JP2013080344A - Touch-type input device, controller thereof, control method, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve accuracy of coordinate determination in a touch-type input device using a large-size sensor.SOLUTION: A peak detection unit 16 identifies a sensor electrode the capacitance value of which becomes maximum on the basis of a plurality of capacitance values C-Crepresenting respective electrostatic capacitances of a plurality of sensor electrodes SE, and generates peak data PEAK representing the identified sensor electrode. With respect to the sensor electrode represented by the peak data PEAK and a sensor electrode of (k-1) (k is a natural number of 2 or more) sensor electrodes selected in order from the closest to the sensor electrode represented by the peak data PEAK, when capacitance value data of i-th (1≤i≤k) sensor electrode is defined as C, an X coordinate of the i-th sensor electrode is defined as X, and a Y coordinate of the i-th sensor electrode is defined as Y, an arithmetic processing unit 18 calculates the X coordinate and the Y coordinate where a user has touched by the following expressions (1a) and (1b): (1a) x=Σ(C×X)/ΣC, and (1b) y=Σ(C×Y)/ΣC.

Description

  The present invention relates to a touch-type input device that utilizes a change in capacitance.

  Many of electronic devices such as a computer, a mobile phone terminal, and a PDA (Personal Digital Assistant) in recent years include an input device for operating the electronic device by touching with a finger.

  One of such input devices is a touch-type input device (also referred to as a touch sensor, a touch pad, or a track pad), which is a capacitance formed between an electrode and its surroundings when a user's finger comes into contact with it. It uses an electrostatic sensor that utilizes the fact that changes. The touch-type input device includes a plurality of sensor electrodes arranged in the X-axis direction, a plurality of sensor electrodes arranged in the Y-axis direction, and a detection circuit that detects the capacitance of each sensor electrode. The detection circuit determines a position touched by the user by determining a sensor electrode having a large change in capacitance, that is, a sensor electrode touched by the user.

JP 2001-325858 A Special table 2003-511799 gazette US Pat. No. 5,825,352 A1 JP 2007-013342 A Japanese Patent Laid-Open No. 11-2332034

FIG. 1A is a plan view of the panel, and FIGS. 1B and 1C are cross-sectional views of sensor electrodes and capacitance changes. The panel 4 includes a plurality of sensor electrodes SE regularly arranged in a staggered matrix. Upon contact with the sensor electrode SE _i with the user's finger, (also referred to as a peak electrode) that sensor electrode with the capacitance _{C i} of SE _i is increased, the same sensor electrode _SE i + 1 adjacent, _{SE i-1} of the capacitor _{C i- 1} and C _{i + 1} also change.

The present inventors specify the X coordinate with which the user has touched, the peak electrode SE _i having the maximum capacitance, and the capacitances C _{i of} the sensor electrodes SE _i−1 and SE _{i + 1} adjacent to the peak electrode SE _i in the X direction, A method of determining based on C _i-1 and C _{i + 1} was examined. Specifically, the coordinates C _i−1 and C _{i + 1} of the sensor electrodes SE _i−1 and SE _{i + 1} adjacent to the peak electrode SE _i are referred to, and the coordinates are determined according to which one has a large influence. For example, when the capacitance C _i−1 is substantially equal to C _{i + 1} , the coordinate x touched by the user is determined as the center of the peak electrode SE _i . When the capacitance C _i−1 is larger than C _{i + 1} , the coordinate x touched by the user is determined to be the left coordinate of the peak electrode SE _i , for example, the left end of the peak electrode SE _i .

The size of the sensor electrode varies depending on the type of panel 4. The sensor electrode SE in FIG. 1C has a larger area than the sensor electrode SE in FIG. As shown in FIG. 1B, when the size of the sensor electrode SE is small, the influence on the adjacent sensor electrodes SE _i-1 and SE _{i + 1} is large, so that their capacitance changes C _i-1 and C _{i + 1} are also somewhat. growing. Therefore, the coordinates touched by the user can be accurately calculated based on the capacities C _i−1 and C _{i + 1} .

However, as shown in FIG. 1C, when the size of the sensor electrode SE is larger than that of the finger, the influence on the adjacent sensor electrodes SE _i-1 and SE _{i + 1} is reduced, and their capacitance change C _{i− 1} , C _{i + 1} is very small. That is, it is difficult to compare the capacitors C _i-1 and C _{i + 1} . For example, even if the user's finger is in contact with the right side of the coordinate of the center of the sensor electrode SEi, the size of the sensor electrode SE is high, the capacitance change of the sensor electrode SE i _{+ 1} to the right is the left sensor electrode SE _{i Therefore} , the coordinates touched by the user are determined as the coordinates of the center of the peak electrode SE.

  2A and 2B are diagrams illustrating the operation of the touch input device having a large sensor electrode. The arrow in FIG. 2A indicates the locus of the user's finger 8. The peak electrode SE having the maximum capacity is hatched.

  The arrow in FIG. 2B indicates the locus of the user's finger 8 determined by the calculation process. As shown in FIG. 1C, when the size of the sensor electrode SE is large, the capacitance change of the sensor electrode adjacent to the peak electrode becomes minute, and it is difficult to determine the magnitude relationship between them. Therefore, the coordinates of the peak electrode are determined as the coordinates that the user touches as they are, and even when the user slides his / her finger linearly as shown in FIG. 2 (a), it is shown in FIG. 2 (b). As such, it is misrecognized as a meandering locus. That is, the linearity is deteriorated.

  The present invention has been made in view of such problems, and one of the exemplary purposes of an aspect thereof is to improve the accuracy of coordinate determination in a touch input device using a large-sized sensor.

One embodiment of the present invention relates to a controller for a touch input device. The touch-type input device has a plurality of sensor electrodes that are arranged in a two-dimensional matrix and whose capacitance changes according to the contact state of the user. The controller identifies the sensor electrode having the maximum capacitance value based on a plurality of capacitance value data indicating the capacitance of each of the plurality of sensor electrodes, and generates a peak data indicating the identified sensor electrode; , The capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode with respect to the sensor electrode indicated by the peak data and the (k−1) sensor electrodes (k is a natural number of 2 or more) selected in the closest order. Is written as C _i , the X coordinate of the i-th sensor electrode is written as X _i , and the Y coordinate of the i-th sensor electrode is written as Y _i , the X coordinate x and Y coordinate y touched by the user are expressed by the equations (1a), ( And an arithmetic processing unit that is calculated according to 1b).
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (1a)
y = Σ _{i = 1 to k} (C _i × Y _i ) / Σ _{i = 1 to k} C _i (1b)

Another aspect of the present invention also relates to a controller for a touch input device. The touch-type input device has a plurality of sensor electrodes that are arranged in the direction of the first coordinate axis and whose capacitance changes according to the contact state of the user. The controller identifies a sensor electrode having a maximum capacitance value based on a plurality of capacitance value data indicating the capacitance of each of the plurality of sensor electrodes, and generates a peak data indicating the identified sensor electrode; Regarding the k consecutive sensor electrodes (k is an integer of 2 or more) including the sensor electrode indicated by the peak data, the capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode is C _i , and the i-th sensor. when writing the coordinates of the electrode and the X _i, it comprises the coordinates x touched by the user, an arithmetic processing unit for calculating the equation (2), a.
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (2)

  In these aspects, attention is paid to the capacitance of each of the plurality of electrodes centered on the sensor electrode (peak electrode) indicated by the peak data, and the coordinates of the plurality of sensor electrodes are weighted by the capacitance. The center of gravity of the capacity is calculated. By determining the center of gravity as the coordinate touched by the user, a minute change in the capacitance of the sensor electrode around the peak electrode can be reflected in the coordinate, and the accuracy of the coordinate determination can be improved.

The arithmetic processing unit may decrease the value of k as the number of sensor electrodes having peaks detected by the peak detection unit increases.
In a multi-touch state in which the user touches the panel at a plurality of points, the capacitance of the sensor electrode around a certain finger changes due to the influence of another finger, so that an error occurs in the coordinate determination at each contact location. Therefore, when a plurality of peaks are detected, the influence of other contact points can be reduced by reducing the number k of surrounding sensor electrodes to be taken into consideration when performing coordinate determination.

The arithmetic processing unit may change the value of k according to the distance of the sensor electrode having the peak detected by the peak detection unit.
When the user touches a plurality of points, the influence of the interaction is considered to be small if the distances are some distance apart. Therefore, the coordinates can be accurately determined by increasing k when the distance is large and decreasing k when the distance is close.

When the minimum value of the X coordinate is x _min and the maximum value is x _max , four coordinates x1 to x4 that satisfy x _min <x1 <x2 <x3 <x4 <x _max may be defined. The touch-type input device of a certain aspect: (i) When x1 <x <x2, the coordinate x is transformed into a coordinate x ′ in the range of x _min <x ′ <x2, and (ii) x2 <x <x3 when, as a raw value coordinates x, when (iii) x3 <x <x4, the coordinates x x3 <x may further comprise a coordinate transformation unit for coordinate conversion _'<coordinate x in the range of _{x max'} .

Furthermore the minimum value of the Y coordinate _{y min,} when the maximum value is _{y max,} may be defined y min <y1 <y2 <y3 <y4 <4 single coordinate satisfying _{x max} y1 to y4. At this time, the coordinate conversion unit (iv) converts the coordinate y to the coordinate y ′ in the range y _min <y ′ <y2 when y1 <y <y2, and (v) when y2 <y <y3 The coordinate y may be used as it is, and (vi) when y3 <y <y4, the coordinate y may be converted to the coordinate y ′ in the range of y3 <y ′ <y _max .

  The electrode near the outermost periphery of the panel has no electrode adjacent to the outside. Therefore, the coordinates determined by the above-described coordinate determination method tend to shift to the inside of the panel from the actual correct coordinates. By converting the coordinates x1 to x2, x3 to x4, y1 to y2, and y3 to y4 in the vicinity of the outer periphery, the coordinates can be brought close to the correct coordinates.

  Another aspect of the present invention relates to a touch input device. The input device includes a panel and the controller according to any one of the above aspects.

  Another embodiment of the present invention relates to an electronic device. The electronic device includes the above-described input device.

  It should be noted that any combination of the above-described constituent elements and the expression of the present invention converted between methods, apparatuses, etc. are also effective as an aspect of the present invention.

  According to an aspect of the present invention, the accuracy of coordinate determination can be improved in a touch input device using a large-sized sensor.

1A and 1B are cross-sectional views of the sensor electrode and a diagram showing a change in capacitance. 2A and 2B are diagrams illustrating the operation of the touch input device having a large sensor electrode. It is a block diagram which shows the structure of an electronic device provided with the touch-type input device which concerns on embodiment. It is a block diagram which shows the structure of the input device which concerns on embodiment. It is a figure for demonstrating the process of an arithmetic processing part. 6A and 6B are diagrams illustrating the operation of the input device. It is a figure which shows operation | movement of a coordinate transformation part. It is a figure which shows another structural example of a sensor part.

  The present invention will be described below based on preferred embodiments with reference to the drawings. The same or equivalent components, members, and processes shown in the drawings are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate. The embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  FIG. 3 is a block diagram illustrating a configuration of the electronic device 1 including the touch-type input device 2 according to the embodiment. The input device (touch type input device) 2 is disposed, for example, at a position overlapping with an LCD (Liquid Crystal Display) 9, that is, on the surface layer of the LCD 9, and functions as a touch panel. Alternatively, it may be an input device such as a trackpad arranged at a different location from the LCD 9.

  The input device 2 includes a sensor unit 4, a capacitance detection circuit 10, and a panel controller 6. When the user touches the surface of the sensor unit 4 with the finger 8, a sensor electrode (not shown) arranged inside the sensor unit 4 is deformed or displaced, and the capacitance formed between the electrode and the surroundings changes. . The sensor unit 4 has an array of a plurality of sensor electrodes arranged in a staggered matrix. Note that the capacitance detection circuit 10 and the panel controller 6 may be configured integrally.

  The capacitance detection circuit 10 detects a change in the capacitance of the sensor electrode and outputs data corresponding to the detection result to the panel controller 6. The panel controller 6 is a so-called DSP (Digital Signal Processor), analyzes data from the capacitance detection circuit 10, and determines the presence / absence and type of a user input operation. For example, when the user's finger 8 touches the sensor unit 4, selection of an item or object displayed on the LCD 9 is selected, or character input is assisted.

  Plan views of the sensor unit 4 are shown in FIGS. 2A and 2B, and a plurality of sensor electrodes SE are arranged in a matrix. The method of arranging the sensor electrodes is not particularly limited. When the user touches the sensor unit 4 with a finger, the capacitance of the sensor electrode SE immediately below the finger changes. When a plurality of user's fingers come into contact, the capacitance of the sensor electrode SE immediately below each finger changes. Further, the capacitance of the sensor electrode SE around the sensor electrode SE immediately below the finger also changes slightly.

FIG. 4 is a block diagram illustrating a configuration of the input device 2 according to the embodiment. The input device 2 includes a plurality of sensor electrodes SE _{i, j} , a capacitance detection circuit 10, a peak detection unit 16, and an arithmetic processing unit 18. As described above, the plurality of sensor electrodes SE _{i, j} are arranged in a matrix. The subscripts _{i and j} indicate an element in the i-th row and the j-th column.

The capacitance detection circuit 10 is connected to a plurality of sensor electrodes SE _{1,1 to} SEM _{, N} , measures the capacitance of each sensor electrode SE _{i, j} , and capacitance value data C indicating the measured capacitance. Generate an array of _{i, j} .

The panel controller 6 includes a peak detection unit 16, a calculation processing unit 18, and a coordinate conversion unit 20. The peak detection unit 16 specifies the sensor electrode SE _PEAK having the maximum capacitance value based on the plurality of capacitance value data C _{1,1 to} C _{M, N} and generates peak data PEAK indicating the specified sensor electrode SE _PEAK. To do. When there are a plurality of peaks, data indicating each peak is generated.

The arithmetic processing unit 18 selects the sensor electrode SE _PEAK indicated by the peak data PEAK, and (k−1) sensor electrodes (k is a natural number of 2 or more) in order from the sensor electrode SE _PEAK, and sets them as calculation targets. The arithmetic processing unit 18 then regards the capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode as C _i , the X coordinate of the i-th sensor electrode as X _i , and the i-th as for the selected k sensor electrodes. When the Y coordinate of the sensor electrode is written as Y _i , the X coordinate x and Y coordinate y touched by the user are calculated based on the equations (1a) and (1b).
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (1a)
y = Σ _{i = 1 to k} (C _i × Y _i ) / Σ _{i = 1 to k} C _i (1b)

Expressions (1a) and (1b) indicate that the coordinates of the plurality of sensor electrodes are weighted by the capacitance of each of the plurality of k electrodes centered on the sensor electrode (peak electrode) SE _PEAK indicated by the peak data PEAK. means. This is nothing but computing the center of gravity of the capacitance.

FIG. 5 is a diagram for explaining the processing of the arithmetic processing unit 18. FIG. 5 shows a case where k = 25. The number 1 is assigned to the peak electrode SE _PEAK, and the numbers 2 to 25 are assigned in order from the peak. FIG. 5 shows the X and Y coordinates of each sensor electrode SE. For example, the X coordinate X ₁ of the _first sensor electrode (peak electrode SE _PEAK ) is 5, the Y coordinate Y ₁ is 6, the X coordinate X ₁₀ of the _10th sensor electrode SE is 3, and the Y coordinate Y ₁₀ is 4. is there.

The arithmetic processing unit 18 is configured so that the parameter k can be switched. In the first mode, k = 25, k = 13 in the second mode, k = 9 in the third mode, and k = 5 in the fifth mode.
The coordinate conversion unit 20 will be described later.

  The above is the configuration of the input device 2 related to coordinate detection. Next, the operation will be described.

6A and 6B are diagrams illustrating the operation of the input device 2.
The arrow in FIG. 6A indicates the locus of the user's finger 8. The peak electrode SE _PEAK having the maximum capacity is hatched. In FIG. 6B, dots are given to the sensor electrodes SE that are the targets of the calculations (1a) and (1b) by the calculation processing unit 18. FIG. 6B shows processing in the third mode (k = 9). When the sensor electrode SEa is a peak sensor, k = 9 sensor electrodes centered on the peak sensor SEa, which are surrounded by the rectangle A, are subjected to arithmetic processing of the expressions (1a) and (1b).
When the sensor electrode SEb is a peak sensor, k = 9 sensor electrodes centered on the peak sensor SEb surrounded by the rectangle B are subjected to arithmetic processing of the expressions (1a) and (1b).

  As the peak sensor SE moves, the trajectory of the user's finger 8 determined by the arithmetic processing by determining the coordinates at each time by the arithmetic expressions (1a) and (1b) is shown in FIG. It becomes a straight line as shown by an arrow. This coincides with the actual trajectory of the finger 8 shown in FIG.

According to the input device 2 according to the embodiment, a minute capacitance change of the sensor electrode around the peak electrode can be reflected in the coordinates, and the accuracy of the coordinate determination can be improved.
In order to clarify the effect of the input device 2 according to the embodiment, the method of the input device 2 is compared with the method (referred to as a comparison technique) shown in FIGS. Here, attention is paid to the determination of the X coordinate.

In the comparative technique, the X coordinate is determined based on the capacitance of the 6th sensor electrode on the left and the 8th sensor electrode on the right in addition to the 1st peak sensor SE _PEAK in FIG. On the other hand, in the embodiment, when k = 5, the X coordinate is determined based on the capacities of the second, third, fourth, and fifth sensor electrodes in addition to the peak sensor SE _PEAK . That is, in the input device 2, the number of sensors excluding the peak sensor used for coordinate determination is at least twice that of the comparison technique.

  Further, as is apparent from FIG. 5, the distance between No. 2 and No. 1 (the distance between No. 5 and No. 1) is shorter than the distance between No. 6 and No. 1. Therefore, when No. 1 is the peak sensor, the capacitance change that occurs in the No. 2 to No. 4 sensors is larger than the No. 6 and No. 8 capacitance changes.

  From the above, according to the input device 2, in the comparison technique, the X coordinate is determined with higher accuracy than the determination of the X coordinate according to the equation (1a) using the sensors of No. 1, No. 6, and No. 8. The X coordinate can be determined. The same applies to the Y coordinate.

  The arithmetic processing unit 18 may dynamically control the mode, that is, the parameter k. Hereinafter, mode control will be described.

1. First Control In a multi-touch state where the user touches the panel at a plurality of points, the capacitance of the sensor electrode around one finger can change due to the influence of another finger. If it does so, an error will arise in the coordinate judgment of each contact location. In this case, the arithmetic processing unit 18 may decrease the value of k as the number of sensor electrodes having peaks detected by the peak detection unit 16 increases. That is, the mode may be switched according to the number of peaks. When a plurality of peaks are detected, by reducing the number k of surrounding sensor electrodes to be taken into consideration when performing coordinate determination, the influence of other fingers can be reduced and correct coordinate determination can be performed.

  In actual use, single touch is often used in situations where accurate coordinate detection is required, such as character input or drawing of figures, while multi-touch is used for gesture input and so on. There are many situations where coordinate detection is not required. Therefore, even if the parameter k is reduced during multi-touch, there is no significant disadvantage.

2. Second Control In a multi-touch state, when the distance between fingers is large, the interaction between fingers is considered small. Therefore, the arithmetic processing unit 18 may change the value of k in accordance with the distance between the plurality of sensor electrodes having the peaks detected by the peak detection unit 16. Even when the user touches a plurality of points, if the distance between the two points is large, the coordinates can be accurately determined by increasing k.

3. Third control When the finger touches the panel, the influence on the surroundings is large, and when the finger touches with the pen, the influence on the surroundings is small. Therefore, the arithmetic processing unit 18 determines the object (object) that contacts the sensor electrode, that is, dynamically changes the mode depending on whether the finger touches the panel or the pen. You may control to. A known algorithm may be used as the algorithm for determining the object.

Next, the coordinate conversion unit 20 will be described.
FIG. 7 is a diagram illustrating the operation of the coordinate conversion unit 20.
The sensor electrode near the outermost periphery of the panel 4 has no electrode adjacent to the outside. Therefore, the coordinates determined by the arithmetic processing unit 18 based on the equations (1a) and (1b) tend to shift to the inside of the panel from the actual correct coordinates. Therefore, the coordinates x and y determined by the arithmetic processing unit 18 are limited to an area inside the rectangle C, for example.

When the minimum value of the X coordinate of the panel 4 is x _min and the maximum value is x _max , four coordinates x1 to x4 satisfying x _min <x1 <x2 <x3 <x4 <x _max are defined. x1 may correspond to the X coordinate of the left side of the rectangle C, and x3 may correspond to the X coordinate of the right side of the rectangle C, or may be a coordinate close thereto. Similarly, the minimum value of the Y coordinate of the panel 4 when _{y min,} the maximum value is _{y max, y min <y1 <} y2 <y3 <y4 <4 single coordinate satisfying _{x max} y1 to y4 are defined. y1 may correspond to the Y coordinate of the lower side of the rectangle C, and y3 may correspond to the Y coordinate of the upper side of the rectangle C, or may be a coordinate close thereto.

The coordinate conversion unit 20 converts the coordinate x to the coordinate x ′ in the range of x _min <x ′ <x2 when (i) x1 <x <x2, and (ii) the coordinate when x2 <x <x3 the x and as values to coordinate conversion (iii) x3 <when x <x4, the coordinates x x3 <x _'<coordinate x in the range of _{x max'.}

Similarly, the coordinate conversion unit (iv) converts the coordinate y to the coordinate y ′ in the range y _min <y ′ <y2 when y1 <y <y2, and (v) when y2 <y <y3, The coordinate y may be used as it is, and (vi) when y3 <y <y4, the coordinate y may be converted to a coordinate y ′ in a range of y3 <y ′ <y _max .

  The coordinate conversion unit 20 outputs the coordinates x and y generated by the arithmetic processing unit 18 as they are inside the rectangle D surrounded by (x2, x3, y2, y3). That is, x = x ′ and y = y ′.

On the other hand, the coordinates of the area outside the rectangle D and inside the rectangle C are coordinate-converted to the area outside the rectangle D and inside the outer periphery of the sensor unit 4. The method of coordinate transformation is not particularly limited, and linear transformation may be performed or a complicated algorithm may be used.
By converting the coordinates x1 to x2, x3 to x4, y1 to y2, and y3 to y4 in the vicinity of the outer circumference, the coordinates can be brought close to the correct coordinates, and the coordinates of the area outside the area C can be detected. Note that x1 to x4 and y1 to y4 preferably define different sets for each mode (parameter k).

  Although the present invention has been described using specific words and phrases based on the embodiments, the embodiments are merely illustrative of the principles and applications of the present invention, and the embodiments are defined in the claims. Many modifications and arrangements can be made without departing from the spirit of the present invention.

In the embodiment, the case where the sensor electrodes SE are arranged in a matrix has been described, but the present invention is not limited thereto.
FIG. 8 is a diagram illustrating another configuration example of the sensor unit 4. 8 includes a plurality of sensor electrodes (column electrodes) SE _COL arranged in the first coordinate axis direction (X direction) and a plurality of sensor electrodes (column electrodes) SE _COL arranged in the second coordinate axis direction (Y direction). A sensor electrode (row electrode) SE _ROW is provided.

The capacitance detection circuit 10 generates capacitance value data Cx _{1 to} Cx ₄ indicating the capacitance of each of the plurality of column electrodes SE _COL and capacitance value data Cy _{1 to} Cy ₅ indicating the capacitance of each of the plurality of row electrodes SE _ROW .

The panel controller 6 determines the X coordinate based on the capacitance value data Cx _{1 to} Cx ₄ and determines the Y coordinate based on the capacitance value data Cy _{1 to} Cy ₅ .

Since the determination processing of the X coordinate and the Y coordinate is the same, the X coordinate will be described below.
The peak detector 16 detects the X-direction peak electrode SE _PEAKx based on the capacitance value data Cx _{1 to} Cx ₄ . The arithmetic processing unit 18 performs capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode with respect to continuous k sensor electrodes (k is an integer of 2 or more) including the peak electrode SE _PEAKx indicated by the peak data. Is expressed as Cx _i , and the coordinate of the i-th sensor electrode is written as X _i , the coordinate x touched by the user is calculated by Equation (2). The peak electrode SE _PEAKx is preferably at the center of k consecutive sensor electrodes.
x = Σ _{i = 1 to k} (Cx _i × X _i ) / Σ _{i = 1 to k} Cx _i (2)

The same applies to the Y coordinate, which is calculated based on Equation (3).
y = Σ _{i = 1 to k} (Cy _i × Y _i ) / Σ _{i = 1 to k} Cy _i (3)

  According to this modification, it is possible to accurately detect the X coordinate and the Y coordinate even for the panel of FIG. Moreover, even when using the panel of FIG. 8, the coordinate of the outer peripheral part of the panel 4 is correctly detectable by using the coordinate conversion part 20 together.

  The configuration of the panel is not particularly limited, and may be a configuration other than those shown in FIGS. The present invention is applicable to coordinate detection of a panel including a plurality of sensor electrodes arranged at least in the first direction.

DESCRIPTION OF SYMBOLS 1 ... Electronic device, 2 ... Input device, 4 ... Sensor part, 5 ... Shield electrode, 6 ... Panel controller, 7 ... Reference electrode, 8 ... Finger, 9 ... LCD, 10 ... Capacitance detection circuit, 12 ... C / V conversion Circuit, 14 ... A / D conversion circuit, 16 ... Peak detection unit, 18 ... Arithmetic processing unit, 20 ... Coordinate conversion unit, SE ... Sensor electrode.

Claims (11)

A controller of a touch-type input device that has a plurality of sensor electrodes that are arranged in a two-dimensional matrix and whose capacitance changes according to the contact state of the user,
Based on a plurality of capacitance value data indicating the capacitance of each of the plurality of sensor electrodes, a peak detection unit that identifies the sensor electrode having a maximum capacitance value and generates peak data indicating the identified sensor electrode;
Capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode with respect to the sensor electrode indicated by the peak data and (k−1) (k is a natural number of 2 or more) sensor electrodes selected in order from the sensor electrode. C _i , the X coordinate of the i-th sensor electrode is written as X _i , and the Y coordinate of the i-th sensor electrode is written as Y _i , the X coordinate and Y coordinate touched by the user are expressed by the equations (1a) and (1b).
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (1a)
y = Σ _{i = 1 to k} (C _i × Y _i ) / Σ _{i = 1 to k} C _i (1b)
An arithmetic processing unit calculated by
A controller comprising: A controller of a touch input device having a plurality of sensor electrodes arranged in the direction of a first coordinate axis, each of which changes in capacitance according to a contact state of a user,
Based on a plurality of capacitance value data indicating the capacitance of each of the plurality of sensor electrodes, a peak detection unit that identifies the sensor electrode having a maximum capacitance value and generates peak data indicating the identified sensor electrode;
With respect to k consecutive sensor electrodes (k is an integer of 2 or more) including the sensor electrode indicated by the peak data, the capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode is C _i , i-th When the coordinate of the sensor electrode is written as X _i , the coordinate x touched by the user is expressed by equation (2).
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (2)
An arithmetic processing unit calculated by
A controller comprising:   The controller according to claim 1, wherein the arithmetic processing unit decreases the value of k as the number of sensor electrodes having peaks detected by the peak detection unit increases.   The controller according to claim 3, wherein the arithmetic processing unit changes a value of k in accordance with a distance between a plurality of sensor electrodes having a peak detected by the peak detection unit.   The controller according to claim 3, wherein the arithmetic processing unit changes a value of k in accordance with an object in contact with the sensor electrode. When the minimum value of the X coordinate is x _min and the maximum value is x _max , four coordinates x1 to x4 that satisfy x _min <x1 <x2 <x3 <x4 <x _max are defined,
(I) When x1 <x <x2, the coordinate x is converted to a coordinate x ′ in the range of x _min <x ′ <x2, and (ii) when x2 <x <x3, the coordinate x is left as it is. (Iii) When x3 <x <x4, further comprising a coordinate conversion unit for converting the coordinate x into a coordinate x ′ in a range of x3 <x ′ <x _max. The controller described in Crab. When the minimum value of the X coordinate is x _min and the maximum value is x _max , four coordinates x1 to x4 that satisfy x _min <x1 <x2 <x3 <x4 <x _max are defined,
The minimum value of the Y coordinate _{y min,} when the maximum value is _{y max,} defines a y min <y1 <y2 <y3 <y4 <4 single coordinate satisfying _{x max} y1 to y4,
(I) When x1 <x <x2, the coordinate x is converted to a coordinate x ′ in the range of x _min <x ′ <x2, and (ii) when x2 <x <x3, the coordinate x is left as it is. (Iii) When x3 <x <x4, the coordinate x is converted to a coordinate x ′ in the range of x3 <x ′ <x _max . (Iv) When y1 <y <y2, the coordinate y is set to y _min <Y ′ <y2 in the range of coordinates y ′, (v) when y2 <y <y3, the coordinate y is the same value, and (vi) when y3 <y <y4, the coordinate y is y3 The controller according to claim 1, further comprising a coordinate conversion unit that converts coordinates to a coordinate y ′ in a range of <y ′ <y _max .   A touch input device comprising the controller according to claim 1.   An electronic apparatus comprising the controller according to claim 1. A control method for a touch input device that has a plurality of sensor electrodes that are arranged in a two-dimensional matrix and whose capacitance changes according to the contact state of a user,
Measuring a capacitance of each of the plurality of sensor electrodes, and generating a plurality of capacitance value data indicating the measured capacitance;
Identifying the sensor electrode having a maximum capacitance value based on the plurality of capacitance value data;
The capacitance of the i-th (1 ≦ i ≦ k) sensor electrode with respect to the sensor electrode having the maximum capacitance value and (k−1) (k is a natural number of 2 or more) sensor electrodes selected in the order closest thereto. When the value data is C _i , the X coordinate of the i-th sensor electrode is written as X _i , and the Y coordinate of the i-th sensor electrode is written as Y _i , the X coordinate and Y coordinate touched by the user are expressed by the equations (1a), ( 1b)
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (1a)
y = Σ _{i = 1 to k} (C _i × Y _i ) / Σ _{i = 1 to k} C _i (1b)
A step of calculating by
A method comprising the steps of: A method for controlling a touch input device having a plurality of sensor electrodes arranged in the direction of a first coordinate axis and having respective capacitances that change in accordance with a user's contact state,
Measuring a capacitance of each of the plurality of sensor electrodes, and generating a plurality of capacitance value data indicating the measured capacitance;
Identifying the sensor electrode having a maximum capacitance value based on the plurality of capacitance value data;
For the k consecutive sensor electrodes including the sensor electrode having the maximum capacitance value (k is an integer of 2 or more), the capacitance value data of the i-th (1 ≦ i ≦ k) sensor electrode is expressed as C _i , i When the coordinate of the second sensor electrode is written as X _i , the coordinate x touched by the user is expressed by equation (2).
x = Σ _{i = 1 to k} (C _i × X _i ) / Σ _{i = 1 to k} C _i (2)
A step of calculating by
A method comprising the steps of:

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