CN101539828B - Device and method for judging positions of multiple contacts on projective capacitive touch panel - Google Patents

Abstract

The invention discloses a device and a method for judging positions of multiple contacts on a projective capacitive touch panel. When a large current is detected on an X sensing strip, the X sensing strip is judged whether only one contact or more than one contact is present on the X sensing strip according to the magnitude of the current on the X sensing strip, and Y coordinates of more than one contact on the X sensing strip are recorded firstly. Then, the current on all the Y sensing bars is sensed, and the X coordinate of more than one contact on the X sensing bar can be judged by referring to the X and/or Y coordinate X, Y information of all the contacts which are directly obtained in advance.

Description

Device and method for determining the position of multiple touch points on a projected capacitive touch panel

technical field

The present invention relates to a device and method for the position of multiple touch points on a touch panel, in particular to a device and method for determining the position of multiple touch points on a projected capacitive touch panel.

Background technique

Traditionally, the input of electronic devices is performed by keyboard and mouse, which cannot be performed in a way of human intuition. After that, the touch panel has been widely used in various large and small electronic devices. At this time, the user can touch the upper panel of the electronic device with a hand or a stylus to perform contact input. The sensing device arranged under the control panel senses the position of the touch point, so as to realize the purpose of operating the touch electronic device. Divided by the sensing mechanism of sensing contact input, touch panels can be classified into resistive, capacitive, acoustic, optical and electromagnetic touch panels; divided by the types of touch panels, which also include touch Panels and touchpads and other categories.

Nowadays, there is also a technology of multi-touch acting on the touch panel to perform functional input on it, so that users can use electronic devices with a touch panel more conveniently, so the judging technology of the position of the multi-touch must also be corresponding Been proposed.

As far as the capacitive touch panel is concerned, the sensing device senses the position of the touch point by sensing the change of the equivalent capacitance value at the touch point, which will be described as follows, wherein the capacitive touch panel The panel usually uses the user's finger as the input medium, and generally does not use a stylus, because the finger is a conductive medium and can change the equivalent capacitance value at the contact point.

FIG. 1A is an exploded perspective view of a conventional projected capacitive touch panel. As shown in FIG. 1A, the capacitive touch panel 10 is formed in the same shape from bottom to top by a transparent substrate 11, an X transparent sensing layer 12, a transparent dielectric layer 13 and a Y transparent sensing layer 14, wherein X There is a sensing pattern 15 on each of the Y transparent sensing layers 12, 14, which is used to cooperate with other components to determine the existence of one or more contacts on the panel 10, wherein the sensing pattern 15 is connected to a plurality of external wires 19. Then, it will be explained below.

1B and 1C are schematic diagrams of the sensing patterns 15 on the X and Y transparent sensing layers 12 and 14 of the projected capacitive touch panel shown in FIG. 1A respectively, and FIG. 1D is the capacitive touch panel shown in FIG. A schematic diagram illustrating a top view of the touch panel 10 via the sensing pattern 15 overlapping the X and Y transparent sensing layers 12 , 14 .

As shown in FIG. 1B, FIG. 1C and FIG. 1D, the sensing pattern 15 includes a plurality of X sensing strips 151 and a plurality of Y sensing strips 152, and each of the above-mentioned X sensing strips 151 is made of a plurality of X conductive strips. Wire diameter 16 and a plurality of sensing boards 18, and each of the above-mentioned Y sensing strips 152 is composed of a plurality of Y conductive wire diameters 17 and a plurality of sensing boards 18, wherein the sensing boards 18 are connected periodically Between the above-mentioned adjacent X and Y conductive wire diameters 16 , 17 . The sensing pattern 15 is arranged under a glass plate (not shown) of the touch panel 10, and forms a sensing device 20 of the panel 10 together with the plurality of external wires 19 and a sensing voltage source 21, and The external wires 19 are respectively disposed between the sensing voltage source 21 and the corresponding X and Y conductive wires 16 , 17 .

In actual operation, the sensing voltage source 21 sequentially supplies an AC sensing voltage Vs to each X conductive wire diameter 16, and then sequentially supplies the sensing voltage Vs to each Y conductive wire diameter 17, in this way Sensing a touch position P of the user on the glass panel will be described below, wherein the glass plate is where the user's finger actually touches.

There is a capacitive effect between the X and Y sensing bars 151 , 152 and the glass panel, and there is another capacitive effect between them and a virtual ground (not shown). When the user's finger touches a point P on the glass panel, the contact point brings a capacitive effect on the X and Y conductive wire diameters 16, 17, so an equivalent capacitance value under the contact point P is changed. The sensing voltage Vs generates a corresponding current I on each of the X and Y sensing bars 151 , 152 when sensing the variation of the equivalent capacitance. At this time, a current detection unit (not shown) is used to sense the change of the current I to determine the position of the contact P on the glass panel, because the change of the current I corresponds to the change of the equivalent capacitance .

When multiple touch points are input, the projected capacitive touch panel cannot fully determine the positions of the multi-touch points, which will be described later with reference to FIG. 2 . FIG. 2 is a schematic diagram illustrating the structure of a conventional projected capacitive touch panel with multiple contacts, the structure of which is the same as that shown in FIG. 1A , FIG. 1B and FIG. 1C . As shown in Figure 2, a contact P1 (x1, y1) and a contact P2 (x2, y2) form a first contact group, a contact P3 (x1, y2) and a contact P4 (x2, y1) form a second contact group. When the sensing voltage Vs is respectively and alternately sent to the X and Y conductive wire diameters 16, 17, the four coordinate values x1, x2, y1, y2 are obtained, at this time (x1, x2, y1, y2) four X or Y The coordinate values can form four position coordinates (x, y), so whether the two touch points input by the user on the projected capacitive touch panel 10 are the first point group or the second point group cannot be distinguished.

In view of the above reasons, it is necessary to propose a device and method for determining the position of multiple touch points on a projected capacitive touch panel, so as to realize its application in multi-touch control.

Contents of the invention

In view of the problems in the prior art, an object of the present invention is to provide a device for determining the positions of multiple touch points on a projected capacitive touch panel, so as to overcome the disadvantages of the prior art.

Another object of the present invention is to provide a method for determining the positions of multiple touch points on a projected capacitive touch panel, so as to overcome the disadvantages of the prior art.

In the device for determining the position of multiple contacts on a projected capacitive touch panel of the present invention, the projected capacitive touch panel includes a transparent substrate, a Y transparent sensing layer, a A transparent dielectric layer and an X transparent sensing layer, the X transparent sensing layer has a plurality of X sensing strips arranged along an X direction, and has a first X side and a second X side in the X direction , the Y transparent sensing layer has a plurality of Y sensing strips arranged along a Y direction, and has a first Y side and a second Y side in the Y direction, and the multi-contact makes the X transparent sensing layer is in contact with the Y transparent sensing layer at the multi-contact position, and the sensing device includes a plurality of X external wires and a plurality of Y external wires, a sensing source, a current sensing unit, and a current comparison unit 1. A contact number determination unit, a first coordinate determination unit, a second coordinate determination unit and a position coordinate determination unit. The plurality of X outer connecting wires and the plurality of Y outer connecting wires are respectively used to electrically connect the plurality of X and Y sensing strips along the first and second X sides and the first and second X sides in a one-to-one relationship. Two Y side. The sensing source is used to sequentially provide an AC sensing voltage to the plurality of X sensing strips on the first X side and the second X side through the plurality of X external wires, and then sequentially through the plurality of Y The external lead wire provides the AC sensing voltage to the plurality of Y sensing strips on the first Y side and the second Y side, so that at least one group of the plurality of X and Y sensing strips can be activated when the multi-contact occurs. At least one X current pair is formed on the corresponding X sensing strips, and at least one Y current pair is formed on at least one corresponding Y sensing strip, wherein each of the at least one corresponding X current pair includes at least one An X current pair, and each of the at least one X current pair has a first and a second X partial current, and the first and second X partial currents are the corresponding X of the multi-contact At least one contact on a corresponding one of the sensing strips is spaced apart, and the first X partial current is formed when at least one of the multi-contacts is more than one contact on the corresponding X sensing strip Between the first X-side and one of the more than one contacts that is closer to the first X-side, the second X partial current is formed between the second X-side and one of the more than one contacts closer to the second X side, and at least one of the at least one corresponding Y current pair group includes at least one Y current pair, and each of the at least one Y current pair has a first and a second Y partial current, and the first and second Y partial currents are separated by at least one contact of the multi-contact on a corresponding one of the corresponding Y sensing strips, and when the multi-contact When at least one of the corresponding Y sensing strips is more than one contact, the first Y partial current is formed on the first Y side and one of the more than one contacts that is closer to the first Y side In between, the second Y partial current is formed between the second Y side and one of the more than one contacts that is closer to the second Y side. The current sensing unit is used to sequentially sense an X current and a Y current on each of the X and Y sensing bars on the first and second X and Y sides respectively, so as to respectively obtain the at least one The set of X current pairs and the at least one set of Y current pairs are used to determine the first and second partial X currents of each of the at least one X current pair and the first and second partial currents of each of the at least one Y current pair. The first and second Y partial currents of the two Y current pairs, and respectively determine a maximum first and second X partial current of the first and second X partial currents and a maximum of the first and second Y partial currents A maximum first and second Y partial current, and the maximum first and second X and Y currents are taken as a first and second X and Y current, respectively. The current comparison unit is used to respectively compare the first and second X currents with a first and second X reference current, and then respectively compare the first and second Y currents with a first and second Y reference current , to obtain a current change amount of the first and second X and Y currents respectively; the contact number determination unit is used to determine whether the current change amounts of the first and second X currents are greater than a first critical value respectively Whether there is more than one contact on the X sensing bar corresponding to the first and second X currents, and respectively according to whether the change amount of the first and second X currents is less than the first critical value but greater than a first threshold value Two critical values determine the existence of only one single contact on the X sensing bar corresponding to the first and second X currents, and judge according to whether the change amount of the first and second Y currents is greater than a first critical value Whether there is more than one contact on the Y sensing strip corresponding to the first and second Y currents, and respectively according to whether the change amount of the first and second Y currents is less than the first critical value but greater than a first critical value Two critical values determine that there is only one single contact on the Y sensing strip corresponding to the first and second Y currents; the first coordinate determining unit is used to determine that it is determined to be on the corresponding X sensing strip having the y-coordinates of the positions of the more than one touch points, and determining the x- and y-coordinates of the positions determined to be single touch points on the corresponding X-sensing strip. The second coordinate determining unit is used to determine the X coordinate x and Y coordinate y of the single contact determined to be on the corresponding Y sensing strip, and according to the determined on the corresponding X sensing strip X and Y coordinates x, y of a single contact, Y coordinate y of more than one contact on the corresponding X sensing strip, and single contact and more than one contact on the corresponding Y sensing strip Determine the X and Y coordinates x, y of each contact position of more than one contact on the corresponding X sensing strip with the x and y coordinates of the corresponding X sensing strip, and more than one touch point on the corresponding X sensing strip that has been determined The Y coordinate y of the contact position of a contact is reconfirmed. The position coordinate determining unit is used to match the x and y coordinates of the single touch point and more than one touch point on the corresponding X and Y sensing strips to determine the position of the multi-touch points.

In the method for determining the position of multiple contacts on a projected capacitive touch panel of the present invention, the projected capacitive touch panel includes a transparent substrate formed in the same shape and stacked up sequentially, a Y transparent sensing layer, a A transparent dielectric layer and an X transparent sensing layer, the X transparent sensing layer has a plurality of X sensing strips arranged along an X direction, and has a first X side and a second X side in the X direction , the Y transparent sensing layer has a plurality of Y sensing strips arranged along a Y direction, and has a first Y side and a second Y side in the Y direction, and the multi-contact makes the X transparent sensing layer is in contact with the Y transparent sensing layer at the multi-contact position, and multiple X external wires and multiple Y external wires are used to electrically connect the multiple X and Y sensing wires in a one-to-one relationship, respectively. along the first and second X sides and the first and second Y sides; sequentially provide an AC sensing voltage to the first X side and the second X side through the plurality of X external wires X sensing strips, and then sequentially provide the AC sensing voltage to the multiple Y sensing strips on the first Y side and the second Y side through the multiple Y external wires, so as to appear on the multi-contact At least one X current pair is formed on at least one corresponding X sensing strip of the plurality of X and Y sensing strips, and at least one Y current pair is formed on at least one corresponding Y sensing strip, Each of the at least one corresponding X current pair group includes at least one X current pair, and each of the at least one X current pair has a first and a second X partial current, and the first and second The X partial currents are all separated by at least one contact of the multi-contact on a corresponding one of the set of corresponding X-sensing strips, and when at least one of the multi-contacts is on the corresponding X-sensing strip When there is more than one contact, the first X partial current is formed between the first X side and one of the more than one contacts closer to the first X side, and the second X partial current is formed between the second X side and one of the more than one contacts that is closer to the second X side, and at least one of the at least one corresponding set of Y current pairs includes at least one Y current pair, and the at least one Each of the Y current pairs has a first and a second Y partial current, and the first and second Y partial currents are both on a corresponding one of the multi-contact on the set of corresponding Y-sense bars and when at least one of the multi-contacts is more than one contact on the corresponding Y sensing strip, the first Y partial current is formed between the first Y side and the multi-contact between a contact closer to the first Y side, the second Y partial current is formed between the second Y side and one of the more than one contacts closer to the second Y side Between; respectively sense an X current and a Y current on each of the X and Y sensing strips in order to respectively obtain the at least one set of X current pairs and the at least one set of Y current pairs, and determine respectively The first and second X partial currents of each of the at least one X current pair, and the first and second Y partial currents of the first and second Y current pairs of each of the at least one Y current pair, and respectively determining a maximum first and second X partial current among the first and second X partial currents and a maximum first and second Y partial current among the first and second Y partial currents, and the maximum The first and second X and Y currents are taken as a first and second X and Y current respectively; the first and second X currents are compared with a first and second X reference current respectively, and then the first and second X reference currents are compared respectively One and second Y currents and one first and second Y reference currents to obtain a current change amount of the first and second X and Y currents respectively; according to the current change amounts of the first and second X currents respectively Whether it is greater than a first critical value determines whether there is more than one contact on the X sensing strip corresponding to the first and second X currents, and respectively according to whether the change amount of the first and second X currents is less than the The first critical value but greater than a second critical value determines that there is only a single contact on the X sensing strip corresponding to the first and second X currents, and respectively according to the change amounts of the first and second Y currents Whether it is greater than a first critical value determines whether there is more than one contact on the Y sensing strip corresponding to the first and second Y currents, and respectively according to whether the change amount of the first and second Y currents is less than the The first critical value but greater than a second critical value determines that there is only a single contact on the Y sensing strip corresponding to the first and second Y currents; it is determined that it is determined to have a single contact on the corresponding X sensing strip. The y coordinates of the position of the more than one contact point, and determine the x and Y coordinates of the position of the single contact point that is determined to be on the corresponding X sensing strip; determine the position that is determined to be on the corresponding Y sensing strip X-coordinate x and Y-coordinate y of the single contact on the corresponding X-sensing strip, and according to the X- and Y-coordinates x, y of the single-contact on the corresponding X-sensing strip, the corresponding X-sensing strip The Y coordinate y of more than one contact, and the x and y coordinates of single contact and more than one contact on the corresponding Y sensing strip determine the more than one contact on the corresponding X sensing strip The X and Y coordinates x, y of each contact position of each contact point, and confirm again the Y coordinate Y of the contact position Y of more than one contact point on this corresponding X sensing strip; And match this corresponding X and The x and y coordinates of a single touch point and more than one touch point on the Y sensing strip are used to determine the position of the multi-touch point.

By using the present invention, the positions of the multi-touch points can be completely determined on the projected capacitive touch panel, so that this kind of touch panel can be formally used for multi-touch function touch control.

The above summary and subsequent detailed descriptions and drawings are all for further explaining the technical solutions, technical means and effects adopted by the present invention to achieve the purpose of the invention, and are not intended to limit the present invention.

Description of drawings

The description of the preferred embodiment of the invention is given by the following drawings, in which:

FIG. 1A is a three-dimensional exploded view of a conventional projected capacitive touch panel;

1B and 1C are schematic diagrams of sensing patterns on the projected capacitive touch panel shown in FIG. 1A ;

FIG. 1D is a schematic diagram illustrating the top view of the sensing patterns in FIG. 1B and FIG. 1C after overlapping; and

FIG. 2 is a schematic diagram illustrating a top view of the conventional projected capacitive touch panel shown in FIG. 1A when there are multiple contacts;

3 is a three-dimensional exploded view of the projected capacitive touch panel of the present invention;

4 is a functional block diagram of a projected capacitive touch panel of the present invention;

5 is a schematic diagram illustrating multi-contact position determination of the projected capacitive touch panel of the present invention; and

FIG. 6 is a flowchart of a method for determining the positions of multiple touch points on a projected capacitive touch panel of the present invention.

Among them, reference signs:

10 Projected capacitive touch panel 11 X transparent substrate

12 X Transparent Sensing Layer 13 Transparent Dielectric Layer

14 Y transparent sensing layer 15 Sensing pattern

16 X conductive wire diameter 17 Y conductive wire diameter

18 Sensing board 19 External wire

20 Sensing device 21 Sensing voltage source

151 X sensing strip 152 Y sensing strip

31 Substrate 32 X transparent sensing layer

33 Transparent dielectric layer 34 Y transparent sensing layer

35 sensing patterns 36 X sensing strips

37 Y sensing strip 40 Position judging device

41 External wire unit 42 Sensing source

43 Current sensing unit 44 Current comparison unit

45 Contact number determination unit 46 First coordinate determination unit

47 Second coordinate judging unit 48 Position coordinate judging unit

51 Sensing source 59 External wire

Detailed ways

The present invention is a device and method for determining the position of multiple touch points on a projected capacitive touch panel, which will be described in detail as follows through preferred embodiments and accompanying drawings.

Please refer to FIG. 3 , which is an exploded perspective view of the projected capacitive touch panel of the present invention. As shown in FIG. 3 , the projected capacitive touch panel 30 includes a transparent substrate 31 , an X transparent sensing layer 32 , a transparent dielectric layer 33 and a Y transparent sensing layer formed in the same shape and stacked up sequentially. 34, which is the same as the traditional projected capacitive touch panel, wherein there is a sensing pattern 37 on the X transparent sensing layer 32 and the Y sensing layer 34, and the sensing pattern 37 is connected with an external wire 59 , which will be explained below.

Please refer to FIG. 4 , which is a functional block diagram of the device for determining the positions of multiple touch points on the projected capacitive touch panel of the present invention.

As shown in Figure 4, the device 40 includes an external wire unit 41, a sensing source 42, a current sensing unit 43, a current comparison unit 44, a contact number determination unit 45, a first coordinate determination unit 46, a The description of the respective functions of the second coordinate determining unit 47 and a position coordinate determining unit 48 will be provided later.

FIG. 5 is a top schematic explanatory diagram of the device for determining the position of multiple touch points on a projected capacitive touch panel of the present invention when there are multiple touch points thereon.

As shown in FIGS. 4 and 5 , the device 50 includes a plurality of X sensing strips 35 arranged along the X direction on the X transparent sensing layer 32 of the projected capacitive touch panel 30 and the Y transparent sensing layer 34 There are a plurality of Y sensing strips 36 arranged along the Y direction. The X sensing strips 35 and the Y sensing strips 36 are collectively referred to as a sensing pattern 37 . The projected capacitive touch panel 30 has two X sides X1 and X2 in the X direction, and has two Y sides Y1, Y2 in the Y direction, wherein the X and Y sensing strips 35, 36 are the same as those shown in FIG. 1B and FIG. The X and Y sensing bars 151 and 152 shown in 1C are the same, and are only represented by two X and Y sensing bars 35 and 36 related to the description of the embodiment of the present invention. When the multiple contacts P1, P2 (take two points as an example) appear on the panel 30, the X transparent sensing layer 32 and the Y transparent sensing layer 34 are at the positions of the multiple contacts P1, P2 contacts (not shown).

Firstly, a plurality of X and Y external wire units 41 are firstly provided, and are respectively connected to the above-mentioned X sensing strips 35 and Y sensing strips 36 in a one-to-one relationship.

Next, the sensing source 42 first provides an AC sensing voltage Vs to the X sensing strips 35 on the two X sides X1 and X2 through the corresponding external wires 59, and then provides an AC sensing voltage Vs to the Y sensing bars 35 on the two Y sides Y1 and Y2. The bar 36 provides the AC sensing voltage Vs to form a current I at the relevant place between the X sensing bar 35 and at least one of the above-mentioned contacts P1, P2, and then at the relevant place of the Y sensing bar 36 and the above-mentioned contact P1. , At least one of the correlations of P2 forms a current I.

In fact, when a contact P1 or P2 is stored on the X and Y sensing strips 35, 36, the current I is formed into a first part of the current and a second part of the current I, because the contacts can connect X and Y to each other. The current I on the Y sensing strips 35, 36 is conducted to the ground, so the first and second part of the current I respectively flow from the two X sides X1, X2 and the two Y sides Y1, Y2 to the contact P1 or P2 to the ground. , the first and second partial currents I are referred to as a current pair here. If the number of contacts P1 and P2 on at least one of the above-mentioned contacts P1 and P2 related to the X and Y sensing strips 35 and 36 is more than one, the corresponding current I is also divided into the first and the first ones. The second part current I, because the judgment of the multi-contact position of the present invention is only related to the current I of the contact point P1, P2 and two X sides X1, X2 and two Y sides Y1, Y2, so in two or more The current on the path sandwiched between contacts P1 and P2 can be ignored.

In fact, a single contact can form a group of X current pairs and a group of Y current pairs, because a single contact may press more than one X and Y sensing strips 35, 36, so all corresponding to a single contact The X and Y currents on the pressed X and Y sensing bars 35 and 36 constitute a pair of X and Y currents respectively. When multiple contacts exist, the number of formed X and Y current pairs is greater than one. In fact, the X and Y current pair on an X and Y sensing strip 35, 36 closest to the center of the user's finger will have a maximum X and Y current I, respectively.

In fact, the X and Y sensing strips 35, 36 without contacts pressed thereon do not exist without current, because each of the X and Y sensing strips 35, 36 is relative to other elements of the touch panel 30 and the external environment. There is a capacitive effect between them, so although the same sensing voltage Vs is applied to the two Y sides Y1 and Y2, the X and Y sensing bars 35 and 36 that are not pressed by the contacts may still have current.

Please return to FIG. 4 and FIG. 5, and then, the current sensing unit 43 respectively senses the above-mentioned X and Y current pair groups, and respectively senses the maximum X current pair in each group of these X and Y current pair groups. and the maximum Y current pair, and further sense the first and second X current pair and the first and second Y current pair. The X and Y sensing bars 35 , 36 corresponding to the maximum X current pair and the maximum Y current pair are used as the basis for determining the positions of the contacts, which will be further described below.

Next, the current comparison unit 44 compares the first and second X currents corresponding to each contact with a first X and second X reference current (not shown), so as to sequentially obtain these first and second X currents. A current change amount ΔI of the current I. In a preferred embodiment, the first and second X reference currents are the currents I corresponding to the X sensing bar 35 on the two X sides X1 and X2 before a corresponding one of the multi-contacts P1 and P2 appears. Similarly, a current variation ΔI of the first and second Y current I can also be obtained, and the first and second Y reference currents are also given in a similar manner.

The contact number determination unit 45 is used to first determine whether there is more than one contact on the X sensing bar 36 ; that is, to determine whether the y coordinates of the multi-contacts P1 and P2 are the same.

On a single X sensing bar 35 , since the presence of a contact reduces the impedance on it, the corresponding first and second X currents I will increase. And because the impedance on the single X sensing bar 35 is lower when there are more than one contact, the corresponding first and second X currents I will further increase at this time.

Through the above-mentioned principle, the contact number determination unit 44 determines how much the change amount ΔI of the first and second X current I of the above-mentioned X sensing bar 35 is greater than the first and second X reference currents above a first critical value. In the presence of a contact, and it is determined that the change amount ΔI of the first and second X current I of the above-mentioned X sensing strip 35 is greater than the first and second X reference current and a second critical value, there is an upper one. single contact exists. Similarly, the number of contacts determination unit 44 then also determines whether the contacts P1 and P2 have the same X coordinate x and whether there are contacts with the same X coordinate x. Whether P2 has the same Y coordinate as y is similar.

Then, for the change amount ΔI of the first and second X current I that is greater than the first critical value of the first and second X reference current I, the first coordinate determination unit 46 assigns the corresponding X sensing bar 35 A Y position is the Y coordinate y of the more than one contact; the change amount ΔI for the first and second X sensing current I is greater than the first and second X reference current and the second threshold but less than the For the first critical value, the first coordinate determining unit 46 calculates an X coordinate x corresponding to the X sensing strip 35 as an x coordinate of the single touch point, wherein the X coordinate x of the single touch point is determined according to The following formula judges:

x=(ΔI2-ΔI1)/(ΔI1+ΔI2) (1).

Similarly, the first coordinate determining unit 46 calculates a Y coordinate y corresponding to the Y sensing strip 36 as a Y coordinate y of the single touch point, wherein the Y coordinate y of the single touch point is calculated according to the following formula determination:

y=(ΔI4-ΔI3)/(ΔI3+ΔI4) (2).

Since the X coordinates x of the multi-contacts P1 and P2 in FIG. 5 are the same, the corresponding change amounts ΔI of the first and second X currents I are respectively greater than the first and second reference currents and the first critical value, so more The Y coordinate y of the contacts P1 and P2 is recorded. However, if the multi-contacts are P1 and P2' at this time, then there is no change ΔI of the first and second X current I greater than the first and second reference currents and the first critical value. At this time, the multi-contacts P1 and P2' The X-coordinate values x of P2' are respectively calculated according to the above formula (1).

Next, for the situation that the above-mentioned X sensing bar 35 is judged to have more than one contact on its upper side, the second coordinate judging unit 47 utilizes the changes of the above-mentioned first and second Y currents I on the two Y sides Y1 and Y2 The quantity ΔI calculates the Y coordinate y of each of the more than one touch points, that is, the multi-touch points are P1 and P2', so as to obtain the coordinates x and y of the multi-touch points P1 and P2 located at the same Y position respectively.

If it is determined that there is more than one touch point in the X direction, and it is also determined that there is more than one touch point in the Y direction, then the Y coordinate y of the touch point processed later needs to be based on the previously obtained X coordinates. And the Y coordinates x, y determine the (x, y) coordinates of the last multi-touch. In addition, the previously determined Y-coordinates y of more than one touch point can also be reconfirmed at this time.

Finally, the position coordinate determination unit 48 pairs the X and Y coordinates x, y of each contact P1 and P2 or P2' obtained above to form a complete two-dimensional coordinate to determine the multi-contact P1 and P2 or P2 'The coordinate position (x1, y1) and (x2, y2).

FIG. 6 is a flow chart of the method for determining the position of multiple touch points on the projected capacitive touch panel of the present invention, and please cooperate with the description of FIG. 3 and FIG. 5 .

As shown in Figure 6, first a plurality of X external wires 59 and a plurality of Y external wires 59 are evenly connected to the X side X1, the multiple X sensing strips 35 on the X2 and the Y side Y1, the multiple Y2. Strip Y senses strip 36 (step 601).

Then, the two X sides X1 and X2 of the plurality of X sensing strips 35 are first provided with a sensing voltage Vs through the external wires 59 respectively, and then the two Y sides Y1 and Y2 of the Y transparent sensing layer 32 are also provided. The sensing voltage Vs is then provided in the same manner to be on at least one corresponding X sensing bar 35 of the plurality of X and Y sensing bars 35, 36 when the multi-contact P1, P2 or P2' occurs. Each form at least one X current pair group, and each form at least one Y current pair group on at least one corresponding Y sensing bar 36 (step 602), wherein the concepts of X and Y current pair groups have been described above, and now Omit it and explain it later.

In fact, each of the at least one corresponding X current pair group includes at least one X current pair, and each of the at least one X current pair has a first and a second X partial current I, and the first and the second X partial current are separated by at least one contact of the multi-contact P1 , P2 or P2 ′ on a corresponding one of the set of corresponding X sensing bars 35 . When at least one of the multi-contacts P1, P2 or P2' is more than one contact on the corresponding X sensing bar 35, the first X partial current X1 is formed on the X side X1 and the more than one contact Between one of the points closer to the X-side X1, the second X partial current I is formed between the X-side X2 and one of the more than one contacts closer to the X-side X2.

Likewise, at least one of the at least one corresponding Y current pair group includes at least one Y current pair, and each of the at least one Y current pair has a first and a second Y partial current I, and the first and The second Y partial currents I are all separated by at least one contact of the multi-contact P1 , P2 or P2 ′ on a corresponding one of the set of corresponding Y sensing bars 36 . When at least one of the multi-contacts P1, P2 or P2' is more than one contact on the corresponding Y sensing bar 36, the first Y partial current I is formed between the first Y side Y1 and the multi-contacts. Between a contact closer to the Y-side Y1, the second Y partial current I is formed between the Y-side Y2 and one of the more than one contacts closer to the Y-side Y2 .

Then, respectively sense an X current and a Y current on each of the X and Y sensing strips 35, 36 in order to respectively obtain the at least one set of X current pairs and the at least one set of Y current pairs, Respectively determine the first and second X partial currents I of each of the at least one X current pair, and the first and second Y partial currents of the first and second Y current pairs of each of the at least one Y current pair I, and respectively determine a maximum first and second X partial current I of the first and second X partial current I and a maximum first and second Y partial current I of the first and second Y partial current I current I, and the maximum first and second X and Y currents are referred to here as a first and second X and Y current I, respectively (step 603).

Then, compare the first and second X current I with a first and second X reference current respectively, and then compare the first and second Y current I with a first and second Y reference current respectively, to respectively Obtain a current variation ΔI of the first and second X and Y currents (step 604 ).

Next, determine whether there is more than one contact on the X sensing bar 35 corresponding to the first and second X current I according to whether the current change ΔI of the first and second X current I is greater than a first critical value and determine the X sensing bar 35 corresponding to the first and second X current I according to whether the change amount ΔI of the first and second X current I is less than the first critical value but greater than a second critical value There is only one single contact on the top, and judge the Y sensing bar 36 corresponding to the first and second Y current I according to whether the change amount ΔI of the first and second Y current I is greater than a first critical value Whether there is more than one contact on the contact, and judge the first and second Y currents according to whether the change amount ΔI of the first and second Y currents I is less than the first critical value but greater than a second critical value There is only one single contact on the Y sensing bar 36 corresponding to I (step 605 ).

Next, determine the Y coordinate y of the position with the more than one touch point on the corresponding X sensing strip 35, and determine the X and Y coordinates x, y of the position of the single touch point on the corresponding X sensing strip 35 (step 606).

Then, determine the X coordinate x and Y coordinate y of the single contact on the corresponding Y sensing strip 36, and according to the X and Y coordinates x, y, the single contact on the corresponding X sensing strip 35, the The Y coordinate y of more than one contact on the corresponding X sensing bar 35, and the x and y coordinates of a single contact and more than one contact on the corresponding Y sensing bar 36 are used to determine the corresponding The X and Y coordinates x, y of each contact position of more than one contact point on the X sensing strip, and the Y of the contact position of more than one contact point on the corresponding X sensing strip 35 that has been determined Coordinate y is reconfirmed (step 607).

Finally, the coordinates x and y on the X and Y axes of the determined multi-contacts P1 and P2 are paired to determine the position coordinates (x1, y1) and (x2, y2) of the multi-contacts P1 and P2 (step 608).

Among the above, the step of obtaining the X coordinate x of the single contact at an X position in step 605 is obtained by the above relational formula (1), and the step of obtaining the single contact at a Y position at step 405 The step of the Y coordinate y of Y is obtained by the above-mentioned relational formula (2).

In a different embodiment, the positions of the X and Y transparent sensing layers 32, 34 are interchanged. In a different embodiment, the Y transparent sensing layer 34 is first applied with the sensing voltage Vs, and the X transparent sensing layer 32 is then applied with the sensing voltage Vs.

By using the present invention, the positions of the multi-touch points can be completely determined on the capacitive touch panel with sensing patterns, so that this kind of touch panel can be officially used for multi-touch touch.

Of course, the present invention can also have other various embodiments, and those skilled in the art can make various corresponding changes and deformations according to the present invention without departing from the spirit and essence of the present invention. All changes and deformations should belong to the protection scope of the appended claims of the present invention.

Claims (11)

1. A device for determining the position of multiple contacts on a projected capacitive touch panel, wherein the projected capacitive touch panel comprises a transparent substrate formed in the same shape and stacked up sequentially, a Y transparent sensing layer, a transparent a dielectric layer and an X transparent sensing layer, the X transparent sensing layer has a plurality of X sensing strips arranged along an X direction, and has a first X side and a second X side in the X direction, The Y transparent sensing layer has a plurality of Y sensing strips arranged along a Y direction, and has a first Y side and a second Y side in the Y direction, and the multi-contact makes the X transparent sensing layer In contact with the Y transparent sensing layer at the multi-contact position, it is characterized in that the device includes: A plurality of X external wires and a plurality of Y external wires are respectively used to electrically connect the plurality of X and Y sensing strips along the first and second X sides and the first and second sides in a one-to-one relationship. Y side; A sensing source is used to sequentially provide an AC sensing voltage to the plurality of X sensing strips on the first X side and the second X side through the plurality of X external wires, and then sequentially pass through the plurality of X sensing strips The Y external wire provides the AC sensing voltage to the plurality of Y sensing strips on the first Y side and the second Y side, so that at least one of the plurality of X and Y sensing strips occurs when the multi-contact occurs. At least one X current pair group is formed on each group corresponding to the X sensing strips, and at least one Y current pair group is formed on at least one corresponding Y sensing strip, wherein each of the at least one corresponding X current pair group includes At least one X current pair, and each of the at least one X current pair has a first and a second X partial current, and the first and second X partial currents are corresponding to the multi-contact in the group At least one contact on a corresponding one of the X-sensing strips is separated, and when at least one of the multi-contacts is more than one contact on the corresponding X-sensing strip, the first X partial current is Formed between the first X side and one of the more than one contacts that is closer to the first X side, the second X partial current is formed between the second X side and the more than one contacts one closer to the second X side, and at least one of the at least one corresponding Y current pair group includes at least one Y current pair, and each of the at least one Y current pair has a first and a first Two Y partial currents, and the first and second Y partial currents are all separated by at least one contact of the multi-contact on a corresponding one of the corresponding Y sensing strips, and when the multi-contact When at least one of the corresponding Y sensing strips is more than one contact, the first Y partial current is formed on the first Y side and one of the more than one contacts is closer to the first Y side Between them, the second Y partial current is formed between the second Y side and one of the more than one contacts that is closer to the second Y side; A current sensing unit is used to sequentially sense an X current and a Y current on each of the X and Y sensing strips on the first and second X and Y sides respectively, so as to respectively obtain the at least A group of X current pairs and the at least one group of Y current pairs are used to determine the first and second X partial currents of each of the at least one X current pair, and the first and second partial currents of each of the at least one Y current pair. The first and second Y partial currents of the second Y current pair, and determining a maximum first and second X partial current and the first and second Y partial currents of the first and second X partial currents, respectively A maximum first and second Y partial current in the current, and the maximum first and second X and Y partial currents are respectively used as a first and second X and Y current current comparison unit for comparing the The first and second X currents are compared with a first and second X reference current, and then the first and second Y currents are respectively compared with a first and second Y reference current to obtain the first and second Y reference currents, respectively. A current change amount of the X and Y currents; A contact number determination unit is used to determine that there are more than one X sensing strips corresponding to the first and second X currents according to the current variation of the first and second X currents being greater than a first critical value. Contact exists, and according to the change amount of the first and second X current is less than the first critical value but greater than a second critical value, it is determined that only the X sensing strip corresponding to the first and second X current There is a single contact, and according to the change of the first and second Y currents greater than a first critical value, it is determined that there are more than one touches on the Y sensing strip corresponding to the first and second Y currents. point, and according to the change of the first and second Y currents less than the first critical value but greater than a second critical value, it is determined that only the Y sensing strip corresponding to the first and second Y currents has the presence of a single contact; A first coordinate determination unit, used to determine the Y coordinate y of the position that is determined to have the more than one touch point on the corresponding X sensing strip, and determine the position that is determined to be on the corresponding X sensing strip The X and Y coordinates x, y of the position of the single contact on the A second coordinate determining unit, used to determine the X coordinate x and Y coordinate y of the single contact determined to be on the corresponding Y sensing strip, and according to the determined single touch point on the corresponding X sensing strip The X and Y coordinates x, y of a single contact on the corresponding X sensing strip, the Y coordinate y of more than one contact on the corresponding X sensing strip, and the single contact and more than one touching on the corresponding Y sensing strip The x and y coordinates of the point determine the X and Y coordinates x, y of each contact position of more than one contact point on the corresponding X sensing strip, and determine the corresponding X sensing strip for the corresponding X sensing strip. Reconfirmation at the Y-coordinate Y of the contact position of a contact; and A position coordinate determination unit is used to match the x and y coordinates of the single contact and more than one contact on the corresponding X and Y sensing strips to determine the position of the multi-contact; wherein: The determination of the x-position of a single contact by the first coordinate determination unit is carried out according to the following relational formula: x＝(ΔI2-ΔI1)/(ΔI1+ΔI2), and The determination of the y position of a single contact point by the second coordinate determination unit is carried out according to the following relational formula: y=(ΔI4-ΔI3)/(ΔI3+ΔI4), Wherein ΔI1, ΔI2, ΔI3, and ΔI4 are current change amounts of the first X, the second X, the first Y, and the second Y currents, respectively. 2. The device for determining the positions of multiple contacts on a projected capacitive touch panel according to claim 1, wherein the first and second X reference currents are the first and second X currents at the multiple touch points The current before the multi-contact appears, and the first and second Y reference currents are the currents of the first and second Y currents before the multi-contact appears. 3. The device for determining the position of multiple contacts on a projected capacitive touch panel according to claim 1, wherein: I1 and I2 are the first and second X currents respectively, I3 and I4 are the first and second Y currents respectively, and ΔI1, ΔI2, ΔI3 and ΔI4 are respectively I1, I2, I3 and I4 in the multi-contact The difference between when it appeared and before it appeared. 4 . The device for determining the positions of multiple touch points on a projected capacitive touch panel according to claim 1 , wherein the positions of the X and Y transparent sensing layers are interchanged. 5. The device for determining the position of multiple contacts on a projected capacitive touch panel according to claim 1, wherein the Y transparent sensing layer is first applied with the sensing voltage, and the X transparent sensing layer is applied Then add the sensing voltage. 6. A method for determining the position of multiple contacts on a projected capacitive touch panel, wherein the projected capacitive touch panel comprises a transparent substrate, a Y transparent sensing layer, a transparent a dielectric layer and an X transparent sensing layer, the X transparent sensing layer has a plurality of X sensing strips arranged along an X direction, and has a first X side and a second X side in the X direction, The Y transparent sensing layer has a plurality of Y sensing strips arranged along a Y direction, and has a first Y side and a second Y side in the Y direction, and the multi-contact makes the X transparent sensing layer The transparent dielectric layer in contact with the Y transparent sensing layer at the multi-contact position is characterized in that the method comprises the following steps: A plurality of X external wires and a plurality of Y external wires are respectively used to electrically connect the plurality of X and Y sensing strips along the first and second X sides and the first and second sides in a one-to-one relationship. Y side; Sequentially provide an AC sensing voltage to the multiple X sensing strips on the first X side and the second X side through the multiple X external wires, and then sequentially provide the AC sensing voltage through the multiple Y external wires A voltage is applied to a plurality of Y sensing strips on the first Y side and the second Y side, so that each of the corresponding X sensing strips of at least one group of the plurality of X and Y sensing strips when the multi-contact occurs At least one X current pair is formed, and at least one Y current pair is formed on at least one corresponding Y sensing bar, wherein each of the at least one corresponding X current pair includes at least one X current pair, and the at least one corresponding X current pair includes at least one X current pair, and the Each of the at least one X current pair has a first and a second X partial current, and the first and second X partial currents are a corresponding pair of the multi-contact on the set of corresponding X sensing bars. and when at least one of the multi-contacts is more than one contact on the corresponding X sensing strip, the first X partial current is formed between the first X side and Between the one of the more than one contacts that is closer to the first X side, the second X partial current is formed between the second X side and the one of the more than one contacts that is closer to the second X Between the sides, and at least one of the at least one corresponding Y current pair group includes at least one Y current pair, and each of the at least one Y current pair has a first and a second Y partial current, and the first Both the first and second Y partial currents are separated by at least one contact of the multi-contact on a corresponding one of the set of corresponding Y-sensing bars, and when at least one of the multi-contacts is on the corresponding Y-sensing strip When there is more than one contact on the test strip, the first Y partial current is formed between the first Y side and one of the more than one contacts closer to the first Y side, the second Y a portion of the current flow is formed between the second Y side and one of the more than one contacts that is closer to the second Y side; Sequentially sensing an X current and a Y current on each of the X and Y sensing bars on the first and second x and y sides, respectively, to obtain the at least one X current pair and the at least one Y current, respectively pair, respectively determine the first and second X partial currents of each of the at least one X current pair, and the first and second Y partial currents of the first and second Y current pairs of each of the at least one Y current pair current, and determine a maximum first and second X partial current among the first and second X partial currents and a maximum first and second Y partial current among the first and second Y partial currents, respectively, and the maximum first and second X and Y partial currents are taken as a first and second X and Y current, respectively; comparing the first and second X currents with a first and second X reference currents respectively, and then comparing the first and second Y currents with a first and second Y reference currents respectively to obtain the first and a current change amount of the second X and Y currents; According to the current change of the first and second X currents being greater than a first critical value, it is determined that there are more than one contacts on the X sensing strip corresponding to the first and second X currents, and respectively according to the When the change amount of the first and second X currents is less than the first critical value but greater than a second critical value, it is determined that there is only a single contact on the X sensing strip corresponding to the first and second X currents, and According to the change of the first and second Y currents greater than a first critical value, it is determined that there are more than one contacts on the Y sensing strip corresponding to the first and second Y currents, and respectively according to the first and second Y currents. When the amount of change of the first and second Y currents is less than the first critical value but greater than a second critical value, it is determined that there is only a single contact on the Y sensing strip corresponding to the first and second Y currents; Determining the y-coordinate of the location determined to have the more than one touch point on the corresponding X-sensing strip, and determining the x and y coordinates of the location determined to be a single contact on the corresponding X-sensing strip coordinate; Determine the X coordinate x and Y coordinate y of the single contact that is determined to be on the corresponding Y sensing strip, and according to the X and Y coordinate x of the single contact that is determined to be on the corresponding X sensing strip , y, the Y coordinate y of more than one contact on the corresponding X sensing strip, and the x and y coordinates of the single contact and more than one contact on the corresponding Y sensing strip determine the Corresponding to the X and Y coordinates x, y of each contact position of more than one contact on the X sensing strip, and the Y of the determined contact position of more than one contact on the corresponding X sensing strip Coordinate y is reconfirmed; and pairing the x and y coordinates of the single contact and more than one contact on the corresponding X and Y sensing strips to determine the position of the multiple contacts; Wherein the step of determining the x and y coordinates of the contact position determined as a single contact is carried out according to the following relational formula: x=(ΔI2-ΔI1)/(ΔI1+ΔI2), and y=(ΔI4-ΔI3)/(ΔI4+ΔI3), Wherein ΔI1, ΔI2, ΔI3, and ΔI4 are current change amounts of the first X, the second X, the first Y, and the second Y currents, respectively. 7. The method for judging the positions of multiple contacts on a projected capacitive touch panel according to claim 6, wherein the first and second X partial currents are compared with a first and second X current respectively. The step of referring to the current, and then comparing the first and second Y partial currents with a first and second Y reference current, respectively, further includes the following steps: Before the multi-contact occurs, the first and second X and Y currents are respectively sensed as the first and second X and Y reference currents, respectively. 8. The method for determining the positions of multiple contacts on a projected capacitive touch panel according to claim 6, wherein I1 and I2 are respectively the first and second X currents, and I3 and I4 are respectively the first and second X currents. The first and second Y currents, and ΔI1 , ΔI2 , ΔI3 , and ΔI4 are respectively a difference between I1 , I2 , I3 , and I4 when the multi-contact appears and before it appears. 9 . The method for determining the positions of multiple touch points on a projected capacitive touch panel according to claim 6 , wherein the positions of the X and Y transparent sensing layers are swapped. the 10. The method for determining the position of multiple contacts on a projected capacitive touch panel according to claim 6, wherein the X transparent sensing layer is first applied with the sensing voltage, and the Y transparent sensing layer is applied Then add the sensing voltage. 11. The method for determining the position of multiple contacts on a projected capacitive touch panel according to claim 6, wherein the first and second X and Y reference currents are respectively on the corresponding contacts Corresponding to the first and second X and Y currents on the X and Y sensing strips when the contact is not present. the

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