TWI467457B - Touch panel and driving method thereof - Google Patents

Description

Touch panel and driving method thereof

The present invention relates to an electronic device, and more particularly to a touch panel.

In order to make electronic products more user-friendly, many electronic products, such as Auto-Teller Machine (ATM), mobile phone, tablet PC, etc., have built-in touch panels. Make it easier for users to operate. In general, touch panels can be roughly classified into resistive, capacitive, infrared, and ultrasonic touch panels. Among them, resistive touch panels and capacitive touch panels are the most common products.

Taking a capacitive touch panel as an example, it is to sense and determine the position touched by the user through the X sensing series and the Y sensing series that are perpendicular to each other. In the prior art, the X sensing series and the Y sensing series belong to different film layers, and the X sensing series and the Y sensing series are separately prepared in two processes. In addition, an insulating pattern is often provided at the intersection of the X sensing series and the Y sensing series. The arrangement of the insulation pattern further increases the process complexity of the capacitive touch panel, and the production yield of the touch panel is not easily improved.

In view of this, the present invention provides a touch panel which has a simple process and high production yield.

The invention provides a driving method suitable for driving the above-mentioned touch panel with simple process and high yield.

The present invention provides a touch panel including a substrate, a plurality of sensing series disposed on the substrate, and a control unit electrically connected to the sensing series. The sensing series are parallel to each other and belong to the same film layer. The control unit inputs a driving signal for each sensing series and reads a sensing signal outputted by the sensing series adjacent to the sensing series. The control unit determines the position of the touch point based on the sensing signals.

The present invention provides a driving method. The driving method is suitable for driving a touch panel. The touch panel has a plurality of sensing series that are parallel to each other and belong to the same film layer. The driving method described includes the following steps. A driving signal is input to each sensing series and a sensing signal outputted by the sensing series adjacent to the sensing series is read. The position of the touch point is determined based on these sensing signals.

In an embodiment of the invention, the sensing series is arranged along the first direction and extends along the second direction, and the step of determining the touch point position according to the sensing signal comprises: finding all the sensing signals. At least one sensing signal different from the other sensing signals to determine the position of the touch point in the first direction; and calculating the position of the touch point in the second direction according to the sensing signal different from the other sensing signals.

In an embodiment of the invention, the step of calculating the position of the touch point in the second direction according to the sensing signal different from the other sensing signals further comprises: sensing signals different from the other sensing signals. The voltage saturation time calculates the position of the touch point in the second direction.

In an embodiment of the invention, the sensing series is divided into a plurality of sensing series groups arranged along a first direction. Each of the sensing series includes a first sensing series and a second sensing series adjacent to each other. The steps of inputting a driving signal for each sensing series and reading a sensing signal outputted by one sensing series adjacent to the sensing series are: respectively, respectively for each sensing string group Sensing the serial input driving signal and reading the sensing signal outputted by the second sensing serial of the sensing series; respectively inputting the driving signal to the second sensing serial of each sensing series and reading Sensing signals output by the first sensing series of the serialized group are sensed.

In an embodiment of the invention, the control unit comprises a multiplexer. The multiplexer inputs a driving signal for each sensing series and reads a sensing signal outputted by the sensing series adjacent to the sensing series.

In an embodiment of the invention, the multiplexer inputs a driving signal to the first sensing series of each sensing series and reads the second sensing serial output of the sensing series. Sensing signal. The multiplexer inputs the driving signals to the second sensing series of each sensing series and reads the sensing signals output by the first sensing series of the sensing series.

In an embodiment of the invention, the control unit described above comprises a calculator. The calculator calculates a plurality of capacitance change values based on the sensing signals to determine the position of the touch point.

In an embodiment of the invention, the control unit comprises an analog to digital counter. The analog to digital converter converts multiple capacitance change values into multiple digital values.

In an embodiment of the invention, the control unit comprises a central portion Processor. The central processor calculates the position of the touch point based on these digit values.

Based on the above, in the touch panel of the present invention, all the sensing series belong to the same film layer, so the touch panel of the present invention has a simple process and high production yield. In addition, the touch panel of the present invention can also realize the function of detecting the position of the touch point by using a special driving method (or a control unit). In other words, the touch panel of the present invention not only has the function of detecting the position of the touch point of the conventional touch panel, but also has the advantages of simple process and high production yield.

The above described features and advantages of the present invention will be more apparent from the following description.

FIG. 1 is a schematic diagram of a touch panel according to an embodiment of the invention. Referring to FIG. 1 , the touch panel 100 of the present embodiment includes a substrate 110 , a plurality of sensing series 122 disposed on the substrate 110 , and a control unit 130 electrically connected to the sensing series 122 . Each sensing series 122 includes a plurality of sensing pads 124 and a plurality of bridge wires 126 that are connected in series. Each bridge wire 126 connects two adjacent sensing pads 124. In the present embodiment, the shape of the sensing pad 124 is, for example, a diamond shape, and the outer shape of the bridge wire 126 is, for example, a rectangle. However, the present invention is not limited thereto, and in other embodiments, the appearance of the sensing series (including the sensing pads and the bridge wires) may be appropriately changed depending on actual needs.

With continued reference to FIG. 1, the control unit 130 of the present embodiment includes a multiplexer 132. The multiplexer 132 is configured to input a driving signal TX to each sensing series 122 and read a sensing signal RX outputted by the sensing series 122 adjacent to the sensing series 122. The control unit 130 of this embodiment further includes Calculator 134. The calculator 134 is configured to receive the sensing signal RX outputted by each sensing series 122, and calculate a capacitance change value of each point on the touch panel 100 in each frame time according to the sensing signals RX. To determine the location of the touch point. The control unit of this embodiment further includes an analog-to-digital counter 136. The analog to digital 136 is used to convert these capacitance change values into a plurality of digital values. The control unit 130 of this embodiment further includes a central processing unit 138. The central processor 138 can receive these digit values and calculate the location of the touch point based on the digit values. In addition, the central processing unit 138 can further input the position of the touch point to a picture end 140, thereby causing the picture end to perform a corresponding action.

It should be noted that in the present embodiment, all the sensing series 122 are parallel to each other and belong to the same film layer. Through the control unit 130, the sensing series 122 belonging to the same film layer can still function to detect the position of the touch point. The following is a detailed description with the illustration.

With reference to FIG. 1 , the control unit 130 of the present embodiment can input the driving signal TX to each sensing series 122 and read another sensing string adjacent to the sensing series 122 of the input driving signal TX. The sense signal RX output by column 122. In detail, in the present embodiment, all of the sensing series 122 can be divided into a plurality of sensing series groups 120 arranged along the first direction D1. Each of the sensing series 120 includes a first sensing series 122a and a second sensing series 122b adjacent to each other. In this embodiment, the control unit 130 may first input the driving signal TX to the first sensing series 122a of the first sensing series 120A and read the second sensing series of the first sensing series 120A. The sensing signal RX outputted by 122b, and then the first sensing serial group The second sensing series 122b of the 120A inputs the driving signal TX and reads the sensing signal RX output by the first sensing series 122a of the first sensing series 120A. Then, the control unit 130 can input the driving signal TX to the first sensing series 122a of the second sensing series 120B and read the second sensing series 122b of the second sensing series 120B in a similar manner. The output sensing signal RX is then input to the second sensing series 122b of the second sensing series 120B, and the first sensing series 122a of the second sensing series 120B is read. The sensed signal RX is output. The control unit 130 can sequentially input the driving signal TX and the read sensing signal RX to each sensing serial group 120 in the touch panel 100 in the above manner, thereby completing the detection of each point on the touch panel 100. action.

The control unit 130 can determine the position of the touch point according to the characteristics of the sensing signal RX. In detail, in this embodiment, the control unit 130 may first find at least one sensing signal RX of all the sensing signals RX that is different from the other sensing signals RX to determine the touch point in the first direction D1. position. Specifically, when the user touches the touch panel 100, the user's finger forms a coupling capacitance with the at least one sensing series 122 arranged along the first direction D1. The coupling capacitor converts the sensing signal RX outputted by the sensing series 122 overlapping with the user's finger, and the sensing signal RX outputted by the sensing series 122 that is not overlapped with the user's finger has different. The position of the touch point of the user's finger in the first direction D1 can be determined by finding out which sensing line RX outputs the sensed signal RX.

Then, the control unit 130 can not respond to other sensing signals according to the foregoing. The same sensing signal RX calculates the position of the touch point in the second direction D2. 2A, 2B, 3A, and 3B illustrate how the control unit 130 calculates the position of the touch point in the second direction D2 based on the sensing signal RX different from the other sensing signals.

2A illustrates a situation in which a user touches a touch point on a touch panel according to an embodiment of the present invention. 2B is an equivalent circuit diagram of FIG. 2A. Referring to FIG. 2A and FIG. 2B, when the user's finger touches the touch point A far away from the output end O, the capacitance value formed by the two sensing series 122 and the user's finger overlapping the touch point A is C _pA . The capacitance value formed by the user's finger and the touch panel 100 is C _finger . The capacitance value formed by the user's finger and the ground line is C _body . The equivalent capacitance value of the capacitance value C _finger formed by the user's finger and the touch panel 100 and the capacitance value C _body formed by the user's finger and the ground line is [(C _{body .} C _finger ) / (C _finger +C _body )]. The total equivalent capacitance value C _totalA of this equivalent capacitance value [(C _{body .} C _finger ) / (C _finger + C _body )] in parallel with the capacitance value C _pA is {[(C _body .Cfin _ger ) / (C _Finger +C _body )]+C _pA }.

FIG. 3A illustrates a situation in which a user touches another touch point on a touch panel according to an embodiment of the present invention. FIG. 3B is an equivalent circuit diagram of FIG. 3A. Referring to FIG. 3A and FIG. 3B, when the user's finger touches the touch point B which is closer to the output end O, the capacitance value of the two sensing series 122 and the user's finger overlapping with the touch point B is C _pB . The total equivalent capacitance value C _totalB of the equivalent capacitance value [(C _{body .} C _finger ) / (C _finger + C _body )] in parallel with the capacitance value C _pB is {[(C _body .C _finger )/(C _finger +C _body )]+C _pB }.

2A and FIG. 3A, the number of the sensing pads 124 between the touch point A and the output terminal O is greater than the number of the sensing pads 124 between the touch point B and the output end O, so the second sensing series The electrode area of 122 and the user's finger at the touch point A constitutes the capacitance C _pA is larger than the area of the electrode of the second sensing series 122 and the user's finger at the touch point B constituting the capacitance C _pB . The capacitance value is proportional to the electrode area, so the capacitance value C _pA formed by the second sensing series 122 and the user's finger at the touch point A is greater than the two sensing series 122 and the user finger at the touch point B. The capacitance value C _{pB is formed} . Since the capacitance value C _{pA is} greater than the capacitance value C _pB , the total equivalent capacitance value C _{totalA is} greater than the total equivalent capacitance value C _totalB in the case where the user is the same person. Therefore, the voltage saturation time of the touch point A is greater than the voltage saturation time of the touch point B. In other words, the longer the distance between the touch point and the output terminal O in the second direction D2, the longer the voltage saturation time of the touch point. With this characteristic, the control unit 130 can calculate the position of the touch point in the second direction D2. In the above manner, the control unit 130 can calculate the position of the touch point in the first direction D1 and the second direction D2, thereby detecting the correct position of the touch point.

In summary, in the touch panel of the embodiment of the invention, all the sensing series are in the same film layer. Therefore, the touch panel of the embodiment of the invention has a simple process and high production yield. In addition, the touch panel of the embodiment of the present invention can also implement the function of detecting the position of the touch point by using a special driving method (or a control unit). In other words, the touch panel of the embodiment of the present invention not only has the function of detecting the position of the touch point of the conventional touch panel, but also has the advantages of simple process and high production yield.

Although the invention has been disclosed above by way of example, it is not intended to be limiting The scope of the present invention is defined by the scope of the appended claims, and the scope of the invention is defined by the scope of the appended claims. Prevail.

100‧‧‧ touch panel

110‧‧‧Substrate

120‧‧‧Sensing tandem group

120A‧‧‧First Sensing Tandem Group

120B‧‧‧Second Sensing Tandem Group

122‧‧‧Sensor series

122a‧‧‧First sensing series

122b‧‧‧Second sensing series

124‧‧‧Sense pad

126‧‧‧Bridge wiring

130‧‧‧Control unit

132‧‧‧Multiplexer

134‧‧‧Calculator

136‧‧‧ Analog to digital device

138‧‧‧ central processor

140‧‧‧ screen side

C _pA , C _pB , C _finger , C _body ‧‧‧ capacitor

D1‧‧‧ first direction

D2‧‧‧ second direction

O‧‧‧ output

RX‧‧‧ sensing signal

TX‧‧‧ drive signal

FIG. 1 is a schematic diagram of a touch panel according to an embodiment of the invention.

2A illustrates a situation in which a user touches a touch point on a touch panel according to an embodiment of the present invention.

2B is an equivalent circuit diagram of FIG. 2A.

FIG. 3A illustrates a situation in which a user touches another touch point on a touch panel according to an embodiment of the present invention.

FIG. 3B is an equivalent circuit diagram of FIG. 3A.

100‧‧‧ touch panel

110‧‧‧Substrate

120‧‧‧Sensing tandem group

120A‧‧‧First Sensing Tandem Group

120B‧‧‧Second Sensing Tandem Group

122‧‧‧Sensor series

122a‧‧‧First sensing series

122b‧‧‧Second sensing series

124‧‧‧Sense pad

126‧‧‧Bridge wiring

130‧‧‧Control unit

132‧‧‧Multiplexer

134‧‧‧Calculator

136‧‧‧ Analog to digital device

138‧‧‧ central processor

140‧‧‧ screen side

D1‧‧‧ first direction

D2‧‧‧ second direction

O‧‧‧ output

RX‧‧‧ sensing signal

TY‧‧‧ drive signal

Claims (10)

A driving method is suitable for driving a touch panel having a plurality of sensing series parallel to each other, the sensing series belonging to the same film layer, the driving method comprising the following steps: respectively The sensing series inputs a driving signal, and reads a sensing signal outputted by the sensing series adjacent to the sensing series; and determines a position of a touch point according to the sensing signals. The driving method of claim 1, wherein the sensing series are arranged along a first direction and extend along a second direction, and determining the position of the touch point according to the sensing signals The step of: determining at least one of the sensing signals different from the other sensing signals to determine the position of the touch point in the first direction; according to different senses from other sensing signals The test signal calculates the position of the touch point in the second direction. The driving method of claim 2, wherein the step of calculating the position of the touch point in the second direction according to the sensing signal different from the other sensing signals further comprises: according to other sensing The voltage saturation time of the sensing signal different from the signal calculates the position of the touch point in the second direction. The driving method of claim 1, wherein the sensing series is divided into a plurality of sensing series groups arranged along a first direction, each of the sensing series groups being adjacent to each other a first sensing series and a second sensing series, respectively inputting the driving signal for each of the sensing series and reading the output of the sensing series adjacent to the sensing series The sensing signal The step of: inputting the driving signal to the first sensing series of each of the sensing series groups, and reading the sensing signal output by the second sensing series of the sensing series; And inputting the driving signal to the second sensing series of each of the sensing series groups, and reading the sensing signal output by the first sensing series of the sensing series. A touch panel includes: a substrate; a plurality of sensing series disposed on the substrate, the sensing series are parallel to each other and belong to the same film layer, and the sensing series is divided into a first a plurality of sensing series groups arranged in a direction, each of the sensing series groups including a first sensing series adjacent to each other and a second sensing series; and a control unit, and the sensing a series of electrical connections, the control unit respectively inputting a driving signal to each of the sensing series and reading a sensing signal outputted by the sensing series adjacent to the sensing series, the control unit is configured according to The sensing signals determine the location of a touch point. The touch panel of claim 5, wherein the control unit comprises: a multiplexer, respectively inputting the driving signal to each of the sensing series and reading adjacent to the sensing series Sensing the sensing signal outputted by the serial. The touch panel of claim 6, wherein the multiplexer inputs the driving signal to the first sensing series of each of the sensing series and reads the sensing series The sense of the second sensed serial output a dynamometer that inputs the driving signal to the second sensing series of each of the sensing series and reads the sensation of the first sensing series of the sensing series Test signal. The touch panel of claim 5, wherein the control unit further comprises: a calculator, and calculating a plurality of capacitance change values according to the sensing signals to determine a position of a touch point. The touch panel of claim 8, wherein the control unit further comprises: an analog-to-digital device, and converting the capacitance change values into a plurality of digital values. The touch panel of claim 9, wherein the control unit further comprises: a central processing unit, and calculating a position of the touch point according to the digit values.