TW201443751A - Display and touch-sensing method and device therefor - Google Patents

Abstract

A display and touch-sensing method and a device therefor are adapted to a touch display having a common electrode layer. The device operates between a display mode and touch-sensing mode by adequate allocation of the common electrode layer.

Description

Display and touch sensing method and device using the same

The present invention relates to a touch display device; in particular, to a touch display device having a common electrode layer.

Since the advent of handheld electronic devices, touch screen technology has made it convenient for users to input data and click functions. Touch screen technology has been sold by point of sale (POS), embedded computers and automatic The human-machine interface control application of devices such as the Automatic Teller Machine (ATM)... has entered the field of personal electronic products, and the popularity of a large number of personal handheld devices has become the main reason for the vigorous development of touch technology.

At present, touch panel technology can be divided into several categories: resistive, optical, electromagnetic, ultrasonic, and liquid crystal panel embedded (LCD In-Cell). Due to the booming of handheld devices, the application content is increasingly diverse and complex, and multi-touch functions and higher accuracy have become the basic requirements of today's handheld electronic devices.

The common touch screen is constructed by directly overlaying a layer of touch sensing layer on the liquid crystal panel, but this method will result in an increase in thickness, plus a combination of two transparent glass materials. Co-location can cause severe reflection of light, which can result in poor quality of the touch screen.

Nowadays, under the requirements of light, thin, short and small, the old touch screen encounters many challenges. How to reduce the thickness of the LCD touch screen will be a big issue, and the embedded touch of the liquid crystal panel The screen will be one of the priorities of future development.

The present invention provides a display and touch sensing method and a touch display device using the same.

A touch display device of the present invention comprises a common electrode layer, a thin film transistor layer and a switching unit. The common electrode layer includes a first electrode and a second electrode, and the first electrode and the second electrode form a first capacitor. The thin film transistor layer includes a third electrode and a thin film transistor. A second capacitor is formed between the third electrode and the second electrode. The thin film transistor has a gate terminal, a first end and a second end, and the second end of the thin film transistor is electrically connected to the third electrode. The switching unit has a first end and a second end. The first end of the switching unit is electrically connected to the second electrode, and the second end of the switching unit is electrically connected to the first electrode. When the switching unit is enabled, The first end of the switching unit is electrically connected to the second end of the switching unit.

A display and touch sensing method of a touch display device of the present invention includes: driving a gate line. A detection process is performed on a plurality of sensing points corresponding to the gate line. A display process is performed on a plurality of thin film transistors corresponding to the gate lines. The display and touch sensing method further includes turning off the gate line.

The detecting process includes: not enabling the plurality of switches corresponding to the plurality of sensing points to switch the touch display device to a first electrode configuration. A plurality of test signals are transmitted to the plurality of thin film transistors. Detecting a plurality of voltage values of the plurality of sensing points corresponding to the gate line. It is determined whether the plurality of voltage values are higher or lower than a predetermined range. The output is above or below the predetermined range a position of the plurality of sensing points corresponding to the plurality of voltage values.

The foregoing display program includes: enabling a plurality of switches corresponding to the plurality of sensing points to switch the touch display device to a second electrode configuration. A plurality of display signals are transmitted to the plurality of thin film transistors.

A touch display device of the present invention comprises a first substrate, a second substrate, a thin film transistor layer and a switching unit. One of the first electrode and the second electrode of the common plane are disposed on the first substrate, and a gap is formed between the first electrode and the second electrode. The thin film transistor layer is disposed on the second substrate. The switching unit has a first end and a second end. The first end of the switching unit is electrically connected to the second electrode, and the second end of the switching unit is electrically connected to the first electrode and is configured to receive a common voltage. The switching unit is enabled to turn on the first end of the switching unit and the second end of the switching unit during a display process, and is disabled during a detection procedure to disconnect the first end of the switching unit and Switching the second end of the unit.

The touch display device performs the following steps during the detection process: the plurality of switching units corresponding to the plurality of sensing points are not enabled to switch to a first electrode configuration. Transmitting a plurality of test signals to the plurality of third electrodes corresponding to the plurality of sensing points. Detecting a plurality of voltage values of the plurality of sensing points. It is determined whether the plurality of voltage values are higher or lower than a predetermined range. Finally, the positions of the plurality of sensing points corresponding to the plurality of voltage values of the predetermined range above or below the predetermined range are output.

The touch display device performs the following steps during the display process: enabling the plurality of switching units corresponding to the plurality of sensing points to switch to a second electrode configuration. And transmitting a plurality of display signals to the plurality of third electrodes corresponding to the plurality of measurement points.

It can be seen from the above that the two electrode configurations can correspond to two modes of operation respectively. When the first end of the switching unit and the second end of the switching unit are electrically connected to each other, the first electrode and the second electrode are electrically connected to form a common electrode, which is a second electrode configuration. The display device operates in the display mode, and the common electrode forms an electric field with the electrode of the corresponding thin film transistor, controls the inversion of the liquid crystal, and causes the screen to display an image.

When the switching unit is not enabled, the first electrode and the second electrode are not electrically connected. This is the first electrode configuration. At this time, the touch display device operates in the touch sensing mode, and the monitoring is performed. When the capacitance value between one electrode and the second electrode changes, it can be known whether the touch panel is touched, thereby obtaining the position touched.

The touch display device of the present invention has a structure corresponding to the display device with the touch sensing layer, and the touch sensing electrode layer portion of the present invention is an electrode layer for the common thin film transistor display. The overall thickness is thinner, and the use of multiple touch electrode layers can be avoided, thereby improving the transmittance of the liquid crystal screen.

The above description of the contents of this proposal and the following description of the implementation of the proposal are used to demonstrate and explain the spirit and principle of this proposal, and provide a further explanation of the scope of the patent application of this proposal.

100‧‧‧Touch display device

110‧‧‧Substrate

120‧‧‧thin film layer

122, 124‧‧‧film transistor unit

122a, 122b, 122c, 124a, 124b, 124c‧‧‧ film transistor

130‧‧‧Display electrode layer

132, 134‧‧‧ display electrode unit

132a, 132b, 132c, 134a, 134b, 134c‧‧‧ third electrode

140‧‧‧Liquid layer

150‧‧‧Common electrode layer

152, 152a, 152b, 152c, 152d‧‧‧ first electrode

154, 156, 158, 159‧‧‧ second electrode

152e, 152f, 152g‧‧‧ common conductive holes

154a‧‧‧first conductive hole

156a‧‧‧Second conductive hole

158a‧‧‧3rd conductive hole

159a‧‧‧4th conductive hole

154b‧‧‧first sensing point

156b‧‧‧second sensing point

158b‧‧‧ third sensing point

159b‧‧‧ fourth sensing point

160‧‧‧protective glass

170‧‧‧Switch unit

172, 192‧‧‧ first end

174, 194‧‧‧ second end

180‧‧‧ Controller

190‧‧ ‧ gate extreme

200‧‧‧Electrical hole

210‧‧‧Sensitivity

C ₁ ‧‧‧first capacitor

C ₂ ‧‧‧second capacitor

V _com ‧ ‧ common voltage node

FIG. 1 is a schematic structural view of a touch display device according to an embodiment of the present invention.

Figure 2 is a schematic cross-sectional view of Figure 1 at position 2-2.

Figure 3 is a schematic diagram of the partial equivalent circuit of Figure 2.

FIG. 4 is a schematic flow chart of an embodiment of a touch display device according to the present disclosure and a touch sensing method.

FIG. 5 is a schematic flow chart of an embodiment of a detection program according to the present disclosure and a touch sensing method.

FIG. 6 is a schematic flow chart of an embodiment of a display program according to the present disclosure and a touch sensing method.

Figure 7 is a schematic diagram of the timing operation of the touch display device of Figure 1.

Please refer to FIG. 1 and FIG. 2 together. FIG. 1 is a schematic structural view of a touch display device 100 according to an embodiment of the present disclosure. "2nd picture" is a schematic cross-sectional view of "1st picture" at position 2-2. "FIG. 1" shows the structure and circuit related to the present embodiment in a touch display device, and "2" is for the sake of convenience, only a single sensing picture in "1" is shown. The outline of the element 210 (detailed later) is schematically shown. As can be seen from FIG. 2 , the touch display device 100 includes a substrate 110 , a thin film transistor layer 120 , a display electrode layer 130 , a liquid crystal layer 140 , a common electrode layer 150 , a protective glass layer 160 , a switching unit 170 , and a control 180.

Referring to FIG. 1 , the common electrode layer 150 includes first electrodes 152 a , 152 b , 152 c , and 152 d (hereinafter collectively referred to as first electrodes 152 ), second electrodes 154 , 156 , 158 , and 159 , and conductive vias 200 . The conductive via 200 includes a first conductive via 154a, a second conductive via 156a, a third conductive via 158a, a fourth conductive via 159a, and common conductive vias 152e, 152f, 152g. The conductive vias 200 can be electrically connected to the components on the substrate 110 and the components on the common electrode layer 150 to provide functions for electrical connection between different layers. In this embodiment, the substrate 110 can be, for example, a transparent glass substrate, but is not limited thereto.

A controller 180 is disposed above the substrate 110. The controller 180 includes a first sensing point 154b, a second sensing point 156b, a third sensing point 158b, a fourth sensing point 159b, and a common voltage node _Vcom . The first sensing point 154b, the second sensing point 156b, the third sensing point 158b, the fourth sensing point 159b, and the common voltage node _Vcom are internal signal nodes of the controller 180.

The first electrode 152 can be electrically connected to the common voltage node V _com inside the controller 180 via the common conductive holes 152e, 152f and 152g. The second electrode 154 can be electrically connected to the internal node first sensing point 154b of the controller 180 via the first conductive hole 154a, and the second electrode 156 can be second sensed with the internal node of the controller 180 via the second conductive hole 156a. The second electrode 158 can be electrically connected to the internal node third sensing point 158b of the controller 180 via the third conductive hole 158a, and the second electrode 159 can be connected to the controller 180 via the fourth conductive hole 159a. The internal node fourth sensing point 159b is electrically connected.

The thin film transistor layer 120 is disposed on the substrate 110, and the thin film transistor layer 120 includes thin film transistor units 122, 124 and a display electrode layer 130. The thin film transistor units 122 each include three thin film transistors 122a, 122b, 122c, each of which includes three thin film transistors 124a, 124b, 124c, and a thin film transistor in a thin film transistor unit 122, 124. 122a, 122b, 122c, 124a, 124b, 124c may be, but not limited to, three primary colors of red, green, blue (Red, Green, Blue, RGB) in a single display pixel.

That is to say, the single thin film transistor unit 122, 124 can be regarded as a pixel (Pixel), and the single thin film transistor 122a, 122b, 122c, 124a, 124b, 124c can be a sub-pixel in a developing pixel ( Sub-Pixel). In the present embodiment, the sensing pixel 210 corresponds to two thin film transistor units 122 and 124, that is, corresponding to two pixels and six sub-pixels, but not limited thereto, one sensing pixel 210 Can correspond to one sub-pixel or more than six pixels, depending on the actual implementation of the sensing resolution, that is, when a sensing pixel 210 can When the corresponding pixel is corresponding to a sub-pixel, the resolution of the sensing will be very high. When one sensing pixel 210 can correspond to twelve sub-pixels, the resolution of the sensing will be lower.

The display electrode layer 130 includes display electrode units 132, 134, and the display electrode units 132, 134 include three third electrodes 132a, 132b, 132c, 134a, 134b, 134c (also referred to as display electrodes). The liquid crystal layer 140 is located above the display electrode layer 130, and the display electrode unit 132 and the thin film transistor unit 122 correspond to each other in a one-to-one correspondence. For example, the thin film transistor 122a corresponds to the third electrode 132a, and the thin film transistor 122b corresponds to the third electrode 132b. The common electrode layer 150 is located above the liquid crystal layer 140 for generating an electric field with the display electrode layer 130. The controller 180 controls the electric field intensity to invert the liquid crystal in the liquid crystal layer 140 to achieve the effect of liquid crystal display.

The common electrode layer 150 includes a first electrode 152 and a second electrode 154. In this embodiment, the first electrode 152 and the second electrode 154 can be disposed on a substrate (not shown). In order to more clearly show the relationship between the first electrode 152 and the second electrode 154 in the proposed touch display device, the first electrode 152 and the second electrode 154 and others are first shown in FIG. The electrodes 152 are adjacent to each other and are disposed in the same relationship as the second electrodes 156, 158, and 159. Hereinafter, for convenience of explanation, only the first electrode 152 and the second electrode 154 are used as an example, but not limited thereto. The protective glass layer 160 is disposed above the common electrode layer 150 for protecting the touch display device. The protective glass layer 160 can be, but not limited to, transparent glass or Indium Tin Oxide (ITO).

Please continue to refer to "3" and "3" is the equivalent circuit diagram of "Figure 2."

The thin film transistor 122a has a gate terminal 190, a first end 192 and a second end 194. The gate terminal 190 is electrically connected to the gate signal terminal of the controller 180 for receiving control. The first end 192 of the thin film transistor 122a is electrically connected to the data signal end of the controller 180, and the second end 194 of the thin film transistor 122a is electrically connected to the third electrode 132a. When the touch display device 100 is in the display mode (described in detail later), the controller 180 outputs the display signal to the data signal end point, and when the touch display device 100 operates in the touch sensing mode (after the device) In detail, the controller 180 outputs a test signal to the data signal endpoint.

The switching unit 170 has a first end 172 and a second end 174. The first end 172 of the switching unit 170 is electrically connected to the second electrode 154 and the first sensing point 154b electrically connected to the controller 180. The third electrode A second capacitor C ₂ is formed between the first electrode 152a and the second electrode 154. The second end 174 of the switching unit 170 is electrically connected to the first electrode 152a and the common voltage node _Vcom electrically connected to the controller 180, and the second A first capacitor C _{1 is} formed between the electrode 154 and the first electrode 152a. In the present embodiment, the switching unit 170 is a switching element or a switch in the controller 180, but is not limited thereto. The switching unit 170 may also be a separate component outside the controller 180.

When the switching unit 170 is enabled by the controller 180, the first end 172 of the switching unit 170 and the second end 174 of the switching unit 170 are electrically connected together, so that the touch display device 100 operates in the display mode, the first electrode 152a is electrically connected to the second electrode 154 to form a common electrode, which is a second electrode configuration. At this time, the first sensing point 154b inside the controller 180 is floating, and the controller 180 outputs the reference signal via The common voltage node V _{com is} to the first electrode 152a, and the reference signal can be a signal of a specific potential or ground. At the same time, the controller 180 outputs a gate signal to enable the thin film transistor 122a, that is, the first end 192 of the thin film transistor 122a and the second end 194 of the thin film transistor 122a are electrically connected together. According to the form of the thin film transistor, the gate signal can be a logic high or a low level, and the first end 192 of the thin film transistor 122a can receive the data signal output by the controller 180 ( The information signal is transmitted to the third electrode 132a via the thin film transistor 122a, so that the electric field between the third electrode 132a and the first electrode 152a and the second electrode 154 can be changed according to the change of the data signal, thereby changing The liquid crystal flip angle between the third electrode 132a and the first electrode 152a and the second electrode 154 allows the touch display to display a picture.

When the switching unit 170 is not enabled by the controller 180, the first end 172 of the switching unit 170 and the second end 174 of the switching unit 170 are not electrically connected. At this time, the touch display device 100 operates on the touch. In the sensing mode, the first electrode 152a and the second electrode 154 are not electrically connected, which is the first electrode configuration. At this time, the controller 180 detects the voltage signal of the second electrode 154 via the first sensing point 154b. The voltage signal mentioned here is the voltage division of the first capacitor C ₁ and the second capacitor C ₂ . At the same time, the controller 180 outputs a gate signal to enable the thin film transistor 122a, that is, the thin film transistor 122a is turned on. At this time, the first end 192 of the thin film transistor 122a can receive the data signal transmitted by the controller 180, and It is transferred to the first electrode 152a via the thin film transistor 122a.

That is to say, the first capacitor C ₁ and the second capacitor C _{2 are} arranged in a series configuration. When an object that changes the capacitance value, such as a finger, a stylus pen, or the like, approaches the first electrode 152a and the second electrode 154, the object affects the capacitance of the first capacitor C ₁ between the first electrode 152a and the second electrode 154. The magnitude of the value, the intermediate node voltage of the first capacitor C ₁ and the second capacitor C _{2 in} series changes, and the controller 180 can determine the first electrode 152a according to the sensing signal detected by the first sensing point 154b. Whether the second electrode 154 is touched or not, and thus the coordinates of the touched position.

The present invention also proposes a display and touch sensing method for a touch display device. Please refer to "Fig. 4", which is a display of the touch display device according to the present proposal. A schematic flowchart of an embodiment of a touch sensing method. The method of the present proposal includes: driving a gate line (step S400). A detection process is performed on the plurality of sensing points corresponding to the gate line (step S410). And displaying a plurality of thin film transistors corresponding to the gate lines (step S420). The display and touch sensing method further includes turning off the gate line (step S430).

For the gate line, please refer to "FIG. 3". The touch display device 100 includes a plurality of gate lines and data lines, and the gate lines and the data lines are arranged in a crisscross manner. Each of the gate lines corresponds to the plurality of thin film transistors 122a, and is electrically connected to the gate terminal 190 of the corresponding thin film transistor 122a, and each of the data lines also corresponds to the plurality of thin film transistors 122a, and is electrically connected to the gate electrode The first end 192 of the corresponding thin film transistor 122a may be a source, but is not limited thereto. When the touch display device 100 displays an image, the touch display device 100 can sequentially drive each gate line, and each thin film transistor 122a of the corresponding gate line in the time interval for driving each gate line. The first end inputs the imaging material to form an image.

Please refer to "Fig. 3" and "Fig. 7". First, when the gate line is driven in step S400, the controller 180 outputs a gate signal ("the first gate signal shown in Fig. 7"). The gate terminals 190 of the plurality of thin film transistors 122a corresponding to the gate lines are controlled such that the thin film transistors 122a are turned on (even if the first ends 192 of the thin film transistors 122a are electrically connected to the second ends 194 of the thin film transistors 122a).

Next, the controller 180 performs a detection process on the first sensing point 154b corresponding to the gate line (step S410). For the detection procedure, please refer to "figure 5" and "figure 3" at the same time. FIG. 5 is a schematic flow chart of an embodiment of a detection program according to the present disclosure and a touch sensing method.

The detecting program includes: notifying the plurality of switches corresponding to the plurality of sensing points to switch to the first electrode configuration (step S500). A plurality of test signals are transmitted to the plurality of thin film transistors (step S510). A plurality of voltage values of the plurality of sensing points corresponding to the gate line are detected (step S520). It is judged whether or not the aforementioned plurality of voltage values are higher or lower than a predetermined range (step S530). Finally, the positions of the plurality of sensing points corresponding to the plurality of voltage values that are higher or lower than the predetermined range are output (step S540).

Regarding step S500, the controller 180 does not enable the first sensing point 154b (hereinafter, the first sensing point 154b is taken as an example, but is not intended to limit the scope of the proposal), that is, the foregoing switching unit 170 In order to switch the touch sensing device 100 to the first electrode configuration, the first electrode configuration is a state in which the first electrode 152a and the second electrode 154 are not electrically connected. At this time, the touch display device 100 operates in touch sensing mode.

In step S510, the controller 180 transmits a test signal to the first end 192 of the thin film transistor 122a corresponding to the gate line. Connection, the controller 180 detects a first gate line corresponding to the sensed voltage value of the point 154b (step S520), the voltage value of the capacitor C of the first line is a second voltage capacitor C ₁ and ₂ partial pressure, the voltage on this The principle of partial pressure has been explained in the previous section and will not be described again.

When the step S530 is performed, the controller 180 determines whether the detected voltage value is higher or lower than a predetermined range, and the predetermined range may be preset. The predetermined range may be determined by referring to the second electrode 154 being touched or not. The value of the voltage when touched is determined. Further, the voltage of the second electrode 154 of the plurality of sensing pixels that is not touched is collected, and the average value or the mode is collected. Then, the first plurality of sensing pixels are collected. The voltage value of the two electrodes 154 being touched is averaged or modest, and then the predetermined range of voltage values that are touched and untouched can be set accordingly.

Thereafter, in step S540, the controller 180 can output the position of the first sensing point 154b corresponding to the voltage value higher or lower than the predetermined range, and further know the coordinates of the touched position.

For the display procedure described in the foregoing step S420, please refer to "FIG. 6", which is a schematic flowchart of an embodiment of a display program according to the present disclosure and a touch sensing method. The display program includes: enabling a plurality of switches corresponding to the plurality of sensing points to switch to the second electrode configuration (step S600). And transmitting a plurality of display signals to the plurality of thin film transistors (step S610).

In the step S600, the controller 180 enables the switch corresponding to the first sensing point 154b to switch the touch display device 100 to the second electrode configuration. The second electrode configuration has been described above and will not be described again. At this time, the touch display device 100 operates in the display mode, the first electrode 152a and the second electrode 154 are electrically connected to form a common electrode, the first sensing point 154b of the controller 180 does not operate, and the controller 180 outputs the reference signal via The common voltage node V _{com is} connected to the first electrode 152a and the second electrode 154.

In the display mode, the controller 180 transmits a display signal to the first end 192 of the thin film transistor 122a corresponding to the gate line (ie, the end connected to the data line) (step S610), so that the data signal is transmitted through the thin film transistor. 122a is transmitted to the third electrode 132a, so that the electric field between the first electrode 152a and the second electrode 154 can change the liquid crystal flip angle between the first electrode 152a and the second electrode 154 according to the data signal change, so that the touch display display screen .

The touch display device of the present invention is controlled by a time division driving signal outputted by the controller 180, as shown in "Fig. 7", and "Fig. 7" is a "1st image" touch display. Schematic diagram of the timing operation of the device. Please also refer to "Figure 3" for time-sharing One operation cycle includes a display driving time period and a touch sensing time period. One of the operating cycles is the first gate signal line enable condition, in this embodiment, that is, the time period when the first gate signal is at the logic high voltage level. The length of time of a single operation time period is approximately equal to the length of time that the touch display device 100 drives a single gate line.

The switching signal in "Figure 7" is the signal that the switching unit 170 is enabled and disabled. When the touch sensing period (the time period during which the detection program is executed), the switching signal is logic low. At this time, the switching unit 170 is not enabled, and the first end 172 of the switching unit 170 is not electrically connected to the second end 174 of the switching unit 170, and the touch display device 100 is in the first electrode configuration. When the display driving period (ie, the time period during which the program is executed) is displayed, the switching signal is at a logic high level, at which time the switching unit 170 is enabled, the first end 172 of the switching unit 170 and the second end 174 of the switching unit 170. Electrically connected, the touch display device 100 is in a second electrode configuration.

During an operation cycle of the time-sharing driver, the detection program can be executed before the display program, or the display program can be executed before the detection program. In order to ensure the detection result and the display screen are correct, the detection program and the detection program The time ratio of the display program can be 1:9, but not limited to this.

In summary, the touch display device technology of the present disclosure can be applied to a general liquid crystal display architecture. The touch display device can simultaneously switch between two electrode configurations of the common electrode layer, so that the touch display device can simultaneously LCD display and touch sensing function.

100‧‧‧Touch display device

122a‧‧‧film transistor

132a‧‧‧third electrode

140‧‧‧Liquid layer

152a‧‧‧first electrode

154‧‧‧second electrode

154b‧‧‧first sensing point

170‧‧‧Switch unit

172, 192‧‧‧ first end

174, 194‧‧‧ second end

180‧‧‧ Controller

190‧‧ ‧ gate extreme

C ₁ ‧‧‧first capacitor

C ₂ ‧‧‧second capacitor

V _com ‧ ‧ common voltage node

Claims (10)

A touch display device includes: a common electrode layer including a first electrode and a second electrode, wherein the first electrode and the second electrode form a first capacitor; and a thin film transistor layer, comprising: a third electrode, a second capacitor is formed between the third electrode and the second electrode; and a thin film transistor having a gate terminal, a first end and a second end, the film transistor The second end is electrically connected to the third electrode; and a switching unit has a first end and a second end, the first end of the switching unit is electrically connected to the second electrode, and the switching unit The second end is electrically connected to the first electrode, and the first end of the switching unit is electrically connected to the second end of the switching unit when the switching unit is enabled. A display and touch sensing method of a touch display device includes: driving a gate line; performing a detection process on the plurality of sensing points corresponding to the gate line; and corresponding to the gate line The thin film transistor performs a display procedure. The display of the touch display device of claim 2 and the touch sensing method further include turning off the gate line. The display and touch sensing method of the touch display device of claim 2, wherein the detecting program comprises: Not controlling the plurality of switches corresponding to the sensing points to switch to a first electrode configuration; transmitting a plurality of test signals to the thin film transistors; detecting the plurality of sensing points corresponding to the gate lines a voltage value; determining whether the voltage values are higher or lower than a predetermined range; and outputting the positions of the sensing points corresponding to the voltage values above or below the predetermined range. The display and touch sensing method of the touch display device of claim 2, wherein the display program comprises: enabling a plurality of switches corresponding to the sensing points to switch to a second electrode configuration; Display signals to the thin film transistors. The display and touch sensing method of the touch display device of claim 2, wherein the gate line is electrically connected to the plurality of gate terminals of the thin film transistors, and each of the thin film transistors has a gate terminal and a first The first end of the thin film transistor is configured to receive a test signal or a display signal, and each switch has a first end and a second end, and the second end of the switch is electrically Connecting a reference signal and a first electrode, the first end of the switch is electrically connected to the sensing point and a second electrode, and the second end of the thin film transistor is electrically connected to a third electrode, A first capacitor is formed between the first electrode and the second electrode, and a second capacitor is formed between the second electrode and the third electrode. The display and touch sensing method of the touch display device of claim 2, wherein the ratio of the time between the detection program and the display program is 1:9. A touch display device comprising: a first substrate; a first electrode and a second electrode are disposed on the first substrate, and a gap is formed between the first electrode and the second electrode; a second substrate; a thin film a switching layer is disposed on the second substrate; and a switching unit has a first end and a second end, the first end of the switching unit is electrically connected to the second electrode, and the second end of the switching unit The terminal is electrically connected to the first electrode and is configured to receive a common voltage; wherein the switching unit is enabled during a display process to turn on the first end of the switching unit and the second end of the switching unit, And being disabled during a detection procedure to disconnect the first end of the switching unit and the second end of the switching unit. The touch display device of claim 8, wherein the first electrode and the second electrode receive the common voltage and the potentials of the first electrode and the second electrode are substantially the same during the display process. The touch display device of claim 9, wherein the touch display device performs the following steps: not enabling the plurality of sensing units corresponding to the plurality of sensing points to switch to a first electrode group Transmitting a plurality of test signals to the plurality of third electrodes corresponding to the sensing points; detecting a plurality of voltage values of the sensing points; determining whether the voltage values are higher or lower than a predetermined range; Outputting the sensing points corresponding to the voltage values above or below the predetermined range Positioning; and during the displaying process, the touch display device performs the steps of: enabling the switching units corresponding to the sensing points to switch to a second electrode configuration; and transmitting a plurality of display signals to The sensing electrodes correspond to the third electrodes.