JP2004335273A - Touch sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a touch sensor capable of detecting whether a finger is moving on an operation panel or not and detecting a direction of movement, moving speed, and a position of the finger or the like with a simple construction. <P>SOLUTION: Since a distance d between the finger H and an opposing electrode 23 differs according to the position of the finger H on the operation panel 24, a static capacity C between the finger and the electrode can be changed in compliance with the position of the finger H. Accordingly, the position of the finger on the operation panel 24 can be detected by detecting a voltage corresponding to the static capacity C by a C/V conversion means. Further, as the voltage decreases according to the movement of the finger in an X2 direction, and increases according to the movement in an X1 direction, existence of the movement, and the moving speed as well can be detected. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a touch sensor capable of detecting, for example, a capacitance between a human finger and a touch sensor, and particularly relates to a touch sensor capable of detecting presence / absence of a finger movement and a moving direction thereof with a simple configuration.
[0002]
[Prior art]
As a prior art document in the same technical field as the present invention, for example, there is one disclosed in Patent Document 1.
[0003]
In the capacitance type sensor described in the above-mentioned technical document 1, in the case of the first embodiment, in particular, the detection unit and the C / V converter detect a change in the stray capacitance C generated around the electrode according to the degree to which the finger approaches the electrode. Is converted into a voltage.
[0004]
In the second embodiment and the like, a plate-like member elastically deformable is provided in parallel with the electrode, and a change in the stray capacitance C generated around the electrode is detected based on the degree of pushing of the plate-like member by a finger. And voltage conversion by the C / V converter.
[0005]
Further, in the third and fifth embodiments, a plurality of electrodes are arranged on a substrate, and a difference between stray capacitances generated around the electrodes is converted into a voltage.
[0006]
[Patent Document 1]
JP-A-2000-18905
[0007]
[Problems to be solved by the invention]
However, the above-mentioned conventional capacitance type sensor has the following problems.
(1) The capacitance-type sensor according to the first embodiment can detect that a finger has approached the electrode, but can detect whether the finger is moving or remains at one point on the electrode (movement). Detection of the presence or absence of
(2) In the second embodiment, since the plate-shaped member is elastically deformed by the pressing force of the finger and the distance between the finger and the electrode changes, it is possible to detect a change in the stray capacitance. However, this change in the stray capacitance means the amount of depression, that is, the magnitude of the pressing force of the finger, and does not mean that the presence or absence or the moving direction of the finger can be detected.
(3) In the third and fifth embodiments, the direction in which the operation axis is tilted, that is, the direction in which an external force is applied can be detected by detecting the difference in the stray capacitance between the electrodes. It is impossible to detect the presence or absence of movement and the direction of movement.
[0008]
An object of the present invention is to solve the above-mentioned conventional problems, and an object of the present invention is to provide a touch sensor capable of detecting the presence or absence of a finger movement or the direction of movement thereof with a simple configuration.
[0009]
[Means for Solving the Problems]
The present invention is generated between a counter electrode provided on the fixed portion side, an insulating operation surface arranged to face the counter electrode, and a movable electrode moving along the operation surface and the counter electrode. C / V conversion means for detecting the capacitance C as a voltage V according to the magnitude of the capacitance C.
When the movable electrode moves on an operation surface, at least one or more elements of a facing distance, a facing area, or a dielectric constant between the movable electrode and a facing electrode are changed. .
[0010]
According to the present invention, when the movable electrode moves on the operation surface, at least one element of the facing distance, the facing area, or the dielectric constant is changed to cause a change in the capacitance. Specifically, it is realized by the following simple configuration.
[0011]
For example, one of the counter electrode and the operation surface is a plane, and the other is curved with respect to the plane.
[0012]
Alternatively, the counter electrode and the operation surface are both formed as flat surfaces, and the counter electrode is provided to be inclined with respect to the operation surface.
[0013]
Further, the counter electrode is provided in parallel with the operation surface, and the counter electrode is provided with a slit having a predetermined width.
[0014]
In this case, the width of the conductive portion between the adjacent slits formed in the counter electrode can be configured to be gradually narrowed from one end to the other end. .
[0015]
The counter electrode is provided in parallel with the operation surface, and has a linear dielectric constant between the operation surface and the counter electrode according to a distance from one end to the other end. Alternatively, a dielectric that changes stepwise is provided.
[0016]
Alternatively, between the operation surface and the counter electrode, dielectrics having a predetermined width dimension and different dielectric constants are juxtaposed, and the dielectrics are directed from one end to the other end. Are arranged so that the dielectric constant becomes lower in accordance with the following.
[0017]
In addition, the C / V detection means may include a clock signal generation means for generating a clock signal, and the C / V detection means may include a clock signal according to a capacitance detected by the counter electrode when the movable electrode moves on the operation surface. Delay means for giving rise delay to a signal; smoothing means for generating a signal corresponding to the delay amount given delay with reference to the clock signal not passing through the delay means; and a signal corresponding to the change amount. A / D conversion means for performing A / D conversion can be detected.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
The touch sensor described in each of the following embodiments can be mounted on any electronic device such as a controller such as a computer, a PDA, and a game machine, an AV device, and a robot toy.
[0019]
FIG. 1 is a cross-sectional view showing a first embodiment of the touch sensor of the present invention, FIG. 2 is a circuit configuration diagram showing C / V conversion means for converting the capacitance of the touch sensor into a voltage, and FIG. A shows a signal at each part of the C / V conversion means, where A is a clock signal inputted to one input part of the AND circuit, and B is an output from the signal delay means inputted to the other input part of the AND circuit. A signal C indicates an output signal of the AND circuit, and D indicates an output signal of the smoothing means. The solid line shows the case where the capacitance C is large, and the dotted line shows the case where the capacitance C is small.
[0020]
The touch sensor 1 shown in FIG. 1 has a flat rectangular frame 2 having a long side in the X direction in the drawing on the fixed portion side, and a planar shape extending in the X direction on an inner bottom surface 2 a of the frame 2. The counter electrode 3 is laid. An operation surface 4 made of an insulating sheet or the like is provided between one edge 2b and the other edge 2c in the X direction of the frame 2.
[0021]
The operation surface 4 is formed in a curved shape, and in the first embodiment, is constituted by a part of a cylinder (radius r) having a center in the Z2 direction in the figure. Therefore, the distance between the operation surface 4 and the opposing electrode 3 is set to the shortest opposing distance d1 between the one edge 2b and the other edge 2c, and the distance from the one edge 2b and the other edge 2c is set. The opposing distance extends toward the intermediate point between the two, and is set to the longest opposing distance d2 at the intermediate point.
[0022]
In addition, an air space may be provided between the opposing electrode 3 and the operation unit, or a dielectric having a predetermined dielectric constant may be provided.
[0023]
As shown in FIG. 1, when a human body (movable electrode) H such as a finger is brought into contact with the operation surface 4 in a state where a voltage is applied to the counter electrode 3 of the touch sensor 1, the human body H and the counter electrode 3 And a capacitance C is formed between them. At this time, if the opposing distance between the opposing electrode 3 and the human body H is d, the opposing area is S, and the dielectric constant is ε, the capacitance C between the opposing electrode 3 and the human body H is C = ε・ S / d.
[0024]
When the human body H is moved along the surface of the operation surface 4 in the X direction in the figure, the capacitance C is equal to that of the human body H, if the facing area S and the dielectric constant ε are considered to be constant. H depends on the facing distance d. That is, C1 = ε · S / d1 at both ends in the X direction of the frame 2 and C2 = ε · S / d2 at the intermediate point. Since d2> d1, the capacitance C is related to C1> C2. become. That is, in the touch sensor 1, the capacitance C is set so that the capacitance C decreases as the human body H moves from both ends of the frame 2 toward the intermediate point. Therefore, the human body H functions as a movable electrode that forms a capacitance C with the counter electrode 3.
[0025]
Note that the operation surface 4 may be formed in a plane, and the counter electrode 3 may be formed in a curved shape.
[0026]
As shown in FIG. 2, the capacitance C constitutes a part of the C / V conversion means 10. The C / V conversion unit 10 includes a clock signal generation unit 11, a signal delay unit 12, a delay amount detection unit 13, an A / D conversion unit 14, and a control unit 15. In this embodiment,
The clock signal generator 11 continuously outputs a regular pulse signal having a predetermined frequency. The signal delay means 12 includes a resistance R (constant) connected between the capacitance C and the clock signal generation means 11. The delay amount detecting means 13 is composed of an AND circuit 13A and a smoothing means 13B provided at a subsequent stage and composed of a resistor Ra and a capacitor Ca. Input signals 13a and 13b of the AND circuit 13A receive a signal passed through the signal delay unit 12 and a clock signal CK (a clock signal not passed through the signal delay unit 12) output from the clock signal generation unit 11. The output of the AND circuit 13A is input to the smoothing means 13B.
[0027]
At the subsequent stage of the smoothing means 13B of the delay amount detecting means 13, for example, an 8-bit A / D converting means 14 is connected. Each of the A / D conversion means 14 converts the output voltage (analog amount) of the smoothing means 13B into digital outputs D0 to D7 at a predetermined sampling cycle and outputs the digital outputs D0 to D7. The control unit 15 is mainly configured by a CPU, and monitors data of digital outputs D0 to D7 output from each A / D conversion unit 14.
[0028]
In the state where the clock signal CK having a predetermined frequency of the amplitude voltage Vcc as shown in FIG. 3A is being output from the clock signal generation means 11 to the AND circuit 13A and the signal delay means 12, the operation signal is brought into contact with the operation surface 4. When the human body H is moved in the X direction, the facing distance d changes as described above, so that the capacitance C changes.
[0029]
In other words, when the human body H is located at both ends in the X direction, the time constant C1 · multiplied by the product of the resistance R of the signal delay means 12 and the capacitance C1 (C1 = ε · S / d1) therebetween. Since R becomes large, the output of the signal delay means 12 becomes a triangular signal Sa as shown by a solid line in FIG. 3B. Therefore, the output (logical product) of the AND circuit 13A has a pulse waveform with a pulse width ta as shown by a solid line in FIG. 3C. Here, the threshold SL of the H level and the L level in the AND circuit 13A is set to Vcc / 2.
[0030]
On the other hand, when the human body H is moved to an intermediate point on the operation surface 4, a time constant C2 defined by the product of the resistance R of the signal delay means 12 and the capacitance C2 (C2 = ε · S / d2) therebetween. Since R becomes small, the output of the signal delay means 12 has a waveform Sb as shown by a chain line in FIG. 3B. Therefore, the output (logical product) of the AND circuit 13A has a pulse waveform with a pulse width tb, as shown by the dashed line in FIG. 3C.
[0031]
Here, the pulse width ta when the capacitance C is small and the pulse width tb when the capacitance C is large have a relationship of ta <tb. Therefore, the output voltage of the smoothing means 13B is such that the output voltage Vb when the human body H is moved to the intermediate point on the operation surface 4 (when the capacitance C is small) is moved to both ends ( It is output as a value (Va <Vb) larger than the output voltage Va when the capacitance C is large.
[0032]
The output voltages Va and Vb of the smoothing unit 13B are converted into digital outputs D0 to D7 by the A / D conversion unit 14 and sent to the control unit 15.
[0033]
Since the output of the smoothing means 13B changes with time according to the movement of the human body H, the digital outputs D0 to D7 of the A / D conversion means 14 are also changed accordingly.
[0034]
Therefore, the control unit 15 periodically monitors the digital outputs D0 to D7 of the A / D conversion means 14, that is, determines whether or not the magnitude of the capacitance C changes with time. 4, it is possible to detect whether or not the human body H is moving.
[0035]
When the human body H is moved from both ends of the frame 2 toward the intermediate point, the capacitance C gradually decreases, and when the human body H is moved from the center point toward both ends of the frame 2. The magnitude of the capacitance C gradually increases. Therefore, depending on whether the magnitude of the capacitance C is decreasing or increasing, the control unit 15 moves the human body H from the end of the frame 2 toward the center point. It is also possible to detect whether it is moving in the direction from the center to the ends.
[0036]
However, in the first embodiment, it is unknown whether the human body H is moving in the X1 direction or in the X2 direction. Therefore, a touch sensor capable of detecting the moving direction and position of the human body H will be described.
[0037]
FIG. 4 is a sectional view showing a second embodiment of the touch sensor of the present invention. The C / V conversion means for converting the capacitance into a voltage is the same as the configuration shown in FIG.
[0038]
In the touch sensor 21 according to the second embodiment shown in FIG. 4, the inner bottom surface of the frame 22 is formed by an inclined surface 22a inclined with respect to the horizontal X axis, and the counter electrode 23 is formed on the inclined surface 22a. It is laid at an angle. An operation surface 24 made of an insulating sheet or the like is provided on the edges 22b and 22c of the frame 22 in parallel with the X axis.
[0039]
The opposing distance d between the operation surface 24 and the opposing electrode 23 is set to the shortest opposing distance d1 at the end of the illustrated X1, and the opposing distance d gradually increases in proportion to the direction toward the illustrated X2. Is set to the longest facing distance d2 at the end of. Therefore, when the human body H is moved on the operation surface 4 in a state of contact, the capacitance C is the largest at the end on the X1 side, gradually decreases toward the X2 direction, and becomes the smallest at the end on the X2 side. It shows a small value.
[0040]
Therefore, by periodically detecting the change in the capacitance C using the C / V conversion means 10, it is possible to detect the presence or absence of the movement of the human body H, the direction, position, and speed of the movement.
[0041]
That is, when the digital outputs D0 to D7 of the A / D conversion means indicate a decrease in the voltage, it can be detected that the human body H is moving in the illustrated X2 direction, which is the direction in which the facing distance d extends. When the digital outputs D0 to D7 indicate an increase in the voltage, it can be detected that the human body H is moving in the X1 direction shown in the drawing, in which the facing distance d decreases.
[0042]
The magnitude of the capacitance C changes in inverse proportion to the facing distance d, assuming that the permittivity ε and the facing area S are constant. Therefore, the position in the X direction can be detected from the magnitude of the capacitance C. Further, the moving distance can be obtained from the position, and the moving speed can be detected by differentiating the moving distance with time.
[0043]
FIGS. 5 to 7 show third and fourth embodiments of the touch sensor of the present invention. FIG. 5 shows a cross-sectional view of a touch sensor, which is common to the third and fourth embodiments. 6 is a plan view of a counter electrode according to a third embodiment, FIG. 7A is a plan view of a counter electrode according to a fourth embodiment, and FIGS. 7B and 7C are modifications of the fourth embodiment. FIG. 8 is a plan view of a counter electrode showing an example, and FIG. 8 is a plan view of a counter electrode showing a fifth embodiment. The C / V conversion means for converting the capacitance into a voltage is the same as the configuration shown in FIG.
[0044]
As shown in FIG. 5, in the touch sensor 31 according to the third and fourth embodiments, the operation surface 34 made of an insulating sheet is provided on the edges 32b and 32c of the frame 32 in parallel with the X axis. It is the same as the second embodiment in that it is provided. However, the inner bottom surface 32a of the frame 32 is formed as a plane parallel to the operation surface 34, and the bottom surface 32a is provided with one of the counter electrodes shown in FIGS. 6, 7A to 7C. ing.
[0045]
In the third embodiment, a counter electrode 33 shown in FIG. 6 is provided on the bottom surface 32a of the frame 32. The opposing electrode 33 has a plurality of slits 33a cut out in a rectangular shape with a width dimension Ws on the conductive plate at a pitch Pa equal to the X direction.
[0046]
As shown in FIG. 6, when a finger or the like that is a part of the human body H is brought into contact with the operation surface 34, the hatched portion where the conductive portion 33b of the counter electrode 33 except for the slit 33a and the human body H face each other has an opposing area S. Assuming that the dielectric constant between the counter electrode 33 and the human body H is ε, a capacitance C of C = ε · S / d is formed between the two.
[0047]
Then, when the human body H is moved in the X direction, the capacitance C can be changed. That is, when the human body H is opposed to the counter electrode 33, the state of the region facing the human body H includes a state in which more slits 33a are included and a state in which the counter electrode 33 between the slits 33a is larger. When the human body H is moved in the X direction, a state in which more slits 33a are included and a state in which more counter electrodes 33 are included are alternately repeated. Become. Therefore, the opposing area S changes due to the movement of the human body H in the X direction, so that the capacitance C defined by C = ε · S / d can be changed periodically. Therefore, if the C / V converter 10 detects the periodic fluctuation of the capacitance C, the control unit 15 can detect that the human body H is moving in the X direction. Since the cycle of the change in the capacitance C occurs in accordance with the moving distance of the human body H, the moving speed of the human body H can be detected by calculating the time required for one cycle.
[0048]
However, in the third embodiment, it is difficult to detect the moving direction. Therefore, a configuration in which the moving direction can be detected will be described in the fourth to sixth embodiments.
[0049]
In the fourth embodiment shown in FIG. 7A, the widths Ws of the slits 43a formed in the opposing electrode 43 are all the same, but the width of the conductive portion 43b between the adjacent slits 43a. Wb is the widest Wb1 on the X1 side in the drawing, gradually narrows in the X2 direction, and is formed with the narrowest Wb6 on the X1 side in the drawing (Wb1>Wb2>...> Wb6). The other configuration is the same as that of the third embodiment.
[0050]
Also in the fourth embodiment, when the human body H is moved in the X direction, the facing area S can be changed, so that the capacitance C can be changed according to the movement of the human body H. In other words, when moved in the X2 direction from the illustrated X1 side, the opposing area S gradually decreases, so that the capacitance C defined by C = ε · S / d also gradually decreases. Therefore, the voltage detected from the C / V conversion means 10 can also be changed in a direction to gradually decrease. In addition, when moving from the X2 side in the figure to the X1 direction, the facing area S gradually increases, so that the capacitance C also gradually increases. Therefore, the voltage detected from the C / V conversion means 10 can be changed in a gradually increasing direction.
[0051]
Therefore, when the voltage detected from the C / V conversion means 10 gradually decreases, the control unit 15 can detect that the human body H is moving from the X1 side to the X2 side, When the voltage gradually increases, it is possible to detect that the voltage is moving in the opposite direction.
[0052]
7B and 7C show a modification of the fourth embodiment shown in FIG. 7A. The counter electrode 53 shown in FIG. 7B is formed by alternately cutting (cutting) a part of the electrode connecting the slit 53a and the slit 53a. The counter electrode 63 shown in FIG. 7C has a slit 63a and a slit 63a. Are formed by cutting (cutting) one edge in the Y direction (the edge in the Y2 direction in FIG. 7C) of the electrode connecting the electrodes, and the other configuration is the same as that of the counter electrode 43 in FIG. 7A. .
[0053]
In the fourth embodiment, the moving direction of the human body H can be detected by forming the slits 53a or 63a as described above, similarly to FIG. 7A.
[0054]
In the fifth embodiment shown in FIG. 8, the counter electrode 63 of FIG. 7C shown as a modification of the fourth embodiment is further modified to a circular shape. In this embodiment, all the slits 93a of the counter electrode 93 are formed at the same angle θ. However, the angle φ of the conductive portion 93b between the adjacent slot 93a and the slit 93a is formed so as to gradually increase from the conductive portion 93b1 to the conductive portion 93b6 in the counterclockwise direction in the drawing. That is, assuming that the angles of the conductive portions 93b1, 93b2, ..., 93b6 are φ1, φ2, ..., φ6, respectively, there is a relationship of φ1 <φ2 <... <φ6.
[0055]
In the fifth embodiment, when the human body H is moved clockwise or counterclockwise in a state where the human body H faces the conductive portions 93b1, 93b2,..., 93b6 of the counter electrode 93, the human body H Therefore, the capacitance C can be changed in accordance with the movement of the human body H. That is, when the human body H is moved in the counterclockwise direction in the figure from the conductive portion 93b1 to the conductive portion 93b6, the facing area S gradually increases, and thus the capacitance C defined by C = ε · S / d. Can also be gradually increased in size. Therefore, the voltage detected from the C / V conversion means 10 can also be changed in a direction to gradually increase. Further, when the human body H is moved from the conductive portion 93b6 toward the conductive portion 93b1 in the clockwise direction in the drawing, the facing area S gradually decreases, and the magnitude of the capacitance C also gradually decreases. Therefore, the voltage detected from the C / V conversion means 10 can be changed in a gradually decreasing direction.
[0056]
Therefore, when the voltage detected from the C / V conversion means 10 gradually increases, the control unit 15 can detect that the human body H is moving in the counterclockwise direction, When the voltage gradually decreases, it is possible to detect that the human body H is moving in the clockwise direction.
[0057]
FIG. 9 shows a touch sensor according to a sixth embodiment of the present invention, in which A is a cross-sectional view of the touch sensor, and B is a transition diagram showing the state of the dielectric constant of the ionizer. FIG. 10 shows a touch sensor according to a seventh embodiment of the present invention, wherein A is a cross-sectional view of the touch sensor, and B is a transition diagram showing the state of the dielectric constant of the ionizer.
[0058]
In the touch sensor 71 of the sixth embodiment shown in FIG. 9A, an operation surface 74 made of an insulating sheet is provided on the edges 72b and 72c of the frame 72 in parallel with the X axis. An inner bottom surface 72a of the frame 72 is formed as a plane parallel to the operation surface 34, and a flat counter electrode 73 is laid on the bottom surface 72a.
[0059]
As shown in FIG. 9A, the touch sensor 71 has a dielectric 75 provided between the counter electrode 73 and the operation surface 74. As shown in FIG. 9B, in the dielectric 75, when the dielectric constant of the end on the X1 side in the drawing is ε1 and the dielectric constant of the end on the X2 side in the drawing is ε2, the two have a relationship of ε1 <ε2, And it is formed so that it may change linearly with distance from the end on the X1 side to the end on the X2 side.
[0060]
On the other hand, the touch sensor 81 according to the seventh embodiment shown in FIG. 10A is different from the touch sensor 81 according to the fifth embodiment in that a dielectric 85 is provided between the opposing electrode 83 and the operation surface 84. It has the same configuration as 71. However, in the touch sensor 81, the dielectric constant ε of the dielectric 85 does not change gradually, and a plurality of dielectrics (11 types in FIG. 10) having different dielectric constants ε are arranged in parallel with a predetermined width. Is different. The relationship between adjacent dielectrics 85 in the touch sensor 81 is such that the right dielectric in the figure is lower than the dielectric constant ε of the left dielectric. That is, assuming that the dielectric constants of the dielectrics 85a, 85b, 85c,..., Dielectric 85k are εa, εb, εc,. As shown in FIG. 10B, the dielectric constant changes stepwise (stepwise) from εa to εk.
[0061]
In the sixth embodiment, the facing area S and the facing distance d are constant, and when the human body H is moved in the X direction, the permittivity ε can be changed according to the position in the X direction. When the human body H is moved from the X1 side in the figure to the X2 direction, the dielectric constant ε gradually decreases, so that the capacitance C defined by C = ε · S / d also gradually decreases. Therefore, the voltage detected from the C / V converter 10 also gradually decreases. Further, when the substrate is moved from the X2 side in the figure to the X1 direction, the dielectric constant ε gradually increases, so that the magnitude of the capacitance C also gradually increases. That is, the output of the C / V converter 10 can be a voltage corresponding to the position in the X direction.
[0062]
Therefore, when the voltage detected from the C / V conversion means 10 gradually decreases, the control unit 15 can detect that the human body H is moving from the X1 side to the X2 side. When the voltage changes to a gradually increasing direction, it can be detected that the voltage is moving in the opposite direction.
[0063]
In the seventh embodiment, when the human body H is moved in the X direction, the capacitance C can be changed for each predetermined distance (for each step) defined by the width of the dielectric 85. Therefore, similarly to the case of the sixth embodiment, the control unit 15 can detect the moving direction of the human body H depending on whether the voltage detected by the C / V conversion unit 10 is decreasing or increasing.
[0064]
In the touch sensors of the sixth and seventh embodiments, it is also possible to detect the position of the human body on the operation surface.
[0065]
In the touch sensors described in the third to seventh embodiments, as shown in the first and second embodiments, the counter electrode and the operation surface need to be formed in a curved shape or be inclined. Therefore, the thickness of the touch sensor can be reduced.
[0066]
Further, in the above-described embodiment, the touch sensor in which only one of the facing distance d, the facing area S, and the permittivity ε is changed has been described. However, the touch sensor that changes by combining the two or more elements is described. May be used.
[0067]
The movable electrode is not limited to a human body, but may be an input pen or the like.
[0068]
【The invention's effect】
As described above, in the present invention, at least one element of the facing distance, the facing area, or the dielectric constant that forms the capacitance can be changed with a simple configuration, so that the human body is moved along the operation surface. In this case, it is possible to provide a touch sensor capable of detecting whether or not the human body has moved, a moving direction, a moving speed, a position, and the like.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a first embodiment of a touch sensor according to the present invention;
FIG. 2 is a circuit diagram showing C / V conversion means for converting the capacitance of the touch sensor into a voltage,
FIG. 3 shows signals at various parts of the C / V conversion means, where A is a clock signal input to one input part of the AND circuit, and B is a signal delay means input to the other input part of the AND circuit. , C is the output signal of the AND circuit, D is the output signal of the smoothing means,
FIG. 4 is a sectional view showing a touch sensor according to a second embodiment of the present invention;
FIG. 5 is a cross-sectional view showing third and fourth embodiments of the touch sensor of the present invention;
FIG. 6 is a plan view of a counter electrode according to a third embodiment,
FIG. 7 is a plan view of a counter electrode showing a fourth embodiment, and B and C are plan views of a counter electrode showing a modification of the fourth embodiment;
FIG. 8 is a plan view of a counter electrode according to a fifth embodiment,
FIG. 9A is a sectional view showing a fifth embodiment of the touch sensor of the present invention, FIG. 9B is a transition diagram showing a state of the dielectric constant of the ionizer,
FIG. 10 is a sectional view showing a touch sensor according to a sixth embodiment of the present invention, FIG. 10B is a transition diagram showing the state of the dielectric constant of the ionizer,
[Explanation of symbols]
1,21,31,71,81 Touch sensor
2,22,32,72,82 Frame (fixed part)
3,23,33,43,53,63,73,83 Counter electrode
4,24,34,74,84 Operation surface (insulating sheet)
10 C / V conversion means
11 Clock signal generating means
12 Signal delay means
13 Delay amount detection means
13A AND circuit
13B smoothing means
14 A / D conversion means
15 Control unit
33a, 43a, 53a, 63a slit
33b, 43b, 53b, 63b conductive part
75, 85, 85a-85k Dielectric
C capacitance
d Opposition distance
S Opposing area
ε dielectric constant
H human body (movable electrode)

Claims (8)

A counter electrode provided on the fixed portion side, an insulating operation surface arranged to face the counter electrode, and a capacitance C generated between the movable electrode moving along the operation surface and the counter electrode. And C / V conversion means for detecting as a voltage V according to the magnitude of
A touch sensor, wherein when the movable electrode moves on an operation surface, at least one or more elements of a facing distance, a facing area, or a dielectric constant between the movable electrode and a facing electrode are changed. The touch sensor according to claim 1, wherein one of the counter electrode and the operation surface is a plane, and the other is curved with respect to the plane. 2. The touch sensor according to claim 1, wherein the counter electrode and the operation surface are both formed as flat surfaces, and the counter electrode is provided to be inclined with respect to the operation surface. The touch sensor according to claim 1, wherein the counter electrode is provided in parallel with the operation surface, and a slit having a predetermined width is provided in the counter electrode. The touch according to claim 4, wherein a width dimension of the conductive portion between the adjacent slits formed in the counter electrode is gradually narrowed from one end to the other end. Sensors. The counter electrode is provided in parallel with the operation surface, and has a linear dielectric constant or a dielectric constant depending on the distance from one end to the other end between the operation surface and the counter electrode. The touch sensor according to claim 1, further comprising a dielectric that changes stepwise. Between the operation surface and the counter electrode, dielectrics having a predetermined width dimension and different dielectric constants are juxtaposed, and the dielectrics move from one end to the other end. The touch sensor according to claim 1, wherein the touch sensor is arranged to have a low dielectric constant. The C / V conversion means includes a clock signal generation means for generating a clock signal, and a delay in rising of the clock signal according to a capacitance detected by the counter electrode when the movable electrode moves on the operation surface. Delay means for applying, a smoothing means for generating a signal corresponding to the delay amount given delay with reference to the clock signal which does not pass through the delay means, and an A / D converter for A / D converting the signal corresponding to the change amount The touch sensor according to any one of claims 1 to 7, further comprising: / D conversion means.

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