Input determination device and input determination method

Abstract

To provide an input determination device with excellent operability and an input determination method.SOLUTION: An input determination device includes: a coordinate detection part configured to detect coordinates of a touch operation that a user performs on an operating surface when operating an operating part through the operating surface; a pressing force detection part configured to detect a pressing force of the touch operation; and a determination part configured to determine whether the operating part is ON or OFF based on the pressing force detected in the pressing force detection part. After determining that the operating part is turned off from ON, the determination part detects a minimum value of the pressing force, and determines that the operating part is turned On from OFF if, after detecting the minimum value, the pressing force exceeds a predetermined threshold that is set based on the minimum value and that is greater than the minimum value.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an input determination device and an input determination method.

Background Art

[0002] Conventionally, there has been an electronic device including an operation unit that receives an operator's input, a contact detection unit that detects contact with the operation unit, a piezoelectric element that detects a change in the pressing load on the operation unit, and a control unit that executes a first process when the piezoelectric element detects a change in a first pressing load. When the piezoelectric element detects a change in a second pressing load and the contact detection unit continuously detects the contact between the detection of the first pressing load and the detection of the second pressing load, the control unit executes a second process. The amount of change in the second pressing load is less than or equal to the amount of change in the first pressing load. The input of the first pressing load is a so-called half-press, and the input of the second pressing load is a so-called full-press (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, there is an input method in which, instead of input methods with significantly different pressing loads such as half-press and full-press, for example, an operation of selecting an operation unit is performed in a first operation input, and the content selected in the first time is confirmed by performing a second operation input with an operation load equivalent to the first time. That is, there is an input method in which an operation input is performed once and then the operation input is performed again.

[0005] In this type of input method, if the threshold for determining whether the device is off after being turned on by the first input is the same as the threshold for determining whether it is on by the first input, the determination of whether it is off will be delayed because it will wait for the pressing force of the first input to decrease. When the determination of whether it is off is delayed, the operability will be poor.

[0006] Therefore, the objective is to provide an input determination device and an input determination method with good operability. [Means for solving the problem]

[0007] An input determination device according to an embodiment of the present invention includes a coordinate detection unit that detects the coordinates of a user's touch operation on the operating surface of the operating unit through the operating surface, a pressing force detection unit that detects the pressing force of the touch operation, and a determination unit that determines whether the operating unit is on or off based on the pressing force detected by the pressing force detection unit. The determination unit detects a minimum value of the pressing force after determining that the operating unit has changed from an on state to an off state, and after detecting the minimum value, determines that the operating unit has changed from an off state to an on state if the pressing force exceeds a predetermined threshold value set based on the minimum value and higher than the minimum value. [Effects of the Invention]

[0008] This invention provides an input determination device and an input determination method that offer excellent operability. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows the electronic device 100 of the embodiment. [Figure 2] This figure shows an example of the relationship between the pressing force of a touch operation performed on the operating surface 101A and a threshold value that the pressing determination unit 143 uses to determine whether the operating unit is on or off. [Figure 3] This diagram shows a flowchart illustrating the process executed by the press detection unit 143. [Modes for carrying out the invention]

[0010] The following describes embodiments to which the input determination device and input determination method of the present invention are applied.

[0011] <Embodiment> Figure 1 shows an electronic device 100 of an embodiment. The electronic device 100 includes a housing 101, a touch panel 110, a display panel 120, a pressing force detection unit 130, and a control device 140. The touch panel 110 is an example of a coordinate detection unit, and the display panel 120 is an example of a display unit.

[0012] The portion of the electronic device 100 excluding the housing 101 and the display panel 120 constitutes the input determination device 100A of this embodiment. For this reason, the touch panel 110, the display panel 120, the pressing force detection unit 130, and the control device 140 are indicated by the reference numeral 100A in parentheses. The input determination device 100A includes the touch panel 110, the display panel 120, the pressing force detection unit 130, and the control device 140. Furthermore, the method executed by the input determination device 100A is the input determination method of this embodiment. Note that the input determination device 100A may also include the housing 101.

[0013] The following explains the XYZ coordinate system. The directions parallel to the X-axis (X direction), the directions parallel to the Y-axis (Y direction), and the directions parallel to the Z-axis (Z direction) are mutually orthogonal. Also, for the sake of explanation, the -Z direction may be referred to as the lower side or bottom, and the +Z direction as the upper side or top, but this does not represent a universal up-and-down relationship. Furthermore, a planar view refers to viewing from the XY plane. Also, in the following, the length, width, thickness, etc. of each part may be exaggerated to make the structure easier to understand.

[0014] The housing 101 has an operating surface 101A and houses a touch panel 110, a display panel 120, a pressing force detection unit 130, and a control device 140. The housing 101 is made of resin, for example, and the operating surface 101A is the surface of a transparent plate located above the touch panel 110. The transparent plate is made of glass or resin, for example.

[0015] Figure 1 exaggerates the thickness of the housing 101 in the Z direction. The operating surface 101A is parallel to the XY plane. The touch panel 110, display panel 120, and force detection unit 130 are arranged in this order, starting downwards from the operating surface 101A, as an example. However, the order in which the touch panel 110, display panel 120, and force detection unit 130 are arranged is not limited to this order.

[0016] As an example, the electronic device 100 detects the coordinates of a touch operation performed by the user on the operating surface 101A using the touch panel 110, and detects the pressing force of the touch operation using the pressing force detection unit 130. The control device 140 accepts touch operations to the operation section displayed on the display panel 120 via a GUI (Graphical User Interface) according to the coordinates detected by the touch panel 110 and the pressing force detected by the pressing force detection unit 130, and controls the display on the display panel 120 according to the operation content. A touch operation is an operation input performed by the user by touching the operating surface 101A with their fingertip FT, and is an operation input in which the user operates the operation section through the operating surface 101A. In addition, the control device 140 may control the display on the display panel 120 according to the operation content and may also output control signals to control the controlled device that is controlled using the electronic device 100 as the user's input unit.

[0017] The electronic device 100 can be mounted on a vehicle, for example, and is a device that can be used as an HMI (Human Machine Interface). In this case, the devices to be controlled may be various devices mounted on the vehicle, such as a navigation system, audio system, air conditioner, etc. The control signals output by the control device 140 are, for example, signals for operating these devices.

[0018] The touch panel 110 is, for example, a capacitive touch panel, and detects coordinates representing the position of the fingertips FT of the user's hand touching the operation surface 101A. Here, as an example, the case where the user touches the operation surface 101A with the fingertip FT to perform an operation input will be described. Note that the touch panel 110 may be other than capacitive type, for example, a resistive film type.

[0019] The display panel 120 can use, for example, a liquid crystal display panel, an organic EL (Electroluminescence) display panel, or the like. The display panel 120 can display images of operation units of various devices of the vehicle described above. The image of the operation unit is, for example, a GUI image representing a switch for volume operation, a switch for selecting a song, etc. when the control target is audio.

[0020] The pressing force detection unit 130 detects the pressing force of the touch operation performed on the operation surface 101A. The pressing force is the pressing load in the downward direction of the touch operation. As the pressing force detection unit 130, for example, a sensor using a piezo element, or a sensor capable of detecting displacement can be used. Note that the pressing force detection unit 130 may be a processing unit that converts the area of the touch operation detected by the touch panel 110 into a pressing force. The pressing force detection unit 130 is larger than the touch panel 110 in plan view, and the region 130A capable of detecting the pressing force is larger than the region 110A capable of detecting the touch operation by the touch panel 110 in plan view, and includes the region 110A. This is to enable detection of the pressing force of the touch operation performed at the end of the touch panel 110.

[0021] The control device 140 includes a position determination unit 141, a pressing force acquisition unit 142, a pressing determination unit 143, an HMI processing unit 144, and a memory 145. The pressing determination unit 143 is an example of a determination unit. The control device 140 is realized by a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an HDD (Hard Disk Drive), an input / output interface, and an internal bus, etc.

[0022] The position determination unit 141, the pressing force acquisition unit 142, the pressing determination unit 143, and the HMI processing unit 144 show the functions (functions) of the program executed by the control device 140 as functional blocks. The memory 145 functionally represents the memory of the control device 140.

[0023] The position determination unit 141 applies voltages in sequence to a plurality of electrodes extending in the X direction and a plurality of electrodes extending in the Y direction of the touch panel 110, detects the capacitance at the intersections of the plurality of electrodes extending in the X direction and the plurality of electrodes extending in the Y direction, and determines the position (coordinates) where the touch operation was performed.

[0024] The pressing force acquisition unit 142 acquires the pressing force detected by the pressing force detection unit 130, performs digital conversion processing and the like, and outputs it to the pressing determination unit 143.

[0025] The pressing determination unit 143 compares the data representing the pressing force output from the pressing force acquisition unit 142 with a threshold value, and determines whether the operation unit has been turned on or off by the pressing due to the touch operation. The processing of the pressing determination unit 143 will be described later using FIG. 2. [[ID=!16]]

[0026] The HMI processing unit 144 controls the display of the display panel 120 according to the position where the touch operation determined by the position determination unit 141 was performed and the determination result of the pressing determination unit 143. When the operation unit is turned on for the first time according to the determination result of the pressing determination unit 143, the HMI processing unit 144 sets the state in which the operation unit is selected, and when it is turned on for the second time, it sets the state in which the selection is confirmed.

[0027] The memory 145 stores programs, data, and the like necessary for the position determination unit 141, the pressing force acquisition unit 142, the pressing determination unit 143, and the HMI processing unit 144 to perform processing, as well as data generated by the processing.

[0028] Figure 2 shows an example of the relationship between the pressing force of a touch operation performed on the operating surface 101A and the threshold value used by the press detection unit 143 to determine whether the operating surface is on or off. In Figure 2, the horizontal axis is the time axis t. Below the horizontal axis is the determination result (on, off) of the press detection unit 143. In addition, the vertical axis of Figure 2 shows the first threshold TH1, the second threshold TH2, a predetermined threshold THD, as well as the threshold TH0, the peak value PK, and the bottom value BTM.

[0029] The first threshold TH1 is the threshold used when the operation unit switches from the off state to the on state. The press detection unit 143 determines that the operation unit has turned on when the pressing force exceeds the first threshold TH1 while the operation unit is in the off state. This is when the operation unit is turned on for the first time by a touch operation. The first threshold TH1 is used, for example, when a user presses the operation surface 101A with a touch operation to select an operation unit. The press detection unit 143 determines that the operation unit has turned on because the pressing force exceeds the first threshold TH1, and the operation unit is selected. Even if the operation unit turns off after being turned on for the first time, the HMI processing unit 144 maintains the selected state of the operation unit as long as the pressing force is greater than the first threshold TH1.

[0030] The peak value PK is the peak value of the pressing force detected by the press detection unit 143 after the operating unit switches from the off state to the on state. The press detection unit 143 detects the peak value (maximum value) of the pressing force by monitoring the pressing force after the operating unit switches from the off state to the on state. The press detection unit 143 stores the detected peak value PK in the memory 145.

[0031] The second threshold TH2 is a threshold used to determine when the operating part switches from on to off when the pressing force decreases from the peak value PK while the operating part is on. The second threshold TH2 is set by the pressing determination unit 143 to a predetermined percentage (expressed as a percentage less than 100%) of the peak value PK. As an example, the predetermined percentage is set to 70% to 85%. The pressing determination unit 143 determines that the operating part has switched from on to off when the pressing force decreases from the peak value PK to below the second threshold TH2 while the operating part is on.

[0032] The bottom value BTM is the minimum value of the pressing force when the operating unit is ON and the pressing force decreases from the peak value PK to below the second threshold TH2, causing the operating unit to turn OFF. This value is detected within a predetermined time after the pressing force falls below the second threshold TH2. The limitation of a predetermined time is imposed because the second ON, performed to confirm the selection of the operating unit after the first ON, is expected to occur relatively soon after the first ON. The bottom value BTM of the pressing force is the minimum value that occurs when the user selects an operating unit, reduces the pressing force once, and then presses the operating unit again to confirm the selection. The bottom value BTM is below the second threshold TH2 and greater than the first threshold TH1. This is because the HMI processing unit 144 turns off the selection of the operating unit when the pressing force falls below the first threshold TH1. The bottom value BTM is detected by the press determination unit 143 and stored in the memory 145.

[0033] The predetermined threshold THD is the threshold used when the operating unit switches back from off to on after the operating unit is turned on, the pressing force decreases from the peak value PK to below the second threshold TH2, the operating unit turns off, and then increases again after reaching the bottom value BTM. This occurs when the operating unit turns on for the second time due to a touch operation after the first time it is turned on. The predetermined threshold THD is a value set by the press determination unit 143 based on the bottom value BTM, and is, for example, the value obtained by adding a predetermined percentage of the bottom value BTM to the bottom value BTM, or the value obtained by adding a threshold (an example of a third threshold) to the bottom value BTM. The predetermined percentage can be set to, for example, about 40% to 60%. The threshold to be added to the bottom value BTM can be set to, for example, about 40% to 60% of the bottom value BTM, or it can be a predetermined real value.

[0034] The threshold TH0 is used to determine whether a touch operation is being performed on the operating surface 101A. Here, the determination of whether a touch operation is being performed is assumed to be performed by the press detection unit 143 as an example. Note that the threshold TH0 may be, for example, about half of the first threshold TH1.

[0035] As shown in Figure 2, when the pressing force rises at time t0 and exceeds the first threshold TH1 at time t1, the pressing determination unit 143 determines that the button has switched from off to on. As the pressing force continues to increase, the pressing determination unit 143 continues to monitor the pressing force and detects the peak value PK at time t2. When the pressing determination unit 143 detects the peak value PK, it calculates the second threshold TH2.

[0036] From time t2 onward, the pressing force decreases, and when it falls below the second threshold TH2 at time t3, the pressing determination unit 143 determines that it has switched from on to off. The pressing force continues to decrease, and the pressing determination unit 143 continues to monitor the pressing force, detecting the bottom value BTM at time t4. Upon detecting the bottom value BTM, the pressing determination unit 143 calculates a predetermined threshold THD.

[0037] The pressing force increases again after reaching its bottom value BTM, and when it exceeds a predetermined threshold THD at time t5, the pressing determination unit 143 determines that the operation unit has turned from off to on. The pressing determination unit 143 determines that the operation unit has turned from off to on because, after being turned on at time t1 and turned off at time t3, the pressing force exceeded a predetermined threshold THD set by the pressing determination unit 143 based on the bottom value BTM without falling below the first threshold TH1. This is the second time the unit is turned on. Since the operation unit is turned on again while the selection of the operation unit is maintained, the operation of the selected operation unit is confirmed.

[0038] Figure 3 is a flowchart showing the process executed by the press detection unit 143. The process shown in the flowchart of Figure 3 is the process according to the input detection method of the embodiment.

[0039] When processing starts, the press detection unit 143 determines whether the pressing force is greater than the first threshold TH1 (step S1). If the press detection unit 143 determines that the pressing force is not greater than the first threshold TH1 (S1: NO), it repeatedly executes the process in step S1 until it determines that the pressing force is greater than the first threshold TH1 (S1: YES).

[0040] The press detection unit 143 determines that the operating unit has turned from off to on when it determines that the pressing force is greater than the first threshold TH1 (S1: YES) (step S2). This is the first on. Upon this first on, the HMI processing unit 144 sets the operating unit to a selected state.

[0041] The press detection unit 143 starts detecting the peak value PK of the pressing force (step S3). Step S3 is a subroutine process in which the press detection unit 143 detects the peak value (maximum value) of the pressing force by monitoring the pressing force after the operating unit switches from the off state to the on state. The press detection unit 143 then stores the detected peak value PK in the memory 145.

[0042] When the press detection unit 143 detects the peak value PK of the press force, it determines whether the press force is less than or equal to the second threshold TH2 (step S4). The press detection unit 143 repeatedly executes the process in step S4 until the press force is less than or equal to the second threshold TH2.

[0043] When the press detection unit 143 determines that the pressing force is less than or equal to the second threshold TH2 (S4: YES), it determines that the operation unit has turned from ON to OFF (step S5). At this time, the HMI processing unit 144 holds the operation unit in the selected state.

[0044] The press detection unit 143 starts detecting the bottom value BTM (step S6). Step S6 is a subroutine process in which the press detection unit 143 detects the bottom value BTM of the press force by monitoring the press force.

[0045] The pressing determination unit 143 determines whether the pressing force is greater than a predetermined threshold THD (step S7).

[0046] If the press detection unit 143 determines in step S7 that the pressing force is greater than a predetermined threshold THD (S7: YES), it determines that the button has been turned on (step S8). Since this is the second time the button has been turned on, the HMI processing unit 144 confirms the selection of the control unit. After completing the processing in step S8, the flow returns to step S3. This is to determine the operation after the second time the button has been turned on.

[0047] Furthermore, if the press detection unit 143 determines that the pressing force is not greater than a predetermined threshold THD (S7: NO), it determines whether the pressing force is less than or equal to the first threshold TH1 (step S9). This process is provided to determine whether the pressing force is less than or equal to the first threshold TH1 because there may be cases where the pressing force is less than or equal to the predetermined threshold THD and the operation to turn it on a second time is not performed.

[0048] The press detection unit 143 determines that the operation unit has been turned off when it determines that the pressing force is less than or equal to the first threshold TH1 (S9: YES) (step S10). As a result, the HMI processing unit 144 sets the state to one where the press operation is not selected. With this, the series of processes is completed (end).

[0049] Furthermore, if the press determination unit 143 determines in step S9 that the pressing force is not less than or equal to the first threshold TH1 (S9: NO), it returns the flow to step S7. This is to determine whether the pressing force is greater than a predetermined threshold THD.

[0050] As described above, in the electronic device 100 and the input detection device 100A, when the pressing force exceeds the first threshold TH1, the operating unit turns on for the first time. While the operating unit is on, the pressing force decreases from the peak value PK to the second threshold TH2 or less, and the operating unit turns off. When it hits the bottom value BTM and exceeds a predetermined threshold THD, the operating unit turns on for the second time. Therefore, the second turn can be detected early.

[0051] Therefore, we can provide an input determination device 100A and electronic device 100 with good operability, as well as an input determination method. As a result, the HMI processing unit 144 can quickly determine the selection of the operation unit according to the on / off determination result by the press determination unit 143 and the position where the touch operation was performed, as determined by the position determination unit 141.

[0052] Furthermore, the press detection unit 143 determines that the device has turned on when the pressing force exceeds the first threshold TH1 while it is in the off state, and determines that it has turned off when the pressing force exceeds the first threshold TH1 and then falls below the second threshold TH2. After determining that it has turned off, it detects the bottom value BTM of the pressing force. This allows it to detect the lowest value BTM at which the pressing force decreases after the first time the device is turned on and increases again for the second time the device is turned on.

[0053] Furthermore, since the bottom value BTM is greater than the first threshold TH1 and less than the second threshold TH2, the second ON state can be determined at an earlier stage.

[0054] Furthermore, the press detection unit 143 determines that the device has turned from off to on when the pressing force exceeds the first threshold TH1, then becomes less than or equal to the second threshold TH2, and then detects the bottom value BTM of the pressing force without it falling below the first threshold TH1, and the pressing force exceeds a predetermined threshold THD. Therefore, when an operation is performed to turn the device on a second time, following the first turn-on, the unit can determine that the device has turned on a second time.

[0055] Furthermore, since the predetermined threshold THD is a value obtained by multiplying the bottom value BTM by a predetermined ratio, or by adding a threshold to the bottom value BTM, a predetermined threshold THD for determining the second ON can be generated according to the detected bottom value BTM, and the second ON can be executed earlier depending on the pressing force. Therefore, it is possible to provide an input determination device 100A and electronic device 100, and an input determination method with better operability.

[0056] Although exemplary embodiments of the present invention, including an input determination device and an input determination method, have been described above, the present invention is not limited to the specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of symbols]

[0057] 100 Electronic equipment 101A Operation surface 110 Touch Panel 120 Display Panels 130 Pressing force detection unit 140 Control device 141 Position determination section 142 Pressing force acquisition unit 143 Press detection unit 144 HMI Processing Unit 145 memory

Claims

1. A coordinate detection unit that detects the coordinates of a user's touch operation on the operating surface, A pressing force detection unit that detects the pressing force of the touch operation, A determination unit determines whether the operating unit is on or off based on the pressing force detected by the pressing force detection unit. Includes, The determination unit, This determines two consecutive ON signals after the aforementioned touch operation is performed. After determining that the operating unit has turned off from the first ON state, the minimum value of the pressing force is detected. After detecting the minimum value, if the pressing force exceeds a predetermined threshold set based on the minimum value and higher than the minimum value, it is determined that the operating unit has turned from off to on for the second time. The touch operation that causes the operation unit to enter the first ON state is a selection operation, and the touch operation that causes the operation unit to enter the second ON state is a confirmation operation. The determination unit, When the operating unit is in the OFF state and the pressing force exceeds the first threshold, it is determined that the unit has been turned ON for the first time. When the pressing force exceeds the first threshold and then falls below a second threshold that is higher than the first threshold and a predetermined percentage of the peak value of the pressing force, it is determined that the operating unit has switched from the first on state to the off state. The operating unit detects the minimum value of the pressing force after it has determined that it has switched from the first ON state to the OFF state. Input detection device.

2. A coordinate detection unit that detects the coordinates of a user's touch operation on the operating surface, A pressing force detection unit that detects the pressing force of the touch operation, A determination unit determines whether the operating unit is on or off based on the pressing force detected by the pressing force detection unit. Includes, The determination unit, This determines two consecutive ON signals after the aforementioned touch operation is performed. After determining that the operating unit has turned off from the first ON state, the minimum value of the pressing force is detected. After detecting the minimum value, if the pressing force exceeds a predetermined threshold set based on the minimum value and higher than the minimum value, it is determined that the operating unit has turned from off to on for the second time. When the operating unit is in the OFF state and the pressing force exceeds the first threshold, it is determined that the unit has been turned ON for the first time. When the pressing force exceeds the first threshold and then falls below a second threshold that is higher than the first threshold and a predetermined percentage of the peak value of the pressing force, it is determined that the operating unit has switched from the first on state to the off state. After determining that the operating unit has switched from the first ON state to the OFF state, the minimum value of the pressing force is detected. The minimum value is detected within a predetermined time after the pressing force falls below the second threshold. Input detection device.

3. The input determination device according to claim 1 or 2, wherein the minimum value is less than or equal to the second threshold and greater than the first threshold.

4. The input determination device according to any one of claims 1 to 3, wherein the determination unit determines that the pressing force has gone from off to the second on when the pressing force exceeds a predetermined threshold, then becomes less than or equal to the second threshold, and then detects a minimum value of the pressing force without it falling below the first threshold, and the pressing force exceeds the predetermined threshold.

5. The input determination device according to any one of claims 1 to 3, wherein the predetermined threshold is a value obtained by adding a predetermined percentage of the minimum value to the minimum value, or a value obtained by adding a third threshold to the minimum value.

6. A coordinate detection unit that detects the coordinates of a user's touch operation on the operating surface, A pressing force detection unit that detects the pressing force of the touch operation, A determination unit determines whether the operating unit is on or off based on the pressing force detected by the pressing force detection unit. An input determination method in an input determination device including, This determines two consecutive ON signals after the aforementioned touch operation is performed. When the operating unit is in the OFF state and the pressing force exceeds the first threshold, it is determined that the unit has been turned ON for the first time. When the pressing force exceeds the first threshold and then falls below a second threshold that is higher than the first threshold and a predetermined percentage of the peak value of the pressing force, it is determined that the operating unit has switched from the first on state to the off state. After determining that the operating unit has switched from the first ON state to the OFF state, the minimum value of the pressing force is detected. After detecting the minimum value, if the pressing force exceeds a predetermined threshold set based on the minimum value and higher than the minimum value, it is determined that the operating unit has turned from off to on for the second time. The touch operation that causes the operation unit to enter the first ON state is a selection operation, and the touch operation that causes the operation unit to enter the second ON state is a confirmation operation. Input detection method.

7. A coordinate detection unit that detects the coordinates of a user's touch operation on the operating surface, A pressing force detection unit that detects the pressing force of the touch operation, A determination unit determines whether the operating unit is on or off based on the pressing force detected by the pressing force detection unit. An input determination method in an input determination device including, This determines two consecutive ON signals after the aforementioned touch operation is performed. When the operating unit is in the OFF state and the pressing force exceeds the first threshold, it is determined that the unit has been turned ON for the first time. When the pressing force exceeds the first threshold and then falls below a second threshold that is higher than the first threshold and a predetermined percentage of the peak value of the pressing force, it is determined that the operating unit has switched from the first on state to the off state. A minimum value is detected within a predetermined time after the pressing force falls below the second threshold. After detecting the minimum value, if the pressing force exceeds a predetermined threshold set based on the minimum value and higher than the minimum value, it is determined that the operating unit has turned from off to on for the second time. Input detection method.

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