Capacitive non-contact input device

Abstract

Provided is a capacitive non-contact input device capable of smoothly moving a position calculated for displaying a pointer in accordance with the position of an indicator.　The capacitive non-contact input device according to an embodiment of the present disclosure includes: a plurality of sensor electrodes disposed along a plane on a back surface side of an operation surface; a measurement circuit for measuring capacitance between each of the plurality of sensor electrodes and an indicator; and a control unit. The control unit: calculates a measurement position, which is a planar position of the indicator, and a variation in the measurement position, on the basis of the capacitance measured by the measurement circuit; calculates a moving average position, which is a planar position of the indicator, on the basis of the moving average of the measurement position at a plurality of points in time; and when calculating the moving average position, increases a weighting coefficient of the latest measurement position in the moving average as the variation decreases.

Description

Capacitive non-contact input device

[0001] The present disclosure relates to a capacitive non-touch input device.

[0002] 2. Description of the Related Art Conventionally, there has been available electronic equipment that includes a planar display unit and a touch panel that is overlaid on the display unit and is capable of detecting two-dimensional coordinates along the surface of the display unit and the vertical distance to a pointer, and that is capable of outputting a pointer to the two-dimensional coordinates of the display unit within a predetermined range where the vertical distance is greater than 0. In a pointer mode in which a predetermined function is performed in accordance with the position of the pointer, the touch panel divides an area for the two-dimensional coordinates into a number of divisions that increases as the vertical distance decreases, and when the two-dimensional coordinates of the pointer correspond to one of the divided areas, the touch panel performs a rounding process to two-dimensional coordinates that have a fixed relationship and correspond to the one area, and outputs a pointer to the rounded two-dimensional coordinates on the display unit, and suppresses wobble of the pointer within the predetermined range where the vertical distance is greater than 0 (for example, see Patent Document 1).

[0003] JP 2014-164619 A

[0004] However, in conventional electronic devices, the number of divisions into areas for the two-dimensional coordinates of the touch panel decreases as the vertical distance between the two-dimensional coordinates and the pointer increases, which can cause the pointer movement to lose continuity or become discrete when crossing areas due to a long vertical distance. In other words, conventional electronic devices have a problem in that the movement of the position calculated for displaying the pointer according to the position of the pointer is not smooth.

[0005] Therefore, an object of the present invention is to provide a capacitive non-contact input device that can smoothly move the position calculated for displaying a pointer in accordance with the position of a pointer.

[0006] A capacitive non-touch input device according to an embodiment of the present disclosure includes a plurality of sensor electrodes arranged along a plane on the rear side of an operating surface, a measurement circuit that measures the capacitance between each of the plurality of sensor electrodes and an indicator, and a control unit. The control unit calculates a measurement position, which is the planar position of the indicator, and a variance in the planar position of the indicator based on the capacitance measured by the measurement circuit, and calculates a moving average position, which is the planar position of the indicator, based on a moving average of the measurement positions at a plurality of points in time. When calculating the moving average position, the smaller the variance, the larger the weighting coefficient of the most recent measurement position in the moving average.

[0007] It is possible to provide a capacitive non-contact input device that can smoothly move the position calculated for displaying the pointer in accordance with the position of the indicator.

[0008] 1 is a diagram illustrating an example of a configuration of a capacitance type non-contact input device according to an embodiment; FIG. 2 is a diagram illustrating an example of a threshold value for determining an operation method in the capacitance type non-contact input device according to an embodiment in relation to an operation surface; FIG. 3 is a diagram illustrating an example of a configuration of a capacitance type sensor, a control device, etc. of the capacitance type non-contact input device according to an embodiment; FIG. 4 is a flowchart illustrating an example of a process (part 1) executed by a control unit of the capacitance type non-contact input device according to an embodiment; FIG. 5 is a flowchart illustrating an example of a modified example (part 2) of a process executed by a control unit of the capacitance type non-contact input device according to an embodiment; FIG. 6 is a flowchart illustrating an example of another modified example (part 3) of a process executed by a control unit of the capacitance type non-contact input device according to an embodiment; FIG. 7 is a flowchart illustrating an example of a further modified example (part 4) of a process executed by a control unit of the capacitance type non-contact input device according to an embodiment; FIG. 8 is a diagram illustrating an example of a simulation result of the capacitance type non-contact input device according to an embodiment; FIG. 9 is a diagram illustrating an example of a simulation result of the capacitance type non-contact input device according to an embodiment; Fig. 10 is a flowchart showing an example of a subroutine process of a variation calculation process. Fig. 11 is a flowchart showing an example of a subroutine process of a variation calculation process. Fig. 12 is a flowchart showing an example of a subroutine process of a variation calculation process. Fig. 13 is a flowchart showing an example of a subroutine process of a moving average position calculation process. Fig. 14 is a flowchart showing an example of a subroutine process of a moving average position calculation process. Fig. 15 is a diagram showing processing of a modified example of array movement of measurement positions (part 2).

[0009] Hereinafter, an embodiment to which the capacitive non-contact input device of the present disclosure is applied will be described.

[0010] 1A is a diagram showing an example of the configuration of a capacitive non-contact input device 100 according to an embodiment. Fig. 1A shows a state in which an input image is displayed on a display 110. Fig. 1B is a diagram showing an example of a threshold value for determining an operation method in the capacitive non-contact input device 100 in relation to an operation surface.

[0011] FIG. 2 is a diagram showing an example of the configuration of the capacitance sensor 120, the control device 130, and the like of the capacitance type non-contact input device 100. As shown in FIG.

[0012] In the following description, an XYZ coordinate system is defined. The X axis is the first axis, the Y axis is the second axis, and the Z axis is the third axis. 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 perpendicular to each other. In the following description, the -Z direction is the direction approaching the capacitance sensor 120, and the +Z direction is the direction away from the capacitance sensor 120. In addition, a planar view refers to a view from the XY plane. In the following description, the length, width, thickness, etc. of each part may be exaggerated to make the configuration easier to understand.

[0013] The capacitive non-contact input device 100 may be, for example, a tablet-type input device that is placed in a store or facility and used by an unspecified number of users, or an input unit of an ATM (Automatic Teller Machine), or may be an input unit of a cooking appliance that needs to be kept clean.

[0014] <Overall Configuration of Capacitive Non-Touch Input Device 100> The capacitive non-contact input device 100 includes a housing 101, a top panel 105, a display 110, a capacitive sensor 120, an input sensor circuit 125A, an image display circuit 125B, and a control device 130. The input sensor circuit 125A measures the capacitance between the capacitive sensor 120 and a fingertip FT. The fingertip FT is an example of a pointer.

[0015] 1A omits the control device 130 (see FIG. 2 ), but as an example, the control device 130 is provided inside the housing 101 below the display 110 and the capacitance sensor 120. The capacitance-type contactless input device 100 includes the capacitance sensor 120 and the control device 130 shown in FIG.

[0016] <Housing 101 and Top Panel 105> The housing 101 is a case made of resin, metal, or the like that houses the display 110, the capacitance sensor 120, and the control device 130. The display 110 is disposed below the transparent capacitance sensor 120 and is visible through an operation surface 105A, which is the upper surface of a transparent top panel 105 provided in an opening at the top of the housing 101. The capacitance sensor 120 may be retrofitted to an existing display 110. The display and the control device 130 may be integrated as in a tablet computer. The display and the control device 130 may be separate as in a desktop computer.

[0017] <Four regions of the capacitive non-contact input device 100 and operation methods> The capacitive non-contact input device 100 can be operated in both a state where an indicator such as a user's hand is not in contact with the operation surface 105A, and a state where an indicator such as a user's hand is in contact with the operation surface 105A.

[0018] The capacitive non-contact input device 100 is an input device that is operated by a user performing a pointing operation. The pointing operation is 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 it is preferable to use one finger.

[0019] When performing such a pointing operation, if the finger is not approximately perpendicular to the operation surface 105A, the entire palm approaches the operation surface 105A, making it difficult to measure the position of the fingertip FT.

[0020] Unless otherwise specified, the following describes a case where a user performs a pointing operation with a fingertip FT as a pointer. In addition, hereinafter, performing an operation (proximity operation, selection operation, decision operation, or touch operation) with the fingertip FT will be simply expressed as an operation (proximity operation, selection operation, decision operation, or touch operation) with the fingertip FT.

[0021] There are three types of non-contact operation methods for the capacitive non-contact input device 100: a proximity operation, a selection operation, and a decision operation.

[0022] In order to distinguish between the four operation methods, the capacitive non-contact input device 100 divides the area where the fingertip FT is located into four areas depending on the distance in the Z direction from the operation surface 105A. The four areas are divided by a proximity capacitance threshold TH1, a selection capacitance threshold TH2, a final capacitance threshold TH3, and a contact capacitance threshold TH4, which represent capacitance values ​​depending on the distance from the operation surface 105A. The four areas are, in order from the operation surface 105A side, a decision area from the final capacitance threshold TH3 to the contact capacitance threshold TH4, a selection area from the selection capacitance threshold TH2 to the final capacitance threshold TH3, a proximity area from the proximity capacitance threshold TH1 to the selection capacitance threshold TH2, and a standby area farther than the proximity capacitance threshold TH1.

[0023] Since the distance between the operation surface 105A and the surface of the capacitance sensor 120 (the surface on the +Z direction side) is constant (fixed distance), determining one of the four operation methods according to the distance in the Z direction from the operation surface 105A is equivalent to determining one of the four operation methods according to the distance in the Z direction from the surface of the capacitance sensor 120.

[0024] <Decision Area, Selection Area, Proximity Area, and Wait Area> The decision area is an area in which the input mode is set to decision mode by the control unit 131. When it is determined that the fingertip FT is located within the decision area, a decision operation is performed.

[0025] The selection area is an area in which the control unit 131 sets the input mode to a selection mode. When the control unit 131 determines that the fingertip FT is located within the selection area, a selection operation is performed.

[0026] The proximity area is an area in which the control unit 131 sets the input mode to the proximity mode. When the input assistance application determines that the fingertip FT is located within the proximity area, a proximity operation is performed. The proximity area is the area farthest from the operation surface 105A among areas in which the XY coordinates of the target object can be calculated.

[0027] The standby area is an area in which the control unit 131 sets the input mode to the standby mode. In the standby mode, the control unit 131 may turn off the power supply to the display.

[0028] <Proximity operation, selection operation, decision operation, and contact operation> A proximity operation is an operation of bringing the fingertip FT close to the operation surface 105A of the capacitive non-contact input device 100 without touching the operation surface 105A, and is an operation for switching the display of the display 110 from the standby mode display to the proximity mode display.

[0029] A selection operation is an operation in which, after performing a proximity operation, the fingertip FT is brought even closer to the operation surface 105A of the capacitive non-contact input device 100 without touching it, and a GUI button displayed on the display 110 is selected.

[0030] A confirmation operation is an operation in which, after a selection operation, the fingertip FT is brought closer to the operation surface 105A of the capacitive non-contact input device 100 without touching it, thereby issuing a click event. When a click event is issued on a GUI button, the control unit 131 confirms the operation input. The confirmation operation is a non-contact operation input, in which the fingertip FT operates the capacitive non-contact input device 100 without touching the operation surface 105A. Operation inputs performed by non-contact selection operations and confirmation operations may be referred to as hover inputs or touchless inputs. Note that even when the fingertip FT touches the operation surface 105A of the capacitive non-contact input device 100, this may be treated as confirmation mode. Alternatively, when the fingertip FT touches the operation surface 105A of the capacitive non-contact input device 100, the input may be confirmed immediately. Alternatively, when the fingertip FT touches the operation surface 105A of the capacitive non-contact input device 100, a warning screen may be displayed.

[0031] The contact operation is an operation in which, after a selection operation has been performed, the fingertip FT is brought closer to the operation surface 105A to touch the operation surface 105A, thereby confirming the operation input for the selected GUI button. The contact operation may also be referred to as a touch input.

[0032] <Display 110> The display 110 is a liquid crystal display, an organic EL (Electroluminescence) display, or the like. The display 110 is a display for realizing a GUI (Graphical User Interface). The image 115 of the application software includes an image of a GUI button 110A. The GUI button 110A is an operation unit, and is shaped, for example, to resemble a push button. The application software is designed to be operated with a two-dimensional position input device such as a mouse.

[0033] FIG. 1A shows an example of the screen of a restaurant ordering terminal. The ordering screen shows a total of 18 GUI buttons 110A, including eight GUI buttons 110A for menu items, nine GUI buttons 110A in the form of a numeric keypad, and a GUI button 110A for a clear operation. The 18 GUI buttons 110A are arranged in four rows in the Y direction and five rows in the X direction. The GUI button 110A for the clear operation has a width in the X direction equivalent to three of the nine numeric GUI buttons 110A. The rows extend in the X direction, and the Y direction extends in the column direction. Note that the GUI buttons 110A are not limited to the screen of a restaurant ordering terminal, and may be any other application as long as it is an operation screen for a touch panel.

[0034] <Capacitive Sensor 120, Input Sensor Circuit 125A, and Image Display Circuit 125B> The capacitive sensor 120 is disposed on top of the display 110, and as shown in FIG. 2 , has a plurality of sensor electrodes 121X extending in the X direction and a plurality of sensor electrodes 121Y extending in the Y direction. An input sensor circuit 125A is also integrally provided with the capacitive sensor 120. An image display circuit 125B is also integrally provided with the display 110. The input sensor circuit 125A is connected between the wiring 122X, 122Y and the control device 130. The image display circuit 125B is connected between the display 110 and the control device 130.

[0035] The sensor electrodes 121X and 121Y are connected to the control device 130 via wiring 122X and 122Y and an input sensor circuit 125A. Such a capacitance-type sensor 120 can be formed by forming a transparent conductive film such as ITO (Indium Tin Oxide) on the surface of transparent glass and patterning it into the sensor electrodes 121X and 121Y and wiring 122X and 122Y. The capacitance detected by the capacitance-type sensor 120 is input to the control device 130.

[0036] 2 shows a plurality of sensor electrodes 121X and a plurality of sensor electrodes 121Y. Note that it is preferable that the distance between the sensor electrodes 121X and the distance between the sensor electrodes 121Y are narrower than the distance between the GUI buttons 110A. In other words, it is preferable to use capacitance sensors 120 that correspond to the distance between the GUI buttons 110A.

[0037] The input sensor circuit 125A is mounted on a wiring board. The input sensor circuit 125A is provided between the wirings 122X and 122Y and the control device 130, and performs analog-to-digital (AD) conversion of the capacitance of the capacitance-type sensor 120 acquired by sequentially selecting the plurality of wirings 122X and the plurality of wirings 122Y. The input sensor circuit 125A calculates a difference value ΔAD at the intersection of each of the wirings 122X and 122Y by subtracting a reference value from the capacitance value of each of the wirings 122X and 122Y.

[0038] The difference value ΔAD is a count value of the change in the output of the input sensor circuit 125A relative to a reference value. The reference value is a value proportional to the capacitance of the sensor electrode 121 when there is no object such as a fingertip FT around the sensor electrode 121. The input sensor circuit 125A calculates the difference value ΔAD by subtracting the reference value from the measured value of the capacitance of each sensor electrode 121.

[0039] The capacitance measured by the input sensor circuit 125A is the maximum value of the capacitances between each of the plurality of sensor electrodes 121X, 121Y and the fingertip FT.

[0040] The image display circuit 125B is provided between the display 110 and the control device 130, and displays an image on the display 110 in accordance with image data sent from the control device 130.

[0041] <Control device 130> The control device 130 has a control unit 131 and a memory 132. The control device 130 is realized by a computer including a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), an input / output interface, an internal bus, etc. The control unit 131 represents the functions of the program executed by the control device 130 as functional blocks. The memory 132 functionally represents the memory of the control device 130.

[0042] The control unit 131 controls the operation of the capacitive non-contact input device 100. The control unit 131 receives the difference value ΔAD from the input sensor circuit 125A and calculates the XY coordinates (Xf, Yf) of the measurement position of the fingertip FT and the Z coordinate of the fingertip FT. The Z coordinate of the fingertip FT calculated by the control unit 131 represents the distance d between the fingertip FT and the multiple sensor electrodes 121X and 121Y. In the following description, the XY coordinates (Xf, Yf) of the measurement position of the fingertip FT may be referred to as the measurement position (Xf, Yf) or simply as the measurement position.

[0043] The Z coordinate (distance d) is calculated based on the maximum value of the difference values ​​ΔAD between each of the multiple sensor electrodes 121X, 121Y and the fingertip FT among the difference values ​​ΔAD measured by the input sensor circuit 125A. However, with this method, if the spacing between the sensor electrodes 121X, 121Y is wide, it is not possible to accurately calculate the Z coordinate (distance d) of the fingertip FT that is not directly above either of the sensor electrodes 121X, 121Y (i.e., directly above the space between any two pairs of sensor electrodes 121X, 121Y). For this reason, the Z coordinate (distance d) may be calculated using multiple ΔADs including the maximum value. For example, the XY coordinates and Z coordinate (distance d) of the fingertip FT may be calculated using the method described in Japanese Patent Application Laid-Open No. 2023-032324 (US 11,687,195 B2, CN 115904120 A, TW 202319897 A, KR 2023-0031138). In this case, the endpoint on the sensor surface of the shortest line segment, which is perpendicular to the sensor surface including the surfaces of the multiple sensor electrodes 121X and 121Y and has one endpoint at the position of the sensor surface and the other endpoint at the position where the fingertip FT is in contact with the sensor surface, is regarded as the measurement position (Xf, Yf), and the length of the shortest line segment is regarded as the distance d. In other words, the Z coordinate (distance d) may be calculated based on the maximum value of the difference value ΔAD, or may be calculated based on multiple difference values ​​ΔAD including the maximum value of the difference value ΔAD. Alternatively, the Z coordinate may be calculated as a capacitance value measured when a virtual sensor electrode of a predetermined size is located directly below the fingertip FT.

[0044] Furthermore, the control unit 131 calculates the XY coordinates (Xp, Yp) of the weighted moving average position of the fingertip FT using the measurement position (Xf, Yf) by exponential moving average (EMA). Here, a form using an exponential moving average, which is an example of a weighted moving average, will be described, but the weighted moving average is not limited to the exponential moving average, and for example, a Hull moving average may be used.

[0045] In the following description, the XY coordinates (Xp, Yp) of the weighted moving average position of the fingertip FT may be referred to as the weighted moving average position (Xp, Yp) or simply as the weighted moving average position.

[0046] The weighted moving average position (Xp, Yp) of the fingertip FT calculated by the control unit 131 is the position at which the pointer is displayed on the display 110. In other words, the weighted moving average position (Xp, Yp) of the fingertip FT calculated by the control unit 131 is the XY coordinates for displaying the pointer. By displaying the pointer at the weighted moving average position (Xp, Yp) of the fingertip FT calculated by the control unit 131, the fingertip FT and the pointer overlap when the display 110 is viewed in plan during operation. Note that the pointer may be displayed shifted from the weighted moving average position (Xp, Yp) of the fingertip FT calculated by the control unit 131. For example, the pointer may be made easier to see by shifting the position of the pointer forward (toward the operator) from the position of the fingertip FT.

[0047] The control unit 131 also controls the display of an image on the display 110 via the image display circuit 125B. The control unit 131 displays a pointer at the calculated weighted moving average position (Xp, Yp) of the fingertip FT. The control unit 131 determines whether a proximity operation, a selection operation, a decision operation, or a contact operation is being performed based on the calculated weighted moving average position (Xp, Yp) of the fingertip FT and the calculated distance d of the fingertip FT in the Z direction, and executes an operation according to the operation content.

[0048] The control unit 131 outputs a command corresponding to the operation content determined by the determination operation of the fingertip FT. For example, if the capacitive non-contact input device 100 is an ordering terminal of a restaurant, the control unit 131 transmits the name and quantity of the dish ordered by the customer to an order management terminal in the kitchen.

[0049] <Processing of Control Unit 131 (Part 1)> FIG. 3A is a flowchart showing an example of processing (Part 1) executed by the control unit 131.

[0050] The control unit 131 acquires a difference value ΔAD from the input sensor circuit 125A as the capacitance at each intersection of the capacitance type sensor 120 (step S1A). The difference value ΔAD is a measurement value of the capacitance between the capacitance type sensor 120 and the fingertip FT.

[0051] The control unit 131 calculates the measurement position (Xf, Yf) of the fingertip FT based on the difference value ΔAD (step S1B). The measurement position (Xf, Yf) is an XY coordinate calculated based on the difference value ΔAD, and therefore may be deviated from the actual position of the fingertip FT due to the influence of noise, etc.

[0052] The control unit 131 sets the initial value of the X coordinate Xp of the weighted moving average position (Xp, Yp) of the fingertip FT to the X coordinate Xf of the measurement position (Xf, Yf) (step S1C). That is, Xp=Xf.

[0053] The control unit 131 sets the initial value of the Y coordinate Yp of the weighted moving average position (Xp, Yp) of the fingertip FT to the Y coordinate Yf of the measurement position (Xf, Yf) (step S1D). That is, Yp=Yf.

[0054] The control unit 131 acquires a difference value ΔAD from the input sensor circuit 125A as the capacitance at each intersection of the capacitance type sensor 120 (step S2). The difference value ΔAD is a measurement value of the capacitance between the capacitance type sensor 120 and the fingertip FT.

[0055] The control unit 131 calculates the measurement position (Xf, Yf) of the fingertip FT based on the difference value ΔAD (step S3). The measurement position (Xf, Yf) is an XY coordinate calculated based on the difference value ΔAD, just like the measurement position (Xf, Yf) calculated in step S1B, and therefore may deviate from the actual position of the fingertip FT due to the influence of noise, etc.

[0056] The control unit 131 calculates the distance d between the operation surface 105A and the fingertip FT based on the difference value ΔAD (step S4A). As an example, the control unit 131 calculates the distance d by multiplying the reciprocal of the difference value ΔAD by a constant. Alternatively, the control unit 131 may calculate the distance d based on the difference value ΔAD by referring to table data in which the difference value ΔAD and the distance d are registered in association with each other.

[0057] The control unit 131 determines whether the distance d is longer than a predetermined distance dm (step S5A). The predetermined distance dm is the upper limit of the distance d, the meaning of which will be described later.

[0058] If the control unit 131 determines that the distance d is not longer than the predetermined distance dm (S5A: No), it calculates the X coordinate Xp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (1) (step S6A).

[0059]

[0060] Equation (1) is a formula for calculating the X-coordinate Xp of the latest weighted moving average position based on the exponential moving average of the X-coordinate Xf of the measurement position and the X-coordinate Xp of the weighted moving average position calculated in the previous control cycle. The exponential moving average is an example of a weighted moving average. In equation (1), k is a predetermined coefficient, and the weight in the exponential moving average is d×k. The smoothing coefficient in equation (1) is (1−d×k). The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A. However, the coefficient k is set within a range such that the weight d×k (where 0<d≦dm) is always greater than 0 and less than 1. In equation (1), the weighted moving average position calculated in the previous control cycle is used to reduce the amount of calculation. However, the weighted moving average position can be calculated without using the weighted moving average position calculated in the previous control cycle.

[0061] The control unit 131 calculates the Y coordinate Yp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (2) (step S7A).

[0062]

[0063] Equation (2) is an equation for calculating the Y coordinate Yp of the latest weighted moving average position based on the exponential moving average of the Y coordinate Yf of the measurement position and the Y coordinate Yp of the weighted moving average position calculated in the previous control cycle. The exponential moving average is an example of a weighted moving average. In equation (2), k is a predetermined coefficient, and the weight in the exponential moving average is d×k. The smoothing coefficient in equation (2) is (1−d×k). The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A, and may be the same as or different from the predetermined coefficient k in equation (1). However, the coefficient k is determined so that the weight d×k (where 0<d≦dm) is always greater than 0 and less than 1. Note that the weighted moving average position can be calculated without using the weighted moving average position calculated in the previous control cycle.

[0064] The control unit 131 uses the weighted moving average position (Xp, Yp) to display a pointer on the display 110 (step S10). The weighted moving average position (Xp, Yp) is an XY coordinate for displaying the pointer, and the control unit 131 displays the pointer at the weighted moving average position on the display 110.

[0065] When the control unit 131 finishes the process of step S10, the control unit 131 returns the flow to step S2 and repeats the processes of steps S2 to S10.

[0066] Furthermore, if the control unit 131 determines in step S5A that the distance d is longer than the predetermined distance dm (S5A: Yes), it calculates the X coordinate Xp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (3) (step S8A).

[0067]

[0068] Equation (3) is an equation in which the distance d in equation (1) is replaced with a predetermined distance dm. In equation (3), k is a predetermined coefficient, and the weight in the exponential moving average is dm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (1).

[0069] If the distance d is longer than the predetermined distance dm, when the weighted moving average position is calculated using the weight d×k in equation (1), the weight of the most recent measured position becomes too small in the calculation of the weighted moving average position, resulting in little change in the weighted moving average position. In other words, the pointer speed becomes too slow. To avoid this, the predetermined distance dm, which is the upper limit of the distance d, is set.

[0070] The control unit 131 calculates the Y coordinate Yp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (4) (step S9A).

[0071]

[0072] Equation (4) is an equation in which the distance d in equation (2) is replaced with a predetermined distance dm. In equation (4), k is a predetermined coefficient, and the weight in the exponential moving average is dm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (2).

[0073] After completing the process of step S9A, the control unit 131 advances the flow to step S10.

[0074] According to the processing (part 1) of the control unit 131, a weighted moving average position (Xp, Yp), which is the planar position of the fingertip FT, is calculated based on the exponential moving average of the measurement position (Xf, Yf) according to the distance d. When calculating the weighted moving average position (Xp, Yp), in equations (1) and (2), the weight (smoothing coefficient) of the latest measurement position (Xf, Yf) in the exponential moving average is increased as the distance d becomes shorter.

[0075] Specifically, when calculating the latest weighted moving average position (Xp, Yp), the weight of the weighted moving average position (Xp, Yp) in the previous control cycle is set to d×k, and the weight (smoothing coefficient) of the latest measured position (Xf, Yf) is set to (1−d×k).The shorter the distance d, the greater the weight of the latest measured position (Xf, Yf) in the exponential moving average.

[0076] Therefore, when the fingertip FT is close to the operation surface 105A, the proportion of the most recent measured position (Xf, Yf) based on the difference value ΔAD is high, allowing the pointer position to quickly track the position of the fingertip FT. Furthermore, when the fingertip FT is far from the operation surface 105A, the proportion of the weighted moving average position (Xp, Yp) calculated using the exponential moving average in the previous control cycle is high, making it possible to suppress pointer wobble. Furthermore, when the distance d is longer than the predetermined distance dm, the weight is a fixed value of dm × k regardless of the distance d, so the speed at which the pointer position tracks the position of the fingertip FT does not become extremely slow. Furthermore, by setting the fixed value (dm × k) to an appropriate value, it is possible to suppress pointer wobble.

[0077] Therefore, according to the processing (part 1) of the control unit 131, it is possible to smoothly move the weighted moving average position calculated for displaying the pointer according to the position of the fingertip FT.

[0078] Although the above describes a form in which X and Y coordinates are calculated as the weighted moving average position, it is also possible to calculate a weighted moving average position Pp on one axis. If the measurement position on one axis is Pf and the weighted moving average position is Pp, the weighted moving average position Pp can be calculated according to the following equation (5).

[0079]

[0080] <Modification (Part 2) of the Process of the Control Unit 131> Figure 3B is a flowchart showing an example of a modification (Part 2) of the process executed by the control unit 131. In Figure 3B, the same steps as those in Part 1 shown in Figure 3A are assigned the same step numbers. Steps S1A to S1D and S2 to S3 in Part 2 are the same as those in Part 1. For this reason, the description will begin with step S4B.

[0081] The control unit 131 calculates the capacitance C between the capacitance type sensor 120 and the fingertip FT based on the difference value ΔAD (step S4B). For example, the control unit 131 may calculate the capacitance C based on the difference value ΔAD by referring to table data that associates the difference value ΔAD with the capacitance C. Alternatively, the difference value ΔAD may be used as the capacitance C.

[0082] The control unit 131 determines whether the capacitance C is smaller than a predetermined capacitance Cm (step S5B). The predetermined capacitance Cm is the upper limit of the capacitance C, the meaning of which will be described later.

[0083] If the control unit 131 determines that the capacitance C is not smaller than the predetermined capacitance Cm (S5B: No), it calculates the X coordinate Xp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (6) (step S6B).

[0084]

[0085] Equation (6) is an equation for calculating the X-coordinate Xp of the weighted moving average position based on the exponential moving average of the X-coordinate Xf of the latest measurement position and the X-coordinate Xp of the weighted moving average position calculated in the previous control cycle. In equation (6), k is a predetermined coefficient, and the weight in the exponential moving average is C×k. The smoothing coefficient in equation (6) is C×k. The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A.

[0086] The control unit 131 calculates the Y coordinate Yp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (7) (step S7B).

[0087]

[0088] Equation (7) is an equation for calculating the Y coordinate Yp of the weighted moving average position based on the exponential moving average of the Y coordinate Yf of the most recent measurement position and the Y coordinate Yp of the weighted moving average position calculated in the previous control cycle. In equation (7), k is a predetermined coefficient, and the weight in the exponential moving average is C×k. The smoothing coefficient in equation (7) is C×k. The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A, and may be the same as or different from the predetermined coefficient k in equation (6).

[0089] When the control unit 131 finishes the process of step S7B, the control unit 131 advances the flow to step S10, and displays a pointer on the display 110 using the weighted moving average position (Xp, Yp) (step S10).

[0090] When the control unit 131 finishes the process of step S10, the control unit 131 returns the flow to step S2 and repeats the processes of steps S2 to S10.

[0091] Furthermore, if the control unit 131 determines in step S5B that the capacitance C is smaller than the predetermined capacitance Cm (S5A: Yes), it calculates the X-coordinate Xp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (8) (step S8B).

[0092]

[0093] Equation (8) is an equation in which the capacity C in equation (6) is replaced with a predetermined capacity Cm. In equation (8), k is a predetermined coefficient, and the weight in the exponential moving average is Cm×k. The smoothing coefficient in equation (8) is C×k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (6).

[0094] If the capacitance C is smaller than the predetermined capacitance Cm, when the weighted moving average position is calculated using the weight C×k in equation (6), the weight of the most recent measured position becomes too small in the calculation of the weighted moving average position, resulting in little change in the weighted moving average position. In other words, the pointer speed becomes slow. To avoid this, a predetermined capacitance Cm is set as the lower limit of the capacitance C.

[0095] The control unit 131 calculates the Y coordinate Yp of the weighted moving average position (Xp, Yp) of the fingertip FT according to equation (9) (step S9B).

[0096]

[0097] Equation (9) is an equation obtained by replacing the capacitance C in equation (7) with a predetermined capacitance Cm. In equation (9), k is a predetermined coefficient, and the weight in the exponential moving average is Cm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (7).

[0098] After completing the process of step S9A, the control unit 131 advances the flow to step S10.

[0099] According to the processing (part 2) of the control unit 131, a weighted moving average position (Xp, Yp), which is the planar position of the fingertip FT, is calculated based on the exponential moving average of the measurement position (Xf, Yf) according to the capacitance C. When calculating the weighted moving average position (Xp, Yp), in equations (6) and (7), the larger the capacitance C, the greater the weight of the most recent measurement position (Xf, Yf) in the exponential moving average.

[0100] Specifically, when calculating the weighted moving average position (Xp, Yp), the weight of the weighted moving average position (Xp, Yp) in the previous control cycle is set to (1-C×k), and the weight of the most recent measured position (Xf, Yf) is set to C×k. The larger the capacitance C, the greater the weight of the most recent measured position (Xf, Yf) in the exponential moving average.

[0101] Therefore, when the fingertip FT is close to the operation surface 105A, the proportion of the most recent measured position (Xf, Yf) based on the difference value ΔAD is high, allowing the pointer position to track the position of the fingertip FT. Furthermore, when the fingertip FT is away from the operation surface 105A, the proportion of the weighted moving average position (Xp, Yp) calculated using the exponential moving average in the previous control cycle is high, making it possible to suppress pointer wobble. Furthermore, when the capacitance C is less than the predetermined capacitance Cm, the weight is a fixed value of Cm×k regardless of the capacitance C, so the speed at which the pointer position tracks the position of the fingertip FT does not become extremely slow. Furthermore, by setting the fixed value (Cm×k) to an appropriate value, it is possible to suppress pointer wobble.

[0102] Therefore, according to the processing (part 2) of the control unit 131, it is possible to smoothly move the weighted moving average position calculated for displaying the pointer according to the position of the fingertip FT.

[0103] Although the above describes a form in which X and Y coordinates are calculated as the weighted moving average position, it is also possible to calculate a weighted moving average position Pp on one axis. If the most recent measured position on one axis is Pf and the weighted moving average position is Pp, the weighted moving average position Pp can be calculated according to the following equation (10).

[0104]

[0105] <Another Modified Example (Part 3) of the Processing of the Control Unit 131> Figure 3C is a flowchart showing an example of another modified example (Part 3) of the processing executed by the control unit 131. In Figure 3C, the same steps as those in Part 1 shown in Figure 3A are assigned the same step numbers. Steps S1A to S1D and S2 to S5A in Part 3 are the same as those in Part 1. For this reason, the description will begin with step S1E.

[0106] After completing step S1D, control unit 131 acquires difference values ​​ΔAD from input sensor circuit 125A as the capacitance at each intersection of capacitance sensor 120 (step S1E). Step S1E is the second acquisition of difference values ​​ΔAD. The difference values ​​ΔAD are the measured values ​​of the capacitance between capacitance sensor 120 and fingertip FT.

[0107] The control unit 131 calculates the measurement position (Xf, Yf) of the fingertip FT based on the difference value ΔAD acquired in step S1E (step S1F). The measurement position (Xf, Yf) calculated in step S1F is an XY coordinate calculated based on the difference value ΔAD acquired in step S1E. The measurement position (Xf, Yf) may be shifted from the actual position of the fingertip FT due to the influence of noise, etc.

[0108] The control unit 131 calculates an initial value of velocity Xv, which is the velocity of the fingertip FT in the X direction (step S1G). The initial value of velocity Xv is the value obtained by subtracting Xp, which was set as the X coordinate of the measurement position measured the first time in step S1C, from Xf, the X coordinate of the measurement position measured the second time, calculated in step S1F. In other words, Xv = Xf - Xp. By keeping the measurement time interval constant, the calculation of dividing distance by time is omitted.

[0109] The control unit 131 calculates an initial value of the velocity Yv, which is the velocity of the fingertip FT in the Y direction (step S1H). The initial value of the velocity Yv is a value obtained by subtracting Yp, which was set as the Y coordinate of the measurement position measured initially in step S1D, from Yf, the Y coordinate of the measurement position measured the second time and calculated in step S1F. In other words, Yv = Yf - Yp. By keeping the measurement time interval constant, the calculation of dividing the distance by time is omitted.

[0110] The control unit 131 sets the X coordinate Xf of the measurement position measured for the second time in step S1F as the initial value of the X coordinate Xp of the weighted moving average position (step S1I), i.e., Xp=Xf.

[0111] The control unit 131 sets the Y coordinate Yf of the measurement position measured the second time in step S1F as the initial value of the Y coordinate Yp of the weighted moving average position (step S1J), i.e., Yp=Yf.

[0112] After completing the process of step S1J, the control unit 131 performs the processes of steps S2 to S5A.

[0113] If the control unit 131 determines in step S5A that the distance d is not longer than the predetermined distance dm (S5A: No), it updates the X-direction velocity Xv of the fingertip FT according to equation (11) (step S11A).

[0114]

[0115] Equation (11) is an equation for calculating the X-direction velocity Xv of the fingertip FT based on the difference between the X-coordinate Xf of the most recent measured position and the X-coordinate Xp of the predicted position calculated in the previous control cycle, and for calculating the X-direction velocity using a weighted moving average. More specifically, Equation (11) is an equation for calculating the weighted moving average velocity Xv in the X-direction based on the X-direction velocity Xv calculated in the previous control cycle and the difference (Xf-Xp) between the X-coordinate Xf of the measured position and the X-coordinate Xp of the predicted position calculated in the previous control cycle. Xv on the right side of Equation (11) is the weighted moving average velocity in the X-direction calculated previously. (Xf-Xp) on the right side of Equation (11) is the most recent X-direction velocity. In other words, Equation (11) is an equation for calculating the most recent weighted moving average velocity from the previous weighted moving average velocity and the most recent weighted moving average velocity. The difference (Xf-Xp) between the X coordinate Xf of the measured position and the X coordinate Xp of the predicted position calculated in the previous control cycle can be treated as a speed because it is the difference over one control cycle. The unit of speed in this embodiment is [coordinate change amount / control cycle]. By setting the unit amount of speed to the control cycle (constant cycle), (Xf-Xp) / 1 can be considered as the speed. The division by 1 operation can be omitted.

[0116] In equation (11), k is a predetermined coefficient, and the weight in the exponential moving average is d×k. The smoothing coefficient in equation (11) is (1−d×k). The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A.

[0117] The control unit 131 updates the velocity Yv of the fingertip FT in the Y direction according to equation (12) (step S12A).

[0118]

[0119] Equation (12) is an equation for calculating the Y-direction velocity Yv of the fingertip FT based on the difference between the Y-coordinate Yf of the most recent measured position and the Y-coordinate Yp of the predicted position calculated in the previous control cycle, and for calculating the Y-direction velocity using a weighted moving average. More specifically, Equation (12) is an equation for calculating the Y-direction weighted moving average velocity Yv based on the Y-direction velocity Yv calculated in the previous control cycle and the difference (Yf-Yp) between the Y-coordinate Yf of the measured position and the Y-coordinate Yp of the predicted position calculated in the previous control cycle. Yv on the right side of Equation (12) is the previously calculated weighted moving average velocity in the Y direction. (Xf-Xp) on the right side of Equation (12) is the latest Y-direction velocity. In other words, Equation (12) is an equation for calculating the latest weighted moving average velocity from the previous weighted moving average velocity and the latest weighted moving average velocity. The difference (Yf-Yp) between the Y coordinate Yf of the measured position and the Y coordinate Yp of the predicted position calculated in the previous control cycle can be treated as a speed because it is the difference over the time period of one control cycle. The unit of speed in this embodiment is [coordinate change amount / control cycle]. By setting the unit amount of speed to the control cycle (constant cycle), (Xf-Xp) / 1 can be considered as the speed. The division by 1 operation can be omitted.

[0120] In equation (12), k is a predetermined coefficient, and the weight in the exponential moving average is d×k. The smoothing coefficient in equation (12) is (1−d×k). The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A.

[0121] The control unit 131 calculates the X coordinate Xp of the predicted position in the current control cycle by adding the X coordinate Xp of the predicted position calculated in the previous control cycle and the X-direction velocity Xv calculated in step S11A (step S15). The velocity Xv is the difference in the X coordinate over one control cycle. Therefore, when the X-direction velocity is Xv, the length traveled over one control cycle is Xv. In other words, Xv x 1 is the X-direction distance over one control cycle. The calculation of multiplying by 1 can be omitted.

[0122] The control unit 131 calculates the Y coordinate Yp of the predicted position in the current control cycle by adding the Y coordinate Yp of the predicted position calculated in the previous control cycle and the Y-direction movement speed Yv calculated in step S12A (step S16). The speed Yv is the difference in the Y coordinate over one control cycle. Therefore, when the Y-direction speed is Yv, the length traveled over one control cycle is Yv. In other words, Yv x 1 is the Y-direction distance for one control cycle. The calculation of multiplying by 1 can be omitted.

[0123] The control unit 131 uses the predicted position (Xp, Yp) to display a pointer on the display 110 (step S17). The process of step S17 is the same as the process of step S10 in the process of part 1 (FIG. 3A). The control unit 131 displays the pointer at the predicted position on the display 110.

[0124] When the control unit 131 finishes the process of step S17, the control unit 131 returns the flow to step S2 and repeats the processes of steps S2 to S17.

[0125] Furthermore, if the control unit 131 determines in step S5A that the distance d is longer than the predetermined distance dm (S5A: Yes), it updates the moving speed Xv of the fingertip FT in the X direction according to equation (13) (step S13A).

[0126]

[0127] Equation (13) is an equation in which the distance d in equation (11) is replaced with a predetermined distance dm. In equation (13), k is a predetermined coefficient, and the weight in the exponential moving average is dm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (11).

[0128] If the distance d is longer than the predetermined distance dm, when the moving speed Xv in the X direction is calculated using the weight d×k in equation (11), the weight of the latest speed becomes too small in the calculation of the weighted moving average speed, resulting in little change in the weighted moving average speed Xv. To avoid this, the predetermined distance dm is set as the upper limit of the distance d.

[0129] The control unit 131 updates the moving speed Yv of the fingertip FT in the Y direction according to (14) (step S14A).

[0130]

[0131] Equation (14) is an equation in which the distance d in equation (12) is replaced with a predetermined distance dm. In equation (14), k is a predetermined coefficient, and the weight in the exponential moving average is dm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (12).

[0132] If the distance d is longer than the predetermined distance dm, when the moving speed Yv in the Y direction is calculated using the weight d×k in equation (12), the weight of the latest speed becomes too small in the calculation of the weighted moving average speed, resulting in little change in the weighted moving average speed Yv. To avoid this, the predetermined distance dm is set as the upper limit of the distance d.

[0133] After completing the process of step S14A, the control unit 131 advances the flow to step S15.

[0134] According to the processing (part 3) of the control unit 131, the weighted moving average speeds Xv and Yv are calculated according to the distance d. When calculating the weighted moving average speeds Xv and Yv in equations (11A) and (12A), the shorter the distance d, the greater the weight of the latest speed (Xf-Xp).

[0135] Specifically, when calculating the weighted moving average speeds Xv and Yv, the weight of the weighted moving average speeds Xv and Yv calculated in the previous control cycle is set to d×k, and the weight of the latest speed (the difference (Xf−Xp, Yf−Yp) between the latest measured position and the predicted position calculated in the previous control cycle) is set to (1−d×k).The shorter the distance d, the greater the weight of the latest speed (the difference (Xf−Xp, Yf−Yp) between the latest measured position and the predicted position calculated in the previous control cycle).

[0136] Therefore, when the fingertip FT is close to the operation surface 105A, the weight of the latest velocity (the difference (Xf-Xp, Yf-Yp) between the first position and the predicted position calculated in the previous control cycle) is increased, allowing the pointer position to quickly follow the position of the fingertip FT. Also, when the fingertip FT is away from the operation surface 105A, the weight of the weighted moving average velocities Xv, Yv calculated in the previous control cycle is increased, making it possible to suppress pointer wobble. Also, when the distance d is longer than the predetermined distance dm, the weight is a fixed value of dm×k regardless of the distance d, so the speed at which the pointer position follows the position of the fingertip FT does not become extremely slow. Also, by setting the fixed value (dm×k) to an appropriate size, it is possible to suppress pointer wobble.

[0137] The "pointer wobble" in Part 3 refers to the speed of the pointer. In other words, the processing (Part 3) of the control unit 131 can prevent significant changes in pointer speed due to measurement errors. In particular, for input devices that output speed to control the device using finger speed, a balance between error suppression and speed tracking is important. In particular, for non-contact input devices, changing the balance between error suppression and speed tracking depending on the distance from the sensor electrode to the finger enables output that is closer to the user's intention.

[0138] Although the above describes a configuration in which the weighted moving average velocities Xv and Yv in the X and Y directions are calculated, in a configuration in which operations are performed only along one axis, the weighted moving average velocity along one axis may be calculated. If the measured position on one axis is Pf and the predicted position is Pp, the weighted moving average velocity V can be calculated according to the following equation (15).

[0139]

[0140] <Another Modified Example (Part 4) of the Processing of the Control Unit 131> Figure 3D is a flowchart showing an example of yet another modified example (Part 4) of the processing executed by the control unit 131. In Figure 3D, the same steps as those in Part 3 shown in Figure 3C are assigned the same step numbers. Steps S1A to S1J, S2 to S3, and S15 to S17 in Part 4 are the same as those in Part 3. For this reason, the description will begin with step S4B.

[0141] The control unit 131 calculates the capacitance C between the capacitance type sensor 120 and the fingertip FT based on the difference value ΔAD (step S4B). The process of step S4B is the same as the process of step S4B in part 2.

[0142] The control unit 131 determines whether the capacitance C is smaller than a predetermined capacitance Cm (step S5B). The predetermined capacitance Cm is the upper limit of the capacitance C, and its meaning will be described later. The process of step S5B is the same as the process of step S5B in part 2.

[0143] If the control unit 131 determines that the capacitance C is not smaller than the predetermined capacitance Cm (S5B: No), it updates the moving speed Xv of the fingertip FT in the X direction according to equation (16) (step S11B).

[0144]

[0145] Equation (16) is an equation for calculating the weighted moving average velocity Xv in the X direction of the fingertip FT based on the difference between the X coordinate Xf of the measured position and the predicted position Xp of the fingertip FT calculated in the previous control cycle. More specifically, Equation (16) is an equation for calculating the weighted moving average velocity Xv in the X direction based on the weighted moving average velocity Xv in the X direction calculated in the previous control cycle and the latest velocity (the difference between the X coordinate Xf of the latest measured position and the X coordinate Xp of the predicted position calculated in the previous control cycle).

[0146] In equation (16), k is a predetermined coefficient, and the weight in the exponential moving average is C×k. The smoothing coefficient in equation (16) is C×k. The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A.

[0147] The control unit 131 updates the weighted moving average velocity Yv of the fingertip FT in the Y direction according to equation (17) (step S12B).

[0148]

[0149] Equation (17) is an equation for calculating the weighted moving average velocity Yv in the Y direction of the fingertip FT based on the difference between the Y coordinate Yf of the measured position and the Y coordinate Yp of the predicted position of the fingertip FT calculated in the previous control cycle. More specifically, Equation (17) is an equation for calculating the weighted moving average velocity Yv in the Y direction based on the weighted moving average velocity Yv in the Y direction calculated in the previous control cycle and the latest velocity (the difference between the Y coordinate Yf of the latest measured position and the Y coordinate Yp of the predicted position calculated in the previous control cycle).

[0150] In equation (17), k is a predetermined coefficient, and the weight in the exponential moving average is C×k. The smoothing coefficient in equation (16) is C×k. The value of the predetermined coefficient k may be set to an appropriate value depending on, for example, the sensitivity of the input sensor circuit 125A.

[0151] After completing the process of step S12B, the control unit 131 advances the flow to step S15.

[0152] Furthermore, if the control unit 131 determines in step S5B that the capacitance C is smaller than the predetermined capacitance Cm (S5B: Yes), it updates the moving speed Xv of the fingertip FT in the X direction according to equation (18) (step S13B).

[0153]

[0154] Equation (18) is an equation obtained by replacing the capacitance C in equation (16) with a predetermined capacitance Cm. In equation (18), k is a predetermined coefficient, and the weight in the exponential moving average is Cm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (16).

[0155] If the capacitance C is smaller than the predetermined capacitance Cm, when the moving speed Xv in the X direction is calculated using the weight C×k in equation (18), the weight of the latest speed becomes too small, resulting in little change in the moving speed Xv. To avoid this, the predetermined capacitance Cm, which is the lower limit of the capacitance C, is set.

[0156] The control unit 131 updates the weighted moving average velocity Yv of the fingertip FT in the Y direction according to (19) (step S14B).

[0157]

[0158] Equation (19) is an equation obtained by replacing the distance d in equation (17) with a predetermined capacity Cm. In equation (19), k is a predetermined coefficient, and the weight in the exponential moving average is Cm × k. The value of the predetermined coefficient k is, for example, the same as the predetermined coefficient k in equation (17).

[0159] If the capacitance C is smaller than the predetermined capacitance Cm, when the moving speed Yv in the Y direction is calculated using the weight C×k in equation (17), the weight of the latest speed becomes too small, resulting in little change in the moving speed Yv. To avoid this, the predetermined capacitance Cm, which is the lower limit of the capacitance C, is set.

[0160] After completing the process of step S14B, the control unit 131 advances the flow to step S15.

[0161] According to the processing (part 4) of the control unit 131, the weighted moving average speeds Xv, Yv are calculated based on the weighted moving average speeds Xv, Yv calculated in the previous control cycle and the latest speed (the difference between the latest measured position (Xf, Yf) and the predicted position (Xp, Yp) calculated in the previous control cycle) according to the capacitance C. When calculating the weighted moving average speeds Xv, Yv, in equations (11B) and (12B), the larger the capacitance C, the greater the weight given to the latest speed (the difference (Xf-Xp) between the X-coordinate Xf of the latest measured position and the X-coordinate Xp of the predicted position calculated in the previous control cycle).

[0162] Specifically, when calculating the weighted moving average speeds Xv and Yv, the weight of the weighted moving average speeds Xv and Yv calculated in the previous control cycle is set to (1-C×k), and the weight of the latest speed (the difference (Xf-Xp, Yf-Yp) between the latest measured position and the predicted position calculated in the previous control cycle) is set to C×k. The larger the capacitance C, the greater the weight of the latest speed ((Xf-Xp, Yf-Yp)).

[0163] Therefore, when the fingertip FT is close to the operation surface 105A, the proportion of the latest velocity (the difference (Xf-Xp, Yf-Yp) between the latest measured position and the predicted position calculated in the previous control cycle) is large, and the pointer position can be made to quickly track the position of the fingertip FT. Also, when the fingertip FT is away from the operation surface 105A, the proportion of the weighted moving average velocities Xv, Yv calculated in the previous control cycle increases, and pointer wobble can be suppressed. Also, when the capacitance C is smaller than the predetermined capacitance Cm, the weight is a fixed value of Cm×k regardless of the capacitance C, so the speed at which the pointer position tracks the position of the fingertip FT does not become extremely slow. Also, by setting the fixed value (dm×k) to an appropriate size, pointer wobble can be suppressed.

[0164] The "pointer wobble" in Part 4 refers to the pointer movement speed. In other words, the processing (Part 4) of the control unit 131 can prevent significant changes in the pointer movement speed due to measurement errors. In particular, for input devices that output speed to control the device using finger speed, a balance between error suppression and speed tracking is important. In particular, for capacitive non-contact input devices, changing the balance between error suppression and speed tracking according to the magnitude of the capacitance value enables output that is closer to the user's intention.

[0165] Although the above describes a configuration in which the weighted moving average velocities Xv and Yv in the X and Y directions are calculated, in a configuration in which operations are performed only along one axis, the weighted moving average velocity along one axis may be calculated. If the measured position on one axis is Pf and the predicted position is Pp, the weighted moving average velocity V can be calculated according to the following equation (20).

[0166]

[0167] 4A and 4B are diagrams showing an example of a simulation result of the capacitive non-contact input device 100. Here, the simulation results of the X coordinate Xf of the measurement position calculated by the control unit 131, the X coordinate Xp1 of the weighted moving average position in parts 1 and 2, and the X coordinate Xp2 of the predicted position in parts 3 and 4 will be described.

[0168] 4A and 4B, the horizontal axis represents time and the vertical axis represents the X coordinate. The actual finger position is indicated by a solid line, the X coordinate Xf by a dashed line, the X coordinate Xp1 by a one-dot chain line, and the X coordinate Xp2 by a two-dot chain line.

[0169] FIG. 4A shows an example of a simulation result when the fingertip FT is away from the operation surface 105A, and FIG. 4B shows an example of a simulation result when the fingertip FT is close to the operation surface 105A.

[0170] 4A and 4B, the actual finger position is stationary from time 1 to time 3, moves at a constant speed from time 3 to time 15, stops from time 15 to time 19, and moves while changing speed from time 19 onwards. In such cases, the X coordinate Xf fluctuates due to noise.

[0171] As shown in FIG. 4A, when the fingertip FT is away from the operation surface 105A, the X coordinates Xp1 and Xp2 both have less fluctuation than the X coordinate Xf and follow the actual position of the fingertip FT.

[0172] As shown in FIG. 4B, when the fingertip FT is close to the operation surface 105A, the X coordinates Xp1 and Xp2 both have less fluctuation than the X coordinate Xf, and follow the actual position of the fingertip FT.

[0173] 4A and 4B, when the fingertip FT moves at a constant speed, the X coordinate Xp2 of the predicted position in parts 3 and 4 has a smaller fluctuation range and obtains better results. Also, when the fingertip FT moves while changing its speed, the X coordinate Xp1 of the weighted moving average position in parts 1 and 2 has a smaller fluctuation range and obtains better results.

[0174] For this reason, in applications where the fingertip FT often moves at a constant speed, Part 3 or Part 4 is more suitable than Part 1 or Part 2. When using a product that is operated based on the direction of fingertip FT movement, many people move the fingertip FT at a constant speed. For products that are operated based on the direction of fingertip FT movement, Part 3 or Part 4 control is more suitable. On the other hand, in applications where the fingertip FT often moves while changing speed, Part 1 or Part 2 is more suitable than Part 3 or Part 4. When using a product that is operated based on the position of the fingertip FT, many people repeatedly move and stop the fingertip FT. For products that are operated based on the position of the fingertip FT, Part 1 or Part 2 control is more suitable.

[0175] Although the above description has been given using the distance d, the variation Vari, which will be described later, may be used instead of the distance d.

[0176] <Modification (Part 5) of Processing by Control Unit 131> FIGS. 5A and 5B are flowcharts showing an example of a modification (Part 5) of processing executed by the control unit 131. FIG.

[0177] The control unit 131 acquires a difference value ΔAD as the capacitance at each intersection of the capacitance type sensor 120 from the input sensor circuit 125A (step S101). The difference value ΔAD is a measurement value of the capacitance between the capacitance type sensor 120 and the fingertip FT. The process of step S101 corresponds to the process of step S1A.

[0178] The control unit 131 calculates the measurement position (Xf, Yf) of the fingertip FT based on the difference value ΔAD (step S102). The measurement position (Xf, Yf) is an XY coordinate calculated based on the difference value ΔAD, and therefore may be deviated from the actual position of the fingertip FT due to the influence of noise, etc. The process of step S102 corresponds to the process of step S1B.

[0179] The control unit 131 uses the measurement position (Xf, Yf) to display a pointer on the display 110 (step S103). The control unit 131 displays the pointer at the measurement position (Xf, Yf) on the display 110.

[0180] The control unit 131 assigns the measurement position (Xf, Yf) calculated in step S102 to the measurement position (Xf(1), Yf(1)) (step S104), thereby resulting in Xf(1)=Xf and Yf(1)=Yf.

[0181] The control unit 131 executes an initial loop process from steps S105 to S113. i takes a value from 1 to n. For example, n is 10. The initial loop process is a process of collecting n measurement positions (Xf(i), Yf(i)) by performing n measurements.

[0182] The initial loop process includes, as the first process, a loop process of moving the measurement positions in an array (part 1). The loop process of moving the measurement positions in an array (part 1) is a process of repeatedly performing the process of step S105.

[0183] In step S105, the control unit 131 sets the variable j to i (j=i), assigns Xf(j-1) to the measurement position Xf(j), and assigns Yf(j-1) to the measurement position Yf(j) (step S105). Through this process, Xf(j)=Xf(j-1) and Yf(j)=Yf(j-1).

[0184] For example, in the initial loop processing, when up to the fifth measurement position (Xf(5), Yf(5)) has been acquired, in the loop processing of the measurement position array movement (part 1), the fifth Xf is assigned to the sixth Xf, the fourth Xf is assigned to the fifth Xf, the third Xf is assigned to the fourth Xf, the second Xf is assigned to the third Xf, and the first Xf is assigned to the second Xf. This processing results in Xf(6) = Xf(5), Xf(5) = Xf(4), Xf(4) = Xf(3), Xf(3) = Xf(2), and Xf(2) = Xf(1). A new Xf(1) is acquired in step S107, which will be described later. The same applies to the measurement position Yf(i).

[0185] Control unit 131 acquires difference values ​​ΔAD as capacitances at the respective intersections of capacitance type sensor 120 from input sensor circuit 125A (step S106).

[0186] The control unit 131 calculates the measurement position (Xf, Yf) of the fingertip FT based on the difference value ΔAD (step S107).

[0187] The control unit 131 assigns the measurement position (Xf, Yf) calculated in step S107 to the measurement position (Xf(1), Yf(1)) (step S108), thereby resulting in Xf(1)=Xf and Yf(1)=Yf.

[0188] The control unit 131 performs a calculation process for the variance Vari (step S109). Step S109 is a subroutine process for calculating the variance Vari. Details of the calculation process for the variance Vari will be described later using Figures 6A to 6D. (Note: In the Excel drawing data created by Mr. Kodera, there was a comment that read, "Please change the name of 'Calculate distance d' in the basic application embodiment to a subroutine that calculates 'Variation Vari'." S4A in Figures 3A and 3C, which has been in the basic application, remains unchanged as "Calculate distance d." Please confirm which modification this comment refers to.)

[0189] The variation Vari is a parameter that represents the variation at the measurement position (Xf, Yf), and can be expressed, for example, as the reciprocal of the S / N ratio of the capacitance and noise. The calculation process of the variation Vari is a process of calculating the variation Vari.

[0190] The control unit 131 determines whether the variation Vari is greater than i (step S110).

[0191] If the control unit 131 determines that the variation Vari is greater than i (S110: YES), it sets the variation Vari to i (step S111), thereby achieving Vari=i.

[0192] After completing the process of step S111, the control unit 131 advances the flow to step S112. Note that if the control unit 131 determines in step S110 that the variation Vari is not greater than i (S110: NO), the control unit 131 skips step S111 and advances the flow to step S112.

[0193] The control unit 131 calculates the moving average position (Xp, Yp) (step S112). Step S112 is a subroutine process for calculating the moving average position (Xp, Yp). Details of the calculation process for the moving average position (Xp, Yp) will be described later with reference to FIGS. 7A and 7B.

[0194] The control unit 131 uses the moving average position (Xp, Yp) to display a pointer on the display 110 (step S113). The control unit 131 displays the pointer at the measurement position (Xp, Yp) on the display 110.

[0195] This completes the initial loop process. After completing the initial loop process, the control unit 131 performs a loop process of moving the measurement positions (part 2). The loop process of moving the measurement positions (part 2) is a process of repeatedly performing the process of step S114.

[0196] In step S114, the control unit 131 sets the variable j to n, assigns Xf(j-1) to the measurement position Xf(j), and assigns Yf(j-1) to the measurement position Yf(j) (step S114). Through this process, Xf(j) = Xf(j-1) and Yf(j) = Yf(j-1).

[0197] When the maximum value n of i is 10, in the loop processing of the array movement of the measurement position (part 2), the 9th Xf is substituted for the 10th Xf, the 8th Xf for the 9th Xf, the 7th Xf for the 8th Xf, ..., the 1st Xf is substituted for the 2nd Xf, resulting in Xf(10) = Xf(9), Xf(9) = Xf(8), Xf(8) = Xf(7), ..., Xf(2) = Xf(1). The new Xf(1) is calculated in step S116, which will be described later. The same applies to the measurement position Yf(i).

[0198] Control unit 131 acquires difference values ​​ΔAD as capacitances at the respective intersections of capacitance type sensor 120 from input sensor circuit 125A (step S115).

[0199] The control unit 131 calculates the measurement position (Xf, Yf) of the fingertip FT based on the difference value ΔAD (step S116).

[0200] The control unit 131 assigns the measurement position (Xf, Yf) calculated in step S116 to the measurement position (Xf(1), Yf(1)) (step S117), thereby resulting in Xf(1)=Xf and Yf(1)=Yf.

[0201] The control unit 131 performs a process of calculating the variation Vari (step S118). Step S118 is a subroutine process of calculating the variation Vari, and is the same process as step S109.

[0202] The control unit 131 calculates the moving average position (Xp, Yp) (step S119). Step S119 is the same process as step S112.

[0203] The control unit 131 uses the moving average position (Xp, Yp) to display a pointer on the display 110 (step S120). The control unit 131 displays the pointer at the measurement position (Xp, Yp) on the display 110.

[0204] <Calculation Process of Variation Vari> Next, the subroutine process of the calculation process of variation Vari in steps S109 and S118 will be described with reference to FIGS. 6A to 6D.

[0205] <Calculation process of variation Vari (FIG. 6A)> When performing the calculation process of variation Vari shown in FIG. 6A, the input sensor circuit 125A is configured to output to the control unit 131 not only the maximum value of the capacitances between all intersections of the plurality of sensor electrodes 121X, 121Y and the fingertip FT, but also all capacitances between all intersections of the plurality of sensor electrodes 121X, 121Y and the fingertip FT.

[0206] The control unit 131 calculates Vari using the Int function based on the following equation (21) (step S119A). The Int function is a function that derives an integer calculation result by rounding down values ​​after the decimal point. The numerator of the value substituted into the Int function of equation (21) is a value obtained by multiplying the average value of the capacitance for all intersections by m. m is an integer greater than or equal to 1 and may be set to an appropriate value during the design phase of the capacitive non-contact input device 100. The denominator of the value substituted into the Int function is the capacitance between all intersections and the fingertip FT. The control unit 131 divides the numerator by the denominator, substitutes the value obtained by dividing the numerator by the denominator into the Int function, and calculates the value obtained by adding 1 to the value obtained by the Int function as the variation Vari.

[0207]

[0208] The average value of the capacitance for all intersections can be considered to be the magnitude of noise in the capacitance sensor 120. Furthermore, the maximum capacitance can be considered to be the capacitance between the fingertip FT and the sensor electrodes 121X and 121Y. Therefore, the ratio calculated by equation (21) corresponds to the reciprocal of the S / N ratio. The smaller the S / N ratio, the greater the difference between the capacitance (difference value ΔAD) and the actual capacitance, and the greater the variation in the capacitance (difference value ΔAD). Therefore, the variation Vari can be calculated by equation (21).

[0209] In equation (21), 1 is added to the value of the Int function so that the value of the variation Vari is always equal to or greater than 1. Depending on how the value of the integer m is selected, there may be cases where the value of the variation Vari is always equal to or greater than 1 even without adding 1 to the value of the Int function. In such cases, equation (21) may have a format including only the Int function.

[0210] Furthermore, in equation (21), the Int function is used to obtain an integer result by dividing m times the average value of the capacitances of all intersections by the maximum capacitance, but a function other than the Int function may be used as long as it can obtain an integer result.

[0211] <Calculation Process of Variation Vari ( FIG. 6B )> In the calculation process of variation Vari shown in FIG. 6B , the control unit 131 calculates Vari using the Int function based on the following equation (22) (step S119B). The numerator of the value substituted into the Int function is m times the absolute value of the difference between the latest maximum capacitance and the maximum capacitance acquired one sampling period before. The denominator of the value substituted into the Int function is the latest maximum capacitance. The control unit 131 assigns the value obtained by dividing the numerator by the denominator into the Int function, and adds 1 to the value obtained by the Int function to calculate the variation Vari. Note that, as an example, the sampling period and the control period are assumed to be equal.

[0212]

[0213] The capacitance sensor 120 repeatedly acquires the capacitance (difference value ΔAD) with a sampling period of approximately 0.5 seconds, and it is considered that there is almost no difference, or a very small difference, between the position of the fingertip FT at the timing when the latest capacitance is acquired and the position of the fingertip FT at the timing when the capacitance was acquired one sampling period before. For this reason, the difference between the latest capacitance (difference value ΔAD) and the capacitance (difference value ΔAD) acquired one sampling period before is dominated by the influence of noise.

[0214] The number of capacitances used to calculate the moving average of equation (22) is, for example, about 3 to 10. While equation (21) calculates the variation Vari based on a spatial average, equation (22) calculates the variation Vari based on a temporal average. The magnitude of noise can be measured by using the difference between the latest maximum capacitance and the maximum capacitance acquired one sampling period before.

[0215] <Calculation Process of Variation Vari ( FIG. 6C )> In the calculation process of variation Vari shown in FIG. 6C , the control unit 131 calculates Vari using the Int function based on the following equation (23) (step S119C). The numerator of the value substituted into the Int function is the integer m, and the denominator is the most recent maximum capacitance C. The control unit 131 divides the integer m by the most recent maximum capacitance C, substitutes the result into the Int function, and adds 1 to the value obtained by the Int function to calculate the variation Vari. Note that, as an example, m is the value of capacitance C when fingertip FT touches operation surface 105A.

[0216]

[0217] Since the capacitive non-contact input device 100 is operated with the fingertip FT in a non-contact state, the value of the variation Vari may be calculated based only on the capacitance acquired by the capacitive sensor 120, as shown in equation (23).

[0218] <Calculation Process of Variation Vari ( FIG. 6D )> In the calculation process of variation Vari shown in FIG. 6D , the control unit 131 calculates Vari using the Int function based on the following equation (24) (step S119D). The Int function in equation (24) is substituted with a value obtained by multiplying the cumulative total (Σ) of the change in distance over time between the measurement position (Xf(a+1), Yf(a+1)) and the measurement position (Xf(a), Yf(a)) acquired one sampling period prior by an integer m, and then adding 1 to the result. a represents the sampling period and can take values ​​from 1 to 10, for example. Note that m is an integer equal to or greater than 1 and may be set to an appropriate value during the design phase of the capacitive non-contact input device 100.

[0219]

[0220] The smaller the S / N ratio, the larger the difference between the capacitance (difference value ΔAD) and the actual capacitance, and the larger the variation in the capacitance (difference value ΔAD). This tends to increase the deviation between the measurement position (Xf(a), Yf(a)) and the actual position of the fingertip FT. As with equation (22), the difference between the positions of the fingertip FT acquired at timings that differ by one sampling period is considered to be almost nonexistent or very small. Therefore, the distance between the measurement position (Xf(a+1), Yf(a+1)) and the measurement position (Xf(a), Yf(a)) acquired one sampling period earlier is significantly affected by noise. Therefore, the variation Vari can be calculated by substituting the cumulative total (Σ) of the distance over time into equation (24).

[0221] Note that the measurement positions (Xf(a), Yf(a)) are two-dimensional positions, but the cumulative total (Σ) of the change in distance over time calculated using the three-dimensional measurement positions may be substituted into equation (24).

[0222] Furthermore, instead of the cumulative total (Σ) of the distance change over time, a moving average of the differences between the measurement positions (Xf(a), Yf(a)) acquired at multiple consecutive sampling times may be used.

[0223] <Calculation Process of Moving Average Position (Xp, Yp)> Next, the subroutine process of the calculation process of the moving average position (Xp, Yp) in steps S112 and S120 will be described with reference to FIGS. 7A to 8. FIG.

[0224] <Calculation Process of Moving Average Position (Xp, Yp) (FIG. 7A)> FIG. 7A shows an example of a process of calculating the moving average position (Xp, Yp) by simple moving averaging.

[0225] The control unit 131 calculates the moving average position (Xp, Yp) by calculating a simple moving average of the X and Y coordinates for a predetermined number of past measurement positions (Xf(k), Yf(k)) that are continuously acquired at each sampling period starting from the most recent measurement position (Xf(k), Yf(k)) based on the following equations (25) and (26) (steps S121A and S122A). The predetermined number is, for example, a number represented by the value of the variation Vari.

[0226]

[0227]

[0228] <Calculation Process of Moving Average Position (Xp, Yp) (FIG. 7B)> FIG. 7B shows an example of a process of calculating the moving average position (Xp, Yp) by linear weighted moving averaging.

[0229] The control unit 131 calculates the moving average position (Xp, Yp) by calculating a linear weighted moving average of the X coordinate and the Y coordinate for a predetermined number of past measurement positions (Xf(k), Yf(k)) that are continuously acquired at each sampling period starting from the most recent measurement position (Xf(k), Yf(k)) based on the following equations (27) and (28) (steps S121B and S122B). The predetermined number is, for example, a number represented by the value of the variation Vari.

[0230]

[0231]

[0232] <Calculation Process of Moving Average Position (Xp, Yp) (FIG. 7C)> FIG. 7C shows an example of a process for calculating the moving average position (Xp, Yp) by simple moving averaging. FIG. 7C shows a method for calculating the moving average position (Xp, Yp) by simple moving averaging that is different from that shown in FIG. 7A. FIG. 7C shows a method for calculating the moving average position (Xp, Yp) for all possible values ​​of the variation Vari each time a measurement is performed, and selecting the moving average position (Xp, Yp) according to the actual value of Vari. When the possible values ​​of the variation Vari are small, the calculation method shown in FIG. 7C may require less calculation effort than the calculation method shown in FIG. 7A.

[0233] The calculation method of Fig. 7C requires n+1 arrays, so step S141A of Fig. 8 is executed instead of step S114 of Fig. 5B. In step S114A, the control unit 131 sets the variable j to n+1, assigns Xf(j-1) to the measurement position Xf(j), and assigns Yf(j-1) to the measurement position Yf(j) (step S114A). This process results in Xf(j) = Xf(j-1) and Yf(j) = Yf(j-1).

[0234] The control unit 131 substitutes the latest measured positions (Xf(1), Yf(1)) into the moving average positions (Xp(1), Yp(1)) using the following equations (29) and (30) (steps S121C, S122C).

[0235]

[0236]

[0237] The control unit 131 calculates the moving average position (Xp(2), Yp(2)) using the following equations (31) and (32) (steps S123C and S124C).

[0238]

[0239]

[0240] The control unit 131 calculates the latest moving average position Xp(2) by swapping the oldest measurement position Xf(3) of the multiple measurement positions Xf used in the calculation of the moving average position Xp(2) in the previous calculation with the latest measurement position Xf(1) in accordance with equation (31). More specifically, the control unit 131 calculates the latest moving average position Xp(2) by subtracting Xf(3) / 2 from the previously calculated moving average position Xp(2) and adding Xf(1) / 2 in accordance with equation (31).

[0241] In addition, the control unit 131 calculates the latest moving average position Yp(2) by subtracting Yf(3) / 2 from the previously calculated moving average position Yp(2) and adding Yf(1) / 2 according to equation (32).

[0242] The control unit 131 calculates the moving average position (Xp(3), Yp(3)) using the following equations (33) and (34) (steps S125C and S126C).

[0243]

[0244]

[0245] The control unit 131 calculates the latest moving average position Xp(3) by swapping the oldest measurement position Xf(4) of the multiple measurement positions Xf used in the calculation of the moving average position Xp(3) in the previous calculation with the latest measurement position Xf(1) in accordance with equation (33). More specifically, the control unit 131 calculates the latest moving average position Xp(3) by subtracting Xf(4) / 3 from the previously calculated moving average position Xp(3) and adding Xf(1) / 3 in accordance with equation (33).

[0246] In addition, the control unit 131 calculates the latest moving average position Yp(3) by subtracting Yf(4) / 3 from the previously calculated moving average position Yp(3) and adding Yf(1) / 3 according to equation (34).

[0247] If there is a moving average position (Xp(4), Yp(4)) from the previously calculated moving average position (Xp(10), Yp(10)), the control unit 131 performs calculations similar to steps S123C, S124C, and steps S125C and S126C.

[0248] The calculation method for such a moving average position (Xp, Yp) can be expressed by the following general formula:

[0249] The control unit 131 calculates the moving average position (Xp(n), Yp(n)) using the following equations (35) and (36) (steps S131C and S132C). For example, n can range from 1 to the value of the variation Vari.

[0250]

[0251]

[0252] The control unit 131 substitutes the moving average position (Xp(Vari), Yp(Vari)) for the moving average position (Xp, Yp) in accordance with the following equations (37) and (38) (steps S133C and S133C).

[0253]

[0254]

[0255] As described above with reference to FIGS. 5A to 8, in addition to the exponential moving average, a simple moving average or a weighted moving average can be used as the moving average.

[0256] <Effects> The capacitive non-contact input device 100 of the present disclosure includes a plurality of sensor electrodes 121X, 121Y arranged along a plane on the back side of the operation surface 105A, an input sensor circuit 125A that measures the capacitance between each of the plurality of sensor electrodes 121X, 121Y and the fingertip FT, and a control unit 131. The control unit 131 calculates a measurement position (Xf, Yf), which is the planar position of the fingertip FT, and a variance Vari of the measurement position (Xf, Yf), based on the capacitance measured by the input sensor circuit 125A, calculates a moving average position, which is the planar position of the fingertip FT, based on a moving average of the measurement positions (Xf, Yf) at multiple points in time, and, when calculating the moving average position (Xp, Yp), increases the weight of the most recent measurement position (Xf, Yf) in the moving average as the variance Vari decreases. Therefore, when the fingertip FT is close to the operation surface 105A, the weight of the latest measured position (Xf, Yf) is increased, and the position of the pointer can be made to follow the position of the fingertip FT. Also, when the fingertip FT is far from the operation surface 105A, the weight of the latest measured position (Xf, Yf) is decreased, and it is possible to suppress the wobbling of the pointer.

[0257] Therefore, it is possible to provide a capacitive non-touch input device 100 that can smoothly move the position (weighted moving average position) calculated for displaying the pointer according to the position of the indicator.

[0258] In addition, the moving average may be an exponential moving average, and the control unit 131 may calculate the latest moving average position (Xp, Yp) for each control cycle using the latest measured position (Xf, Yf) and the moving average position (Xp, Yp) calculated in the previous control cycle.

[0259] In the exponential moving average, the amount of calculation and storage required can be reduced by using the previous moving average value.

[0260] Another capacitive non-contact input device 100 of the present disclosure includes a plurality of sensor electrodes 121X, 121Y arranged along a plane on the back side of an operation surface 105A, an input sensor circuit 125A that acquires measured values ​​of capacitance between each of the plurality of sensor electrodes 121X, 121Y and a fingertip FT, and a control unit 131. The control unit 131 calculates a measurement position (Xf, Yf), which is the planar position of the fingertip FT, and a calculated value of the capacitance between the plurality of sensor electrodes 121X, 121Y and the fingertip FT, based on the measured capacitance values ​​acquired by the input sensor circuit 125A, calculates a moving average position, which is the planar position of the fingertip FT, based on a moving average of the measured positions at multiple points in time, and when calculating the moving average position (Xp, Yp), the larger the calculated value of the capacitance, the greater the weight of the most recent position (Xf, Yf) in the moving average. Therefore, when the fingertip FT is close to the operation surface 105A, the proportion of the most recent measured position (Xf, Yf) is high, and the position of the pointer can be made to follow the position of the fingertip FT. Also, when the fingertip FT is away from the operation surface 105A, the weight of the most recent measured position (Xf, Yf) becomes small, and it is possible to suppress the wobbling of the pointer.

[0261] Therefore, it is possible to provide a capacitive non-touch input device 100 that can smoothly move the position (weighted moving average position) calculated for displaying the pointer according to the position of the indicator.

[0262] In addition, the moving average may be an exponential moving average, and the control unit 131 may calculate the moving average position (Xp, Yp) for each control cycle based on the measurement position (Xf, Yf) and the moving average position (Xp, Yp) calculated in the previous control cycle.

[0263] In the exponential moving average, the amount of calculation and storage required can be reduced by using the previous moving average value.

[0264] Another capacitive non-contact input device 100 of the present disclosure includes a plurality of sensor electrodes 121X, 121Y arranged along a plane on the rear side of an operation surface 105A, an input sensor circuit 125A that measures capacitance between each of the plurality of sensor electrodes 121X, 121Y and a fingertip FT, and a control unit 131. The control unit 131 calculates a measurement position (Xf, Yf) that is a plane position of the fingertip FT and a variance Vari of the measurement position (Xf, Yf) based on the capacitance measured by the input sensor circuit 125A for each control period. The system calculates the moving average velocity of the fingertip FT for each control cycle based on the velocity calculated based on the moving average of the difference between the measured position (Xf, Yf) and the predicted position (Xp, Yp), which is the planar position of the fingertip FT calculated in the previous control cycle. The system calculates the predicted position (Xp, Yp) for the current control cycle based on the predicted position (Xp, Yp) calculated in the previous control cycle and the moving average velocity. When calculating the moving velocity, the smaller the variance (Vari), the larger the weighting coefficient of the latest velocity in the moving average. Therefore, when the fingertip FT is close to the operation surface 105A, the weight of the latest velocity (the difference (Xf-Xp, Yf-Yp) between the measured position and the predicted position calculated in the previous control cycle) is increased, allowing the position of the pointer to track the position of the fingertip FT. Furthermore, when the fingertip FT is farther from the operation surface 105A, the weight of the latest velocity is reduced, thereby suppressing pointer wobble.

[0265] Therefore, it is possible to provide a capacitive non-touch input device 100 that can smoothly move the position (predicted position) calculated for displaying the pointer in accordance with the position of the indicator.

[0266] In addition, the moving average may be an exponential moving average, and the control unit 131 may calculate the moving average speed for each control cycle based on the moving average speed calculated in the previous control cycle and the difference between the measured position and the predicted position (Xp, Yp) calculated in the previous control cycle.

[0267] In the exponential moving average, the amount of calculation and storage can be reduced by using the previous weighted moving average value.

[0268] Another capacitive non-contact input device 100 of the present disclosure includes a plurality of sensor electrodes 121X, 121Y arranged along a plane on the rear side of an operation surface 105A, an input sensor circuit 125A that measures capacitance between each of the plurality of sensor electrodes 121X, 121Y and a fingertip FT, and a control unit 131. The control unit 131 determines, for each control period, based on the capacitance measured by the input sensor circuit 125A, a measurement position (Xf, Yf) that is a planar position of the fingertip FT, and a capacitance between the plurality of sensor electrodes 121X, 121Y and the fingertip FT. The system calculates a calculated capacitance value, and for each control cycle, calculates the moving average velocity of the fingertip FT based on a moving average of velocities calculated based on the difference between the measured position (Xf, Yf) and the predicted position (Xp, Yp), which is the planar position of the fingertip FT calculated in the previous control cycle. The system calculates a predicted position (Xp, Yp) for the current control cycle based on the predicted position (Xp, Yp) calculated in the previous control cycle and the moving average velocity. When calculating the moving velocity, the larger the calculated capacitance value, the larger the weighting coefficient for the most recent velocity in the moving average. Therefore, when the fingertip FT is close to the operation surface 105A, the weighting coefficient for the most recent velocity (the difference (Xf-Xp, Yf-Yp) between the most recent position and the predicted position calculated in the previous control cycle) is increased, allowing the pointer position to track the position of the fingertip FT. Furthermore, when the fingertip FT is far from the operation surface 105A and the capacitance C is greater than a predetermined capacitance Cm, the weighting coefficient for the most recent velocity is reduced, thereby suppressing pointer wobble.

[0269] Therefore, it is possible to provide a capacitive non-touch input device 100 that can smoothly move the position (predicted position) calculated for displaying the pointer in accordance with the position of the indicator.

[0270] In addition, the moving average may be an exponential moving average, and the control unit 131 may calculate the moving average speed for each control cycle based on the moving average speed calculated in the previous control cycle and the difference between the measured position (Xf, Yf) and the predicted position (Xp, Yp) calculated in the previous control cycle.

[0271] The calculated capacitance value may be a value measured when there is a virtual sensor electrode of a predetermined size centered on the measurement position (Xf, Yf) in a plane including multiple sensor electrodes. Even when each capacitance sensor is large and the error is large when the position of the capacitance sensor is considered to be the position of the fingertip FT, the position of the fingertip FT can be calculated with high accuracy.

[0272] The capacitance measured by the input sensor circuit 125A may be the maximum value of the capacitance between each of the plurality of sensor electrodes 121X and 121Y and the fingertip FT, which allows the capacitance to be calculated easily.

[0273] Furthermore, among line segments that are perpendicular to the sensor surface including the surfaces of the plurality of sensor electrodes 121X and 121Y, and have one end point at the position on the sensor surface and the other end point at a position where the fingertip FT makes contact, the end point on the sensor surface of the shortest line segment may be regarded as the measurement position (Xf, Yf), and the length of the shortest line segment may be regarded as the variation Vari. By regarding the position on the surface of the fingertip FT that is closest to the operation surface 105A as the position of the fingertip FT, it is possible to indicate the position intended by the user.

[0274] Furthermore, the control unit 131 may calculate the variation Vari based on the maximum value of the capacitance between each of the plurality of sensor electrodes 121X and 121Y and the fingertip FT. In this way, the variation Vari can be easily calculated.

[0275] Furthermore, the control unit 131 may set the weight to a constant value when the variation Vari exceeds a predetermined value. In order to prevent the pointer position from becoming less responsive to the position of the fingertip FT when the variation Vari is longer than the predetermined value, a predetermined value is set as an upper limit of the variation Vari.

[0276] The control unit 131 may set the weight to a constant value when the calculated value of the capacitance C is less than a predetermined capacitance Cm. In order to prevent the pointer speed from deteriorating in response to the finger speed when the capacitance C is smaller than the predetermined capacitance Cm, the predetermined capacitance Cm is set as the lower limit of the capacitance C.

[0277] The variation in the planar position of the fingertip FT is the distance between the multiple sensor electrodes 121X, 121Y and the fingertip FT, and when calculating the moving average position, the control unit 131 may increase the weighting coefficient of the most recently measured position in the moving average as the distance decreases. When the fingertip FT is closer to the operation surface 105A, the weight of the most recently measured position (Xf, Yf) increases, allowing the position of the pointer to follow the position of the fingertip FT.

[0278] The moving average may be a simple moving average. When calculating the moving average position based on the simple moving average, the number of values ​​used in the calculation is reduced when the fingertip FT is close to the operation surface 105A. In other words, when the fingertip FT is close to the operation surface 105A, only relatively recent values ​​are used, which increases the weight of the most recent measured position (Xf, Yf), allowing the pointer position to follow the position of the fingertip FT. Conversely, when the fingertip FT is far from the operation surface 105A, the influence of errors can be suppressed by calculating the average position using many values, from newest to oldest.

[0279] The moving average may be a weighted moving average. When a weighted moving average is used, the number of values ​​used in the calculation is changed depending on the distance from the fingertip FT to the operation surface 105A. When the fingertip FT is close to the operation surface 105A, the weight of the most recent measured position (Xf, Yf) is increased by reducing the number of values ​​used in the calculation, and the pointer position can be made to track the position of the fingertip FT. Conversely, when the fingertip FT is far from the operation surface 105A, the influence of errors can be suppressed by increasing the number of values ​​used in the calculation. In the weighted moving average, the weight of the most recent measured position (Xf, Yf) is large, and therefore tracking ability is high.

[0280] The variation in the measurement position (Xf, Yf) may be the reciprocal of the S / N ratio. The variation expressed as the reciprocal of the S / N ratio can be easily calculated, and the capacitance-type non-contact input device 100 can be provided, which is capable of smoothly moving the position (weighted moving average position) calculated for displaying the pointer according to the position of the indicator.

[0281] The variation in the measurement position (Xf, Yf) may be the ratio of the total capacitance of all of the plurality of sensor electrodes 121X, 121Y to the maximum capacitance of the plurality of sensor electrodes 121X, 121Y. The variation expressed as the ratio of the total capacitance of all of the plurality of sensor electrodes 121X, 121Y to the maximum capacitance of the plurality of sensor electrodes 121X, 121Y can be easily calculated, and the capacitive non-contact input device 100 can be provided that is capable of smoothly moving the position (weighted moving average position) calculated for displaying the pointer in accordance with the position of the indicator.

[0282] The variation in the measurement position (Xf, Yf) may be a moving average of a plurality of distances calculated in successive control cycles. The variation represented by the moving average of a plurality of distances calculated in successive control cycles can be easily calculated, and the capacitive non-contact input device 100 can be provided, which is capable of smoothly moving the position (weighted moving average position) calculated for displaying the pointer in accordance with the position of the indicator.

[0283] The exponential moving average may be calculated as a power series using measurements from multiple points in time, i.e., using the distance d, it may be calculated as follows:

[0284] However, P ｆ is the latest measurement position, P ｆ―１ is the previous measurement position, P ｆ―２ is the measurement position two times before, P ｆ―ｎ indicates the measurement position n times before, and k is a predetermined coefficient. The smoothing coefficient (1-d×k) is smaller than 1, and the magnitude becomes negligible from a certain term onward, so calculations may be performed using a predetermined number of values.

[0285] Similarly, when using capacitance C, the exponential moving average may be calculated as a power series using measurements at multiple points in time.

[0286] However, P ｆ is the latest measurement position, P ｆ―１ is the previous measurement position, P ｆ―２ is the measurement position two times before, P ｆ―ｎindicates the measurement position n times before, and k is a predetermined coefficient. Furthermore, since the smoothing coefficient c×k is smaller than 1 and becomes negligible from a certain term onward, calculation may be performed using a predetermined number of values.

[0287] The formula for calculating the exponential moving average may be any formula other than that described in the embodiment, as long as it can calculate the same value. For example, the following formula can also calculate the same value as in the embodiment.

[0288]

[0289] The above describes a non-contact input device according to an exemplary embodiment of the present disclosure. However, the present disclosure is not limited to the specifically disclosed embodiment, and various modifications and variations are possible without departing from the scope of the claims.

[0290] This international application claims priority based on Japanese Patent Application No. 2024-120430, filed on July 25, 2024, the entire contents of which are incorporated herein by reference.

[0291] REFERENCE SIGNS LIST 100 Capacitive non-contact input device 101 Housing 105 Top panel 105A Operation surface 110 Display 120 Capacitive sensor 121X, 121Y Sensor electrode 125 Wiring board 125A Input sensor circuit 125B Image display circuit 130 Control device 131 Control unit 132 Memory

Claims

1. A capacitive non-touch input device comprising: a plurality of sensor electrodes arranged along a plane on the rear side of an operation surface; a measurement circuit that measures the capacitance between each of the plurality of sensor electrodes and an indicator; and a control unit, wherein the control unit calculates a measurement position, which is the planar position of the indicator, and a variance in the measurement position based on the capacitance measured by the measurement circuit; calculates a moving average position, which is the planar position of the indicator, based on a moving average of the measurement positions at a plurality of points in time; and when calculating the moving average position, the smaller the variance, the larger the weighting coefficient of the most recent measurement position in the moving average.

2. The capacitive non-contact input device according to claim 1, wherein the moving average is an exponential moving average, and the control unit calculates the latest moving average position for each control cycle using the latest measured position and the moving average position calculated in the previous control cycle.

3. A capacitive non-touch input device comprising: a plurality of sensor electrodes arranged along a plane on the back side of an operation surface; a measurement circuit that acquires measured values ​​of capacitance between each of the plurality of sensor electrodes and an indicator; and a control unit, wherein the control unit calculates a measurement position, which is the planar position of the indicator, and a calculated value of the capacitance between the plurality of sensor electrodes and the indicator based on the measured values ​​of capacitance acquired by the measurement circuit; calculates a moving average position, which is the planar position of the indicator, based on a moving average of the measured positions at a plurality of points in time; and when calculating the moving average position, the larger the calculated value of the capacitance, the larger the weighting coefficient of the most recent measured position in the moving average.

4. The capacitive non-contact input device according to claim 3, wherein the moving average is an exponential moving average, and the control unit calculates the moving average position for each control cycle based on the measured position and the moving average position calculated in the previous control cycle.

5. A capacitive non-touch input device comprising: a plurality of sensor electrodes arranged along a plane on the back side of an operation surface; a measurement circuit that measures the capacitance between each of the plurality of sensor electrodes and an indicator; and a control unit, wherein the control unit calculates, for each control cycle, a measured position, which is the planar position of the indicator, and a variance in the measured position, based on the capacitance measured by the measurement circuit; calculates, for each control cycle, a moving average speed of the indicator based on a speed calculated based on a moving average of the difference between the measured position and a predicted position, which is the planar position of the indicator calculated in the previous control cycle; calculates the predicted position in the current control cycle based on the predicted position calculated in the previous control cycle and the moving average speed; and when calculating the moving average speed, the smaller the variance, the larger the weighting coefficient of the latest speed in the moving average.

6. A capacitive non-contact input device as described in claim 5, wherein the moving average is an exponential moving average, and the control unit calculates the moving average speed for each control cycle based on the moving average speed calculated in the previous control cycle and the difference between the measured position and the predicted position calculated in the previous control cycle.

7. A capacitive non-touch input device comprising: a plurality of sensor electrodes arranged along a plane on the back side of an operation surface; a measurement circuit that measures the capacitance between each of the plurality of sensor electrodes and an indicator; and a control unit, wherein the control unit calculates, for each control cycle, a measured position that is the planar position of the indicator and a calculated value of the capacitance between the plurality of sensor electrodes and the indicator based on the capacitance measured by the measurement circuit; calculates, for each control cycle, a moving average speed of the indicator based on a moving average of speeds calculated based on the difference between the measured position and a predicted position that is the planar position of the indicator calculated in the previous control cycle; calculates the predicted position in the current control cycle based on the predicted position calculated in the previous control cycle and the moving average speed; and when calculating the speed, the larger the calculated value of the capacitance, the larger the weighting coefficient of the latest speed in the moving average.

8. A capacitive non-contact input device as described in claim 7, wherein the moving average is an exponential moving average, and the control unit calculates the moving average speed for each control cycle based on the moving average speed calculated in the previous control cycle and the difference between the measured position and the predicted position calculated in the previous control cycle.

9. A capacitive non-contact input device according to any one of claims 3, 4, 7 and 8, wherein the calculated value of the capacitance is a calculated value measured when there is a virtual sensor electrode of a predetermined size centered on the measurement position within a plane including the plurality of sensor electrodes.

10. A capacitive non-contact input device according to any one of claims 1 to 8, wherein the capacitance measured by the measurement circuit is the maximum value of the capacitance between each of the plurality of sensor electrodes and the indicator.

11. A capacitive non-contact input device as described in any one of claims 1, 2, 5 and 6, wherein the measurement position is regarded as the endpoint on the sensor surface of the shortest line segment among line segments that are perpendicular to the sensor surface including the surfaces of the plurality of sensor electrodes, and have the position of the sensor surface as one endpoint and the position where the indicator is in contact as the other endpoint, and the length of the shortest line segment is regarded as the variation.

12. A capacitive non-contact input device as described in any one of claims 1, 2, 5 and 6, wherein the control unit calculates the variation based on the maximum value of the capacitance between each of the plurality of sensor electrodes and the indicator.

13. A capacitive non-contact input device as described in any one of claims 1, 2, 5 and 6, wherein the control unit sets the weighting coefficient to a constant value when the variation exceeds a predetermined value.

14. A capacitance-type non-contact input device as described in any one of claims 3, 4, 7 and 8, wherein the control unit sets the weighting coefficient to a constant value when the calculated value of the capacitance is less than a predetermined value.

15. A capacitive non-contact input device as described in any one of claims 1, 2, 5 and 6, wherein the variation in the measurement position is the distance between the multiple sensor electrodes and the indicator, and when calculating the moving average position, the control unit increases the weighting coefficient of the most recent measurement position in the moving average as the distance becomes shorter.

16. The capacitive non-touch input device according to claim 15, wherein the moving average is a simple moving average.

17. The capacitive non-touch input device according to claim 15, wherein the moving average is a weighted moving average.

18. A capacitive non-contact input device according to any one of claims 1, 2, 5 and 6, wherein the variation in measurement position is the reciprocal of the S / N ratio.

19. A capacitive non-contact input device according to claim 18, wherein the variation in measurement position is the ratio of the total capacitance of all of the plurality of sensor electrodes to the maximum capacitance of the plurality of sensor electrodes.

20. The capacitive non-contact input device according to claim 15, wherein the variation in the measured position is a moving average of a plurality of the distances calculated in successive control periods.

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