JP2013073576A - Coordinate input system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinate detection system having a diagonal coordinate calculation method for correcting an influence of an external resistance component.SOLUTION: A coordinate input system includes: a linear resistive peripheral electrode 13 having equal resistance values per unit length; detection electrodes 14 to 17 arranged at four vertices of a rectangular coordinate input area 18 so as to be electrically brought into contact with the resistive peripheral electrode 13; current measurement means for measuring currents flowing in the four detection electrodes 14 to 17; coordinate calculation means for, when a position in the coordinate input area 18 is pointed with a finger 21, calculating a position in the coordinate input area 18 pointed with the finger 21 from values of currents running through the four detection electrodes 14 to 17; and determination and recognition means for determining whether one point is pointed with one finger 21 or two different points are pointed with two fingers 21 in the coordinate input area 18 from the values of currents running through the four detection electrodes 14 to 17, and for, when it is determined that the two points are pointed with the two fingers 21, recognizing a relative motion performed by the two fingers 21.

Description

The present invention relates to a coordinate input system that detects a position touched by a finger, a so-called touch panel.

FIG. 10 shows a coordinate input panel 1 having a conventional rectangular coordinate input area 8, and a resistive surrounding surrounding the surface resistor 2 so as to be electrically connected to the uniform surface resistor 2. An electrode 3 is disposed, and detection electrodes 4, 5, 6, and 7 are provided at four vertices. The detection electrodes 4, 5, 6, and 7 are electrically connected to the resistive surrounding electrode 3. The coordinate input area 8 is on the surface resistor 2 and inside the resistive surrounding electrode 3.
As a coordinate detection method of the coordinate input system using the coordinate input panel 1, the entire surface resistor 2 is vibrated by voltage, and the position of the point designated by the finger is obtained on the input panel side through capacitive coupling or direct contact. There is a method to detect with. For example, the current value distributed to four vertices (4, 5, 6, and 7) of the current entering and exiting one point of the surface resistor 2 is measured, and the coordinates are calculated based on these current values Is known (see Japanese Patent No. 3237629 (Patent Document 1)). A coordinate input system using such a method is called a surface-type touch panel.
“Instructing” a “point” with a finger means touching a point corresponding to a certain position coordinate in the coordinate input area 8 with the finger.
In the surface type touch panel as described above, when the same coordinate input area is simultaneously indicated by a plurality of fingers, the coordinates of the position indicated by each finger are calculated based on the current values flowing through the four vertices. It is said that it is impossible to do. For applications that require such a function, a projection capacitive touch panel in which electrodes are arranged vertically and horizontally in a coordinate input area, an engineering touch panel using a camera, and the like are used.
However, in Japanese Patent Application Laid-Open No. 2010-157029 (Patent Document 2) by the applicant of the present application, even if it is a surface-type coordinate input system having a rectangular coordinate input region and having detection electrodes at four vertices of the rectangle, It is disclosed that it is possible to identify whether one point is designated with one finger or two different points are designated with two fingers in the coordinate input area.
On the other hand, as one of the uses of the touch panel, there is a gesture input. In this method, a specific command is transmitted to a subsequent apparatus to which the coordinate input system is connected by the movement of a finger indicating the inside of the coordinate input area. Some gestures are realized by a single finger, but with the spread of touch panels capable of multi-touch in recent years, gestures using a plurality of fingers have been used.

Japanese Patent No. 3237629 Japanese Patent Laid-Open No. 2010-157029

Compared with the projection type, for example, the surface type touch panel has the advantage that the position of the plurality of fingers cannot be calculated, but the panel structure is simple and the number of wirings is very small. Further, as described above, in the surface-type touch panel, when a plurality of fingers are instructed at the same time, it is impossible to individually calculate the coordinates of all positions designated by the respective fingers. However, in the case of gesture recognition, it is only necessary to be able to recognize the relative relationship of each position indicated by each finger and the change in the relative relationship, and it is not essential to individually obtain the coordinates of all the positions specified by each finger. Exists.
The present invention has been made in consideration of such points, and provides a coordinate input system that can detect information related to a gesture when simultaneously instructing with two fingers while being a surface-type coordinate input system. The purpose is to do.

According to the present invention, at least a rectangular coordinate input area having a single surface resistor formed thereon and a rectangular coordinate input area and four sides constituting the outer edge of the rectangular coordinate input area are in electrical contact with the surface resistor. A linear resistive peripheral electrode provided with a constant resistance value per unit length and at least equal resistance values per unit length between opposing sides, and four rectangular coordinate input areas A detection electrode provided at the apex so as to be in electrical contact with the resistive surrounding electrode, a current measuring means for measuring a current flowing through the four detection electrodes, and a position in the coordinate input area are indicated with a finger The coordinate calculation means for calculating the position in the coordinate input area indicated by the finger from the current values flowing through the four detection electrodes, and the coordinate input from the current values flowing through the four detection electrodes. Point one point with one finger in the area If two fingers are pointing to two different points, and if two fingers are pointed to indicate two points, the two fingers are performing The gist of the present invention is a coordinate input system having identification recognition means for recognizing relative motion.

According to the coordinate input system of the present invention, it is possible to recognize a part of a gesture using a plurality of fingers on a surface-type touch panel having a simple panel structure as compared with the projection type.
Also, for relatively large touch panels that are not good at projection type, for example, the camera system recognizes part of the gesture using multiple fingers without increasing the thickness of the frame on the surface side of the panel. can do.

Schematic diagram showing the first embodiment Diagram showing coordinate system Schematic diagram explaining the enlargement and reduction gestures Schematic diagram explaining the two-finger scroll gesture Schematic diagram explaining the rotation gesture Schematic diagram of the coordinate input panel of Example 1 Experimental results of the coordinate input system of Example 1 Experimental results of the coordinate input system of Example 2 Experimental results of the coordinate input system of Example 3 Conventional rectangular coordinate input panel

Hereinafter, preferred embodiments of a coordinate correction method according to the present invention will be described in detail with reference to the accompanying drawings.
<First Embodiment>
FIG. 1 is a schematic diagram illustrating an example of a coordinate input system according to the first embodiment. 2 is a configuration diagram of a coordinate input system that detects a position ((X, Y) coordinates) designated by a finger 21 in a coordinate input area 18 of a coordinate input panel 11. FIG. The surface resistor 12 is uniformly formed on one surface of transparent glass, resin, or opaque insulating base material by coating, vapor deposition, or the like. The surface of the surface resistor 12 may be insulated so that the finger 21 does not directly touch the surface resistor 12, thereby transmitting a signal by capacitive coupling between the finger 21 and the surface resistor 12. However, the signal may be transmitted by direct electrical contact between the finger 21 and the surface resistor 12 without performing an insulation process. Here, the case where the insulation process is performed on the surface of the surface resistor 12 will be described.
A rectangular resistive surrounding electrode 13 with each side being a straight line is disposed in close contact with or around the uniform surface resistor 12, and the inside of the region surrounded by the resistive surrounding electrode 13 is defined as a rectangular coordinate input region 18. . On the resistive surrounding electrode 13, the positions corresponding to the four vertices of the rectangular coordinate input region 18 are set as the detection electrodes 14 to 17, and lead lines 22 to 25 are connected to the detection electrodes 14 to 17 respectively. The lead lines 22 to 25 generally include external resistance components 26 to 29, respectively. The lead wires 22 to 25 are connected to the oscillating voltage application circuit 31 in the analog signal processing unit 30.
When detecting the coordinates, the oscillating voltage generator 32 as an AC signal source applies an oscillating voltage to the oscillating voltage application circuit 31, and the oscillating voltage application circuit 31 causes the detection electrodes 14 to 17 to vibrate with low impedance, and The current flowing from the detection electrodes 14 to 17 to the analog multiplexer 33 is output. As a simple example, a transistor base is vibrated by an AC signal, an emitter is connected to a detection electrode, and a current is output from a collector.
The entire surface of the surface resistor 12 is vibrated by the vibration voltage generator 32 serving as an AC signal source. As is known in the art, the human body has a grounding effect on the AC signal. When the human finger 21 contacts or approaches the surface resistor 12, the surface resistor is passed through the fingertip by capacitive coupling. AC signal current flows between The detection electrodes 14 to 17 are connected to an A / D converter (analog / digital converter) 34 through an analog multiplexer 33, and a voltage proportional to the current flowing through each detection electrode is applied to the A / D converter 34. For this reason, the value of the current flowing from the fingertip through the surface resistor 12 and distributed to the detection electrodes 14 to 17 can be obtained as a digital value as a digital value.
The CPU 35 sequentially switches the analog multiplexer 33 (not shown), inputs the digital value output from the A / D converter 34, and calculates the coordinates of the indicated position of the finger 21 by a method as will be described later. Further, the CPU 35 identifies whether one or two fingers are in contact with or close to the surface resistor 12 based on the digital values output from the A / D converter 34 and their temporal changes. Then, when it is identified that there are two, it tries to recognize the relative movement performed by the two fingers as a gesture. The CPU 35 outputs the calculated coordinates and / or recognized gestures as data, and the coordinates and gestures are used by a subsequent apparatus.
The surface resistor 12 is made of an opaque carbon film, a transparent ITO (indium tin oxide) film formed by sputtering, a NESA (tin oxide) film formed by CVD, or the like uniformly on a substrate. The film is formed, and the surface resistance is preferably about 1 KΩ / □. For example, soda glass can be used as the substrate, but the material is not particularly limited, and any glass material or a transparent resin material such as an acrylic resin or a polyethylene resin can be used. Depending on the application, an opaque insulating substrate may be used.
A rectangular resistive surrounding electrode 13 whose sides are straight is provided around or inside the single-connected sheet resistor 12 so that all sides are in electrical contact with the sheet resistor 12. Here, the single connection means that the surface resistor 12 has a shape such that there is no isolated hole in the interior, and is connected to one another. However, as long as it does not hinder the macroscopic flow of current inside the surface resistor 12, such as a hole about the size of a pinhole generated on the surface resistor 12 according to the film formation method, It doesn't matter at all. Further, when a larger hole is generated due to an injury or the like, the coordinates are distorted according to the size of the hole at least around the hole, but the influence on the coordinate calculation of the indicated position of the finger 21 is small as the distance from the hole is increased. Therefore, if the hole is small, there is no practical problem.
The resistive surrounding electrode 13 surrounding the surface resistor 12 is formed by closely arranging carbon, silver carbon, silver, or the like. For example, a technique such as screen printing and baking of conductive ink such as silver ink is used. Create with. Each side of the resistive surrounding electrode 13 may be a straight line having a width, or low resistance conductive elements are arranged separately from each other and formed by utilizing the resistance of the surface resistor 12. But you can. The resistive surrounding electrode 13 makes the resistance value per length constant for each side, and at least equals the resistance value per length of the upper and lower sides of the rectangle and the resistance value per length of the left and right sides.
Further, the resistance value of the resistive surrounding electrode 13 is preferably lower than the resistance value of the sheet resistor 12. When the sheet resistance value of the sheet resistor 12 is about 1 KΩ / □, The resistance value between adjacent vertices is preferably about 20 to 200Ω.
The detection electrodes 14 to 17 at the respective apexes are for connecting lead wires, and are formed by printing and baking a solderable conductive ink. When the same conductive ink as the resistive surrounding electrode 13 can be used as the conductive ink for forming the detecting electrodes 14 to 17, the detecting electrodes 14 to 17 and the resistive surrounding electrode 13 are It is possible to form by printing and baking by processing.
The external resistance components 26 to 29 are the total of the resistance components included in elements such as the resistances of the lead wires 22 to 25 and the oscillating voltage application circuit 31 for each path emanating from each of the detection electrodes 14 to 17. Generally, the resistance inherent in the lead lines 22 to 25 occupies a large portion of them.
In the case of using sufficiently low resistance lead wires or the like as the lead wires 22 to 25, the external resistance components 26 to 29 are extremely smaller than the resistance value of the resistive surrounding electrode 13, and in calculating the coordinates, It will not be necessary to consider it independently. On the other hand, for example, when the extension of the lead wires 22 to 25 is long or the resistance is relatively high depending on the material and shape of the lead wires 22 to 25, the external resistance components 26 to 29 become large. Further, in order to collect the cables connecting the coordinate input panel 11 and the analog signal processing unit 30, the coordinate input panel 11 is connected to the outside of the resistive surrounding electrode 13 on the coordinate input panel 11 from each of the detection electrodes 14 to 17. Even when a conductive pattern is formed up to an arbitrary position on the outer periphery, the external resistance components 26 to 29 increase depending on the conductive ink to be used, the thickness of the pattern, etc. The pattern is regarded as a part of the lead lines 22 to 25). In particular, when the conductive pattern is printed with the same conductive ink as the resistive surrounding electrode 13 so as not to increase the number of times of printing, the resistance values of the external resistance components 26 to 29 and the resistance value of the resistive surrounding electrode 13 are set. The ratio is a low ratio of almost several times depending on the thickness of the pattern.
When the resistance value of the resistive surrounding electrode 13 or the external resistance components 26 to 29 is not sufficiently lower than the resistance value of the surface resistor 12, the coordinates of the indicated position of the finger 21 calculated by the method described later are There is a tendency to shift toward the inside of the panel as compared to the actual pointing position. In such a case, it is necessary to correct the coordinates according to the magnitude of the resistance value.
The resistive surrounding electrode 13 has a finite width because it needs to be formed by a technique such as printing and to connect the lead wires 22 to 25 to the detection electrodes 14 to 17. At this time, at least at the boundary line between the resistive surrounding electrode 13 and the sheet resistor 12, the resistive surrounding electrode 13 and the sheet resistor 12 need to be in electrical contact. Usually, the resistive surrounding electrode 13 is formed after the surface resistor 12 is formed. However, the surface resistor 12 may protrude outside the resistive surrounding electrode 13. Also in this case, the coordinate input area 18 is inside the area surrounded by the resistive surrounding electrode 13.
The shape of the resistive surrounding electrode 13 and the surface resistor 12 may be any shape as long as it can be accommodated in the substrate, and the shape of the resistive ambient electrode 13 and the sheet resistor 12 and the substrate need not be substantially matched. It is preferable that the shape of the base electrode is the same as the shape of the surrounding electrode 13 and the surface resistor 12 because the degree of freedom in designing the incorporated product is increased when the coordinate input system is incorporated into any product. When a conductive pattern is formed outside the resistive surrounding electrode 13 as a part of the lead wires 22 to 25, it is necessary to prevent the sheet resistor 12 from overlapping the conductive pattern.
Next, a method for calculating the coordinates of the designated position of the finger 21 will be described. “Instructing” “point” with the finger 21 means that the point corresponding to a certain position coordinate in the coordinate input area 18 is touched with the finger.
Further, “touching” means that the finger 21 is in contact with or close to the insulation processing portion on the surface resistor 12. The strength of capacitive coupling between the finger 21 and the surface resistor 12 varies depending on the area and distance between the two. Therefore, the total value of the currents flowing through the detection electrodes 14 to 17 is monitored, and it is determined that the touch is made when the total value exceeds a predetermined threshold value.
FIG. 2 shows a rectangular coordinate input area 18 and an orthogonal coordinate system XY for calculating coordinates. For convenience, the four vertices of the rectangle are named, and the vertices corresponding to the detection electrodes 14 to 17 are called vertices AD. The orthogonal coordinate system XY is an orthogonal coordinate system set in an arbitrary positional relationship with respect to the rectangular coordinate input area 18 according to the convenience of the user, and the origin is set with respect to the rectangular coordinate input area 18. Arbitrary positions can be taken and the X axis can be taken in any direction. If the offset of the coordinate system with respect to the center of the rectangular coordinate input area 18 is known, and if the inclination of the X axis with respect to any side of the rectangular coordinate input area 18 is known, a final affine transformation is performed. Thus, the coordinates of an arbitrary orthogonal coordinate system XY can be obtained. In the present embodiment, for the sake of explanation, as shown in FIG. 2, the origin of the orthogonal coordinate system XY is made the same as the center of the rectangular coordinate input area 18, and the X axis is set to the side AB of the rectangular coordinate input area 18. Although the case of parallel is taken as an example, the configuration is not limited to this relationship.
Now, when the finger 21 is touching the coordinate input area 18 of the coordinate input panel 11, the current flowing to the detection electrode 14 (vertex A) out of the current flowing from the fingertip to the coordinate input panel 11 through the surface resistor 12. The value measured by the A / D converter 35 is measured value A, the value measured by the current flowing through the detection electrode 15 (vertex B) is measured B, and the value measured by the current flowing through the detection electrode 16 (vertex C) is measured. A value C and a value obtained by measuring the current flowing through the detection electrode 17 (vertex D) are defined as a measured value D.
At this time, the coordinates (X, Y) of the position indicated by the finger 21 can be obtained by the following formula 1 in the orthogonal coordinate system XY if the resistance values of the external resistance components 26 to 29 are set to 0. Are known. a and b represent distances from the origin to the boundary of the coordinate input area 18 in the X direction and the Y direction, respectively, when the center of the coordinate input area 18 is the origin. However, as will be described later, the relationship between a and b can be changed as appropriate by adjusting the relationship between the resistance value per length of the upper and lower sides and the resistance value per length of the left and right sides.

もし、２本の指でそれぞれ異なる２点を指示している場合、数式１によって計算される座標（Ｘ，Ｙ）は、２本の指で指示している２点を結ぶ直線上になる。２本の指の、面抵抗体１２との間の静電容量結合の強さが互いに等しければ、数式１によって計算される座標は、２本の指で指示している２点を結ぶ直線をちょうど２分する中間点になる。静電容量結合の強さが互いに等しくなければ、数式１によって計算される座標は、２本の指で指示している２点を結ぶ直線上の、静電容量結合の強さがより強い指が指示している方に近い位置になる。
本願出願人による特開２０１０−１５７０２９号（特許文献２）には、１本の指で１点を指示している場合、Ａ×Ｃ＝Ｂ×Ｄ（つまりＡ×Ｃ−Ｂ×Ｄ＝０）が成立するが、２本の指でそれぞれ異なる２点を指示している場合には成立しない、ということが開示されている。更に詳細に調べた結果、２本の指でそれぞれ異なる２点を指示している場合には、次に示す数式２が成立することが分かった。ただし、第１の指が指示している位置の座標を（Ｘ_１，Ｙ_１）、測定値Ａのうち、第１の指による分の数値をＡ_１（以下Ｂ、Ｃ、Ｄについても同様）、また、第２の指が指示している位置の座標を（Ｘ_２，Ｙ_２）、測定値Ａのうち、第２の指による分の数値をＡ_２（以下Ｂ、Ｃ、Ｄについても同様）とする。

If two different points are indicated by two fingers, the coordinates (X, Y) calculated by Equation 1 are on a straight line connecting the two points indicated by the two fingers. If the strength of the capacitive coupling between the two fingers and the surface resistor 12 is equal to each other, the coordinates calculated by Equation 1 are a straight line connecting the two points indicated by the two fingers. It will be a halfway point that just bisects. If the strengths of the capacitive couplings are not equal to each other, the coordinates calculated by Equation 1 are those on the straight line connecting the two points indicated by the two fingers and having stronger capacitive coupling strengths. The position is closer to the direction indicated by.
In Japanese Patent Application Laid-Open No. 2010-157029 (Patent Document 2) by the applicant of the present application, when one point is indicated by one finger, A × C = B × D (that is, A × C−B × D = 0). ) Is established, but it is not established when two different points are indicated by two fingers. As a result of further detailed investigation, it was found that the following Expression 2 is established when two different points are indicated by two fingers. However, the coordinates of the position pointed to by the first finger are (X ₁ , Y ₁ ), and among the measured values A, the numerical value for the first finger is A ₁ (hereinafter also the same for B, C, and D). ), And the coordinates of the position indicated by the second finger are (X ₂ , Y ₂ ), and among the measured values A, the numerical value for the second finger is A ₂ (hereinafter B, C, D) The same).

測定の結果得られるのはＡ（＝Ａ_１＋Ａ_２）（及びＢ、Ｃ、Ｄ）であり、個別のＡ_１及びＡ_２は不可知である。従って、（Ｘ_１，Ｙ_１）及び（Ｘ_２，Ｙ_２）を求めることはできない。しかし、数式２は、Ａ×Ｃ−Ｂ×Ｄが０でなければ、タッチしているのが複数の指である、と判断してよいことを示すものである。また、Ａ×Ｃ−Ｂ×Ｄは、（Ｘ_１−Ｘ_２）×（Ｙ_１−Ｙ_２）を含むため、２本の指でそれぞれ異なる２点を指示している場合、２点間の距離が離れていればいるほど、０から離れた数値となる。ただし、（Ｘ_１−Ｘ_２）×（Ｙ_１−Ｙ_２）の形であるため、２本の指でそれぞれ異なる２点を指示していても、その２点を結ぶ直線が、ＸＹ座標系に対して水平もしくは垂直である場合、数式２は０になり、タッチしているのが２本の指であることを識別できなくなることには、注意する必要がある。
また、タッチしている指が３本以上の場合には、Ａ×Ｃ−Ｂ×Ｄが０になる条件が増加する上、Ａ×Ｃ−Ｂ×Ｄの数値から複数の指の位置関係を読み取るのが困難になるため、本出願では、タッチする指は１本もしくは２本に限定する。
数式２を用いて認識できるジェスチャとしては、次のようなものがある。例えば、まず、２本の指で、座標入力パネル１１の座標入力領域１８内の略同じ点を指示する（図３（ａ）、座標入力パネル１１にタッチしているのは指先である）。その後、２本の指を、タッチしたまま、座標入力領域１８内の対角方向に向けて、互いに離していく（図３（ｂ））。このような相対運動は、一般的に、拡大を意味するジェスチャとして知られている。
このとき、数式１によって計算される座標は、２本の指で指示している２点を結ぶ直線上になる。ある使用者が、例えば、両手の人差し指を用い、同じ程度の強さで２点にタッチしていて、同じような速度で指を離していっていれば、２本の指がタッチしたまま離れていく間も、数式１によって計算される座標は、２本の指で指示している２点を結ぶ直線を略２分する中間点を示し続ける。一方、２本の指が指示している点同士の間隔が広がっていくに従って、Ａ×Ｃ−Ｂ×Ｄは、その絶対値が、０から次第に大きくなっていく。
これらのことから、数式１によって計算された座標が時間的にそれほど変化せず、一方でＡ×Ｃ−Ｂ×Ｄが時間の経過とともに大きくなっていく場合には、一般的に拡大を意味するジェスチャがなされたと認識することができる。また、Ａ×Ｃ−Ｂ×Ｄは、図２のＸＹ座標系において、２本の指が指示している２点の位置関係が右下がりであれば正に、右上がりであれば負になるため、２種類の拡大ジェスチャを識別することができる。
ただし、２本の指を互いに離す方向を、水平方向もしくは垂直方向とすると、前記したように、２本の指でそれぞれ異なる点を指示しているときでも、Ａ×Ｃ−Ｂ×Ｄが０となってしまうため、２本の指でタッチしているということを識別できない。このため、２本の指を互いに離す方向は、斜めにする必要があり、（Ｘ_１−Ｘ_２）×（Ｙ_１−Ｙ_２）の形であることから、ＸＹ座標系において＋４５度もしくは−４５度方向が最も好ましい。
また、１本の指で１点を指示している場合、Ａ×Ｃ−Ｂ×Ｄは、理論的には常に０であるはずであった。しかし、測定値を用いて、Ａ×Ｃ−Ｂ×Ｄを実際に計算してみると、特に、長方形の座標入力領域１８の４頂点に近づくほど、Ａ×Ｃ−Ｂ×Ｄが０から離れる傾向があることが分かった。従って、前記のジェスチャについて、数式１によって計算される座標が、座標入力領域１８の４頂点の近傍になるような位置における操作は、タッチしている指が１本であるか２本であるかを識別しにくくなるため、好ましくない。
このことから、拡大のジェスチャについて、数式１によって計算される座標が座標入力領域１８の中央付近になるようにするのが特に好ましい。つまり、検出可能な拡大のジェスチャとしては、２本の指で、座標入力領域１８内部のうち、少なくとも抵抗性周囲電極１３の近傍を除外した略同じ点をまず指示し、その後、２本の指を、それぞれが指示する点を結ぶ直線の傾きが、少なくとも水平及び垂直でないように、最も好ましくは＋４５度もしくは−４５度方向に近い傾きであるよう、広げていく、というものに限定される。
このジェスチャについては、ジェスチャの開始時には、２本の指が略同じ点を指示しているため、１本ではなく２本の指がタッチしている、ということを識別できない。２本の指が指示する点がある程度離れて初めて、２本の指がそれぞれ異なる点を指示している、ということを認識できる。また、それ以降は、２本の指が指示する点の間の距離が大きいほど、Ａ×Ｃ−Ｂ×Ｄの絶対値が大きくなるため、Ａ×Ｃ−Ｂ×Ｄを連続的に評価することによって、２本の指が指示する点間の距離が広がっていっているのか、とどまっているのか、広がっていっているとすればどのような速度で広がっているか、を判断することができる。
従って、ＣＰＵ３５が、後段の装置に情報を出力する際には、数式１によって計算された座標を出力し続けるとともに、Ａ×Ｃ−Ｂ×Ｄもしくはそれを適当に整形した数値を、２本の指が指示する点間の距離の代替値として出力するのが好ましい。
同様に、まず、２本の指で、座標入力領域１８内の、互いに対角方向に離れた２点を指示し（図３（ｃ））、その後、２本の指を、タッチしたまま、互いに近づけていく（図３（ｄ））ような相対運動は、一般的に、縮小を意味するジェスチャとして知られている。
これに対しては、数式１によって計算された座標が時間的にそれほど変化せず、一方で、Ａ×Ｃ−Ｂ×Ｄが、タッチ当初に絶対値が大きく、その後時間の経過とともに小さくなっていくような場合は、この、縮小を意味するジェスチャがなされたと認識することができる。
ただし、縮小を意味するジェスチャについても、２本の指を互いに離す方向を、水平方向もしくは垂直方向とすると、Ａ×Ｃ−Ｂ×Ｄが０となってしまうため、２本の指を互いに離す方向は、斜めにする必要があり、＋４５度もしくは−４５度方向が最も好ましい。
また、数式２を用いて認識できる別のジェスチャとしては、次のようなものがある。例えば、まず、２本の指で、座標入力パネル１１の座標入力領域１８内の、互いに対角方向に離れた２点を指示する（図４（ａ））。その後、タッチしたまま、２本の指が指示する点の相互関係を維持しつつ、２本の指を同じ方向に移動させる（図４（ｂ））。このような相対運動は、例えば、（２本指）スクロール（もしくは（２本指）フリック）を意味するジェスチャとして知られている。
このジェスチャについても、２本の指を互いに離す方向を、水平方向もしくは垂直方向とすると、Ａ×Ｃ−Ｂ×Ｄが０となってしまうため、２本の指を互いに離す方向は、斜めにする必要がある。また、２本の指が指示する点間の距離が小さいと、Ａ×Ｃ−Ｂ×Ｄが０に近く、２本であることを識別できないため、２本の指が指示する点間の距離は大きいほど好ましい。更に、前記したように、Ａ×Ｃ−Ｂ×Ｄは、１本の指で１点を指示している場合でも、長方形の座標入力領域１８の４頂点に近づくほど、０から離れる傾向があるため、数式１によって計算される座標が、座標入力領域１８の４頂点の近傍になるような位置における操作は、タッチしている指が１本であるか２本であるかを識別しにくくなるため、好ましくない。
次に、別の関係式を用いたジェスチャの認識について説明する。２本の指でそれぞれ異なる２点を指示している場合には、限定的な条件下で、次に示す数式３が成立することが分かった。ただし、θは、２本の指で指示している２点を結ぶ直線の、Ｘ軸に対する、Ｘ軸の正方向からＹ軸の正方向に向かう角度（図２では時計回り）である。

The result of the measurement is A (= A ₁ + A ₂ ) (and B, C, D), and individual A ₁ and A ₂ are ignorant. Therefore, (X ₁ , Y ₁ ) and (X ₂ , Y ₂ ) cannot be obtained. However, Formula 2 indicates that if A × C−B × D is not 0, it may be determined that a plurality of fingers are touching. In addition, since A × C−B × D includes (X ₁ −X ₂ ) × (Y ₁ −Y ₂ ), when two different points are indicated by two fingers, the distance between the two points The farther the distance is, the more away from 0. However, since the shape is (X ₁ −X ₂ ) × (Y ₁ −Y ₂ ), even if two different points are indicated by two fingers, a straight line connecting the two points is an XY coordinate system. Note that if it is horizontal or vertical, Equation 2 becomes 0, and it is impossible to identify that two fingers are touching.
In addition, when there are three or more fingers touching, the condition that A × C−B × D becomes 0 increases, and the positional relationship of a plurality of fingers can be determined from the numerical value of A × C−B × D. In this application, the number of touching fingers is limited to one or two because it becomes difficult to read.
Examples of gestures that can be recognized using Equation 2 are as follows. For example, first, with two fingers, substantially the same point in the coordinate input area 18 of the coordinate input panel 11 is indicated (FIG. 3A, the fingertip touches the coordinate input panel 11). Thereafter, the two fingers are kept away from each other toward the diagonal direction in the coordinate input area 18 while being touched (FIG. 3B). Such relative motion is generally known as a gesture that means enlargement.
At this time, the coordinates calculated by Equation 1 are on a straight line connecting the two points designated by two fingers. If a user, for example, uses two index fingers on both hands and touches two points with the same strength and releases them at the same speed, the two fingers touch and leave In the meantime, the coordinates calculated by Equation 1 continue to indicate an intermediate point that bisects the straight line connecting the two points designated by two fingers. On the other hand, the absolute value of A × C−B × D gradually increases from 0 as the distance between the points indicated by the two fingers increases.
From these facts, when the coordinates calculated by Equation 1 do not change so much in time, and A × C−B × D increases with time, it generally means enlargement. It can be recognized that a gesture has been made. A × C−B × D is positive if the positional relationship between the two points indicated by the two fingers in the XY coordinate system of FIG. Therefore, two types of enlargement gestures can be identified.
However, if the direction in which the two fingers are separated from each other is the horizontal direction or the vertical direction, as described above, A × C−B × D is 0 even when the two fingers indicate different points. Therefore, it cannot be identified that the user is touching with two fingers. For this reason, the direction in which the two fingers are separated from each other needs to be oblique, and is in the form of (X ₁ −X ₂ ) × (Y ₁ −Y ₂ ). The 45 degree direction is most preferable.
In addition, when one point is indicated with one finger, A × C−B × D should theoretically always be zero. However, when A × C−B × D is actually calculated using the measured values, A × C−B × D is more distant from 0 as the four vertices of the rectangular coordinate input area 18 are approached. It turns out that there is a tendency. Therefore, regarding the gesture, the operation at the position where the coordinates calculated by Equation 1 are in the vicinity of the four vertices of the coordinate input area 18 is one finger or two fingers touching. Is difficult to identify.
For this reason, it is particularly preferable that the coordinates calculated by Equation 1 be near the center of the coordinate input area 18 for the enlargement gesture. In other words, as a detectable enlargement gesture, two fingers are used to first indicate substantially the same point in the coordinate input area 18 excluding at least the vicinity of the resistive surrounding electrode 13, and then the two fingers. Is widened so that the slope of the straight line connecting the points indicated by each point is not at least horizontal and vertical, and is most preferably a slope close to +45 degrees or −45 degrees.
With respect to this gesture, since two fingers indicate substantially the same point at the start of the gesture, it cannot be identified that two fingers are touching instead of one. It can be recognized that the two fingers indicate different points only after the points indicated by the two fingers are separated to some extent. Further, since the absolute value of A × C−B × D increases as the distance between the points indicated by the two fingers increases, A × C−B × D is continuously evaluated. Thus, it can be determined whether the distance between the points indicated by the two fingers is widened, whether it is staying, or at what speed if it is widened.
Therefore, when the CPU 35 outputs information to the subsequent apparatus, the CPU 35 continues to output the coordinates calculated by the equation 1, and sets A × C−B × D or a numerical value obtained by appropriately shaping the two values. It is preferable to output as an alternative value of the distance between points indicated by the finger.
Similarly, first, two fingers are used to indicate two points in the coordinate input area 18 that are diagonally separated from each other (FIG. 3C), and then the two fingers are kept touched. Relative motion that moves closer to each other (FIG. 3D) is generally known as a gesture that means reduction.
On the other hand, the coordinates calculated by Equation 1 do not change so much in time, while A × C−B × D has a large absolute value at the beginning of the touch and then decreases with time. In any case, it can be recognized that a gesture meaning reduction has been made.
However, for a gesture that means reduction, if the direction in which the two fingers are separated from each other is the horizontal direction or the vertical direction, A × C−B × D becomes 0, so the two fingers are separated from each other. The direction needs to be oblique, and the +45 degree or -45 degree direction is most preferable.
Further, another gesture that can be recognized using Equation 2 is as follows. For example, first, with two fingers, two points in the coordinate input area 18 of the coordinate input panel 11 that are separated from each other are indicated (FIG. 4A). Thereafter, the two fingers are moved in the same direction while maintaining the mutual relationship between the points designated by the two fingers while being touched (FIG. 4B). Such a relative motion is known as a gesture meaning, for example, (two fingers) scrolling (or (two fingers) flick).
Also in this gesture, if the direction in which the two fingers are separated from each other is the horizontal direction or the vertical direction, A × C−B × D is 0. Therefore, the direction in which the two fingers are separated from each other is oblique. There is a need to. Also, if the distance between points designated by two fingers is small, A × C−B × D is close to 0 and cannot be identified as two, so the distance between points designated by two fingers Is more preferable as it is larger. Further, as described above, A × C−B × D tends to move away from 0 as it approaches the four vertices of the rectangular coordinate input area 18 even when one point is designated by one finger. Therefore, an operation at a position where the coordinates calculated by Equation 1 are in the vicinity of the four vertices of the coordinate input area 18 is difficult to identify whether the number of touching fingers is one or two. Therefore, it is not preferable.
Next, gesture recognition using another relational expression will be described. When two different points are indicated by two fingers, it has been found that the following Expression 3 holds under limited conditions. Here, θ is an angle (clockwise in FIG. 2) of a straight line connecting two points designated by two fingers with respect to the X axis from the positive direction of the X axis to the positive direction of the Y axis.

数式３の逆正接関数の引数の分母には、（ａ^２−ｂ^２）という表式が存在する。これは、座標入力領域１８の横と縦の長さが等しい場合、数式３の計算結果が常に＋４５度もしくは−４５度になってしまい、角度を検出できなくなる、ということを示している。抵抗性周囲電極１３の上下辺の長さ及び左右辺の長さ（これらは、座標入力領域１８の横の長さ、及び縦の長さに対応する）、及び、上下辺の長さ当たりの抵抗値と左右辺の長さ当たりの抵抗値の関係を調整することにより、計算に用いるａ及びｂについて、それらが等しくならないようにすることができる。例えば、抵抗性周囲電極１３の上下辺の長さ及び左右辺の長さが等しくなければ、抵抗性周囲電極１３の上下辺の長さ当たりの抵抗値と左右辺の長さ当たりの抵抗値を等しくすることにより、ａとｂが等しくならないようにできる。
数式３を用いて角度を計算する際、逆正接関数の引数の分母と分子を独立して評価することにより、逆正接関数の出力を、［−１８０，＋１８０］度の間で求めることができる。数式３には、逆正接関数に１／２がついているので、結果として、求められる角度θは、［−９０、＋９０］度の範囲になる。２本の指で指示している２点を結ぶ直線に、どちらが始点でどちらが終点か、という区別がないため、２点を結ぶ直線の角度は、常に［−９０、＋９０］度の範囲になる。
数式３によって求められる情報を用いて、一般的に回転を意味するジェスチャを認識することができる。例えば、まず、２本の指で、座標入力パネル１１の座標入力領域１８内の、第１象限の右上部と、第２象限の左下部とを指示する（図５（ａ））。その後、２本の指を、タッチしたまま、第１象限内を指示した指は下方向へ、第２象限内を指示した指は上方向へ、それぞれ動かしていく（図５（ｂ））。このとき、数式１を用いて、２本の指で指示した点の略中間点を求めることができ、Ａ×Ｃ−Ｂ×Ｄを用いて、開始時に、２本の指でタッチしていることを識別することができ、数式３を用いて、２本の指で指示している点を結ぶ直線の傾きを求めることができる。
ただし、数式３を用いて角度を計算するにあたって、ジェスチャの開始時に、２本の指で最初に指示する２点の位置関係は、それぞれが第１象限と第３象限、もしくは第２象限と第４象限にあるような位置関係であってはならない。２点は、同じ象限内にあるか、互いに隣り合った象限内にある必要がある。また、開始時の２点の位置関係が水平もしくは垂直であると、２本の指でタッチしていることを識別できないので、斜めである必要がある。加えて、ジェスチャの終了時、それぞれの指は、最初に指示した象限から別の象限に移動させてはならない。
ＣＰＵ３５は、後段の装置に情報を出力する際には、数式１によって計算された座標を出力し続けるとともに、Ａ×Ｃ−Ｂ×Ｄもしくはそれを適当に整形した数値を、２本の指が指示する点間の距離の代替値として出力し、更に、数式３によって計算した数値をも出力するのが好ましい。もしくは、Ａ、Ｂ、Ｃ、Ｄといった測定値を後段の装置に出力し、数式３を用いた計算などを、後段の装置において実行しても構わない。

In the denominator of the argument of the arc tangent function of Equation 3, there is an expression (a ² −b ² ). This indicates that when the horizontal and vertical lengths of the coordinate input area 18 are equal, the calculation result of Equation 3 is always +45 degrees or −45 degrees, and the angle cannot be detected. The lengths of the upper and lower sides and the left and right sides of the resistive surrounding electrode 13 (which correspond to the horizontal length and the vertical length of the coordinate input area 18) and the length of the upper and lower sides By adjusting the relationship between the resistance value and the resistance value per left and right side length, a and b used in the calculation can be made not equal. For example, if the length of the upper and lower sides of the resistive surrounding electrode 13 and the length of the left and right sides are not equal, the resistance value per length of the upper and lower sides of the resistive surrounding electrode 13 and the resistance value per length of the left and right sides are calculated. By making them equal, a and b can be prevented from being equal.
When calculating the angle using Equation 3, the output of the arc tangent function can be obtained between [−180, +180] degrees by independently evaluating the denominator and numerator of the arc tangent function argument. . In Equation 3, since the arc tangent function is 1/2, as a result, the obtained angle θ is in the range of [−90, +90] degrees. Since there is no distinction as to which line is the starting point and which is the ending point in the line connecting the two points designated by two fingers, the angle of the line connecting the two points is always in the range of [−90, +90] degrees. .
Using information obtained from Equation 3, it is possible to recognize a gesture that generally means rotation. For example, first, with two fingers, the upper right part of the first quadrant and the lower left part of the second quadrant in the coordinate input area 18 of the coordinate input panel 11 are indicated (FIG. 5A). Thereafter, with the two fingers touching, the finger pointing in the first quadrant moves downward, and the finger pointing in the second quadrant moves upward (FIG. 5B). At this time, it is possible to obtain a substantially intermediate point between the points designated by two fingers using Formula 1, and touch with two fingers at the start using A × C−B × D. This can be identified, and the slope of the straight line connecting the points designated by two fingers can be obtained using Equation 3.
However, when calculating the angle using Equation 3, at the start of the gesture, the positional relationship between the two points first designated with two fingers is the first quadrant and the third quadrant, or the second quadrant and the second quadrant. The positional relationship should not be in the four quadrants. The two points need to be in the same quadrant or in quadrants adjacent to each other. In addition, if the positional relationship between the two points at the start is horizontal or vertical, it cannot be identified that the two fingers are touching, and therefore it needs to be diagonal. In addition, at the end of the gesture, each finger must not be moved from the first instructed quadrant to another quadrant.
When the CPU 35 outputs information to the subsequent device, the CPU 35 continues to output the coordinates calculated according to Equation 1, and the two fingers can set A × C−B × D or a numerical value obtained by appropriately shaping the coordinates. It is preferable to output as a substitute value of the distance between the points to be pointed, and also to output the numerical value calculated by Equation 3. Alternatively, the measurement values such as A, B, C, and D may be output to the subsequent apparatus, and the calculation using Equation 3 may be executed in the subsequent apparatus.

Hereinafter, the present invention will be described by way of examples. The present invention is not limited to the following examples, and includes various modifications within the technical scope of the present invention.
Example 1
The coordinate input panel 11 was created as follows. As a glass substrate, soda glass (thickness 3 mm) cut into a size of about 469 × 375 mm is used, and an ITO (indium oxide) film is formed on the surface of the glass substrate by sputtering. A resistor 12 was obtained. Next, the resistive surrounding electrode 13 and part of the lead wires 22 to 25 are screen-printed with heat-cured paste obtained by mixing carbon in silver paste LS-504 (resin binder) manufactured by Asahi Chemical Research Co., Ltd. It was formed by letting. At this time, the shape of the coordinate input area 18 was a rectangle of 2a = 378 mm and 2b = 303 mm. The width of the resistive surrounding electrode 13 is adjusted so that the resistance value between the vertices AB of the resistive surrounding electrode 13 is about 68Ω and the resistance value between the vertices BC is about 52Ω, and 378/303 = 1.25≈68 / By setting 52 = 1.31, the resistance values per length of all sides of the resistive surrounding electrode 13 were made substantially equal. The lead wires 22 to 25 are each divided into a printed portion and a low-resistance lead wire portion on the glass, and the printed portion is located outside the resistive surrounding electrode 13 at the center of the left side of the coordinate input panel. In order to connect to the low resistance lead wires of the lead wires 22 to 25, all are configured in a pattern such that all have the shortest distances, and the width of the printed portion has a resistance value per side of the resistive surrounding electrode. Adjustment was made so that the resistance value on one side was about 1/2 to 1/4. In FIG. 6, the schematic diagram of the coordinate input panel 11 including the printed part of the leader lines 22-25 is shown. Next, joints 36 to 39 were formed using silver paste at the joints between the lead wires 22 to 25 and the lead wires in the center of the left side of the coordinate input panel.
Further, a transparent insulating base material was formed on the surface resistor 12. In order to form a transparent insulating substrate, a glass paste was printed on the surface resistor 12 and the resistive surrounding electrode 13, heat treated to melt the powdered glass, and sintered. Finally, the lead wires 22 to 25 were connected to the joint portions 36 to 39 by soldering. At this time, the sheet resistance of the surface resistor 12 was set to 500Ω / □.
The coordinate input panel 11 created in this way was connected to the hardware created as shown in the block diagram of FIG. In addition, coordinate data and measurement values such as A, B, C, and D are output from the CPU 35, and these are taken into a personal computer by serial communication so that calculations other than coordinates are performed by the personal computer. The orthogonal coordinate system XY was set as shown in FIG. In addition, instead of A × C−B × D, it is normalized as (A × C−B × D) / ((A + C) × ( B + D)) was used.
Using this coordinate input system, the above numerical values were evaluated for the enlargement and reduction gestures as shown in FIGS. 3A to 3D, and the results shown in the graph of FIG. 7 were obtained. . The horizontal axis indicates time, the left vertical axis indicates the coordinates (X, Y) calculated by Equation 1, and the right vertical axis indicates (A × C−B × D) / ((A + C) × (B + D). )). The four schematic diagrams arranged at the bottom of the graph correspond to the positions on the horizontal axis where the respective schematic diagrams are arranged, and first, the two fingers are used to approximately center the coordinate input area 18 of the coordinate input panel 11. Then, with the two fingers touching, they are separated from each other toward the diagonal direction (upper left and lower right) in the coordinate input area 18, and the pair of the coordinate input area 18 is paired with the two fingers. This indicates that the corners have been instructed for a while, and finally, while being touched, they approached each other toward the substantially central portion of the coordinate input area 18.
At this time, the coordinate (X, Y) continues to indicate a substantially intermediate point (near (0, 0)) of each different point designated by two fingers, while (A × C−B × D) / (( A + C) × (B + D)) increases as the points indicated by the two fingers move away from each other, and then gradually decreases as the points approach.
Therefore, it was confirmed that the coordinate input system indicates two different points with two fingers, and that the relative movement of the two fingers in the diagonal direction of the panel can be detected.
(Example 2)
Using the coordinate input system manufactured in Example 1, the coordinates (X, Y) calculated by Equation 1 for the two-finger scroll gesture as shown in FIGS. 4 (a) and 4 (b), and When (A × C−B × D) / ((A + C) × (B + D)) was evaluated, the results shown in FIG. 8 were obtained.
FIG. 8A is a plot of the coordinates calculated by Equation 1 in the XY plane. When the two fingers are moved from left to right, the Y coordinate maintains the approximate center of the panel in the vertical direction. This indicates that the coordinates calculated by Equation 1 are approximately halfway between the two points indicated by two fingers. On the other hand, FIG. 8B is a plot of (A × C−B × D) / ((A + C) × (B + D)) at that time, and the horizontal axis indicates time. When two fingers are moved from left to right, the numerical value is maintained at about -0.1. A negative numerical value indicates that the positional relationship between the two points designated by two fingers is rising to the right.
When one finger designates approximately 1/4 of the panel width from the left end of the coordinate input area 18 and approximately the center of the panel in the vertical direction and moves it from left to right, the coordinates are as shown in FIG. Although it moves similar to (a), (A × C−B × D) / ((A + C) × (B + D)) is only about plus or minus 0.01.
Therefore, it is confirmed that the coordinate input system can detect the movement performed while maintaining the relative relationship of the two fingers when the two fingers indicate two different points that are diagonally separated from each other. It was done.
(Example 3)
Using the coordinate input system manufactured in the first embodiment, the coordinates (X, Y), (A × C) calculated by Equation 1 are used for the rotation gesture as shown in FIGS. 5 (a) and 5 (b). When the angle calculated by −B × D) / ((A + C) × (B + D)) and Equation 3 was evaluated, the results shown in FIG. 9 were obtained.
In FIG. 9A, the horizontal axis represents time, the left vertical axis represents the coordinates (X, Y) calculated by Equation 1, and the right vertical axis represents (A × C−B × D) / ( (A + C) × (B + D)). The two schematic diagrams arranged at the bottom of the graph correspond to the positions on the horizontal axis where the respective schematic diagrams are arranged. First, with the two fingers, the upper right part of the first quadrant in the coordinate input area 18 , Pointing to the lower left of the second quadrant, and then touching the two fingers, the finger pointing in the first quadrant is downward, the finger pointing in the second quadrant is upward, Indicates that they have moved.
FIG. 9B shows the angle calculated by Equation 3 on the same horizontal axis as FIG. 9A.
At this time, the coordinates (X, Y) continue to indicate a substantially intermediate point between different points designated by two fingers, that is, the X coordinate is almost 0 and the Y coordinate is a value away from 0 without much change. On the other hand, (A × C−B × D) / ((A + C) × (B + D)) is a negative value at the start when the positional relationship between two different points indicated by two fingers is rising to the right. At the end of falling to the right, a positive value was shown. In the middle, when the positional relationship between the two points indicated by the two fingers becomes horizontal, it becomes zero. However, at the start, the absolute value of A × C−B × D) / ((A + C) × (B + D)) is obtained in a state where the coordinates calculated by Equation 1 are not in the vicinity of the four vertices of the coordinate input area 18. Since it is about 0.2, it can be identified that there are two touching fingers at the start.
Further, as shown in FIG. 9B, the angle of the straight line connecting two different points indicated by the two fingers respectively calculated by Expression 3 is about −30 degrees at the start and about +40 degrees at the end. In the meantime, it shows a smooth change.
Therefore, it was confirmed that the coordinate input system can detect the rotation-like relative motion performed by the two fingers when the two fingers indicate two different points that are diagonally separated from each other. .

DESCRIPTION OF SYMBOLS 1 Coordinate input panel 2 Surface resistor 3 Resistive surrounding electrode 4, 5, 6, 7 Detection electrode 8 Coordinate input area 11 Coordinate input panel 12 Surface resistor 13 Resistive surrounding electrode 14, 15, 16, 17 Detection electrode 18 Coordinate Input area 21 Fingers 22, 23, 24, 25 Lead lines 26, 27, 28, 29 External resistance component 30 Analog signal processing unit 31 Vibration voltage application circuit 32 Vibration voltage generator 33 Analog multiplexer 34 A / D converter 35 CPU
36, 37, 38, 39

Claims (1)

A rectangular coordinate input region that is at least a single connection with a surface resistor formed thereon, and provided on the four sides constituting the outer edge of the rectangular coordinate input region so as to be in electrical contact with the surface resistor. A linear resistive peripheral electrode having a constant resistance value per unit length and at least equal resistance values per unit length between opposing sides, and the resistance at four vertices of the rectangular coordinate input region A detection electrode provided in electrical contact with the sexual surrounding electrode, a current measuring means for measuring a current flowing through the four detection electrodes, and a position in the coordinate input area when indicated by a finger, The coordinate calculation means for calculating the position in the coordinate input area indicated by the finger from the current values flowing in the four detection electrodes, and the coordinate input area 1 in the coordinate input area from the current values flowing in the four detection electrodes. Point one point with a finger If it is identified that two different points are indicated by two fingers, and if two points are indicated by two fingers, the relative movement performed by the two fingers is determined. A coordinate input system comprising an identification recognition means for recognizing.

Images