TWI469011B - Touch control system and sensing method thereof - Google Patents

Description

Touch system and sensing method thereof

The present invention relates to a touch system and a sensing method thereof, and more particularly to a touch system that monitors a current change using a turn-off signal as a trigger signal detection method and a sensing method thereof.

With the continuous advancement of technology, various information devices are constantly being introduced. Among them, in the case of data input devices, as data processing capacity is increasing day by day, if data is input only by keyboard or mouse, and data is output by screen, It seems too slow, so the touch panel is born. The touch panel has user-friendly input interface features and can operate more intuitively, so that users of any age can directly select the function options on the touch panel with a finger or a stylus. Bring great convenience.

For the current technology of the touch panel, as shown in FIG. 1 , it is a circuit diagram of the prior art thin film transistor matrix touch system. The touch control system includes a touch substrate 10 and a touch control circuit 12 . The touch substrate 10 is provided with an array of a plurality of sensing electrode units 14 , and two sets of intersecting control electrode line groups 16 and detection electrode line groups 18 . Each of the sensing electrode units 14 includes a TFT element 142 and a sensing electrode 144 that connects the TFT element 142. The control electrode line group 16 and the detection electrode line group 18 are respectively connected to the gate and the source of the TFT element 142, and the sensing electrode unit 14 is connected to the drain of the TFT element 142. The control electrode line group 16 is for controlling the opening and closing of the TFT element 142, and the detection electrode line group 18 is connected to the sensing electrode 144 through the TFT element 142.

The touch circuit 12 includes a control circuit 122, a signal detecting circuit 124 and a driving source 126. The signal detecting circuit 124 is electrically connected to the driving source 126 and the detecting electrode line group 18; the control circuit 122 is electrically connected to the control electrode line group 16. Control circuit 122 is controlled in a row-by-row manner by scanning Each of the control electrode lines of the electrode line group 16 outputs an ON signal such that the TFT element 142 connected to the control electrode line having the ON signal is in an ON state, and the remaining TFT elements 142 are in an OFF state. Therefore, the control circuit 122 controls the TFT element 142 on the electrode line group 16 to be in a conducting state, and the detecting electrode line group 18 inputs the touch signal of the driving source 126 to the detecting electrode line with the opening signal to make the touch thereon. The control signal flows into the sensing electrode 144 connected to the row control electrode line through the TFT element 142. Thus, as the control circuit 122 outputs an ON signal to each control electrode line row by row, the signal detection circuit 124 detects the magnitude of the change of the touch signal on the sensing electrode unit 14 connected to the row of control electrode lines line by line. When touched, the detection electrode line whose variation exceeds a certain threshold value can be found; and according to the control electrode line of the TFT element 142 turned on at this time, the sensing electrode unit 14 that generates the leakage current can be confirmed, thereby finding out Touch the location.

The above-mentioned conventional architecture can only detect the touch position and cannot display it. Therefore, it is necessary to externally mount another display substrate. For example, the two separate touch substrates and the display substrate are combined into a touch display by using a bonding process. However, this design increases the complexity of the circuit and the flaws in which the volume cannot be thinned. Furthermore, when the change of the touch signal on the detecting electrode line is small, the touched position cannot be accurately detected; therefore, how to improve The sensitivity of detection and effective reduction of volume and cost reduction are urgent problems to be solved.

In view of the above, the present invention provides a touch system and a sensing method thereof to effectively overcome the above problems in view of the above-mentioned shortcomings of the prior art.

The main purpose of the present invention is to provide a touch control system and a sensing method thereof, which combine the display circuit and the touch circuit, and use the common electrode for display to use the AC signal as a trigger signal to change the thickness of the overall touch display module. Thin, in response to the trend of modern technology to pursue light and thin.

Another object of the present invention is to provide a touch system and a sensing method thereof that can adjust a voltage to amplify a detection signal to improve detection sensitivity.

To achieve the above objective, the present invention provides a touch control system including a plurality of control electrode lines, a plurality of detection electrode lines, and a plurality of sensing units. The detecting electrode lines are alternately arranged with the control electrode lines, and the plurality of sensing units are respectively connected to the control electrode lines and the detecting electrode lines. Each sensing unit includes one of the first switching element and the second switching element connected in parallel and one sensing electrode connected to the second switching element, and the sensing electrode is coupled to a common electrode, which is a common electrode of the display circuit, and is colored The trigger signal of the touch transistor array on the filter substrate; when the trigger signal is an AC signal, a trigger signal may be provided to the sensing electrode by the common electrode. The control electrode line selectively outputs the off signal to each of the first switching elements in sequence, and the detecting electrode line cooperates with the detecting and sensing unit corresponding to the off signal; when the touch is generated, the sensing electrode turns on the second switching element accordingly The degree of opening enables the detection electrode line to detect a change in the current signal on the sensing unit, thereby obtaining at least one touch message.

The present invention further provides a touch sensing method, comprising the steps of: providing a trigger signal to a plurality of sensing units; sequentially switching the closing of each sensing unit, and sequentially detecting the current signal of the sensing unit; and detecting The current signal changes, the output corresponds to one of the touch messages, and the current signal of the sensing unit is continuously detected repeatedly.

The purpose, technical content, features and effects achieved by the present invention will be more readily understood by the detailed description of the embodiments.

The invention provides a novel touch system, which combines a display substrate and a touch substrate into the same circuit, and relatively simplifies the process, thereby effectively reducing the overall volume of the product and reducing the cost. Details are detailed later. As shown in Fig. 2, it is a circuit diagram of the present invention. The touch control system includes a plurality of control electrode lines 20, a plurality of detection electrode lines 22, and a plurality of sensing units 26; wherein the plurality of sensing units 26 are arranged in an array on a color filter substrate 24, and the detections are performed. The electrode lines 22 are interleaved with the control electrode lines 20, and each control electrode line 20 is isolated from the intersection of each of the detection electrode lines 22 by an insulating layer. The sensing unit 26 can be disposed on the upper surface or the lower surface of the color filter substrate 24 in an array to omit the manufacturing cost and complexity of the sensing unit. . The sensing units 26 are respectively connected to each of the control electrode lines 20 and each of the detecting electrode lines 22; each sensing unit 26 includes one of the first switching element 262 and a second switching element 264 in parallel and the second switching element. One of the sensing electrodes 266 is 264.

Each of the control electrode lines 20 is connected to the same row of first switching elements 262; each of the detecting electrode lines 22 is connected to the sensing units 26 connected in series. In detail, the gates of the first switching element 262 and the second switching element 264 are respectively connected to the control electrode line 20 and the sensing electrode 266; the drains of the first switching element 262 and the second switching element 264 are connected; The sources of the first switching element 262 and the second switching element 264 are connected. Each of the detecting electrode lines 22 is connected to the drain of the first sensing unit 26 and the source of the last sensing unit 26 (that is, the last row of sensing units arranged in the array), and the sensing unit 26 The drain is connected in series with the source of another adjacent sensing unit, and is serially arranged as a detecting electrode line.

The touch system further includes a touch circuit 28 and a display circuit 30. The display circuit 30 is electrically connected to the touch circuit 28. The touch circuit 28 includes a control circuit 282 and a signal detection circuit 284 respectively connected to the control electrode lines 20 and the detection electrode lines 22. The sensing electrode 266 of each sensing unit is coupled to a common electrode 32, and the common electrode 32 is connected to the display circuit 30, The common electrode 32 is a common electrode for display, and a trigger signal of the alternating voltage can be supplied from the common electrode 32 to the sensing electrode 266. The control circuit 282 drives the control electrode lines 20 to output a turn-off signal to the first switching element 262 in a scanning manner. At this time, the signal detecting circuit 284 cooperates with the off signal to detect the detecting electrodes 22 on the detecting electrode line 22. The current signal changes. It should be noted that when the control electrode lines 20 do not provide a turn-off signal, the first switching elements 262 are in a continuously on state, and the first switching elements 262 are in a closed circuit. Therefore, the sensing electrodes 266 continuously provide an alternating current. The trigger signal of the voltage is applied to the second switching element 264 such that the degree of opening of the second switching element 264 varies with the AC voltage provided by the common electrode 32, and the degree of opening of the second switching element 264 is less than that of the first switching element 262. Since the display liquid crystal can only accept a voltage of 0 to 4 volts, the startup voltage of the design common electrode 32 is about ±2~3 volts, in other words, when the common electrode 32 provides a trigger signal to the sensing electrode 266, That is, the coupling is formed. At this time, in the case of no touch, the sensing electrode 266 can provide a stable AC trigger signal to the second switching element 264; of course, the degree of opening of the second switching element 264 is necessarily smaller than the first switch. Element 262, because the first switching element 262 is a thin film transistor, is characterized by requiring a startup voltage of 15 volts to fully open the gate to form an on state.

Please refer to FIG. 2, FIG. 3 and FIG. 4 at the same time. FIG. 3 is a circuit diagram of the sensing unit of the present invention; FIG. 4 is a waveform diagram of the circuit signal of the present invention. The control circuit 282 drives the control electrode lines 20 to output a turn-off signal to the first switching element 262 in a scanning manner, such as the waveform of the Vsel signal outputted by the control electrode line 20, and N to N+5 is expressed as a progressive line. The Vsel signal is output to sequentially control the sensing units 26 arranged in the array, for example, the first behavior N, the second behavior N+1, and so on. The common electrode 32 continuously provides an AC trigger signal (such as a waveform diagram of the common electrode signal) to the sensing electrode 266 to form a coupling effect between the two, such as a coupling capacitor (C _com ), which is sensed without being touched. The degree of opening of the second switching element 264 controlled by the electrode 266 is a regular change. When the at least one sensing unit 26 is touched, the sensing electrode 266 correspondingly generates a sensing capacitor 34. At this time, the current on the sensing electrode 266 is discharged, and the voltage on the gate of the second switching element 264 is changed. The detection electrode line 22 detects the change of the current signal on the sensing unit 26, thereby obtaining at least one touch message, such as a waveform diagram of the detection electrode signal. In other words, during the touch of the sensing unit 26, the sensing electrode 266 does generate a leakage current phenomenon, thereby causing the current regularity of the detecting electrode line 22 to be affected. Each of the sensing units 26 further includes a passive component 36, such as a capacitor, having two ends connected to the gate of the first switching component 262 and the control electrode line 20, respectively. Since the common electrode 32 only supplies an AC voltage of ±2 to 3 volts, the degree of opening of the second switching element 264 by the sensing electrode 266 is only a slight change, and there is a possibility that the detected condition may not occur. Therefore, in order to improve the sensitivity of the detection, in the circuit design, the two ends of the detection electrode lines 22 are respectively connected to a power supply terminal (Vdd) and a ground terminal (Vss) of the signal detection circuit 284. That is, the first row sensing unit 26 arranged in the array is connected as an initial end to the power supply end; and the last row of the sensing unit 26 arranged in the array is connected to the ground end to form a voltage difference, and the voltage of the power supply terminal can be adjusted. When the detection signal is amplified so that at least one sensing unit 26 is touched, a slight current change on the sensing unit 26 can also be detected, thereby increasing the sensitivity of the detection.

Please refer to FIG. 2 and FIG. 5 at the same time. FIG. 5 is a flow chart of the steps of the present invention. In step S10, a trigger signal of an alternating voltage is provided to the plurality of sensing units 26. The sensing units 26 are arranged in an array, and are connected through a plurality of control electrode lines 20 and a plurality of detecting electrode lines 22 which are alternately perpendicular to each other. Then, in step S12, the control electrode lines 20 are sequentially switched. A sensing unit 26 is turned off, and then the detecting electrode lines 22 are sequentially connected to detect the power of the sensing unit 26 Streaming signal. On the other hand, when the sensing unit 26 is not switched, the first switching element 262 of each sensing unit 26 is continuously turned on. At this time, the sensing electrode 266 of each sensing unit 26 provides a trigger signal to The second switching element 264 is connected in parallel to the second switching element 262, so that the second switching element 264 is turned on less than the first switching element 262, and sequentially detects the current signal on the sensing unit 26, thereby detecting the sensing unit. Whether the current signal on 26 changes; in step S14, detecting the current signal change on the sensing unit 26, outputting the corresponding touch message, and repeating step S12.

In summary, the present invention combines the display circuit and the touch circuit, and uses the common electrode of the display system to use the AC signal as the trigger signal, so that the thickness of the overall touch display module can be thinned, so that the pursuit of modern technology is light, thin and short. trend. Furthermore, the detection mode of the present invention is that the turn-on signal is in a normal state, and the turn-off signal is in a trigger state, and the manner of detecting the current change signal is completely different from the prior art; and the voltage can be adjusted to amplify the detection signal to improve detection. Sensitivity to improve the accuracy of prior art detection accuracy.

The above is only the preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Therefore, any changes or modifications of the features and spirits of the present invention should be included in the scope of the present invention.

10‧‧‧ touch substrate

12‧‧‧ touch circuit

122‧‧‧Control circuit

124‧‧‧Signal detection circuit

126‧‧‧ drive source

14‧‧‧Sensor electrode unit

142‧‧‧TFT components

144‧‧‧Sensing 20 electrodes

16‧‧‧Control electrode line set

18‧‧‧Detection electrode line set

20‧‧‧Control electrode line

22‧‧‧Detection electrode line

24‧‧‧Color filter substrate

26‧‧‧Sensor unit

262‧‧‧First switching element

264‧‧‧Second switching element

266‧‧‧Sensor electrode

28‧‧‧Touch circuit

282‧‧‧Control circuit

284‧‧‧Signal detection circuit

30‧‧‧Display circuit

32‧‧‧Common electrode

34‧‧‧Inductive Capacitance

36‧‧‧ Passive components

FIG. 1 is a schematic diagram of a prior art thin film transistor matrix touch system.

Figure 2 is a circuit diagram of the present invention.

Figure 3 is a circuit diagram of the sensing unit of the present invention.

Figure 4 is a waveform diagram of the circuit signal of the present invention.

Figure 5 is a flow chart showing the steps of the present invention.

20‧‧‧Control electrode line

22‧‧‧Detection electrode line

24‧‧‧Color filter substrate

26‧‧‧Sensor unit

262‧‧‧First switching element

264‧‧‧Second switching element

266‧‧‧Sensor electrode

28‧‧‧Touch circuit

282‧‧‧Control circuit

284‧‧‧Signal detection circuit

30‧‧‧Display circuit

32‧‧‧Common electrode

Claims (19)

A touch system includes: a plurality of control electrode lines; a plurality of detection electrode lines interlaced with the control electrode lines; and a plurality of sensing units respectively connected to the control electrode lines and the detection electrode lines, each of the The sensing unit includes a first switching element and a second switching element connected in parallel and a sensing electrode connected to the second switching element, the sensing electrode is coupled to a common electrode, and the common electrode provides a trigger signal to the sense a measuring electrode; the control electrode line selectively outputs a closing signal to each of the first switching elements, wherein the detecting electrode line detects the sensing unit corresponding to the closing signal; and the sensing is performed when the touch is generated The electrode turns on the opening degree of the second switching element, so that the detecting electrode line detects a change of the current signal on the sensing unit, thereby obtaining at least one touch message. The touch control system of claim 1, wherein the first switching element is continuously turned on when the control electrode line does not provide the off signal, and the sensing electrode provides the trigger signal to the first The two switching elements are such that the degree of opening of the second switching element is smaller than the first switching element. The touch system of claim 1, wherein at least one of the sensing units is touched, the sensing electrode correspondingly generates a sensing capacitor, so that the voltage of the gate of the second switching element is reduced to generate Corresponding to the degree of opening, the detecting electrode line detects the current signal change on the sensing unit, thereby obtaining the touch message. The touch system of claim 1, wherein the first switching element and the second switching element are thin film transistors. The touch system of claim 1, wherein the sensing units are arranged in an array, each of the control electrode lines is respectively connected to the first switching element in the same column, and each of the detecting electrode lines is respectively connected to the same Connect the sensing units. The touch system of claim 5, wherein the gates of the first switching element and the second switching element are respectively connected to the control electrode lines and the sensing electrodes, the first switching element and the second switch The drains of the components are connected, the first switching component and the source of the second switching component are connected, and the two ends of each of the detecting electrode wires are respectively connected to the first pole of the sensing unit and the last one of the sensing electrodes The source of the sensing unit, and the drain of the sensing unit is connected in series with the source of another adjacent sensing unit. The touch system of claim 1, wherein each of the sensing units further comprises a passive component, the two ends of which are respectively connected to the gate of the first switching component and the control electrode line. The touch system of claim 7, wherein the passive component is a capacitor. The touch control system of claim 1, further comprising a touch circuit comprising a control circuit and a signal detection circuit respectively connected to the control electrode lines and the detection electrode lines, the control circuit being scanned The control electrode lines are driven to output the off signal to the first switching element line by line, and the off signal of the signal detecting circuit is corresponding to detecting the current signal change on the detecting electrode lines. The touch system of claim 1, wherein the sensing units are arranged in an array on an upper surface or a lower surface of a color filter substrate. The touch system of claim 1, further comprising a display circuit connected to the common electrode and providing the trigger signal of an alternating voltage to the sensing electrode to form a coupling relationship with the common electrode. This turns on the degree of opening of the second switching element. The touch system of claim 9, wherein the two ends of the detecting electrode lines are respectively connected to one of the power detecting end and the grounding end of the signal detecting circuit, thereby generating a voltage difference, and the detecting electrode lines are The current signal will vary depending on the magnitude of the current on the sensing unit. A touch sensing method applied to the touch system of claim 1 includes the steps of: providing the trigger signal to the sensing units, sequentially switching each of the sensing units to be turned off, and sequentially detecting the sense The current signal of the measuring unit; and detecting the current signal change, outputting the corresponding touch message, and continuously repeating the previous step of detecting the current signal of the sensing unit. The touch sensing method of claim 13, wherein the first switching element of each of the sensing units is continuously turned on when the sensing units are not switched, and each of the sensing units The sensing electrode provides the trigger signal to the second switching element connected in parallel to the first switching element, so that the second switching element is turned on less than the first switching element, and sequentially detects the sensing unit Current signal. The touch sensing method of claim 14, wherein in the step of detecting the change of the current signal, at least one of the sensing units is touched, and the sensing electrodes thereon generate a sensing capacitor correspondingly. The voltage of the gate of the second switching element connected to the sensing electrode is reduced to be corresponding to the degree of opening, and the current signal change on the sensing units is detected, that is, the output corresponds to The touch message. The touch sensing method of claim 13, wherein the sensing units are arranged in an array, and are connected to the control electrode lines and the detecting electrode lines that are staggered perpendicularly to each other, and the control electrode lines are Sequentially switching each of the sensing units to be turned off, and then sequentially passing the detecting electrode lines Corresponding to detecting the current signal of the sensing unit. The touch sensing method of claim 16, wherein the control electrode lines sequentially switch each of the sensing units in a scanning manner according to a driving of a control circuit, and sequentially detect by using a signal detecting circuit. The current signals on the detection electrode lines are measured. The touch sensing method of claim 17, wherein the signal detecting circuit detects that the current signal changes on the detecting electrode lines, that is, outputs the corresponding touch message. The touch sensing method of claim 13, wherein the trigger signal is an alternating voltage.