads 10 included in a group in a longitudinal direction or a horizontal direction, And filtering is performed to extract desired data. This technique is to remove the noise contained in the detected voltage and to extract a more stable signal. If 100 times are scanned for an arbitrary touch pad 10 and the detected values are stored in the memory every scan, a signal band of the detected signal for 100 times will be formed. For example, a bandwidth of 2V to 4V may be formed and a voltage of 1V to 5V may be formed. For these two bandwidths, the center value is equal to 3V, but the first bandwidth is 2V (4V-2V) and the second bandwidth is 4V (5V-1V). Therefore, in the case of a touch signal generating a bandwidth of 4V, it can be expected that the noise is larger than the bandwidth of 2V. Using this technique, the TDI 30 can check the size of the noise using the output of the ADC converting unit 14-3, so that the TDI 30 can detect the fac size stored in the memory according to the size of the noise. You can decide whether to use cal data or RTC data. Taking memory data differently according to the magnitude of the noise is one embodiment, and the TDI 30 can determine which data to use under given conditions. This determination means may be implemented by a program in the TDI 30 or by a register.

Preferably, the RTC is performed in a non-touch state. For example, when a user performs a call or other operation using a mobile phone using the touch screen panel 50 of the present invention, the RTC should be executed when there is no touch input after completion of a call or other operation. The basic idea of the correction is to find the DAC where the ADC value becomes the target value when the touch is not detected, store the found value in the memory, and use the DAC value when the touch signal of the touch pad 10 is detected. Therefore, if the touch is corrected, a touch detection error occurs.

In order to enforce RTC, it is important to distinguish whether or not a touch is made at the time of the RTC.

The following is an embodiment for judging whether or not to touch. At the time of the first RTC implementation, fac. You should use cal data. fac. The ADC values detected using cal data are between 0 and 1023 codes in 10 bit resolution. The CPU 40 and the signal processing unit 35 can calculate the touch area using the ADC value and the area is also within a certain range as in the ADC. Accordingly, the extracted ADC value or the calculated area reacts with the contact area between the touch pad 10 and the touch means such as the finger 25, and increases or decreases linearly or non-linearly (in this specification, the contact area The ADC value increases linearly between 0 and 1023 codes in proportion to the area of the touch, so the ADC value when no touch is equal to the above-mentioned &quot; target value &quot; As the touch area increases, the ADC value or area value increases. In such a situation, it is possible to determine whether or not the touch is made by setting a threshold value. If the ADC value or the area exceeds 300, the threshold value is determined as 300 if it is determined that the touch is made. Therefore, when the ADC value or area is detected as 300 or more, it can be judged as a touch. It is more convenient to refer to a group of touch pads 10 distributed over a plurality of adjacent large areas rather than considering the ADC or area value of one touch pad 10 when determining whether or not the touch is made. A Gaussian curve is formed when the touch means such as the finger 25 touches the plurality of touch pads 10. The TDI 30 may determine that the touch is a touch when a normal Gaussian curve is detected, and may determine that it is in a non-touch state if the Gaussian curve is not detected. If the Gaussian curve is detected even if the threshold value is 300 or less, it is determined that the RTC is not performed if it is judged that a weak touch occurs.

RTC is fac. The process is the same as for cal. (CAL) value for outputting a previously input target value, and stores the extracted value in a memory, which has a unique value for each touch pad 10. The DAC output value corresponding to the touch pad 10 is connected to the amplifier.

The TDI 30 includes fac. cal data to determine whether to detect a touch or RTC data to detect a touch. It is normally set to a register and may be located in memory or a program. When set to a register, the RTC or fac. Take the cal data. The change of the bit can be determined automatically in the TDI 30 and can be changed automatically by the user.

According to the foregoing description, when the touch is made, the RTC should not be executed, but the detected ADC value or the area of the area value may be referred to in order to determine whether or not the RTC is proceeding.

 FIG. 32 shows an embodiment of the present invention relating to setting the trial area of the RTC. Referring to Fig. 32, the peak of the square wave in Fig. 32 is the voltage due to D / B detected by Equation (1). This level is the level at the time of non-touch, and when the voltage at the moment when Vdrv changes from low to high when touching is applied to Cdrv, the detected voltage by touch defined in Equation (2) Is formed lower than the voltage according to Equation (1), it is formed lower than the voltage at the high point in Fig. In the above description, it is determined whether or not the touch is made by the threshold value, and the threshold value is set at the boundary between the area 2 and the area 3. [

On the other hand, area 1 and area 2 are set around the level at the time of no touch. If the value of Cp decreases as the environment or time elapses, the "No Touch Level" will be raised. Thus, according to the magnitude of the values contained in the numerator or numerator of the formula 1 or 2, the No touch hour level will be changed upward or downward.

The &quot; no touch time level &quot; cal, it is possible to say that it is a value that has been changed as time elapses. Therefore, the area 1 and the area 2 which change to the upper and lower sides based on this value are fac. It can be considered that the target value due to cal has changed.

At this time, the area 1 in FIG. 32 is an area in which the RTC is unnecessary. Typically, the manufacturers' specifications and shipment reports of the touch screen panel 50 of the present invention include an item for checking touch sensitivity, and the touch sensitivity is specified as an error range. Therefore, area 1 is fac. the result of cal is changed by a predetermined amount to cause an error but does not affect the touch sensitivity.

However, region 2 is the range of regions that affect touch sensitivity, and Region 2 should be the RTC. As described above, the value or area value of the ADC changes linearly or nonlinearly according to the size of the touch, so it is possible to distinguish the region 1 and the region 2 by calculation. Area 2 is the area where error occurs when the touch area is detected without correction, and the error range is out of the range of shipment report.

Next, the signal processing of the touch detection method using the D / B phenomenon of the present invention will be described.

33 is a diagram showing a conventional touch detection circuit.

The conventional capacitive type TDI 30 collects the detection signal generated by the touch detection unit so many times, integrates the collected signal, amplifies the collected signal, and uses the amplified signal for touch detection. 33 is a diagram related to a "Basic Circuit Model" of the QT60xx5B series shown in Fig. 1-5 of Application Note R1.06 of QT60xx5B of "QUANTUM" company as one embodiment of touch signal detection of the conventional capacitance type. 33, the voltage level of "Amp Out" is rising in synchronization with the switching of "Xn." In other words, the voltage level of "Amp Out" is increased in synchronization with the switching of "Xn" The voltage of Cs or Ca gradually increases in proportion to the amount of charge Q due to the classical expression that charge accumulates in Cs or Ca and accumulation amount increases. The voltage due to the accumulated charge is still amplified at the amplifier "Amp" because the voltage level is still low, and these signals are displayed at the lower right of FIG. 33. In this conventional touch signal detection system, Quot; X electrode &quot;, which is a touch pad in the X-axis direction, needs to be switched several times at a high speed in order to increase the detection accuracy, And the resistance of the sensor signal line 22 connected to the "Y electrode" which is the touch pad in the Y-axis direction must be low. This is because, when the resistance of the sensor signal line 22 is increased, the signal is delayed due to the action of the resistor connected to the sensor signal line, so that high-speed signal detection is impossible.

The conventional method limits the value of this resistance to about 20 kohm. In order to apply such a low resistance to the sensor signal line 22, it is impossible to configure the sensor signal line 22 made of a transparent conductive material such as ITO or CNT according to the embodiment of the present invention, Should be used as sensor signal lines. Since the metal-based sensor signal line 22 such as copper or silver (Ag) is visible as being impermeable, it can be seen when the wiring is formed in the active area of the display device as shown in Fig. 25 of the embodiment of the present invention It can not be routed due to problems, and should be installed in the invisible area (or Black Metrix, hereinafter referred to as BM), which is the left and right area of A / A. As a result, there arises a problem that the bezel of the product to which the touch screen panel 50 is applied is widened, and the value of the product is deteriorated. Another problem with conventional products is that the driving device (X drive) must switch at a high speed in order to secure a signal, and therefore there is a high probability of causing an EMS problem.

Also, as can be seen from the equation, the voltage detected in the conventional embodiment as shown in FIG. 33 is sensitive to the change amount of Cs or Ca, which is the capacitance value of the capacitor C. Therefore, there is a problem that calibrations must be performed from time to time to compensate for such problems.

However, referring to FIG. 11, which is an embodiment of the present invention, the conventional method is signal detection by switching multiple times (multi times), whereas in the present invention, a signal is detected by switching at a single time. The reason for this is that the touch screen panel 50 of the present invention must apply a charging signal every time it detects touch or not, so that the initial voltage at point P in FIG. 11 (charging voltage before driving voltage is applied) The voltage level becomes the potential level and the detection can not be performed a plurality of times. Further, since the magnitude of the detection voltage can be adjusted by using the magnitudes of Vdrv, Cdrv, Vh, or Vl as in Equation 1 or Equation 2, if the magnitude of the detected voltage is low, This is because the detection voltage can be increased.

 Therefore, in order to detect the touch signal of the touch screen panel 50 of the present invention, the switching speed for applying Vdrv may be slow, so that the resistance value of the sensor signal line 22 connected to the touch pad 10 may be high.

Assuming that the sensor signal line 22 according to the present invention achieves the same touch detection speed as that of the previous embodiment, if the resistance value of the sensor signal line 22 is 100 You can raise it. Also, since the touch is detected only by one switching, the EMS problem is also significantly reduced compared to the conventional method. Referring to Equation 1 and Equation 2, when the capacitors are present in the numerator and denominator and the value of Cdrv is significantly larger than that of the other capacitors, a change occurs in the values of the capacitors connected to Cdrv or other Cdrv The potential at the point P does not vary greatly.

A further advantage of the present invention is that many capacitors connected to the P point of Fig. For example, even if the sensor signal line 22 is opened after the voltage detection by D / B is completed, the detected voltage is stored in Cdrv, Cvcom or Cp, so that the touch signal calculation is not hindered. As will be described later, by using such a function, it is possible to detect a touch signal which is not affected by noise.

According to the embodiment of the present invention described above, the touch detection can be performed substantially in a single time, so that it is unnecessary to drive at a high frequency, so that it is resistant to noise and accurate touch detection is possible even in a high resistance.

FIG. 34 exemplifies a TFT substrate configuration of an LCD in a transverse electric field mode, and shows a TFT substrate configuration of an IPS mode (In Plane Swithing Mode) which is a transverse electric field mode. Unlike the above-described embodiment, the common electrode 220 is not formed in the color filter 215 of the LCD but only in a part of the area of the TFT substrate 205 in the transverse electric field mode LCD. Referring to FIG. 34, the LCD in the transverse electric field mode will be briefly described as follows.

33, a gate line 242 and a data line 244 are vertically and horizontally arranged on the TFT substrate 205, and a region partitioned by the gate line 242 and the data line 244 is connected to a pixel ). A TFT 250 for switching an image signal is provided in the pixel. The gate electrode 251 of the TFT 250 is connected to the gate line 242 to receive a scan signal and the source electrode 253 and the drain electrode 255 are connected to the data line 244 and the pixel electrode line 248, Respectively. A semiconductor layer 257 of the TFT 250 forms a channel between the source electrode 253 and the drain electrode 255 to apply an image signal to the liquid crystal layer. In the pixel, a common electrode line 246 is formed in parallel with the pixel electrode line 248 as shown in the figure.

When an image signal is applied to the pixel electrode line 248 by the operation of the TFT 250, a substantially parallel transverse electric field is generated between the common electrode line 246 and the pixel electrode line 248 And the liquid crystal molecules move in a plane. Incidentally, as shown in the figure, the common electrode line 246 is formed only in a partial area of the TFT substrate 205. 25 is positioned on the upper surface of the LCD fabricated in the transverse electric field mode or when the touch pad 10 is patterned on the upper surface of the color filter 215 of the LCD, The capacitance of the Cvcom formed between the common electrode line 246 and the common electrode line 246 is formed smaller than the case where the common electrode line 246 is formed in the entire region of the TFT substrate 205.

The LCD in the transverse electric field mode is vulnerable to external ESD because there is no common electrode formed in the entire color filter 215. Therefore, as shown in FIG. 35, ITO, ATO, or CNT, which is a transparent conductive material, is applied to the upper surface of the color filter 215 in a full area painting manner and then connected to a predetermined DC potential. Normally, do. The layer connected to the ground potential and applied to the upper surface of the color filter 215 in the LCD in the transverse electric field mode is referred to as " Back Ground &quot;.

A method in which the present invention can be used in the transverse mode will be described with reference to FIGS. 36 to 37 as follows.

FIG. 36 is a cross-sectional view of the present invention applied to a transverse electric field mode LCD substrate, and FIG. 37 is a front view of the present invention applied to a transverse electric field mode LCD substrate. 36 to 37 illustrate an embodiment in which the touch pad 10 of the present invention is patterned on the color filter 215 of the LCD (hereinafter referred to as on-cell touch). The touch pad 10 is installed inside or outside the A / A 90 of the LCD. The LCD panel 200 has a non-visible region 92 in which no image is displayed, and the touch pad 10 of the present invention may also be provided. The touch pads 10 are connected to the TDI 30 by using a flexible circuit board 96 such as a COF or an FPC.

In this configuration, the touch pads 10 other than the touch pad 10 in which the touch signal detection is in progress should be connected to the ground. Here, the ground is 0V or a DC voltage having a predetermined potential.

38 shows an embodiment of the present invention in which the touch pad 10 is used as a back ground. Referring to FIG. 38, the touch pad 10 is connected to the switch portion 16 of the touch detection circuit, so that the touch pad 10 has three states. The first state is a state in which the touch pad 10 is not connected to the switching portion, and the second state is a case where the touch pad 10 is connected to the switching portion and connected to the ground potential at one side of the switching portion. And the pad 10 is connected to the touch detection unit 14 connected to one side of the switching unit.

In this configuration, all of the touch pads 10b other than the touch pad 10a that detects touch, that is, the touch pads that do not detect touch, are all connected to the ground. Therefore, all the touch pads except for the touch pad 10 which is detecting the touch in FIGS. 36 to 37 are connected to the ground potential, so that the touch pad 10 can serve as a back ground.

Also, since the charging voltage by the Vpre is applied to the touch pad 10 for detecting the touch for a predetermined period of time, a discharging path by the charging means 12 is formed, so that noise such as ESD is transmitted to the outside of the touch screen panel 50 It is possible to perform a back ground function. Therefore, both the touch pad 10a that is detecting a touch and the touch pad 10b that does not detect a touch can play a role of a back ground.

In the embodiment of FIG. 37, one touch pad 10 is detected. However, all of the groups of touch pads 10 in the horizontal direction or all groups of the touch pads 10 in the vertical direction of FIG. Or a method in which a plurality of groups of touch pads 10 detect a touch or detect a touch at random in a specific area is possible. At this time, the touch pads 10 other than the touch pad 10 which is detecting the touch should be connected to the ground by the switching portion.

In the embodiment of FIG. 38, if the signal detecting operation of the touch pad 10a detecting the touch signal is completed, the completed touch pad 10a is connected to the ground by the operation of the switch. Thereafter, the touch pad 10 is disconnected from the ground according to the determined sequence number, and newly connected to the touch signal detecting unit 14 to detect the touch signal. When a plurality of detection circuits as shown in Fig. 38 are used, when the touch pad 10 is formed vertically and horizontally as shown in Fig. 37, the longitudinal direction touch pad 10 and the lateral direction touch pads 10 are sequentially scanned It is possible to detect the touch signal more quickly than to scan the individual touch pad 10 since the touch is detected and connected to the ground after completion.

Referring back to FIG. 37, since the upper and lower areas of the touch pad 10 are empty, noise such as ESD is applied to the LCD to form an electric field in the liquid crystal of the display device under the empty space, A malfunction may occur. In addition, in a region where a plurality of sensor signal lines 22 are provided to the left and right of the touch pad 10, a space exists on the left and right of the signal line, so that image quality due to noise such as ESD may occur through such space.

Fig. 39 relates to the layout of the sensor signal line 22 as an embodiment of the present invention for solving such a problem.

The LCD is made up of dots 275 consisting of three pixels, Red / Green / Blue. In the present invention, individual regions of red, green, and blue are defined as pixels (picture elements). Referring again to FIG. 39, when there is no sensor signal line 22 between the touch pad 10g and the touch pad 10h in FIG. 39, the touch pad 10g and 10h must be narrower than the pixel. Therefore, even if noise is applied to a narrow area between the touch pads 10g and 10h, it is discharged to the outside by the ground potential connected to the upper and lower touch pads 10g and 10h, so that the operation of the pixel is not affected.

In addition, the space between the sensor signal lines 22 should be narrower than the pixel. Referring to the sensor signal line 22a and the sensor signal line 22b, since the space between the two signal lines is narrower than the width of the pixel, even if noise such as ESD is applied, the sensor signal line 22 disposed in the pixel area and connected to the ground So that the image quality in the pixel does not occur.

Referring to FIG. 25 and FIG. 37, a space is also formed between the touch detection pattern 10 and the sensor signal line 22, and the area of the space is increased as the distance from the TDI 30 is increased. In such a space, a transparent conductive material such as ITO used for forming the touch pad 10 may not be printed and may be conspicuous, which may cause display quality defects and may cause image quality defects due to noise such as ESD . Therefore, it is necessary to take measures to improve the visibility and to prevent the image quality defect in such a space.

40A to 40C are views for solving the above problems by providing a filled area or an additional area in a space formed between the touch pad 10 and the sensor signal line 22. Referring to Figs. 40A to 40C, the empty space is filled with the space filling portion 11. Fig. The space filling portion 11 may be made of the same material as that used for the touch pad 10 and may be fill processed (completely filled with no open space) or formed in a mesh structure. 40A, the space charging unit 11 may extend from the touch pad 10 or may be connected to the sensor signal line 22 as shown in FIG. 40B and may be connected to the sensor signal line 22 or the touch pad 10, It is possible to maintain the floating state without being connected to the ground.

On the other hand, in the embodiment as shown in FIG. 41, it is assumed that a conductor 26 such as a water droplet, a sweat, or a metal is placed between the touch pad 10a which is detecting the touch and the touch pad 10b which is connected to the ground potential. (This conductor 26 is not in direct contact with the touch pad 10 but lies on the upper surface of the protective layer 24 as shown in Figs. 12 and 13). As shown in FIG. 41, this forms a movement path of charge on the touch pad 10a during touch detection, and charges Ct. 12 and 13, Ct is formed by the equation of FIG. 7 between the touch pad 10 and the protection layer, and the capacitance of Ct is determined according to the contact area between the touch pad 10 and the conductor do. Since the conductor 26 of FIG. 41 is in touch with the touch pad 10b connected to the ground, one side of the touch capacitor Ct1 of the touch pad 10a which is detecting the touch is connected to the ground and the grounded touch pad 10b A path of movement of the charge is formed. Since the touch capacitor Ct2 is formed in the touch pad 10b connected to the ground, one side of Ct1 has a path connected to the ground through Ct2. Therefore, since the Ct1 is charged when the touch pad 10a for detecting a touch is charged through the charging means 12, the touch is recognized as if the touch has occurred even if the touch is not performed by the finger 25 of the body by Equation (2) .

In order to prevent such a problem, a touch pad 10b (hereinafter abbreviated as NSP) connected to a ground potential without touch detection is connected to a touch pad 10a (hereinafter, abbreviated as a sensing pad, SP) When the touch signal is detected, the connection with the connected ground potential is released and the floating state is maintained.

According to the configuration of the present invention described above, since the touch pad has three states of a ground state, a floating state, and a connection state, it is possible to support a liquid crystal display device of a transverse electric field mode, Can be prevented. If the display device is not in the transverse electric field mode, the touch pad may not select the ground state.

The details will be described with reference to FIG. FIG. 42 shows waveforms except for a portion synchronized with the common voltage in the embodiment of FIG. 22, and is an embodiment of the present invention relating to the open (open or open) of the NSP.

42 is a section for charging the capacitors connected to the touch detecting section 14 and for inducing a voltage by the D / B phenomenon. 41, when the capacitors connected to the touch detecting section 14 are charged by the charging means 12, Ct1 and Ct2 are also charged by the conductor 26. Therefore, in order to eliminate the charging path of Ct1, (10b) are all floated and no discharge path is formed. The CPU 40 and the signal processing unit 35 control the switching unit 16 to keep all the NSPs connected to the switching unit 16 floating. In the waveform diagram of FIG. 42, the state in which the NSP signal is high means that the NSP is in the open or floating state, and the row indicates that the NSP is connected to the ground through the switching unit 16.

It is preferable that the NSP 10a is opened before the touch capacitor Ct1 formed on the touch pad 10a for detecting a touch is charged. It is desirable that the open time is made 100ns before 1ns before charging starts.

42, the NSP 10a was opened by Vg before the charging means 12 was turned on. NSP open is possible even during charging. The TDI 30 has means for setting the time point at which the NSP is opened. This is performed by a value stored in a register or a memory or by a program that drives the CPU 40. [ For example, if register 00h is selected, NSP is opened in 1ns, and if 0Fh is selected, 100ms can be selected.

 In the region 1, after the charging by the charging means 12 is completed, the voltage due to the D / B development is formed and the stabilization is completed. Then, in the region 2, the voltage by D / B is detected. The voltage detected in the region 2 is sampled in a storage means such as a sample & holder or a capacitor (not shown) in the touch detection unit 14. [ Region 3 is an area where the sampled data is amplified or converted into a digital value by the ADC conversion unit 14-3 after the sampling process is completed. Therefore, in the area 3 where sampling is completed, the NSP that has been opened may be grounded to the ground. Grounding between the NSP and the ground should be within 1 ms to 100 ms from the end of the region 2 where sampling is completed.

On the other hand, if the touch pad 10 which is detecting the common voltage is open and closed (or connected to the ground by the switching unit) at the same time as the NSP, the path of the charge due to the touch pad 10, So that a malfunction of the touch will be prevented.

The TDI 30 has a means for determining the time when the opened touch pad 10 is closed. This is stored in a register or memory, or executed by a program that drives the CPU 40. [ For example, if register 00h is selected, NSP is opened in 1ns, and if 0Fh is selected, 100ms can be selected.

When the time for opening the NSP 10b is long, the time for the touch pad to function as the back ground is shortened. As a result, the possibility of causing image quality failure due to noise such as ESD becomes high as described above. Therefore, a method for reducing the open time of the NSP 10b is needed.

Referring to FIG. 41, Cdrv, Cvcom, and Cp are connected in parallel to the touch capacitor Ct. In a typical embodiment of the present invention, Cdrv or Cvcom is larger by a couple of times than Ct. Therefore, even if the touch capacitor Ct is removed after charge sharing at the point P is completed by D / B, the potential at the point P is not greatly affected. One of the reasons for this is that the P-point is floating at Hi-z, except when charging, so there is no discharge path. The fact that the remaining capacitors do not store Ct, and preserve the charge, is the fact that the capacitance due to Ct is reflected to generate the voltage by D / B using Equation 2, Since it is stored in a capacitor acting as a memory, it provides the theory that even if Ct is removed, there is no abnormality in touch signal detection.

Referring again to FIG. 41, since the movement path of the electric charge formed by the conductor 26 is blocked even if the SP 10a as the touch pad 10a used for touch detection is opened, Or a method of preventing a touch malfunction due to the conductor 26 such as a metal.

FIG. 43 shows an embodiment of the present invention relating to the open of the SP 10a. In Fig. 43, the flow and time of all signals except SP 10a are the same as those in Fig.

Referring to FIG. 43, after the voltage of D / B is formed by the driving voltage Vdrv and charge sharing is completed between all the capacitors connected to the point P, the SP 10a is opened in the region 1. (SP is high means SP is open, SP is low and SP is connected to ground.) When SP is open, NSP (10a) is reconnected to ground and after SP open Within 1 ns to 100 ms.

The time point at which the SP 10a is opened may be synchronized with Vg or with a common voltage Vdrv or not shown. It is preferable that the SP 10a is connected to the ground at the area 3 after the sampling is completed in the area 2 after it is opened.

And is connected to the ground within 1 ns to 100 ms after sampling is completed in region 2.

If the SP 10a continues to function as the SP 10a in the next sensing sequence, it must be connected to the P point before charging. Referring to FIG. 43, the open and close times of the NSP can be further shortened when interlocked with the SP 10a, which greatly helps the touch pad 10 to operate as a back ground.

The TDI 30 has means for controlling the time for opening or closing of the SP 10a and is implemented by a register, a memory, or a program. In addition, SP (10a) open serves to reduce the inflow time of noise introduced through the SP, thus also weakening the noise affecting the P point.

Referring to FIG. 37, since the touch pads 10 in the row 1 are located at a distance from the TDI 30 at a distance from the touch pad 10 in the row 7, the resistance formed by the sensor pattern 22 is larger and the parasitic capacitance Cp Big. Therefore, when opening the SP 10a shown in FIG. 43, the open time can be determined in consideration of the resistance or capacitance of the SP 10a. This is because the resistance or parasitic capacitance of the sensor signal line 22 connected to the Ct formed on the touch pad 10 increases with distance from the TDI 30 to the D / B at Ct due to Vdrv applied to Cdrv The voltage change or charge sharing caused by the RC is delayed by a factor according to the product of RC. Therefore, if the same SP 10a open time is applied to all the touch pads 10 of the touch screen panel 50, the touch pad 10 close to the TDI 30 performs signal sampling after completion of charge sharing, However, since the touch pad 10 at the remote location in the TDI 30 may perform signal sampling while the charge sharing between the capacitors connected to the P point is not completed yet, the touch sensitivity may be lowered or a touch coordinate detection error may occur It is possible.

In order to solve such a problem, it is necessary to change the open time of the SP 10a according to the position of the touch pad 10. For example, since Row1 in FIG. 37 is the farthest from the TDI 30 and the size of the resistor or parasitic capacitor is the largest, the means for adjusting the open time when the touch pad 10 of Row1, Respectively. In addition, there is a means for separately setting the time for opening the touch pad 10 of every Row such as R2 or R3 for each row. Such a method is performed by a register, a memory, or a program in the TDI, and detailed execution methods are as described above.

According to the embodiment of the present invention, the time for opening the touch pad can be variably operated according to the position of the touch pad, so that it is possible to perform accurate touch detection that is resistant to disturbance or noise.

On the other hand, R1 and R2 can be SP open at the same time and R1 and R2 and R3 can be SP open at the same SP open time at the same time. The number of touch pads 10 included in the group that performs the SP open at the same time can be selected by the designer and the number of the touch pads 10 to be included in the same group should be adjusted according to the resistance or size of the parasitic capacitors .

The TDI 30 has means for selecting the number of touch pads 10 to be included in the group that performs the SP open at the same time. If the register is used for this purpose, if address 0 of the register is selected and all the rows have an individual SP open time, if 01 is selected, two rows are included in the same group, And R2 or R3 and R4 are included in the same group. Or if you select address 03 in the register, it allocates 5 rows to the same group, and the rows of R1 to R5 will operate in the same SP open time.

It is advantageous that the resistance of the touch pad 10 to be included in the group for SP opening at the same time is as equal as possible. It is preferable that the resistance of the touch pad 10 included in the group that performs SP open at the same time exists within an error range within the range.

Although the above embodiments have been described with reference to a row as an example, the technical idea of varying the open time of the SP 10a according to the touch pad 10 is not limited to a row and is also applied to the case of selecting the touch pad 10 in a column or random manner .

On the other hand, in the embodiment related to the open time with respect to the NSP 10b or the SP 10a in Figs. 42 and 43, the touch signal is detected in synchronization with the common voltage, The open time of the NSP 10b or the SP 10a can be determined in synchronization with a signal generated in the TDI 30 or given outside the TDI 30 without being synchronized with the common voltage. A signal over the open or close given in the TDI 30 or outside the TDI 30 is a trigger signal generated by a timer or a counter by a counter or an interrupt.

The ON / OFF timing of Vg for controlling the charging means 12 is determined in synchronization with this signal, and the operating timing of all the signals shown in FIG. 42 and FIG. 43 is also determined in synchronism with these signals.

In FIG. 37, which is an embodiment of the touch screen panel 50 of the present invention, it is possible to scan a group of touch pads 10 included in a row or a group of touch pads 10 included in a row and detect a touch.

For example, when scanning is performed on the basis of Row, all the touch pads 10 included in the Row R1 are connected to the touch detection circuit where touch signals are detected at the same time, and sequentially from R1 to R7 And detects touch signals for all the touch pads 10 included in the same group at every scan.

In case of scanning in the column direction, scanning starts from C1 in the column direction, ends in C5, and starts again at C1 and ends at C5, and the touch is detected at every scan.

For example, in the case of scanning in the Row direction, when scanning R1, all the touch pads 10 included in the row R1 perform the touch detection operation. When all the touches included in the row of R2 through R7 The pads 10 will be connected to the ground potential.

In Row R1, a touch detection operation is performed a plurality of times (Multi times), and each time a touch is detected, the value is stored in a line memory corresponding to R1, and filtering is performed using a plurality of stored line memory data, It is judged whether or not it is touched or the contact area is calculated. After Row R1 is completed, the same process is repeated for R2. Touch data such as ADC value or area value extracted from each row after Row R7 is completed is stored in frame memory. The CPU 40 or the signal processing unit 35 calculates an area based on data stored in the frame memory or extracts touch coordinates.

The touch coordinates can be defined as the center of gravity of an area formed by the area of one or a plurality of touch pads 10 formed by the touch means such as the finger 25 opposed to the one or more touch pads 10. [ Accordingly, when the touch coordinates are calculated in consideration of only the ADC or area extracted from one touch pad 10, the center of the touch pad 10 is extracted as touch coordinates. In fact, since there are a lot of position information in the touch pad 10, it is impossible to extract a precise position with one touch pad 10.

In order to detect various positions existing in the touch pad 10, touch coordinates should be extracted by a combination of at least two or more touch pads 10. 44A and 44B illustrate embodiments of the present invention in which touch coordinates are extracted by a combination or relationship of the ADC or the calculated area detected by the touch pad 10.

Referring to Fig. 44A, the finger 25 has an area occupancy of 50% for each of the touch pad 10 "A" and the touch pad 10 "B". Assuming that A and B have the same area and have an area of 100, the sum of the touch areas by the finger 25 is 100, and the rate ratio of A and B is 50 each. Therefore, it can be determined that the center of gravity is at the center of A and B.

Referring to Fig. 44B, the area occupancy rate of the finger 25 at the touch pad 10 "A " is 60 and the area occupancy rate at the touch pad 10" B " The sum of the area occupied by A and B is 100, and the area occupied by A is 60, so the center of gravity exists at 40% from the left side of A, and this is touch coordinates. By the mutual relationship of the mutually adjacent touch pads 10, it becomes possible to linearly calculate the touch coordinates according to the small area difference.

In the example of FIG. 44, the touch coordinates of the finger 25 moving in the horizontal direction are obtained by using the touch pad 10 adjacent to the horizontal direction as an example. However, the touch pad 10 is positioned in the horizontal and vertical directions, When touch pads 10 in both the horizontal and vertical directions are touched, the touch coordinates can be extracted two-dimensionally.

Since the present invention is capable of extracting the area, the touch coordinates are extracted as an area, and the touch coordinates are preferably calculated by the correlation of the areas calculated by the respective touch pads 10. [

According to the coordinate detection structure using the above-described area, the touch detection means according to the embodiment of the present invention can perform touch detection with a resolution much higher than the touchpad resolution.

The TDI 30 used in the touch screen panel 50 of the present invention can be configured to detect touch signals of 100, 500 or more than 1,000 touch pads 10. In order to detect (or sense) a touch signal from one thousand touch pads 10, one thousand pins of the TDI 30 must be mapped on one-to-one basis with one thousand touch pads 10. Alternatively, if a multiplexer is installed outside the TDI and a multiplexer is connected to a touch pad 10 of one thousand, and the output of the multiplexer is made small, the number of pins of the TDI is reduced. However, since the multiplexer must be used separately, There is a problem that the cost is increased.

In order to manufacture the touch screen panel 50 to be used in a display device having a small screen size by using the TDI 30 capable of detecting the touch signals of the ten touch pads 10, Only some of the detection functions should be used.

For this purpose, in the embodiment of the touch screen panel 50 of the present invention composed of rows and columns as shown in FIG. 37, means for setting the operation region of the touch pad 10 included in the row and column is required.

For example, FIG. 37 shows a touch screen panel 50 having a row x column of 7 x 5. If the number of the touch pads 10 is limited to 5 x 3, 10), only five groups should be selected and only three of the five groups in the column direction should be selected.

In the TDI, there are means for selecting a touch pad group in a row direction and a touch group pad in a column direction that can perform a touch detection operation, and a register will be described as an embodiment of the means.

First of all, the register needs a register for selecting row direction group and two kinds of register for selecting column direction group. Two kinds of registers are also required in the register for selecting the row direction group, and each unit must have means for setting the start point and end point of the group to be subjected to touch detection. For example, suppose you have two registers, REG1 and REG2, that set the group in the row direction. REG1 is a register for setting the touch detection start point in the row direction, REG2 is a register for determining the end point, and the operation for touch detection is performed from the row R3 in FIG. 37 by R3 written in REG1 or selected. Do not. Also, only the touch detection operation is performed until R7 is written to REG2 or R7 selected in REG2, and thereafter, R8 or R9, which may be further thereafter, does not perform the touch detection operation. It is also possible to select three groups of column direction from C2 to C4 or from C1 to C3 by two registers which can be set in the same way for the column.

The operation of detecting the touch only on a part of the touch pads in the entire touch pad 10 that the TDI 30 can detect can be performed in two ways.

The first method is that only the touch pad 10 required for the touch detection operation is connected to the touch detection circuit as shown in Fig. 11, and the touch pad 10 excluded from the touch detection operation is not connected to the touch detection circuit of Fig.

Second, all the touch pads that can be detected by the TDI 30 are connected to the touch detection circuit to detect the touch, and data of a necessary area is extracted from the memory including the result value and used for touch coordinate calculation.

Alternatively, these two methods can be used in combination. Referring to FIG. 37, for example, only R3 and R7 operate in the row direction, R1 and R2 do not perform touch detection, C1 through C5 operate in the column direction, and only C1 through C3 data stored in the memory And data of C4 to C5 are ignored. Or C1 to C3 columns, C4 to C5 do not detect touches, but detect touches for all the rows of R1 to R7, but detect the touches of R3 to R7 Area.

As described above, the touch pad 10 is also used for detecting a touch, but it is also used for detecting a common voltage.

Referring to Fig. 45, the following will be described. 45 is an embodiment of the present invention for detecting the touch signal and the common voltage with the touch pad 10. [ Referring to FIG. 45, there are 15 touch pad groups in the row direction and 10 touch pad groups in the column direction, and 150 touch pads 10 constitute the touch screen panel 50. The reason why the common voltage is used in the display device 200 and which is an alternating common voltage such as a line inversion or a common voltage including noise is detected in synchronization with the common voltage has been described above.

In order to detect the common voltage, a means for forming Cvcom is required as in the embodiment shown in Fig. 17 or 19 for common voltage detection. In the present invention, the touch pad 10 is used without separately installing such means .

12 to 13, a touch capacitance Ct and a common electrode capacitance Cvcom are simultaneously formed on one touch pad 10.

That is, when the finger 10 is placed on the upper surface of one touch pad 10, the touch capacitor Ct connected to the point P of FIG. 11 is formed on one side of the body with the ground, And the other side is formed with a common electrode capacitor Cvcom having a potential of a common electrode located on the lower surface thereof. This means that the common electrode capacitor Cvcom is formed in the touch pad 10, meaning that the common voltage can be detected even if there is no separate common voltage detecting means.

Since the touch pad 10 can simultaneously detect the touch and the common voltage, it is also possible to detect the touch signal and the common voltage in the touch detection circuit as shown in Fig. 11 with one touch pad 10. [

However, in one circuit, crossing due to the difference in timing of detecting the touch signal and the common voltage may occur, and the driving voltage (Vdrv) for detecting the touch signal and the common voltage may affect each other, It is preferable to distinguish the touch-sensitive touch pad 10 and the common voltage-detecting touch pad 10 as much as possible.

17 and 19, since it is desirable not to use Cdrv in order to improve the detection sensitivity of the common voltage, it is preferable to separate the touch detection circuit including Cdrv and the common voltage detection circuit not including Cdrv .

Referring to FIG. 45, there are three row groups R9, R12, and R15 for the touch pad 10 for common voltage detection. In addition, five touch pads 10 detect a common voltage in one group.

Only one of the fifteen common voltage detecting touch pads 10 is selectively used for common voltage detection. Therefore, a multiplexer or switching means is required to connect one of the plurality of touch pads 10 set for common voltage detection to the P point (point P in Fig. 17) of the common voltage detection circuit. However, this is an embodiment according to FIG. 45, and a plurality of touch pads 10 and a plurality of corresponding common voltage detection circuits may be used.

45, when the touch detection area is set to 10 x 5 in row x column and the touch detection area is set to R1 to R10 and C1 to C5, only the common voltage detection touch pad 10 included in the touch detection area It is used for common voltage detection. In addition, the common voltage detecting touch pad other than the touch detection area is not used for detecting a common voltage. In this manner, the common voltage detecting pad 10 can be set in a plurality of rows and a plurality of columns, and the detecting position of the common voltage detecting pad can be changed according to the change of the touch area setting of the TDI 30. [

Assuming that the entire area of FIG. 45 is the touch detection area, the common voltage should not be detected only in the touch pad 10 included in one row, and at least one should exist in the other row.

This is because, in the embodiment where the touch signal is scanned from R1 to scan up to R15, when it is assumed that the touch pad with 5-tuple of R9 detects the common voltage at first, when touching R9 after scanning R8 The touch pad 10, which is detecting the common voltage to which the fifth voltage of R9 is written, must detect the common voltage and detect the touch, so that the other touch pad must detect the common voltage. This common voltage detection touch pad should not be present in R9 and therefore should be selected from one of R12 and R15. If it is assumed that the touch pad 10 in which R15 through R15 are written, the common voltage is detected in the touch pad in which R13 is written at the time of R9 scan, and common voltage is detected before R15 is scanned after R9 is scanned The voltage detecting pad may be switched to another common voltage detecting touch pad 10 of R9 or R12.

As described above, real-time common voltage detection using the touch pad is possible by changing the common voltage detection pad according to the scan order for touch detection.

In the case of the on-cell touch included in the display device as in the embodiment of FIG. 13, the touch pad 10 may be used as a back ground in the LCD device of the transverse electric field mode . In this case, if a single touch pad continuously detects a common voltage, the display quality of the display device may be affected. That is, when the touch pad 10 written in R9 of FIG. 45 continuously detects the common voltage and relays the common voltage detection function to the touch pad located in another row in the sequence in which it detects the touch, The time occupation rate for detecting the common voltage of the touch pad 10 to which the 5 is written is higher than that of the touch pad 10 for other common voltage detection. In order to detect the common voltage, since the charge voltage Vpre_com is applied to the common voltage detecting touch pad 10 for a considerable period of time as in the embodiment of FIG. 18, It is possible that the liquid crystal on the lower surface of the common voltage detecting touch pad 10 is operated by an electric field by generating an electric field with the voltage formed on the electrode or the drain electrode 255. When the liquid crystal reacts with such an electric field, it may cause image quality problems such as blacking of the whole part or changing to gray.

In order to solve such a problem, the common voltage detecting touch pad 10 is used by rotation.

For example, when detecting the first common voltage, assuming that the touch pad written with 1 in FIG. 45 R9 is used, the bipolar touch pad of R9 is used to detect the second common voltage, and then the common voltage detection The common voltage detecting touch pad 10 must be rotated as if the touch pad 10 in which R9 is written is used. Since the time width of the common voltage is long within 100us and the liquid crystal can not react in the time of about 100us, it is possible to solve the image quality abnormality by rotation of the common voltage detection pad. This rotation can be performed between the touch pads 10 for common voltage detection included in the same row or between the touch pads 10 for common voltage detection included in different rows or columns.

When the common electrode detection touch pad 10 rotates, when the row in which the common voltage is detected changes to the touch detection environment in order to detect the touch, the rotation of the common voltage detection touch pad is included in another row And the common voltage detecting touch pad 10.

Although the embodiments described above have been described with respect to the case of detecting the touch by sequentially scanning Row, the same rotation method can be used when the touch is detected by sequentially scanning the column.

Some phones have a function key to return to the menu of the menu or to perform a backward or forward operation of the menu. Referring to FIG. 46, which is a conventional embodiment relating to the use of a function key, a touch pad 10 and a function key 20 are provided on a touch screen panel 50 applied to a mobile phone. Although the function key 20 may be a mechanical type, in recent years, the use of a function key using a touch has been increasing.

46, there are two function keys and are provided in an area outside the A / A area of the display device on which the touch pad 10 is installed. Two function keys, which can be called "Home Key" and "Back Key", are used at positions different from the position of the touch pad 10 used for touch detection, and thus a function different from that of the touch pad 10 is required.

Figure 47 is an embodiment of the present invention relating to the implementation of a function key. Referring to FIG. 47, the TDI 30 is divided into an input unit and an output unit. The input unit may receive a signal from a flexible circuit board 96 such as a COF or an FPC or a COF or FPC. Also, the output portion of the TDI is a portion connected to the touch screen panel 50, and is an area where signals can not be transmitted elsewhere except for the touch screen panel 50.

The function keypad 20 is included in the output portion of the TDI 30 and can be wired together with the touch pad 10 to pass through the A / A top surface of the display device. The function key signal line 23a passing between the touch pads 10 is connected to the function key 20 in the area of the touch screen panel 50 opposite to the TDI 30. [ On the other hand, another function key signal line 23b originates from the output portion of the TDI 30 and does not pass through the A / A region of the display device, but passes through an invisible region (or bezel) Is connected to the function keypad 20 by being wired to the opposite touch screen panel 50 of the TDI 30.

Also, the function key 20 may be connected to a protective glass, a protective plastic or the like instead of the touch screen panel 50 through the input portion of the TDI 30. When the touch pad 10 of the present invention is used as a function key, only one pad is used independently and only on / off is detected. a threshold value for on / off detection may be used differently from a threshold value applied to the touch pad 10. [

The function keypad 20 also has fac. It is desirable to reduce the detection error by performing the same cal or RTC. When the function key does not exist on the upper surface of the display device, the function key need not detect the touch signal in synchronization with the common voltage.

The function key 20 can also be used as the touch pad 10. The TDI 30 includes a means for determining whether the arbitrary touch pad 10 is to be used for touch detection or as a function key. If rows x col are 7 x 5 as shown in FIG. 47, if five function keys are absorbed by the touch pad of the row, row x col becomes the touch screen panel 50 having a touch resolution of 8 x 5. This function is changed by a register or a program included in the TDI 30. For example, in the case of a register change method, a specific bit of a register is set to a low or a low level, whereby some of the touch pads are switched to a pad for touch detection or a function key pad. For this purpose, a specific area of the touch pad 10 should be determined in advance to perform these two functions.

The function key used in the present invention can also be used as a touch detection pad, so that it can be used as a function key for detecting a linear position change of a touching means such as the finger 25 in addition to a function key for simply detecting ON / OFF . These function keys are used for function keys that require a scroll function, for example, a part attached to one side of a mobile phone, a part where the volume is increased when a finger is pushed up and a scroll function where a volume is decreased when a finger is lowered.

In order to linearly detect coordinates of a linear position change of the finger 25, a function keypad can not perform such a function. As described above, a plurality of function keypads must be adjacent to each other, Linear coordinate detection can be performed through the relationship to area occupancy or cross area reference. This function is different from the case of detecting touch coordinates by the touch pad 10, except that the touch detection position is not the upper surface of the A / A of the display device.

Therefore, the touch pad of the present invention can be used for all purposes of extracting a linear coordinate change such as a scroll wheel of an Apple iPod.

When the touch pad 10 is used as the function keypad 20, the function keypad 20 preferably performs all functions for opening or closing the NSP 10b or the SP 10a.

As described above, since the function keypad 20 can be assumed to be one area of the touchpad 10, five function keypads can be defined as the eighth row as shown in FIG. Therefore, the touch screen panel 50 having the resolution of 8 x 5 can be set, so there is no restriction on the function or time setting for the open or close of the NSP or SP. 47, when all the touch pads 10 of the touch screen panel 50 including the function keys 20 are connected to the ground or when the first row of the touch pad 10 is operated as the NSP open of the present invention Can be followed.

Also, at the moment when the touch key is detected by the function key 20, the remaining touch pads 10 except for the function key 20 can apply the technical idea of the NSP open of the present invention. As a result, the timing of the NSP open or SP open of the function key (20 or function keypad) is not set separately but is performed in synchronism with the time of the NSP or SP open of the touch pads 10.

When the touch pad 10 of the present invention is used as the function key 20, a threshold value for determining whether or not the touch is to be performed must be set separately, and the threshold values for the ADC or the area may be set to be the same or different from each other .

This is because, for that purpose, the function key 20 needs to separately set the sensitivity, such as reacting after a lot of pressing.

If the sensitivity of the function key is sensitive like a general touch, it also reacts to the instantaneous touch, and such sensitive sensitivity is not necessary in some cases. Therefore, it is preferable that the threshold value for determining whether or not the touch key is set to the function key 20 is separately set.

 The threshold value may be set based on the ADC value or based on the area. It is also preferable to separately set the gain of Fig. 29 for the touch detection of the function keypad. This is because the touch sensitivity can be adjusted.

FIG. 48 shows an embodiment of a register setting of the present invention applied to a function key. Referring to FIG. 48, since the register has 4 bits, it can be set to 16 steps. The threshold value is set based on the ADC code. If the address 00h of the register is selected, the threshold value becomes 50. If the ADC detected by the function keypad 20 is 50 or more, it is recognized as a touch. Also, if 09h is selected, it is recognized as touch only when the ADC code value detected by the touch on the function keypad 20 is 500 or more. In this way, it is possible to adjust the touch sensitivity of the function keypad 20 by appropriately adjusting the threshold value, and this method is also applied to the touch detection of the touch pad 10 as well.

Assume, on the other hand, that the finger 25 should completely cover the function key so that the touch is detected while the sensitivity is low. In such a case, as shown in the equation of FIG. 29, it may be solved by lowering the gain or adjusting the threshold value for the touch detection. Alternatively, the sensitivity can be adjusted to the shape of the function key.

According to the above-described configuration, an embodiment of the present invention can provide a user with a different input method from the touch pad by adjusting the touch detection threshold value of the function key and the gain of the amplifier while having the same structure as the touch pad.

Figure 49 is an embodiment of the present invention for adjusting sensitivity in the shape of a function keypad. Referring to FIG. 49, the touch detection pattern in the function keypad 20 has a net structure, and the area occupancy of the touch detection pattern is determined according to the width of the pattern. In FIG. 49, the net structure is described as an example, but the present invention is not limited to the shape, and the sensing pattern may occupy a part of the functional key pattern and cover the entire functional keypad. The advantage of such a pattern is that even if the gain or the threshold value is set high, the touch detection can be performed only when the touch means is contacted to the functional keypad 20 so that the touch detection is performed by touching a part of the function keypad 20 unconsciously It is possible to prevent an operation due to an unwanted touch.

According to the above-described configuration, an embodiment of the present invention can provide the user with an input function as a function key that is different from the touch pad easily by partially changing the structure of the touch pad 10. [

In order to extract the touch coordinates from the touch pad 10, it is necessary to define the mutual relationship with the surrounding touch pads 10. This relationship is the area of the finger 25 composed of the plurality of touch pads 10 contacted with the finger 25 when the finger 25 touches the plurality of touch pads 10, When the center of gravity of the area constituted by the reference point 10 is obtained, the point is the touch coordinates. However, since the peripheral touch pad 10 is not provided at the edge of the touch screen panel 50, which is the last portion of the touch pad 10, it is difficult to obtain a perfect center of gravity.

50 is a conventional embodiment relating to the configuration of the edge portion of the touch screen panel 50. Fig. Referring to FIG. 50, the touch pad 10 is disposed in the A / A of the display device. As described above, since the conventional touch detection method has a wide width of the right and left bezels due to the touch screen panel 50, the configuration of the touch pad 10 exceeding the A / The width of the left and right bezels is further widened, resulting in lower merchantability. Because of this, there is no touch pad 10 connected to the edge of the touch pad 10, so that a blind spot of detection occurs.

Fig. 51 is an embodiment of the present invention for solving such a problem.

Since the sensor signal line 22 of the present invention is disposed within the A / A of the screen of the display device between the touch pads 10, the sensor signal line 22 installed on the left and right bezels of the touch screen panel 50 ) Is minimized.

Therefore, even if the touch pad 50 is installed beyond the A / A of the screen, the bezel width of the touch screen panel 50 is not increased. As shown in FIG. 51, when the touch pad 50 is extended to the outer edge of the display device A / A, the detection blind spot is pushed out of the display device A / A.

The present invention recognizes the touch coordinate recognition and the contact area between the touch pad 10 and the touch means such as the finger 25. Referring to FIG. 14, the present invention can calculate the area of the finger 25 opposed to the touch pad 10, so that when a contact area for a plurality of the touch pads 10 is increased, 50 is calculated. It is also possible to obtain touch coordinates by obtaining the center of gravity of the area. Accordingly, if the touch coordinates are displayed on the two-dimensional x and y axes and the area information is displayed as touch coordinates, it becomes possible to display the touch in three dimensions.

It is also possible to detect a force or a pressure by the finger 25 by calculating the rate of area change per unit time of the finger 25 that is in contact with the touch screen panel 50. In order to perform such an operation, the present invention transmits time information and area information when the touch coordinates are transmitted to the set CPU, and the CPU of the set calculates force or pressure of the touch means based on this information. Or the CPU 40 in the TDI or the signal processing unit 35 calculates the force or pressure applied by the touching unit and transmits it to the cpu of the set.

This area detection can be used for various purposes. For example, in the case of writing, the writing may become thicker or narrower in proportion to the area of the writing tool in contact with the touch screen panel 50, and when the conductive brush is used to draw the picture, it is possible to draw the same picture as the actual writing . In addition, some applications can implement multi-layer command using area. To operate an MP3 player on a mobile phone, 1) a step of selecting an MP3 player among several applications, and 2) a two layer command, which is a step of touching a play button to hear a song, is common. In this case, since the area of the multi-layer structure command using the area of the present invention is small when the user presses the MP3 player, the player is selected and the contact area is widened by pressing a lot. Alternatively, in the case of a piano application, the magnitude of the sound may vary depending on the strength of the piano keyboard.

Meanwhile, a plurality of the TDI 30 of the present invention can be used in one touch screen panel 50. If the touch pad 10 is disposed on the touch screen panel 50 with one TDI 30 when the touch screen panel 50 is wide, the area of the touch pad 10 is widened, It is preferable to reduce the area of the touch pad 10 by using the plurality of TDIs 30. [

The touch pad 10 formed on the touch screen panel 50 for using a plurality of TDIs 30 on one touch screen panel 50 includes a touch pad 10 in the row direction and a touch pad 10 in the column direction. Must be composed of the same lines or equally spaced.

52 shows an embodiment of the present invention in which a plurality of TDIs 30 are used. Referring to FIG. 52, a plurality of TDIs 30 are used in one touch screen panel 50, and the touch pads 10 are patterned at equal intervals. Communication and signal lines 29 are provided between the plurality of TDIs 30, and communication and necessary signals are transmitted between the plurality of ICs. A plurality of signal lines are used for the communication and signal lines 29. These are I2C, SPI signal lines, or USB signal lines for serial communication, and are a plurality of synchronization signal lines to be described later. One of the plurality of TDIs 30 is given a master function and the remaining is assigned a slave function. TDI includes means for specifying master and slave functions.

The TDI 30 used as a master sends a control signal to the TDI used as a slave through a communication line and a signal line 29 to control the function of the slave. Although not shown, a CPU 40 other than the TDI 30 exists separately from the TDI 30 and controls the plurality of TDIs 30 via the communication line and the signal line 29. [ In this case, each TDI 30 needs a function of assigning an ID to the TDI 30, and the TDI 30 has a hardware pin or a software configuration for setting an ID. For example, in a hardware configuration, multiple ID pins connect a low or low signal.

The touch pad 10 controlled by the two TDIs 30 of the touch screen panel 50 is controlled by one TDI 30 so as to prevent malfunction due to the contact of the conductive material such as water drops . For example, assuming that Row is scanned, the scan starts from R1 and ends at R7 via R2 and R3, the master TDI 30 or an external CPU sends a frame synchronization signal through a signal line or a communication line 24 . frame synchronous signal, the R1 on the left side of FIG. 52 and the R1 on the right side start the scan at the same point in time. After the scan of R1 is completed, the master TDI or the external CPU signals to start the scan of R2, and the scan of R2 is performed in synchronization with this signal. The scan start point of the frame and the scan start point of each row are synchronized by the signal applied by the master TDI or the external CPU, so that it operates as if it is operated by one TDI, and malfunction due to the conductor such as water drops is prevented. Also, since the operation of the NSP or the SP is synchronized with the operation of the plurality of TDIs 30, the same operation as that of one TDI 30 is possible.

As described above, it is possible to provide a large-sized touch screen function by operating a plurality of TDIs as a master-slave and synchronizing a scan and a pad opening.

Meanwhile, when the touch screen panel 50 according to the present invention is actually used, static electricity (ESD) flows in from time to time. When static electricity is applied to the touch pad 10, the potential at point P in FIG. As shown in FIG.

Referring to FIGS. 12 to 13, the touch pad 10 of the present invention is located on the lower surface of the glass-like protector 24. Thus, the static electricity will be applied to the protective layer 24 and then to the junction of the protective layer 24 and the touch pad 10. 12 to 13, static electricity is drawn from the edge of the touch screen panel 50, so that if the edge of the touch screen panel 50 is provided with means for absorbing static electricity, It will not penetrate into the interior of the housing 50.

53 is an embodiment of the present invention for removing electrostatic discharge (ESD). Referring to FIG. 53, an ESD absorption line 27 is installed at an outer portion of the touch screen panel 50. The ESD absorption line 27 is connected to a ground or a DC having a constant potential in a flexible circuit board 96 such as a COF or an FPC or connected to the TDI 30 and connected to a ground potential inside TDI or a DC potential having a predetermined level do. It is also undesirable that the ESD absorption line 27 forms a closed loop. This is because the antenna effect can affect the call reception sensitivity of a mobile phone or the like. This causes the ESD absorption lines 27 to originate from at least two points and are not interconnected. It is also preferable to overlap with the shortest distance in order to minimize the ESD path as in the circular part of FIG.

Since the ESD absorption line 27 is connected to the GND or the predetermined DC level, the ESD drawn at the edge of the touch screen panel 50 is absorbed by the ESD absorption line 27 and discharged to the outside of the touch screen panel. The pad 10 is safely protected.

54 and 55 are a cross-sectional view and an exploded perspective view of a display device incorporating a touch screen panel. A touch screen panel according to the present invention and a display device including such a touch screen panel will now be described with reference to the drawings.

As shown in FIG. 54, the touch screen panel according to the present invention can be patterned on the upper surface of the color filter 215 of the display device 200. (Which may be located on the lower surface of the TFT substrate, but a description thereof is omitted in this specification). A common electrode 220 is formed on the lower surface of the LCD color filter 215. As another example, the common electrode 220 is formed on the TFT substrate 205 in the transverse electric field mode as shown in FIG. In the example as shown in FIG. 34 or 54, the touchpad 10 is patterned and installed on the upper surface of the color filter 215 as shown in FIG.

The patterning process may be performed at the manufacturing stage of the color filter 215 or may be performed after the TFT substrate 205 and the color filter substrate 215 are combined. In recent years, in order to reduce the thickness of a display device, a slimming process is often performed after the two substrates are combined to reduce the thickness. Therefore, the patterning process of the touch substrate 10 is performed after the slimming process is completed The touch substrate 10 is not lost.

On the other hand, a protective panel 52 such as tempered glass may be provided on the touch pad 10 to protect the touch pad 10. 54, the protection panel 52 may be attached to the upper surface of the color filter 215 by a transparent adhesive such as an ultraviolet curing resin 98 or the like, and may be attached to the edge of the protection panel by DAT (Double Adhesive Tape) It is also attached.

The touch screen panel of the present invention formed on a display device such as an LCD detects a common voltage and detects a touch signal in synchronization with the common voltage when the display device alternates with a common voltage such as a line-inversion driving method of an LCD. In the case of a transverse electric field mode or a dot-in version, a driving noise is generated in the driving process of the liquid crystal. When the driving noise affects the touch signal, the driving noise is detected. Is detected.

54 and 55, a polarizer is attached to the upper surface of the touch pad 10 of the present invention.

In the illustrated example, a drive IC 60 for displaying a screen of an LCD is mounted on the TFT substrate 205 in a COG form. The TDI 30 for controlling the touch signal is mounted on the color filter 215 in a COG or COF form. In the respective drive ICs 30 and 60, the flexible circuit boards 96 and 97 such as FPC and COF are drawn out. On the other hand, in the embodiment as shown in FIG. 55, the TDI 30 and the LCD drive IC 60 may be integrated into a single IC.

On the other hand, the present invention can detect a plurality of taps. Referring to FIG. 25, the touch pad 10 of the present invention has independent coordinates at independent positions. Accordingly, each touch pad 10 can detect a plurality of touches with respect to a plurality of touch inputs. If it is assumed that a palm (not shown) on the upper surface of the 35 touch pads 10 shown in FIG. 25 covers all the 35 touch pads 10, it is possible to detect that all the 35 touch pads 10 are touched .

If the area of the touch pad 10 of the present invention is small, the touch means such as the finger 25 opposed to the touch pad 10 will generally be opposed to the plurality of touch pads 10. Accordingly, since a plurality of touch pads 10 are brought into contact with a single touch unit, it is necessary to detect a single touch coordinate in a group composed of a plurality of touch pads 10. These touch coordinates become the center of gravity of the group to which the touch is made.

56 is an embodiment of the present invention relating to touch group determination. 56, " finger A "touches 10 touch pads 10, and relative values of the areas extracted due to the touch of the finger are displayed on each touch pad 10. [ In the second row of the ten touch pads 10, the area after the area 9 and the area 7 is 0. Therefore, it can be seen that only the touch occurs up to 7, and the touch does not occur thereafter. 0 is the boundary of the touch.

If the touch occurs, the area is extracted. If the touch is not generated, the area is not detected. Therefore, the boundary between the two areas can be identified. By combining the boundaries, Do. The plurality of touch pads 10 are recognized as one touch pad by grouping the areas of the touch pads 10 included in the touch area into a group in which the touch is generated by one finger When the center of gravity of one group is obtained, this is the touch coordinates of the group.

56 is a separate group that does not correlate with the group of "finger A" in FIG. 56, it is also possible to extract the touch coordinates which is the center of gravity of the group of " finger B " Since it is possible to simultaneously extract the touch coordinates of the "Finger A" group and the "Finger B" group, the present invention is capable of multi touch detection that simultaneously detects a plurality of touches.

As described above, the display device incorporating the touch screen panel of the present invention has a simpler process than the conventional method in which the touch pad 10 is formed on a film or glass and the film or glass is attached to the display device, Since the film is not used, the thickness is thinned and the transmittance is increased. In addition, when the touch screen panel of the present invention is manufactured on the top surface of an LCD using an LCD process suitable for mass production, it is possible to produce products with low cost and high yield.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention as defined by the appended claims. Will be clear to those who have knowledge of.

10: touch pad 10a: sensing pad (SP)
10b: Non-sensing pad (Non SP) 11: Space-
12: Charging means 12-1: Output of charging means
12-2: input unit of charging means 14: touch detection unit
15: common voltage detecting unit 16: switching unit
18: Amplifier 18a: Differential amplifier
19: Comparator 20: Function Key (Function Key)
22: sensor signal line 23: function key signal line
25: finger 26: conductor
27: ESD absorption line 29: communication and signal line
30: Touch Drive IC (TDI) 31: Driver
33: timing control section 35: signal processing section
40: CPU 46:
47: power supply unit 50: touch screen panel
52: protective panel 57: adhesive member
58: air gap or contact member 59:
60: drive IC 90: active area
92: Invisible area 96: Flexible circuit board
98: ultraviolet ray hardening resin 200: display device
205: TFT substrate 210: liquid crystal layer
215: Color filter 217: Background
220: common electrode 230: sealant
242: gate line 244: data line
246: common electrode line 248: pixel electrode line
250: TFT 251: gate electrode
253: source electrode 255: drain electrode
257: semiconductor layer 270: dot

Claims (31)

A touch detection means installed in a display device and detecting that a touch capacitance Ct is generated by approaching a touch input means such as a finger of a user or a similar conductor,
A touch pad forming a touch capacitance (Ct) with the touch input means;
A driving capacitor Cdrv having one side connected to the touch pad and a driving voltage for touch detection applied to the other side;
A touch detection unit connected to the touch pad and detecting a touch signal using a driving back phenomenon when the touch capacitance Ct is added to the driving capacitor Cdrv according to whether the touch input unit is touched or not, ; And
And a memory unit for storing the touch signal detected by the touch detecting unit, wherein the memory unit includes a plurality of lines for grouping touch signals of the touch pad in one of a horizontal direction and a vertical direction of the touch pad, And a memory.
The method according to claim 1,
The touch detection means
A common voltage detector for detecting a common voltage generated in the display device; And
Further comprising: a driving voltage generation unit for generating a driving voltage in synchronization with the common voltage.
The method according to claim 1,
Wherein the memory unit comprises a frame memory for storing a sensor signal of the touch pads and a detected voltage value in one frame when the set of touch pads is referred to as a frame.
The method according to claim 1,
Volatile memory such as a flash memory or an E2PROM and a volatile memory such as an SRAM or a DRAM, and the nonvolatile memory may store a result of factory correction, a register value, or a program necessary for operating the CPU, Wherein said touch detection means comprises:
The method according to claim 1,
And a common electrode capacitance (Cvcom) is formed between the touch pad and the common electrode of the display device.
3. The method of claim 2,
Wherein the common voltage detecting unit is connected to the driving capacitor (Cdrv).
3. The method of claim 2,
Wherein the touch pad is connected to a touch detection unit or a common voltage detection unit.
3. The method of claim 2,
And a charging means for applying a pre-charge voltage to the touch pad connected to the common voltage detecting portion.
9. The method of claim 8,
Wherein the charging means is a switching element and the output portion of the switching element connected to the touch pad connected to the common voltage detecting portion when the common voltage is detected is in a high impedance state.
9. The method of claim 8,
Wherein the charging means is maintained in an off state for a predetermined time, and the common voltage detecting section detects the common voltage when the charging means is in an off state.
9. The method of claim 8,
And the charging means performs on / off in synchronization with the common voltage.
9. The method of claim 8,
Further comprising means for setting a charging time of the charging means.
13. The method of claim 12,
Wherein the driving voltage is applied to one side of the driving capacitor (Cdrv) in synchronization with any one of the common voltage and the charging time.
3. The method of claim 2,
Wherein the touch detection unit detects a touch signal after a predetermined time after the driving voltage is applied.
3. The method of claim 2,
And the input of the common voltage detection unit is in a high impedance state.
3. The method of claim 2,
Wherein the signal output from the common voltage detector is input to a comparator to detect whether the common voltage is high or low.
17. The method of claim 16,
Wherein either the upper reference voltage for detecting the Hi state of the common voltage or the lower reference voltage for detecting the Low state of the common voltage is input to the comparator.
3. The method of claim 2,
Wherein at least one or more touch pads are sequentially used in the touch pad contacted to the common voltage detecting unit.
3. The method of claim 2,
Wherein when the touch pad connected to the common voltage detecting unit is connected to the touch detecting unit, another touch pad not connected to the touch detecting unit is connected to the common voltage detecting unit to detect the common voltage.
3. The method of claim 2,
And means for outputting a signal of the common voltage detection unit to the outside of the TDI (Touch Drive IC).
21. The method of claim 20,
Further comprising means for determining whether to output the signal of the common voltage detection unit to the outside of the TDI.
The method according to claim 1,
The voltage detected by the touch detection unit 14 in the absence of the touch failure is determined by the following Equation 1 and the voltage detected by the touch detection unit when the touch capacitance Ct is added is calculated by the following Equation 2 , And the driving back is generated by a difference between Equation (1) and Equation (2).
&Lt; Formula 1 >

&Quot; (2) &quot;

(here,

Vh is a low level voltage applied to the driving capacitor, Cdrv is a driving capacitance, Cvcom is a common electrode capacitance, Cp is a parasitic capacitance And Ct is the touch capacitance.
23. The method of claim 22,
Wherein the touch detection unit detects the touch area of the touch input unit with respect to the touch pad in accordance with the size of the driving bag.
The method according to claim 1,
And the sensor signal line is located on the right and left sides of the touch pad.
The method according to claim 1,
Wherein the non-detecting touch pad connected to the touch detecting unit and excluding a touch pad detecting a touch is in a floating state.
26. The method of claim 25,
Wherein the non-detecting touch pad has a floating state before the charging means of the touch detecting unit is turned on.
The method according to claim 1,
Wherein a touch pad connected to the touch detection unit is separated from the touch detection unit after a driving voltage is applied to the driving capacitor Cdrv connected to the touch detection unit.
28. The method of claim 27,
Wherein the time at which the touch pad connected to the touch detection unit is disconnected is within 1 ns to 100 us after the driving voltage is applied to the driving capacitor connected to the touch detection unit.
28. The method of claim 27,
Wherein the touch detecting unit separates the touch pad from the touch detecting unit and then reconnects to the touch detecting unit or applies a predetermined voltage after the touch sensing unit completes touch sensing.
30. The method of claim 29,
Wherein the predetermined voltage is a ground (GND) or a DC voltage of a predetermined magnitude.
The method according to claim 1,
And a DC voltage of ground or a predetermined magnitude is applied to the floating touch-sensitive touch pad after the touch sensing operation of the touch detection unit is completed.

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