TWI530853B - Surface capacitive touch panel and touch coordinate position determination method - Google Patents

Description

Surface capacitive touch panel and touch coordinate position determination method

The present invention relates to a touch panel, and more particularly to a surface touch panel capable of achieving multi-touch.

In the prior art, the capacitive touch panel can be classified into a surface capacitive touch panel or a projected capacitive touch panel.

The conventional surface capacitive touch panel generates an induced current due to a change in capacitance caused by capacitive coupling when the user's finger contacts the touch panel, and the induced current flows out from the electrodes disposed on the four corners of the touch panel. Then, the current intensity difference between the four corners is compared by a controller, and then the touch position coordinates are calculated. However, due to structural limitations, the conventional surface touch panel can only perform single-point touch, and cannot distinguish two or more touch positions at the same time, so that the range of the conventional surface touch panel can be applied. There are limitations.

The projected capacitive touch panel utilizes a matrix of staggered arrays formed by multiple ITO layers to achieve multi-touch performance. However, the projected capacitive touch panel requires a multi-layer structure for achieving multi-touch, and thus has a higher manufacturing cost than the surface capacitive touch panel.

One object of the present invention is to provide a surface capacitive touch panel that can be used in applications where multi-touch is required.

Another object of the present invention is to provide a method for determining a touch position coordinate, so that the surface capacitive touch panel can achieve multi-touch effect.

To achieve the above and other objects, the present invention provides a surface capacitive touch panel comprising a panel body, four electrodes, a power supply module, a grounding measurement module, and an arithmetic control. System module. The electrodes are respectively disposed on four sides of the panel body, and the electrodes respectively have a first end portion and a second end portion; the power supply module is coupled to the electrodes in response to a control signal. The power supply module is connected to the first end of the electrode to be tested to provide a power source to the electrode to be tested; the grounding measurement is performed. The module is grounded and corresponds to the control signal, and the electrode to be tested is also selected in the electrodes, so that the grounding measurement module is connected to the second end of the electrode to be tested to form a ground loop to measure Flowing through the current to be tested of the electrode to be tested and outputting a current value to be measured; and the operation control module is connected to the power supply module and the grounding measurement module to generate the control signal, and selecting each electrode by the round robin The end portion is used as the first end portion to receive the current value to be measured measured by the ground measurement module from each of the electrodes, and then calculate the touch coordinate position in each round cycle.

In an embodiment, the power supply module includes a power supply unit and a first switching unit. The power supply unit generates the power source; and the first switching unit is connected to the power supply unit and the first end of the electrode to be tested, and the first switching unit is connected to the power supply unit And between the electrodes to be tested.

In one embodiment, the grounding measurement module includes a second switching unit, a grounding unit, and a measuring unit. The second switching unit is connected to the second end of the electrode to be tested; the grounding unit has a measuring end portion and a grounding end portion, and the measuring end portion and the second switching portion The unit is connected; and the measuring unit is connected to the measuring end to measure the current value to be measured.

In an embodiment, the grounding measurement module includes: a second switching unit, a grounding unit, and a measuring unit. The second switching unit is connected to the second end of the electrode to be tested; the grounding unit has two ends, one of the ends is connected to the second switching unit, and the like The other end of the end is grounded; and the measuring unit is connected to a measuring point of the electrode to be tested to measure the current value to be measured.

To achieve the above and other objects, the present invention provides a surface capacitive touch panel comprising a panel body, four electrodes, a first power supply module, a first ground measurement module, and a second power supply. The module, a second grounding measurement module and an arithmetic control module. The electrodes are respectively disposed on four sides of the panel body, and the electrodes respectively have a first end portion and a second end portion; the first power supply module is coupled to the electrodes in response to a control signal One of the first power supply modules is connected to the first end of the first electrode to be tested to provide a first power supply to the first In the electrode to be tested; the first grounding measurement module is grounded and corresponds to the control signal, and the first electrode to be tested is also selected, so that the first grounding measurement module and the first to be tested The second end of the electrode is connected to form a ground loop to measure the first current to be measured flowing through the first electrode to be tested and output a first current value to be tested; the second power supply module responds a control signal is connected to the electrode different from the first electrode to be tested as a second electrode to be tested, and the second power supply module is connected to the first end of the second electrode to be tested to provide a a second power source to the second electrode to be tested; the second grounding amount measuring mode Grounding and returning to the control signal, and selecting the second electrode to be tested in the same electrode, connecting the second grounding measurement module to the second end of the second electrode to be tested to form a ground a loop to measure a second current to be measured flowing through the second electrode to be tested and output a second current to be measured; and the operation control module is connected to the first power supply module, the second power supply module, The first ground measurement module and the second ground measurement module generate the control signal, and select one end of each electrode as the first end to receive the first ground measurement module. And the second grounding measurement module respectively measures the first current value to be measured and the second current value to be measured on each of the electrodes, thereby calculating a touch coordinate position in each round cycle.

In an embodiment, the first power supply module includes: a power supply unit and a first switching unit. The power supply unit generates the power source; and the first switching unit is connected to the power supply unit and the first end of the first electrode to be tested, and the first switching unit is connected to the power source Between the supply unit and the first electrode to be tested.

In an embodiment, the first grounding measurement module includes: a second switching unit, a grounding unit, and a measuring unit. The second switching unit is connected to the second end of the first electrode to be tested; the grounding unit has a measuring end and a grounding end, and the measuring end is connected to the first The two switching units are connected; and the measuring unit is connected to the measuring end to measure the first current value to be tested.

In an embodiment, the first grounding measurement module includes: a second switching unit, a grounding unit, and a measuring unit. The second switching unit is connected to the second end of the electrode to be tested; the grounding unit has two ends, one of the ends is connected to the second switching unit, the ends The other part is grounded; and the measuring unit is connected to a measuring point of the electrode to be tested to measure the first current value to be tested.

In an embodiment, the second power supply module includes: a power supply unit and a first switching unit. The power supply unit generates the power source; and the first switching unit is connected to the first end of the power supply unit and the second electrode to be tested, and the first switching unit is connected to the power source Between the supply unit and the second electrode to be tested.

In an embodiment, the second grounding measurement module includes: a second switching unit, a grounding unit, and a measuring unit. The second switching unit is connected to the second end of the second electrode to be tested; the grounding unit has a measuring end and a grounding end, and the measuring end is connected to the first The two switching units are connected; and the measuring unit is connected to the measuring end to measure the second current value to be tested.

In an embodiment, the second grounding measurement module includes: a second switching unit, a grounding unit, and a measuring unit. The second switching unit is connected to the second end of the electrode to be tested; the grounding unit has two ends, one of the ends is connected to the second switching unit, the ends The other part is grounded; and the measuring unit is connected to one measuring point of the second electrode to be tested to measure the first current value to be tested.

In order to achieve the above and other objects, the present invention provides a method for determining the position of a touch coordinate, which is used for determining a coordinate position of a touch surface on a surface capacitive touch panel according to any one of the above, and determining the position of the touch coordinate The method comprises: S10: a current measurement step to be measured, measuring a current to be measured flowing through the electrodes; S12: a total current measurement step to be measured, comparing the sum of the waiting currents with a predetermined one of the total current standard values When the sum of the waiting currents is greater than the total current standard value, the process proceeds to S14; S14: the central coordinate position confirmation step, and the center coordinate position between the plurality of touch coordinate positions is calculated by the waiting current measurement; S16: The point touch coordinate position confirmation step is performed by fitting the center coordinate position correction to obtain the touch coordinate positions.

In an embodiment, when the sum of the standby currents is not greater than the total current standard value, the process proceeds to S24: calculating a touch coordinate position by the waiting current measurement.

Therefore, the surface capacitive touch panel of the present invention can be judged by the intensity of the induced currents by the eight induced currents generated around the surface of the capacitive touch panel by the finger touching the panel body. The coordinate position of the finger contacting the surface capacitive touch panel can accurately determine the coordinate position of the touch point whether it is applied to single touch or multi-touch, so that the surface capacitive type of the present invention The touch panel has a wider range of applications than the conventional surface capacitive touch panel.

1,1',1"‧‧‧ surface capacitive touch panel

10‧‧‧ Panel body

20, 21‧‧‧Power supply module

201‧‧‧Power supply unit

202‧‧‧First switching unit

30, 31‧‧‧ Grounding measurement module

301‧‧‧Second switching unit

302‧‧‧ Grounding unit

303‧‧‧Measurement unit

304‧‧‧measuring end

305‧‧‧ Grounding end

40‧‧‧Operation Control Module

50, 51, 52‧‧‧ touch location

P‧‧‧ central location

E1‧‧‧first electrode

E2‧‧‧second electrode

E3‧‧‧ third electrode

E4‧‧‧fourth electrode

E11, E12, E21, E22‧‧‧ end

E31, E32, E41, E42‧‧‧ end

E43‧‧‧Measurement point

I _E11 , I _E12 , I _E21 , I _E22 ‧‧‧ Current to be measured

I _E31 , I _E32 , I _E41 , I _E42 ‧‧‧ Current to be measured

S10, S12, S14, S16, S24‧‧ steps

1 is a schematic view showing a first embodiment of a surface capacitive touch panel 1 of the present invention.

2 is a schematic view showing a second embodiment of the surface capacitive touch panel 1 of the present invention.

Fig. 3 is a view showing an embodiment of the surface capacitive touch panel 1' of the present invention.

Figure 4 is a schematic diagram of an embodiment of measuring the current to be measured by the measuring unit of the present invention.

Figure 5 is a flow chart of the method for judging the position of the touch coordinates of the present invention.

In order to fully understand the object, features and advantages of the present invention, the present invention will be described in detail by the following specific embodiments and the accompanying drawings, which are illustrated as follows: A schematic view of a first embodiment of a surface capacitive touch panel 1 of the invention. The surface capacitive touch panel 1 includes a panel body 10, a first electrode E1, a second electrode E2, a third electrode E3, a fourth electrode E4, a power supply module 20, and a grounding measurement module. Group 30 and an arithmetic control module 40.

The panel body 10 is an area on the surface of the capacitive touch panel 1 for a touch operation of a user (not shown), the first electrode E1, the second electrode E2, the third electrode E3, and The fourth electrode E4 is disposed around the panel body 10. The first electrode E1 has two end portions E11 and E12. The second electrode E2 has two end portions E21 and E22. The third electrode E3 has two end portions E31. E32 and the fourth electrode E4 have two end portions E41 and E42. The surface capacitive touch panel 1 provides a uniform electric field on the panel body 10. When the user touches the panel body 10 with a finger or using a stylus, a capacitive charging effect is generated. The first electrode E1, the first electrode E1 The second electrode E2, the third electrode E3, and the fourth electrode E4 generate a capacitance change. When the electrode generates a capacitance change, the operation control module 40 generates a control signal to the power control module 20, and the power supply module 20 provides a power supply to one of the electrodes to respond to the control signal. In this embodiment, the end portions E11, E12, E21, E22, E31, E32, E41, and E42 are all switchedly connected to the power supply module 20. The grounding measurement module 30 is configured to measure currents passing through the first electrode E1, the second electrode E2, the third electrode E3, and the fourth electrode E4.

The operation control module 40 is connected to the power supply module 20 and the ground measurement module 30. The operation control module 40 generates the control signal, and the power supply module 20 and the ground amount are switched by the control signal. The test module 30 is connected to the electrode to be measured to form a via. The operation control module 40 uses one of the ends E11, E12, E21, E22, E31, E32, E41, E42 of each of the electrodes E1, E2, E3, E4 by the control signal in a round robin manner. For the power supply module 20 to input the end of the power supply And selecting the corresponding end portion as the end portion for connecting the grounding measurement module 30, and performing round robin in this manner, so that the operation control module 40 receives the grounding measurement module 30 from each of the electrodes The measured current values measured on E1, E2, E3, and E4 (each electrode has two currents to be measured in two directions, and a total of eight current values to be measured), and then the touch coordinates of each round cycle are calculated. position. The round robin mode of the arithmetic control module 40 will be further described below.

The operation control module 40 can cyclically control the power supply module 20 and the ground measurement module 30 to be connected to one of the electrodes E1, E2, E3, and E4, and obtain the flow through each of the electrodes. The second current value is exemplified for measuring the current flowing through the first electrode E1. The first electrode E1 can be divided into a current I _E11 flowing from the end _E11 and The end E12 flows into a current I _E12 . First, when the current I _E11 is to be measured, the power supply module 20 is operated to be connected to the end E11 under the control signal control generated by the operation control module 40, and the ground measurement module is connected. 30 is connected to the end portion E12 to form a conductive path for the current I _{E11 to} flow out of the power supply module 20 and then enter the ground measurement module 30 after passing through the first electrode E1. Therefore, the grounding measurement module 30 can measure the current I _E11 flowing through the first electrode E1; and when the current I _E12 is to be measured, the power supply module 20 is in the operation control module. The control signal generated by 40 can be operated to be connected to the end portion E12, and the grounding measurement module 30 is connected to the end portion E11 to form a conductive path for the The current I _E12 flows out of the power supply module 20 and then passes through the first electrode E1 and enters the ground measurement module 30. The ground measurement module 30 can be measured and obtained through the first electrode. Current I _{E12 of} E1. In the same manner, the operation control module 40 can also obtain the currents I _E21 , I _E22 passing through the second electrode E2 , the currents I _E31 , I _E32 passing through the third electrode E3 , and the fourth electrode E4 . current I _E41, I _E42, a total of eight current.

In the embodiment, the power supply module 20 includes a power supply unit 201 and a first switching unit 202. The power supply unit 201 is configured to provide the power to the electrodes. In this embodiment, the power supply unit 201 is an AC power supply unit to provide an AC power supply. The first The switching unit 202 is selectively controllably connected to one of the end portions E11, E12, E21, E22, E31, E32, E41, E42 according to the current to be measured to provide the power supply. To the end of the selected electrode.

In this embodiment, the grounding measurement module 30 includes a second switching unit 301, a grounding unit 302, and a measuring unit 303. The second switching unit 301 can also be programmed to selectively switch the connected electrodes, and correspondingly connected to the other end of the electrode according to the end of the electrode to which the first switching unit 202 is connected. A conductive path is formed. The grounding unit 302 has a measuring end portion 304 and a grounding end portion 305. The measuring end portion 304 is connected to the second switching unit 301, and the grounding end portion 305 is used for grounding. The measuring unit 303 is connected to the measuring end 304 to measure the current value of the current transmitted through the conductive path. It can be understood by those skilled in the art that the grounding unit 302 can be a resistor, a capacitor, a solid ground circuit composed of a single or a plurality of components, and any physical ground loop can be formed on the ground. The circuit configuration is the scope of protection of the present invention.

The eight currents to be measured flowing through the electrodes are obtained through the above (the current flow direction can be divided into two types on each electrode, so two currents to be measured on each electrode must be measured), when the user When a finger or a touch pen is used to contact the touch position 50 of the panel body 10, the coordinate value (X, Y) of the touch position 50 can be obtained by taking the waiting current value into the following two formulas: X= [(I _E41 +I _E42 )-(I _E21 +I _E22 )]/(I _E41 +I _E42 +I _E21 +I _E22 );Y=[(I _E11 +I _E12 )-(I _E31 +I _E32 ) ] / (I _E11 + I _E12 + I _E31 + I _E32 ).

Please refer to FIG. 2 , which is a schematic view of a second embodiment of the surface capacitive touch panel 1 of the present invention. When there are two touch positions 51, 52 on the panel body 10, the total sum of the currents I _E11 , I _E12 , I _E21 , I _E22 , I _E31 , I _E32 , I _E41 , I _E42 is greater than only When there is a current sum of the touch positions, the surface capacitive touch panel 1 determines that the multi-finger touch is at this time. The current sum of the touch currents can be used as a total current standard value for determining whether the multi-touch is used. However, the present invention is not limited thereto, and the total current standard value may also be A preset value.

After obtaining the currents I _E11 , I _E12 , I _E21 , I _E22 , I _E31 , I _E32 , I _E41 , I _E42 , the coordinate addresses obtained according to the second formula will be the touch positions 51 , 52 . The coordinate position (X ₀ , Y ₀ ) of one of the center positions P, and the coordinate positions (X ₁ , Y ₁ ) and (X ₂ , Y ₂ ) of the touch positions 51, 52 are further by the following formula To calculate (X ₁ , Y ₁ ) and (X ₂ , Y ₂ ): ΔX = fx [X ₀ , Y ₀ , (I _E41 + I _E42 + I _E21 + I _E22 ) / I _T ]; ΔY = Fy[X ₀ , Y ₀ , (I _E11 +I _E12 +I _E31 +I _E32 )/I _T ]; X ₁ =X ₀ -ΔX/2; X ₂ =X ₀ +ΔX/2;Y ₁ =Y _{0 -} ΔY/2; Y ₂ = Y ₀ + ΔY/2.

Wherein, I _T =I _E11 +I _E12 +I _E21 +I _E22 +I _E31 +I _E32 +I _E41 +I _E42 , ΔX=X ₁ -X ₂ , ΔY=Y ₁ -Y ₂ , and the fx and fy It is produced by the correction fitting, and those skilled in the art to which the present invention pertains can understand that the fx and fy generated by the correction fitting will be made of the material of each panel, the size of the panel, and the shape of the panel. And it is different.

In summary, the surface capacitive touch panel of the present invention can obtain the coordinate position of a single point or multi-touch on the panel body by measuring the eight currents to be measured.

Please refer to FIG. 3, which is a schematic diagram of the surface capacitive touch panel 1' of the present invention. Compared with the surface capacitive touch panel 1 , the surface capacitive touch panel 1 ′ has two power supply modules 20 , 21 and two ground measurement modules 30 , 31 , and the power supply modules The grounding measurement modules are connected to the arithmetic control module 40. In this embodiment, the power supply module 20 is connected to the end portions E11, E12, E41, and E42; the power supply module 21 is connected to the end portions E21, E22, E31, and E32; The grounding measurement module 30 is connected to the end portions E31, E32, E41, and E42. The grounding measurement module 31 is connected to the end portions E11, E12, E21, and E22. Therefore, the surface capacitive touch panel 1 ′ can measure two currents to be measured simultaneously in a single time, for example, when the power supply module 20 is connected to the end E42 and the ground measurement The module 30 is connected to the end E41 to measure the current I _{E42 to} be tested, and the power supply module 21 is connected to the end E22 and the ground measuring module 31 is connected to the end E21 to measure the waiting. Current I _{E22 is} measured. It should be noted that the number of the power supply modules and the number of the grounding measurement modules and the connection manner between the power supply module and the grounding measurement module and the end portions may be according to the needs of the user or It is adjusted for circuit layout requirements.

In summary, the surface capacitive touch panel 1' of the present invention can be obtained by using the measured eight currents to be measured at a single or multi-touch coordinate position on the panel body. In the surface capacitive touch panel 1, the surface capacitive touch panel 1' has better measurement efficiency.

Please refer to FIG. 4, which is a schematic diagram of an embodiment of measuring a current to be measured by the measuring unit of the present invention. Compared with the current value to be measured in the above embodiment, which is measured by the measuring end portion 304 of the grounding unit 302, the current value to be tested of the present invention may also be used as an amount by any point on the electrode to be tested. The measuring point (but the measuring point is different from the end of the power supply module 20 connected to the electrode to be tested) to take out the current to be measured on the electrode to be tested. The fourth electrode E4 will be described here.

Under the control of the operation control module 40, the power supply module 20 and the ground measurement module 30 are respectively connected to the end E42 and the end E41 of the fourth electrode E4 to measure the current to be measured. I _E42 . Compared with other embodiments, the measuring unit 303 of the embodiment is connected to one of the side end portions E43 of the fourth electrode E4, and the measuring point E43 is located between the end portion E41 and the end portion E42. It should be noted that the position of the measuring point E43 can be adjusted according to the circuit layout or the circuit specification requirement, and the positions other than the end portions E41 and E42 on the fourth electrode E4 can be used as the measuring point. The measuring unit 303 directly captures the current to be measured I _E42 by the measuring point E43 to measure the current value to be measured. Although the configuration of the measuring point in this embodiment generates a leakage current I _E42' , it is known to those skilled in the art that the leakage current I _E42' is much smaller than the to-be-tested. The current I _E42 , so the effect of the leakage current I _{E42 '} can be ignored. The configuration of the measuring unit 303 of the present embodiment and the control of the arithmetic control module 40 can also measure the remaining seven sets of currents I _E11 , I _E12 , I _E21 , I _E22 , I _E31 , I _E32 , I _{E41 .} And one step by the above calculation formula to calculate the coordinate position of the panel touched.

Please refer to FIG. 5 , which is a method for judging a touch coordinate position of a surface capacitive touch panel according to the present invention. The touch coordinate position determining method includes: S10: a current measurement step to be measured, and the measurement flows through the electrodes The current to be measured; S12: the total current to be measured analysis step, the sum of the waiting current is compared with a predetermined one of the total current standard value, when the sum of the waiting current is greater than the total current standard value, then proceeds to S14; S14: a central coordinate position confirmation step, wherein the center coordinate position between the plurality of touch coordinate positions is calculated by the waiting current measurement; S16: a multi-touch coordinate position confirmation step, by using the center coordinate position fitting correction, Get the position of the touch coordinates.

When the sum of the standby currents is not greater than the total current standard value, the following steps are performed: S24: Calculating a touch coordinate position by the waiting current measurement.

The invention has been described above in terms of the preferred embodiments, and it should be understood by those skilled in the art that the present invention is not intended to limit the scope of the invention. It should be noted that variations and permutations equivalent to those of the embodiments are intended to be included within the scope of the present invention. Therefore, the scope of protection of the present invention is defined by the scope of the patent application.

1‧‧‧Surface capacitive touch panel

10‧‧‧ Panel body

20‧‧‧Power supply module

201‧‧‧Power supply unit

202‧‧‧First switching unit

30‧‧‧Grounding measurement module

301‧‧‧Second switching unit

302‧‧‧ Grounding unit

303‧‧‧Measurement unit

304‧‧‧measuring end

305‧‧‧ Grounding end

40‧‧‧Operation Control Module

50‧‧‧ touch location

E1‧‧‧first electrode

E2‧‧‧second electrode

E3‧‧‧ third electrode

E4‧‧‧fourth electrode

E11, E12, E21, E22‧‧‧ end

E31, E32, E41, E42‧‧‧ end

I _E11 , I _E12 , I _E21 , I _E22 ‧‧‧ Current to be measured

I _E31 , I _E32 , I _E41 , I _E42 ‧‧‧ Current to be measured

Claims (13)

A surface capacitive touch panel includes: a panel body; four electrodes are respectively disposed on four sides of the panel body, and the electrodes individually have a first end portion and a second end portion; and a power supply module Relying to a control signal to connect one of the electrodes to select the electrode as a test electrode, and connect the power supply module to the first end of the electrode to be tested to provide a power supply to the electrode to be tested; a grounding measurement module is grounded and corresponds to the control signal, and the electrode to be tested in the electrodes is also selected, so that the grounding measurement module and the electrode to be tested are The two ends are connected to form a ground loop to measure the current to be measured flowing through the electrode to be tested and output a current value to be measured; and an operation control module is connected to the power supply module and the grounding amount Measuring the module and generating the control signal, and selecting, by the control signal, one end of each of the electrodes as the first end portion, to receive the ground measurement module separately from each of the electrodes Measuring the current value, and then calculating The touch coordinate position in each polling cycle. The surface capacitive touch panel of claim 1, wherein the power supply module comprises: a power supply unit for generating the power; and a first switching unit coupled to the power supply unit and the electrode to be tested The first end is connected, and the first switching unit is connected between the power supply unit and the electrode to be tested. The surface capacitive touch panel of claim 1 or 2, wherein the grounding measurement module comprises: a second switching unit connected to the second end of the electrode to be tested; a grounding unit, The system has a measuring end portion and a grounding end portion, the measuring end portion is connected to the second switching unit, and a measuring unit is connected to the measuring end portion to measure the to-be-tested Current value. The surface capacitive touch panel of claim 1 or 2, wherein the grounding measurement module comprises: a second switching unit connected to the second end of the electrode to be tested; a grounding unit, The system has two ends, one of the ends is connected to the second switching unit, the other of the ends is grounded, and a measuring unit is measured with one of the electrodes to be tested The points are connected to measure the current value to be measured. A surface capacitive touch panel includes: a panel body; four electrodes are respectively disposed on four sides of the panel body, and the electrodes individually have a first end portion and a second end portion; a first power source The supply module is configured to connect one of the electrodes in response to a control signal to use the electrode as a first electrode to be tested, and to make the first power supply module and the first end of the first electrode to be tested The first phase is connected to the first electrode to be tested; a first grounding measurement module is grounded and corresponds to the control signal, and the first electrode to be tested is also selected. Making the first grounding measurement module and the first The second end of the electrode to be tested is connected to form a ground loop to measure the first current to be measured flowing through the first electrode to be tested and output a first current to be measured; a second power supply module Transmitting a control signal to connect an electrode different from the first electrode to be tested as a second electrode to be tested, and connecting the second power supply module to the first end of the second electrode to be tested, Providing a second power source to the second electrode to be tested; a second grounding measurement module is grounded and corresponding to the control signal, and the second electrode to be tested is also selected to make the second The grounding measurement module is connected to the second end of the second electrode to be tested to form a ground loop to measure a second current to be measured flowing through the second electrode to be tested and output a second current to be measured And an operation control module, wherein the first power supply module, the second power supply module, the first ground measurement module, and the second ground measurement module are connected to generate the control signal, The control signal cyclically selects either end of each of the electrodes as the first end Receiving, by the first ground measurement module and the second ground measurement module, the first current to be measured and the second current to be measured respectively from the electrodes, thereby calculating each cycle The position of the touch coordinates below. The surface capacitive touch panel of claim 5, wherein the first power supply module comprises: a power supply unit that generates the power; and a first switching unit, the power supply unit and the first A first end of the electrode to be tested is connected, and the first switching unit is connected between the power supply unit and the first electrode to be tested. The surface capacitive touch panel of claim 6, wherein the first ground measurement module comprises: a second switching unit is connected to the second end of the first electrode to be tested; a grounding unit has a measuring end portion and a grounding end portion, the measuring end portion and the second switching portion The unit is connected; and a measuring unit is connected to the measuring end to measure the first current value to be tested. The surface capacitive touch panel of claim 6, wherein the first grounding measurement module comprises: a second switching unit connected to the second end of the electrode to be tested; a grounding unit, The system has two ends, one of the ends is connected to the second switching unit, the other of the ends is grounded, and a measuring unit is connected to one of the first electrodes to be tested The measuring points are connected to measure the first current value to be tested. The surface capacitive touch panel of claim 5, wherein the second power supply module comprises: a power supply unit that generates the power; and a first switching unit, the power supply unit and the first The first ends of the electrodes to be tested are connected, and the first switching unit is connected between the power supply unit and the second electrode to be tested. The surface capacitive touch panel of claim 9, wherein the second grounding measurement module comprises: a second switching unit connected to the second end of the second electrode to be tested; The unit has a measuring end portion and a grounding end portion, and the measuring end portion is connected to the second switching unit; A measuring unit is connected to the measuring end to measure the second current value to be tested. The surface capacitive touch panel of claim 9, wherein the second grounding measurement module comprises: a second switching unit connected to the second end of the electrode to be tested; a grounding unit, The system has two ends, one of the ends is connected to the second switching unit, the other of the ends is grounded, and a measuring unit is connected to one of the second electrodes to be tested The measuring points are connected to measure the second current value to be measured. A touch coordinate position determining method is used for determining a touched position on a surface capacitive touch panel according to any one of claims 1 to 8, wherein the touch coordinate position determining method comprises: S10: Measuring a current measuring step, measuring a current to be measured flowing through the electrodes; S12: a total current to be measured analyzing step, comparing the sum of the waiting currents with a predetermined one of the total current standard values, when the waiting current is measured When the sum is greater than the total current standard value, the process proceeds to S14; S14: the central coordinate position confirmation step, and the center coordinate position between the plurality of touch coordinate positions is calculated by the waiting current measurement; S16: multi-touch coordinate position confirmation In the step, the center coordinate position is fitted and corrected to obtain the touch coordinate positions. The touch coordinate position determining method as claimed in claim 12, wherein when the sum of the standby currents is not greater than the total current standard value, the process proceeds to S24: calculating a touch coordinate position by the waiting current measurement.