JP2011033404A - Tactile sensor, touch panel display, and pointing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tactile sensor which senses tangential force a finger receives from a touch plate, and also to provide a touch panel display and a pointing device having the tactile sensor. <P>SOLUTION: The tactile sensor is equipped with: the touch plate 13 the finger 11 touches; an electrode array 14 formed of a plurality of electrodes which is provided on the side of the touch plate 13 opposite the side the finger touches; a capacitance distribution detection means 15 for sensing the spatial distribution of the capacitance between the finger 11 and the electrode array 14; a distribution characteristic quantity extraction means 16 for extracting the characteristic quantity of the spatial distribution of the capacitance on the basis of the sensing result of the capacitance distribution detection means 15; and a tangential force calculation means 17 for calculating the magnitude of the tangential force on the basis of the extraction result of the distribution characteristic quantity extraction means 16 and data 18 which is preset to associate the magnitude of tangential force the finger 11 receives from the touch plate 13 and the characteristic quantity with each other. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a touch sensor used for a touch panel display, a pointing device, and the like, and a touch panel display and a pointing device including the touch sensor.

  An interface device having a touch panel display that performs a GUI (Graphical User Interface) operation by directly touching the touch panel with a finger has been widely used. When an operation is performed by touching the touch panel with a finger, since the finger is flexible, the contact range between the finger and the touch panel becomes an expanded area and cannot be regarded as a point. Therefore, the position of the center of gravity of the contact area between the finger and the touch panel is calculated, and the position is regarded as the contact point between the finger and the touch panel as the fingertip position. A plurality of electrodes are provided along the panel surface on the surface opposite to the surface touched by the finger of the touch panel. Since the finger is a dielectric, when the finger is brought close to the touch panel, the electrode is located between the electrode of the touch panel and the finger. A capacitance is formed. Since this capacitance increases as the electrode is closer to the finger, a change in the capacitance is detected, and the position of the center of gravity of the contact area between the finger and the touch panel is calculated using the detection result.

  The touch panel display is a device that can perform an intuitive operation by matching the fingertip position of the finger touching the touch panel with the cursor position on the display. However, it is difficult to finely adjust the positional relationship between the fingertip position and the cursor position in the vicinity of the target position when the fingertip is moved to the target position with only the position information of the center of gravity of the contact area between the finger and the touch panel. Therefore, there is a possibility that the fingertip position and the cursor position do not coincide with each other and appropriate pointing is not performed.

  From the earnest research conducted by the inventors of the present application, the position of the fingertip position and the cursor position in the vicinity of the target position by using information on the magnitude of the tangential force received by the finger from the touch panel when the finger touches the touch panel. It turns out that the relationship can be fine-tuned. As a means for sensing the magnitude of the tangential force received by the finger from the touch panel, it is conceivable to use a tactile sensor.

  Patent Document 1 discloses a plurality of pressure-sensitive element groups, a first plate-like elastic body provided on the pressure-sensitive element group, and a plurality of columnar bodies provided on the first plate-like elastic body. And a tactile sensor including a second plate-like elastic body provided on the plurality of columnar bodies and a plurality of protrusions provided on the second plate-like elastic body. In the tactile sensor described in Patent Document 1, when an external force is applied to the plurality of protrusions of the second plate-like elastic body, the second plate-like elastic body is elastically deformed and the pressure-sensitive element group is interposed via the columnar body. The first plate elastic body is elastically deformed in some of the pressure sensitive elements, and the first plate elastic body is not elastically deformed or deformed in another pressure sensitive element near the pressure sensitive element. The amount becomes smaller. Therefore, it is supposed that the magnitude of the tangential force can be sensed by detecting the deformation amount.

  However, in the tactile sensor described in Patent Document 1, the second plate-like elastic body provided with a plurality of protrusions to which an external force is applied must be elastically deformed. Therefore, the tactile sensor described in Patent Document 1 has a problem that the magnitude of the tangential force cannot be sensed on a touch panel made of a rigid plate member.

  In addition, the inventors of the present application do not only provide the position information of the center of gravity of the contact area between the finger and the pad but also the pointing device that indicates the position of the cursor displayed on the display by tracing the pad with the finger. It has been found that it is preferable to use information on the magnitude of the tangential force received from the pad. However, since the pad portion traced with the finger of the pointing device is made of a plate member having rigidity, the same problem as described above also occurs in the pointing device.

  The present invention has been made in view of the above problems, and an object thereof is a tactile sensor capable of sensing the magnitude of a tangential force received by a flexible dielectric from a rigid plate-like member, and the tactile sense thereof. To provide a touch panel display and a pointing device provided with a sensor.

In order to achieve the above object, the invention of claim 1 is a tactile sensor, wherein a plate member having rigidity, a plurality of electrodes provided along one side surface of the plate member, and the plate member. When a dielectric material having flexibility is brought into contact with the side surface opposite to the side surface on which the plurality of electrodes are provided, the dielectric material is formed between the dielectric material and the plurality of electrodes via the plate-like member. Capacitance distribution detection means for detecting the distribution state of the electrostatic capacitance, and distribution feature quantity extraction for extracting a predetermined feature quantity of the capacitance distribution state based on a detection result of the capacitance distribution detection means Based on the means, preset data associating the magnitude of the tangential force received by the dielectric from the plate member and the predetermined feature quantity, and the extraction result of the distribution feature quantity extraction means Tangential force calculation means for calculating the magnitude of the tangential force; It is characterized in further comprising a.
According to a second aspect of the present invention, in the tactile sensor according to the first aspect, the predetermined feature amount includes a position of an electrode having a maximum capacitance value among the plurality of electrodes, and the electrostatic capacitance. This is a positional deviation amount from the center of gravity of the spatial distribution of the capacity.
According to a third aspect of the invention, in the tactile sensor of the first or second aspect, the plurality of electrodes are arranged in a two-dimensional matrix.
The invention of claim 4 is a touch panel display comprising a coordinate input surface for receiving input of coordinates by touching a dielectric, and a display screen for displaying an image controlled according to the coordinates input by the coordinate input surface. The tactile sensor according to claim 1, 2 or 3 is provided.
According to a fifth aspect of the present invention, in the pointing device for indicating the position of the pointer displayed on the display means, the touch sensor according to the first, second, or third aspect is provided.

  When a dielectric material having flexibility is brought into contact with a side surface opposite to a side surface on which the plurality of electrodes of the plate-shaped member having rigidity are provided, the plate is changed depending on a contact state between the dielectric material and the plate-shaped member. The distribution state of the capacitance formed between the plurality of electrodes and the dielectric changes via the shaped member. As a result of intensive research, the inventors of the present application have found that there is a correlation between a predetermined feature amount extracted from the distribution state of the capacitance and the magnitude of the tangential force that the dielectric receives from the plate member. I found that there is a relationship.

  In the present invention, a capacitance distribution detecting means detects a distribution state of the capacitance formed between the dielectric and the plurality of electrodes via the plate-like member. Then, the distribution feature amount extraction means extracts a predetermined feature amount of the capacitance distribution state from the detection result. On the basis of the extracted predetermined feature amount and preset data associating the predetermined feature amount with the magnitude of the tangential force received by the dielectric from the plate member, the tangential force calculating means The magnitude of the tangential force is calculated. Therefore, the tangential force that the dielectric receives from the plate member can be sensed.

  As described above, according to the present invention, there is an excellent effect that it is possible to sense the magnitude of a tangential force received by a flexible dielectric from a rigid plate-like member.

The schematic block diagram of a tactile sensor. (A) The schematic diagram which shows the state which pressed the finger | toe 11 straight down with respect to the contact plate 13. FIG. (B) Capacitance distribution diagram in a state where the finger 11 is pressed straight down against the contact plate 13. (A) The schematic diagram which shows the state which moved the finger | toe left with respect to the contact plate. (B) Capacitance distribution diagram in a state where the finger is moved to the left with respect to the contact plate. (A) The schematic diagram which shows the state which moved the finger | toe right with respect to the contact plate. (B) Capacitance distribution diagram with the finger moved to the right with respect to the contact plate. (A) The graph which showed the magnitude | size relationship between the gravity center Xc and the peak Xp in the state which pressed the finger | toe directly on the contact board 13, and the relationship of the electrostatic capacitance distribution shape. (B) The graph which showed the relationship between the magnitude relationship of the gravity center Xc and the peak Xp, and the electrostatic capacitance distribution shape in the state where the finger was moved to the left with respect to the contact plate. (C) The graph which showed the magnitude relationship between the gravity center Xc and the peak Xp, and the relationship with the distribution shape of the capacitance when the finger is moved to the right with respect to the contact plate. The graph which showed the relationship between the deviation | shift amount (| Xp-Xc |) from the symmetry of distribution, and the magnitude | size of a tangential force. Explanatory drawing when calibrating tangential force. The graph which shows the relationship between the distribution feature-value P of an electrostatic capacitance, and the tangential force Ft. The graph which shows the relationship between the distribution feature-value P of an electrostatic capacitance, and the tangential force Ft. The graph which shows the relationship between the distribution feature-value P of an electrostatic capacitance, and the tangential force Ft. (A) The schematic diagram which shows the state which pressed the finger | toe straight down with respect to the contact plate. (B) Capacitance distribution diagram in a state where the finger is pressed straight down against the contact plate. (A) The schematic diagram which shows the state which pressed the finger toward the downward direction further with respect to the contact plate rather than Fig.11 (a). (B) Capacitance distribution diagram in the state of FIG. A graph showing the relationship between the total capacitance and the magnitude of normal force. The graph which showed the relationship between the feature-value of distribution and the magnitude of tangential force / normal force. Explanatory drawing at the time of performing normal force calibration. A graph showing a two-dimensional capacitance distribution. The flowchart which showed an example of the flow of the process performed in a present Example. 1 is a schematic diagram of a mobile device including a pointing device. The schematic block diagram of the tactile sensor mounted in a pointing device. The schematic block diagram of the tactile sensor mounted in a touch panel display. Explanatory drawing when a user calibrates tangential force Ft. Explanatory drawing when a user calibrates normal force Fn.

Hereinafter, an embodiment of the tactile sensor of the present invention will be described.
FIG. 1 is a diagram illustrating the overall configuration of the tactile sensor 10.
The tactile sensor 10 is in contact with a finger 11 and a contact plate 13 (an overlay that is sufficiently harder than a finger, not limited to windshield and glass), and faces the finger 11 (showing a cross section) across the contact plate 13. A plurality of electrode arrays 14 arranged. A capacitor is formed by the electrode array 14 and the dielectric finger 11 with the contact plate 13 interposed therebetween, and a capacitance is formed between the electrode array 14 and the finger 11. In general, the capacitance C when a dielectric having a dielectric constant ε uniformly exists between parallel plate conductors of area S and distance d is C = εS / d. The capacitance formed between the finger 11 varies depending on the distance and area from the finger 11 to each electrode of the electrode array 14 facing the finger 11. That is, the distance between each electrode of the electrode array 14 and the finger 11 decreases, in other words, the distance increases as the finger 11 approaches the contact plate 13. Further, the capacitance increases as the contact area between the finger 11 and the contact plate 13 increases.

  The capacitance distribution state formed between each electrode and the finger 11 is detected by the capacitance distribution detection device 15, and the feature amount of the capacitance spatial distribution is extracted by the distribution feature amount extraction device 16. Then, the tangential force is calculated by the tangential force calculation device 17 from the feature amount of the distribution and the calibration data 18 acquired in advance.

  Next, the distribution of capacitance formed between each electrode and the finger 11 detected by the capacitance distribution detection device 15 will be described. Here, in order to simplify the description, a one-dimensional distribution will be described. FIG. 2A shows a state in which the finger 11 is pressed straight down against the contact plate 13, and the electrostatic capacity distribution formed between each electrode and the finger 11 at that time is shown in FIG. It is shown in the graph of b). Also, Xi in FIG. 2B is the i-th electrode position of the electrode array, and the capacitance between the finger 11 and the electrode detected there is Zi.

  As shown in FIG. 2A, when the finger 11 is pressed straight down against the contact plate 13 and the finger 11 is not displaced in the left-right direction in the figure relative to the contact plate 13, each of the finger 11 and the electrode array 14 Since the distance to the electrode is almost symmetrical in FIG. 2A, the distribution of the capacitance formed between each electrode and the finger 11 detected by the capacitance distribution detecting device 15 is as shown in FIG. As shown in FIG. 2 (b), the shape is nearly symmetrical, and the peak Xp indicating the electrode position where the capacitance value peaks and the centroid Xc indicating the centroid position of the spatial distribution of the capacitance substantially coincide with each other. Yes.

  In a normal capacitive touch panel, the center of gravity of the finger 11 is used to calculate the position of the finger 11 as shown in Equation 1.

  As a method for detecting the capacitance between the finger 11 and the electrode array 14, a relaxation oscillation method, a charge transfer method, a CSA method (CapSense Successive Application), a series capacitance division comparison method, a shunt method, and the like have been proposed. (Reference: transistor technology February 2008 issue pp167-172), these may be used.

  Next, as shown in FIG. 2A, the finger 11 is pressed straight down against the contact plate 13, and the finger 11 is directly moved in the left-right direction in FIG. 2A (the direction along the X axis in FIG. 2B). ) Is considered that the finger 11 is slid.

  In FIG. 3 (a), as shown in FIG. 2 (a), the finger 11 is pressed straight down against the contact plate 13, and the finger 11 is moved to the left in FIG. A state in which a tangential force Ft in the right direction in FIG. 3A is received from the plate 13 is shown.

  In this case, the contact state between the contact plate 13 and the finger 11 is not symmetrical in FIG. Therefore, the distance between the finger 11 and each electrode of the electrode array 14 is also asymmetric in FIG. 3A, and as shown in FIG. 3B, each electrode detected by the capacitance distribution detection device 15 The graph of the electrostatic capacity distribution formed between the finger 11 also has a shape biased to the right side in FIG. In FIG. 3B, the peak Xp indicating the electrode position where the capacitance value reaches its peak is located on the right side in the X-axis direction with respect to the centroid Xc indicating the centroid position of the spatial distribution of the capacitance (Xc <Xp ).

  In FIG. 4 (a), as shown in FIG. 2 (a), the finger 11 is pressed straight down against the contact plate 13, and the finger 11 is moved rightward in FIG. A state in which a tangential force Ft in the left direction in FIG. 4A is received from the plate 13 is shown.

  Also in this case, the contact state between the contact plate 13 and the finger 11 is not symmetrical in FIG. Therefore, the distance between the finger 11 and each electrode of the electrode array 14 is also left-right asymmetric in FIG. 4A, and as shown in FIG. 4B, each electrode and finger detected by the capacitance distribution detection device 15. The graph of the electrostatic capacity distribution formed between the first and second electrodes 11 is also biased to the left in FIG. In FIG. 4B, the peak Xp indicating the electrode position where the capacitance value reaches its peak is located on the left side in the X-axis direction with respect to the center Xc indicating the center of gravity of the spatial distribution of the capacitance (Xc> Xp). ).

  From the above, the relationship between the magnitude relationship between the center of gravity Xc and the peak Xp and the shape of the graph showing the distribution of capacitance formed between each electrode and the finger 11 can be summarized as shown in FIG. a), as shown in FIGS. 5B and 5C. 5A shows a case where the finger 11 is pressed straight down against the contact plate 13 and the finger 11 is not shifted in the horizontal direction with respect to the contact plate 13 (see FIG. 2). FIG. 11 is pressed straight against the contact plate 13 and the finger 11 is slid to the left as it is (see FIG. 3), FIG. 5 (c) presses the finger 11 straight against the contact plate 13 as it is. This is a case where the finger 11 is slid rightward (see FIG. 4).

  Here, when | Xp−Xc | is considered as an example of the amount of deviation from the symmetry of the distribution shape, | Xp−Xc | and the magnitude of the tangential force that the finger 11 receives from the contact plate 13 as shown in FIG. It can be considered that there is some correlation with Ft.

  In advance calibration, the relationship (calibration data 18 shown in FIG. 1) between | Xp−Xc | shown in FIG. 6 and the magnitude Ft of the tangential force received by the finger 11 from the contact plate 13 is acquired and held. If this is done, the magnitude Ft of the tangential force that the finger 11 receives from the contact plate 13 is determined from the distribution of the capacitance formed between each electrode and the finger 11 detected by the capacitance distribution detector 15. Obtainable.

<Tangential force calibration>
As shown in FIG. 7, the force sensor 50 is attached to the side end of the mobile device 60 on which the tactile sensor 10 is mounted, and the mobile device 60 is slowly pressed against the wall 70 with the finger 11. At this time, if the roller 61 is attached to the mobile device 60 so that the friction received by the mobile device 60 from the floor 80 is sufficiently small, the output Ft ′ of the force sensor 50 and the tangential force Ft received by the finger 11 become equal. As a result, if the capacitance distribution feature amount is P, one curve of the known tangential force Ft and the capacitance distribution feature amount P at that time is obtained. The capacitance distribution feature amount P is, for example, the deviation amount | Xp−Xc | from the symmetry of the distribution shape described above.

  Here, if the finger to be used is limited to the index finger, the characteristic of the fingertip varies depending on the person. For this reason, it is assumed that the above-described measurement is performed on a plurality of persons and, for example, the curve patterns are classified as shown in FIG.

  The above data is created in advance. In calibration when the user starts use, a set of (P, Ft) is measured by a method described later, and the curve is estimated. If (P, Ft) is the coordinate position at which the circle in FIG. 9 is located, the characteristic of this user's finger is the curve I, so that the tangential force Ft can be obtained from the distribution feature amount P of any capacitance. Is obtained.

  For example, if (P, Ft) is the coordinate position where the circle in FIG. 10 is located, a curve obtained by interpolation between curve I and curve II (a curve indicated by a dotted line in the figure) may be used. it can.

Next, the magnitude Fn of the normal force that the finger 11 receives in the normal direction from the contact plate 13 will be considered.
When the finger 11 is pressed straight against the contact plate 13 as shown in FIG. 11 (a), and the finger 11 is pressed downward against the contact plate 13 as shown in FIG. Since the contact area between the contact plate 13 and the contact plate 13 becomes large, each electrostatic capacity Zi detected (sensed) by the electrostatic capacity distribution detecting device 15 is generally shown in FIG. larger than b).

From this, the total capacitance Z ₀ formed between each electrode and the finger 11 that can be calculated using Equation 2, and the normal force that the finger 11 receives from the contact plate 13 in the normal direction. It is considered that there is some relationship between Fn and Fn as shown in FIG.

  Therefore, in the prior calibration, the total capacitance Z0 formed between each electrode and the finger 11 and the magnitude Fn of the normal force that the finger 11 receives from the contact plate 13 in the normal direction. If the relationship is acquired and held, the normal force magnitude Fn can be obtained from the capacitance distribution formed between each electrode and the finger 11 detected by the capacitance distribution detector 15. it can.

Furthermore, taking into consideration that there is some relationship between the total capacitance Z ₀ formed between the electrodes and the finger 11 and | Xp−Xc |, as shown in FIG. The magnitude of the tangential force Ft and the magnitude of the normal force Fn can be obtained from the feature quantity of a simple distribution shape.

<Normal force calibration>
As shown in FIG. 15, the force sensor 50 is disposed between the back surface of the mobile device 60 on which the tactile sensor 10 is mounted and the floor 80, and the finger 11 performs an operation of slowly pressing the mobile device 60 against the floor 80. Due to the action and reaction of the force, the output Fn ′ of the force sensor 50 and the normal force Fn received by the finger 11 become equal. As a result, if the capacitance distribution feature amount is P, one curve of the known normal force Fn and the capacitance distribution feature amount P at that time is obtained. The capacitance distribution feature amount P is, for example, the above-described total capacitance Z _{0 of the} capacitance.

  Up to this point, the distribution of capacitance formed between the electrodes and the finger 11 has been described with reference to a one-dimensional example. However, as illustrated in FIG. It may be a distribution of capacitance formed between the electrodes and the finger 11. In this case, if the following Equation 3 is used instead of | Xp−Xc |, the same argument as before will be established.

FIG. 17 is a flowchart showing an example of the flow of processing performed in the present embodiment.
The calibration data created in advance is read and stored on the memory (S1). Next, the distribution state of the capacitance formed between the finger 11 and each electrode detected from each electrode array 14 is detected by the capacitance distribution detection device 15 (S2). The feature amount of the capacitance distribution state detected by the capacitance distribution detection device 15 is calculated (S3), and the tangent that the finger 11 receives from the contact plate 13 from the calculated feature amount and the calibration data. A tangential force magnitude Ft, which is a directional force, and a normal force magnitude Fn, which is a normal direction force received by the finger 11 from the contact plate 13, are calculated by the tangential force calculation device 17 or the like (S4).

  Next, a case where the tactile sensor of the present invention is mounted on the pointing device 20 used in mobile devices such as the PDA 100, the mobile personal computer 101, and the mobile phone 102 as shown in FIG. 18 will be described.

  In the tactile sensor having the same configuration as that shown in FIG. 1, the capacitance distribution detection device, the distribution feature amount extraction device, the tangential force calculation device, the storage device in which calibration data is stored, and the like shown in FIG. In the sensor signal processing unit 22, the processing of the flowchart shown in FIG. 17 is performed. The contact plate 23 of the pointing device 20 is sized so that only the fingertip can be placed thereon, and the electrodes provided on the contact plate 23 are in a two-dimensional matrix (electrode matrix 24). A pointing device 20 having a tactile sensor composed of such modules is mounted on a mobile device and used for moving the cursor on the screen. The cursor position is obtained by integrating (adding) a tangential force Ft, which is a tangential force received by the finger 21 from the contact plate 23 generated when the fingertip is shifted from the center position of the contact plate 23.

  As a pointing device in PDA (Personal Digital (Data) Assistants), mobile personal computers, mobile phones and other mobile devices, the fingertip position is sensed in a certain area corresponding to the screen, such as a touchpad (name varies depending on the manufacturer). However, since the mouse cursor is moved on the screen, it is necessary to increase the size of the pad to some extent, which is not suitable for miniaturization.

  In small devices, it is common to use a pointing stick (name varies depending on the manufacturer) as a pointing device, but the pointing stick senses a tangential force using a pressure sensor with a mechanism that deforms and moves, and moves the cursor. It is not necessary to slide your finger or move it much like a touchpad, and it can be made compact. However, since the pointing stick has a movable part, there are problems such as deterioration, calibration, and dirt.

  On the other hand, the pointing device 20 equipped with the tactile sensor of the present invention has a simple configuration having no movable parts such as a contact plate 23 and an electrode matrix 24 which is an electrode group, and thus can be miniaturized like a pointing stick. And the effect that thickness reduction, high durability, and cleanliness like a touchpad are realizable is acquired.

  Next, a case where the touch sensor of the present invention is mounted on a touch panel display used in a mobile device such as a PDA, a mobile personal computer, or a mobile phone will be described.

  As shown in FIG. 20, the touch panel display 30 includes display modules such as a display panel 35 and a display control unit 37, a transparent cover glass 33 is used as a contact plate, and ITO (Indium Tin Oxide) is provided as an electrode provided on the cover glass 33. A transparent electrode 34 such as an electrode is used.

  The sensor signal processing unit 36 including a capacitance distribution detection device, a distribution feature amount extraction device, a tangential force calculation device, and a storage device in which calibration data is stored performs the processing of the flowchart shown in FIG. The equivalent fingertip position is obtained from the gravity center position Xc of the capacitance distribution, and includes force information (a tangential force Ft which is a tangential force received by the finger 31 from the cover glass 33 and a normal direction received by the finger 31 from the cover glass 33. The normal force Fn), which is a force, is calculated from the characteristic amount (deviation amount and sum) of the capacitance distribution as described above.

  Further, for example, a large cursor movement may be performed at the center of gravity position Xc as usual, and a small fine adjustment near the target position may be performed by adding a tangential force Ft.

  The touch panel display is a device that sells intuitive operations because the touched fingertip position matches the cursor position on the display screen, but the position information alone is not enough to move the fingertip to the target position / trajectory. There is a problem that it is difficult to finely adjust the fingertip position and the cursor position.

  In the touch panel display 30 provided with the tactile sensor of the present invention, it is possible to add a function equivalent to the transparent pointing device to the entire screen area to be touched.

It is assumed that the cursor moves slowly with respect to a small tangential force Ft, and that the cursor moves greatly with a large tangential force Ft.
In a two-dimensional example, Equation 4 is obtained.

The cursor position at time t is integrated as shown in Equation 5.

Furthermore, when it discretizes, it becomes like Formula 6.

  The constant α can be made variable according to the user's preference.

  By performing the operation as described above, the user can accurately stop the target position by adjusting (gradually decreasing) the tangential force Ft as the cursor approaches the desired target position. it can.

  As a result, a large cursor movement is performed at the center of gravity position as before, and a small fine adjustment near the target position is moved by the tangential force Ft, thereby realizing a finer operation.

Here, an example of a simple calibration method performed when the user uses the mobile device 90 provided with the touch sensor 10 of the present invention and provided with a pointing device or a touch panel display will be described.
First, when the user calibrates the tangential force Ft, as shown in FIG. 21, the mobile device 90 equipped with the tactile sensor 10 is pressed against the wall 70 and supported by the finger 11 so as not to fall. For example, if a roller 91 is installed on the back surface of the mobile device 90, the tangential force Ft is a weight Mg (mass M, gravitational acceleration) of the entire mobile device. g). As a result, one set (P, Ft) of the capacitance distribution feature amount P and the known Mg (= Ft ′ = Ft) is obtained. Subsequent processing is the same as the above-described “<tangential force calibration>”.

  Next, when the user calibrates the normal force Fn, in other words, as shown in FIG. 22, the surface of the mobile device 90 that contacts the 11 of the tactile sensor 10 faces the floor 80. For example, the mobile device 90 is placed on the belly of the finger 11 so as to face downward in the direction of gravity. Since the weight Mg of the mobile device 90 becomes the normal force Fn as it is due to the action and reaction of the force, a set (P, Fn) of the capacitance distribution feature amount P and the known Mg (= Fn ′ = Fn) One will be obtained. Subsequent processing is the same as the above-described “<normal force calibration>”.

As described above, according to the present embodiment, in the tactile sensor 10, the contact plate 13 that is a rigid plate-like member, and the electrode array 14 that is a plurality of electrodes provided along one side surface of the contact plate 13, When the finger 11, which is a flexible dielectric, is brought into contact with the side surface opposite to the side surface on which the electrode array 14 of the contact plate 13 is provided, the finger 11 and the plurality of electrodes are connected via the contact plate 13. An electrostatic capacity distribution detecting device 15 which is an electrostatic capacity distribution detecting means for detecting an electrostatic capacity distribution state formed therebetween, and the electrostatic capacity distribution based on the detection result of the electrostatic capacity distribution detecting device 15; A distribution feature quantity extraction device 16 that is a distribution feature quantity extraction means for extracting a predetermined feature quantity of a state, an extraction result of the distribution feature quantity extraction device 16, and a magnitude of a tangential force that the finger 11 receives from the contact plate 13. And the feature amount Provided with calibration data 18 is because the data set, the tangential force calculating unit 17 is a tangential force calculating means for calculating the magnitude of the tangential force on the basis of, a. Thereby, the electrostatic capacitance distribution detection device 15 detects the distribution state of the electrostatic capacitance formed between the finger 11 and the plurality of electrodes via the contact plate 13. Then, the distribution feature quantity extraction device 16 extracts a predetermined feature quantity of the capacitance distribution state from the detection result. Based on the extracted predetermined feature amount and the calibration data 18, the tangential force calculation device 17 calculates the magnitude of the force in the tangential direction. Therefore, the tangential force received by the finger 11 from the contact plate 13 by the tactile sensor 10 can be sensed.
Further, according to the present embodiment, as the predetermined feature amount, the position of the electrode having the largest capacitance value among the plurality of electrodes and the barycentric position of the spatial distribution of the capacitance The amount of misregistration may be used.
Further, according to the present embodiment, the magnitude of the tangential force that the finger 11 receives from the contact plate 13 can be sensed even when the electrode array 14 is arranged in a two-dimensional matrix.
In addition, according to the present embodiment, by using the tactile sensor of the present invention for the touch panel display, as described above, the large cursor movement is performed at the center of gravity as before, and the small fine adjustment near the target position is performed by the tangential force Ft. By moving, it becomes possible to realize more detailed operations.
In addition, according to the present embodiment, by using the tactile sensor of the present invention for the pointing device, since it is a simple structure without a movable part such as a contact plate and an electrode group, it can be miniaturized like a pointing stick, Moreover, it can be made thin, high durability, and cleanliness like a touch pad.

  In this embodiment, the case where the finger 11 is brought into contact with the contact plate 13 of the tactile sensor 10 has been described. However, a dielectric material having a flexibility that can be deformed when brought into contact with the contact plate 13 (having a large dielectric constant). If it is preferable, it is not limited to the finger 11 to be brought into contact with the contact plate 13, and various effects similar to those described above can be obtained.

DESCRIPTION OF SYMBOLS 10 Tactile sensor 11 Finger 13 Contact board 14 Electrode array 15 Capacitance distribution detection device 16 Distribution feature quantity extraction device 17 Tangential force calculation device 18 Calibration data 20 Pointing device 21 Finger 22 Sensor signal processing unit 23 Contact plate 24 Electrode matrix 30 Touch panel display 31 Finger 33 Cover glass 34 Transparent electrode 35 Display panel 36 Sensor signal processing unit 37 Display control unit 50 Force sensor 60 Mobile device 61 Roller 70 Wall 80 Floor 90 Mobile device 91 Roller 101 Mobile PC 102 Mobile phone

JP 2006-250705 A

Claims (5)

A plate-like member having rigidity;
A plurality of electrodes provided along one side surface of the plate-like member;
When a flexible dielectric is brought into contact with the side surface opposite to the side surface on which the plurality of electrodes of the plate member are provided, the dielectric and the plurality of electrodes are interposed via the plate member. A capacitance distribution detecting means for detecting a distribution state of the capacitance formed therebetween;
A distribution feature amount extraction unit that extracts a predetermined feature amount of the capacitance distribution state based on a detection result of the capacitance distribution detection unit;
Based on preset data that associates the magnitude of the tangential force that the dielectric receives from the plate-like member with the predetermined feature amount, and the extraction result of the distribution feature amount extraction means, the tangential direction force Tangential force calculation means for calculating the magnitude of the force;
A tactile sensor comprising: The tactile sensor according to claim 1.
The predetermined feature amount is a positional deviation amount between the position of the electrode having the largest capacitance value among the plurality of electrodes and the centroid position of the spatial distribution of the capacitance. A tactile sensor. The tactile sensor according to claim 1 or 2,
A tactile sensor, wherein the plurality of electrodes are arranged in a two-dimensional matrix. A coordinate input surface that accepts input of coordinates by touching a dielectric,
In a touch panel display including a display screen that displays an image controlled according to coordinates input by the coordinate input surface.
A touch panel display comprising the tactile sensor according to claim 1, 2 or 3. In a pointing device that indicates the position of the pointer displayed on the display means,
A pointing device comprising the tactile sensor according to claim 1, 2 or 3.

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