Correction apparatus and correction method for self-capacitive touch panel

1. A self-capacitive touch panel system, comprising:

a self-capacitive touch panel comprising a plurality of upper electrodes and a plurality of lower electrodes, the plurality of lower electrodes and upper electrodes being in a staggered arrangement along a first reference direction; and

a correction apparatus in communication with the self-capacitive touch panel, the correction apparatus including a controller configured to:

calculate a first initial coordinate in the first reference direction and a second initial coordinate in a second reference direction of a touch position according to at least one sensing result associated with the upper electrodes and at least one sensing result associated with the lower electrodes, respectively, the second reference direction being substantially perpendicular to the first reference direction;

calculate a first correction parameter in the first reference direction according to the at least one sensing result associated with the lower electrodes, and to calculate a second correction parameter in the first reference direction according to the at least one sensing result associated with the upper electrodes;

calculate a compensation amount according to the first correction parameter, the second correction parameter and the first initial coordinate; and

correct the second initial coordinate according to the compensation amount,

wherein the at least one sensing result associated with the upper electrodes comprises an N number of central capacitance changes and an M number of border capacitance changes, the at least one sensing result associated with the lower electrodes comprises a P number of central capacitance changes and a Q number of border capacitance changes, N, M, P and Q are natural numbers, and the controller calculates the first initial coordinate (x) according to an equation:

x

=

∑

i

=

1

N

⁢

⁢

(

C

i

×

X

i

)

+

∑

j

=

1

M

⁢

⁢

(

C

j

×

X

j

×

∝

1

)

+

∑

k

=

1

P

⁢

⁢

(

C

k

×

X

k

)

+

∑

l

=

1

Q

⁢

⁢

(

C

l

×

X

l

×

∝

2

)

∑

i

=

1

N

⁢

⁢

C

i

+

∑

j

=

1

M

⁢

⁢

(

C

j

×

∝

1

)

+

∑

k

=

1

P

⁢

⁢

C

k

+

∑

l

=

1

Q

⁢

⁢

(

C

l

×

∝

2

)

,

where i is an integral index ranging between 1 and N, j is an integral index ranging between 1 and M, k is an integral index ranging between 1 and P, l is an integral index ranging between 1 and Q, C i represents i th central capacitance change in the N number of central capacitance changes, X i represents a coordinate of a center of gravity corresponding to i th central capacitance change in the first reference direction X, C j represents j th border capacitance change in the M number of border capacitance changes, X j represents a coordinate of a center of gravity corresponding to j th border capacitance change in the first reference direction X, C k represents k th central capacitance change in the P number of central capacitance changes, X k represents a coordinate of a center of gravity corresponding to k th central capacitance change in the first reference direction X, C l represents l th border capacitance change in the Q number of border capacitance changes, X l represents a coordinate of a center of gravity corresponding to l th border electrode in the first reference direction X, and α1 and α2 are predetermined values; and the controller calculates the first correction parameter (x 1 ) and the second correction parameter (x 2 ) according to equations:

x

1

=

∑

k

=

1

P

⁢

⁢

(

C

k

×

X

k

)

+

∑

l

=

1

Q

⁢

⁢

(

C

l

×

X

l

)

∑

k

=

1

P

⁢

⁢

C

k

+

∑

l

=

1

Q

⁢

⁢

C

l

;

and

x

2

=

∑

i

=

1

N

⁢

⁢

(

C

i

×

X

i

)

+

∑

j

=

1

M

⁢

⁢

(

C

j

×

X

j

)

∑

i

=

1

N

⁢

⁢

C

i

+

∑

j

=

1

M

⁢

⁢

C

j

.

2. The self-capacitive touch panel system according to claim 1 , wherein a planar contour of each of the upper electrodes and each of the lower electrodes is similar to a right triangle, and the upper electrodes respectively correspond to the lower electrodes.

3. The self-capacitive touch panel system according to claim 1 , wherein the predetermined values α1 and α2 are simultaneously equal to 1 or simultaneously equal to 2.

4. The self-capacitive touch panel system according to claim 1 , wherein the controller is configured to calculate the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×b;

where w is associated with a width of one of the upper electrodes in the first reference direction, the width is an integral multiple of w, and a and b are predetermined values.

5. The self-capacitive touch panel system according to claim 1 , wherein when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a central region, the controller is configured to calculate the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×b;

when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a corner region, the controller is configured to calculate the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×c;

where w is substantially equal to a width of one of the upper electrodes in the first reference direction, a, b and c are predetermined values, and c is greater than b.

6. The self-capacitive touch panel system according to claim 1 , wherein when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a central region, the controller is configured to calculate the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×b;

when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a corner region, the controller is configured to calculate the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×c;

when the first initial coordinate and the second initial coordinate indicate that the touch position falls in an intersection region of the central region and the corner region, the controller is configured to calculate the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×d;

where w is substantially equal to a width of one of the upper electrodes in the first reference direction, a, b, c and d are predetermined values, c is greater than d, and d is greater than b.

7. A correction method for a self-capacitive touch panel having a correction apparatus including a controller, the touch panel comprising a plurality of upper electrodes and a plurality of lower electrodes, the plurality of lower electrodes and upper electrodes being in a staggered arrangement along a first reference direction, the correction method comprising the controller performing operations of:

a) calculating a first initial coordinate in the first reference direction and a second initial coordinate in a second reference direction of a touch position according to at least one sensing result associated with the upper electrodes and at least one sensing result associated with the lower electrodes, respectively, the second reference direction being substantially perpendicular to the first reference direction;

b) calculating a first correction parameter in the first reference direction according to the at least one sensing result associated with the lower electrodes;

c) calculating a second correction parameter in the first reference direction according to the at least one sensing result associated with the upper electrodes;

d) calculating a compensation amount according to the first correction parameter, the second correction parameter and the first initial coordinate; and

e) correcting the second initial coordinate according to the compensation amount,

wherein the at least one sensing result associated with the upper electrodes comprises an N number of central capacitance changes and an M number of border capacitance changes, the at least one sensing result associated with the lower electrodes comprises a P number of central capacitance changes and a Q number of border capacitance changes, N, M, P and Q are natural numbers, and operation (a) comprising calculating the first initial coordinate (x) according to an equation:

x

=

∑

i

=

1

N

⁢

⁢

(

C

i

×

X

i

)

+

∑

j

=

1

M

⁢

⁢

(

C

j

×

X

j

×

∝

1

)

+

∑

k

=

1

P

⁢

⁢

(

C

k

×

X

k

)

+

∑

l

=

1

Q

⁢

⁢

(

C

l

×

X

l

×

∝

2

)

∑

i

=

1

N

⁢

⁢

C

i

+

∑

j

=

1

M

⁢

⁢

(

C

j

×

∝

1

)

+

∑

k

=

1

P

⁢

⁢

C

k

+

∑

l

=

1

Q

⁢

⁢

(

C

l

×

∝

2

)

,

where i is an integral index ranging between 1 and N, j is an integral index ranging between 1 and M, k is an integral index ranging between 1 and P, l is an integral index ranging between 1 and Q, C i represents i th central capacitance change in the N number of central capacitance changes, X i represents a coordinate of a center of gravity corresponding to i th central capacitance change in the first reference direction X, C j represents j th border capacitance change in the M number of border capacitance changes, X j represents a coordinate of a center of gravity corresponding to j th border capacitance change in the first reference direction X, C k represents k th central capacitance change in the P number of central capacitance changes, X k represents a coordinate of a center of gravity corresponding to k th central capacitance change in the first reference direction X, C l represents l th border capacitance change in the Q number of border capacitance changes, X l represents a coordinate of a center of gravity corresponding to l th border electrode in the first reference direction X, and α1 and α2 are predetermined values; and

operation (b) to operation (c) comprise calculating the first correction parameter (x 1 ) and the second correction parameter (x 2 ) according to equations:

x

1

=

∑

k

=

1

P

⁢

⁢

(

C

k

×

X

k

)

+

∑

l

=

1

Q

⁢

⁢

(

C

l

×

X

l

)

∑

k

=

1

P

⁢

⁢

C

k

+

∑

l

=

1

Q

⁢

⁢

C

l

;

and

x

2

=

∑

i

=

1

N

⁢

⁢

(

C

i

×

X

i

)

+

∑

j

=

1

M

⁢

⁢

(

C

j

×

X

j

)

∑

i

=

1

N

⁢

⁢

C

i

+

∑

j

=

1

M

⁢

⁢

C

j

.

8. The correction method according to claim 7 , wherein a planar contour of each of the upper electrodes and each of the lower electrodes is similar to a right triangle, and the upper electrodes respectively correspond to the lower electrodes.

9. The correction method according to claim 7 , wherein the predetermined values α1 and α2 are simultaneously equal to 1 or simultaneously equal to 2.

10. The correction method according to claim 7 , wherein operation (d) comprises calculating the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×b;

where w is associated with a width of one of the upper electrodes in the first reference direction, the width is an integral multiple of w, and a and b are predetermined values.

11. The correction method according to claim 7 , wherein operation (d) comprises:

d1) when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a central region, calculating the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×b ; and

d2) when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a corner region, calculating the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×c;

where w is substantially equal to a width of one of the upper electrodes in the first reference direction, a, b and c are predetermined values, and c is greater than b.

12. The correction method according to claim 7 , wherein operation (d) comprises:

d1) when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a central region, calculating the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×b;

d2) when the first initial coordinate and the second initial coordinate indicate that the touch position falls in a corner region, calculating the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×c ; and

d3) when the first initial coordinate and the second initial coordinate indicate that the touch position falls in an intersection region of the central region and the corner region, calculating the compensation amount (comp) according to an equation:

comp=( x 1 −x 2 +w )× x×a+x 2 ×d;

where w is substantially equal to a width of one of the upper electrodes in the first reference direction, a, b, c and d are predetermined values, c is greater than d, and d is greater than b.