CN103809829A - Touch boundary non-linear recognition correction method based on capacitive touch screen - Google Patents

Abstract

Provided is a touch boundary non-linear recognition correction method based on a capacitive touch screen. The effect of finger locating recognition is improved when a finger for touch is located in a touch screen boundary area, and then recognition linearity of the finger for touching the touch screen boundary area is improved; meanwhile, the touch screen boundary area where a finger recognition point can reach can be close to the boundary zero point to the greatest extent, and the defect that due to the lack of a sidelobe induction measuring signal, deviation can exist in the process of leading out an accurate finger position value is effectively overcome.

Description

Touch border identification of nonlinearity antidote based on capacitance touch screen

Technical field

The invention belongs to capacitance touch screen technical field, be specifically related to a kind of touch border identification of nonlinearity antidote based on capacitance touch screen.

Background technology

Capacitance touch screen is widely used in mobile phone and the such industrial circle of panel computer at present, such as the equipment that is 800*480 concerning a display resolution, the actual sensed haptic element of its capacitance plate is but little, and corresponding with the quantity of responding to feeler is touch resolution.If touch resolution is set as to K*L at this, total line number in the resolution territory that wherein K is capacitance touch screen, L is total columns in the resolution territory of capacitance touch screen, and K and L are all greater than zero, the induced signal of the sensed position of the energy of inside, resolution territory just can be expressed as D(m*n like this), wherein m is the integer that is less than or equal to K, and n is the integer that is less than or equal to L, and D(m*n) just represent the induced signal of the position sensed for the energy of the capable longitudinal n row of horizontal m in resolution territory.After the touch-screen in this resolution territory being carried out to the sampling of induced signal, through certain conversion, can the derive signaling point in the display resolution territory of calculating and be mapped to another 800*480, this signaling point is exactly the accurate touch point of finger on touch-screen, form thus the signal output of the identification point that finger touch forms on touch-screen, in concrete practical operation, D(m*n) the basic central point producing for finger touch, namely signal maximum point (or being referred to as extreme point), then the position, touch point of pointing more accurately on touch-screen needs the cooperation of periphery induced signal to derive, it is the participation of the induced signal of so-called nearly extreme point, because induced signal point is at a distance noise substantially, do not need to participate in this derivation process.Conventionally point the touch sensible signal D (m, n) on touch-screen and need the horizontal and vertical arrangement position of the periphery induced signal coordinating as follows:

D(m-1,n-1) D(m-1,n) D(m-1,n+1)

D(m,n-1) D(m,n) D(m,n+1)

D(m+1,n-1) D(m+1,n) D(m+1,n+1)

Like this in the method for derivation touch point, use horizontal periphery induced signal scope combination to derive the horizontal exact position Px of finger, use longitudinal periphery induced signal scope combination to derive longitudinal exact position Py, no matter be namely horizontal or longitudinal, the Main Basis of deriving precise local fix is that main lobe (is exactly D (m, n) this extreme point) and secondary lobe, in general situation, Px be with 3 induced signals be D (m, n-1), D (m, and D (m n), n+1) derive, Py be with 3 induced signals be D (m-1, n), D (m, and D (m+1 n), n) derive, the method deriving mainly contains parabolic method, or centroid method, or its mutation method.Any method derives the original signal of Px or Py, and as above surface analysis, all derives from three continuous samplings, no matter is D (m, n-1), D (m, n), D (m, n+1) or D (m-1, n), D (m, n), D (m+1, n),, for convenient, unification is here described as D (i-1), D (i), three numerical value of D (i+1), Px or Py unification are described as P.The basic skills of asking for center of mass point (accurately pointing a little) is shown in formula (1):

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is actually Px or Py, and Px is the horizontal exact position, touch point of deriving, and Py is longitudinal exact position, touch point of deriving, and i is extreme point position, is laterally n, is longitudinally m; D (i) is exactly D (m, n), it is laterally D (m that D (i-1) represents, n-1) be or longitudinally D (m-1, n), D (i+1) expression is laterally D (m, n+1) or is longitudinally D (m+1, n), can obtain similar equation expression by parabolic method equally.

When said method under general condition calculates, be that in the time that sensed data extreme point is placed in the middle, to derive effect fine, at this moment the data on both sides, D (i-1) or all physical presence of D (i+1), but in the time that finger arrives at any one borderline region of four borderline regions of touch-screen, no matter be coboundary, lower boundary, left margin or right margin, this effect just becomes a kind of feature of " clamper ".Obviously, in the time that finger arrives at the left margin of touch-screen or coboundary, D (i-1) has disappeared; In the time that finger arrives at the right margin of touch-screen or lower boundary, D (i+1) has disappeared.

Sort signal, in the disappearance of borderline region, makes centroid method during this time produce distortion by the signal that the method for formula (1) derives above.First the signal of this disappearance cannot supplement automatically, because the particular location of the signal and the finger that disappear is relevant, not have the signal of disappearance not have associated with known two; , if according to the method for formula (1), will inevitably there is D (i-1)=0 or D (i+1)=0 at Boundary Region in the secondly result of this blackout; At this moment formula (1) can alienation become following formula (2) and formula (3):

$P=\frac{D\left(i\right)*+D(i+1)*(i+1)}{D\left(i\right)+D(i+1)}---\left(2\right)$

$P=\frac{D(i-1)*(i-1)+D\left(i\right)*i}{D(i-1)+D\left(i\right)}---\left(3\right)$

What formula (2) was described here is the situation of left margin or coboundary alienation, and what formula (3) was described is the situation of right margin or lower boundary alienation, and the sort signal variation bringing to finger point accurate position calculation that disappears is clearly.Give an example, if finger arrives a kind of privileged site, cause in three induced signal samplings, the signal on both sides is the same, has D (i-1)=D (i+1), and according to formula (1), the position of the accurate finger obtaining is formula (4-1):

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}=i---(4-1)$

That is to say that finger is positioned at the middle of the measurement of inductance position of extreme point.But at borderline region, even if finger has reached same position, finger is positioned at the middle of measurement of inductance position, owing to lacking a secondary lobe measurement of inductance signal, will there is deviation in the derivation of finger position value accurately.

Summary of the invention

The invention provides a kind of touch border identification of nonlinearity antidote based on capacitance touch screen, the effect of the finger fixation and recognition when finger that improvement touches is positioned at touch-screen borderline region, and then raising finger touch is in the identification linearity of touch-screen borderline region, make to point the borderline region of the touch-screen that identification point can arrive simultaneously, low border 0 point that approaches of trying one's best, has avoided causing the derivation of finger position exact value to occur the defect of deviation owing to lacking a secondary lobe measurement of inductance signal effectively.

For achieving the above object, technical scheme of the present invention is:

A touch border identification of nonlinearity antidote based on capacitance touch screen, step is as follows:

Step 1: when finger is still on touch-screen, point the position sampling signal on touch-screen by the capacitance inductor collection on touch-screen, and the position sampling signal on touch-screen sends in processor the finger collecting, no matter processor is horizontal or longitudinal like this, all obtain position sampling signal D (i-1), D (i) and D (i+1), D (i) is the extreme point of the finger that the collects position sampling signal on touch-screen, D (i-1) is for this extreme point is on the corresponding row left side or list the signal on limit, D (i+1) is for this extreme point is on corresponding row the right or be listed as following signal.In position sampled signal D (i-1), D (i) and D (i+1), there is D(0) and D(1) in the situation that, if when the value of D (0) is less than the value of D (1), processor judges that finger touch point is not or not touch-screen border, processor just utilizes formula (1) to derive finger touch point at the exact position of touch-screen P like this, and formula (1) is as follows:

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is Px or Py, and Px is the horizontal exact position, touch point of the finger of derivation, and Py is longitudinal exact position, touch point of the finger of derivation, and i is extreme point position.If when the value of D (0) is not less than the value of D (1), processor judges that finger touch point is on touch-screen border, and processor just utilizes formula (4) to derive the touch point of pointing in the coboundary of touch-screen or the exact position P of left margin like this; And processor utilizes touch point that formula (5) derives finger at the lower boundary of touch-screen or the exact position P of right margin:

$P=\frac{D\left(0\right)*D\left(0\right)*0+D\left(1\right)*D\left(1\right)*1}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}=\frac{D\left(1\right)*D\left(1\right)}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}---\left(4\right)$

$P=\frac{D(M-2)*D(M-2)*(M-2)+D(M-1)*(M-1)*(M-1)}{D(M-2)*D(M-2)+D(M-1)*D(M-1)}\text{---}\left(5\right)$

M is total line number K or total columns L in the resolution territory of capacitance touch screen,

And processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P in the time that i is not 0;

Step 2: in the time that finger moves on touch-screen, point the position sampling signal in the time that touch-screen moves by the capacitance inductor Real-time Collection on touch-screen, and the position sampling signal on touch-screen sends in processor the finger collecting, no matter processor is horizontal or longitudinal like this, all obtain position sampling signal D (i-1), D (i) and D (i+1), D (i) is the extreme point of the finger that the collects position sampling signal on touch-screen, D (i-1) is for this extreme point is on the corresponding row left side or list the signal on limit, D (i+1) is for this extreme point is on corresponding row the right or be listed as following signal, at position sampled signal D (i-1), in D (i) and D (i+1), there is D(0) and situation D(1) under, if when the value of D (0) is less than the value of D (1), processor judges that finger touch point is not or not touch-screen border, processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P like this, formula (1) is as follows:

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is Px or Py, and Px is the horizontal exact position, touch point of the finger of derivation, and Py is longitudinal exact position, touch point of the finger of derivation, and i is extreme point position; If when the value of D (0) is not less than the value of D (1), processor judges that finger touch point is on touch-screen border, and processor just utilizes formula (4) to derive the touch point of pointing in the coboundary of touch-screen or the exact position P of left margin like this; And processor utilizes touch point that formula (5) derives finger at the lower boundary of touch-screen or the exact position P of right margin:

$P=\frac{D\left(0\right)*D\left(0\right)*0+D\left(1\right)*D\left(1\right)*1}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}=\frac{D\left(1\right)*D\left(1\right)}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}---\left(4\right)$

$P=\frac{D(M-2)*D(M-2)*(M-2)+D(M-1)*(M-1)*(M-1)}{D(M-2)*D(M-2)+D(M-1)*D(M-1)}\text{---}\left(5\right)$

M is total line number K or total columns L in the resolution territory of capacitance touch screen,

And processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P in the time that i is not 0.

Advantage of the present invention is as follows:

(1) the method can arrive (coboundary when borderline region at finger, lower boundary, left margin and right margin), find the approach that more approaches tram, rather than as shown in formula (2) or formula (3), due to the disappearance naturally of sideband signal, make the finger touch position of deriving have very large deviation.

(2) the method will guarantee that finger is in moving process, and particularly, in the process of shifting to border, the improvement of method can not affect its finger derives the continuity of position, that is to say, the process of shifting to border there will not be the dead band of deriving result;

(3) the method will guarantee that finger is in moving process, and particularly, in the process of shifting to border, the improvement of method can not change the monotonicity of its moving direction; That is to say, the direction of shifting to border there will not be and turns to.

Accompanying drawing explanation

Fig. 1 is the signal schematic representation of D of the present invention (i-1), D (i) and D (i+1).

Fig. 2 is D(0 of the present invention), D(1) and signal schematic representation D(2).

Fig. 3 is D(-1 of the present invention), D(0), D(1) and signal schematic representation D(2).

Specific implementation method

Algorithm described in the invention, its purpose of design is carried out nonlinear properties processing at borderline region exactly, makes its accuracy of identification approach actual position as far as possible.

Below by specific embodiment, the present invention will be further described:

Shown in Fig. 1, Fig. 2 and Fig. 3, the touch border identification of nonlinearity antidote based on capacitance touch screen of the present invention, step is as follows:

Step 1: in the time that finger is still on touch-screen, point the position sampling signal on touch-screen by the capacitance inductor collection on touch-screen, and the position sampling signal on touch-screen sends in processor the finger collecting, no matter processor is horizontal or longitudinal like this, all obtain position sampling signal D (i-1), D (i) and D (i+1), D (i) is the extreme point of the finger that the collects position sampling signal on touch-screen, D (i-1) is for this extreme point is on the corresponding row left side or list the signal on limit, D (i+1) is for this extreme point is on corresponding row the right or be listed as following signal.In position sampled signal D (i-1), D (i) and D (i+1), there is D(0) and D(1) in the situation that, if when the value of D (0) is less than the value of D (1), processor judges that finger touch point is not or not touch-screen border, processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P like this, and formula (1) is as follows:

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is Px or Py, and Px is the horizontal exact position, touch point of the finger of derivation, and Py is longitudinal exact position, touch point of the finger of derivation, and i is extreme point position.If when the value of D (0) is not less than the value of D (1), processor judges that finger touch point is on touch-screen border, and processor just utilizes formula (4) to derive the touch point of pointing in the coboundary of touch-screen or the exact position P of left margin like this; As a same reason, processor utilizes touch point that formula (5) derives finger at the lower boundary of touch-screen or the exact position P of right margin:

$P=\frac{D\left(0\right)*D\left(0\right)*0+D\left(1\right)*D\left(1\right)*1}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}=\frac{D\left(1\right)*D\left(1\right)}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}---\left(4\right)$

$P=\frac{D(M-2)*D(M-2)*(M-2)+D(M-1)*(M-1)*(M-1)}{D(M-2)*D(M-2)+D(M-1)*D(M-1)}\text{---}\left(5\right)$

M is total line number K or total columns L in the resolution territory of capacitance touch screen,

And processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P in the time that i is not 0; In the time that i is not 0, the feature of sort signal is: the D (i) in the middle of being positioned at is maximum value, namely main lobe, and D (i-1) and D (i+1) are less than main lobe data D (i) as secondary lobe, its signal is exported as shown in Figure 1.Certainly,, along with the movement of finger, no matter longitudinally still laterally the value of the i in D (i),, all may change.

Step 2: in the time that finger moves in touch-screen, i value in described D (i), the extreme point position that is position sampled signal will change, the position sampling signal that this variation is pointed on touch-screen by the capacitance inductor collection on touch-screen completes, obviously migrate to the process of touch-screen boundary position more and more convergence border of this i value from touch-screen centre position at finger.

In the time that finger touch approaches touch-screen left margin, laterally i value more and more approaches 0;

In the time that finger touch approaches touch-screen coboundary, longitudinally i value more and more approaches 0;

In the time that finger touch approaches touch-screen right margin, laterally i value more and more approaches (L-1), total columns of the location sensitive signal that L is touch-screen;

In the time that finger touch approaches touch-screen lower boundary, longitudinally i value more and more approaches (K-1), total line number of the location sensitive signal that K is touch-screen;

In this time, still can calculate finger touch exact position with formula (1).

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

Further in the time that finger touch point approaches the left margin of touch-screen or coboundary, point in the shift position of touch-screen sampled signal by the capacitance inductor collection on touch-screen, and the finger collecting is sent in processor in the shift position of touch-screen sampled signal, processor is in the time that finger touch point approaches the left margin of touch-screen or coboundary like this, just can on the left side circle horizontal or coboundary obtain shift position sampled signal D (0) on longitudinally, D (1) and D (2), wherein D (1) is extreme point, in this moment, D (0) and D (2) are less than D (1).At this moment described D (1) is for finger touch point is at the extreme point of this signal stream, D (0) is the first row (left margin) of this that a line of extreme point, or the signal of the first row (coboundary) of those row of this extreme point, D (2) is the 3rd row (left margin) of this that a line of extreme point, or the signal of the third line (coboundary) of those row of this extreme point.Finger touch point is in the left margin or coboundary process that approach touch-screen, and horizontal or longitudinal data can change.Along with constantly move to left margin or coboundary on touch-screen finger touch position, point in the shift position of touch-screen sampled signal by the capacitance inductor collection on touch-screen, and the finger collecting is sent in processor in the sampled signal of the shift position of touch-screen, like this processor (left margin) laterally or (coboundary) all obtained shift position sampled signal D (0), D (1) and D (2) on longitudinally, wherein the Changing Pattern of each data is: the value of D (0) is increasing; The value of D (1) is more and more less; The value of D (2) is also more and more less, and it is also smaller to compare D (1), because finger is more from away from more; The trend that sort signal changes is continuous to Boundary Moving according to finger touch point on touch-screen.Under the condition of D (0) <D (1), the decline of the rising of D (0) and D (1) causes a state to be bound to occur that is exactly D (0)=D (1), and is all greater than D (2).This state is actually the state of finger touch in the middle of two inductions (or driving) line.Continue in the process of touch-screen Boundary Moving at finger, D (0) is increasing, and D (1) is more and more less, has a moment, and D (0) has become new extreme point.At this moment D (2) value becomes very little, can be not counted in, and D (1) is the data of disappearance simultaneously, as shown in Figure 3.Due to the disappearance naturally of D (1), the process that processor utilizes formula (1) to derive the exact position of the touch point of finger will become formula (2) like this; As a same reason, the derived expression of lower boundary or right margin becomes formula (3), and causing like this deriving error will significantly depart from.

$P=\frac{D\left(i\right)*i+D(i+1)*(i+1)}{D\left(i\right)+D(i+1)}---\left(2\right)$

$P=\frac{D(i-1)*(i-1)+D\left(i\right)*i}{D(i-1)+D\left(i\right)}---\left(3\right)$

Under this condition, the processor adopting nonlinear method in the present invention, shown in following formula (4), proofreaies and correct the basic physical location near touch-screen on the left side circle or coboundary of the finger recognizing site obtaining thus, improves identification accuracy.

$P=\frac{D\left(0\right)*D\left(0\right)*0+D\left(1\right)*D\left(1\right)*1}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}=\frac{D\left(1\right)*D\left(1\right)}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}---\left(4\right)$ 。

In the time that finger moves to lower boundary or right margin in the middle part of touch-screen, point the position sampling signal in the time that touch-screen moves by the capacitance inductor Real-time Collection on touch-screen, and the finger collecting is sent in processor at the position sampling signal of touch-screen, processor laterally or is longitudinally all obtaining position sampling signal D (i-1) like this, D (i) and D (i+1), D (i) is for the finger that collects is at the extreme point of the position sampling signal of touch-screen, D (i-1) is for this extreme point point is on the corresponding row left side or list the signal on limit, D (i+1) is for this extreme point is on corresponding row the right or be listed as following signal, processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P like this, formula (1) is as follows:

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is Px or Py, Px is the horizontal exact position, touch point of the finger of derivation, Py is longitudinal exact position, touch point of the finger of derivation, i is extreme point position, same this class borderline region, use similar non-linear correction, processor utilizes touch point that formula (5) derives finger at the lower boundary of touch-screen or the exact position P of right margin:

$P=\frac{D(M-2)*D(M-2)*(M-2)+D(M-1)*(M-1)*(M-1)}{D(M-2)*D(M-2)+D(M-1)*D(M-1)}\text{---}\left(5\right)$

M is total line number K or total columns L in the resolution territory of capacitance touch screen,

And processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P in the time that i is not 0.

Use said method, the display screen that the touch-screen that mapping induction feeler is 15X10 is 800X480 to corresponding resolution, such as near borderline region boundary on top, extreme point D(0 under general condition) be its secondary lobe D(1) five times, use the value of the boundary position that the method for prior art derives to be

and use the value of the boundary position of method derivation of the present invention to be

With respect to prior art

result: the display screen that is 800 × 480 for display resolution, demonstration gap point=(1/6) * (800/15)=8.89 on long limit, approaches 9 and shows points;

With respect to

result: the display screen that is 800X480 for display resolution, demonstration gap point=(1/26) * (800/15)=2.05 on long limit, approaches 2 and shows points;

As can be seen here, method of the present invention effectively reduces error, and display is grown 2 the demonstration points that drop on limit, and it is acceptable scope that this display error touches effect to finger at touch-screen borderline region in engineering.

The above, it is only preferred embodiment of the present invention, not the present invention is done to any pro forma restriction, although the present invention discloses as above with preferred embodiment, but not in order to limit the present invention, any those skilled in the art, do not departing within the scope of technical solution of the present invention, when can utilizing the technology contents of above-mentioned announcement to make a little change or being modified to the equivalent embodiment of equivalent variations, in every case be not depart from technical solution of the present invention content, according to technical spirit of the present invention, within the spirit and principles in the present invention, the any simple modification that above embodiment is done, be equal to replacement and improvement etc., within all still belonging to the protection domain of technical solution of the present invention.

Claims (1)

1. the touch border identification of nonlinearity antidote based on capacitance touch screen, is characterized in that, step is as follows:

Step 1: when finger is still on touch-screen, point the position sampling signal on touch-screen by the capacitance inductor collection on touch-screen, and the position sampling signal on touch-screen sends in processor the finger collecting, no matter processor is horizontal or longitudinal like this, all obtain position sampling signal D (i-1), D (i) and D (i+1), D (i) is the extreme point of the finger that the collects position sampling signal on touch-screen, D (i-1) is for this extreme point is on the corresponding row left side or list the signal on limit, D (i+1) is for this extreme point is on corresponding row the right or be listed as following signal, in position sampled signal D (i-1), D (i) and D (i+1), there is D(0) and D(1) in the situation that, if when the value of D (0) is less than the value of D (1), processor judges that finger touch point is not or not touch-screen border, processor just utilizes formula (1) to derive finger touch point at the exact position of touch-screen P like this, and formula (1) is as follows:

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is Px or Py, and Px is the horizontal exact position, touch point of the finger of derivation, and Py is longitudinal exact position, touch point of the finger of derivation, and i is extreme point position; If when the value of D (0) is not less than the value of D (1), processor judges that finger touch point is on touch-screen border, and processor just utilizes formula (4) to derive the touch point of pointing in the coboundary of touch-screen or the exact position P of left margin like this; And processor utilizes touch point that formula (5) derives finger at the lower boundary of touch-screen or the exact position P of right margin:

$P=\frac{D\left(0\right)*D\left(0\right)*0+D\left(1\right)*D\left(1\right)*1}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}=\frac{D\left(1\right)*D\left(1\right)}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}---\left(4\right)$

$P=\frac{D(M-2)*D(M-2)*(M-2)+D(M-1)*(M-1)*(M-1)}{D(M-2)*D(M-2)+D(M-1)*D(M-1)}\text{---}\left(5\right)$

M is total line number K or total columns L in the resolution territory of capacitance touch screen,

And processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P in the time that i is not 0;

Step 2: in the time that finger moves on touch-screen, point the position sampling signal in the time that touch-screen moves by the capacitance inductor Real-time Collection on touch-screen, and the position sampling signal on touch-screen sends in processor the finger collecting, no matter processor is horizontal or longitudinal like this, all obtain position sampling signal D (i-1), D (i) and D (i+1), D (i) is the extreme point of the finger that the collects position sampling signal on touch-screen, D (i-1) is for this extreme point is on the corresponding row left side or list the signal on limit, D (i+1) is for this extreme point is on corresponding row the right or be listed as following signal, at position sampled signal D (i-1), in D (i) and D (i+1), there is D(0) and situation D(1) under, if when the value of D (0) is less than the value of D (1), processor judges that finger touch point is not or not touch-screen border, processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P like this, formula (1) is as follows:

$P=\frac{D(i-1)*(i-1)+D\left(\text{i}\right)*i+D(i+1)*(i+1)}{D(i-1)+D\left(i\right)+D(i+1)}---\left(1\right)$

P in formula (1) is Px or Py, and Px is the horizontal exact position, touch point of the finger of derivation, and Py is longitudinal exact position, touch point of the finger of derivation, and i is extreme point position; If when the value of D (0) is not less than the value of D (1), processor judges that finger touch point is on touch-screen border, and processor just utilizes formula (4) to derive the touch point of pointing in the coboundary of touch-screen or the exact position P of left margin like this; And processor utilizes touch point that formula (5) derives finger at the lower boundary of touch-screen or the exact position P of right margin:

$P=\frac{D\left(0\right)*D\left(0\right)*0+D\left(1\right)*D\left(1\right)*1}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}=\frac{D\left(1\right)*D\left(1\right)}{D\left(0\right)*D\left(0\right)+D\left(1\right)*D\left(1\right)}---\left(4\right)$

$P=\frac{D(M-2)*D(M-2)*(M-2)+D(M-1)*(M-1)*(M-1)}{D(M-2)*D(M-2)+D(M-1)*D(M-1)}\text{---}\left(5\right)$

M is total line number K or total columns L in the resolution territory of capacitance touch screen,

And processor just utilizes formula (1) to derive the touch point of pointing at the exact position of touch-screen P in the time that i is not 0.

Images