TWI529571B - Touch panel for determining real coordinates of multiple touch points, touch input device, and determining method - Google Patents

Description

Touch panel, touch device and detection method for detecting true coordinates of multi-touch points

The invention relates to the field of touch, and particularly relates to a touch panel for detecting multi-touch points, a touch device using the touch panel, and a method for detecting a true coordinate of a multi-touch point.

At present, the technology of directly operating electronic devices by touching touch objects such as fingers has been widely used in daily work and life. The electronic devices generally employ a touch device to sense a touch action and generate a corresponding electrical signal for subsequent operation. The touch device is often in the form of a touch panel, a touch screen, or the like in actual production or use.

According to different touch principles, touch panels are mainly classified into resistive, capacitive, optical, electromagnetic, and acoustic waves. The working principle of the capacitive touch panel is that the touch surface of the panel is touched by the user with a conductive touch object such as a finger or a sensor pen, causing a voltage change at the position where the panel is touched. The processor detects the coordinates of the touched position according to the voltage change to achieve the purpose of the touch operation. The working principle of the optical touch panel and the acoustic touch panel are similar, and the light source or sound wave is generated by the source, and the receiving device is arranged on the wave propagation route. When a touch occurs, the touch object blocks the wave propagation, and the signal received by the receiving device generates an abnormality to detect the touch point position.

In order to cooperate with different electronic devices, the industry has developed a variety of different capacitive touch panels, and projected capacitive touch panels are one of them. As shown in FIG. 1 and FIG. 2 , a conventional projected capacitive touch pattern 1 having a grid shape includes a first electrode 2 along a first direction, a second electrode 3 along a second direction, and an insulating layer 4 and a substrate 5 . . The first electrode 2 and the second electrode 3 are mutually distributed on the substrate 5, and the intersections are separated by an insulating layer 4. In addition, a processor (not shown) is connected to the two sets of electrodes 2, 3. When a conductive touch object touches the surface of the touch panel, each set of electrodes will have a self-capacitance change, which can be detected and measured by the processor. The position of the centroid of the self-capacitance change on each set of electrodes represents the position of the touch point in each electrode direction, and the coordinate position of the touch point is calculated by the cross-matching of the centroids in the two sets of electrode directions. Therefore, the conventional detection method steps are: a) scanning the first electrode 2 and the second electrode 3 respectively; b) analyzing the centroid of the self-capacitance change of the touch point on the two electrodes; c) calculating from the centroid The coordinates of the touch point.

When at least two touch points appear on the surface of the touch panel at the same time, taking the two touch points C and D as an example, as shown in FIG. 3, the two centroids are resolved in the direction of each set of electrodes, that is, the centroid 6a in the first direction. , 6b and the centroids 7a, 7b in the second direction, the two sets of centroids are arranged to cross each other, and the four coordinate positions C (6a, 7a), C' (6a, 7b), D' (6b, 7a) are calculated. D(6b, 7b), where only two coordinates are the true coordinates C (6a, 7a), D (6b, 7b) of the two touch points, and the other two coordinates are false coordinates C' (6a, 7b), D '(6b, 7a).

Similar to the touch point detection principle of the projected capacitive touch panel, the optical touch panel and the acoustic touch panel also utilize the two-way sensing line to sense the position where the touch point is abnormal in the second direction. Heart, and then calculate the touch point coordinates by means of cross configuration. Therefore, when the number of touch points is more than two, a problem of false coordinates may also occur.

It can be seen that, regardless of the use of the conventional projected capacitive touch panel, when the optical touch panel and the acoustic touch panel are used to detect at least two touches, the false coordinates of the touched points are inevitably generated. The application of the touch panel is limited. Therefore, how to calculate the true coordinates in the detection of at least two touches and eliminate the false coordinates has become a problem to be solved in such a touch panel and its detection method.

In view of the above, it is necessary to provide a touch panel for detecting the true coordinates of the multi-touch point and a touch device using the touch panel, so that when the touch panel detects multiple touch points, the true coordinates can be accurately determined. At the same time, the false coordinates are removed.

It is also necessary to provide a method for detecting the true coordinates of a multi-touch point.

A touch panel for detecting a true coordinate of a multi-touch point includes a sensing circuit layer having a first line and a second line for detecting an original coordinate of the multi-touch point. Providing, on one side of the sensing circuit layer, a judging circuit layer for rejecting a false coordinate in the original coordinate detected by the sensing circuit layer and outputting the true coordinate, wherein the determining circuit layer has a third line .

A touch device for detecting a true coordinate of a multi-touch point includes the above-mentioned touch panel, a wire and a processor for detecting a true coordinate of the multi-touch point. The wires are electrically connected to the sensing circuit layer and the circuit layer to the processor, respectively.

A method for detecting a true coordinate of a multi-touch point includes the following steps: a) when at least two touch points are simultaneously generated on the surface of the touch panel, the processor separately scans the first line of the sensing circuit layer in the first direction And a second line located in the second direction; b) the processor parses the centroid of the self-capacitance change of the touch point in the first direction and the second direction, and calculates the original coordinate of the touch point according to the centroid; c) In step b), when at least two centroids are parsed in both the first direction and the second direction, the processor scans to determine the third line of the line layer in the third direction; d) the processor calculates the touch point at a third-party upward projection; e) the processor calculates a projection of the original coordinates in a third direction; f) the processor determines whether the distance between the projection in step d) and the projection in step e) is less than a predetermined parameter value ;g) When the judgment result is YES, the original coordinates are the true coordinates of the touch point, and the processor outputs the true coordinates.

Another method for detecting a true coordinate of a multi-touch point includes the following steps: a) when at least two touch points are simultaneously generated on the surface of the touch panel, the processor scans the first direction of the sensing circuit layer a first line and the second line in a second direction; b) the processor parses a centroid of a self-capacitance change of the touch point in the first direction and the second direction, and Calculating an original coordinate of the touch point according to the centroid; c) when only one of the centroids is resolved in the first direction or the second direction in the step b) The original coordinates are the true coordinates of the touch point, and the processor outputs the true coordinates.

The above-mentioned touch panel and detection method for detecting the true coordinates of the multi-touch point can overcome the problem that the conventional touch panel is easy to output false coordinates when detecting multi-touch, and accurately calculate the true coordinates.

The technical features and advantages of the present invention are described in more detail below in conjunction with the drawings and exemplary embodiments. It is to be understood that the elements, structures and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.

4a is a schematic cross-sectional view of a touch panel for detecting a true coordinate of a multi-touch point according to a first embodiment of the present invention. The first embodiment is a projected capacitive touch panel. The touch panel 100 includes an inductive circuit layer 110 and a judging circuit layer 130 disposed on one side of the inductive circuit layer. The sensing circuit layer 110 includes a plurality of first electrode lines 111 distributed in a first direction (the X-axis direction in FIG. 4b), a plurality of second electrode lines 112 distributed in a second direction (the Y-axis direction in FIG. 4b), and insulation. Layer 113. The plurality of first electrode lines 111 and the plurality of second electrode lines 112 are distributed on different layers and are disposed on opposite sides of the insulating layer 113. FIG. 4b is a schematic plan view of the sensing circuit layer 110. It is judged that the wiring layer 130 includes a plurality of third electrode lines 131 distributed in the third direction (the Z-axis direction in Fig. 4c). As shown in FIG. 4c, the Z direction does not coincide with the X direction and the Y direction, and the Z direction forms an angle with each of the X direction and the Y direction. The two angles can be equal or unequal. In order to insulate the sensing circuit layer 110 and the determining circuit layer 130 from each other, an insulating substrate 120 is further disposed therebetween.

The first electrode line 111, the second electrode line 112, and the third electrode line 131 are respectively connected to the processor 150 by a plurality of wires 140 to form a detecting device 10 for detecting the true coordinates of the multi-touch point, as shown in FIG.

FIG. 6a is a schematic cross-sectional view of a touch panel 200 for detecting a true coordinate of a multi-touch point according to a second embodiment of the present invention. The touch panel 200 of the second embodiment is similar to the first embodiment, and is also a projected capacitive touch panel. The touch panel 200 includes an inductive circuit layer 210 (see FIG. 6b), a judging circuit layer 230 disposed on one side of the inductive circuit layer 210, and a gap between the sensing circuit layer 210 and the judging circuit layer 230 to insulate the two. The insulating substrate 220. The difference is that in the sensing circuit layer 210, the plurality of first electrode lines 211 distributed in the first direction X and the plurality of second electrode lines 212 distributed in the second direction Y are disposed in the same layer, at the intersection of the two electrode lines A plurality of insulating sheets 213 are disposed between the first electrode line 211 and the second electrode line 212. Referring to FIG. 6b, a schematic plan view of the sensing circuit layer 210 is shown.

The pattern structure of the X and Y direction electrode lines in the sensing circuit layer may also be different. As shown in FIG. 7 , it is a schematic plan view of the sensing circuit layer 310 of the touch panel according to the third embodiment of the present invention, which is distributed in the first direction. The plurality of first electrode lines 311 of X may be composed of a plurality of first conductive units 311a and a plurality of first wires 311b, and the plurality of first conductive units 311a are separated from each other by a plurality of first wires 311b; distributed in the second direction Y The plurality of second electrode lines 312 may be composed of a plurality of second conductive units 312a and a plurality of second wires 312b, and the plurality of second conductive units 312a are separated from each other by a plurality of second wires 312b. The plurality of first electrode lines 311 and the plurality of second electrode lines 312 are separated by an insulating layer 313. Other elements and position setting manners of the touch panel in the third embodiment are the same as those in the first embodiment.

8 is a schematic plan view of a sensing circuit layer 410 of a touch panel according to a fourth embodiment of the present invention, wherein a plurality of first electrode lines 411 distributed in a first direction X may be composed of a plurality of first conductive units 411a and a plurality of first wires 411b is composed of a plurality of first conductive units 411a separated from each other by a plurality of first wires 411b; and a plurality of second electrode lines 412 distributed in the second direction Y may be composed of a plurality of second conductive units 412a and a plurality of second wires 412b The plurality of second conductive units 412a are separated from each other and connected by a plurality of second wires 412b. The plurality of first conductive units 411a and the plurality of second conductive units 412a and the plurality of first conductive lines 411b are not in contact with each other. A plurality of insulating sheets 413 are disposed between the plurality of first wires 411b and the plurality of second wires 412b. Other components and positional settings of the touch panel in the fourth embodiment are the same as those in the second embodiment.

The above conductive unit may be of any geometric shape such as a polygon, a circle or the like. On the material of choice, it is generally a transparent conductive material such as indium tin oxide (ITO) or the like. According to different design requirements, the number of the first conductive unit and the second conductive unit are respectively at least two, and the number of the first wire and the second wire are respectively at least one.

The touch panel for detecting the true coordinates of the multi-touch point may be an optical touch panel, wherein the sensing circuit layer includes a plurality of first optical lines in the first direction X and a plurality of second optical lines in the second direction Y The circuit simultaneously determines that the circuit layer includes a plurality of third optical lines located in the third direction Z. The three-direction optical circuit may be distributed on different layers of the electrode lines of the projected capacitive touch panel, or may be distributed in the same layer. When the optical lines of the three directions are distributed in the same layer, the working sequence can be controlled by the processor, and the first optical line, the second optical line and the third optical line appear sequentially on the surface of the touch panel to complete the work of different optical lines. Since the detection principle of the optical touch panel and the acoustic wave touch panel is similar, the touch panel for detecting the multi-touch can also be an acoustic wave touch panel. The structure is the same as the above optical touch panel.

The components of the touch panel for detecting multi-touch are different according to actual needs, and may be made of a transparent material or an opaque material. The electrode line is made of a conductive material, and the insulating substrate and the insulating sheet are made of an insulating material. The opaque conductive material may be copper, aluminum, gold or the like; the transparent conductive material may be indium tin oxide (ITO) or the like; the insulating material may be resin, glass or the like. For example, when the touch panel is opaque, it can be applied to a touch operation panel of a notebook computer or the like; when the touch panel is transparent, it can be applied to a surface of a light-emitting display device such as a display to be a touch operation screen.

The plurality of first lines in the touch panel for detecting the multi-touch may be parallel to each other. Similarly, the plural second lines can also be parallel to each other; the plural third lines can also be parallel to each other.

The first line and the second line of the touch panel for detecting the multi-touch include at least two lines respectively, wherein the number of electrodes is determined by the touch resolution and size of the detecting device to be applied. The higher the general resolution requirement, the smaller the pixel requirement, the more the number of electrodes; the larger the size, the more the number of electrodes.

When at least two touch points are simultaneously generated on the surface of the touch panel, the true coordinates of at least two touch points can be obtained by the detecting method shown in FIG. 9. Taking the detection of the two touch points on the projected capacitive touch panel as an example, as shown in FIG. 10, when the touch panel surface simultaneously generates two touch points A and B, after the initial step 20, step 21 is performed. The processor separately transmits the scan signal to the plurality of first electrode lines in the X direction and the plurality of second electrode lines in the Y direction on the sensing circuit layer, and scans the electrode lines in the two directions to detect the two-direction electrode lines The self-capacitance change is generated, and the self-capacitance change signal is transmitted back to the processor; in the process of scanning the two-direction electrode line, it is judged that the plurality of third electrode lines in the Z direction on the circuit layer are short-circuited and grounded or connected To the fixed output, as a mask layer, to cover the electromagnetic field interference generated when scanning the electrode lines on the sensing circuit layer, so that the scanning process is more precise. After the scanning of the sensing circuit layer is completed, the process proceeds to step 22. The processor analyzes the centroids x1, x2, and Y of the self-capacitance change of the touch points A and B in the X direction according to the self-capacitance change data obtained by scanning. The centroids y1, y2 of the capacitance change, and the original coordinates a(x1, y1), b(x2, y2), a'(x1, y2), and b'(x2, y1) are calculated according to the centroid. In the decision step 23, the processor determines whether only one centroid is resolved in one of the X direction and the Y direction. If the result of the determination is no, that is, if x1 is not equal to x2 or y1 is not equal to y2, then proceeding to step 24, the processor transmits the scan signal by the wire to determine a plurality of third electrode lines located in the Z direction on the circuit layer, and the third The electrode line scans to detect the self-capacitance change generated by the third electrode line, and transmits the self-capacitance change signal back to the processor; during the scanning of the third electrode line, the first electrode line and the second electrode line are vacant State to avoid the effects of scanning the third electrode line. After the scanning is completed, proceeding to step 25, the processor analyzes the centroids z1 and z2 of the self-capacitance changes of the touch points A and B in the Z direction according to the data of the self-capacitance change of the third electrode line obtained by scanning, and calculates The projections D1, D2 of the two touch points A, B in the Z direction, as shown in Fig. 11, the two projections D1, D2 are the true projections of the two touch points A, B. In step 26, the processor calculates the projection D1a of the original coordinates a(x1, y1), b(x2, y2), a'(x1, y2), and b'(x2, y1) in the Z direction in step 22, D1b, D1a' and D1b' are shown in FIG. Proceeding to step 27, the projections D1a, D1b of the original coordinates a(x1, y1), b(x2, y2), a'(x1, y2) and b'(x2, y1) calculated in step 26 in the Z direction are determined. Whether the distance between D1a', D1b' and the corresponding projection of the touch points A, B calculated in step 25 in the Z direction is less than a preset parameter value P. When the judgment result is YES, the coordinates corresponding to the projection calculated in step 26 are the true coordinates of the touch points A and B, and the process proceeds to step 28, and the processor outputs the true coordinates. If the result of the determination is no, the coordinates corresponding to the projections calculated in step 26 are the false coordinates of the touch points A and B, and the process proceeds to step 29, where the processor deletes the false coordinates. For example, if the distance between D1a and D1 is less than P, the coordinate a(x1, y1) corresponding to D1a is the true coordinate of touch point A; the distance between D1a' and D1 is greater than P, then the coordinate a' corresponding to D1a' (x1, y2) is the false coordinate of touch point A. In the same way, the true coordinates of the touch point B can be judged. The preset parameter value P may be defined according to different operational requirements, for example, may be defined by the pixel corresponding to the parsing; the range of the P may be determined by specific experimental data, for example, P is at least equal to one pixel.

If the result of the determination in step 23 is YES, that is, x1 is equal to x2 or y1 is equal to y2, it indicates that the processor only parses a centroid in the X direction or the Y direction in step 22, and calculates two original coordinates. Therefore, the two original coordinates are the true coordinates of touch points A and B. After step 23, proceed directly to step 28, and the processor outputs the true coordinates.

The above processor includes a scanning unit, a calculation unit, a comparison determination unit, and an output unit. Wherein, the scanning unit is configured to provide a scanning signal to each line, and simultaneously receive an electrical signal generated during the scanning process, such as the signal of the self-capacitance change; the calculating unit performs a centroid and an original coordinate for calculating the self-capacitance change; and the comparison determining unit sets the distance The value is compared with the preset parameter value, and the corresponding judgment is made; the input unit outputs the final true coordinate to the unit performing the next operation.

The true coordinates of the output of step 28 can be output to the control device, and can also be output to the display device and the like for performing subsequent related processes. The receiving end of the true coordinate and the related process for executing are not particularly limited.

The detection method can also be used to detect the surface of the touch panel in the above embodiment, and when two or more touch points are generated, the true coordinates of the touch point are detected and judged.

When the touch panel for detecting a multi-touch is an optical or acoustic touch panel, the detection method is the same as the method for detecting the projected capacitive touch panel. I will not go into details here.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

10. . . Detection device

100, 200. . . Touch panel

110, 210, 310, 410. . . Inductive circuit layer

120, 220. . . Insulating substrate

130, 230. . . Judge line layer

111, 211, 311, 411. . . First electrode line

311a, 411a. . . First conductive unit

311b, 411b. . . First wire

112, 212, 312. . . Second electrode line

312a, 412a. . . Second conductive unit

312b, 412b. . . Second wire

113, 313. . . Insulation

213, 413. . . Insulating sheet

131. . . Third electrode line

140. . . wire

150. . . processor

FIG. 1 is a schematic diagram showing the planar structure of a conventional projected capacitive touch panel.

Figure 2 is a cross-sectional view taken along line A-A of Figure 1.

FIG. 3 is a schematic diagram of a conventional two-touch touch on the surface of a projected capacitive touch panel.

4a is a schematic cross-sectional view of a touch panel of the first embodiment.

FIG. 4b is a schematic diagram showing the planar structure of the sensing circuit layer of the touch panel shown in FIG. 4a.

FIG. 4c is a schematic diagram showing the planar structure of the circuit layer of the touch panel shown in FIG. 4a.

FIG. 5 is a schematic diagram of a detecting device having the touch panel shown in FIG. 4.

6a is a schematic cross-sectional view of a touch panel of a second embodiment.

FIG. 6b is a schematic diagram showing the planar structure of the sensing circuit layer of the touch panel shown in FIG. 6a.

7 is a schematic plan view showing a planar structure of a sensing circuit layer of a touch panel of a third embodiment.

FIG. 8 is a schematic plan view showing a planar structure of a sensing circuit layer of the touch panel of the fourth embodiment.

FIG. 9 is a flow chart of a method for detecting a true coordinate of a multi-touch point according to an embodiment.

FIG. 10 is a schematic diagram when the touch panel indicates that two touch points are generated.

11 is a schematic view showing the projection of the touch point coordinates in the third direction in FIG.

10. . . Detection device

110. . . Inductive circuit layer

130. . . Judge line layer

111. . . First electrode line

112. . . Second electrode line

131. . . Third electrode line

140. . . wire

150. . . processor

Claims (22)

A touch panel for detecting a true coordinate of a multi-touch point, comprising a sensing circuit layer having a first line and a second line, for detecting an original coordinate of the multi-touch point, wherein the improvement includes: Determining a false coordinate in the original coordinate detected by the sensing circuit layer on one side of the sensing circuit layer, and outputting the determining circuit layer of the true coordinate, wherein the determining circuit layer has a third line, wherein When scanning the sensing circuit layer, the third line is connected to a fixed output terminal for shielding the scanning sensing circuit layer. The touch panel for detecting a true coordinates of a multi-touch point according to claim 1, wherein the first line, the second line, and the third line are distributed in different directions. The touch panel for detecting the true coordinates of the multi-touch point according to claim 2, wherein the first line, the second line, and the third line respectively comprise at least two lines. The touch panel for detecting the true coordinates of the multi-touch point according to claim 1, wherein the first line, the second line, and the third line are projected capacitive electrode lines. The touch panel for detecting the true coordinates of the multi-touch point according to claim 4, wherein the sensing circuit layer and the determining circuit layer are insulated from each other. The touch panel for detecting the true coordinates of the multi-touch point according to claim 4, wherein the third line forms an angle with the first line and the second line. The touch panel for detecting the true coordinates of the multi-touch point according to claim 4, wherein the first line and the second line are distributed and insulated from each other. The touch panel for detecting the true coordinates of the multi-touch point according to claim 7, wherein the sensing circuit layer further includes an insulating layer, and the first line and the second line are respectively disposed on the Both sides of the insulation layer. The touch panel for detecting a true touch of a multi-touch point according to claim 7, wherein the sensing circuit layer further comprises an insulating sheet disposed at an intersection of the first line and the second line And located between the first line and the second line. The touch panel for detecting the true coordinates of the multi-touch point according to claim 8 or 9, wherein each of the first lines includes at least two first conductive units separated from each other and at least one connected to the first a first wire of a conductive unit, each second wire comprising at least two second conductive units separated from each other and at least one second wire connected to the second conductive unit. The touch panel for detecting the true coordinates of the multi-touch point according to claim 5, wherein an insulating substrate is disposed between the sensing circuit layer and the determining circuit layer. The touch panel for detecting the true coordinates of the multi-touch point according to claim 1, wherein the sensing circuit layer includes a plurality of first lines, and the plurality of first lines are parallel to each other. Detection of multi-touch points as described in claim 1 A true coordinate touch panel, wherein the sensing circuit layer includes a plurality of second lines, and the plurality of second lines are parallel to each other. The touch panel for detecting the true coordinates of the multi-touch point according to claim 1, wherein the judging circuit layer includes a plurality of third lines, and the plurality of third lines are parallel to each other. A touch device for detecting a true coordinate of a multi-touch point, comprising: a touch panel, a wire and a processor for detecting a true coordinate of a multi-touch point according to claim 1; wherein the wires are electrically connected The sensing circuit layer and the determining circuit layer are to the processor. A method for detecting a true coordinate of a multi-touch point includes the following steps: a) when at least two touch points are simultaneously generated on the surface of the touch panel, the processor respectively scans the first line in the first direction of the sensing circuit layer and is located at the first a second line in the second direction; b) the processor parses a centroid of the self-capacitance change of the touch point in the first direction and the second direction, and calculates the Touching the original coordinates of the point; c) when at least two of the centroids are resolved in the first direction and the second direction in the step b), the processor scans to determine the location of the circuit layer a third line in the third direction, wherein when the sensing circuit layer is scanned, the third line is connected to a fixed output end for shielding the scanning sensing circuit layer; d) the processor calculates the touch Pointing up the projection of the third party; e) the processor calculates a projection of the original coordinates in the third direction; f) the processor determines the projection in the step e) and the projection in the step d) Whether the distance is less than a preset parameter value; and g) when the judgment result is YES, the original coordinate is the true coordinate of the touch point, and the processor outputs the true coordinate. The detecting method of claim 16, wherein when the step a) is performed, the third line of the determining circuit layer is in a short circuit or a grounded state. The detecting method of claim 16, wherein when the step a) is performed, the third line of the determining circuit layer is connected to a fixed output. The detecting method of claim 17 or claim 18, wherein the determining circuit layer is a mask layer. The detecting method of claim 16, wherein when the step c) is performed, the first line and the second line are in a vacant state. The detecting method of claim 16, wherein the preset parameter value is at least one pixel. The detecting method of claim 16, wherein when the determining result of the step g) is no, the original coordinate is a false coordinate of the touch point, and the processor rejects the fake coordinate.