Touch detection device, touch panel unit, and touch detection method

Abstract

To provide a touch detection device, a touch panel unit and a touch detection method which provide a novel method which contributes to suppressing false detection with a higher accuracy when touch on a capacitive touch panel is detected.SOLUTION: A touch detection device 6 comprises a touch detection unit 11 which, when a detection value of one point becomes equal to or more than a touch detection threshold value, determines whether or not it is in a first state in which the detection value of the one point is alternately changed to a plus side and a minus side with respect to a reference value as time elapses, or determines whether or not it is in a second state in which the detection value of the point in the periphery of the one point is alternately changed to the plus side and the minus side with respect to the reference value toward the outside from the one point, and does not detect the touch in the first state or the second state.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a touch detection device, a touch panel, and a touch detection method, and is particularly suitable for use in a touch detection device that detects a touch on a capacitive touch panel, a touch panel unit including the touch panel and the touch detection device, and a touch detection method using the touch detection device.

Background Art

[0002] Currently, capacitive touch panels are widely used. A capacitive touch panel detects a touch based on a change in the capacitance of points scattered on the touch surface. Therefore, when electrostatic noise that changes the capacitance of each point occurs, there is a characteristic that false detection may occur due to the electrostatic noise. Conventionally, for capacitive touch panels, techniques for suppressing false detection caused by electrostatic noise have been proposed.

[0003] For example, as existing techniques for suppressing false detection due to electrostatic noise, there are the following techniques. That is, when a detection value based on the capacitance at a certain point becomes equal to or greater than a touch detection threshold value, instead of detecting a touch at this time, it is determined whether the detection value is not equal to or greater than another threshold value (a threshold value that exceeds the touch detection value and is likely not to be exceeded by a detection value related to a normal touch but may be exceeded in the case of electrostatic noise). If the detection value is equal to or greater than the other threshold value, there is a technique of not detecting a touch. Also, when a detection value at a certain point becomes equal to or greater than a touch detection threshold value, it is determined whether the distribution of points with a detection value equal to or greater than a certain value is in a specific pattern (a pattern that is likely not to be a normal touch but may be in the case of electrostatic noise). If it is in the specific pattern, there is a technique of not detecting a touch.

[0004] Furthermore, for example, Patent Document 1 discloses the following technology for suppressing false detections caused by electrostatic noise. Specifically, the touch panel controller 17 of Patent Document 1 is configured to detect a detected value (capacitance value) corresponding to the change in capacitance at each point of the capacitive touch panel 6. When the detected value at a certain point becomes equal to or greater than the capacitance threshold C1, the touch panel controller 17 does not detect a touch at this point, but starts measuring the elapsed time since the detected value became equal to or greater than the capacitance threshold C1. If the detected value becomes equal to the capacitance threshold C2 (> capacitance threshold C1) within a predetermined time, it is considered a false touch, and a touch is detected only if the detected value becomes equal to the capacitance threshold C2 (> capacitance threshold C1) after the predetermined time. According to this technology of Patent Document 1, it is possible to suppress false detections caused by electrostatic noise, taking into account that there is a difference in the change in the detected value after it becomes equal to the capacitance threshold C1 depending on whether the cause of the detected value becoming equal to the capacitance threshold C1 is a normal touch or due to electrostatic noise.

[0005] Patent Document 2 describes a technique that suppresses false detections by detecting changes in acceleration applied to the touch panel in addition to detecting changes in capacitance, and by detecting touches while taking the changes in acceleration into account. Patent Document 3 describes a technique that prevents malfunctions due to noise when a touch panel and a liquid crystal display device are used in close proximity, by forming noise detection wiring (NDL) on the liquid crystal display panel 11 for noise detection, and detecting the touch position by reflecting the detection results of the noise detection wiring (NDL). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2018-077755 [Patent Document 2] Japanese Patent Publication No. 2013-109636 [Patent Document 3] Japanese Patent Publication No. 2011-180401 [Overview of the project] [Problems that the invention aims to solve]

[0007] As mentioned above, while technologies to suppress false detections due to electrostatic noise have been proposed for capacitive touch panel touch detection, there is always a demand in this field for suppressing false detections due to electrostatic noise with higher accuracy. To meet this demand, there is a need for novel methods that can contribute to improving accuracy.

[0008] This invention was made to solve these problems and aims to provide a new method that can contribute to suppressing false detections with higher accuracy in touch detection of capacitive touch panels. [Means for solving the problem]

[0009] To solve the above-mentioned problems, the present invention performs a process to determine whether the detected value detected at a point on the touch surface of a touch panel is in a first state, where the detected value changes alternately to the positive and negative side relative to a reference value over time, or whether the distribution of detected values ​​detected at points surrounding that point is in a second state, where the distribution changes alternately to the positive and negative side relative to a reference value as the point moves outward from the point. If it is determined that the state is either the first or second state, the present invention does not detect a touch. [Effects of the Invention]

[0010] The simplest method for detecting a touch is to detect a touch when the detected value (a value corresponding to capacitance) at a single point exceeds a predetermined touch detection threshold. The inventors have found that when the detected value at a single point exceeds the touch detection threshold due to electrostatic noise, the following phenomena occur: the detected value at that single point alternates between positive and negative relative to the reference value over time, and the distribution of detected values ​​at points surrounding that single point alternates between positive and negative relative to the reference value as it moves outward from that single point.

[0011] Based on the above, according to the present invention configured as described above, when the detected value of a point exceeds the touch detection threshold, it is determined whether the detected value of that point is in a first state in which it alternates between positive and negative relative to a reference value over time, or whether the distribution of detected values ​​of points around that point is in a second state in which it alternates between positive and negative relative to a reference value as it moves outward from that point. If it is in the first or second state, no touch is detected. Therefore, false detections can be suppressed in an accurate manner that reflects the characteristics of the influence of electrostatic noise on the detected value of each point. In other words, the present invention provides a new method that can contribute to suppressing false detections with higher accuracy in touch detection of capacitive touch panels. [Brief explanation of the drawing]

[0012] [Figure 1] This is a front view of a display input device according to the first embodiment of the present invention. [Figure 2] This is a block diagram showing an example of the functional configuration of a touch detection device according to the first embodiment of the present invention. [Figure 3] This is a diagram showing a magnified view of a portion of the touch surface. [Figure 4] This figure shows the contents of the detected value frame data. [Figure 5]It is a flowchart showing an operation example of a touch detection device according to the first embodiment of the present invention. [Figure 6] It is a diagram used for explaining the pinpoint mode. [Figure 7] It is a diagram used for explaining the line mode. [Figure 8] It is a diagram showing the transition of the detection value of the point of interest. [Figure 9] It is a diagram showing the transition of the detection value of the point of interest. [Figure 10] It is a block diagram showing a functional configuration example of a touch detection device according to the second embodiment of the present invention. [Figure 11] It is a flowchart showing an operation example of a touch detection device according to the second embodiment of the present invention. [Figure 12] It is a diagram showing the detection values of the points around the point of interest. [Figure 13] It is a diagram showing the detection values of the points around the point of interest. [Figure 14] It is a flowchart showing an operation example of a touch detection device according to the first modification of the second embodiment of the present invention. [Figure 15] It is a block diagram showing a functional configuration example of a touch detection device according to the third embodiment of the present invention. [Figure 16] It is a flowchart showing an operation example of a touch detection device according to the third embodiment of the present invention. [Figure 17] It is a flowchart showing an operation example of a touch detection device according to the first modification of the third embodiment of the present invention. [Figure 18] It is a flowchart showing an operation example of a touch detection device according to the second modification of the third embodiment of the present invention. [[ID=4l]] [Figure 19] It is a flowchart showing an operation example of a touch detection device according to the third modification of the third embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0013] <First Embodiment> Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. Figure 1 is a front view of the display input device 1 according to this embodiment. The display input device 1 comprises a display panel 2 such as a liquid crystal display or an organic EL panel, and a touch panel 3 arranged on top of the display panel 2. The touch panel 3 is provided with a touch surface 4. Below the touch surface 4 in the display input device 1, a switch panel 5 is provided, on which various switches such as a power switch are installed. The display input device 1 has at least the function of displaying an image on the display panel 2 and the function of receiving input by touching the touch surface 4 from the user. The display input device 1 according to this embodiment is installed in the center of the instrument panel of a vehicle, and it is assumed that the touch on the touch surface 4 is performed by the occupant using their finger or other object.

[0014] In the following explanation, with respect to the touch surface 4, as shown in Figure 1, the direction pointing to the left when the display input device 1 is viewed from the front is referred to as "left," the direction pointing to the right when viewed from the front is referred to as "right," the direction pointing upwards when viewed from the front is referred to as "up," and the direction pointing downwards when viewed from the front is referred to as "down."

[0015] Figure 2 is a block diagram showing an example of the functional configuration of the touch detection device 6 along with its related elements. As shown in Figure 2, the touch panel unit 7 is composed of the touch detection device 6 and the touch panel 3. As shown in Figure 2, the touch detection device 6 has a functional configuration that includes a detection value detection unit 10 and a touch detection unit 11. Each of the above functional blocks 10 and 11 can be configured using hardware, a DSP (Digital Signal Processor), or software. For example, when configured using software, the above functional blocks 10 and 11 are actually configured with a computer's CPU, RAM, ROM, etc., and are realized by the operation of a program stored on a recording medium such as RAM, ROM, hard disk, or semiconductor memory. The same applies to the functional blocks of other embodiments.

[0016] The detection value detection unit 10 detects a detection value corresponding to the capacitance for each of the multiple points P scattered on the touch surface 4 of the touch panel 3. The processing of the detection value detection unit 10 will be described in detail below.

[0017] Figure 3 is a diagram showing a portion of the touch surface 4 enlarged in a manner suitable for explanation. The touch panel 3 according to this embodiment is a capacitive touch panel 3 using a mutual capacitance method in which the X electrode and Y electrode are arranged so as to intersect each other. As shown in Figure 3, points P are scattered in a matrix on the touch surface 4 for each pair of capacitively coupled X and Y electrodes (hereinafter simply referred to as "electrodes"). For each point P, the touch panel 3 outputs a detection signal corresponding to the capacitance of the electrode to the detection value detection unit 10 at a predetermined period.

[0018] The detection unit 10 processes as follows for each periodic timing (timing that occurs in each period). First, the detection unit 10 receives the detection signal for each point P from the touch panel 3. Next, for each point P, the detection unit 10 detects a detection value (a detection value corresponding to capacitance) that indicates the amount of change in capacitance based on the input detection signal. The detection value detected by the detection unit 10 can take values ​​on the positive and negative sides of the reference value (baseline of capacitance). In this embodiment, for convenience, the unit of the detection value is referred to as "value," and specific values ​​of the detection value are expressed as, for example, "value of 0" or "value of 50." Also, for the sake of simplicity, the detection value is assumed to take values ​​in the range of "-100 value" to "value of 100," with "value of 0" as the reference value. In other words, the detection unit 10 detects a detection value for each point P that can take values ​​in the range of "-100 value" to "value of 100."

[0019] After detecting a value for all points P, the detection value detection unit 10 updates the detection value frame data 13 stored in the buffer 12 based on the detected value for each point P. The buffer 12 is a primary storage area formed in a work area such as RAM. The detection value frame data 13 is data in which the detected values ​​detected by the detection value detection unit 10 for each point P are associated and registered.

[0020] Figure 4 is a schematic diagram illustrating the contents of a portion of the detected value frame data 13 in a manner suitable for explanation. In Figure 4, it is shown that in the detected value frame data 13, for example, "4 values" are associated and registered with point P-1, and "5 values" are associated and registered with point P-2. In the diagrams used in the following explanation, the detected values ​​for each point P may be shown in the same way as in Figure 4.

[0021] The above is the process that the detection value detection unit 10 executes at periodic timings. As a result of the detection value detection unit 10 performing the above process at each periodic timing, the detected values ​​associated with each point P in the detected value frame data 13 are updated at predetermined intervals with the most recently detected value by the detection value detection unit 10.

[0022] If the detected value detected by the detected value detection unit 10 for a point P changes from being below the touch detection threshold to being above the touch detection threshold, the touch detection unit 11 performs a first determination process to determine whether the detected value detected by the detected value detection unit 10 for a point P is in a first state in which it alternates between positive and negative relative to a reference value over time. If the touch detection unit 11 determines in the first determination process that it is in the first state, it does not detect a touch.

[0023] The operation example of the touch detection unit 11 will be explained in detail below using a flowchart. Flowchart FA in Figure 5 is a flowchart showing the touch detection method by the touch detection device 6, and in particular shows the processing that the touch detection unit 11 executes after a certain periodic timing has arrived. That is, after a certain periodic timing has arrived and the detected value frame data 13 has been updated by the detected value detection unit 10, the touch detection unit 11 executes the processing shown in flowchart FA. Hereafter, the start timing of the processing in flowchart FA will be referred to as periodic timing T0, and each period after periodic timing T0 will be expressed as periodic timing T1, T2, etc. Also, for the sake of explanation, it will be assumed that in the periodic timing immediately preceding periodic timing T0, there are no points P whose detected value is greater than or equal to the touch detection threshold (= for all points P, the detected value is below the touch detection threshold).

[0024] As shown in Figure 5, the touch detection unit 11 of the touch detection device 6 refers to the detection value frame data 13 (the detection value frame data 13 most recently updated by the detection value detection unit 10) that has been expanded into the buffer 12 (step SA1). Next, the touch detection unit 11 determines whether there is one or more points P whose detection value is equal to or greater than the touch detection threshold (step SA2). As described above, in the detection value frame data 13, the detection value most recently detected by the detection value detection unit 10 is registered in association with each point P, so the touch detection unit 11 can recognize the detection value of each point P by referring to the detection value frame data 13.

[0025] The touch detection threshold is set such that when a user touches the touch surface 4 in the normal manner with an object (e.g., a finger), the detected value of the touched point P is equal to or greater than this touch detection threshold. However, the detected value of point P affected by electrostatic noise may also be equal to or greater than the touch detection threshold not only when a user touches the touch surface 4 with an object, but also when electrostatic noise is generated on the touch surface 4.

[0026] If it is determined that there are no points P whose detected value is equal to or greater than the touch detection threshold (Step SA2: NO), the touch detection unit 11 does not detect a touch (Step SA3) and terminates the process. In this case, when the next cycle timing arrives, the touch detection unit 11 executes the process of Step SA1 again. On the other hand, if it is determined that there is one or more points P whose detected value is equal to or greater than the touch detection threshold (Step SA2: YES), the touch detection unit 11 determines the point P with the largest detected value among the points P whose detected value is equal to or greater than the touch detection threshold as the "point of interest PA" (Step SA4). If there is only one point P whose detected value is equal to or greater than the touch detection threshold, that point P is determined to be the point of interest PA.

[0027] In this embodiment, if the detected values ​​for multiple points P are equal to or greater than the touch detection threshold, the point P with the largest detected value is designated as the point of interest PA. However, the point of interest PA may be determined by other methods. Alternatively, the touch detection unit 11 may determine two or more points P as points of interest PA according to predetermined rules, and perform the processing in step SA5 or below for each of the multiple points of interest PA.

[0028] After determining the point of interest PA, the touch detection unit 11 performs a basic discrimination process. More specifically, the touch detection unit 11 determines whether the detected value of the point of interest PA is equal to or greater than the electrostatic noise threshold (> touch detection threshold) (step SA5). The electrostatic noise threshold is defined as a value at which, when a user touches the touch surface 4 in the normal manner with an indicator, the detected value of the touched point P is very unlikely to be equal to or greater than this electrostatic noise threshold. However, if electrostatic noise occurs on or near the touch surface 4, the detected value of the point P affected by the electrostatic noise may be equal to or greater than this electrostatic noise threshold.

[0029] If the touch detection unit 11 determines that the detected value of point PA is above the electrostatic noise threshold (step SA5: YES), it does not detect a touch (step SA3) and terminates the process. This is because it is highly likely that the reason the detected value of point PA is above the touch detection threshold is due to the occurrence of electrostatic noise. On the other hand, if the touch detection unit 11 determines that the detected value of point PA is not above the electrostatic noise threshold (step SA5: NO), it determines whether the distribution of point P, whose detected value is above the distribution identification threshold (≤ touch detection threshold), is in a specific pattern (step SA6). Hereinafter, the distribution of point P, whose detected value is above the distribution identification threshold, will be specifically referred to as the "basic discrimination distribution".

[0030] Step SA6 is performed to prevent touch detection when the basic discrimination distribution pattern is clearly different from the distribution that appears when a user touches the touch surface 4 in the normal way using an indicator. Accordingly, the specific pattern is a distribution that may appear due to electrostatic noise, but is clearly different from the distribution that appears when a user touches the touch surface 4 in the normal way using an indicator. In this embodiment, pinpoint pattern and line pattern are set as specific patterns.

[0031] A pinpoint distribution is one in which there is only one point P (i.e., only the point of interest PA) whose detected value is equal to or greater than the distribution identification threshold. It has been confirmed that such distributions are very likely to originate from electrostatic noise rather than from normal user touch. For example, suppose the touch detection threshold is "70" and the distribution identification threshold is "50". In this case, the basic discrimination distribution shown in Figure 6(A) (however, points other than the point P whose detected value is shown in Figure 6(A) are not considered; this is also true for similar diagrams described later) is a pinpoint distribution. This is because the basic discrimination distribution shown in Figure 6(A) is a distribution composed only of the point of interest PA (detected value: 72). On the other hand, the basic discrimination distribution shown in Figure 6(B) is not a pinpoint distribution. This is because the basic discrimination distribution is a distribution composed of not only the point of interest P-1 but also multiple other points P.

[0032] A line pattern is a state in which a certain number or more points P whose detected value is equal to or greater than the distribution identification threshold are lined up on a single line (a single row extending in the left-right direction). In this embodiment, one line pattern is defined as a state in which 100 or more points P whose detected value is equal to or greater than the distribution identification threshold are lined up on a single line. It has been confirmed that such a state is very likely to originate from electrostatic noise rather than from a normal user touch. For example, suppose the touch detection threshold is "70" and the distribution identification threshold is "50". In this case, the basic discrimination distribution shown in Figure 7 is a line pattern. This is because 100 or more points P whose detected value is equal to or greater than the distribution identification threshold (=50) are lined up on a single line.

[0033] Furthermore, the specific embodiments are not limited to pinpoint embodiments and line embodiments. Similarly, the line embodiments are not limited to the examples provided. In other words, the specific embodiments are simply those distributions that may appear due to electrostatic noise, but which are clearly different from the distributions that appear when a user touches the touch surface 4 in the normal manner using an indicator.

[0034] In step SA6 of flowchart FA in Figure 5, if it is determined that the basic discrimination distribution (the distribution of points P whose detected value is equal to or greater than the distribution identification threshold) is in a specific pattern (step SA6: YES), the touch detection unit 11 does not detect a touch (step SA3) and terminates the process. On the other hand, if it is determined in step SA6 that the basic discrimination distribution is not in a specific pattern (step SA6: NO), the touch detection unit 11 proceeds to step SA7 of the processing procedure.

[0035] Here, the combination of the processing in step SA5 and the processing in step SA6 corresponds to the "basic discrimination process". In this basic discrimination process, the touch detection unit 11 determines whether the detected value of the point of interest PA is equal to or greater than the electrostatic noise threshold (>touch detection threshold), or whether the distribution for basic discrimination (the distribution of points P whose detected value is equal to or greater than the distribution identification threshold (≤touch detection threshold)) is in a specific pattern (hereinafter referred to as the "normal touch deviation state"). If it determines that the normal touch deviation state exists, it does not detect a touch. On the other hand, if the detected value of the point of interest PA is not equal to or greater than the electrostatic noise threshold, and the distribution for basic discrimination is not in a specific pattern (= it is not the normal touch deviation state), the touch detection unit 11 moves the processing procedure to the next step.

[0036] In step SA7, the touch detection unit 11 performs the following process. Specifically, the touch detection unit 11 waits until the period timing T5 arrives, which is 5 periods after the period timing T0. At the time the period timing T5 arrives, it determines whether the detected value of the point of interest PA (i.e., the detected value detected by the detection value detection unit 10 for the point of interest PA at period timing T5) is greater than or equal to the touch detection threshold, or less than or equal to the negative threshold (step SA7).

[0037] In this embodiment, it has been confirmed that when the touch surface 4 is touched in the usual manner by an indicator that is not charged with static electricity or is only partially charged (e.g., a finger), the detected value of the point of interest PA remains above the touch detection threshold for at least 5 periods starting from the period timing T0. Based on this, the significance of "determining whether the detected value of the point of interest PA is above the touch detection threshold" in step SA7 is to determine whether the touch surface 4 was touched in the usual manner by an indicator that is not charged with static electricity (more precisely, whether there is a high probability that it was touched).

[0038] Furthermore, when the touch surface 4 is touched in the normal manner by an electrostatically charged indicator, it has been confirmed that at periodic timing T5, there are cases where the detected value of the point of interest PA is above the touch detection threshold, and cases where the detected value of the point of interest PA is on the negative side and is below the negative threshold set on the negative side. Based on this, the significance of "determining whether the detected value of the point of interest PA is below the negative threshold" in step SA7 is to determine whether the touch surface 4 was touched in the normal manner by an electrostatically charged indicator (more precisely, whether there is a high probability that it was touched).

[0039] In the following, the processing in step SA7 corresponds to the "touch continuation determination process". In the following, the state in which "the detected value of the point of interest PA is equal to or greater than the touch detection threshold, or less than or equal to the negative threshold" is referred to as the "touch continuation state". In the touch continuation determination process, the touch detection unit 11 determines whether or not the touch continuation state is in effect, and only if it determines in the touch continuation determination process that the touch continuation state is in effect, it executes the first determination process described later.

[0040] In this embodiment, the touch detection unit 11 executes the process of step SA7 (touch continuation determination process) at a timing 5 cycles after the period timing T0, but this is merely an example. The timing at which the touch continuation determination process is executed, after how many cycles from the period timing T0, should be appropriately determined based on the results of prior simulations and tests, taking into account the actual time of one cycle and the time required for the basic determination processes of steps SA5 and SA6. The specific value of the negative threshold should also be appropriately determined based on the results of prior simulations and tests, with the aim of determining whether or not there is a possibility that a normal touch has occurred.

[0041] If, in step SA7, it is determined that the detected value of the point of interest PA is neither above the touch detection threshold nor below the negative threshold (i.e., it is determined that the touch is not continuing) (step SA7: NO), the touch detection unit 11 does not detect a touch (step SA3) and terminates the process. On the other hand, if, in step SA7, it is determined that the detected value of the point of interest PA is above the touch detection threshold or below the negative threshold (i.e., it is determined that the touch is continuing) (step SA7: YES), the touch detection unit 11 starts monitoring the change in the detected value of the point of interest PA (hereinafter referred to as "monitoring the change in detected value of the point of interest") (step SA8). In step SA8, the touch detection unit 11 starts counting the number of cycles. After starting the count in step SA8, the touch detection unit 11 repeatedly executes the processes of steps SA9 and SA10 at predetermined intervals until it exits the loop. Hereinafter, the timing of the process in step SA8 will be referred to as the monitoring timing M0, and each cycle starting from monitoring timing M0 will be expressed as monitoring timing M1, M2, and so on.

[0042] In step SA9, the touch detection unit 11 determines whether the monitoring period has ended (step SA9). In step SA9, the touch detection unit 11 determines that the monitoring period has ended if the number of cycles that started counting in step SA8 has reached a predetermined number of monitoring cycles (in this embodiment, 12 cycles). If it is determined that the monitoring period has ended (step SA9: YES), the touch detection unit 11 detects a touch (step SA11) and terminates the process. Detecting a touch means determining that a touch has been made by the user. In other words, in this embodiment, the touch detection unit 11 detects a touch if the first state has not been reached before the monitoring period has elapsed.

[0043] Although details are omitted, when a touch is detected by the touch detection unit 11, the touch detection device 6 or a device connected to the touch detection device 6 performs actions corresponding to the touch position (for example, if the touch position belongs to a specific icon, an action is performed to execute a predetermined process corresponding to that icon).

[0044] On the other hand, if it is determined that the monitoring period has not ended (step SA9: NO), the touch detection unit 11 determines whether or not the "first state in which the detected value of the point of interest PA alternates between positive and negative values ​​as time progresses" has been reached (step SA10). The processing of step SA10 will be described in detail below.

[0045] In this embodiment, the first state means the following: a first upper threshold (<touch detection threshold) with a positive value and a first lower threshold (>negative threshold) with a negative value are predetermined. The first state means any of the following states. (1) At monitoring timing M0, the detected value of the point of interest PA, which exceeds the first upper threshold, temporarily falls below the first lower threshold as time passes before the end of the monitoring period, and then rises above the first upper threshold (hereinafter referred to as "State 1-1"). (2) The detection value of the point of interest PA, which is below the first lower threshold at monitoring timing M0, temporarily rises above the first upper threshold as time progresses before the end of the monitoring period, and then falls below the first lower threshold (hereinafter referred to as "the first-second state").

[0046] Figure 8 is a diagram illustrating an example of the change in the detected value of the point of interest PA over time, starting from monitoring timing M0, in order to explain the 1-1 state. In Figure 8, the horizontal axis represents the passage of time, and the vertical axis represents the detected value. In the example in Figure 8, the first upper threshold is set to "10" and the first lower threshold is set to "-10". This is also the case in Figure 9, which will be described later.

[0047] In Figure 8, at monitoring timing M0, the detected value of the point of interest PA is above the first upper threshold. Then, at monitoring timing M4, four cycles after monitoring timing M0, the detected value of the point of interest PA is below the first lower threshold. Subsequently, at monitoring timing M7, three cycles after monitoring timing M4, the detected value of the point of interest PA is above the first upper threshold. In other words, in the example in Figure 8, the detected value of the point of interest PA, which is above the first upper threshold at monitoring timing M0, temporarily falls below the first lower threshold at monitoring timing M4 as time progresses before the end of the monitoring period, and then becomes above the first upper threshold at monitoring timing M7, thus establishing state 1-1. In the example in Figure 8, the touch detection unit 11 determines that state 1 has been reached during the processing of step SA10 performed at monitoring timing M7.

[0048] Figure 9 is a diagram illustrating an example of the change in the detected value of the point of interest PA over time, starting from monitoring timing M0, in order to explain the first-second state. In Figure 9, at monitoring timing M0, the detected value of the point of interest PA is below the first lower threshold. Then, at monitoring timing M3, three cycles after monitoring timing M0, the detected value of the point of interest PA is above the first upper threshold. Subsequently, at monitoring timing M5, two cycles after monitoring timing M3, the detected value of the point of interest PA is below the first lower threshold. In other words, in the example of Figure 9, the detected value of the point of interest PA, which is below the first lower threshold at monitoring timing M0, becomes above the first upper threshold at monitoring timing M3, and then below the first lower threshold at monitoring timing M5, as time progresses before the end of the monitoring period, thus establishing the first-second state. In the example of Figure 9, the touch detection unit 11 determines that the first state has been reached during the processing of step SA10 performed at monitoring timing M5.

[0049] If step SA10 determines that the first state (either state 1-1 or state 1-2) is not in place (step SA10: NO), the touch detection unit 11 returns to step SA9 and executes the process of step SA9 in the next cycle. On the other hand, if step SA10 determines that the first state (either state 1-1 or state 1-2) is established (step SA10: YES), the touch detection unit 11 does not detect a touch (step SA3) and terminates the process.

[0050] The processing in steps SA8 to SA11 corresponds to the "first determination process". As described above, in the first determination process, the touch detection unit 11 determines whether or not the first state is in place (whether or not the first state was reached during the monitoring period), and if it determines that the first state is in place, it does not detect a touch.

[0051] As described above, in this embodiment, when the detected value for a point P on the touch surface 4 of the touch panel 3 changes from a state where it was below the touch detection threshold to a state where it was above the touch detection threshold, the touch detection device 6 executes a first determination process to determine whether the detected value for that point P is in a first state in which it alternates between positive and negative relative to a reference value over time. If it is determined to be in the first state, the touch is not detected. This provides the following effects.

[0052] The inventors have found that when the detected value of a point P exceeds the touch detection threshold due to electrostatic noise, the detected value at that point P alternates between positive and negative relative to a reference value over time. Based on the above, according to this embodiment, when the detected value of a point P exceeds the touch detection threshold, it is determined whether or not the detected value of that point P is in a first state where it alternates between positive and negative relative to a reference value over time. If it is in the first state, no touch is detected. Therefore, false detections can be suppressed in an accurate manner that reflects the characteristics of the effect that electrostatic noise has on the detected value of each point P.

[0053] In this embodiment, the contents of the first state have been specifically illustrated, but the contents of the first state are not limited to those illustrated. That is, the first state is a state in which the detected value of point P alternates between being positive and negative relative to the reference value as time progresses. Furthermore, the specific values ​​of the monitoring period, the first upper threshold, and the first lower threshold are not limited to the illustrated values.

[0054] <Second Embodiment> Next, a second embodiment will be described. In the following description of the second embodiment, the same reference numerals are used for elements that are the same as in the first embodiment, and their detailed descriptions are omitted. Figure 10 is a block diagram showing an example of the functional configuration of the touch detection device 6A according to this embodiment, along with related elements. As shown in Figure 10, the touch panel unit 7A is composed of the touch detection device 6A and the touch panel 3. As shown in Figure 11, the touch detection device 6A is equipped with a touch detection unit 11A instead of the touch detection unit 11.

[0055] In this embodiment, the touch detection unit 11A, when the detected value detected by the detected value detection unit 10 for one point P changes from a state where it was below the touch detection threshold to a state where it is above the touch detection threshold, executes a second determination process to determine whether the detected values ​​detected by the detected value detection unit 10 at the same time for points P surrounding the one point P are in a second state where they alternately change from positive to negative relative to the reference value outward from the one point P. If it is determined that it is in the second state, the touch is not detected. Below, an example of the operation of the touch detection unit 11A will be described in detail using a flowchart.

[0056] The flowchart FB in Figure 11 is a flowchart showing the touch detection method by the touch detection device 6A according to this embodiment, and in particular shows the processing of the touch detection unit 11A. The touch detection unit 11A according to this embodiment performs the processing shown in the flowchart FB in Figure 11 instead of the processing shown in the flowchart FA in Figure 5. As is clear from comparing Figure 5 and Figure 11, the touch detection unit 11A performs the second discrimination process instead of the first discrimination process according to the first embodiment. The processing of the touch detection unit 11A when mainly performing the second discrimination process will be described below using flowchart FB.

[0057] Referring to Figure 11, if in step SA7 the detected value of the point of interest PA is determined to be equal to or greater than the touch detection threshold, or less than or equal to the negative threshold (i.e., if it is determined that the touch is continuing), the touch detection unit 11A performs the following process. That is, the touch detection unit 11A refers to the detected value frame data 13 in the buffer 12 and determines whether or not it is in the "second state in which the detected value of point P surrounding the point of interest PA alternates between the positive and negative sides as it moves outward from the point of interest PA" (step SB1). The process of step SB1 will be described in detail below. In the following, the processing timing of step SB1 will be referred to as observation timing K0, and each period after observation timing K0 will be expressed as observation timing K1, K2, etc.

[0058] In this embodiment, the second state means the following: a second upper threshold (<touch detection threshold) with a positive value and a second lower threshold (>negative threshold) with a negative value are predetermined. The second state means any of the following states. (1) When the point of interest PA exceeds the second upper threshold at observation timing K0, and when observing the change in the detected value of points P around the point of interest PA in the scanning direction (described later) starting from the point of interest PA, the detected value of point P temporarily falls below the second lower threshold and then rises above the second upper threshold before reaching the upper limit of observations (hereinafter referred to as "state 2-1"). (2) When the point of interest PA falls below the second lower threshold at observation timing K0, and the change in the detected value of points P around the point of interest PA is observed in the scanning direction (described later) starting from the point of interest PA, the detected value of point P temporarily becomes above the second upper threshold and then falls below the second lower threshold before reaching the upper limit of observations (hereinafter referred to as "the second-2 state").

[0059] First, let's explain the scanning direction. Referring to Figure 1, the touch detection unit 11A sets the scanning direction to "right" when the point of interest PA is located in the left region relative to the center line S1 in the left-right direction of the touch surface 4, and to "left" when the point of interest PA is located in the right region. The touch detection unit 11A also sets the scanning direction to "right" (however, it may also be left) when the point of interest PA is located on the center line S1. For example, in Figure 1, when point P-3, located to the left of the center line S1, is the point of interest PA, the scanning direction is set to the right as indicated by arrow Y1, and when point P-4, located to the right of the center line S1, is the point of interest PA, the scanning direction is set to the left as indicated by arrow Y2. However, this is just one example of how to determine the scanning direction, and it may be determined by other methods.

[0060] Figure 12 is a diagram showing the detected values ​​of point P around the point of interest PA, in order to explain the 2-1 state. In Figure 12, point P-Q0 is the point of interest PA, and points P-Q1 to P-Q10 are arranged to the right (= scanning direction) starting from point P-Q0. In the example of Figure 12, the scanning direction is "rightward", the number threshold is "10", the second upper threshold is "value 10", and the second lower threshold is "value -10". The same applies to Figure 13, which will be described later.

[0061] In Figure 12, the detected value at point P-Q0 is "72". The detected value changes as follows as you move from point P-Q0 toward the scanning direction: "50 (point P-Q1)" → "-20 (point P-Q2)" → "-30 (point P-Q3)" → "4 (point P-Q4)" → "25 (point P-Q5)" → "40 (point P-Q6)" → "3 (point P-Q7)" → "-5 (point P-Q8)" → "-14 (point P-Q9)" → "6 (point P-Q10)". Therefore, in the example in Figure 12, when observing the change in the detected value of point P as you move toward the scanning direction starting from point P-Q0, before reaching the upper limit of observations (10), the detected value at point P-Q2 temporarily falls below the second lower threshold, and then at point P-Q5 the detected value becomes above the second upper threshold. Therefore, the state shown in Figure 12 is the 2-1 state.

[0062] Figure 13 is a diagram showing the detected values ​​of point P around point PA to explain state 2-2. In Figure 13, the detected value of point P-Q0 is "-72". The detected values ​​change as follows from point P-Q0 toward the scanning direction: "-30 (point P-Q1)" → "0 (point P-Q2)" → "18 (point P-Q3)" → "40 (point P-Q4)" → "21 (point P-Q5)" → "-9 (point P-Q6)" → "-21 (point P-Q7)" → "-8 (point P-Q8)" → "4 (point P-Q9)" → "15 (point P-Q10)". In the example shown in Figure 13, when observing the change in the detected value of point P in the scanning direction starting from point P-Q0, the detected value at point P-Q3 temporarily exceeds the second upper threshold before reaching the upper limit of observations (10 points), and then at point P-Q7 the detected value falls below the second lower threshold. Therefore, the state shown in Figure 13 is state 2-2.

[0063] If it is determined in step SB1 that the system is in the second state (the 2-1 state or the 2-2 state) (step SB1: YES), the touch detection unit 11A does not detect a touch (step SA3) and terminates the process. On the other hand, if it is determined in step SB1 that the system is not in the second state (step SB1: NO), the touch detection unit 11A detects a touch (step SA11) and terminates the process.

[0064] The processing in step SB1 corresponds to the "second determination process". As described above, in the second determination process, the touch detection unit 11A determines whether or not the second state is in effect, and if it determines that the second state is in effect, it does not detect a touch.

[0065] As described above, in this embodiment, when the detected value detected for the point of interest PA on the touch surface 4 of the touch panel 3 rises from below the touch detection threshold to above the touch detection threshold, the touch detection device 6 performs a second determination process to determine whether the detected values ​​detected at the points P surrounding the point of interest PA by the detection value detection unit 10 at the same time are in a second state in which the values ​​alternately change from positive to negative as they move outward from the point of interest PA. If the touch detection device 6A determines that it is in the second state, it does not detect a touch. This produces the following effects.

[0066] The inventors have found that when the detected value of a point P exceeds the touch detection threshold due to electrostatic noise, the distribution of detected values ​​of points surrounding that point alternates between positive and negative values ​​relative to a reference value as it moves outward from that point. Based on this, according to this embodiment, when the detected value of a point P exceeds the touch detection threshold, it is determined whether the system is in a second state where the distribution of detected values ​​of points surrounding that point alternates between positive and negative values ​​relative to a reference value as it moves outward from that point. If the system is in the second state, no touch is detected. Therefore, false detections can be suppressed in an accurate manner that reflects the characteristics of the effect that electrostatic noise has on the detected value of each point P.

[0067] Furthermore, this embodiment offers the following advantages compared to the first embodiment. In the second embodiment, the touch detection unit 11A can immediately determine whether or not the second state is present based on the content of the detected value frame data 13 at the time the second discrimination process is executed. Therefore, this embodiment makes it possible to detect or not detect a touch at an earlier stage compared to the first embodiment. In the first embodiment, the touch detection unit 11 needs to monitor the temporal change in the detected value of the point of interest PA in order to determine that the first state is present, which means that it takes time to make a determination.

[0068] In this embodiment, the content of the second state is specifically illustrated, but the content of the second state is not limited to what is illustrated. That is, the second state is a state in which the detected values ​​detected by the detection value detection unit 10 at the same timing for points P surrounding one point P alternately change from positive to negative relative to the reference value as you move outward from the one point P. Furthermore, the method for determining the scanning direction and the specific value of the upper limit of observations are not limited to what is illustrated.

[0069] <First modified example of the second embodiment> Next, a first modified example of the second embodiment will be described. The flowchart FC in Figure 14 is a flowchart showing the touch detection method by the touch detection device 6A according to this modified example, and in particular shows the process executed by the touch detection unit 11A. In this modified example, the touch detection unit 11A of the touch detection device 6A executes the process shown in the flowchart FC in Figure 14 instead of the process shown in the flowchart FB in Figure 11. As is clear from comparing Figure 14 and Figure 11, in this modified example, the basic discrimination process and the second discrimination process are swapped. In this modified example as well, the second discrimination process is performed, resulting in the same effect as in the second embodiment.

[0070] Furthermore, this modified version provides the following effect: a second discrimination process is performed prior to the basic discrimination process. As described above, in the second discrimination process, it is immediately determined whether or not the second state is present at the time the process is performed. Therefore, if the touch detection unit 11A determines that the second state is present in the second discrimination process, the basic discrimination process is not performed, and it is decided at this stage not to detect a touch. Based on the above, this modified version makes it possible for the touch detection unit 11A to decide not to detect a touch at an earlier stage compared to the first and second embodiments.

[0071] <Third Embodiment> Next, a third embodiment will be described. In the following description of the third embodiment, the same reference numerals will be used for elements identical to those in the first embodiment, and their detailed descriptions will be omitted. Figure 15 is a block diagram showing an example of the functional configuration of the touch detection device 6B according to this embodiment, along with related elements. As shown in Figure 16, the touch panel unit 7B is composed of the touch detection device 6B and the touch panel 3. As shown in Figure 15, the touch detection device 6B includes a touch detection unit 11B instead of the touch detection unit 11.

[0072] As shown in Figure 15, the touch detection device 6B according to this embodiment includes an environmental noise detection unit 20. The environmental noise detection unit 20 is connected to an environmental noise sensor 21 and detects the magnitude of environmental noise based on the input from the environmental noise sensor 21. Environmental noise is noise that causes a change in the capacitance of point P. In this embodiment, environmental noise is represented by a numerical value, and a larger value indicates that the environmental noise is adversely affecting the capacitance of point P.

[0073] The environmental noise sensor 21 is, for example, a sensor for detecting electrostatic noise provided on the housing of the touch panel 3. In this case, for example, the environmental noise sensor 21 outputs a value to the environmental noise detection unit 20 that indicates the capacitance of one or more capacitors to which a constant voltage is applied (capacitance fluctuates depending on the degree of electrostatic noise generation), and the environmental noise detection unit 20 derives and detects environmental noise based on the input from the environmental noise sensor 21. Alternatively, for example, the environmental noise sensor 21 is a sensor that detects noise that causes fluctuations in the ground of the touch panel 3. Two examples have been given above, but the environmental noise sensor 21 can be any sensor that outputs a value that can derive the magnitude of noise that causes a change in the capacitance of point P.

[0074] In this embodiment, the touch detection unit 11B, when the detected value detected by the detected value detection unit 10 for a point P is equal to or greater than the touch detection threshold, executes an environmental noise-related discrimination process to determine whether the magnitude of the environmental noise detected by the environmental noise detection unit 20 is equal to or greater than a predetermined environmental noise threshold. Only if the environmental noise-related discrimination process determines that the magnitude is not equal to or greater than the environmental noise threshold, does the first discrimination process execute. An example of the operation of the touch detection unit 11B will be described in detail below using a flowchart.

[0075] The flowchart FD in Figure 16 is a flowchart showing the touch detection method by the touch detection device 6B according to this embodiment, and in particular shows the processing of the touch detection unit 11B. The touch detection unit 11B according to this embodiment performs the processing shown in the flowchart FD in Figure 16 instead of the processing shown in the flowchart FA in Figure 5. As is clear from comparing Figure 5 and Figure 16, the touch detection unit 11B performs the processing of step SD1 between step SA6 and step SA7.

[0076] In step SD1, the touch detection unit 11B determines whether the environmental noise detected by the environmental noise detection unit 20 is above a predetermined environmental noise threshold. The situation in which the environmental noise is above the environmental noise threshold means that even if a point P appears on the touch surface 4 with a detected value above the touch detection threshold, the environmental noise is so large that it is highly likely that this was caused by electrostatic noise. The value of the environmental noise threshold is determined based on the results of prior tests and simulations from this perspective.

[0077] If the system determines that the ambient noise is above the ambient noise threshold (step SD1: YES), the touch detection unit 11B does not detect a touch (step SA3). On the other hand, if the system determines that the ambient noise is not above the ambient noise threshold (step SD1: NO), the touch detection unit 11B proceeds to step SA7.

[0078] The processing in step SD1 corresponds to the environmental noise-related discrimination process. The touch detection unit 11B according to this embodiment executes the first discrimination process only when it determines in the environmental noise-related discrimination process that the environmental noise level is not above the environmental noise threshold.

[0079] This embodiment provides the following advantages. Specifically, if the system determines in step SD1 that the environmental noise is above the environmental noise threshold, the touch detection unit 11B decides not to detect a touch without performing the first discrimination process. Therefore, even if a point P appears with a detected value above the touch detection threshold, if there is a very high probability that the cause is environmental noise, the touch detection unit 11B can quickly determine that it is not a touch without going through the first discrimination process.

[0080] <First modified example of the third embodiment> Next, a first modified example of the third embodiment will be described. The flowchart FE in Figure 17 is a flowchart showing the touch detection method by the touch detection device 6B according to this modified example, and in particular shows the process executed by the touch detection unit 11B. In this modified example, the touch detection unit 11B of the touch detection device 6B executes the process shown in the flowchart FE in Figure 17 instead of the process shown in the flowchart FD in Figure 16. As is clear from comparing Figure 17 and Figure 16, in this modified example, the touch detection unit 11B executes the second discrimination process instead of the first discrimination process.

[0081] According to this modified example, since the environmental noise-related discrimination process is performed prior to the second discrimination process, the same effect as in the third embodiment is achieved, and since the second discrimination process is executed in predetermined cases, the same effect as in the second embodiment is achieved.

[0082] <Second modified example of the third embodiment> Next, a second modification of the third embodiment will be described. The flowchart FF in Figure 18 is a flowchart showing the touch detection method by the touch detection device 6B according to this modification, and in particular shows the processing performed by the touch detection unit 11B. In this modification, the touch detection unit 11B of the touch detection device 6B performs the processing shown in the flowchart FF in Figure 18 instead of the processing shown in the flowchart FD in Figure 16. As is clear from comparing Figure 18 and Figure 16, in this modification, the touch detection unit 11B does not perform the environmental noise-related discrimination processing between the basic discrimination processing and the first discrimination processing, but rather performs the environmental noise-related discrimination processing before the basic discrimination processing.

[0083] According to this modified version, the environmental noise-related discrimination process is performed not only before the first discrimination process but also before the basic discrimination process. Therefore, if the environmental noise is determined to be above the environmental noise threshold in step SD1, the touch detection unit 11B decides not to detect a touch without executing both the basic discrimination process and the first discrimination process. Therefore, even if a point P appears with a detected value above the touch detection threshold, if there is a very high probability that the cause is due to environmental noise, the touch detection unit 11B can determine that it is not a touch more quickly than in the third embodiment, without going through the basic discrimination process and the first discrimination process.

[0084] Regarding the second modification of the third embodiment, the first modification of the third embodiment may be applied so that the touch detection unit 11B performs the second discrimination process instead of the first discrimination process.

[0085] <Third modified example of the third embodiment> Next, a third modification of the third embodiment will be described. Flowchart FG in Figure 19 is a flowchart showing the touch detection method by the touch detection device 6B according to this modification, and in particular shows the processing performed by the touch detection unit 11B. In this modification, the touch detection unit 11B of the touch detection device 6B performs the processing shown in flowchart FG in Figure 19 instead of the processing shown in flowchart FD in Figure 16. As is clear from comparing Figure 19 and Figure 16, in this modification, the processing is performed in the order of environmental noise-related discrimination processing → second discrimination processing → touch continuation discrimination processing → basic discrimination processing.

[0086] According to this modified example, the environmental noise-related discrimination process is performed before the second discrimination process and the basic discrimination process. Therefore, if the system determines in step SD1 that the environmental noise is above the environmental noise threshold, the touch detection unit 11B decides not to detect a touch without executing the second discrimination process and the basic discrimination process. Consequently, even if a point P appears with a detected value above the touch detection threshold, if it is highly likely that the cause is due to environmental noise, the touch detection unit 11B can quickly determine that it is not a touch without going through the second discrimination process and the basic discrimination process. Furthermore, since the second discrimination process is executed prior to the basic discrimination process, the same effects as those described in the first modified example of the second embodiment can be achieved.

[0087] Although embodiments of the present invention (including modifications) have been described above, each of these embodiments is merely an example of how the present invention can be implemented, and the technical scope of the present invention should not be interpreted as being limited by these embodiments. In other words, the present invention can be implemented in various forms without departing from its gist or its main features.

[0088] Although the touch panel 3 was designed to be mounted in a vehicle, it is naturally not required to be mounted in a vehicle. For example, the touch panel 3 may be used in a tablet terminal or in a dedicated machine such as a ticket vending machine or ATM. In other words, the technology described in the above embodiment is broadly applicable to a touch detection device 6 that controls a capacitive touch panel 3, or to a touch panel unit 7 that includes both the touch panel 3 and the touch detection device 6.

[0089] Furthermore, the touch detection device 6 and an external device may work together to perform some or all of the processes described as being performed by the functional block of the touch detection device 6 in the first embodiment. In this case, the touch detection device 6 and the external device work together to function as the "touch detection device" within the scope of the claims. As an example, at least a portion of the processing of the touch detection unit 11 may be performed by a cloud server that can communicate with the touch detection device 6 via a network.

[0090] Furthermore, although the touch detection device 6 was described as a device independent of the touch panel 3 in each of the embodiments described above, the touch detection device 6 does not need to be an independent device that can be sold on its own. For example, it may be a circuit or unit mounted in the same housing as the touch panel 3.

[0091] Furthermore, the processes shown in each flowchart may be configured without performing a touch continuation detection process. [Explanation of Symbols]

[0092] 3 Touch panel 6, 6A, 6B Touch detection device 7, 7A, 7B Touch Panel Unit 10 Detected Value Detection Unit 11 Touch detection unit 20 Environmental noise detection unit P Points

Claims

1. A touch detection device for detecting touches on a capacitive touch panel, A detection value detection unit detects a detection value corresponding to the capacitance for each of the multiple points scattered on the touch surface of the touch panel, If the detected value detected by the detection value detection unit for one point changes from a state where it was below the touch detection threshold for detecting a touch to a state where it is above the touch detection threshold, the system includes a first determination process to determine whether the detected value detected by the detection value detection unit for one point is in a first state in which it alternates between positive and negative relative to a reference value over time, or a second determination process to determine whether the detected values ​​detected by the detection value detection unit at the same time for points surrounding the one point are in a second state in which they alternate between positive and negative relative to a reference value moving outward from the one point, and if the first determination process determines that it is in the first state, or if the second determination process determines that it is in the second state, the system includes a touch detection unit that does not detect a touch. A touch detection device characterized by the following features.

2. The touch detection unit is If the detected value detected by the detection value detection unit for the first point is equal to or greater than the touch detection threshold, a basic determination process is performed separately from the first determination process and the second determination process to determine whether the detected value for the first point is equal to or greater than the electrostatic noise threshold (where the electrostatic noise threshold > the touch detection threshold) or whether the distribution of the points whose detected value is equal to or greater than the distribution identification threshold (where the distribution identification threshold ≤ the touch detection threshold) is in a normal touch deviation state that follows a specific pattern. If the basic discrimination process determines that the touch is deviating from the normal touch state, no touch is detected. The touch detection device according to claim 1, characterized in that it is a touch detection device.

3. The touch detection unit is If the detected value detected by the detection value detection unit for the aforementioned point exceeds the touch detection threshold, the basic discrimination process is executed, and if the basic discrimination process determines that the state is a deviation from normal touch, no touch is detected. If the basic determination process determines that the state is not a normal touch deviation, the first determination process or the second determination process is executed. The touch detection device according to claim 2, characterized in that it is a touch detection device.

4. The touch detection unit is If the detected value detected by the detection value detection unit for the first point is equal to or greater than the touch detection threshold, the second determination process is executed, and if the second determination process determines that the second state is met, no touch is detected. If the second determination process determines that the state is not the second state, the basic determination process is executed. The touch detection device according to claim 2, characterized in that it is a touch detection device.

5. The system further includes an environmental noise detection unit that detects the magnitude of environmental noise that causes a change in the capacitance of the aforementioned point. The touch detection unit is If the detected value detected by the detection value detection unit for the aforementioned point one is equal to or greater than the touch detection threshold, the environmental noise detection unit will perform an environmental noise-related discrimination process to determine whether or not the magnitude of the environmental noise detected is equal to or greater than a predetermined environmental noise threshold. The first or second discrimination process is executed only if the environmental noise-related discrimination process determines that the environmental noise level is not above the environmental noise threshold. The touch detection device according to claim 1, characterized in that it is a touch detection device.

6. The touch detection unit is If the detected value detected by the detection value detection unit for the first point is equal to or greater than the touch detection threshold, a basic determination process is executed separately from the first determination process, the second determination process, and the environmental noise-related determination process to determine whether the detected value for the first point is equal to or greater than the electrostatic noise threshold (provided that the electrostatic noise threshold > the touch detection threshold), or whether the distribution of the points whose detected value is equal to or greater than the distribution identification threshold is in a specific manner, which is a normal touch deviation state. If the basic discrimination process determines that the touch is deviating from the normal touch state, no touch is detected. The touch detection device according to claim 5, characterized in that it is a touch detection device.

7. The touch detection unit is If the detected value detected by the detection value detection unit for the aforementioned point one is equal to or greater than the touch detection threshold, the basic discrimination process is executed, and if the basic discrimination process determines that the state is a normal touch deviation, the touch is not detected. If the basic discrimination process determines that the state is not a normal touch deviation, the environmental noise-related discrimination process is executed, and if the environmental noise-related discrimination process determines that the environmental noise threshold is exceeded, the touch is not detected. If the environmental noise-related discrimination process determines that the environmental noise level is not above the environmental noise threshold, the first discrimination process or the second discrimination process is executed. The touch detection device according to claim 6, characterized in that it is a touch detection device.

8. The touch detection unit is If the detected value detected by the detection value detection unit for the aforementioned point exceeds the touch detection threshold, the environmental noise-related discrimination process is executed, and if the environmental noise-related discrimination process determines that it exceeds the environmental noise threshold, the touch is not detected. If the environmental noise-related discrimination process determines that the environmental noise level is not above the environmental noise threshold, the basic discrimination process is executed, and if the basic discrimination process determines that the state deviates from the normal touch state, no touch is detected. If the basic determination process determines that the state is not a normal touch deviation, the first determination process or the second determination process is executed. The touch detection device according to claim 6, characterized in that it is a touch detection device.

9. The touch detection unit is If the detected value detected by the detection value detection unit for the aforementioned point exceeds the touch detection threshold, the environmental noise-related discrimination process is executed, and if the environmental noise-related discrimination process determines that it exceeds the environmental noise threshold, the touch is not detected. If the environmental noise-related discrimination process determines that the environmental noise level is not above the environmental noise threshold, the second discrimination process is executed, and if the second discrimination process determines that the second state is met, touch is not detected. If the second determination process determines that the state is not the second state, the basic determination process is executed. The touch detection device according to claim 6, characterized in that it is a touch detection device.

10. The touch detection unit is If the detected value detected by the detection value detection unit for the first point exceeds the touch detection threshold, a touch continuation determination process is executed at a timing later than the timing at which the detected value exceeds the touch detection threshold to determine whether the touch continuation state is one in which the detected value detected by the detection value detection unit for the first point is either greater than or equal to the touch detection threshold or less than or equal to a negative threshold set on the negative side of the reference value. The first or second determination process is executed only if the touch continuation determination process determines that the touch is in a continuous state. The touch detection device according to claim 1, characterized in that it is a touch detection device.

11. Capacitive touch panel, The touch detection device includes a detection value detection unit that detects a detected value corresponding to capacitance for each of a plurality of points scattered on the touch surface of the touch panel, and a touch detection unit that, when the detected value detected by the detection value detection unit for one point changes from a state below a touch detection threshold to a state above the touch detection threshold, determines whether the detected value detected by the detection value detection unit for that point is in a first state in which it alternates between positive and negative relative to a reference value over time, or determines whether the detected values ​​detected by the detection value detection unit at the same time for points surrounding the one point are in a second state in which they alternate between positive and negative relative to a reference value moving outward from the one point, and if the first determination process determines that it is in the first state, or if the second determination process determines that it is in the second state, does not detect a touch. A touch panel unit characterized by the following features.

12. A touch detection method using a touch detection device that includes a detection value detection unit that detects a detection value corresponding to the capacitance for each of several points scattered on the touch surface of a capacitive touch panel, The touch detection device, when the touch detection unit detects a point and the detected value detected by the detection value detection unit changes from a state where it was below a touch detection threshold to a state where it was above a touch detection threshold, performs a first determination process to determine whether the detected value detected by the detection value detection unit for the point is in a first state in which it alternately changes to a positive and negative side relative to a reference value over time, or performs a second determination process to determine whether the detected values ​​detected by the detection value detection unit at the same time for points surrounding the point are in a second state in which they alternately change to a positive and negative side relative to a reference value outward from the point. The touch detection unit of the touch detection device includes the step of not detecting a touch if it determines in the first determination process that the state is the first state or in the second determination process that the state is the second state. A touch detection method characterized by the following features.

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