TW201015408A - An resolution improvement method of the object detection of capacitive touch panel - Google Patents

Abstract

An resolution improvement method of the object detection of capacitive touch panel is disclosed, which is judged through a transition point of the adjacent variation values of the conducting lines, where the variation values is calculated by two conducting lines adjacent to each other, moreover, through the arithmetic method such as interpolation calculation, the present invention could raise the resolution of the touch panel.

Description

201015408 IX. Description of the Invention: [Technical Field] The present invention relates to a side method of a control panel, and relates to a touch detection method for improving the resolution of a touch panel. [Prior Art]

A capacitive touch panel is an input device that is controlled by the charging characteristics of a finger (touch). When the panel is slid or slides on the touch panel, the capacitance on the touch panel changes. By the technique of changing the capacitance, the amount of cursor movement representing the touch object can be calculated. . Because the thickness of the capacitive touch panel is thin, it can be designed in thin notebook computers, keyboards, digital players, and the like. 1 is a conventional two-dimensional capacitive touch panel 100 comprising: a panel 102, a Y-axis sensing layer 104, an insulating layer 〇6, a χ-axis sensing layer 鄕, and a bottom plate m. When the finger U2 touches the panel 102, the position touched by it will have a corresponding (4) capacitance change, that is, a sense amount is formed. The control circuit connected to the touch panel 1 转换 can convert the change of the capacitance on the touch panel into the sensing quantity, such as the 2×*, and the position and displacement can be measured by the sensing quantity. And the direction of movement. (4) Whether the touch object touches the capacitive touch panel 100 is based on the magnitude of the sensing amount, as shown in Figure 3. When the sensing amount is greater than the threshold value th, it indicates that the touch object touches the touch panel 1〇〇; 5 201015408 f When the sensing amount is less than 阙, it means that the touch object leaves the touch panel (10) or the touch panel 100 does not touch. The object exists. However, the touch panel (10) may be disturbed by a signal of a wireless device such as a mobile phone to generate noise, so that the touch panel 彳(10) misjudges the surface touch object thereon.

:, click, move or other gestures. Figure 4A shows an example of the noise generated on the touch panel. The noise is converted by the analog digital conversion _) as shown in Fig. 4B, and finally sampled to obtain the waveform of the second image. Such a waveform diagram is similar to the waveform diagram produced when two fingers touch the touch panel 1' as shown in Fig. 5. Therefore, the noise of Fig. 4A may be misjudged as two fingers touching the touch panel 1GG, causing an erroneous operation. Therefore, how to develop a fine method to prevent noise interference has become the focus of touch panel technology development. SUMMARY OF THE INVENTION In view of the above-mentioned prior art, the method for picking up touches of a capacitive touch panel is used to achieve a calculation capacity, and the purpose of position calculation can be quickly performed. Another object of the present invention is to provide a capacitive touch panel with a touch method that enhances the anti-missing force on the touch object side. By calculating the difference of the proximity sensing amount, the external interference can be heard. For the above purpose, the present invention provides a capacitive touch panel to improve the resolution of the touch and the measurement, and the system has the _ axial fresh Two-axis matrix 6 201015408 type touch panel, including the following steps · · side of the touch panel - the first scan line of the axis physics #, · domain bribe _ gauge is the amount of change in the bribe And, if the neighbor change amount has a positive or negative value conversion point, indicating that a touch object touches the spider, the money is calculated as the position of the green material.

Further, the present invention provides a method for improving the resolution of multi-touch detection by a capacitive touch panel, which is applied to a matrix type touch panel having a first axial direction and a second extraction direction. ·] 贞 _ difficult panel - the direction of each of the 2 trace physical quantities; according to the scan line physical quantity to calculate the adjacent scan of the two scan lines = and 4 the adjacent change has a number of positive and negative value transition points, indicating that there is - touch The object touches _ broken, and the reading value calculates the position of each touch point. ', 'Let the present and other purposes, ship, and excellent miscellaneous more obvious as follows, as follows, and with the accompanying drawings, a detailed description [Embodiment] 2 touch touch When you touch the touch panel, there will be phasors at the touched area of the panel, and the amount of the bucket will change. The present invention uses the physical line judgment value of each detected scan line, that is, the _ should be the difference, to determine whether there is a touch object touch panel. Shape, which is the physical quantity diagram of the circuit of the touch panel. Xox1. 7 201015408 Χ2,···Χ7 The physical quantities of the scan lines are Cx〇, Cxi, Cx2, , where 'CxO, Cx1, Cx3, Cx4, Cx5, Cx6, Cx7 #Physical quantities are capacitance mean Ce (Equiva丨Ent Capacity), and the value of Cx2 is Ce+ACx2. This example illustrates the occurrence of a touch-up condition at point X2. In normal times, when there is no sense of occurrence, the 'physical quantity per turn' is also g卩, and the f-capacity is Ce. When the induction occurs, the capacitance changes. The graph of the adjacent inductance obtained by the actual calculation is as shown in Fig. 7, which is a graph obtained by the difference in the physical quantity of the two sweeping lines according to Fig. 6. The figure shows two adjacent inductive quantities, namely: Vdi=a(Cx2_Cxi)=aVx2, VD2=A(Cx3-Cx2)=_AVx2. Observing the change in the amount of induction in Figure 7, we can find the neighboring inductance V. The value of 1 and Vd2 is changed from a positive value (Δ(10)) to a negative value (_Δνχ2). When such a positive value turns to a negative value, it can be determined that a touch is touched. In addition to the use of a positive value to a negative value to determine the presence of a touch object touch can also be determined by the size of the threshold, as explained below: 1. When the difference value of the positive value exceeds the first threshold When Th1 (Thresh〇丨d, Th), it can be judged that a touch object touches the touch panel; 2. The difference value of the negative value is lower than the nTh2, so that the touch can be touched by the touch object. Touch panel; 3_ take the simultaneous determination of the two sides, that is, when the positive difference value exceeds the first threshold Th1' and the difference value of the negative value is lower than the second reading value 8 201015408

Th ’ can be judged that a touch object touches the touch panel, and the positive threshold and the negative threshold can be different. The fourth-threshold value Th1, the second threshold value, or the second threshold value may be the same or the two may be different. The actual values of the two can be derived from actual experiments. The adjacent sensing quantity after the conversion of the figure is the enlarged value, and as long as the reference value of the reliance value is met, it can be touched as an outline control panel. In the touch judgment of the touch object, in addition to the way of the positive and negative value conversion point, or the above-mentioned threshold riding method, the village adopts the _ mode comprehensive judgment. As for the position of the touch point, a simple judgment can be made from Fig. 7, and the position of the touch point is judged by the point of the positive and negative cut. In this embodiment, it is due to V4 V. The value of 2 exceeds the threshold value TM, _Th2, respectively, so that the touch point occurs at the points of D1 and D2, that is, the touch position of the touch object is between X1 and X3, that is, χ2. On the contrary, if the touch condition of the touch object touched in Fig. 7 disappears, that is, the judgment of the positive or negative value conversion point or the threshold value, the touch panel can be separated from the touch panel. That is, within a certain period of time (9), the above-mentioned judged touched piece disappears, and it is judged that the touched object is left. The above judgment method only provides the judgment of the touch of the touch object. For the actual touch calculation, it is necessary to provide more financial resources. Hereinafter, an embodiment will be described. 201015408 Please refer to Figure 8, which is a scan line physical quantity graph where the touch point occurs between Χ2 and χ3. The physical quantity of the scan line in this embodiment is CxO, Cx1, Cx2 at X父, XI, X2" parent 7 respectively. · Cx7, where CxO, Cx1, Cx4, Cx5, Cx6' Cx7 have physical quantities of ce (Equivalent Capacity), while Cx2, 偯 are Cx2=Ce+ACx2 Cx3=Ce+ACx3, and Cx2=Cx3. This example illustrates the presence of touch sensing in the middle of χ2, χ3. In normal times, when no induction occurs, the physical quantity of each scanning line, that is, the capacitance value is Ce, and the capacitance changes when induction occurs. The actual sensed value obtained by the actual *+ calculation is as shown in Fig. 9, which is the _ shape obtained from the difference of the physical quantities of the two scanning lines in Fig. 8. The figure shows two adjacent inductive quantities, namely: Vdi=a(Cx2_Cxi)=aVxi, VD2=A(Cx3-Cx2)=0, VD3=A(Cx4-Cx3)=-AVx3=-AVx1, where

Ox3=Cx2 ° Observing the change in the amount of inductance in Fig. 9, it can be found that the value of the adjacent inductances ^ and v is converted from a positive value (Δνχ1) to a negative value ΔVxhAvw). When such a positive value turns to a negative value, it can be judged that a touch is touched. In addition to the use of a positive value to a negative value to determine the presence of a touch object touch can also pass the _ size to make sensitive, the following side illustrates: 1_ when the positive value of the difference exceeds the first threshold value (10) Twisting d, D (1) can be judged as a touch object touches the touch panel; 2. The difference value of the negative value is lower than the second threshold value, and it can be judged that there is a touch of 201015408 The object touches the touch panel; 3_ takes two bad _ _ fixed, the foot, the positive value of the difference exceeds the threshold value Th1 'and the difference value of the negative value is lower than the second • value · Th ' It is determined that a touch object touches the touch panel, wherein the positive threshold value and the negative threshold value may be different. 4. The above is followed by Th1, and the second is followed by the absolute value of it.

The two are the same, or the two are different. The actual values of the two can be derived from actual experiments. The amount of the shouting after the conversion of Fig. 9 is the enlarged value. As long as the threshold value judgment criterion is met, it can be judged that the touch object touches the touch panel. In the touch judgment of the touch object, in addition to the way of the positive or negative value conversion point, or the above-mentioned threshold value touch mode, the _ mode comprehensive judgment can also be adopted. The point of touch is carried out by Figure 9 (4), and the judgment is as follows:

In the present embodiment, since the values of ^ and ^ exceed the threshold values Th1, -Th2, respectively, the touch point xt can be obtained at the point of (1) and the cathode, that is, the touch object The touch position occurs between χ2 and χ3, that is, Χ2·5. In the present embodiment, the touch point sensing amount is Χ2 and Χ3, and the physical quantity values are Cx2, Cx3, and y '

Cx2-Cx3. This situation / occurs at the touch point Xt just in the middle of X2 and X3. In fact, the probability of hitting Xt just touching the point on the axis is low; the general touch point is mostly between the point and the point. Please refer to FIG. 1G, which is an embodiment in which the touch point Xt of the touch panel 11 201015408 falls between Χ2 and X3. The physical quantity of the scan line of the present embodiment is at XO, X1, Χ2, ... Χ7, respectively, CxO, Cx1, Cx2, ·_·〇χ7, wherein the physical quantities of CxO, Cx1, Cx4, Cx5, Cx6, Cx7 Both are Ce (Equivalent Capacity), and the values of Cx2 and Cx3 are Cx2=Ce+ACx2, Cx3=Ce+ACx3, and Cx2>Cx3, respectively. This example illustrates the presence of touch sensing in the middle of X2, X3. In normal times, when no sense occurs, the physical quantity of each point, that is, the capacitance value is Ce, and the capacitance changes when the induction occurs. The graph of the adjacent inductance obtained by the actual calculation is as shown in Fig. 11, which is a graph obtained by the difference in the physical quantities of the two scanning lines according to Fig. 10. The figure shows two adjacent inductive quantities, namely: Vdi=a(CX2_cxi)=aVx1, V〇2=A(Cx3-Cx2)= -AVx2, Vd3=A(Cx4-Cx3)=-AVx3 ° 11 The change in the amount of induction can be found, the value of the adjacent inductances VD1 and Vd3, from the positive value (△_ to negative oblique when there is such a positive value to a negative value, it can be determined that there is a touch In the same way, in addition to the use of a positive value to a negative value to determine the presence of a touch object, the thief can also be thieves. When the first threshold value Th1 (Thresh.丨d, Th) is exceeded, it can be determined that a touch object touches the touch panel; 2. The difference value of the negative value is lower than the second. There is a touch object touching the touch panel; 12 201015408 3_ take two classes __ fixed, the value of the difference between the positive and positive values exceeds the threshold value Th1' and the difference between the negative values is lower than the second threshold -Th, it can be judged that a touch object touches the touch panel, wherein the positive threshold value and the negative threshold value can be different. "The above-mentioned threshold value ΤΜ, the second threshold value. The absolute value can be Both the same 'or both Different. The actual values of the two can be obtained by actual experiments. The adjacent inductive quantity after the transformation in Fig. 11 is the amplified value, as long as the threshold value of the above-mentioned threshold is met, the touch panel can be touched. The touch judgment of the touch object, in addition to the way of the positive and negative value conversion point, or the above-mentioned threshold value touch mode, can also be comprehensively judged by two ways. The touched point is judged by the 11th figure. The judgment mode is: a point at which the positive and negative values are converted. In the present embodiment, since the values of VD1 and VD2 exceed the threshold values Th1, -Th2, respectively, the points at D1 and D2 can be obtained as the touch point xt ', that is, The touch position of the touch object occurs between Χ2 and Χ3. Since ΔVx1?^Vx2', this touch does not occur at the position of χ25, and must be calculated by another method. The judgment point between Χ2 and Χ3, the present invention uses the internal difference method for calculation, which can greatly improve the resolution and achieve an accurate judgment of the touch position. Please refer to Fig. 12, which is a schematic diagram of the internal difference method of the present invention. , where 汾1 represents the first The position of the touch point, Xt2 represents the bit of the second touch point 13 201015408, Xd1 represents the distance between Xt1 and Di, Xd2 represents the distance between xd and Di; the adjacent inductance of Di is the proximity of AVx1 'Di+1 The difference between the amount is AVX2, and the difference of the adjacent inductance of Dj+2 is -AVxl. Among them, ΔVx2=2/3*ZWx1. Using the internal difference method, the approximate position of Xt1 and Xt2 can be calculated, as follows:

Xt1=Xi+Xd 1+0.5;

Xt2=Xi+Xd2+0.5;

Xd1=AVx1/(AVx1+AVx2)*1; Remarks: D Bu Di+1 Xd2=AVx1/(^Vx1+AVx2)*2; Remarks: D Bu Di+2 Calculated result, available:

Xt1=Xi+〇.6+〇_5=X(i+1_1)

Xt2=Xi+1+〇.5=X(i+1.5) Through the above internal difference method, the position of Xt can be calculated from the values of ΔVM and AVX2. By the calculation of the internal difference method, the accuracy of the calculation of the touch point position can be greatly improved and the overall resolution can be improved. Using the same judgment method, it is possible to judge multiple touch points on the same axis. Further, from the above method, the same conclusion can be obtained regardless of the forward amount of induction or the amount of induction in the negative direction. In the above embodiment, the Y-axis is fixed, and the touch point sensing amount on the X-axis is scanned to determine the touch point; in addition, the present invention can also be applied to the X-axis fixed, and detecting the Y-axis touch point sensing. The amount is used to determine the touch point. The method is as described above, and 201015408 will not be described again. In fact, the internal difference method proposed by the present invention is one of the mathematical approximation methods, and there are many similar approximation methods. The above method is the most (four) achievable calculation method. Other mathematical operations can be used, such as the binary approximation method, the difference method, etc., to achieve the purpose of improving the resolution of the adjacent inductance calculation method of the present invention. That is, the present invention can employ different mathematical operations to improve the physical touch difference between the two scan lines to achieve accurate touch point calculation. Although the preferred embodiments of the present invention are disclosed above, it is not intended to limit the invention, and it is possible to make some modifications and refinements without departing from the spirit and scope of the present invention. The patent protection scope of the present invention is defined by the scope of the patent application attached to the specification. [Simple diagram of the figure] Figure 1 is a conventional two-dimensional capacitive touch panel; Figure 2 is a relationship between the amount of sensing and position on the touch panel of Figure 1; Figure 3 shows the touch of two fingers. The amount of sensing detected after the touch panel; Figure 4A shows the waveform of a noise; Figure 4B shows the amount of noise obtained by the analog-to-digital conversion of the noise in Figure 4A; Figure 4 is a waveform diagram after sampling; Figure 5 is a waveform diagram detected when two fingers touch the touch panel; Figure 6 is a physical quantity diagram of the circuit of the touch panel; 15 201015408 =7 ® #' is the figure of the figure 6 of the thief's 6th product. The figure 8 is the physical quantity figure presented by the touch ©_ circuit; the 9th figure is the difference of the physical quantity of the scanning according to the 8th figure. The figure obtained by the value; the first figure is the physical quantity figure presented by the circuit of the touch panel; the 11th figure is the figure obtained by the physical quantity difference of the two lines of the second paste; and the 12th figure is A schematic diagram of the internal difference method of the present invention. [Main component symbol description] 1〇〇Touch panel 102 panel 104 Y-axis sensing layer 106 insulating layer 108 X-axis sensing layer 110 bottom plate 112 finger Cx2 X2 physical quantity Cx3 X3 physical quantity Cx5 X5 physical quantity Ce capacitance mean value 201015408

△Cx2 X2 induction △Cx5 X5 induction DO X1 minus XO neighboring inductance D1 X2 minus X1 neighboring inductance D2 X3 minus X2 neighboring inductance D3 X4 minus X3 neighboring inductance D4 X5 Subtract X4 neighboring inductance D5 X6 minus X5 neighboring inductance D6 X7 minus X6 neighboring inductance Di Xi+1 minus Xi neighboring inductance Th1 First threshold Th2 Second threshold XO X axis 0 scanning lines X1 X axis 1st scanning line X2 X axis 2nd scanning line X3 X axis 3rd scanning line X4 X axis 4th scanning line X5 X axis 5th scanning line X6 X axis 6th Scanning line X7 X-axis 7th scanning line Xd1 Distance between Xt1 and Di 17 201015408

Xd2 Distance between Xt2 and Di Xt Touch point Xt1 Touch point Xt2 Touch point e

18

Claims (1)

201015408 X. Patent application scope: 1. A method for improving the touch _ resolution of a capacitive touch panel, which is applied to a matrix having a first axial direction and a second axial direction, including the following steps, and debt testing The physical quantity of each of the first axes of the touch panel; selecting two scan lines according to the physical quantity of the scan to calculate the difference between the adjacent values, and If the neighbor change has a positive or negative value transition, the adjacent change amount exceeds the value, and the value transition and the adjacent change threshold exceeds, one of the three is one of the Danjia, indicating that a touch object touches the touch panel' and the value is Green to count _ Gu location. 2. The method of claim 1, wherein the two scanning lines are selected as follows:; picking two 'by: ton, numb X_, X2/X1, X3/X2, ... and so on ; 丨丨 _ interval scanning 蝮田裉 successive comparison, for example, X2/X0 X4/X2, X6/X4, ... and so on; 3. If the method of claim 2 is applied, the neighbor change is calculated by the power-up method, and the positive-negative conversion is converted from read to negative. 4. For example, in the second paragraph of the patent application scope, the neighbor change amount is the power drop method and the positive and negative value conversion points are converted from negative to positive values. 5. For example, the large & ^ method of the second paragraph of the patent application, wherein the first axis and the second axis are respectively the X axis, the Y axis, the γ red v god π Xingdi axis, the X axis ' one of them. 6. For the method of applying the patent scope 3 or 4 e κ A 5, wherein the positive and negative values are changed to 201015408, and the threshold value is exceeded, and one of the touches touches the judgment condition to stop the time, and then the confirmation is confirmed. The touch is off the door to the preset threshold, that is, the touch is confirmed to be touched. The branch, wherein the affixing handle is the adjacent change, ,; -_ ’ confirms that the touch is touched. 9_ The method of claim 2, wherein a positive value of the threshold value is greater than a first threshold value, and a negative value is less than a value ‘the contact is confirmed to be touched.禾一阅^如" is the green of the ninth item, and the absolute value of 愧-_ is equal to, less than 'the value greater than the second value, the value touches the touch object. 卩 Confirm 11· The method of claim 1 or 2, wherein the numerical method is one of an internal difference method, a binary approximation method, a difference method, etc. 12_- capacitive touch panel improves multi-touch The method of the resolution is used for the matrix type touch panel having the first axial direction and the second axial direction, and includes the following steps: α detecting the physical quantity of each scan line of the first axial direction of the touch panel; The physical quantity of the line selects two scan lines for the difference value to calculate the change and quantity; and if the adjacent change quantity has multiple positive and negative value transitions, the adjacent change threshold exceeds, 20 201015408 positive and negative value conversion and the adjacent change threshold exceeds, three Among them, it means that there are multiple touches touching the panel, and the position of each touch point is calculated by numerical calculation method. 13_ For example, the method of applying the patent item 12, wherein the two scanning lines The selection system is one of the following; Successive comparisons, such as χι/χ〇χ2/χι Χ3/Χ2, ... and so on; 丨丨 interval scan lines, successive comparisons, for example, χ2/χ〇, Χ4/Χ2, Χ6/Χ4,... and so on ;丨|丨·A scanning line is fixed, and other scanning lines are compared with it. 14·If the method of patent application 帛13 is applied, the adjacent variation is calculated by the method of rising curtain, and the positive and negative conversion is positive The value is converted to a negative value. 15. The method of claim 13, wherein the adjacent change mode is calculated, and the positive and negative value conversion points are converted from a negative value to a positive value / 16 · If the patent application scope is 13 items The method, wherein the first axial direction and the second axial direction are respectively an X axis, a Y axis, a Y axis, and an X axis, 17. One of the methods of claim 14 or 15 or 16, Wherein the positive and negative value conversion, it is difficult to exceed the condition of the touch of the touch of the towel, and after the second preset time is stopped, the touch object is confirmed to be left. 18_If the method of claim 13 is applied, wherein If the value exceeds the positive value of the change, the value is greater than the -th-threshold value, that is, the touch is confirmed. X 19 The method of claim 13, wherein the value exceeds the negative value of the change is less than - the second threshold, that is, the touch is confirmed to be touched. 21 201015408 20_such as the scope of patent application In the 13-item method, the positive value of the change is greater than - the first value and the value of the transcendence is the neighbor value, that is, the negative touch is less than - the second valve 21. For example, claim 20 In the method, the method is equal to, less than, greater than the absolute value of the first value of the first threshold. The absolute value of the inter-value is 'there is the confirmation ❹ Ο 22. If the application is in the 12th or the Method, the single-touch point 1 (4) breaks each touch, and the formula 'that is, 'the judgment of each point can be connected to the next two modes. The positive value is greater than the threshold value, that is, the touch is confirmed. Touching the touch object; the negative value of the _ amount is less than a second threshold value, that is, the touch object is confirmed to be touched; the positive value of the adjacent change amount is greater than a first threshold value and the negative value is less than one The second threshold is to confirm that the touch is touched. The method of claim 22, wherein the absolute value of the first threshold is equal to, less than, greater than the absolute value of the second threshold, one of which. The method of claim 12, wherein the numerical calculation method is one of an internal difference method, a binary approximation method, and a difference method. twenty two