Input device

The present invention relates to an input device including an input unit that receives an input by pressing.

In recent years, in information devices, home appliances, and the like, as an input unit for receiving an input operation by a user, an input device including a plate-shaped input unit for receiving an input by pressing a touch panel, a touch switch, or the like is widely used. There are various methods such as a resistive film method and a capacitance method in such an input unit, but all of them accept input by pressing with a finger or a stylus pen, and the input unit itself is pressed. However, it does not displace like a push button switch.

For this reason, the operator cannot obtain feedback when the input by pressing is received. Therefore, for example, in an input device provided with a touch panel, an input error due to an erroneous operation such as pressing the same position many times may occur. It is likely to occur and may cause stress on the operator.

As a device that can prevent such an input error, for example, the display color of an input object such as an input button that receives a pressing input and makes a sound, or an image is displayed on the display unit corresponding to the pressing area. It is known that the input operation can be confirmed by hearing or sight by changing the display mode such as changing the display mode.

However, in the case of a feedback method that works on hearing, it is difficult to confirm in a noisy environment, and if the device used is in a silent state in a manner mode or the like, it cannot be dealt with. Also, in the case of the feedback method that works on the visual sense, if the size of the input object displayed on the display is small, the input object is hidden under the finger and the change in the display mode is confirmed, especially in the case of finger input. It may not be possible.

In addition, a feedback method has been proposed in which the touch panel vibrates when the touch panel receives an input, regardless of hearing or sight, to generate a tactile sensation at the fingertips of the operator (see, for example, Patent Documents 1 and 2). ).

<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2003-288158</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2008-130055</text></patcit>

<p> However, the techniques disclosed in Patent Documents 1 and 2 simply generate a tactile sensation due to vibration at the fingertips of the operator. That is, by vibrating the touch panel, the fingertips of the operator who is in contact with the touch panel are presented with a tactile sensation such as "blu-blu". For example, a "click" felt when a push button switch having a metal dome is operated. It does not present a realistic click feel.</p><p> Therefore, for example, an input key of a mobile terminal such as a mobile phone, an input key of an information device such as a calculator or a ticket vending machine, an input key of an operation unit in a home electric appliance such as a microwave oven or a television is configured by a touch panel, and the touch panel is used. When the above feedback technique is applied, the operator feels uncomfortable.</p><p> Therefore, an object of the present invention made in view of such a point is to provide an input device capable of presenting a realistic click tactile sensation similar to that when an operator operates a push button switch when the operator operates a press-type input unit. To do.</p>

<p> The invention of the input device according to claim 1 that achieves the above object An input unit that accepts input by pressing and A load detection unit that detects the pressing load on the input unit, and a load detection unit. A vibrating part that vibrates the input part and When the pressing load detected by the load detecting unit meets a predetermined criterion for accepting input to the input unit, the pressing object pressing the input unit exhibits a click tactile sensation. After controlling the drive of the vibrating unit and receiving the input to the input unit, when the pressing load detected by the load detecting unit satisfies a predetermined standard, a click tactile sensation is exhibited to the pressed object. A control unit that controls the drive of the vibrating unit, and It is characterized by having.</p>

<p> According to the present invention, when the pressing load on the input unit meets a predetermined standard for accepting an input, the input unit is vibrated, and then, when the pressing load on the input unit meets a predetermined standard, the input is input. Since the part is vibrated, it is possible to present the operator with a realistic click tactile sensation similar to that when the push button switch is operated.</p>

First, prior to the description of the embodiment of the present invention, the principle of the click tactile sensation presentation method by the input device according to the present invention will be described.

The elements that humans feel as tactile sensations are the pressure nerves that feel the tactile sensation such as hardness and softness due to the load transmitted to the bones and muscles when touching the object, and the vibration transmitted to the skin surface when touching the object. There is a tactile nerve that feels the touch of things. That is, the pressure sense detects the load, and the tactile sense detects the vibration. In general, the tactile sensation is a sensation in which a pressure sensation and a tactile sensation are combined. Therefore, if the stimuli to the "pressure" and "tactile" when the push button switch is operated are reproduced in the same manner on the touch panel, for example, it is possible to present the operator with a click tactile sensation.

On the other hand, as push button switches used in information devices and home appliances, for example, metal dome switches, emboss switches, rubber switches, tactile switches and the like are widely known. The load characteristics of these general pushbutton switches generally have the characteristics shown in FIG. 1, although the stroke of the pushbutton and the applied load (pressing force) differ depending on the type of switch.

In the load characteristics at the time of pressing in FIG. 1, the period from point A to point B is a period in which the load increases almost in proportion to the pressing of the push button from the start of pressing. The period from point B to point C is a period in which a convex elastic member such as a metal dome buckles due to the push of a push button and the load decreases sharply. The period from point C to point D is the period in which the contacts of the switch are closed and the load increases in proportion to pushing.

In addition, the load characteristics at the time of release of the push button have some hysteresis, but follow the change opposite to that at the time of pressing. That is, the period from the point D to the point E is the period in which the load decreases almost proportionally from the start of the release, and the contact of the switch is maintained in the closed state. The period from point E to point F is the period in which the elastic member returns from the buckling state to the convex shape by the release of the push button and the load increases sharply, and the contact point of the switch is opened at the start of this period. The period from point F to point G is the period from the return of the elastic member to the release of the push button, which is the period in which the load decreases almost proportionally.

In the load characteristics shown in FIG. 1, the maximum stroke of the push button is, for example, 1 mm or less in the case of a metal dome switch, an emboss switch, and a tactile switch, and 3 mm or less even in the case of a rubber switch. .. The load at point B is, for example, about 1N to about 6N in the case of a metal dome switch, an emboss switch, and a tactile switch, and is, for example, about 0.5N in the case of a rubber switch. Then, no matter which push button switch is operated, the operator can obtain a click tactile sensation.

Therefore, the present inventors have investigated how the pushbutton switch moves to obtain the click tactile sensation produced by the "pressure sensation" and the "tactile sensation". First, it was examined whether the click tactile sensation was due to a stroke change or a pressing load change.

FIG. 2 is a diagram showing sensory evaluation results showing how the operator feels when various pushbutton switches having different pressing loads are operated. The horizontal axis indicates the actual pressing load, and the vertical axis indicates whether the pushbutton switch felt heavy or light on a scale of 7 points. The subjects are five people who are accustomed to using mobile terminals. As is clear from FIG. 2, it can be seen that the pushbutton switch having a high pressing load can be recognized as heavy and the pushbutton switch having a low pressing load can be recognized as light.

FIG. 3 is a diagram showing sensory evaluation results showing how the operator feels when operating various pushbutton switches having different strokes. The horizontal axis shows the actual stroke, and the vertical axis shows whether the pushbutton switch felt long or short, with a maximum of 7 points. The subjects are five people who are accustomed to using mobile terminals, as in the case of Fig. 2. As is clear from Fig. 3, it can be seen that long and short strokes cannot be clearly recognized for minute strokes.

From the above sensory evaluation results, it can be seen that a person can recognize the difference in load, but cannot recognize the difference in minute strokes.

Therefore, the present inventors have focused on the change in the pressing load. That is, if the human cannot recognize the difference in stroke, the click load can be changed by changing the pressing load change on a flat surface such as a touch panel, that is, the stimulation to the pressure sensation as shown by the ABC point shown in FIG. I examined whether it could be felt. Therefore, we created an experimental device with a plate that can be displaced in the vertical direction, pressed the plate from point A to point B shown in Fig. 1, and when the load at point B was reached, the plate was instantly moved downward. The load change between BC points was reproduced by displacing a small amount.

As a result, although a "pressing feeling" of "pressing" the push button switch was obtained, a realistic click feeling such as "clicking" obtained when operating the metal dome switch was not obtained. .. In other words, it was found that there are other factors that cannot be determined by the relationship between stroke and load in order to obtain a realistic click feel.

Therefore, the present inventors then focused on not only "pressure sensation" but also "tactile sensation" which is another sensory nerve. Therefore, the present inventors have measured the vibration generated in the push button when the push button is operated in various mobile terminals equipped with an input device having the push button switch of the metal dome switch. As a result, it was found that the push button vibrates at a frequency of 100 Hz to 200 Hz when the push button reaches point B in FIG. 1, that is, when the metal dome starts buckling.

FIG. 4 is a diagram showing an example of the measurement result in that case. The horizontal axis shows the elapsed pressing time, and the vertical axis shows the vibration amplitude. This pushbutton switch vibrates at point B in FIG. 1 as shown by the solid line in FIG. From this, it was found that in the case of this push button switch, a human being receives a vibration stimulus with a period of about 6 ms (about 170 Hz in frequency) for about one cycle when pressed. Further, in this push button switch, when the pressing load reaches the point F in FIG. 1 at the time of release, that is, when the metal dome returns from the buckling state, the push button vibrates as shown by the alternate long and short dash line in FIG. To do. From this, it was found that in the case of this push button switch, a human being receives a vibration stimulus with a period of about 8 ms (about 125 Hz in frequency) for about one cycle at the time of release.

From the above, when pressing a plate-shaped push-type input unit such as a touch panel, the load from point A to point B shown in Fig. 1 does not cause the input unit to vibrate, and the operator voluntarily. If the pressure sensation is stimulated by pressing and the tactile sensation is stimulated by vibrating the input unit at a frequency of 170 Hz for about one cycle at point B in that state, the operator is pressed according to the measurement result shown in FIG. It is possible to present the same click feeling as when the button switch is operated.

Based on the above principle, the input device according to the present invention stimulates the sense of pressure when pressing a plate-shaped pressing type input unit until the pressing load satisfies a predetermined criterion for accepting input to the input unit. When a predetermined criterion is satisfied, the input unit is vibrated with a predetermined drive signal, that is, a constant frequency, a period (wavelength) which is a drive time, a waveform, and an amplitude, to stimulate the sense of touch.

Further, when a human operates a push button switch, a tactile stimulus from the push button switch is given to the finger not only at the time of pressing but also at the time of release, as shown in FIG. Therefore, in the input device according to the present invention, a click tactile sensation (hereinafter, the click tactile sensation at the time of release is also appropriately referred to as a release tactile sensation) is presented to the operator even at the time of release. As a result, the operator is presented with a realistic click tactile sensation similar to that when the push button switch is pressed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 5 is a block diagram showing a schematic configuration of an input device according to the first embodiment of the present invention. This input device includes a display panel 11, a touch panel 12, a load detection unit 13, a vibration unit 14, and a control unit 15 that controls the overall operation. The display panel 11 constitutes a display unit for displaying an input object such as an input button, and is configured by using, for example, a liquid crystal display panel, an organic EL display panel, or the like. The touch panel 12 constitutes an input unit that receives an input by pressing the display panel 11, and is configured by using a known one such as a resistance film method or a capacitance method. The load detection unit 13 detects the pressing load on the touch panel 12, and is configured by using, for example, a strain gauge sensor. Further, the vibrating unit 14 vibrates the touch panel 12, and is configured by using, for example, a piezoelectric vibrating element.

6A and 6B show an example of the mounting structure of the input device shown in FIG. 5, FIG. 6A is a cross-sectional view of a main part, and FIG. 6B is a plan view of the main part. The display panel 11 is stored and held in the housing 21. The touch panel 12 is held on the display panel 11 via an insulator 22 made of an elastic member. In the input device according to the present embodiment, the display panel 11 and the touch panel 12 are rectangular in a plan view, and the touch panel 12 is displaced from the display area A of the display panel 11 shown by a virtual line in FIG. 6 (b). It is held on the display panel 11 via the insulators 22 arranged at the four corners.

Further, the housing 21 is provided with an upper cover 23 so as to cover the surface area of the touch panel 12 outside the display area of the display panel 11, and an insulator 24 made of an elastic member is provided between the upper cover 23 and the touch panel 12. Is arranged.

In the touch panel 12, for example, the front surface, that is, the operation surface is made of a transparent film, the back surface is made of glass, and when the operation surface is pressed, the transparent film on the front surface is slightly bent (distorted) in response to the pressing force. ) Use a structure.

On the transparent film on the surface of the touch panel 12, strain gauge sensors 31 for detecting the load (pressing pressure) applied to the touch panel 12 are provided in the vicinity of each side covered by the upper cover 23 by adhesion or the like. Further, on the glass surface on the back surface of the touch panel 12, piezoelectric vibrators 32 for vibrating the touch panel 12 are provided in the vicinity of the two opposing sides by adhesion or the like. That is, in the input device shown in FIG. 6, the load detecting unit 13 shown in FIG. 5 is configured by using four strain gauge sensors 31, and the vibrating unit 14 is configured by using two piezoelectric vibrators 32. Note that FIG. 6 (b) omits the illustration of the housing 21, the upper cover 23, and the insulator 24 shown in FIG. 6 (a).

FIG. 7 is a flowchart showing the operation of the input device according to the present embodiment. The control unit 15 monitors the input to the touch panel 12 and also monitors the load detected by the load detection unit 13. Then, the input to the touch panel 12 is an input to the input object displayed on the display panel 11, and the pressing load detected by the load detecting unit 13 is increased by the pressing of the touch panel 12, and the input is accepted. When it is detected that the reference is satisfied (step S81), the input to the touch panel 12 at that time is accepted, the vibrating unit 14 is driven by a predetermined drive signal, and the touch panel 12 vibrates in a predetermined vibration pattern set in advance. Let (step S82). As a result, the operator is presented with a click tactile sensation through the finger pressing the touch panel 12 or the pressed object of the stylus pen to recognize that the input operation is completed. The load detection unit 13 detects the load from, for example, the average value of the outputs of the four strain gauge sensors 31. Further, the vibrating unit 14 drives, for example, two piezoelectric vibrators 32 in the same phase.

Here, the predetermined reference detected in step S81 is, for example, the load at point B shown in FIG. Therefore, this predetermined reference may be appropriately set according to the load characteristics when the push button switch to be expressed is pressed. For example, when applied to a mobile terminal, the user can freely set the setting so that the elderly user can set it heavier and the user who frequently emails can set it lighter. Further, a predetermined drive signal for driving the vibrating unit 14 in step S82, that is, a constant frequency, period (wavelength), waveform, and amplitude that stimulate the sense of touch may be appropriately set according to the click tactile sensation to be presented. For example, when exhibiting a click tactile sensation typified by a metal dome switch used in a mobile terminal, as will be described later, when a predetermined load is applied to the touch panel 12, for example, a sine wave having a constant frequency of 170 Hz. The vibrating unit 14 is driven by a drive signal for one cycle consisting of the above, and the touch panel 12 is vibrated by about 15 μm with a predetermined load applied. As a result, it is possible to present the operator with a realistic click tactile sensation.

After that, when the control unit 15 detects that the load detected by the load detection unit 13 satisfies a predetermined standard (step S83), the control unit 15 drives the vibration unit 14 with a predetermined drive signal as in the case of pressing. Then, the touch panel 12 is vibrated in a predetermined vibration pattern set in advance (step S84).

Here, the predetermined reference load detected at the time of release of step S83, that is, after the reception of the pressing input can be set to an arbitrary load equal to or less than the load at the time of pressing detected in step S81. Further, at the time of release of step S84, the drive signal for driving the vibrating unit 14 may be the same as or different from the drive signal at the time of pressing in step S82. For example, the frequency of the drive signal at the time of pressing to receive the input to the touch panel 12 can be 170 Hz, and the frequency of the drive signal at the time of release can be 125 Hz, for example, as shown in FIG.

As described above, the input device according to the present embodiment stimulates the pressure sense until the load applied to the touch panel 12 detected by the load detection unit 13 satisfies a predetermined criterion for accepting the input to the touch panel 12. When a predetermined reference is satisfied, the vibrating unit 14 is driven by a predetermined drive signal to vibrate the touch panel 12 in a predetermined vibration pattern to stimulate the sense of touch. As a result, the operator is presented with a click tactile sensation to recognize that the input operation has been completed. Therefore, the operator can perform the input operation while obtaining the same realistic click feeling as when the push button switch is operated on the touch panel 12, so that the operator does not feel a sense of discomfort. Further, since the input operation can be performed in conjunction with the consciousness that the touch panel 12 is "pressed", it is possible to prevent an input error due to simple pressing.

Further, when a predetermined standard is satisfied at the time of release after receiving the pressing input, the vibrating unit 14 is driven by a predetermined driving signal as in the case of pressing, and the touch panel 12 is set in a predetermined vibration pattern. Since it vibrates with, it is possible to present a release tactile sensation. Therefore, in combination with the click tactile sensation at the time of pressing, the click tactile sensation closer to that of the push button switch can be presented to the operator.

For example, when the reference load for driving the vibrating unit 14 is set to be the same at the time of pressing and at the time of release, if the maximum load at the time of pressing exceeds the reference load, the pressing is performed as shown in FIG. It is possible to present a click tactile sensation at the time and at the time of release. Therefore, it is possible to present the operator with a click feeling closer to that of the push button switch. In addition, in FIG. 8 and other figures, "ka" and "chi" represent the click tactile sensation received by a human.

Further, when the reference load for driving the vibrating portion 14 is set to an arbitrary load lower than that at the time of pressing at the time of release, even if the maximum load at the time of pressing is the reference load at the time of pressing, that is, pressing. Even when the pressed object is turned back with the load of the time reference, as shown in FIG. 9, the click tactile sensation can be exhibited at the time of pressing and at the time of release. As shown in FIG. 8, when the reference load for driving the vibrating portion 14 is set to the same load at the time of pressing and at the time of release, when the maximum load at the time of pressing matches the reference load. , If the vibrating unit 14 is not driven at the time of release, or if the operator tries to hold the pressing load with the reference load, an unexpected release tactile sensation may be presented, which may give the operator a sense of discomfort. To. On the other hand, as shown in FIG. 9, if the reference load for driving the vibrating portion 14 at the time of release is set to an arbitrary load lower than the reference at the time of pressing, the release feel can be reliably presented at the time of release. , The click feeling closer to that of a push button switch can be more reliably presented to the operator.

(Second embodiment) 10 and 11 show an input device according to a second embodiment of the present invention, FIG. 10 is a block diagram showing a schematic configuration, and FIG. 11 is a front view. This input device is mounted on a mobile terminal, for example, and as shown in FIG. 10, includes a touch panel 41 which is an input unit that accepts input by pressing, a position detection unit 42 that detects an input position with respect to the touch panel 41, and the like. Controls the overall operation of the display panel 43 that displays information based on the input position detected by the position detection unit 42, the load detection unit 44 that detects the pressing load on the touch panel 41, and the vibration unit 45 that vibrates the touch panel 41. It has a control unit 46 and a control unit 46.

As shown in FIG. 11, a plurality of input objects 41a such as a numeric keypad are formed on the touch panel 41 by printing or pasting in advance. Each input object 41a is set to have an effective pressing area for receiving input narrower than the formation area of the input object 41a in order to prevent erroneous input due to pressing across a plurality of adjacent input objects 41a. In FIG. 10, the load detection unit 44 and the vibration unit 45 are configured by using a strain gauge sensor and a piezoelectric vibrator, respectively, as in the case of the input device shown in FIG.

The control unit 46 monitors the input to the touch panel 41 and the load detected by the load detection unit 44, respectively, and monitors the input position with respect to the touch panel 41 detected by the position detection unit 42. Then, the position detection unit 42 detects the input position of the effective pressing area of the input object, and the pressing load detected by the load detecting unit 44 increases with the pressing of the touch panel 41 to receive the input. When the condition is satisfied, the vibrating unit 45 is driven by a predetermined drive signal to vibrate the touch panel 41 in a predetermined vibration pattern set in advance.

That is, when the position detection unit 42 detects the input position of the effective pressing area of the input object, the control unit 46 increases the load on the touch panel 41 as in the input device according to the first embodiment. However, when a predetermined standard is satisfied, for example, the vibrating unit 45 is driven by a drive signal for one cycle consisting of a Sin wave having a constant frequency of 170 Hz, and the touch panel 41 is subjected to a predetermined load. Vibrate 15 μm. As a result, the operator is presented with a click tactile sensation to recognize that the input operation has been completed. Further, the control unit 46 receives the input detected by the touch panel 41 and displays the display panel 43 according to the input.

After that, when the control unit 46 detects that the load detected by the load detection unit 44 satisfies the predetermined reference at the time of release, the control unit 46 sets the vibrating unit 45 as in the input device according to the first embodiment. The touch panel 41 is driven by a predetermined drive signal to vibrate in a predetermined vibration pattern set in advance.

Therefore, according to the input device according to the present embodiment, as in the case of the first embodiment, the operator obtains the same realistic click feeling as when the push button switch is operated on the touch panel 41. , You can perform input operations, so you will not feel any discomfort. Further, since the input operation is performed in conjunction with the consciousness of "pressing" the touch panel 41, it is possible to prevent an input error due to a simple pressing.

Further, when a predetermined standard is satisfied at the time of release after receiving the pressing input, the vibrating unit 45 is driven by a predetermined driving signal as in the case of pressing, and the touch panel 41 is set in a predetermined vibration pattern. Since it vibrates with, it is possible to present a release tactile sensation. Therefore, in combination with the click tactile sensation at the time of pressing, the click tactile sensation closer to that of the push button switch can be presented to the operator.

Hereinafter, the sensory evaluation results of the click tactile sensation verified by the present inventors in the input device according to each of the above embodiments will be described.

According to the measurements by the present inventors, the metal dome switch widely used in commercially available mobile terminals varies depending on the model of the terminal, but suddenly when a predetermined load of about 6 N or less, generally 3 N or less is applied. It has a load characteristic that reduces the load. Therefore, the present inventors first performed a sensory evaluation of the click tactile sensation when the vibrating portion 14 was driven only when pressed in the input devices having the configurations shown in FIGS. 5 and 6. In this sensory evaluation, the load of the touch panel 12 that starts driving the vibrating unit 14 when pressed (the load at point B in FIG. 1) was 1.5 N, and the frequency, period (wavelength), and waveform of the drive signal were used as parameters.

Examples of these evaluation results are shown in FIGS. 12 to 15. In FIGS. 12 to 15, the subjects are the same five as those who performed the sensory evaluation in FIGS. 2 and 3. The evaluation items are "feeling like a click touch", "good as a touch touch", and "similar to a mobile terminal". As for the evaluation points, in the evaluation items of "feeling a click touch", "not feeling" is 1 point and "feeling strongly" is 7 points. In the evaluation items of "good to the touch", "bad" is 1 point and "good" is 7 points. In the evaluation items of "similar to mobile terminals", "not similar" is 1 point and "very similar" is 7 points. The evaluation score of each item was the average score of 5 people.

FIG. 12 shows the evaluation results when the frequency is changed. In this sensory evaluation, the period (wavelength) of the drive signal that drives the vibrating unit 14, that is, the drive time is one period, the waveform is a sine wave, and the frequency is changed in the range of 50 Hz to 250 Hz. The amplitude of the drive signal was set to the signal amplitude at which a vibration amplitude of 15 μm can be obtained on the touch panel 12 with a predetermined reference load applied. As a result, as is clear from FIG. 12, when the frequency is 170 Hz, the evaluation is highest, but when it is 140 Hz or higher, it was confirmed that humans can obtain a click tactile sensation similar to that of a mobile terminal.

FIG. 13 shows the evaluation results when the amplitude of the drive signal is changed. In this sensory evaluation, the frequency of the drive signal for driving the drive unit 14 was 170 Hz, the period was one period, and the waveform was a sine wave. Further, the signal amplitude was changed so that the touch panel 12 vibrates with a predetermined amplitude within 1 μm to 35 μm when the touch panel 12 is not pressed and there is no load. Then, under each no-load vibration amplitude condition, the drive unit 14 was driven when a load of 1.5 N was applied to the touch panel 12, and each evaluation item was evaluated. The horizontal axis of FIG. 13 shows the vibration amplitude when a load of 1.5 N is applied, corresponding to the vibration amplitude of the touch panel 12 when no load is applied. As a result, as is clear from FIG. 13, it was confirmed that when a load of 1.5 N is applied, a human can sufficiently feel a click tactile sensation when the vibration amplitude is 15 μm or more. In other words, when a pressing load of 1.5N is applied to the touch panel 12, the touch panel 12 is vibrated at a constant frequency of 170Hz with a vibration amplitude of 15μm or more for only one cycle, and humans feel a click touch. Was confirmed.

FIG. 14 shows the evaluation results when the period (wavelength), which is the driving time, is changed. In this sensory evaluation, the waveform of the drive signal that drives the vibrating unit 14 is a sine wave, the signal amplitude is the amplitude at which the vibration amplitude is about 15 μm when a predetermined reference load is applied to the touch panel 12, and the frequency is 170 Hz. , The period was changed in the range of 1/4 period to 3 periods. In the 1/4 cycle and the 1/2 cycle, the vibration displacement in the touch panel 12 is almost equal to that in the other cycles, that is, the signal amplitude is set so that a vibration amplitude of about 15 μm can be obtained. As a result, as is clear from FIG. 14, the highest evaluation was obtained when the period (wavelength) was one period. In addition, although good results were obtained in 5/4 cycle or less than 1 cycle, it was confirmed that the click feeling of the mobile terminal deviated from 3/2 cycle or more.

FIG. 15 shows the evaluation result when the waveform of the drive signal is changed. In this sensory evaluation, each of the cases where the waveform of the drive signal for driving the vibrating unit 14 was a sine wave, a square wave, and a triangular wave was evaluated. The frequency of each signal was 170 Hz, the signal amplitude was an amplitude at which the vibration amplitude of the touch panel 12 under a predetermined reference load was about 15 μm, and the period was one cycle. As a result, as is clear from Fig. 15, the highest evaluation was obtained in the case of the Sin wave.

Here, the drive signal of the sine wave (input voltage of the drive unit 14) is not limited to one cycle in which the voltage increases and decreases from the phase 0 degree, as shown by the alternate long and short dash line in FIG. Can be a voltage of one cycle from any phase, such as decreasing and increasing. Note that FIG. 16 shows the vibration amplitude waveform (broken line) of the touch panel 12 when the drive unit 14 is driven by the input voltage shown by the alternate long and short dash line, and the vibration of the touch panel 12 when pressed at 1.5 N. It is also shown together with the amplitude waveform (solid line).

From the above evaluation result examples, when the input device having the configuration shown in FIGS. 5 and 6 is applied to the mobile terminal, when a load satisfying a predetermined standard is applied when the touch panel 12 is pressed, for example, the frequency is 140 Hz or higher. If the touch panel 12 is vibrated by about 15 μm or more with a sine wave drive signal of 5/4 cycle or less, preferably 1 cycle, preferably at a constant frequency of 170 Hz, a realistic click tactile sensation can be presented to the operator. It was confirmed that. It was confirmed that the same results could be obtained with the input devices having the configurations shown in FIGS. 10 and 11.

Next, the present inventors performed a sensory evaluation of the click tactile sensation when the vibrating portion 14 was driven only when pressed and when the vibrating portion 14 was driven both when pressed and when released as described above. The results will be described below.

FIG. 17 is a diagram showing an example of the evaluation result in this case. In FIG. 17, the left side shows the evaluation result when the vibrating portion 14 is driven only when pressed, that is, when no release tactile sensation, and the right side shows the evaluation result when driven both when pressed and when released, that is, release. The sensory evaluation result in the case of "feeling to the touch" is shown. The subjects were the same five as those who performed the sensory evaluation in FIGS. 2 and 3. The evaluation items are 4 items, which are the 3 items in FIGS. 12 to 15 plus the item "good as feedback (easy to recognize)". The evaluation points for each item were the average of 5 people, with a maximum of 7 points. In the evaluation items of "good as feedback", "bad" is 1 point and "good" is 7 points. Further, the load of a predetermined reference for driving the vibrating unit 14 is the same at the time of pressing and the time of release, and the drive signal is also the same. Here, the predetermined reference load is 1.5 N. As for the drive signal, the touch panel 12 was vibrated by about 15 μm in a pressed state of 1.5 N, with a Sin wave having a frequency of 170 Hz as one cycle.

As is clear from the evaluation results in FIG. 17, it was confirmed that the touch panel 12 was vibrated at the time of release to exhibit the release tactile sensation, which was more similar to the click tactile sensation of the mobile terminal and had better feedback (recognition). did it. It was confirmed that the same results could be obtained with the input devices having the configurations shown in FIGS. 10 and 11.

(Third embodiment) By the way, for example, in an input device used for a mobile terminal, when inputting a telephone number, an e-mail, or the like, the same input object is continuously input, so-called continuous hitting is frequently performed. In such a case, as shown in FIG. 17, when the touch panel is vibrated with a predetermined vibration pattern not only at the time of pressing but also at the time of release, a predetermined reference load for driving the vibrating part at the time of release is appropriately set. There is a need to.

That is, when a human performs continuous input quickly, in general, the pressing load does not drop to "0" and the next input is started, and the maximum load at the time of pressing varies. At this time, for example, as described in the first embodiment, when a predetermined reference load for driving the vibrating portion 14 is set to be the same at the time of pressing and at the time of release, as shown in FIG. , If the pressing load is returned with the reference load in the middle of repeated hitting input, the vibrating part 14 may not be driven at the time of release, or the tactile sensation may be presented before the consciousness released by the operator. Therefore, it is assumed that the input operation and the tactile sensation do not match, which may give the operator a sense of discomfort. Note that FIG. 18 shows a case where the pressing load of the third input is pulled back by the reference load in the four consecutive inputs.

On the other hand, if the predetermined reference load that drives the vibrating unit 14 at the time of release is set to a value that is too low compared to the load that drives the vibrating unit 14 at the time of pressing, as shown in FIG. If the next input operation is performed without the load returning to the reference at the time of release in the middle of, it is assumed that the tactile sensation may be shifted, which may give the operator a sense of discomfort. Note that FIG. 19 shows a case where the third input is performed before the load at the time of release in the second input reaches the reference at the time of release in the four consecutive hit inputs. Further, if the load of the predetermined reference at the time of release is too low as described above, it takes time to return to the predetermined reference. As a result, the operator does not feel uncomfortable with the tactile sensation presented, and although he / she wants to perform continuous input, it takes time until the next input, and quick continuous input cannot be performed. There is a concern that the operability of the

On the other hand, if the predetermined reference load that drives the vibrating unit 14 at the time of release is set to a value close to the load that drives the vibrating unit 14 at the time of pressing, continuous input becomes possible more quickly, but continuously. If an attempt is made to hold the pressed state during input, it is assumed that an unexpected release tactile sensation may be presented, which may give the operator a sense of discomfort. That is, when the pressing state is held in the middle of continuous input, the operator has a slight load fluctuation even if he / she intends to keep the pressing load constant. Therefore, for example, as shown in FIG. 20, when the load width between the reference at the time of pressing and the reference at the time of release is narrower than the width of the load fluctuation in the above-mentioned hold state, the operator holds the load. Even if you intend, the tactile sensation at the time of release will be presented and you will feel a sense of discomfort.

Therefore, in the third embodiment of the present invention, it is possible to cope with the above-mentioned operability at the time of continuous input and a minute load change in the hold state, and the operator can obtain a realistic click tactile sensation and perform smooth continuous input. In order to enable this, in the input device described in the first embodiment or the second embodiment, a predetermined reference load for driving the vibrating portion at the time of release is applied to a predetermined reference for driving the vibrating portion at the time of pressing. Set the value in the range of 50% to 80% with respect to the load.

Hereinafter, the sensory evaluation results of the click tactile sensation verified by the present inventors in the input device according to the third embodiment will be described.

21 to 23 are diagrams showing an example of the evaluation result in this case. In FIGS. 21 to 23, the subjects are the same five as those who performed the sensory evaluation in FIG. The evaluation items are 5 items, which are the 4 items in FIG. 17 plus the item "easy to hit repeatedly". The evaluation points for each item were the average of 5 people, with a maximum of 7 points. In the evaluation items of "easy to hit repeatedly", "difficult to do" was 1 point and "easy to input continuously" was 7 points. In addition, the drive signal that drives the vibrating part during both pressing and releasing vibrates the touch panel by about 15 μm when a sine wave with a frequency of 170 Hz is used for one cycle and each meets a predetermined standard.

FIG. 21 shows the evaluation results when the predetermined reference at the time of pressing is 1N and the predetermined reference at the time of release is 0N, 0.5N, and 1N. As is clear from FIG. 21, when the predetermined reference load that starts vibration at the time of pressing is 1N, it is the highest among all the evaluation items when the predetermined reference load that starts vibration at the time of release is 0.5N. Evaluation was obtained.

FIG. 22 shows the evaluation results when the predetermined reference at the time of pressing is 2N and the predetermined reference at the time of release is 0N, 0.5N, 1N, 1.5N, 2N. As is clear from FIG. 22, when the predetermined reference load that starts vibration at the time of pressing is 2N, the high evaluation is obtained when the predetermined reference load that starts vibration at the time of release is 1N and 1.5N. Especially in the case of 1.5N, the highest evaluation was obtained in all the evaluation items.

FIG. 23 shows the evaluation results when the predetermined reference at the time of pressing is 3N and the predetermined reference at the time of release is 0N, 0.5N, 1N, 1.5N, 2N, 2.5N, 3N. As is clear from FIG. 23, when the predetermined reference load that starts vibration at the time of pressing is 3N, the evaluation is high when the predetermined reference load that starts vibration at the time of release is 1.5N, 2N and 2.5N. The highest evaluation was obtained in all the evaluation items, especially in the case of 2N.

From the above evaluation result example, if the predetermined reference load for driving the vibrating part at the time of release is set to a value in the range of 50% to 80% with respect to the predetermined reference load for driving the vibrating part at the time of pressing. In continuous input (continuous hitting), it was confirmed that the sequential input and the tactile sensation presentation timing match, and a realistic click tactile sensation without discomfort can be presented. That is, the predetermined reference load at the time of release is made smaller than the predetermined reference load at the time of pressing so as not to give a sense of discomfort, and the predetermined reference load at the time of release is set to the predetermined load at the time of pressing. By setting the load to 50% or more of the standard load of, the operability at the time of continuous input is remarkably improved. Further, by setting the predetermined reference load at the time of release to 80% or less of the predetermined reference load at the time of pressing, it is possible to cope with a minute load change in the hold state at the time of continuous input.

Therefore, for example, when the predetermined reference at the time of pressing is set to 1N, the predetermined reference at the time of release is set to an arbitrary value of 0.5N to 0.8N. Further, when the predetermined reference at the time of pressing is a high load, the range of load fluctuation in the hold state is wider than when the standard is a low load. Even in such a case, if the predetermined reference load at the time of release is set as high as 50% to 80% of the predetermined reference load at the time of pressing, for example, the predetermined reference at the time of pressing is set as high as 6N. Set the prescribed standard at the time of release to 3N to 4.8N. As a result, it is possible to present a realistic click tactile sensation corresponding to continuous input without presenting an unexpected release tactile sensation. These predetermined reference loads at the time of pressing and the predetermined reference load at the time of release may be fixedly set, or may be appropriately selected and set by the user.

The present invention is not limited to the above embodiment, and many modifications or changes can be made. For example, the load detection unit can be configured by using an arbitrary number of strain gauge sensors. Further, the load detection unit is charged according to the input detection method on the touch panel, for example, from the change in the output signal based on the resistance change due to the contact area in the case of the resistance film method, or in the case of the capacitance method. If the load can be detected from the change in the output signal based on the change in capacitance, it can be configured without using the strain gauge sensor. Further, the vibrating part is configured by using an arbitrary number of piezoelectric vibrators, is configured by providing a transparent piezoelectric element on the entire operation surface of the touch panel, or rotates the eccentric motor once in one cycle of the drive signal. It can also be configured or configured.

Further, as shown in FIGS. 5 and 6, when the input device has a display panel, the control unit inverts the display color of the corresponding input object on the display panel when the input by the touch panel is received. It is also possible to control so as to change the display mode such as. Further, the control unit can be configured to change the drive signal for driving the vibrating unit to change the click tactile sensation to be presented according to the input position detected by the touch panel.

Further, the present invention can be effectively applied to an input device in which the input unit functions as one switch. Further, the input device according to the present invention is a multi-step switch such as a two-step switch (pushed in and then pushed in) by sequentially exhibiting a click tactile sensation according to a different reference (load) during pressing of the input portion. It can also exhibit a tactile sensation. As a result, for example, when applied to the release button of a camera, it is possible to present the tactile sensation of focus lock (pressing 1 step) and release (pressing 2 steps). Further, when combined with the display unit, it is possible to change the display of the menu screen or the like in various ways according to the number of steps of pushing. Further, when the tactile sensation of the multi-stage switch is presented in this way, it is also possible to change the drive signal for vibrating the input unit by the vibrating portion at each stage to exhibit a different click tactile sensation at each stage.

Further, in the present invention, when the pressing load detected by the load detecting unit satisfies a predetermined criterion for accepting an input, the vibrating unit is driven, but the pressing load detected by the load detecting unit accepts the input. When the predetermined criteria are satisfied, the pressing load detected by the load detecting unit may reach a predetermined value for accepting the input, or the pressing load detected by the load detecting unit accepts the input. It may be when the value is exceeded, or when a predetermined value for accepting an input is detected by the load detection unit.

Further, when the pressing load detected by the load detecting unit satisfies a predetermined standard, the control unit drives the vibrating unit to vibrate the input unit (touch panel) in a preset predetermined vibration pattern. The predetermined vibration pattern may be the vibration pattern shown by the solid line in FIG. 4 when pressed. Further, the predetermined vibration pattern may be the vibration pattern shown by the alternate long and short dash line in FIG. 4 at the time of release. By vibrating the input unit in this way, it is possible to present the operator with a click tactile sensation (vibration stimulus) similar to that when the push button switch is operated.

<figref num="1">It is a figure which shows the general load characteristic of a push button switch.</figref><figref num="2">It is a figure which shows the sensory evaluation result at the time of operating various pushbutton switches with different pressing loads.</figref><figref num="3">It is a figure which shows the sensory evaluation result at the time of operating various pushbutton switches with different strokes.</figref><figref num="4">It is a figure which shows an example of the measurement result of the vibration generated in the push button when the push button switch is operated.</figref><figref num="5">It is a block diagram which shows the schematic structure of the input device which concerns on 1st Embodiment of this invention.</figref><figref num="6">It is a figure which shows an example of the mounting structure of the input device shown in FIG.</figref><figref num="7">It is a flowchart which shows the operation of the input device shown in FIG.</figref><figref num="8">It is a figure for demonstrating an example of the click tactile sensation presentation when the reference load at the time of pressing and the reference load at the time of release is set to be the same in the input device shown in FIG.</figref><figref num="9">It is a figure for demonstrating an example of the click tactile sensation presentation when the reference load at the time of release is set smaller than the reference load at the time of pressing in the input device shown in FIG.</figref><figref num="10">It is a block diagram which shows the schematic structure of the input device which concerns on 2nd Embodiment of this invention.</figref><figref num="11">It is a front view of the input device shown in FIG.</figref><figref num="12">It is a figure which shows the sensory evaluation result of the click tactile sensation when the frequency of the drive signal which drives the vibrating part shown in FIG. 5 is changed.</figref><figref num="13">It is a figure which shows the sensory evaluation result of the click touch feeling when the vibration amplitude of the touch panel shown in FIG. 5 is changed.</figref><figref num="14">It is a figure which shows the sensory evaluation result of the click tactile sensation when the cycle of the drive signal which drives the vibrating part shown in FIG. 5 is changed.</figref><figref num="15">It is a figure which shows the sensory evaluation result of the click touch feeling when the waveform of the drive signal which drives the vibrating part shown in FIG. 5 is changed.</figref><figref num="16">It is a figure which shows the waveform of the drive signal which drives the vibrating part shown in FIG. 5 and the vibration amplitude waveform of an actual touch panel.</figref><figref num="17">FIG. 5 is a diagram showing an example of the sensory evaluation result of the click tactile sensation by the input device shown in FIG. 5 in comparison with the case without the release tactile sensation.</figref><figref num="18">It is a figure for demonstrating an example of the tactile sensation presentation at the time of continuous input when the reference load at the time of pressing and at the time of release is set to be the same.</figref><figref num="19">It is a figure for demonstrating an example of the tactile sensation presentation at the time of continuous input when the reference load at the time of release is set to the value too low with respect to the reference load at the time of pressing.</figref><figref num="20">It is a figure for demonstrating an example of the tactile sensation presentation at the time of continuous input when the reference load at the time of release is set to the value close to the reference load at the time of pressing.</figref><figref num="21">It is a figure which shows the example of the sensory evaluation result of the tactile sensation when the reference load at the time of pressing is set to 1N in the input device which concerns on 4th Embodiment of this invention.</figref><figref num="22">It is a figure which shows the example of the sensory evaluation result of the tactile sensation when the reference load at the time of pressing is set to 2N in the input device which concerns on 4th Embodiment of this invention.</figref><figref num="23">It is a figure which shows the example of the sensory evaluation result of the tactile sensation when the reference load at the time of pressing is set to 3N in the input device which concerns on 4th Embodiment of this invention.</figref>

Code description

11 Display panel 12 touch panel 13 Load detector 14 Vibrating part 15 Control unit 21 chassis 21 LCD panel 22 Insulator 23 Upper cover 24 Insulator 31 Strain gauge sensor 32 ultrasonic oscillator 41 touch panel 41a Input object 42 Position detector 43 Display panel 44 Load detector 45 Vibrating part 46 Control unit