JP5549068B2 - Input device - Google Patents

Description

The present invention relates to an input device such as a touch switch that employs a capacitive coupling method as an input method.

Conventionally, touch switches and touch panels have been known as input devices using capacitive coupling.
The capacitively coupled touch switch includes a panel switch and a control board. The panel switch is composed of an electrode sheet obtained by printing a silver paste or the like as a switch electrode on a PET film and attached to an insulating base material such as acrylic or glass with an adhesive (double-sided tape or the like).
When a finger or a conductive member approaches the switch electrode, a parallel plate capacitor in which an insulating substrate is sandwiched between the electrode and the finger is formed, and capacitance is generated. This change in capacitance is converted to voltage by a C / V conversion circuit (circuit that converts capacitance to voltage), and is converted to digital data by an A / D converter (analog / digital converter). The on / off state of the switch is determined (see Japanese Patent Laid-Open No. 2005-18669 (Patent Document 1)).

  The capacitively coupled touch switch is a digital input device that defines an electrode as a switch, detects that a finger has approached the electrode, and detects on / off. On the other hand, the touch panel is an analog input device that detects a position where a conductor such as a finger approaches, and detects a numerical value.

In the capacitive coupling type input device, for example, there is a method of mixing the required number of touch switches and the required number of touch panels in the input device in order to mix the digital input unit and the analog input unit. However, in this method, the specific area is either a digital input section or an analog input section, and both cannot be mixed in the same area. In addition, there is a limitation that the switch configuration cannot be changed without changing the electrode configuration.
Moreover, in the method using a touch switch and a touch panel, it is necessary to combine two types of input devices with different methods, and there is a tendency that the types and the number of components increase.

JP 2005-18669 A

The present invention has been made in consideration of such points, and in an input device using capacitive coupling, a digital input unit and an analog input unit or a plurality of analog input units having different meanings are mixed in the same region. It is an object of the present invention to provide an input device that enables various inputs with a small number of components and gives a new feeling to the user by switching them automatically.

The present invention provides a plurality of switch electrodes formed on the back surface of an insulating substrate so as not to be in electrical contact with each other, and a capacitance generated by the proximity and contact of a conductor such as a finger to the surface of the insulating substrate. And detecting the proximity and contact of a conductor such as a finger to the surface of the insulating base based on the detected amount of change in capacitance, and Among the switch electrodes, at least a plurality of switch electrodes adjacent to each other are regarded as a one-dimensional numerical input unit, and an analog input unit that outputs a position where a conductor such as the finger is in proximity is provided. At least a plurality of analog input units that share the switch electrode, and a digital input unit that outputs an on / off state of the plurality of switch electrodes, in the case of a plurality, at least the analog input unit and the digital input unit The digital input but set so as not to overlap with each other, in two adjacent levels of the far proximity and near proximity, and different said analog input unit
The position output based on the setting of the part or the output of the on / off state is performed, and when the conductor such as the finger maintains the far proximity level for a predetermined time, the output based on the setting of the far proximity level is performed. In at least a plurality of analog input units sharing the same switch electrode, when a conductor such as the finger first comes close to and contacts the shared switch electrode, the conductor such as the finger The present invention proposes an input device including switch recognition means for outputting a position after moving to a switch electrode not shared by a plurality of analog input units.

In the input device according to the present invention, for example, a state where the finger is brought close to the input panel to some extent (far-close state), a state where the finger is further brought closer to the input panel, preferably a state where the finger is in contact with the insulating substrate ( In a close proximity state, different inputs can be made, so a specific area has a different meaning from an analog input unit in a close proximity state, a digital input unit in a close proximity state, or a far proximity state in a close proximity state. Users can switch automatically without switching the input function by means such as an analog input unit that has more input units and various operations with fewer components and procedures. It is possible to give a new feeling to the user.
Since multiple input units can be mixed in the same area, when the size of the input panel is limited, the size of each input unit is made relatively large so that the user can operate it easily. can do.

Further, the switch configuration can be changed by changing the digital input unit or the analog input unit without changing the electrode configuration or during operation. For example, for the digital input unit, the number of digital input units can be changed by changing the setting of the digital input unit along the longitudinal direction, that is, the virtual switch division, in the band-shaped switch electrode. Regarding the analog input unit, in some cases, the entire longitudinal direction of the strip-shaped switch electrode is used as one analog input unit, and in other cases, the strip-shaped switch electrode is virtually divided in the longitudinal direction into two analog input units. be able to.
In this case, by making the input panel transparent and installing a display device such as a liquid crystal underneath, the switch configuration can be switched and at the same time the changed switch configuration can be illustrated and the finger is not in the vicinity If the display is automatically changed to a content suitable for each state in the close proximity state and the close proximity state, more useful feedback can be given to the user.

Hereinafter, preferred embodiments of an input device according to the present invention will be described in detail with reference to the accompanying drawings.
<First Embodiment>
FIG. 1 is a configuration diagram illustrating an example of an input device according to the first embodiment. The switch electrode 1 is a uniform resistor in which a silver paste or the like is printed on a substantially rectangular area on the PET film. The switch electrode 1 needs to have a strip shape. Here, the shape is substantially rectangular, but other shapes such as an ellipse or a curve may be used as long as they do not branch or have a large change in width. The proximity position of the finger is calculated on a one-dimensional coordinate axis along the longitudinal direction of the band-shaped switch electrode. If the shape is rectangular or elliptical, the long axis is calculated. To do.
The switch electrode 1 is fixed to an insulating base material (not shown) such as acrylic or glass to form an input panel. A state where a conductor such as a finger is brought close to the input panel to some extent is a far-close state, and a state where the conductor such as a finger is further brought closer to the input panel and is preferably in contact with the insulating base material.

Lead wires are connected to both ends of the substantially rectangular long axis of the switch electrode 1, and either one of them can be connected to the capacitance / electric resistance detection means 3 by the switch 2. The capacitance / electric resistance detection means 3 is an oscillation circuit (not shown) formed by a resistor and a capacitor, for example, and the switch electrode 1 is a part of the circuit. For this reason, the capacitance increases due to the proximity of a conductor such as a finger, and the oscillation frequency changes. Usually, the change in capacitance due to the proximity of a finger is about 0.1 pF. The capacitance / electric resistance detection means 3 outputs a pulse train that oscillates at an oscillation frequency determined by the additional capacitance and electric resistance determined by the relationship between the resistor and the capacitor, and the switch electrode 1 and the finger. For this reason, the electrical resistance value of the switch electrode 1 should not be significantly different from the electrical resistance value of the resistor used in the oscillation circuit. As the capacitance / electrical resistance detection means 3, it is possible to use a device such as 555 which is very common as a timer IC and is often used in an oscillation circuit. The oscillation frequency is preferably about 100 kHz so that the period can be measured by a general microprocessor and the change in capacitance / electric resistance can be detected.

  The switch recognition unit 4 measures the period of the pulse train output by the capacitance / electric resistance detection unit 3. The switch recognizing means 4 determines the proximity level of a conductor such as a finger, that is, whether the conductor such as a finger is not in the vicinity, is in a close proximity state, or is in a close proximity state. The calculation is performed on the long axis of the electrode 1 and the switch information is output to a device (not shown) that uses the switch information. The switch recognition unit 4 can be realized by a microprocessor or the like that packages peripheral functions such as a timer and a memory and can incorporate software. In order to measure the period of the pulse train, for example, an input capture function of a microprocessor can be used.

Next, a method in which the switch recognition unit 4 calculates the finger proximity level and the position of the switch electrode 1 on the long axis will be described.
In general, the oscillation frequency of an oscillation circuit formed by a resistor and a capacitor is proportional to 1 / (RC) ^1/2 expressed using the electric resistance value R of the resistor and the capacitance C of the capacitor. The oscillation frequency determined by the capacitance / electric resistance detection means 3 and the switch electrode 1 changes as follows according to the proximity of the finger. When the finger is close to the switch electrode 1, a parallel plate capacitor in which an insulating base material is sandwiched between the finger and the switch electrode 1 is formed. The capacitance of this capacitor increases as the finger approaches the switch electrode 1. For this reason, the oscillation frequency decreases as the finger approaches the switch electrode 1, and the period increases. Further, when the proximity position of the finger to the switch electrode 1 is moved along the major axis direction of the substantially rectangular switch electrode 1, the distance from the finger to both ends of the major axis of the switch electrode 1 changes, and accordingly. The electrical resistance changes. Depending on the position of the finger in the switch electrode 1, the greater the electrical resistance, the lower the oscillation frequency and the longer the period.

Now, assuming that the major axis direction of the substantially rectangular switch electrode 1 is right and left, the finger is close when the left end of the switch electrode 1 is connected to the capacitance / electric resistance detection means 3 by the switch 2. _Let ΔT _{L be} the amount of change in the oscillation period from the absence, and ΔT _R be the amount of change in the oscillation cycle when the right end is connected. If the left end of the long axis of the switch electrode 1 is 0 and the right end is 1, the proximity position of the finger to the switch electrode 1 can be calculated by ΔT _R / (ΔT _R + ΔT _L ).

The proximity level of the finger is determined by the magnitude of (ΔT _R + ΔT _L ). Here, the proximity level is divided into two states, a far-close state and a close-close state. Two thresholds are provided, and threshold 1 <threshold 2 is set. When the magnitude of (ΔT _R + ΔT _L ) is larger than the threshold value 1 and smaller than the threshold value 2, it is determined that the distance is close and when it is larger than the threshold value 2, it is determined that the distance is close. Since the relationship between the proximity state of the finger and the threshold value depends on the shape, size, electrical resistance value, circuit constant, and the like of the electrode switch, it is determined by measuring with an actual configuration. It is possible to increase the proximity level by fixing or specifying the user or limiting the state of the finger to be used.

  The amount of change in the oscillation period varies depending on the size of the finger. For the same threshold, a large finger is determined to be in a close proximity state farther from the electrode switch, while a small finger is not determined to be in a close proximity state unless it is closer to the electrode switch. Further, when the finger approaches the electrode switch, it is determined that the large finger has changed from the close proximity state to the close proximity state at a greater distance than the small finger. When determining the two thresholds, data is collected with fingers of various sizes or finger-substituting conductive members, and the threshold 1 is the distance that a small finger is considered to be close to, so that a small finger can be placed in a close proximity state. It is desirable to set a numerical value close to the upper limit of the data when the finger having a small threshold contacts the insulating base material so as not to erroneously shift from the close proximity state to the close proximity state.

  Next, a method in which the switch recognition unit 4 determines what operation has been performed using the proximity state of the finger and the position on the long axis of the switch electrode 1 will be described. At the time of design, a switch in the direction along the long axis of the switch electrode 1 in the near-close state and the close-close state is defined in advance and stored in the switch recognition unit 4. However, a plurality of switch definitions may be prepared and switched during operation. The definition of the switch is as follows (see FIG. 2).

  In the far and close state, one or more analog inputs 5 and 6 can be defined. Here, the analog input units 5 and 6 input a numerical value corresponding to a one-dimensional position in the direction along the long axis in a rectangular region obtained by dividing the substantially rectangular switch electrode 1 along the long axis. Is. One or a plurality of analog input portions 5 and 6 that do not overlap each other can be defined in an arbitrary region between both ends of the long axis of the switch electrode 1. However, even if the finger is in the close proximity state, the user may intend to bring the finger closer to the switch electrode 1 to make the close proximity state. Accordingly, the switch recognizing means 4 starts analog input if the distant proximity state is still maintained after several hundreds of milliseconds have elapsed since the finger has become the close proximity state. After the analog input is started, the analog input is terminated when the finger leaves the far proximity state or the finger shifts to the near proximity state.

In addition, since the switch electrode 1 is not a complete one-dimensional structure but has a band shape and a width, the calculated position includes an error. For this reason, when defining the plurality of analog input portions 5 and 6, it is necessary to provide a buffer zone that does not belong to at least any analog input portion between them. In particular, in the state of close proximity, since the finger is in the air, it is preferable to increase the width of the buffer zone. Furthermore, when the finger is in the air, the distance of the finger with respect to the switch electrode 1 tends not to be constant in time. This causes jitter at the calculated position. It is preferable that the switch recognition unit 4 or the apparatus using the switch information removes jitter by adding a temporal moving average process to the calculated position. Further, in consideration of errors and jitter caused by the structure of the switch electrode 1, it is better not to increase the resolution of the analog input units 5 and 6 too much.

On the other hand, in the close proximity state, one or more analog input units 9 and one or more digital input units 7 and 8 can be defined. Here, the digital input units 7 and 8 are the on state of the input unit when a finger is in a close proximity state in a rectangular region obtained by dividing the substantially rectangular switch electrode 1 along the long axis. An off state is input when the state is approached after exiting the close proximity state. When providing a plurality of input parts, as in the far-and-close state, it is necessary to provide a buffer zone between them.
Here, the digital input section is not defined in the close proximity state, but if it is an analog input, the user can recognize the analog input by performing an operation of moving the finger in the close proximity state. This is because the user has determined that the feeling of use is unnatural because the user has to place the finger in a close proximity state and keep it away. However, if the operation procedure is devised or sufficient feedback is provided to the user by another means, it is possible to define the digital input unit in a far-close state.

<Second Embodiment>
FIG. 3 is a configuration diagram illustrating an example of an input device according to the second embodiment. The difference from the first embodiment is that the plurality of switch electrodes 10 to 13 are arranged in a row so as not to be electrically connected to each other, and the oscillation period does not change greatly depending on the proximity position of the finger to each inside. As described above, the electrical resistance value is smaller than the electrical resistance value of the resistor forming the oscillation circuit of the electrostatic capacitance detecting means 15, and each switch 14 is connected to a single lead wire. That is, the connection of the plurality of switch electrodes 10 to 13 to the capacitance detecting means 15 is switched. The capacitance detection means 15 is the same in configuration as the capacitance / electric resistance detection means 3 in the first embodiment. In this embodiment, the capacitance detection means 15 is a finger to a plurality of switch electrodes 10 to 13. This is for detecting the amount of change in capacitance due to the proximity of.

The proximity level of the finger is the amount of change ΔT _{10 to} ΔT in the oscillation period from the state where the finger is not in proximity when each of the plurality of switch electrodes 10 to 13 is connected to the capacitance detection means 15 by the switch 14. Judgment is made according to the size of ₁₃ . Here, as in the first embodiment, the proximity level is divided into two states, a far-close state and a near-close state. Two thresholds are provided, and threshold 1 <threshold 2 is set. When the magnitudes of ΔT _{10 to} ΔT ₁₃ are larger than the threshold 1 and smaller than the threshold 2, the corresponding switch electrodes 10 to 13 are determined to be in the close proximity state, and when larger than the threshold 2, the near proximity state is determined. The relationship between the proximity state of the finger and the threshold value depends on the shape, size, electrical resistance value, circuit constants, and the like of the plurality of electrode switches 10 to 13, and therefore, it is necessary to determine by measuring with an actual configuration. This is the same as in the first embodiment.

  Next, a method in which the switch recognition unit 16 determines what operation has been performed using the proximity state of the finger will be described. At the time of designing, the switches of the plurality of switch electrodes 10 to 13 in the near-close state and the close-close state are defined in advance and stored in the switch recognition unit 16. The definition of the switch is as follows (see FIG. 4).

  One or more analog inputs 17 can be defined in the far / close state. Here, the analog input unit 17 is for inputting a numerical value corresponding to a one-dimensional position in a direction along a line in which the plurality of switch electrodes 10 to 13 are arranged. However, the resolution is equal to the number of the plurality of switch electrodes 10 to 13 or when it is determined that the adjacent switch electrodes are in a close proximity state at the same time, the finger is located between the switch electrodes, At most, the number of electrodes 10 to 13 is at most doubled.

On the other hand, in the close proximity state, one or more analog input units 18 and one or more digital input units 19 and 20 can be defined. Here, the digital input units 19 and 20 indicate that the switch electrode is turned on when the finger is in the close proximity state for each of the plurality of switch electrodes 10 to 13 after the switch electrode is in the close proximity state. When the state is exited, the off state is input.
Further, in the present embodiment, by arranging the plurality of switch electrodes 10 to 13 in a two-dimensional manner, different analog input portions can be realized while sharing some of the switch electrodes.

Hereinafter, the present invention will be described with reference to examples and comparative 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
This example corresponds to the first embodiment. The apparatus shown in FIG. 1 is configured, and switch information is output from the switch recognition unit 4 by serial communication and is taken into a personal computer. As shown in FIG. 5, in the switch definition, the entire surface of the switch electrode 1 is used as the analog input unit 21 in the close-and-close state, and the switch electrode 1 is divided into three regions in the close-and-close state, and each of them is the digital input unit 22. To 24. The width of the buffer zone between the three digital input units 22 to 24 was 10% of the length of the long axis of the switch electrode 1.

Create test software on a personal computer, display an image corresponding to the switch electrode 1 on the screen of the personal computer, and change and use the displayed image based on the switch information output from the switch recognition means 4 Feedback was provided.
The display was created by classifying into three types: a state in which nothing was detected, a far-near state, and a near-near state. In a state in which nothing is detected, three rectangles indicating the digital input units 22 to 24 defined in the close proximity state are displayed. This is because, in the present embodiment, since there is one analog input section defined in the far and close state, it is considered preferable to display a digital input section that is considered to be better registered in advance. In the close proximity state, a slider that moves to the left and right according to the position of the finger is displayed. In the close proximity state, three rectangles corresponding to the digital input units 22 to 24 and the finger in the close proximity state at that time The digital input part in is now highlighted.

In this example, display was performed on a personal computer for testing, but in an actual product, the switch electrode 1 was formed of a transparent conductor such as ITO (indium tin oxide) or zinc oxide, and a liquid crystal display device or the like behind the switch electrode 1 By providing a similar display, direct feedback can be provided by the user.

(Comparative Example 1)
As a comparative example, a capacitive coupling type input device having one analog input unit 25 and three digital input units 26 to 28 as shown in FIG. 6 was configured. However, the area and the outer shape occupied by one analog input unit 25 and the three digital input units 26 to 28 are the same as the area and outer shape of the switch electrode 1 of the first embodiment.

  In any of the configurations shown in Example 1 and Comparative Example 1, one type of analog input and three types of digital input could be performed. However, in Comparative Example 1, the area of each input unit was small and it was difficult to input, whereas in Example 1, analog input and digital input were performed in the close proximity state and the close proximity state. Since switching is performed, the area of each input unit is relatively large, and it is not difficult to input. Therefore, since the input device according to the present invention can mix a plurality of input units in the same region, particularly when the size of the input panel is limited, the size of each input unit is relatively set. It was confirmed that it can be enlarged and can be easily operated by the user.

(Example 2)
This example corresponds to the second embodiment. An apparatus as shown in FIG. 3 is configured (however, the number of switch electrodes 29 to 33 is five), and switch information is output from the switch recognition means 16 by serial communication and is taken into a personal computer. As shown in FIG. 7, the switch definition includes the switch electrodes 29 to 31 as the analog input unit 34, the switch electrodes 29, 32, and 33 as the analog input unit 35 in the close proximity state, and the switch electrodes 29 to 31 in the close proximity state. 33 is five digital input sections 36-40.

Test software is created on the personal computer, images corresponding to the switch electrodes 29 to 33 are displayed on the personal computer screen, and the displayed image is changed based on the switch information output from the switch recognition means 16. Feedback to the user.
The display was created by classifying into three types: a state in which nothing was detected, a far-near state, and a near-near state. In a state where nothing is detected, five rectangles indicating the digital input units 36 to 40 defined in the close proximity state are displayed. This is because in the present embodiment, there are two analog input sections defined in the state of close proximity, but since it is not difficult to understand because they are orthogonal to each other, it is considered better to register the position in advance. This is because it is preferable to display the digital input unit. Also, a slider that moves to the left or right or up and down corresponding to the position of the finger is displayed in the far and close state. At this time, when the finger first approaches the switch electrode 29, it is unclear which one of the analog input units 34 and 35 is pointed to. Therefore, when the finger approaches the switch electrode 30 thereafter, the analog input unit 34. Is recognized as pointing to the analog input unit 35 when close to the switch electrode 32, and the display change is started from that point. Further, in the close proximity state, five rectangles corresponding to the digital input portions 36 to 40 and the digital input portion in which the finger is in the close proximity state are highlighted.

In this example, display was performed on a personal computer for testing, but in an actual product, the switch electrode 1 was formed of a transparent conductor such as ITO (indium tin oxide) or zinc oxide, and a liquid crystal display device or the like behind the switch electrode 1 By providing a similar display, direct feedback can be provided by the user.

(Comparative Example 2)
As a comparative example, a capacitively coupled input device having one analog input unit 41 and two digital input units 42 and 43 as shown in FIG. However, the area and the outer shape occupied by one analog input unit 41 and the two digital input units 42 and 43 are the same as the area and outer shape of the switch electrodes 29 to 33 of the second embodiment.

  In the configuration shown in Example 2, two types of analog inputs and five types of digital inputs could be performed. On the other hand, in the configuration shown in Comparative Example 2, only one type of analog input and two types of digital input can be performed. However, the resolution of the two types of analog input units of the second embodiment is inferior to the resolution of one type of analog input unit of the second comparative example. For this reason, it is preferable to employ the configuration shown in the second embodiment for an application where the resolution may be low at least for the analog input. From the above results, it was confirmed that the input device according to the present invention can have a plurality of input units coexisting in the same region, and thus can realize a larger number of input units with fewer components.

The block diagram which shows an example of the input device which becomes 1st Embodiment The figure which shows the example of a switch definition of the input device which becomes 1st Embodiment The block diagram which shows an example of the input device which becomes 2nd Embodiment The figure which shows the example of a switch definition of the input device which becomes 2nd Embodiment The figure which shows the switch definition of the input device of Example 1. The figure which shows the switch structure of the input device of the comparative example 1. The figure which shows the switch definition of the input device of Example 2. The figure which shows the switch structure of the input device of the comparative example 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Switch electrode 2 Switch 3 Capacitance / electrical resistance detection means 4 Switch recognition means 5, 6, 9 Analog input part 7, 8 Digital input part 10, 11, 12, 13 Switch electrode 14 Switch 15 Capacitance detection Means 16 Switch recognition means 17, 18 Analog input unit 19, 20 Digital input unit 21, 25 Analog input unit 22, 23, 24, 26, 27, 28 Digital input unit 29, 30, 31, 32, 33 Switch electrode 34, 35, 41 Analog input section 36, 37, 38, 39, 40, 41, 42, 43 Digital input section

Claims (1)

Detects changes in capacitance caused by the proximity and contact of a plurality of switch electrodes formed on the back surface of an insulating base material so that they do not come into electrical contact with each other and the surface of the insulating base material. And detecting the proximity and contact of a conductor such as the finger to the surface of the insulating base based on the detected amount of change in capacitance, and among the plurality of switch electrodes An analog input unit that outputs a position where a conductor such as a finger is in close proximity, assuming at least a plurality of adjacent switch electrodes as a one-dimensional numerical input unit, and the same switch electrode At least a plurality of analog input units that are shared and a digital input unit that outputs the on / off states of the plurality of switch electrodes, in the case of a plurality, at least the analog input unit and the digital input unit are mutually The position is set based on the setting of the analog input unit and the digital input unit which are different from each other at two proximity levels, that is, the near proximity and the near proximity, and the output of the on / off state is performed. When the electrical conductor such as the above maintains the far proximity level for a predetermined time, the output based on the setting of the far proximity level is performed, and at least a plurality of analog input units sharing the same switch electrode A switch that outputs a position after a conductor such as a finger moves to a switch electrode that is not shared by the plurality of analog input sections when a conductor first approaches and contacts the shared switch electrode. An input device comprising recognition means.

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