Capacitive input device and capacitive input method
The capacitive input device uses a multi-threshold determination process to accurately identify the activated touch switch among multiple adjacent switches, addressing the ambiguity in conventional devices by employing a first threshold and additional thresholds for precise detection.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- ALPS ALPINE CO LTD
- Filing Date
- 2022-06-27
- Publication Date
- 2026-06-23
AI Technical Summary
Conventional capacitive touch switch devices struggle to accurately determine which of multiple adjacent touch switches has been activated due to low initial threshold settings, leading to ambiguity in identifying the correct switch.
The capacitive input device employs a determination unit that utilizes a first comparison with a first threshold and subsequent comparisons with multiple thresholds to differentiate between touch switches, including a second and third threshold, to accurately identify the touched switch.
This approach enables precise determination of the touched switch, even in scenarios where adjacent switches exhibit similar capacitance changes, particularly when gloves are worn or multiple switches are activated simultaneously.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a capacitive input device and a capacitive input method.
Background Art
[0002] Conventionally, there has been a capacitive touch switch device including a touch electrode, a touch detection circuit that outputs a touch detection signal indicating the presence or absence of a touch, and a threshold value specifying circuit that supplies a threshold value specifying signal for specifying a threshold value to the touch detection circuit. The threshold value is set low at the stage of receiving a touch operation, and is set high after receiving the touch operation to accelerate the reaction to the touch operation (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, when applying the threshold value specifying circuit of the conventional capacitive touch switch device to a plurality of touch switches arranged adjacent to each other, since the threshold value at the stage of receiving a touch operation is very low, it is determined that touch operations are performed simultaneously on a plurality of touch switches, and it is difficult to determine on which of the plurality of touch switches the touch operation has been performed.
[0005] Therefore, an object is to provide a capacitive input device and a capacitive input method capable of determining on which of a plurality of touch switches a touch operation has been performed.
Means for Solving the Problems
[0006] The capacitive input device according to an embodiment of the present invention includes a plurality of touch switches and a determination unit that determines a touch operation to any one of the plurality of touch switches based on the outputs of the plurality of touch switches. The determination unit performs a first comparison by comparing a first threshold used to determine whether or not a touch operation has occurred with each of the outputs of the plurality of touch switches, and performs a second comparison by comparing an output from the plurality of touch switches that is greater than the first threshold with a plurality of different comparison thresholds that are greater than the first threshold, and determines a touch operation to any one of the plurality of touch switches based on the comparison result obtained in the first comparison or the second comparison. [Effects of the Invention]
[0007] This invention provides a capacitive input device and a capacitive input method capable of determining which of multiple touch switches has been touched. [Brief explanation of the drawing]
[0008] [Figure 1] This figure shows a steering wheel 10 equipped with an operating unit 110 for a capacitive input device according to the embodiment. [Figure 2] This figure shows a capacitive input device 100 according to an embodiment. [Figure 3] This figure shows the capacitance distribution at touch switches 111 to 119 when touch operations are performed separately on touch switch 114 and touch switch 115. [Figure 4] This figure shows bar graphs representing the capacitance in the 8th to 10th rows from the top of the 20x24 area shown in Figures 3(A) and 3(B). [Figure 5] This figure shows bar graphs representing the capacitance in the 11th to 13th rows from the top of the 20x24 area shown in Figures 3(A) and 3(B). [Figure 6] This diagram illustrates the judgment process used for comparison. [Figure 7]This figure illustrates the threshold used in the determination process in the capacitive input device 100 of the embodiment. [Figure 8] This diagram illustrates the determination process performed by the determination unit 123 of the embodiment. [Figure 9] This diagram shows a flowchart representing the determination process performed by the determination unit 123. [Figure 10] This is a flowchart detailing the process in step S4. [Figure 11] This is a flowchart detailing the process in step S5. [Figure 12] This figure shows the relationship between the capacitance distribution and the first threshold (1), the second threshold (2), and the third threshold (3). [Modes for carrying out the invention]
[0009] The following describes embodiments to which the capacitive input device and capacitive input method of the present invention are applied.
[0010] <Embodiment> Figure 1 shows a steering wheel 10 on which an operating unit 110 of the capacitive input device of the embodiment is provided. The steering wheel 10 is located in the driver's seat of the vehicle, and the operating unit 110 is provided on the spokes. As an example, Figure 1 shows the operating unit 110 being operated with the thumb of the user's right hand H.
[0011] A vehicle is an automobile capable of traveling on roads using an engine and / or an electric motor as its power source. The vehicle may be equipped with various levels of autonomous driving functions as defined, for example, by the Society of Automotive Engineers International (SAE) in the United States.
[0012] As shown in an enlarged view, the operation unit 110 has, as an example, nine touch switches 111 to 119. In the enlarged view showing the touch switches 111 to 119, the cover covering the touch switches 111 to 119 is omitted. The touch switches 111 to 119 are an example of a plurality of touch switches. Here, (1) to (9) are marked in the area where the touch switches 111 to 119 are arranged.
[0013] The touch switches 111 to 119 are housed in the housing 110A and are provided on the spokes of the steering wheel 10 in a state where a cover 110B covering the operation surface on the front side of FIG. 1 is attached.
[0014] The touch switches 111 to 119 are arranged in a substantially matrix pattern with three rows in the vertical direction and three columns in the horizontal direction. The touch switches 111 to 119 are, as an example, electrodes made of a metal foil, a metal plate, a conductive film, or the like, and are connected to a control device (not shown) via wiring, a cable, or the like. The capacitance between the touch switches 111 to 119 and the hand H (see FIG. 1) changes according to the degree (distance) of proximity of the hand H to the touch switches 111 to 119.
[0015] The touch switches 111 to 119 are, as an example, used to operate various electrical equipment in a vehicle. By touching (tapping) a portion on the surface of any of the touch switches 111 to 119 on the cover 110B with a fingertip or the like, a desired electrical equipment in the vehicle can be operated. The functions of the electrical equipment that can be operated by the touch switches 111 to 119 are, for example, selecting a music track or adjusting the volume of an audio, selecting on-hook or ending of a hands-free phone, or setting a cruise control.
[0016] FIG. 2 is a diagram showing the capacitive input device 100 of the embodiment. The capacitive input device 100 includes an operation unit 110 and a control device 120. The operation unit 110 has touch switches 111 to 119 (see FIG. 1), which are omitted in FIG. 2. The capacitive input device 100 detects a touch operation on the touch switches 111 to 119 in a self-capacitance type as an example.
[0017] The operation unit 110 and the control device 120 are connected via wiring, cables, etc. The control device 120 is provided, as an example, on the steering wheel 10 and is integrally configured with the operation unit 110. Here, a form in which the control device 120 is provided on the operation unit 110 as an example and is integrally configured with the operation unit 110 will be described. However, the control device 120 may be configured separately from the operation unit 110 and provided inside the vehicle cabin outside the steering wheel 10.
[0018] The control device 120 is connected to an ECU (Electronic Control Unit) 50 that controls electrical equipment via an in-vehicle network such as CAN (Controller Area Network) or LIN (Local Interconnect Network) mounted on the vehicle. The ECU 50 is an electronic control device that controls the vehicle's audio, hands-free phone, cruise control, and other electrical equipment. Although one ECU 50 is shown in FIG. 2, a plurality of ECUs 50 may be connected to the control device 120.
[0019] The control device 120 is realized by a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an input / output interface, and an internal bus, etc.
[0020] The control device 120 has a main control unit 121, a capacitance detection unit 122, a determination unit 123, and a memory 124. The main control unit 121, the capacitance detection unit 122, and the determination unit 123 show the functions of the program executed by the control device 120 as functional blocks. Also, the memory 124 functionally represents the memory of the control device 120.
[0021] The main control unit 121 is a processing unit that overall controls the control processing of the control device 120 and executes processing other than the processing performed by the capacitance detection unit 122 and the determination unit 123.
[0022] The capacitance detection unit 122 detects the capacitance of the touch switches 111 to 119 (see Figure 1) and transmits data representing the count value of the capacitance of each of the touch switches 111 to 119 to the determination unit 123. The capacitance count value is the change from the reference value when the touch switches 111 to 119 are not being operated, and is the difference obtained by subtracting the reference value from the capacitance during operation. Hereafter, capacitance is the difference value from the reference value. The capacitance of the touch switches 111 to 119 is an example of the output of the touch switches 111 to 119. For each of the touch switches 111 to 119, one count value representing the capacitance of each touch switch 111 to 119 is obtained.
[0023] The determination unit 123 determines that a touch operation was performed on one of the touch switches 111 to 119 based on the capacitance count value of each touch switch 111 to 119 transmitted from the capacitance detection unit 122. The determination result of the determination unit 123 represents the one touch switch among the touch switches 111 to 119 that was touched. The determination result of the determination unit 123 is the detection result that the capacitive input device 100 detected which touch switch was touched. The determination process performed by the determination unit 123 will be described later.
[0024] Memory 124 stores programs and data necessary for the control device 120 to perform the judgment process. Memory 124 stores data representing the count values of the capacitance of each of the touch switches 111 to 119, as well as data generated by the judgment unit 123 during the judgment process.
[0025] Here, there may be various requirements regarding the sensitivity of the capacitive input device 100 when detecting touch operations performed on the touch switches 111 to 119. For example, if the capacitive input device 100 is installed in a vehicle designed for use in cold climates, the steering wheel 10 and the control unit 110 may be operated with gloves on the hands H. In such cases, the count value of each capacitance of the touch switches 111 to 119 tends to be small, so the threshold value in the determination process of the determination unit 123 will be lowered. This is to improve the sensitivity when detecting touch operations when gloves are worn. However, if the threshold value is lowered, there is a possibility that the count value obtained from an adjacent touch switch, in addition to the count value obtained from the touch switch where the touch operation was performed, may also exceed the threshold value, so some ingenuity is required.
[0026] As an example of this design, the determination process of the determination unit 123 in the embodiment uses three or more thresholds (three or more levels) to easily compare the capacitance of adjacent touch switches in order to identify the touch switch on which the touch operation was performed as one of the touch switches 111 to 119. Before describing the determination process of the determination unit 123 in the embodiment, the comparison determination process will be explained using Figures 3 to 6. In the comparison determination process, two (two levels) thresholds are used to identify the touch switch on which the touch operation was performed as one of the touch switches 111 to 119.
[0027] Figure 3 shows the capacitance distribution at touch switches 111 to 119 when touch operations are performed separately on touch switch 114 and touch switch 115. Figure 3(A) shows the capacitance distribution at touch switches 111 to 119 when a touch operation is performed on the central part of touch switch 114, and Figure 3(B) shows the capacitance distribution at touch switches 111 to 119 when a touch operation is performed on the central part of touch switch 115. Capacitance is shown in count values.
[0028] Figures 3(A) and 3(B) show, as an example, the analysis of a rectangular area including the entire surface of touch switches 111-119 in a plan view, divided into 480 regions arranged in 20 rows x 24 columns at 3 mm intervals. The 480 capacitance values obtained from the analysis of these 480 regions are shown. In reality, each of the touch switches 111-119 yields a single count value representing capacitance, but here, in order to analyze the capacitance distribution in detail, the 480 capacitance values obtained from the analysis of 480 regions are shown. More specifically, Figure 3(A) shows the output of touch switch 114. The output of touch switch 114 in Figure 3(A) is the output of touch switch 114 when a touch operation is performed on each of the 480 regions. Similarly, Figure 3(B) shows the output of touch switch 115. The output of touch switch 115 in Figure 3(B) is the output of touch switch 115 when a touch operation is performed on each of the 480 regions.
[0029] In Figure 3(A), when a touch operation is performed on each of the 480 areas, the output of the touch switch 114 shows that the capacitance is higher when the touch operation is performed on the central part of the touch switch 114, and decreases when the touch operation is performed on an area further away from the center of the touch switch 114. The same is true for the touch switch 115 in Figure 3(B).
[0030] Furthermore, Figures 3(A) and 3(B) show in gray the region where the capacitance exceeds the first threshold (1). The first threshold (1) is the threshold used to determine whether or not a touch operation has been performed for the nine capacitances actually obtained from the touch switches 111 to 119. The first threshold (1) is a low value that allows for the determination of whether or not a touch operation has been performed even when a glove is worn on the hand H.
[0031] As shown in Figure 3(A), when a touch operation is performed on each of the 480 areas, the area where a touch operation is determined to have occurred based on the output of the touch switch 114 and the first threshold (1) extends beyond the touch switch 114. In other words, even if a touch operation is performed on an area located near the touch switch 114 outside of it, the output of the touch switch 114 exceeds the first threshold. Similarly, as shown in Figure 3(B), when a touch operation is performed on each of the 480 areas, the area where a touch operation is determined to have occurred based on the output of the touch switch 115 and the first threshold (1) extends beyond the touch switch 115. In other words, even if a touch operation is performed on an area located near the touch switch 115 outside of it, the output of the touch switch 115 exceeds the first threshold. Thus, the area where a touch operation is determined to have occurred based on the first threshold (1) extends beyond the touch switches 114 and 115 because the first threshold (1) is a low value that allows for the determination of whether or not a touch operation has occurred even when a glove is worn on the hand H.
[0032] Therefore, when a touch operation is performed on the area of touch switch 114, there is a risk that it may be determined that a touch operation has been performed on touch switches 111, 112, 115, 117, and 118 adjacent to touch switch 114. The touch switches adjacent to touch switch 114 are touch switches 111, 112, 115, 117, and 118 located next to touch switch 114 in the horizontal, vertical, and diagonal directions. In other words, when a touch operation is performed on the area of touch switches 111, 112, 115, 117, and 118 adjacent to touch switch 114, there is a risk that it may be determined that a touch operation has been performed on touch switch 114.
[0033] Similarly, when touch switch 115 is touched, it may be incorrectly determined that touch switches 111, 112, 113, 114, 116, 117, and 118 adjacent to touch switch 115 have also been touched. The touch switches adjacent to touch switch 115 are those located next to touch switch 115 horizontally, vertically, and diagonally.
[0034] As described above, since it may be difficult to determine whether a touch operation was performed on any one of the touch switches 111 to 119 using only the first threshold (1), a second threshold (2), which has a larger value than the first threshold (1), is used in the comparison determination process.
[0035] Figure 4 is a bar graph showing the capacitance in the 8th to 10th rows from the top of the 20x24 area in Figures 3(A) and 3(B). The capacitance of touch switch 114 is shown by the white bar graph, and the capacitance of touch switch 115 is shown by the black bar graph. In Figure 4, the horizontal axis shows the capacitance from the 1st to the 24th column from the left of the 20x24 area in Figures 3(A) and 3(B). The 24th column is the rightmost column of the 20x24 area.
[0036] Furthermore, Figure 4 shows a second threshold (2) in addition to the first threshold (1). The second threshold (2) is higher than the first threshold (1), and in the comparison judgment process, it is used to determine that a touch operation has been performed on the touch switch that provides the capacitance when only one of the nine capacitances actually obtained from the touch switches 111 to 119 exceeds the second threshold (2).
[0037] Thus, in the comparison judgment process, in addition to the first threshold (1), a second threshold (2) with a value greater than the first threshold (1) is used to identify the touch switch on which the touch operation was performed. However, a problem may arise if a capacitance exceeding the second threshold (2) cannot be obtained. The method and problems of identifying the single touch switch on which the touch operation was performed when no capacitance exceeding the second threshold (2) exists in the comparison judgment process will be described later with reference to Figure 6.
[0038] In row 8, no capacitance exceeding the second threshold (2) is obtained, and in columns 10 through 12, enclosed by the dashed rectangle, both touch switches 114 and 115 exceed the first threshold (1).
[0039] In row 9, capacitance exceeding the second threshold (2) is obtained, but in columns 10 and 11, enclosed by dashed rectangles, both touch switches 114 and 115 exceed the first threshold (1), but neither exceeds the second threshold (2).
[0040] In the 10th row, capacitance exceeding the second threshold (2) is obtained, but in the 10th and 11th columns enclosed by the dashed rectangle, both touch switches 114 and 115 exceed the first threshold (1), but neither exceeds the second threshold (2).
[0041] Figure 5 is a bar graph showing the capacitance in the 11th to 13th rows from the top of the 20x24 area in Figures 3(A) and 3(B). The method of representing capacitance in Figure 5 is the same as the method of representing capacitance in Figure 4.
[0042] In row 11, capacitance exceeding the second threshold (2) is obtained, but in columns 10 and 12, enclosed by dashed rectangles, both touch switches 114 and 115 exceed the first threshold (1), but neither exceeds the second threshold (2).
[0043] In the 12th row, capacitance exceeding the second threshold (2) is obtained, and in the 9th and 12th columns enclosed by the dashed rectangle, both touch switches 114 and 115 exceed the first threshold (1), but neither exceeds the second threshold (2).
[0044] In row 13, no capacitance exceeding the second threshold (2) is obtained, and in columns 10 and 11 enclosed by dashed rectangles, both touch switches 114 and 115 exceed the first threshold (1), but neither exceeds the second threshold (2).
[0045] As shown in Figures 4 and 5, even when using a first threshold (1) and a second threshold (2) that is greater than the first threshold (1), it may not be possible to obtain a capacitance exceeding the second threshold (2) in both touch switches 114 and 115. This creates a gray area near the boundary between touch switches 114 and 115 where it is impossible to determine which switch is being used for the touch operation.
[0046] Figure 6 illustrates the determination process used for comparison. Figures 6(A) to 6(C) show simplified touch switches 114 and 115, and the capacitances obtained by touch switches 114 and 115.
[0047] Figure 6(A) shows the capacitance when the fingertip FT is touching the area of the touch switch 114 that is closer to the touch switch 115. This position of the fingertip FT can occur during the process of the fingertip FT moving from the touch switch 114 to the touch switch 115. The capacitance of the touch switch 114 is above the first threshold (1) but below the second threshold (2), and the capacitance of the touch switch 115 is lower than the capacitance of the touch switch 114, but is above the first threshold (1) and below the second threshold (2). In such a case, it is determined that the touch operation was performed on the touch switch 114, whose capacitance exceeded the first threshold (1) first in the time series.
[0048] Figure 6(B) shows the capacitance when the fingertip FT is touching both touch switches 114 and 115. This situation can occur when the fingertip FT moves from touch switch 114 to touch switch 115, or when the fingertip FT moves from the direction of touch switch 111 or 112, or from the direction of touch switch 117 or 118 towards touch switches 114 and 115. The capacitance of both touch switches 114 and 115 exceeds the first threshold (1). In such cases, it is not possible to determine whether the touch operation is being performed on touch switch 114 or 115.
[0049] Figure 6(C) shows the capacitance when the fingertip FT is touching the touch switch 115 but not the touch switch 114. The capacitance of the touch switch 114 is above the first threshold (1) but below the second threshold (2), and the capacitance of the touch switch 115 is above the second threshold (2). In such cases, it is determined that a touch operation has been performed on the touch switch 115. However, the capacitance may differ when wearing gloves, and it may also differ depending on the individual.
[0050] As described above, the comparison judgment process using two thresholds, a first threshold (1) and a second threshold (2), has a problem in that it cannot determine which of the two touch switches the touch operation is being performed on when the fingertip FT is located at the boundary between the two touch switches, as shown in Figure 6(B). This problem is particularly noticeable in the area enclosed by the dashed rectangle near the boundary between touch switches 114 and 115 in Figures 4 and 5, and can occur at the boundary between adjacent touch switches for all of touch switches 111 to 119.
[0051] Therefore, the determination process of the determination unit 123 in the embodiment solves these problems. The determination process of the determination unit 123 in the embodiment will be described below with reference to Figures 7 to 12. In the determination process of the determination unit 123 in the embodiment, the touch switch on which the touch operation is being performed is identified by using at least three thresholds (first threshold (1), second threshold (2), and third threshold (3)). The second threshold (2) and third threshold (3) of the at least three thresholds are examples of multiple comparison thresholds, and are examples of multiple comparison thresholds that are significantly different from each other and greater than the first threshold. The third threshold (3) is an example of the largest comparison threshold among the multiple comparison thresholds. Note that the second threshold (2) is different from the second threshold (2) used for comparison described above. Details will be described later.
[0052] Figure 7 illustrates the threshold values used in the determination process in the capacitive input device 100 of the embodiment. In Figures 7(A) and 7(B), the regions where the capacitance exceeds the first threshold (1) when a touch operation is performed on the touch switches 114 and 115 are shown in gray. In other words, the gray regions represent the regions corresponding to the first threshold (1).
[0053] The first threshold (1) in the embodiment is a low value that allows for the determination of whether or not a touch operation has been performed, even when a touch operation is performed with the fingertip FT of a gloved hand H, similar to the first threshold (1) in the comparative determination process. Such a first threshold (1) is a value based on the capacitance count value (an example of a sensor value) detected at the touch switch when a hand H (see Figure 1), which is an example of an operating body, operates the outer edge or vicinity of the outer edge of the touch switch.
[0054] The outer edge of a touch switch is the edge surrounding each touch switch, and the vicinity of the outer edge of a touch switch is the region inside and outside the outer edge of each touch switch where a capacitance equivalent to that at the outer edge (for example, a difference of ±10% or less) can be obtained. In this way, in order to determine the first threshold (1) that makes it possible to determine whether or not a touch operation has been performed even when a glove is worn on the hand H, the region corresponding to the first threshold (1) extends beyond the outer edge of each touch switch.
[0055] When a gloved hand H touches each touch switch with its fingertip FT, the capacitance detected at each touch switch is smaller than the capacitance detected at each touch switch when the glove is used. This is because the distance between the touch switch and the fingertip FT is longer due to the thickness of the glove. Therefore, the first threshold (1) is smaller than the threshold at which a touch operation can be determined when using a bare hand, and the region corresponding to the first threshold (1) is wider than the region corresponding to the threshold at which a touch operation can be determined when using a bare hand.
[0056] In the determination process of the determination unit 123 of the embodiment, the second threshold (2) has a value greater than the first threshold (1), similar to the second threshold (2) for comparison. However, for touch switches 114 and 115, it differs from the second threshold (2) for comparison in that it corresponds to the area indicated by the dashed line inside the gray area. That is, in the determination process of the determination unit 123 of the embodiment, the value of the second threshold (2) is set so that a capacitance exceeding the second threshold (2) is obtained within the area indicated by the dashed line. The dashed area corresponding to the second threshold (2) is the central area excluding the part close to the outer edge of the gray area corresponding to the first threshold (1). In other words, the second threshold (2) is greater than the first threshold (1).
[0057] Furthermore, in the determination process of the determination unit 123 of the embodiment, the third threshold (3) corresponds to the area indicated by the dashed line inside the gray area for the touch switches 114 and 115. That is, in the determination process of the determination unit 123 of the embodiment, the value of the third threshold (3) is set so that capacitance exceeding the third threshold (3) is obtained within the area indicated by the dashed line.
[0058] The area indicated by the dashed line corresponding to the third threshold (3) is included in the area indicated by the dashed line corresponding to the second threshold (2), and is the central area within the area indicated by the dashed line. In order to use the third threshold (3) to determine that the touch operation is performed more centrally than the determination based on the second threshold (2), the area indicated by the dashed line corresponding to the third threshold (3) is located on the central side of the area indicated by the dashed line corresponding to the second threshold (2). In other words, the third threshold (3) is larger than the second threshold (2).
[0059] The third threshold (3) is a value based on the sensor value detected by the touch switch when the hand H or fingertip FT operates the central area of the touch switch. The dashed-dotted area corresponding to the third threshold (3) is an example of the central area of touch switches 114 and 115.
[0060] When using the three thresholds described above—the first threshold (1), the second threshold (2), and the third threshold (3)—the second threshold (2) may be set as a value between the first threshold (1) and the third threshold (3). For example, the second threshold (2) may be set as an intermediate value between the first threshold (1) and the third threshold (3), or as a value obtained by multiplying the third threshold (3) by a predetermined percentage.
[0061] The first threshold (1) and the third threshold (3) can be set based on the detection sensitivity of the touch switch, the area of the touch switch, or the distance between the touch switch and adjacent touch switches. Detection sensitivity is expressed as the capacitance of the touch switch for a given touch operation; a larger capacitance for a given touch operation results in higher detection sensitivity, while a smaller capacitance results in lower detection sensitivity.
[0062] Furthermore, Figures 7(A) and 7(B) show the regions corresponding to the three first thresholds (1), second thresholds (2), and third thresholds (3) for touch switches 114 and 115, and the same applies to touch switches 111-113 and 116-119.
[0063] In the determination process of the determination unit 123 of this embodiment, the touch switch on which a touch operation is performed is identified by using at least three thresholds for each of the touch switches 111 to 119. Below, as an example, the determination process for identifying the touch switch on which a touch operation is performed will be described using three first thresholds (1), second thresholds (2), and third thresholds (3).
[0064] Figure 8 is a diagram illustrating the determination process performed by the determination unit 123 of the embodiment. Figures 8(A) to 8(C) show simplified touch switches 114 to 116 and the capacitance obtained by the touch switches 114 to 116.
[0065] Figure 8(A) shows the capacitance when the fingertip FT is touching touch switch 114 but close to touch switch 115. This position of the fingertip FT can occur during the process of the fingertip FT moving from touch switch 114 to touch switch 115. The capacitance of touch switch 114 exceeds the third threshold (3), the capacitance of touch switch 115 exceeds the first threshold (1) but is less than the second threshold (2), and the capacitance of touch switch 116 is less than the first threshold (1). In this case, where there is only one touch switch with a capacitance exceeding the third threshold (3), it is determined that a touch operation was performed on touch switch 114, whose capacitance exceeds the third threshold (3). Touch switch 114, whose capacitance exceeds the third threshold (3), is an example of a touch switch corresponding to a capacitance (output) that exceeds the third threshold (3), and the fact that there is only one touch switch with a capacitance exceeding the third threshold (3) is an example of there being only one output that exceeds the third threshold (3). Furthermore, in this case, the capacitance of the touch switch 114 is an example of one output, and determining that a touch operation has been performed on the touch switch 114 is an example of extracting one output.
[0066] Furthermore, the third threshold (3) should be set to a value that does not exceed the capacitance of the multiple touch switches when the fingertip FT spans multiple touch switches and is touching multiple touch switches.
[0067] Figure 8(B) shows the capacitance when the fingertip FT is touching both touch switches 114 and 115. This situation can occur when the fingertip FT moves from touch switch 114 to touch switch 115. The capacitances of both touch switches 114 and 115 are below the third threshold (3) and above the second threshold (2). In such cases, it is determined that the touch operation was performed on touch switch 114, which was judged to have exceeded the first threshold (1) first in the time series. Note that the state in which the capacitances of both touch switches 114 and 115 are below the third threshold (3) and above the second threshold (2) is an example of a state in which there are two outputs below one of the comparison thresholds, and the capacitances of touch switches 114 and 115 are an example of two outputs.
[0068] Furthermore, even if the capacitances of both touch switches 114 and 115 are below the second threshold (2) but exceed the first threshold (1), it is sufficient to determine that the touch operation was performed on the touch switch whose capacitance exceeded the first threshold (1) first in the time series.
[0069] Figure 8(C) shows the capacitance when the fingertip FT is touching touch switch 115 but is about to touch touch switch 114. This position of the fingertip FT can occur during the process of the fingertip FT moving from touch switch 114 to touch switch 115. The capacitance of touch switch 115 exceeds the third threshold (3), the capacitance of touch switch 114 exceeds the second threshold (2) but is less than or equal to the third threshold (3), and the capacitance of touch switch 116 is less than or equal to the first threshold (1). In this case, where there is only one touch switch with a capacitance exceeding the third threshold (3), it is determined that a touch operation was performed on touch switch 115, whose capacitance exceeds the third threshold (3).
[0070] The determination process described using Figures 8(A) to 8(C) is a part of the determination process of the determination unit 123. The determination unit 123 performs the following determination process.
[0071] The determination unit 123 determines that a touch operation has been performed on the touch switch whose capacitance exceeds the third threshold (3) if there is only one touch switch whose capacitance exceeds the third threshold (3).
[0072] The determination unit 123 determines that a touch operation has been performed on the touch switch whose capacitance exceeds the second threshold (2) if there is only one touch switch whose capacitance exceeds the second threshold (2).
[0073] The determination unit 123 determines that a touch operation has been performed on the touch switch whose capacitance exceeds the first threshold (1) if there is only one touch switch whose capacitance exceeds the first threshold (1).
[0074] Furthermore, in cases other than those described above, if there are multiple touch switches whose capacitance exceeds the first threshold (1), the determination unit 123 makes the following determination.
[0075] The determination unit 123 determines that if the capacitance of all touch switches is less than the third threshold (3) and there are multiple touch switches with capacitances exceeding the second threshold (2), the touch operation was performed on the touch switch whose capacitance exceeded the second threshold (2) first in time.
[0076] Furthermore, if the capacitance of all touch switches is less than the second threshold (2), and there are multiple touch switches with capacitances exceeding the first threshold (1), it is determined that the touch operation was performed on the touch switch whose capacitance exceeded the first threshold (1) first (earliest) in time series.
[0077] Furthermore, if there are multiple touch switches with capacitances exceeding the third threshold (3), the determination unit 123 determines that the touch operation was performed on the touch switch whose capacitance exceeded the third threshold (3) first in time. The third threshold (3) is set to a value that does not exceed the capacitance of multiple touch switches when the fingertip FT is touching multiple touch switches. However, for example, if multiple fingers or palms touch multiple touch switches, it is possible that there are multiple touch switches with capacitances exceeding the third threshold (3). For this reason, if there are multiple touch switches with capacitances exceeding the third threshold (3), the determination unit 123 should be configured to determine that the touch operation was performed on the touch switch whose capacitance exceeded the third threshold (3) first in time.
[0078] Furthermore, if no touch switch has a capacitance exceeding the first threshold (1), the determination unit 123 determines that no touch operation has been performed on any of the touch switches. While this description explains a configuration in which the touch operation is determined to have occurred on the touch switch whose capacitance exceeded any threshold first (earliest) in time, it is also possible to determine that the touch operation was performed on the touch switch whose capacitance exceeded any threshold last (latest).
[0079] Figure 9 is a flowchart showing the determination process executed by the determination unit 123. The flowchart shown in Figure 9 represents the process by the capacitive input method of the embodiment. While the power supply of the capacitive input device 100 is turned on, the determination unit 123 repeatedly executes the series of processes from the start to the end of the flowchart shown in Figure 9 at a predetermined control cycle. The power supply of the capacitive input device 100 is turned on, for example, when the ignition switch of the vehicle on which the capacitive input device 100 is installed is in accessory mode or on.
[0080] The determination unit 123 acquires the capacitance of all touch switches 111 to 119 and determines whether there are any touch switches whose capacitance exceeds the first threshold (1) (step S1). The determination unit 123 performs the process of step S1 by comparing the capacitance of all touch switches 111 to 119 with the first threshold (1). The process of step S1 is an example of the first comparison, and the result of the process of step S1 is an example of the comparison result in the first comparison.
[0081] In step S1, the determination unit 123 obtains the capacitance of all touch switches 111 to 119 from the capacitance detection unit 122. The capacitance detection unit 122 detects the capacitance of touch switches 111 to 119 by selecting them one by one in chronological order.
[0082] If the determination unit 123 determines that there is a touch switch whose capacitance exceeds the first threshold (1) (S1: YES), it stores the touch information, which is the previous final determination result in the determination process of the determination unit 123 for all touch switches 111 to 119 (flowchart in Figure 9), in a predetermined area of the memory 124 (step S2). The touch information indicates which touch switch was determined to have been touched at the end of the flowchart in Figure 9. In the first flow, there is no final determination result from the previous flow, so there is no touch information. If it is determined that no touch operation has been performed on any of the touch switches 111 to 119, the touch information will indicate that no touch operation has been performed on any of the touch switches 111 to 119.
[0083] The determination unit 123 stores the capacitance of all touch switches 111 to 119 in the memory 124 (step S3).
[0084] The determination unit 123 determines for all touch switches 111 to 119 whether they are in the state of ON 1, ON 2, ON 3, or OFF (below the first threshold (1)). The process of determining whether the capacitance exceeds the second threshold (2) (ON 2) and the process of determining whether the capacitance exceeds the third threshold (3) (ON 3) are examples of the second comparison, and the results of these processes are examples of the comparison results in the second comparison. The determination unit 123 determines that the state of a touch switch whose capacitance exceeds both the first threshold (1) and the second threshold (2) is ON 2. The determination unit 123 determines that the state of a touch switch whose capacitance exceeds both the second threshold (2) and the third threshold (3) is ON 3. As a result, touch switches whose capacitance exceeds the first threshold (1) are determined to be either ON 1, ON 2, or ON 3.
[0085] The determination unit 123 compares the information of ON1, ON2, and ON3 with the adjacent touch switches for the switches determined to be ON1, ON2, or ON3 in step S4, and identifies all touch switches for which a touch operation can be determined to have occurred (step S5).
[0086] The determination unit 123 determines whether, among the touch switches identified in step S5 as being able to determine that a touch operation has been performed, there is a touch switch that was determined to have been touched based on the touch information stored in step S2 as the previous final determination result (step S6).
[0087] If the determination unit 123 determines that there is a touch switch that has been determined to have been touched (S6: YES), it outputs the touch information stored in step S2 as the previous final determination result (step S7). After completing the process in step S7, the determination unit 123 terminates the series of processes (end).
[0088] Furthermore, if the determination unit 123 determines in step S6 that there are no touch switches that were determined to have been touched in step S2 (S6: NO), it outputs touch information indicating that a touch operation was performed on the touch switch with the smallest region number (1) to (9) among the touch switches identified in step S5 (step S8). For example, as shown in Figure 1, when operating touch switches 111 to 119 with the thumb of the right hand H gripping the spokes of the steering wheel 10, the furthest from the thumb is touch switch 111, the closest is touch switch 119, and so on, in the order of touch switches 111 to 119. For this reason, if operations occur simultaneously, priority is given to determining that the touch operation was performed on the furthest touch switch. Note that this order of determination is just an example, and for example, as explained in Figure 8, it may also be determined that a touch operation was performed on the touch switch whose capacitance exceeded the first threshold (1), second threshold (2), or third threshold (3) first (earliest) in the time series.
[0089] Furthermore, if the determination unit 123 determines in step S1 that there are no touch switches whose capacitance exceeds the first threshold (1) (S1: NO), it outputs touch information indicating that no touch switches have been touched (step S9).
[0090] Figure 10 is a flowchart detailing the process in step S4. The process shown in Figure 10 includes steps S400 to S409.
[0091] The determination unit 123 sets the determination result of all touch switches 111 to 119 to OFF (step S400).
[0092] The determination unit 123 selects one specific touch switch from all touch switches 111 to 119 (step S401). Here, it is sufficient to select any one of the touch switches 111 to 119 as the specific touch switch, and the process of steps S401 to S409 is repeated 9 times to select all of the touch switches 111 to 119 as the specific touch switch once each. For example, one could select touch switches 111 to 119 in order. The output of the specific touch switch is an example of a specific output. The output of touch switches other than the specific touch switch is an example of a non-specific output.
[0093] The determination unit 123 determines whether the capacitance of a specific touch switch exceeds a first threshold (1) (step S402).
[0094] If the determination unit 123 determines that the capacitance of a specific touch switch exceeds the first threshold (1) (S402: YES), it then determines whether the capacitance of the specific touch switch exceeds the second threshold (2) (step S403).
[0095] If the determination unit 123 determines that the capacitance of a specific touch switch exceeds the second threshold (2) (S403: YES), it then determines whether the capacitance of the specific touch switch exceeds the third threshold (3) (step S404). By performing the processing in steps S402 to S404, the determination unit 123 determines whether the capacitance of a specific touch switch exceeds any of the comparison thresholds.
[0096] If the determination unit 123 determines that the capacitance of a specific touch switch exceeds the third threshold (3) (S404: YES), it sets the determination result of the specific touch switch to ON 3 (step S405).
[0097] The determination unit 123 determines whether all touch switches 111 to 119 have been selected as specific touch switches (step S406).
[0098] If the determination unit 123 determines that none of the touch switches 111-119 have been selected as specific touch switches (S406: NO), it returns the flow to step S401. This is because it selects a new specific touch switch and repeatedly executes the processes from step S401 to step S409.
[0099] Furthermore, if the determination unit 123 determines in step S402 that the capacitance of a specific touch switch does not exceed the first threshold (1) (S402: NO), it sets the determination result of the specific touch switch to OFF (step S407).
[0100] Furthermore, if the determination unit 123 determines that the capacitance of a specific touch switch does not exceed the second threshold (2) (S403: NO), it sets the determination result of the specific touch switch to ON 1 (step S408).
[0101] Furthermore, if the determination unit 123 determines that the capacitance of a particular touch switch does not exceed the third threshold (3) (S404: NO), it sets the determination result of the particular touch switch to ON 2 (step S409).
[0102] Figure 11 is a flowchart detailing the process in step S5. The process shown in Figure 11 includes steps S500 to S509.
[0103] The determination unit 123 initializes the output array to OFF for the switches determined to be ON 1, ON 2, and ON 3 in step S4 (step S500). The output array is stored in a predetermined area of the memory 124 that holds the determination result in step S5, separate from the area that stores the ON 1, ON 2, ON 3, and OFF determination results in step S4.
[0104] The determination unit 123 selects one of the touch switches that was not determined to be off in step S4 as a specific touch switch (step S501).
[0105] The determination unit 123 determines whether a specific touch switch is set to ON 1 (step S502).
[0106] If the determination unit 123 determines that a specific touch switch is set to ON 1 (S502: YES), it determines whether the touch switch adjacent to the specific touch switch is set to ON 2 or ON 3 (step S503).
[0107] If the determination unit 123 determines that a touch switch adjacent to a specific touch switch is set to ON 2 or ON 3 (S503: YES), it adds the state of the specific touch switch to OFF and adds it to the output array (step S504).
[0108] The determination unit 123 determines whether all touch switches that were not set to "off" in step S4 have been selected (step S505). If the determination unit 123 determines that all have been selected (S505: YES), it proceeds to step S6.
[0109] Furthermore, if the determination unit 123 determines in step S502 that a specific touch switch is not set to ON 1 (S502: NO), it determines whether the specific touch switch is set to ON 2 (step S506).
[0110] If the determination unit 123 determines that a specific touch switch is set to ON 2 (S506: YES), it then determines whether a touch switch adjacent to that specific touch switch is set to ON 3 (step S507).
[0111] If the determination unit 123 determines that a touch switch adjacent to a specific touch switch is set to ON 3 (S507: YES), it adds the state of the specific touch switch to OFF and adds it to the output array (step S508).
[0112] Furthermore, if the determination unit 123 determines in step S506 that a specific touch switch is not set to ON 2 (S506: NO), or if it determines in step S507 that a touch switch adjacent to a specific touch switch is not set to ON 3 (S507: NO), it sets the state of the specific touch switch to ON and adds it to the output array (step S509).
[0113] Based on the above, the touch switch among touch switches 111 to 119 that is currently being touched can be determined.
[0114] Figure 12 shows the relationship between the capacitance distribution and the first threshold (1), second threshold (2), and third threshold (3). Figure 12 shows a white bar graph showing the capacitance when touch operation is performed on the touch switch 114 shown in Figure 3(A), a black bar graph showing the capacitance when touch operation is performed on the touch switch 115 shown in Figure 3(B), and the first threshold (1), second threshold (2), and third threshold (3). The white and black bar graphs shown in Figure 12 are the same as the white and black bar graphs shown in Figure 4(B).
[0115] As shown in Figure 12, capacitance exceeding the third threshold (3) is obtained in columns 5 through 9, which correspond to the lateral central portion of touch switch 114, and capacitance exceeding the third threshold (3) is obtained in columns 12 through 15, which correspond to the lateral central portion of touch switch 115. Furthermore, in rows 10 and 11, which correspond to the boundary between touch switch 114 and touch switch 115, in row 10 the capacitance of touch switch 114 exceeds the second threshold (2), but the capacitance of touch switch 115 is below the second threshold (2), and in row 11 the capacitance of touch switch 114 is below the second threshold (2), but the capacitance of touch switch 115 exceeds the second threshold (2).
[0116] Therefore, a capacitive input device 100 can be provided that can determine which of multiple touch switches has been touched. The capacitive input device 100 has multiple threshold levels so that the superiority or inferiority of detection sensitivity (electrostatic sensitivity) can be compared in fine areas, and as a result, it can smoothly determine when a finger sliding motion has occurred.
[0117] In the above, an example of multiple comparison thresholds is described as a second threshold (2) and a third threshold (3), and the determination unit 123 uses three thresholds, the first threshold (1), the second threshold (2), and the third threshold (3), to determine which of the touch switches 111 to 119 the touch switch that was touched was. However, the number of multiple comparison thresholds may be three or more. That is, the determination unit 123 may use four or more thresholds to determine which of the touch switches 111 to 119 the touch switch that was touched was.
[0118] Furthermore, although the above description has focused on a configuration in which the operating unit 110 has nine touch switches 111 to 119, the operating unit 110 only needs to have multiple touch switches, and the number of touch switches can be any number as long as it is two or more.
[0119] Furthermore, while the above describes a configuration in which the first threshold (1) is a low value that allows for the determination of whether or not a touch operation has been performed even when a glove is worn on the hand H, the first threshold (1) is not limited to a low value that allows for the determination of whether or not a touch operation has been performed even when the capacitance of the touch switch is smaller than that of a touch operation performed with a bare hand.
[0120] Although exemplary embodiments of the capacitive input device and capacitive input method of the present invention 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]
[0121] 10 Steering Wheel 100 Capacitive Input Devices 110 Operation section 111-119 Touch switches 120 Control device 121 Main Control Unit 122 Capacitance detection unit 123 Judgment section 124 memory
Claims
1. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. Includes, The determination unit, A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. If, as a result of the second comparison, there is one output that exceeds any of the multiple comparison thresholds, it is determined that the touch operation was performed on the touch switch corresponding to that one output among the multiple touch switches. In the second comparison described above, if there are multiple outputs among the multiple touch switches that are greater than the first threshold, Selecting one of the aforementioned multiple outputs as a specific output, Determine whether the selected specific output exceeds one of the comparison thresholds, and whether any other non-specific output among the multiple outputs does not exceed one of the comparison thresholds. By performing the above for the multiple outputs, A capacitive input device that extracts one of the aforementioned outputs that exceeds any of the aforementioned comparison thresholds.
2. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. Includes, The determination unit, A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. Capacitive input device, which determines that the touch operation was performed on the touch switch corresponding to the output obtained first or the output obtained later among the multiple touch switches, if, as a result of the second comparison, there are two outputs that are below one of the multiple comparison thresholds, and the two outputs are within the range between two adjacent comparison thresholds among the multiple comparison thresholds, or within the range between the lowest comparison threshold among the multiple comparison thresholds and the first threshold.
3. In the second comparison, if there are multiple outputs among the multiple touch switches that are greater than the first threshold, the determination unit will Selecting one of the aforementioned multiple outputs as a specific output, Determine whether the selected specific output is below any of the comparison thresholds, and whether any of the non-specific outputs among the multiple outputs other than the selected specific output are below any of the comparison thresholds. By performing the above for the multiple outputs, The capacitive input device according to claim 2, which extracts the two outputs that are less than or equal to either of the aforementioned comparison thresholds.
4. The capacitive input device according to claim 1, wherein the non-specific output is the output of a touch switch adjacent to the touch switch from which the specific output was obtained, among the outputs other than the selected specific output from the plurality of outputs.
5. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. Includes, The determination unit, A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. If, as a result of the second comparison, there is one output that exceeds any of the multiple comparison thresholds, it is determined that the touch operation was performed on the touch switch corresponding to that one output among the multiple touch switches. A capacitive input device in which the largest of the plurality of comparison thresholds and the first threshold are set based on the detection sensitivity of the touch switch, the area of the touch switch, or the distance between the touch switch and an adjacent touch switch.
6. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. Includes, The determination unit, A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. If, as a result of the second comparison, one of the multiple comparison thresholds exceeds the same comparison threshold, the determination unit determines that the touch operation was performed on the touch switch corresponding to that one output among the multiple touch switches. A capacitive input device in which the largest of the aforementioned multiple comparison thresholds is a value based on the sensor value detected by the touch switch when the operating body operates the central area of the touch switch.
7. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. Includes, The determination unit, A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. The first threshold is a value based on the sensor value detected by the touch switch when the operating body operates the outer edge or vicinity of the outer edge of the touch switch, in a capacitive input device.
8. The capacitive input device according to any one of claims 1 to 7, wherein the plurality of touch switches are switches provided on the steering wheel of a vehicle.
9. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. In a capacitive input device, including, The determination unit A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. If, as a result of the second comparison, there is one output that exceeds any of the multiple comparison thresholds, it is determined that the touch operation was performed on the touch switch corresponding to that one output among the multiple touch switches. In the second comparison described above, if there are multiple outputs among the multiple touch switches that are greater than the first threshold, Selecting one of the aforementioned multiple outputs as a specific output, Determine whether the selected specific output exceeds one of the comparison thresholds, and whether any other non-specific output among the multiple outputs does not exceed one of the comparison thresholds. By performing the above for the multiple outputs, A capacitive input method for extracting one of the aforementioned comparison thresholds that exceeds any of the aforementioned comparison thresholds.
10. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. In a capacitive input device, including, The determination unit A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. Capacitive input method, wherein, as a result of the second comparison, if there are two outputs that are below one of the multiple comparison thresholds, and the two outputs are within the range between two adjacent comparison thresholds, or within the range between the lowest comparison threshold and the first threshold, it is determined that the touch operation was performed on the touch switch corresponding to the output obtained first among the two outputs, or the output obtained later among the two outputs, among the multiple touch switches.
11. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. In a capacitive input device, including, The determination unit A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. If, as a result of the second comparison, there is one output that exceeds any of the multiple comparison thresholds, it is determined that the touch operation was performed on the touch switch corresponding to that one output among the multiple touch switches. A capacitive input method in which the largest of the plurality of comparison thresholds and the first threshold are set based on the detection sensitivity of the touch switch, the area of the touch switch, or the distance between the touch switch and an adjacent touch switch.
12. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. In a capacitive input device, including, The determination unit A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. If, as a result of the second comparison, one of the multiple comparison thresholds exceeds the same comparison threshold, the determination unit determines that the touch operation was performed on the touch switch corresponding to that one output among the multiple touch switches. A capacitive input method in which the largest of the aforementioned multiple comparison thresholds is a value based on the sensor value detected by the touch switch when the operating body operates the central area of the touch switch.
13. Multiple touch switches, A determination unit that determines whether or not a touch operation was performed on any one of the multiple touch switches based on the output of the multiple touch switches. In a capacitive input device, including, The determination unit A first comparison is performed by comparing a first threshold used to determine whether or not a touch operation has been performed with each of the outputs of the plurality of touch switches. A second comparison is performed in which the output of the plurality of touch switches that is greater than the first threshold is compared with a plurality of comparison thresholds that are greater than the first threshold and are different from each other. Based on the comparison results obtained in the first comparison or the second comparison, it is determined whether or not a touch operation was performed on any one of the plurality of touch switches. Capacitive input method, wherein the first threshold is a value based on a sensor value detected by the touch switch when the operating body operates the outer edge or vicinity of the outer edge of the touch switch.