Electrostatic coordinate input device and operation determination method in electrostatic coordinate input device

Abstract

The invention provides an electrostatic coordinate input device and an operation determination method in the electrostatic coordinate input device, which can determine the presence or absence of an operation such as contact or approach with high precision according to the distance from an indicator and can suppress misoperation. An electrostatic coordinate input device is provided with: an operation surface; a plurality of sensor electrodes arranged on the back surface side of the operation surface; a measurement circuit that measures the capacitance of each of the plurality of sensor electrodes; and a calculation unit that calculates the position of an indicator on the basis of the plurality of capacitances measured by the measurement circuit, the calculation unit calculating the maximum capacitance between the indicator and the sensor electrode on the basis of the plurality of capacitances. A non-pointing determination threshold value for determining a non-pointing operation that is not a pointing operation of the pointing body is set on the basis of the maximum capacitance, and when the number of capacitances exceeding the non-pointing determination threshold value among the plurality of capacitances exceeds a determination number threshold value, the non-pointing determination threshold value is determined to be a non-pointing operation of the pointing body. It is determined that the operation of the pointing body is the non-pointing operation.

Description

Technical Field

[0001] The present disclosure relates to an electrostatic coordinate input device and an operation determination method in the electrostatic coordinate input device. Background Art

[0002] Conventionally, there has been a sensor controller connected to a matrix electrode including M first electrodes extending in a first direction and N second electrodes extending in a second direction. The sensor controller performs: a finger touch detection step of supplying a prescribed signal to the M first electrodes and detecting a finger touch area indicating an area where a finger touches based on the prescribed signal detected by the N second electrodes; and a full range scanning step of using at least a part of the M first electrodes and at least a part of the N second electrodes to detect an undetected stylus and derive position coordinates of the stylus. Further, the sensor controller performs: a sector scanning step of using a smaller number of the first electrodes than the number of the first electrodes used in the full range scanning step and a smaller number of the second electrodes than the number of the second electrodes used in the full range scanning step to derive position coordinates of a detected stylus; a determination step of determining whether the position coordinates derived in the sector scanning step are included in any of the finger touch areas detected in the finger touch detection step; and an invalidation step of invalidating the position coordinates determined to be included in the determination step. The sensor controller further includes a palm false touch prevention step in which, for one or more finger touch areas detected by the finger touch detection step, invalidation is performed by palm false touch prevention processing based on the size of the area. In the determination step, before performing the palm false touch prevention step, the sensor controller performs processing of determining whether the position coordinates derived in the sector scanning step are included in any of the finger touch areas detected in the finger touch detection step (for example, refer to Patent Document 1).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2021-168217 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] However, a conventional sensor controller (control unit of an input device) does not change a threshold for determining the presence or absence of a touch (contact) according to the distance between the operation surface and an indicator such as a hand. Therefore, it is difficult to accurately determine an operation such as the presence or absence of contact or proximity according to the distance between the operation surface and an indicator such as a hand, and there may be a malfunction.

[0008] Therefore, an object is to provide an electrostatic coordinate input device and an operation determination method in the electrostatic coordinate input device that can accurately determine operations such as contact or approach based on the distance from an indicator and can suppress misoperations.

[0009] Means for Solving the Problem

[0010] An electrostatic coordinate input device according to an embodiment of the present disclosure includes: an operation surface; a plurality of sensor electrodes arranged on the back side of the operation surface; a measurement circuit that measures the electrostatic capacitance of each of the plurality of sensor electrodes; and a calculation unit that calculates the position of an indicator based on the plurality of electrostatic capacitances measured by the measurement circuit. The calculation unit calculates the maximum electrostatic capacitance between the indicator and the sensor electrodes based on the plurality of electrostatic capacitances, sets a non-pointing determination threshold for determining a non-pointing operation that is not a pointing (Japanese: finger pointing) operation of the indicator based on the maximum electrostatic capacitance, and when the number of electrostatic capacitances exceeding the non-pointing determination threshold among the plurality of electrostatic capacitances exceeds a determination number threshold, determines that the operation of the indicator is the non-pointing operation.

[0011] Advantageous Effects of the Invention

[0012] It is possible to provide an electrostatic coordinate input device and an operation determination method in the electrostatic coordinate input device that can accurately determine operations such as contact or approach based on the distance from an indicator and can suppress misoperations. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a diagram showing an example of the configuration of the electrostatic coordinate input device according to the embodiment.

[0014] Figure 2 It is a diagram showing an example of the configuration of the electrostatic coordinate input device according to the embodiment.

[0015] Figure 3 It is a diagram showing an example of the configuration of the electrostatic sensor and the control device of the electrostatic coordinate input device according to the embodiment.

[0016] Figure 4A It is a diagram illustrating an example of a pointing operation and a non-pointing operation.

[0017] Figure 4B It is a diagram illustrating an example of a pointing operation and a non-pointing operation.

[0018] Figure 4C It is a diagram illustrating an example of a pointing operation and a non-pointing operation.

[0019] Figure 5 It is a diagram showing an example of a threshold for distance state determination.

[0020] Figure 6 It is a diagram that summarizes and shows the distance state determined by the electrostatic coordinate input device of the embodiment in relation to the maximum electrostatic capacitance and the previous distance state.

[0021] Figure 7 It is a diagram showing a flowchart of the processing executed by the control device of the electrostatic coordinate input device of the embodiment.

[0022] Figure 8 It is a flowchart showing an example of the distance state determination process.

[0023] Figure 9 It is a diagram showing an example of table data of the threshold value used in the non-pointing operation determination process.

[0024] Figure 10 It is a flowchart showing the non-pointing operation determination process.

[0025] Figure 11A It is a diagram showing an example of the distribution of the electrostatic capacitance detected by the electrostatic sensor.

[0026] Figure 11B It is a diagram showing an example of the distribution of the electrostatic capacitance detected by the electrostatic sensor.

[0027] Figure 11C It is a diagram showing an example of the distribution of the electrostatic capacitance detected by the electrostatic sensor.

[0028] Figure 11D It is a diagram showing an example of the distribution of the electrostatic capacitance detected by the electrostatic sensor.

[0029] Figure 12A It is a diagram showing an example of the operation of the electrostatic coordinate input device of the embodiment.

[0030] Figure 12B It is a diagram showing an example of the operation of the electrostatic coordinate input device of the embodiment.

[0031] Figure 12C It is a diagram showing an example of the operation of the electrostatic coordinate input device of the embodiment.

[0032] Figure 12D It is a diagram showing an example of the operation of the electrostatic coordinate input device of the embodiment.

[0033] Figure 12E It is a diagram showing an example of the operation of the electrostatic coordinate input device of the embodiment.

[0034] Figure 13A It is a diagram showing an example of the operation of the electrostatic coordinate input device of the embodiment.

[0035] Figure 13B This is a diagram showing an operation example of the capacitive coordinate input device according to the embodiment.

[0036] Figure 13C This is a diagram showing an operation example of the capacitive coordinate input device according to the embodiment.

[0037] Figure 13D This is a diagram showing an operation example of the capacitive coordinate input device according to the embodiment.

[0038] Figure 13E This is a diagram showing an operation example of the capacitive coordinate input device according to the embodiment.

[0039] Figure 13F This is a diagram showing an operation example of the capacitive coordinate input device according to the embodiment.

[0040] Figure 14A This is a diagram showing a modified example of the table data of the threshold value used in the non-pointing operation determination process.

[0041] Figure 14B This is a diagram showing a modified example of the table data of the threshold value used in the non-pointing operation determination process.

[0042] Figure 14C This is a diagram showing a modified example of the table data of the threshold value used in the non-pointing operation determination process.

[0043] Figure 15 This is a flowchart showing a modified example of the non-pointing operation determination process. Detailed Embodiment

[0044] Hereinafter, an embodiment of the capacitive coordinate input device to which the present disclosure is applied and an operation determination method in the capacitive coordinate input device will be described.

[0045] <Embodiment>

[0046] Figure 1 and Figure 2 This is a diagram showing an example of the configuration of the capacitive coordinate input device 100 according to the embodiment. Figure 1 This shows a state where the capacitive coordinate input device 100 is in an operating state and the display device 110 displays an input image. When the display device 110 displays an input image, the capacitive coordinate input device 100 is in an input mode state. The input mode is a mode in which operation input can be performed on the capacitive coordinate input device 100. Figure 2 This shows a state where the capacitive coordinate input device 100 is in a standby state and the display device 110 displays a standby image. When the display device 110 displays a standby image, the capacitive coordinate input device 100 is in a power saving mode state. In the standby state, the entire display device 110 is displayed in gray, which is a state with low power consumption.Figure 3 FIG. 1 is a diagram showing an example of the configuration of the electrostatic sensor 120 and the control device 130 of the electrostatic coordinate input device 100. The display device 110 is an example of a display unit, the electrostatic sensor 120 is an example of a detection unit, and the control device 130 is an example of a control unit.

[0047] Hereinafter, an XYZ coordinate system will be defined for explanation. The direction parallel to the X-axis (X direction), the direction parallel to the Y-axis (Y direction), and the direction parallel to the Z-axis (Z direction) are orthogonal to each other. In addition, hereinafter, the -Z direction will be described as the direction approaching the electrostatic sensor 120, and the +Z direction will be described as the direction away from the electrostatic sensor 120. In addition, a top view means viewing from the XY plane. In addition, hereinafter, for the sake of easy understanding of the configuration, the lengths, thicknesses, thicknesses, etc. of the respective parts may be exaggeratedly shown.

[0048] The electrostatic coordinate input device 100 can be, for example, a flat input device configured in a store, a facility, etc. and used by an unspecified number of users, or an input unit of an ATM (Automatic Teller Machine). In addition, it can also be an input unit of a cooking appliance that needs to be kept clean. In addition, the electrostatic coordinate input device 100 can also be a tablet computer, a smartphone, a game machine, etc. used by an individual.

[0049] <Overall Configuration of Electrostatic Coordinate Input Device 100>

[0050] The electrostatic coordinate input device 100 includes a housing 101, a top plate 105, a display device 110, an electrostatic sensor 120, and a control device 130. In Figure 1 and Figure 2 the control device 130 is omitted (see Figure 3 ), but as an example, the control device 130 is disposed inside the housing 101 below the display device 110 and the electrostatic sensor 120. The electrostatic coordinate input device 100 includes Figure 3 the electrostatic sensor 120 and the control device 130 shown in

[0051] <Housing 101 and Top Plate 105>

[0052] The housing 101 is a resin or metal housing that houses the display device 110, the electrostatic sensor 120, and the control device 130. As an example, the display device 110 is disposed below the transparent electrostatic sensor 120 and can be visually recognized through the upper surface 105A of the transparent top plate 105 provided in the opening at the upper part of the housing 101.

[0053] <Types of Operation Methods of Electrostatic Coordinate Input Device 100>

[0054] The electrostatic coordinate input device 100 can operate in two states: a state where an indicating body such as the user's hand is non-contact with the operation surface 105A and a state where an indicating body such as the user's hand is in contact with the operation surface 105A.

[0055] The operation method of the electrostatic coordinate input device 100 includes four operations: an approach operation, a selection operation, a determination operation, and a contact operation. The approach operation, the selection operation, and the determination operation among the four operation methods are operations performed in a state where an indicating body such as the hand is non-contact with the operation surface 105A. The contact operation is an operation performed in a state where an indicating body such as the hand is in contact with the operation surface 105A.

[0056] The electrostatic coordinate input device 100 determines five distance states between an indicating body such as the hand and the operation surface 105A in order to distinguish the four operation methods. The five distance states are a non-detection state, an approach state, a selection state, a determination state, and a contact state. The five distance states include a contact state indicating that the operation surface 105A is in contact with an indicating body such as the hand, and a plurality of non-contact states indicating that the operation surface 105A is not in contact with an indicating body such as the hand. The non-detection state, the approach state, the selection state, and the determination state are non-contact states.

[0057] The non-detection state is a state in which the approach operation, the selection operation, the determination operation, and the contact operation are not performed. The approach state, the selection state, the determination state, and the contact state are states in which the approach operation, the selection operation, the determination operation, and the contact operation are performed, respectively. When determining the operation method, the electrostatic coordinate input device 100 uses a plurality of electrostatic capacitance thresholds. As the contact state, the determination state, the selection state, the approach state, and the non-detection state are reached, the position of an indicating body such as the hand moves away from the operation surface 105A.

[0058] In addition, the electrostatic coordinate input device 100 is an input device that operates by a user performing a pointing operation. The pointing operation refers to an operation performed by holding a finger substantially perpendicular to the operation surface 105A. The number of fingers used in the pointing operation may be multiple, but preferably one.

[0059] When performing such a pointing operation, when the finger is not substantially perpendicular to the operation surface 105A, the entire palm approaches the operation surface 105A, and the value of the electrostatic capacitance detected by the electrostatic coordinate input device 100 changes significantly. Therefore, the electrostatic coordinate input device 100 determines whether the pointing operation is correctly performed.

[0060] Hereinafter, an operation method in which the pointing operation is not performed correctly and which is typically performed by the entire palm is referred to as a non-pointing operation. The electrostatic coordinate input device 100 determines whether the operation of the user is a pointing operation or a non-pointing operation. Then, when the pointing operation is continuously detected a specified number of times (three times as an example), the electrostatic coordinate input device 100 determines that the pointing operation has been performed. In addition, when the non-pointing operation is continuously detected a specified number of times (three times as an example), the electrostatic coordinate input device 100 determines that the non-pointing operation has been performed. Determining the operation method when the pointing operation or the non-pointing operation is continuously performed a specified number of times is to prevent misjudgment of the operation method in the case of sudden noise or the like. Details will be described later, and four operation methods will be described here.

[0061] In addition, hereinafter, the case where the user operates with the hand H as an example of the indicator will be described. Hereinafter, operating (approaching operation, selecting operation, determining operation, or contact operation) with the hand H based on the pointing operation or the non-pointing operation is simply expressed as operating (approaching operation, selecting operation, determining operation, or contact operation) with the hand H.

[0062] The approaching operation refers to an operation in which the hand H approaches the operation surface 105A without touching the operation surface 105A of the electrostatic coordinate input device 100, and is an operation for switching the electrostatic coordinate input device 100 from Figure 2 the standby state shown to Figure 1 the operation state shown.

[0063] The selecting operation refers to an operation in which, starting from the state where the approaching operation has been performed, the hand H further approaches the operation surface 105A without touching the operation surface 105A of the electrostatic coordinate input device 100 to select a GUI button displayed on the display device 110.

[0064] The determining operation refers to an operation in which, starting from the state where the selecting operation has been performed, the hand H further approaches the operation surface 105A without touching the operation surface 105A of the electrostatic coordinate input device 100 to determine the operation input for the selected GUI button. The determining operation performs the operation input non-contactingly, which means that the hand H does not touch the operation surface 105A and operates the electrostatic coordinate input device 100 non-contactingly. The operation input performed through the non-contact selecting operation and determining operation can also be referred to as hover input or touchless input.

[0065] The contact operation refers to an operation in which, starting from the state where the selecting operation has been performed, the hand H further approaches the operation surface 105A of the electrostatic coordinate input device 100 and touches the operation surface 105A to determine the operation input for the selected GUI button. The contact operation can also be referred to as touch input.

[0066] <Display device 110>

[0067] As an example, the display device 110 is a liquid crystal display, an organic EL (Electroluminescence) display, or the like. The display device 110 is used to implement the display of a GUI (Graphic User Interface). The display device 110 displays an image of the GUI button 111, a cursor, and an image of the input content display unit 115 that displays the input content. The GUI button 111 is an example of an operation unit, and is arranged in a matrix shape in a top view as an example. In addition, as an example, the GUI button 111 is a circular shape imitating a button.

[0068] As an example, Figures 1 to 3 A total of 45 GUI buttons 111 are shown, that is, 26 GUI buttons 111 for letters, 15 GUI buttons 111 in the form of numeric keys such as numbers, and 4 GUI buttons 111 including a menu key (the key with three lines in the upper left), a CapsLock key, a backspace key (upper right), and an enter key (lower right). The 45 GUI buttons 111 are arranged in 5 rows in the Y direction and 11 rows in the X direction. The rows extend along the X direction, and the Y extends along the column direction. In addition, the GUI buttons 111 are not limited to letters, numbers for numeric keys, etc., and may also be characters, marks, etc. in other languages.

[0069] In addition, here, a method of displaying a total of 45 GUI buttons 111 by the display device 110 will be described. However, the electrostatic coordinate input device 100 may also have an operation unit on which letters, numbers, or marks, etc. are printed on the top plate 105, instead of all or at least a part of the 45 GUI buttons 111. For example, a backlight may be provided on the back side of the top plate 105 to make the operation unit on which letters, numbers, or marks, etc. are printed transmissive. Also, the backlight may be turned off when the electrostatic coordinate input device 100 is in a standby state, and the backlight may be turned on when the electrostatic coordinate input device 100 switches to an input mode to illuminate the letters, numbers, or marks, etc. of the operation unit of the top plate 105. In addition, in this case, in order to display the input content, a liquid crystal display, an organic EL display, etc. may be provided only in a part of the input content display unit 115.

[0070] <Electrostatic sensor 120>

[0071] The electrostatic sensor 120 is overlapped and arranged on the display device 110, as Figure 3As shown, there are a plurality of sensor electrodes 121X extending in the X direction and a plurality of sensor electrodes 121Y extending in the Y direction. The sensor electrodes 121X and 121Y are examples of the electrodes of the detection unit, and are connected to the control device 130 via wirings 122X and 122Y respectively. As an example, such an electrostatic sensor 120 can be a sensor in which a transparent conductive film such as ITO (Indium Tin Oxide) is formed on the surface of a transparent glass and patterned into the sensor electrodes 121X, 121Y and the wirings 122X, 122Y. The electrostatic capacitance detected by the electrostatic sensor 120 is input to the control device 130. The electrostatic capacitance detected by the electrostatic sensor 120 is an example of the detection result of the electrostatic sensor 120.

[0072] In Figure 3 it, as an example, a plurality of sensor electrodes 121X and a plurality of sensor electrodes 121Y are shown. The intervals between the sensor electrodes 121X and between the sensor electrodes 121Y are narrower than the intervals between the GUI buttons 111.

[0073] The plurality of sensor electrodes 121X are scanned row by row, and the plurality of sensor electrodes 121Y are scanned column by column. The AD conversion unit 132 converts the electrostatic capacitance at the plurality of intersections of the plurality of sensor electrodes 121X and the plurality of sensor electrodes 121Y into digital values. The counter 133 counts the change amount of the output of the AD conversion unit 132 and outputs the difference value ΔAD at each intersection. In addition, by the interpolation method, the resolution can also be improved compared with the intervals between the sensor electrodes 121X and between the sensor electrodes 121Y. In this case, the intervals between the sensor electrodes 121X and between the sensor electrodes 121Y may also be wider than the intervals between the GUI buttons 111. Additionally, although not shown in the figure, in the case of using the interpolation method, it may also be a one-to-one correspondence between the GUI buttons 111 and the sensor electrodes of the same size as the GUI buttons 111.

[0074] As an example, the position in the XY coordinates of the hand H detected by the electrostatic coordinate input device 100 using the electrostatic sensor 120 is the XY coordinates where the electrostatic capacitance is the largest in the area where the hand H exists. In addition, the position of the hand H in the Z direction detected by the electrostatic coordinate input device 100 using the electrostatic sensor 120 is a value inversely proportional to the electrostatic capacitance detected by the electrostatic sensor 120. Therefore, obtaining the position of the hand H in the Z direction is synonymous with obtaining the electrostatic capacitance between the hand H and the electrostatic sensor 120. As an example, the electrostatic coordinate input device 100 determines the position of the hand H in the Z direction based on the electrostatic capacitance between the hand H and the electrostatic sensor 120. However, hereinafter, in cases where it is easier to understand by explaining the position of the hand H in the Z direction, the position of the hand H in the Z direction will be described.

[0075] <Control device 130>

[0076] The control device 130 is implemented 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.

[0077] The control device 130 has a main control unit 131, an AD (Analog to Digital) conversion unit 132, a counter 133, a calculation unit 134, an operation control unit 135, a display control unit 136, and a memory 137. The main control unit 131, the AD conversion unit 132, the counter 133, the calculation unit 134, the operation control unit 135, and the display control unit 136 represent the functions of the program executed by the control device 130 as functional blocks. In addition, the memory 137 functionally represents the memory of the control device 130.

[0078] The main control unit 131 is a processing unit that overall controls the processing of the control device 130 and executes processing other than the processing executed by the AD conversion unit 132, the counter 133, the calculation unit 134, the operation control unit 135, and the display control unit 136. For example, the main control unit 131 scans the plurality of sensor electrodes 121X and the plurality of sensor electrodes 121Y.

[0079] The AD conversion unit 132 converts the output of the electrostatic sensor 120 into a digital value. The output of the AD conversion unit 132 is the detected value of the electrostatic capacitance at each intersection of the sensor electrodes 121X and 121Y of the electrostatic sensor 120. The counter 133 counts and outputs the difference value of the output of the AD conversion unit 132 with respect to the reference value. The difference value is the count value of the change amount of the output with respect to the reference value. Hereinafter, it is denoted as the difference value ΔAD. The reference value is the electrostatic capacitance at each intersection of the sensor electrodes 121X and 121Y when there is no finger around the sensor electrodes 121X and 121Y. The difference value ΔAD is the electrostatic capacitance between each intersection of the sensor electrodes 121X and 121Y and the finger.

[0080] The difference value ΔAD is obtained for each intersection. The AD conversion unit 132 converts the electrostatic capacitance at each intersection of the sensor electrodes 121X and 121Y into a digital value, and the counter 133 counts the change amount of the output of the AD conversion unit 132 with respect to the reference value and outputs the difference value ΔAD for each intersection.

[0081] The calculation unit 134 determines the position of the hand H in the XY coordinates and the position of the hand H in the Z direction from the operation surface 105A based on the difference value ΔAD output from the counter 133. The calculation unit 134 determines the distance state between the hand H and the operation surface 105A using the proximity capacitance threshold, selection capacitance threshold, determination capacitance threshold, and contact capacitance threshold described later. As described above, the distance state between the hand H and the operation surface 105A includes a non-detection state, a proximity state, a selection state, a determination state, and a contact state.

[0082] The motion control unit 135 controls the operation of the electrostatic coordinate input device 100 based on the position of the hand H determined by the calculation unit 134. The display control unit 136 controls the display of the display device 110 based on the position of the hand H determined by the calculation unit 134. The memory 137 stores programs, data, etc. used when the main control unit 131, the calculation unit 134, the motion control unit 135, and the display control unit 136 execute processing. In addition, the memory 137 stores data indicating the number of rows and columns of the sensor electrodes 121X and 121Y.

[0083] <Pointing operation and non-pointing operation>

[0084] Figures 4A to 4C It is a diagram showing an example of a pointing operation and a non-pointing operation. Figures 4A to 4C It shows positions corresponding to the first threshold TH1 and the second threshold TH2 for determining the presence or absence of the hand H by the electrostatic sensor 120. Since the second threshold TH2 is larger than the first threshold TH1, the position corresponding to the second threshold TH2 is closer to the operation surface 105A than the position corresponding to the first threshold TH1. Using such first threshold TH1 and second threshold TH2 to determine the size of the hand H is equivalent to measuring the cross-sectional area of the hand H.

[0085] In Figure 4A It shows a state where the fingertip FT of the hand H approaches the operation surface 105A of the top plate 105 perpendicularly to perform a pointing operation. The electrostatic coordinate input device 100 determines whether the pointing operation based on the fingertip FT is performed with the projected area of the hand H from the front end of the fingertip FT of the hand H to a position separated by a predetermined distance, or whether the non-pointing operation is performed with the palm without extending the finger. In the case where the pointing operation is performed as in Figure 4A The electrostatic coordinate input device 100 can determine that the pointing operation based on the fingertip FT is performed.

[0086] In Figure 4BThe figure shows a state where a non-pointing operation is performed by bringing the hand H close to the operation surface 105A of the top plate 105 while holding all fingers without extending them. In such a case, since the projected area of the hand H at the position corresponding to the first threshold TH1 becomes larger, the capacitive coordinate input device 100 can determine that a non-pointing operation has been performed.

[0087] In Figure 4C The figure shows a state where a non-pointing operation is performed by bringing the fingertip FT of the hand H close to the operation surface 105A of the top plate 105 obliquely. Although one finger points to the operation surface 105A, the fingertip FT is inclined with respect to the operation surface 105A and the palm also approaches the operation surface 105A. Therefore, the projected area of the hand H at the position corresponding to the first threshold TH1 becomes larger. Accordingly, the capacitive coordinate input device 100 can determine that a non-pointing operation has been performed.

[0088] <Threshold for distance state determination>

[0089] Figure 5 This is a diagram showing an example of the threshold for distance state determination. Figure 5 This is a diagram showing the thresholds for determining five distance states: non-detection state, approach state, selection state, determination state, and contact state.

[0090] In Figure 5 For the five distance states, the turn-on threshold and the turn-off threshold are shown respectively. The turn-on threshold is the threshold used when determining whether each distance state is met. When the maximum electrostatic capacitance detected by the electrostatic sensor 120 exceeds the turn-on threshold, the distance state becomes the distance state corresponding to that turn-on threshold. In addition, the turn-off threshold is the threshold used when determining whether each distance state is no longer met. When the maximum electrostatic capacitance detected by the electrostatic sensor 120 becomes below the turn-off threshold, the distance state no longer meets the distance state corresponding to that turn-off threshold. Furthermore, for each distance state, the turn-on threshold is set to an electrostatic capacitance larger than the turn-off threshold, and hysteresis is provided to stabilize the distance state.

[0091] For the non-detection state, no turn-on threshold and turn-off threshold are set. The turn-on threshold for the approach state is 26, and the turn-off threshold is 19. The turn-on threshold for the selection state is 103, and the turn-off threshold is 88. The turn-on threshold for the determination state is 273, and the turn-off threshold is 226. The turn-on threshold for the contact state is 1153, and the turn-off threshold is 961. These values are the values obtained by digitally converting the electrostatic capacitance detected by the electrostatic sensor 120 into count values.

[0092] The turn-on threshold and the turn-off threshold are set such that the ranges between the turn-on thresholds and the turn-off thresholds for the approach state, the selection state, the determination state, and the contact state do not overlap with each other.

[0093] The electrostatic coordinate input device 100 uses Figure 5 the turn-on threshold and turn-off threshold shown in the figure, and determines the distance state in the current process according to the distance state in the previous process (the previous control cycle). Figure 6 The determination process is summarized below.

[0094] Figure 6 It is a graph that summarizes and shows the distance states determined by the electrostatic coordinate input device 100 in relation to the maximum electrostatic capacitance and the previous distance state.

[0095] As Figure 6 shown in the figure, when the maximum electrostatic capacitance is 1154 or more, regardless of the previous distance state, the current distance state is determined to be the contact state.

[0096] In addition, when the maximum electrostatic capacitance is 962 or more and 1153 or less, and the previous distance state is the contact state, the current distance state is determined to be the contact state.

[0097] In addition, when the maximum electrostatic capacitance is 962 or more and 1153 or less, and the previous distance state is below the determined state, it is determined that the current distance state is the determined state. Below the determined state means any one of the distance states of non-detection state, approach state, selection state, or determined state.

[0098] In addition, when the maximum electrostatic capacitance is 274 or more and 961 or less, regardless of the previous distance state, the current distance state is determined to be the determined state.

[0099] In addition, when the maximum electrostatic capacitance is 227 or more and 273 or less, and the previous distance state is above the determined state, it is determined that the current distance state is the determined state. Above the determined state means any one of the distance states of contact state or determined state.

[0100] In addition, when the maximum electrostatic capacitance is 227 or more and 273 or less, and the previous distance state is below the selection state, it is determined that the current distance state is the selection state. Below the selection state means any one of the distance states of non-detection state, approach state, or selection state.

[0101] In addition, when the maximum electrostatic capacitance is 104 or more and 226 or less, regardless of the previous distance state, the current distance state is determined to be the selection state.

[0102] In addition, when the maximum electrostatic capacitance is 89 or more and 103 or less, and the previous distance state is at or above the selection state, the current distance state is determined to be the selection state. Being at or above the selection state means that the distance state is any one of the contact state, the determination state, or the selection state.

[0103] In addition, when the maximum electrostatic capacitance is 89 or more and 103 or less and the previous distance state is at or below the approach state, the current distance state is determined to be the approach state. Being at or below the approach state means that the distance state is any one of the non-detection state or the approach state.

[0104] In addition, when the maximum electrostatic capacitance is 27 or more and 88 or less, regardless of the previous distance state, the current distance state is determined to be the approach state.

[0105] In addition, when the maximum electrostatic capacitance is 20 or more and 26 or less and the previous distance state is at or above the approach state, the current distance state is determined to be the approach state. Being at or above the approach state means that the distance state is any one of the contact state, the determination state, the selection state, or the approach state.

[0106] In addition, when the maximum electrostatic capacitance is 20 or more and 26 or less and the previous distance state is the non-detection state, the current distance state is determined to be the non-detection state.

[0107] In addition, when the maximum electrostatic capacitance is 0 or more and 19 or less, regardless of the previous distance state, the current distance state is determined to be the non-detection state.

[0108] <Overall Processing>

[0109] Figure 7 It is a diagram showing a flowchart of the processing executed by the control device 130 of the electrostatic coordinate input device 100. Figure 7 The flowchart shown is called and executed by an application software (not shown). If the application software is in a state of waiting for input, Figure 7 the flowchart shown is repeatedly executed from start to end at a prescribed control cycle.

[0110] When the control device 130 starts (beginning) the processing, the calculation unit 134 acquires the electrostatic capacitance of each electrode (each of the sensor electrodes 121X and 121Y) (step S1).

[0111] The calculation unit 134 calculates the position (XY coordinates) of the hand H (step S2). The position (XY coordinates) of the hand H is the position of the detection point of the maximum electrostatic capacitance among the electrostatic capacitances acquired in step S1.

[0112] The calculation unit 134 determines the distance state between the fingertip FT and the operation surface 105A based on the maximum capacitance obtained in step S2 (step S3). The process of step S3 is a subroutine process for determining the distance state, which will be described later. Through the process of step S3, the distance state between the hand H and the operation surface 105A is determined as any one of the distance states. Figure 8 which will be described later. Through the process of step S3, the distance state between the hand H and the operation surface 105A is determined as any one of the distance states.

[0113] The calculation unit 134 performs a non-pointing operation determination to determine whether a non-pointing operation is being performed (step S4). The process of step S4 is a subroutine process, which will be described later. Through the process of step S4, it is determined whether a non-pointing operation has been performed by the hand H. Figure 8 which will be described later. Through the process of step S4, it is determined whether a non-pointing operation has been performed by the hand H.

[0114] The calculation unit 134 outputs data representing the position (XY coordinates) of the hand H, the maximum capacitance, the distance state, and the presence or absence of a non-pointing operation (step S5).

[0115] After the calculation unit 134 finishes the process of step S5, it ends a series of processes (ends).

[0116] <Distance state determination process>

[0117] Figure 8 is a flowchart showing an example of the distance state determination process. Figure 8 The process shown is Figure 7 the subroutine process of step S3.

[0118] When starting the distance state determination process, the calculation unit 134 determines whether the maximum capacitance obtained in step S2 exceeds 1153 (step S31). This is to determine whether it is in a contact state.

[0119] If the calculation unit 134 determines that the maximum capacitance exceeds 1153 (S31: yes), it determines that the distance state is a contact state (step S31A). When the calculation unit 134 finishes the process of step S31A, it ends the distance state determination process (subroutine process) and makes the flow enter step S4.

[0120] If the calculation unit 134 determines in step S31 that the maximum capacitance does not exceed 1153 (S31: no), it determines whether the maximum capacitance obtained in step S2 exceeds 961 (step S32).

[0121] If the calculation unit 134 determines that the maximum capacitance exceeds 961 (S32: yes), it determines whether the previous distance state was a contact state (step S32A).

[0122] If the calculation unit 134 determines that the previous distance state is the contact state (S32A: Yes), the process proceeds to step S31A, and it is determined that the distance state is the contact state (step S31A). After the calculation unit 134 finishes the processing of step S31A, a series of processing is ended (End).

[0123] When the calculation unit 134 determines in step S32 that the maximum electrostatic capacitance obtained in step S2 does not exceed 961 (S32: No), or when it determines in step S32A that the previous distance state is not the contact state (S32A: No), it is determined whether the maximum electrostatic capacitance obtained in step S2 exceeds 273 (step S33).

[0124] If the calculation unit 134 determines that the maximum electrostatic capacitance exceeds 273 (S33: Yes), it is determined that the distance state is the determined state (step S33A). After the calculation unit 134 finishes the processing of step S33A, a series of processing is ended (End).

[0125] If the calculation unit 134 determines in step S33 that the maximum electrostatic capacitance does not exceed 273 (S33: No), it is determined whether the maximum electrostatic capacitance obtained in step S2 exceeds 226 (step S34).

[0126] If the calculation unit 134 determines that the maximum electrostatic capacitance exceeds 226 (S34: Yes), it is determined whether the previous distance state is the contact state or the determined state (step S34A).

[0127] If the calculation unit 134 determines that the previous distance state is the contact state or the determined state (S34A: Yes), it is determined that the distance state is the determined state (step S34B). After the calculation unit 134 finishes the processing of step S34B, a series of processing is ended (End).

[0128] When the calculation unit 134 determines in step S34 that the maximum electrostatic capacitance does not exceed 226 (S34: No), or when it determines in step S34A that the previous distance state is not either the contact state or the determined state (S34A: No), it is determined whether the maximum electrostatic capacitance obtained in step S2 exceeds 103 (step S35). That the previous distance state is not the determined state means that the previous distance state is the selection state or below.

[0129] If the calculation unit 134 determines that the maximum electrostatic capacitance exceeds 103 (S35: Yes), it is determined that the distance state is the selection state (step S35A). After the calculation unit 134 finishes the processing of step S35A, a series of processing is ended (End).

[0130] If the calculation unit 134 determines in step S35 that the maximum capacitance does not exceed 103 (S35: No), it determines whether the maximum capacitance obtained in step S2 exceeds 88 (step S36).

[0131] If the calculation unit 134 determines that the maximum capacitance exceeds 88 (S36: Yes), it determines whether the previous distance state is any one of the contact state, the determination state, or the selection state (step S36A).

[0132] If the calculation unit 134 determines that the previous distance state is any one of the contact state, the determination state, or the selection state (S36A: Yes), it determines that the distance state is the selection state (step S36B). After the calculation unit 134 finishes the process of step S36B, it ends a series of processes (End).

[0133] When the calculation unit 134 determines in step S36 that the maximum capacitance does not exceed 88 (S36: No), or when it determines in step S36A that the previous distance state is not any one of the contact state, the determination state, and the selection state (S36A: No), it determines whether the maximum capacitance obtained in step S2 exceeds 26 (step S37). That the previous distance state is not any one of the contact state, the determination state, and the selection state means that the previous distance state is the approach state or below.

[0134] If the calculation unit 134 determines that the maximum capacitance exceeds 26 (S37: Yes), it determines that the distance state is the approach state (step S37A). After the calculation unit 134 finishes the process of step S37A, it ends a series of processes (End).

[0135] If the calculation unit 134 determines in step S37 that the maximum capacitance does not exceed 26 (S37: No), it determines whether the maximum capacitance obtained in step S2 exceeds 19 (step S38).

[0136] If the calculation unit 134 determines that the maximum capacitance exceeds 19 (S38: Yes), it determines whether the previous distance state is any one of the contact state, the determination state, the selection state, or the approach state (step S38A).

[0137] If the calculation unit 134 determines that the previous distance state is the approach state (S38A: Yes), it determines that the distance state is the approach state (step S38B). After the calculation unit 134 finishes the process of step S38B, it ends a series of processes (End).

[0138] When the calculation unit 134 determines in step S38 that the maximum capacitance does not exceed 19 (S38: No), or when it determines in step S38A that the previous distance state is not any of the contact state, determination state, selection state, and approach state (S38A: No), it determines that the distance state is a non-detection state (step S39). After the calculation unit 134 finishes the process of step S39, it ends a series of processes (ends).

[0139] <Non-pointing operation determination process>

[0140] Figure 9 It is a diagram showing an example of table data of thresholds used in the non-pointing operation determination process. The thresholds used in the non-pointing operation determination process are the non-pointing determination threshold, the pointing determination threshold, and the determination count threshold. The non-pointing determination threshold, the pointing determination threshold, and the determination count threshold are set respectively for the non-detection state, approach state, selection state, determination state, and contact state.

[0141] The non-pointing determination threshold is a threshold for determining a non-pointing operation based on the maximum capacitance detected by the electrostatic sensor 120. The pointing determination threshold is a threshold for determining a pointing operation based on the maximum capacitance detected by the electrostatic sensor 120. The determination count threshold is a threshold used when discriminating between non-pointing operations and pointing operations.

[0142] The non-pointing determination threshold is a threshold for determining whether a non-pointing operation has been performed based on the capacitance detected by the electrostatic sensor 120 in each of the non-detection state, approach state, selection state, determination state, and contact state. If the number of detection points where the capacitance exceeds the non-pointing determination threshold exceeds the determination count threshold, it is determined that a non-pointing operation has been performed.

[0143] The pointing determination threshold is a threshold for determining whether a pointing operation has been performed based on the capacitance detected by the electrostatic sensor 120 in each of the non-detection state, approach state, selection state, determination state, and contact state. If the number of detection points where the capacitance exceeds the pointing determination threshold is below the determination count threshold, it is determined that a pointing operation has been performed.

[0144] As described above, the determination count threshold is a threshold for comparing with the number of detection points where the capacitance exceeds the pointing determination threshold when determining that a non-pointing operation or a pointing operation has been performed. The value of the determination count threshold represents the number of detection points of the electrostatic sensor 120.

[0145] As Figure 9As shown, the non-pointing determination threshold is set to be equal in the non-detection state and the approaching state, but increases as the state changes from the non-detection state and the approaching state to the selection state, the determination state, the contact state, and the operating state where the hand H approaches the operation surface 105A. More specifically, it is set to 60 in the non-detection state and the approaching state, 90 in the selection state, 220 in the determination state, and 2500 in the contact state. In this way, the shorter the distance represented by the multiple distance states, the larger the value set for the non-pointing determination threshold.

[0146] In addition, the pointing determination threshold is equal to each other in the non-detection state, the approaching state, the selection state, and the determination state, and is set to 50, and is set to 2000 in the contact state.

[0147] As Figure 9 shown, the non-pointing determination threshold in the contact state is larger than the non-pointing determination thresholds in the multiple non-contact states (non-detection state, approaching state, selection state, and determination state), and the pointing determination threshold in the contact state is larger than the pointing determination thresholds in the multiple non-contact states. In addition, the determination number threshold in the contact state is smaller than the determination number thresholds in the multiple non-contact states (non-detection state, approaching state, selection state, determination state).

[0148] Figure 10 is a flowchart showing the non-pointing operation determination process. Figure 8 The process shown is Figure 7 the subroutine process of step S4 of

[0149] When starting the non-pointing operation determination process, the calculation unit 134 sets the non-pointing operation threshold, the pointing operation threshold, and the determination number threshold based on the table data of the thresholds shown according to the distance state (step S41). Figure 9 shown.

[0150] The calculation unit 134 determines whether the previous operation state is a pointing operation (step S42).

[0151] If the calculation unit 134 determines that the variable "operation state" is "pointing operation" (S42: yes), it determines whether the number of detection points where the electrostatic capacitance exceeds the non-pointing operation threshold exceeds the determination number threshold (step S43A). Step S43A is a process for determining whether a non-pointing operation has been performed.

[0152] If the calculation unit 134 determines that the number of detection points where the electrostatic capacitance exceeds the non-pointing operation threshold does not exceed the determination count threshold (S43A: No), it resets the non-pointing operation count to 0 times (step S44A). The non-pointing operation count indicates the number of times that a non-pointing operation is tentatively determined to have been performed by determining "Yes" in step S43A. After the calculation unit 134 finishes the process of step S44A, it ends a series of processes (End).

[0153] If the calculation unit 134 determines in step S43A that the number of detection points where the electrostatic capacitance exceeds the non-pointing operation threshold exceeds the determination count threshold (S43A: Yes), it increments the non-pointing operation count (step S45A).

[0154] The calculation unit 134 determines whether the non-pointing operation count is 3 or more (step S46A).

[0155] If the calculation unit 134 determines that the non-pointing operation count is not 3 or more (S46A: No), it ends a series of processes (End).

[0156] If the calculation unit 134 determines in step S46A that the non-pointing operation count is 3 or more (S46A: Yes), it changes the variable "operation state" to "non-pointing operation" (step S47A). If it is not determined as "Yes" in step S43A three times in a row, the non-pointing operation count will not reach 3.

[0157] Therefore, when it is determined three times in a row in step S43A that the number of detection points where the electrostatic capacitance exceeds the non-pointing operation threshold exceeds the determination count threshold (S43A: Yes), it is determined that the operation of the hand H is a non-pointing operation. In the case of sudden noise generation or the like, in order not to misjudge the operation method, when it is determined three times in a row that the number of detection points where the electrostatic capacitance exceeds the non-pointing operation threshold exceeds the determination count threshold (S43A: Yes), it is determined that the operation of the hand H is a non-pointing operation.

[0158] The calculation unit 134 resets the pointing operation count to 0 (step S48A). After the calculation unit 134 finishes the process of step S48A, it ends a series of processes (End).

[0159] In addition, if the calculation unit 134 determines in step S42 that the previous operation state was not a pointing operation (S42: No), it determines whether the number of detection points where the electrostatic capacitance exceeds the pointing operation threshold is equal to or less than the determination count threshold (step S43B). Step S43B is a process for determining whether a non-pointing operation has been performed.

[0160] If the calculation unit 134 determines that the number of detection points where the electrostatic capacitance exceeds the pointing operation threshold is not less than or equal to the determination number threshold (S43B: No), it resets the number of pointing operations to 0 times (step S44B). The number of pointing operations indicates the number of times that a pointing operation is tentatively determined to have been performed by determining "Yes" in step S43B. After the calculation unit 134 finishes the process of step S44B, it ends a series of processes (End).

[0161] If the calculation unit 134 determines in step S43B that the number of detection points where the electrostatic capacitance exceeds the non-pointing operation threshold is less than or equal to the determination number threshold (S43B: Yes), it increments the number of pointing operations (step S45B).

[0162] The calculation unit 134 determines whether the number of pointing operations is 3 or more (step S46B).

[0163] If the calculation unit 134 determines that the number of pointing operations is not 3 or more (S46B: No), it ends a series of processes (End).

[0164] If the calculation unit 134 determines in step S46B that the number of pointing operations is 3 or more (S46B: Yes), it changes the variable "operation state" to "pointing operation" (step S47B). If it is not determined as "Yes" three times in a row in step S43B, the number of pointing operations does not reach 3 times.

[0165] Therefore, when it is determined three times in a row in step S43B that the number of detection points where the electrostatic capacitance exceeds the pointing operation threshold is less than or equal to the determination number threshold (S43B: Yes), it is determined that the operation of the hand H is a pointing operation. In the case of sudden noise generation, etc., in order not to misjudge the operation method, when it is determined three times in a row that the number of detection points where the electrostatic capacitance exceeds the pointing operation threshold is less than or equal to the determination number threshold (S43B: Yes), it is determined that the operation of the hand H is a pointing operation.

[0166] The calculation unit 134 resets the number of non-pointing operations to 0 (step S48B). After the calculation unit 134 finishes the process of step S48B, it ends a series of processes (End).

[0167] <Distribution of electrostatic capacitance detected by the electrostatic sensor 120>

[0168] Figures 11A to 11D is a diagram showing an example of the distribution of the electrostatic capacitance detected by the electrostatic sensor 120. In Figures 11A to 11D As an example, at the point where the sensor electrodes 121X and 121Y cross in plan view, there are 18 in the X direction and 18 in the Y direction, and the electrostatic sensor 120 can detect the electrostatic capacitance at 324 detection points of 18×18. Therefore, Figures 11A to 11DShows 324 boxes arranged in 18 rows horizontally and 18 rows vertically.

[0169] In addition, the detection points of the electrostatic capacitance that are detected to exceed Figures 4A to 4C the second threshold value TH2 shown are marked with an "×", and the detection points of the electrostatic capacitance that are detected to exceed the first threshold value TH1 but are below the second threshold value TH2 are marked with a " / ". In addition, the detection points where the electrostatic capacitance is below the first threshold value TH1 are not marked with an "×" or a " / ", and are represented by a hollow shape.

[0170] In Figure 11A there are 8 "×" marks in the upper left corner, and no " / " marks. As an example, the "×" marks are the detection points where the hand H is in the contact state. Since the number is less than 12, which is the determination number threshold, the electrostatic coordinate input device 100 determines that a contact state pointing operation has been performed. In addition, the coordinates of the contact state pointing operation become the position of the detection point with the largest electrostatic capacitance among the detection points indicated by the 8 "×" marks.

[0171] In Figure 11B there are 8 "×" marks in the upper left corner, and 64 " / " marks in the lower side closer to the center. As an example, the "×" marks are the detection points where the hand H is in the contact state. Since the number exceeds 12, which is the determination number threshold, the electrostatic coordinate input device 100 determines that a contact state non-pointing operation has been performed. In addition, the coordinates of the contact state non-pointing operation become the position of the detection point with the largest electrostatic capacitance among the detection points indicated by the 72 "×" marks.

[0172] In Figure 11C there are 8 "×" marks in the upper left corner, and 37 " / " marks around the "×" marks. In Figure 11C the "×" marks are, as an example, the detection points where the hand H is in the determination state. Since the number is 90 or less than the determination number threshold, the electrostatic coordinate input device 100 determines that a determination state pointing operation has been performed. In addition, the coordinates of the determination state pointing operation become the position of the detection point with the largest electrostatic capacitance among the detection points indicated by the 8 "×" marks.

[0173] In Figure 11D there are 8 "×" marks in the upper left corner, and 100 " / " marks around the "×" marks. In Figure 11D the "×" marks are, as an example, the detection points where the hand H is in the determination state. Since the number exceeds 90, which is the determination number threshold, the electrostatic coordinate input device 100 determines that a determination state non-pointing operation has been performed. In addition, the coordinates of the determination state non-pointing operation become the position of the detection point with the largest electrostatic capacitance among the detection points indicated by the 8 "×" marks.

[0174] <Operation examples of the electrostatic coordinate input device 100>

[0175] Figures 12A to 12EThis is a diagram showing an operation example of the electrostatic coordinate input device 100. In Figures 12A to 12E the case of a pointing operation is described. In Figures 12A to 12E a simplified illustration shows Figure 1 the numeric keypad portion of the electrostatic coordinate input device 100 shown in

[0176] In Figure 12A the electrostatic coordinate input device 100 is in a standby state, the backlight is off, and the numeric keypad portion and the input content display section 115 are dimmed. In Figure 12A the distance state is a non-detection state.

[0177] In Figure 12B the hand H approaches the operation surface 105A, and the distance state is an approach state. In the approach state, the electrostatic coordinate input device 100 switches from the standby state to the activation state, and the backlight is turned on for all keys and the input content display section 115. By turning on the backlight, the numeric keypad portion and the input content display section 115 become bright.

[0178] In Figure 12C the hand H further approaches the operation surface 105A, and the distance state is a selection state. As an example, the fingertip FT is located above the 7 key, and the backlights of the 7 key and the surrounding 4, 5, 8, C, 0 keys are turned on, while the backlights of the other keys are turned off.

[0179] In Figure 12D the hand H further approaches the operation surface 105A, and the distance state is a determination state. As an example, the fingertip FT is located above the 7 key, and only the backlight of the 7 key for which the operation has been determined is turned on, while the backlights of the other keys are turned off. Thus, the user can visually recognize that the operation on the 7 key has been determined. In Figure 12D the hand H is in a state where its position relative to the operation surface 105A is maintained at the position described in Figure 12D and waiting for the operation to be determined, and the distance state is a determination state.

[0180] In Figure 12E the hand H is in a state where its position relative to the operation surface 105A is continuously maintained at the position described in Figure 12D and the operation has been determined. The fingertip FT is located above the 7 key, and by determining the operation, the number 7 is displayed on the input content display section 115.

[0181] Figures 13A to 13F This is a diagram showing an operation example of the electrostatic coordinate input device 100. In Figures 13A to 13F the following situation is described: as described in Figure 12E after the input of the number 7 has been determined, the hand H is sufficiently separated from the operation surface 105A, and then the non-pointing operation shown in Figure 4C is performed.Figure 4C The non-pointing operation shown is a non-pointing operation in which the fingertip FT is tilted relative to the operation surface 105A and the palm also approaches the operation surface 105A. In Figures 13A to 13F , it is simply shown Figure 1 a part of the numeric keys of the electrostatic coordinate input device 100 shown and the input content display section 115.

[0182] In Figure 13A , the distance state of the electrostatic coordinate input device 100 is a non-detection state. Therefore, the backlights of the numeric keys are turned off and it is darker, but for the input content display section 115, the backlight is turned on to display the input content.

[0183] In Figure 13B , the hand H of the non-pointing operation approaches the operation surface 105A, and the distance state is an approaching state. By becoming the approaching state, the electrostatic coordinate input device 100 turns on the backlights for all the keys and the input content display section 115, but since the electrostatic coordinate input device 100 detects that a non-pointing operation has been performed, a warning message "Please raise your fingertip and get closer" is displayed on the input content display section 115. This is to prompt the user to perform a pointing operation.

[0184] In Figure 13C , the hand H of the non-pointing operation further approaches the operation surface 105A, and the distance state is a selection state. As an example, the maximum electrostatic capacitance is located above the 5 key, but since it is a non-pointing operation, the backlights of the 7 key and the surrounding 4, 5, 8, C, 0 keys are turned on, and the backlights of the other keys are turned off.

[0185] In Figure 13D , the hand H further approaches the operation surface 105A, and the distance state is a determination state. As an example, the fingertip FT is located above the 5 key, and only the backlight of the 5 key is turned on, and the backlights of the other keys are turned off. In this state, the fingertip FT is also tilted, so a warning message "Please raise your fingertip" is displayed on the input content display section 115.

[0186] In Figure 13E , it represents Figure 13D the state where the state shown continues and the time required for the determination operation has passed, but since it is a non-pointing operation, the operation is not determined. In this state, the fingertip FT is also tilted, so a warning message "Please raise your fingertip" is displayed on the input content display section 115.

[0187] In Figure 13F , it shows the state where the fingertip FT is raised relative to the operation surface 105A starting from the state described in Figure 13E . The operation is determined by raising the fingertip FT, and in addition to 7, 5 is also displayed on the input content display section 115.

[0188] <Effect>

[0189] The electrostatic coordinate input device 100 includes: an operation surface 105A; a plurality of sensor electrodes 121X and 121Y arranged on the back side of the operation surface 105A; a measurement circuit (such as an AD conversion unit 132, etc.) that measures the electrostatic capacitance of each of the plurality of sensor electrodes 121X and 121Y; and a calculation unit 134 that calculates the position of the indicator based on the plurality of electrostatic capacitances measured by the measurement circuit (such as the AD conversion unit 132, etc.). The calculation unit 134 calculates the maximum electrostatic capacitance between the indicator and the sensor electrodes 121X and 121Y based on the plurality of electrostatic capacitances, sets a non-pointing determination threshold for determining a non-pointing operation that is not a pointing operation of the indicator based on the maximum electrostatic capacitance, and if the number of electrostatic capacitances exceeding the non-pointing determination threshold among the plurality of electrostatic capacitances exceeds the determination number threshold, it is determined that the operation of the indicator is a non-pointing operation.

[0190] By setting the non-pointing determination threshold based on the maximum electrostatic capacitance, it is possible to measure the cross-sectional area at a position a certain distance away from the operation surface 105A with the position closest to the operation surface 105A in the hand H as a reference. That is, if the cross-sectional area at a position a few cm away from the fingertip FT is above a specified value, it is regarded as a non-pointing operation of not pointing to the operation surface 105A. By accurately discriminating the state of not pointing to the operation surface 105A even when non-contact, misoperations can be prevented.

[0191] Therefore, it is possible to provide an electrostatic coordinate input device 100 that can accurately determine operations such as contact or approach according to the distance from the indicator with high precision and can suppress misoperations.

[0192] In addition, the calculation unit 134 sets a pointing determination threshold for determining that the operation of the indicator is a pointing operation based on the maximum electrostatic capacitance, and if the number of electrostatic capacitances exceeding the pointing determination threshold among the plurality of electrostatic capacitances is below the determination number threshold, it is determined that the operation of the indicator is a pointing operation. Therefore, it is also possible to accurately determine the pointing operation.

[0193] In addition, the calculation unit 134 determines which of the plurality of distance states the distance between the indicator and the operation surface 105A conforms to based on the maximum electrostatic capacitance. The non-pointing determination threshold, the pointing determination threshold, and the determination number threshold are determined for each of the plurality of distance states. The shorter the distance represented by the plurality of distance states, the larger the value the non-pointing determination threshold is set to. Therefore, it is possible to provide an electrostatic coordinate input device 100 that can simply set an appropriate non-pointing determination threshold, can accurately determine operations such as contact or approach according to the distance from the indicator with high precision, and can suppress misoperations.

[0194] In addition, multiple distance states include a contact state indicating that the operation surface 105A is in contact with the indicator and multiple non-contact states indicating that the operation surface 105A is not in contact with the indicator. The non-pointing determination threshold in the contact state is larger than the non-pointing determination thresholds in the multiple non-contact states, the pointing determination threshold in the contact state is larger than the pointing determination thresholds in the multiple non-contact states, and the determination count threshold in the contact state is smaller than the determination count thresholds in the multiple non-contact states. In the case of the contact state, the pointing operation and the non-pointing operation are discriminated based on the contact area. That is, it is discriminated by the area of contact with the operation surface 105A. Therefore, by making the non-pointing operation threshold and the pointing operation threshold larger than the non-pointing operation threshold and the pointing operation threshold in the non-contact state, the determination accuracy can be improved. In addition, by making the determination count threshold in the contact state smaller than the determination count thresholds in the multiple non-contact states, the determination accuracy can be improved.

[0195] In addition, the pointing determination thresholds in the multiple non-contact states are equal to each other, and the determination count thresholds in the multiple non-contact states are equal to each other. Therefore, it is particularly useful in the case of detecting a non-pointing operation and in the case of applying an operation method that requires the hand H to leave the operation surface 105A once.

[0196] In addition, the multiple non-contact states are, according to the distances represented by the multiple distance states, from short to long, a determination state for determining the input content, a selection state for selecting input candidates, an approaching state for approaching the input candidates, and a non-detection state in which the indicator is not detected. The non-pointing determination threshold in the non-detection state is the same value as the non-pointing determination threshold in the approaching state, the pointing determination threshold in the non-detection state is the same value as the pointing determination threshold in the approaching state, and the determination count threshold in the non-detection state is the same value as the determination count threshold in the approaching state. Therefore, it is possible to simultaneously perform the detection of the hand H when it is in the approaching state and the detection of the non-pointing operation.

[0197] In addition, when the operation unit 134 determines that the operation of the indicator is a pointing operation, if the state where the number of electrostatic capacitances exceeding the non-pointing determination threshold exceeds the determination number threshold holds continuously for a specified number of times, it is determined that the operation of the indicator is a non-pointing operation. Until the state where the number of electrostatic capacitances exceeding the non-pointing determination threshold exceeds the determination number threshold holds continuously for a specified number of times in the state where the operation of the indicator is determined to be a pointing operation, it is determined that the operation of the indicator is a non-pointing operation. In the state where the operation of the indicator is determined to be a non-pointing operation, if the state where the number of electrostatic capacitances exceeding the pointing determination threshold is equal to or less than the determination number threshold holds continuously for a specified number of times, it is determined that the operation of the indicator is a pointing operation. In the state where the operation of the indicator is determined to be a non-pointing operation, until the state where the number of electrostatic capacitances exceeding the pointing determination threshold is equal to or less than the determination number threshold holds continuously for a specified number of times, it is determined that the operation of the indicator is a non-pointing operation. Therefore, it is possible to effectively suppress false detection caused by noise.

[0198] In addition, it further includes a display unit (input content display unit 115). When the operation unit 134 determines that the operation of the indicator is a non-pointing operation, a message requesting a pointing operation with the indicator is displayed on the display unit (input content display unit 115). Therefore, it is possible to guide the user to correctly perform the operation by raising the fingertip FT through the pointing operation and suppress misoperations.

[0199] An operation determination method in an electrostatic coordinate input device, the electrostatic coordinate input device including: an operation surface 105A; a plurality of sensor electrodes 121X and 121Y arranged on the back side of the operation surface 105A; a measurement circuit (such as an AD conversion unit 132) for measuring the electrostatic capacitances of the plurality of sensor electrodes 121X and 121Y; and a calculation unit 134 for calculating the position of the indicator based on the plurality of electrostatic capacitances measured by the measurement circuit (such as the AD conversion unit 132). In this method, the maximum electrostatic capacitance between the indicator and the sensor electrodes 121X and 121Y is calculated based on the plurality of electrostatic capacitances, and a non-pointing determination threshold for determining a non-pointing operation that is not a pointing operation of the indicator is set based on the maximum electrostatic capacitance. When the number of electrostatic capacitances exceeding the non-pointing determination threshold among the plurality of electrostatic capacitances exceeds the determination number threshold, it is determined that the operation of the indicator is a non-pointing operation.

[0200] By setting the non-pointing determination threshold based on the maximum electrostatic capacitance, it is possible to measure the cross-sectional area at a position a certain distance away from the operation surface 105A with the position closest to the operation surface 105A in the hand H as a reference. That is, if the cross-sectional area at a position several centimeters away from the fingertip FT is equal to or more than a specified value, it is regarded as a non-pointing operation where the operation surface 105A is not pointed. By accurately discriminating the state where the operation surface 105A is not pointed even when not in contact, it is possible to prevent misoperations.

[0201] Therefore, an operation determination method in an electrostatic coordinate input device that can provide operations such as highly accurately determining the presence or absence of contact or proximity based on the distance from an indicator and can suppress misoperations is provided.

[0202] <Modification example>

[0203] Figures 14A to 14C It is a diagram showing a modification example of table data representing thresholds used in non-pointing operation determination processing.

[0204] In Figure 14A In the shown table data, the determination number thresholds in multiple non-contact states are equal to each other. The shorter the distances represented by the multiple distance states are, the larger the pointing determination thresholds in the multiple non-contact states are.

[0205] Specifically, compared with the table data shown in Figure 9 the pointing determination thresholds in the selection state and the confirmation state are larger, and are set to 70 and 190 respectively. By increasing the values of the pointing determination thresholds in the selection state and the confirmation state, it is possible to return to the non-detection state even without the hand H leaving the operation surface 105A.

[0206] In addition, in Figure 14B In the shown table data, the pointing determination thresholds in multiple non-contact states are equal to each other. The shorter the distances represented by the multiple distance states are, the smaller the determination number thresholds in the multiple non-contact states are.

[0207] Specifically, compared with the table data shown in Figure 9 the values of the determination number thresholds in the selection state and the confirmation state are smaller, and are set to 56 and 30 respectively. That is, it is set such that as the state changes from the contact state to the confirmation state, the selection state, the proximity state, and the non-detection state, the determination number threshold becomes larger. Therefore, the farther the hand H is from the operation surface 105A, the more capable it is of discriminating between the pointing operation and the non-pointing operation in a state with a large cross-sectional area.

[0208] In addition, Figure 14C In the shown table data, the shorter the distances represented by the multiple distance states are, the larger the pointing determination threshold is and the smaller the determination number threshold is. Specifically, it is a data configuration combining the table data shown in Figure 14A and Figure 14B shown.

[0209] Specifically, compared with the table data shown in Figure 9 the pointing determination thresholds in the selection state and the confirmation state are larger, and are set to 70 and 190 respectively. In addition, the values of the determination number thresholds in the selection state and the confirmation state are smaller, and are set to 56 and 30 respectively.

[0210] Therefore, by increasing the values of the pointing determination thresholds for the selection state and the determination state, it is possible to return to the non-detection state even without the hand H leaving the operation surface 105A. In addition, the farther the hand H is from the operation surface 105A, the more capable it is of discriminating between a pointing operation and a non-pointing operation in a state with a larger cross-sectional area.

[0211] Figure 15 It is a flowchart showing a modified example of the non-pointing operation determination process. Figure 15 The shown flowchart replaces the process of step S41 in the flowchart of the non-pointing operation determination process shown Figure 10 with the process of step S41M. The processes after step S42 are the same as those in the flowchart of the non-pointing operation determination process shown Figure 10 Therefore, here, the process of step S41M will be described.

[0212] The calculation unit 134 sets the non-pointing operation threshold to a value obtained by multiplying the maximum value of the electrostatic capacitance detected by the electrostatic sensor 120 in this control cycle by a coefficient of 0.8, sets the pointing operation threshold to a value obtained by multiplying the maximum value of the electrostatic capacitance detected by the electrostatic sensor 120 in this control cycle by a coefficient of 0.5, and sets the determination count threshold to a value obtained by dividing 10000 by the maximum value of the electrostatic capacitance detected by the electrostatic sensor 120 in this control cycle (step S41M).

[0213] That is, the non-pointing determination threshold is a value proportional to the maximum electrostatic capacitance. The coefficient multiplied by the maximum electrostatic capacitance is not limited to 0.8, as long as it is set to an appropriate value. In addition, the pointing determination threshold is a value proportional to the maximum electrostatic capacitance. The coefficient multiplied by the maximum electrostatic capacitance is not limited to 0.5, as long as it is smaller than the coefficient multiplied by the non-pointing operation threshold and is set to an appropriate value. That is, the pointing determination threshold is a value larger than the non-pointing determination threshold. In addition, the determination count threshold is a value inversely proportional to the maximum electrostatic capacitance. Therefore, even without using Figure 9 and Figures 14A to 14C the table data of the thresholds as shown, it is possible to determine a non-pointing operation.

[0214] As described above, the electrostatic coordinate input device and the operation determination method in the exemplary embodiment of the present disclosure have been described, but the present disclosure is not limited to the specifically disclosed embodiments, and various deformations and changes can be made without departing from the claims.

[0215] In addition, this international application claims priority based on Japanese Patent Application 2022-178084 filed on November 7, 2022, the entire content of which is incorporated herein by reference into this international application.

[0216] Explanation of Reference Numerals

[0217] 100 Electrostatic coordinate input device

[0218] 101 Housing

[0219] 105 Top plate

[0220] 105A Operating surface

[0221] 110 Display device

[0222] 111 GUI button

[0223] 115 Input content display section

[0224] 120 Electrostatic sensor

[0225] 121 X sensor electrode

[0226] 121 Y sensor electrode

[0227] 122 X wiring

[0228] 122 Y wiring

[0229] 130 Control device

[0230] 131 Main control section

[0231] 132 AD conversion section

[0232] 133 Counter

[0233] 134 Calculation section

[0234] 135 Motion control section

[0235] 136 Display control section

[0236] 137 Memory

Claims

1. An electrostatic coordinate input device, comprising: An operation surface; A plurality of sensor electrodes arranged on the back side of the operation surface; A measurement circuit for measuring the electrostatic capacitance of each of the plurality of sensor electrodes; and A calculation unit that calculates the position of an indicator based on the plurality of electrostatic capacitances measured by the measurement circuit, The calculation unit Calculates the maximum electrostatic capacitance between the indicator and the sensor electrodes based on the plurality of electrostatic capacitances, Sets a non-pointing determination threshold for determining a non-pointing operation that is not a pointing operation of the indicator based on the maximum electrostatic capacitance, When the number of electrostatic capacitances exceeding the non-pointing determination threshold among the plurality of electrostatic capacitances exceeds a determination number threshold, it is determined that the operation of the indicator is the non-pointing operation.

2. The electrostatic coordinate input device according to claim 1, Wherein, The calculation unit sets a pointing determination threshold for determining that the operation of the indicator is the pointing operation based on the maximum electrostatic capacitance, If the number of electrostatic capacitances exceeding the pointing determination threshold among the plurality of electrostatic capacitances is less than or equal to the determination number threshold, it is determined that the operation of the indicator is the pointing operation.

3. The electrostatic coordinate input device according to claim 2, Wherein, The calculation unit determines which of a plurality of distance states the distance between the indicator and the operation surface conforms to based on the maximum electrostatic capacitance, The non-pointing determination threshold, the pointing determination threshold, and the determination number threshold are determined for each of the plurality of distance states, The shorter the distance represented by the plurality of distance states, the larger the value set for the non-pointing determination threshold.

4. The electrostatic coordinate input device according to claim 3, Wherein, The plurality of distance states include a contact state indicating contact between the operation surface and the indicator and a plurality of non-contact states indicating non-contact between the operation surface and the indicator, The non-pointing determination threshold in the contact state is greater than the non-pointing determination threshold in the plurality of non-contact states, The pointing determination threshold in the contact state is greater than the pointing determination threshold in the plurality of non-contact states, The determination number threshold in the contact state is less than the determination number threshold in the plurality of non-contact states.

5. The electrostatic coordinate input device according to claim 4, Wherein, The pointing determination thresholds in the plurality of non-contact states are equal to each other, The determination number thresholds in the plurality of non-contact states are equal to each other.

6. The electrostatic coordinate input device according to claim 4, Wherein, The determination number thresholds in the plurality of non-contact states are equal to each other, The shorter the distance represented by the plurality of distance states, the larger the pointing determination threshold in the plurality of non-contact states.

7. The electrostatic coordinate input device according to claim 4, Wherein, The pointing determination thresholds in the plurality of non-contact states are equal to each other, The shorter the distance represented by the plurality of distance states, the smaller the determination number threshold in the plurality of non-contact states.

8. The electrostatic coordinate input device according to claim 4, wherein, the shorter the distance represented by the plurality of distance states, the larger the non-pointing determination threshold and the smaller the determination number threshold.

9. The electrostatic coordinate input device according to claim 4, wherein, the plurality of non-contact states are, from the shortest to the longest distance represented by the plurality of distance states, a determination state for determining input content, a selection state for selecting an input candidate, an approaching state for approaching the input candidate, and a non-detection state in which the indicator is not detected, the non-pointing determination threshold in the non-detection state and the non-pointing determination threshold in the approaching state are the same value, the pointing determination threshold in the non-detection state and the pointing determination threshold in the approaching state are the same value, the determination number threshold in the non-detection state and the determination number threshold in the approaching state are the same value.

10. The electrostatic coordinate input device according to claim 2, wherein, the non-pointing determination threshold is a value proportional to the maximum electrostatic capacitance.

11. The electrostatic coordinate input device according to claim 10, wherein, the pointing determination threshold is a value proportional to the maximum electrostatic capacitance, and the pointing determination threshold is a value larger than the non-pointing determination threshold.

12. The electrostatic coordinate input device according to claim 10, wherein, the determination number threshold is a value inversely proportional to the maximum electrostatic capacitance.

13. The electrostatic coordinate input device according to any one of claims 2 to 12, wherein, the calculation unit, in a state where it is determined that the operation of the indicator is the pointing operation, if the state where the number of electrostatic capacitances exceeding the non-pointing determination threshold exceeds the determination number threshold continuously holds for a specified number of times, it is determined that the operation of the indicator is the non-pointing operation, in a state where it is determined that the operation of the indicator is the pointing operation, until the state where the number of electrostatic capacitances exceeding the non-pointing determination threshold exceeds the determination number threshold continuously holds for a specified number of times, it is determined that the operation of the indicator is the non-pointing operation, in a state where it is determined that the operation of the indicator is the non-pointing operation, if the state where the number of electrostatic capacitances exceeding the pointing determination threshold is equal to or less than the determination number threshold continuously holds for a specified number of times, it is determined that the operation of the indicator is the pointing operation, in a state where it is determined that the operation of the indicator is the non-pointing operation, until the state where the number of electrostatic capacitances exceeding the pointing determination threshold is equal to or less than the determination number threshold continuously holds for a specified number of times, it is determined that the operation of the indicator is the non-pointing operation.

14. The electrostatic coordinate input device according to claim 13, wherein, the electrostatic coordinate input device further includes a display unit, and the calculation unit, in a state where it is determined that the operation of the indicator is the non-pointing operation, displays a message requesting the pointing operation using the indicator on the display unit.

15. A method for operation determination in an electrostatic coordinate input device, the electrostatic coordinate input device comprising: an operation surface; a plurality of sensor electrodes arranged on the back side of the operation surface; a measurement circuit for measuring the electrostatic capacitance of each of the plurality of sensor electrodes; and a calculation unit for calculating the position of an indicator based on the plurality of electrostatic capacitances measured by the measurement circuit, wherein, the method for operation determination in the electrostatic coordinate input device, calculates the maximum electrostatic capacitance between the indicator and the sensor electrodes based on the plurality of electrostatic capacitances, sets a non-pointing determination threshold for non-pointing operations for determining non-pointing operations that are not the pointing operations of the indicator based on the maximum electrostatic capacitance, when the number of electrostatic capacitances exceeding the non-pointing determination threshold among the plurality of electrostatic capacitances exceeds a determination number threshold, determines that the operation of the indicator is the non-pointing operation.

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