Non-contact input device

Abstract

This invention provides a contactless input device capable of determining whether a contactless operation has occurred and the location of the operation. The contactless input device includes: a plurality of sensor electrodes for detecting electrostatic capacitance corresponding to the approach state of a hand performing a contactless operation input to the operation surface of an operating unit; and a determination unit that, based on the electrostatic capacitance detected by the plurality of sensor electrodes, calculates the sharpness of the hand at multiple different locations in a top-view perspective, and determines the location of the operation input based on the plurality of sharpness values.

Description

Technical Field

[0001] This invention relates to contactless input devices. Background Technology

[0002] Conventionally, there exists a touchpad input device with a control unit that has a palm rejection function that determines whether the contact area of ​​an object, calculated by detecting changes in electrical variables caused by an object approaching the operating surface, is based on the area of ​​the fingertip or the palm. The determination of whether the operation was performed using the fingertip or the palm is based on the area of ​​the contact area (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2015-141425 Summary of the Invention

[0006] -The problem the invention aims to solve-

[0007] Traditional touchpad input devices rely on hand contact with the touchpad surface. However, there are situations where it is desirable to input data without touching the touchpad surface.

[0008] Therefore, the object of the present invention is to provide a non-contact input device capable of determining whether there is a non-contact operation and the location of the operation.

[0009] The contactless input device according to an embodiment of the present invention includes: a plurality of sensor electrodes for detecting electrostatic capacitance corresponding to a hand approaching the operation surface of the operation unit in a contactless operation input state; and a determination unit for calculating the sharpness of the hand at multiple different positions when viewed from above based on the electrostatic capacitance detected by the plurality of sensor electrodes, and determining the position of the operation input based on the plurality of sharpnesses.

[0010] -Invention Effects-

[0011] It can provide a non-contact input device that can determine whether there is a non-contact operation and the location of the operation. Attached Figure Description

[0012] Figure 1 This is a diagram illustrating an example of the structure of an electronic device 100 including a contactless input device according to an embodiment.

[0013] Figure 2 This is a diagram illustrating an example of the structure of an electronic device 100 including a contactless input device according to an embodiment.

[0014] Figure 3 This is a diagram illustrating an example of the structure of an electronic device 100 including a contactless input device according to an embodiment.

[0015] Figure 4 This is a diagram illustrating an example of the structure of the contactless input device 100A in an embodiment.

[0016] Figure 5 This is a graph showing an example of the distribution of the difference value ΔAD and its reciprocal for the relationship between the hand H and the electrode surface of the electrostatic sensor 120.

[0017] Figure 6 This is a diagram illustrating an example of the distribution of the reciprocals of the hand H along its length and width.

[0018] Figure 7 This is a graph illustrating the quadratic coefficients of the quadratic curves fitted to the fingertip FT and the palm P.

[0019] Figure 8 This is a flowchart illustrating the process of determining the position of the fingertip FT.

[0020] Figure 9 This is a flowchart illustrating the process of determining the position of the fingertip FT.

[0021] Figure 10 This is a flowchart illustrating the process of determining the position of the fingertip FT.

[0022] Figure 11 This is a flowchart illustrating the process of determining the position of the fingertip FT.

[0023] Figure 12 This is a flowchart illustrating the process of determining the position of the fingertip FT.

[0024] Figure 13 This is a flowchart illustrating the process of determining the position of the fingertip FT.

[0025] Figure 14 It is a graph representing the distribution of the difference ΔAD, the distribution of the reciprocal, and column j, which gives the minimum value of the reciprocal represented by Column(i), Minimum(i).

[0026] Figure 15 It is a graph representing the object for calculating sharpness, the minimum value Minimum(i), the result of the sharpness calculation, the maximum sharpness, and the coordinates.

[0027] Figure 16 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the first variant.

[0028] Figure 17 This is a graph showing the relationship between the xz coordinates and the fingertip FT.

[0029] Figure 18 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the second variation.

[0030] Figure 19 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the third variation.

[0031] Figure 20 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-finger tip determination" of the fourth variant.

[0032] Figure 21 This is a flowchart illustrating the process of determining the position of the fingertip FT in the fifth variation.

[0033] Figure 22 This is a flowchart illustrating the process of determining the position of the fingertip FT in the fifth variation.

[0034] Figure 23 This is a flowchart illustrating the process of determining the position of the fingertip FT in the fifth variation.

[0035] Figure 24 It is a graph showing the order of the difference values ​​ΔAD obtained from the sensor electrodes 121 in rows of 5 and columns of 6, the absolute value of the variance of BigX(i), and the absolute value of the covariance of BigX(i) and BigY(i).

[0036] Figure 25 It means Figure 20 The diagram shows the determination result in the processing of the fingertip in the fourth variation example.

[0037] Figure 26 This is a flowchart illustrating the process of determining the position of the fingertip FT in the sixth variation.

[0038] Figure 27 This is a flowchart illustrating the process of determining the position of the fingertip FT in the sixth variation.

[0039] Figure 28 This is a flowchart illustrating the process of determining the position of the fingertip FT in the sixth variation.

[0040] Figure 29 This is a flowchart illustrating the process of determining the position of the fingertip FT in the sixth variation.

[0041] Figure 30This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the seventh variation.

[0042] Figure 31 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the eighth variant.

[0043] Figure 32 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the ninth variation.

[0044] Figure 33 This is a diagram showing the specific structure of the electrostatic sensor 120 of the non-contact input device 100A.

[0045] -Explanation of Figure Markers-

[0046] 100 Electronic devices

[0047] 100A Contactless Input Device

[0048] 105 Operating Surface

[0049] 110 display device

[0050] 120 Electrostatic Sensor

[0051] 121, 121X, 121Y sensor electrodes

[0052] 122, 122X, 122Y wiring

[0053] 130 Control Device

[0054] 131 Main Control Unit

[0055] 132 AD Conversion Unit

[0056] 133 counter

[0057] 134 Judgment Department

[0058] 135 Motion Control Department

[0059] 136 Display Control Department

[0060] 137 Memory Detailed Implementation

[0061] Hereinafter, embodiments of the contactless input device using the present invention will be described.

[0062] <Implementation Method>

[0063] Figure 1 , Figure 2 as well as Figure 3 This is a diagram illustrating an example of the structure of an electronic device 100 including a contactless input device according to an embodiment. Figure 4 This is a diagram illustrating an example of the structure of the contactless input device 100A according to an embodiment. Figure 2 as well as Figure 3 The image shows the hand H of a user of the electronic device 100. More specifically, the fingertip FT and palm P of the hand H are shown. The fingertip FT is, for example, the index finger, but it can also be any finger other than the index finger.

[0064] The following explanation uses an XYZ coordinate system. The directions parallel to the X-axis (X direction), the Y-axis (Y direction), and the Z-axis (Z direction) are orthogonal to each other. Furthermore, the -Z direction is described as the direction approaching the electrostatic sensor 120, and the +Z direction as the direction away from the electrostatic sensor 120. Also, "top view" refers to observation in the XY plane. Additionally, the length, thickness, and other dimensions of various parts may be exaggerated for easier understanding of the structure.

[0065] Electronic device 100 includes a housing 101, a display device 110, an electrostatic sensor 120, and a control device 130. Although in Figures 1 to 3 The control device 130 is omitted (see reference). Figure 4 However, as an example, the control device 130 is disposed inside the housing 101 below the display device 110 and the electrostatic sensor 120. Figure 4 As shown, the contactless input device 100A includes an electrostatic sensor 120 and a control device 130.

[0066] The housing 101 is a shell made of resin or metal that houses the display device 110, the electrostatic sensor 120, and the control device 130. As an example, the display device 110 is disposed below the transparent electrostatic sensor 120 and can be visually identified through the upper surface of the transparent panel or the like, i.e., the operation surface 105, which is provided in the opening at the top of the housing 101.

[0067] The electronic device 100 can be operated without the fingertip FT and palm P coming into contact with the operating surface 105 of the electronic device 100, or by bringing the fingertip FT and palm P close to the operating surface 105 without contact. Figure 2 as well as Figure 3 As an example, it is shown that the distance D from the operating surface 105 (see reference) is utilized. Figure 2The electronic device 100 detects the position of the fingertip FT that is not in contact with the operation surface 105 and accepts non-contact operation input. Non-contact operation input refers to operating the electronic device 100 using the fingertip FT without the fingertip FT contacting the operation surface 105.

[0068] Electronic device 100 may be, for example, a tablet-type input device configured in shops, facilities, etc., and used by a large number of unspecified users, or the input section of an ATM (Automatic Teller Machine). Furthermore, electronic device 100 may also be a personal tablet computer, smartphone, game console, etc.

[0069] As an example, the display device 110 is a liquid crystal display, an organic EL (electroluminescence) display, etc. The display device 110 displays images of the operation unit 111 using a GUI (Graphical User Interface). As an example, the operation unit 111 is arranged in a matrix shape when viewed from above.

[0070] exist Figures 1 to 3 As an example, 30 operation units 111 arranged in a 5x6 matrix are shown. The 30 operation units 111 are labeled (1, 1) to (5, 6) (row, column). Regarding the 30 operation units 111 arranged in a matrix, the 5 rows extend in the X direction and are arranged parallel in the Y direction. The 6 columns extend in the Y direction and are arranged side-by-side in the X direction. Alternatively, the electronic device 100 may also include operation units displayed on the operation surface 105 by printing or the like, without excluding the display device 110.

[0071] The electrostatic sensor 120 is stacked on top of the display device 110, such as... Figure 4 As shown, there are a total of 30 sensor electrodes 121, with 6 arranged in the X direction and 5 arranged in the Y direction. These 30 sensor electrodes 121 are connected to a control device 130 via 30 wires 122. Figure 4 The diagram shows a single wire 122, but in reality, 30 sensor electrodes 121 are independently connected to the control device 130 via 30 separate wires 122. As an example, such an electrostatic sensor 120 can be a type of electrostatic sensor where a transparent conductive film such as ITO (Indium Tin Oxide) is formed on the surface of transparent glass and patterned as the sensor electrodes 121 and the wires 122. The electrostatic capacitance of the electrostatic sensor 120 is input to the control device 130.

[0072] Here, as an example, a structure is shown in which 30 sensor electrodes 121 are respectively configured to overlap with 30 operating units 111. The row and column relationship of the 30 sensor electrodes 121 is the same as that of the operating units 111. Therefore, the 30 sensor electrodes 121 are arranged in 5 rows and 6 columns, and are labeled (1, 1) to (5, 6) in the same (row, column) manner as the 30 operating units 111. The positions of the 30 sensor electrodes 121 are indicated by row numbers and column numbers.

[0073] Hereinafter, rows are designated as i, columns as j, and the positions of each sensor electrode 121 are represented by (i, j). As an example, rows i range from 1 to 5, and columns j range from 1 to 6. For example, the sensor electrode 121 in the first row is located at the end on the +Y direction side, and the sensor electrode 121 in the fifth row is located at the end on the -Y direction side. The sensor electrode 121 in the first column is located at the end on the -X direction side, and the sensor electrode 121 in the sixth column is located at the end on the +X direction side.

[0074] Furthermore, the row adjacent to row i in the -Y direction is row i+1, which is the next row. The row adjacent to row i in the +Y direction is row i-1, which is the previous row. Additionally, the column number j of the column closest to the -X direction is 1 (j=1). As an example, the column number j of the column closest to the +X direction is the largest column number. Here, the largest column number j is 6.

[0075] Hereinafter, without specifically distinguishing between sensor electrodes 121(i, j), they will be simply referred to as sensor electrodes 121. Furthermore, the sensor electrodes 121 and the operation unit 111 will be described in a one-to-one correspondence, but one operation unit 111 may correspond to multiple sensor electrodes 121.

[0076] The control device 130 is implemented by a computer including a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), input / output interfaces, and an internal bus.

[0077] The control device 130 includes a main control unit 131, an AD (Analog-to-Digital) converter 132, a counter 133, a decision unit 134, an action control unit 135, a display control unit 136, and a memory 137. The main control unit 131, AD converter 132, counter 133, decision unit 134, action control unit 135, and display control unit 136 represent the functions of the program executed by the control device 130 as function blocks. Furthermore, the memory 137 functionally represents the memory of the control device 130.

[0078] The main control unit 131 is a processing unit that oversees the processing of the control device 130, and performs processing other than that performed by the AD conversion unit 132, the counter 133, the decision unit 134, the motion control unit 135, and the display control unit 136. For example, the main control unit 131 scans 30 sensor electrodes 121.

[0079] The AD converter 132 converts the output of the electrostatic sensor 120 into a digital value. The output of the AD converter 132 is the detected value of the electrostatic capacitance between each sensor electrode 121 of the electrostatic sensor 120 and the surrounding conductor. The counter 133 counts and outputs the difference between the output of the AD converter 132 and a reference value. The difference value is the count value of the change in the output reference value. Hereinafter, it is denoted as the difference value ΔAD. The output of the AD converter 132 is the electrostatic capacitance between each sensor electrode 121 and the surrounding conductor. The reference value is the electrostatic capacitance between each sensor electrode 121 and the surrounding conductor when there is no finger around each sensor electrode 121. The difference value ΔAD is the electrostatic capacitance between each sensor electrode 121 and the finger.

[0080] Since the differential value ΔAD is obtained for each sensor electrode 121, 30 differential values ​​ΔAD are obtained from the output of the electrostatic sensor 120. The differential value obtained based on the electrostatic capacitance of the sensor electrode 121(i,j) is represented as differential value ΔAD(i,j). The AD conversion unit 132 converts the electrostatic capacitance of the sensor electrode 121(i,j) into a digital value, and the counter 133 counts the change in the output of the AD conversion unit 132 relative to the reference value, and outputs the differential value ΔAD(i,j) for the 30 sensor electrodes 121(i,j). In addition, unless otherwise specified, the differential value ΔAD(i,j) is simply labeled as differential value ΔAD.

[0081] The determination unit 134 determines the position of the fingertip FT, the position of the palm P, and the position where neither the fingertip FT nor the palm P is present, based on the differential value ΔAD output from the counter 133. In the electronic device 100 and the contactless input device 100A, the determination unit 134 determines the position of the tip of the fingertip FT as the position of the operation input performed by the user. The determination method performed by the determination unit 134 will be described later using a flowchart.

[0082] The motion control unit 135 controls the operation of the electronic device 100 based on the position of the operation input determined by the determination unit 134. The display control unit 136 controls the display of the display device 110 based on the position of the operation input determined by the determination unit 134. The memory 137 stores programs, data, etc., used by the main control unit 131, the determination unit 134, the motion control unit 135, and the display control unit 136 during processing. In addition, the memory 137 stores data indicating the number of rows and columns of the sensor electrodes 121.

[0083] Figure 5 This is a diagram illustrating an example of the distribution of the difference value ΔAD and its reciprocal in relation to the electrode surface of the electrostatic sensor 120 for the hand H. The electrode surface is the surface of the 30 sensor electrodes 121. The reciprocal is the reciprocal of the difference value ΔAD.

[0084] If Figure 5 As shown on the left, the fingertip FT and the palm P are close to the electrode surface, and Figure 5 Comparing the differential value ΔAD shown on the right side (where the fingertip FT and palm P are slightly further away from the electrode surface than on the left side), the differential value ΔAD is larger when the fingertip FT and palm P are closer to the electrode surface on the left side compared to when they are slightly further away on the right side. The differential value ΔAD is the change in electrostatic capacitance caused by the hand, detected by the electrostatic sensor 120. ΔAD is inversely proportional to the distance between the electrode surface and the fingertip FT and palm P. Furthermore, because it is inversely proportional to distance, even with the same hand posture, different distances between the electrode surface and the fingertip FT and palm P will result in different waveforms representing the distribution of the differential value ΔAD. Figure 5 In the middle, on either the left or right side, the fingertip FT of the index finger is extended.

[0085] In contrast, the waveform representing the distribution of the reciprocal is less affected by the difference in distance between the electrode surface and the fingertip FT and the palm P compared to the waveform representing the distribution of the difference value ΔAD, resulting in more similar waveforms. This is because the reciprocal of the difference value ΔAD is a function of the distance between the electrode surface and the fingertip FT and the palm P.

[0086] Figure 6This diagram illustrates an example of the distribution of the reciprocals of the length and width directions of the hand H. The length direction of hand H refers to the direction from the wrist, through the palm P, to the fingertips FT. The width direction of hand H refers to the direction orthogonal to the length direction of hand H when viewed from above, and is the direction towards the thumb and little finger.

[0087] exist Figure 6 In the diagram, the distribution on the left side of hand H (A) represents the reciprocal distribution in the length direction, the distribution on the upper right side of hand H (B) represents the reciprocal distribution in the width direction at the fingertip FT position, and the distribution on the lower right side of hand H (C) represents the reciprocal distribution in the width direction at the palm P position.

[0088] In the distribution of the reciprocal of the hand H along the length direction in distribution (A), the reciprocal distribution is a gentle curve in the interval where the hand H exists. However, as shown by arrow FT, the reciprocal changes drastically at the boundary between the portion where the fingertip FT exists and the portion without hand H that is further forward than the fingertip FT. Therefore, if the location of the drastic change in the reciprocal can be determined, the position of the fingertip FT in the length direction can be determined based on the distribution of the reciprocal.

[0089] Furthermore, in the width direction distribution of the reciprocal of the fingertip FT position in distribution (B), the reciprocal decreases in a V-shape only in the interval where the fingertip FT is located. Therefore, if the position of the V-shaped change in the reciprocal is determined, the position of the fingertip FT in the width direction can be determined based on the distribution of the reciprocal. A quadratic curve can be fitted to the curve with the V-shaped change in the reciprocal.

[0090] Furthermore, in the distribution of the reciprocal of the width direction at the position of the palm P in distribution (C), the reciprocal of the interval where the palm P is located is smaller than the two ends where the palm P is not located, and takes a smaller value throughout the interval wider than the fingertip FT width direction. Therefore, if the position where the smaller value is taken in the interval wider than the fingertip FT width direction is determined, the position of the palm P in the width direction can be determined based on the distribution of the reciprocal. In the curve corresponding to the shape of the palm P, a quadratic curve, which is flatter than the fingertip FT, and a circle can be fitted. It is assumed that there is a large difference in the quadratic coefficients between the quadratic curve fitted to the fingertip FT and the quadratic curve fitted to the palm P.

[0091] Figure 7 This is a graph illustrating the quadratic coefficients of the quadratic curves fitted to the fingertip FT and palm P. Figure 7 The upper side of the figure represents the hand H with the index finger extended from the front. The quadratic curve 10FT, represented by a dashed line, is fitted to the FT of the fingertip, and the quadratic curve 10P, represented by a solid line, is fitted to the P of the palm.

[0092] like Figure 7 As shown in the lower half, the quadratic curves 10FT and 10P are obtained by converting z = ax2 The quadratic curves were obtained by setting the quadratic coefficient 'a' to 1 (a = 1) and 8 (a = 8), respectively. Thus, by setting the quadratic coefficient 'a' to an appropriate value, the quadratic curves 10FT and 10P fitted to the fingertip FT and palm P can be obtained. The quadratic curves 10FT and 10P can be obtained through curve fitting.

[0093] Furthermore, because the widths of the fingertips (FT) and the palm (P) are significantly different, the coefficients 'a' of the quadratic curves fitted through curve fitting are also quite different. For example... Figure 7 As shown, as an example, the quadratic coefficient 'a' of the quadratic curve fitted to the fingertip FT is 8, while the quadratic coefficient 'a' of the quadratic curve fitted to the palm P is 1. Therefore, by finding the distribution of the reciprocal of the difference value ΔAD and obtaining the quadratic coefficient 'a' of the fitted quadratic curve through curve fitting, it is possible to distinguish between the fingertip FT and the palm P. If the position of the fingertip FT can be determined, non-contact operation input can be achieved.

[0094] The larger the quadratic coefficient 'a' of the conic section obtained by curve fitting the distribution of the reciprocal of the difference ΔAD, the sharper the conic section becomes, forming a V-shape. Here, the quadratic coefficient 'a' is calculated as the sharpness of the conic section, and the position of the fingertip FT is determined based on this sharpness. Sharpness refers to the degree to which the V-shape of the conic section is abrupt.

[0095] Next, use Figures 8 to 13 The flowchart illustrates the method for determining the position of the fingertip FT. Figures 8 to 13 This is a flowchart illustrating the process of determining the position of the fingertip FT. This process is performed by the decision unit 134. Figure 8 Indicates the main flow, Figures 9 to 13 They represent Figure 8 The process flow of subroutines S3 to S7 in the above steps. Furthermore, as an example, the following rules are illustrated: [e.g., ...] Figure 3 As shown, operation input is performed by covering the electronic device 100 with a hand H above the operation surface 105 from one side of the end edge extending in the X direction on the -Y direction side of the electronic device 100 toward the +Y direction side.

[0096] When processing begins, the determination unit 134 reads the number of rows and columns of the sensor electrodes 121 from the memory 137 (step S1). AllRows represents the number of rows of the sensor electrodes 121, and AllColumns represents the number of columns of the sensor electrodes 121. As an example, AllRows is 5 rows and AllColumns is 6 columns.

[0097] Next, the determination unit 134 obtains the difference values ​​ΔAD(1,1) to ΔAD(AllRows, AllColumns) for all sensor electrodes 121 (step S2). As an example, through the processing of step S2, 30 difference values ​​AD(1,1) to ΔAD(AllRows, AllColumns) for 30 sensor electrodes 121 are obtained.

[0098] Next, the determination unit 134 calls the subroutine "sub reciprocal transformation" to transform all difference values ​​ΔAD(1,1) to ΔAD(AllRows,AllColumns) into their reciprocals (step S3).

[0099] Next, the determination unit 134 calls the subroutine "sub minimum value determination" to determine the minimum value of the reciprocal in all rows and to process the process of finding the column representing the minimum value of the reciprocal (step S4).

[0100] Next, the decision unit 134 calls the subroutine "sub Exclude Row Determination" to determine excluded rows (step S5). Excluded rows refer to rows where there is no hand H. The process involves determining and excluding rows where there is no hand, thereby filtering out rows where there is a hand.

[0101] Next, the determination unit 134 calls the subroutine "sub Sharpness Calculation" to calculate the sharpness of the rows containing hands (step S6).

[0102] Next, the determination unit 134 calls the subroutine "sub Fingertip Determination" to determine the line of the fingertip FT based on the sharpness calculated for all lines of the hand present in step S6 (step S7).

[0103] Finally, the determination unit 134 outputs coordinates representing the position of the tip of the fingertip FT based on the row of the fingertip determined in step S7 (step S8). Here, row represents the row number where the fingertip FT is located. In addition, column(i) represents the column number that is the smallest in the i-th row, so column(row) represents the column number that is the smallest in the row row.

[0104] Next, use Figure 9 , based on Figure 8 The reciprocal transformation process performed by the subroutine "sub reciprocal transformation" in step S3 will be explained.

[0105] The decision unit 134 performs the following loop process: while selecting row i one by one from i=1 to AllRows, it calculates the reciprocal of the difference value ΔAD(i,j) with respect to all columns j included in all rows i (steps S11 to S15). i=1, AllRows, 1 means that the reciprocal calculation is performed while selecting row by row from row number i=1 to AllRows.

[0106] The decision unit 134 performs the following loop processing for the selected row i: while selecting column j one by one from j=1 to AllColumns, it calculates the reciprocal of the difference value ΔAD(i,j) of all columns (steps S12 to S14). j=1, AllColumns, 1 means that the reciprocal calculation is performed column by column from column number i=1 to AllColumns.

[0107] For the selected row i, the determination unit 134 sequentially selects column j to calculate the reciprocal (i, j) of the difference value ΔAD(i, j) (step S13). The determination unit 134 stores the calculation result in step S13 as sorted data with row number i and column number j as elements in memory 137. The reciprocal (i, j) of the difference value ΔAD(i, j) is obtained by Reciprocal(i, j) = 1 / ΔAD(i, j).

[0108] The determination unit 134 performs the loop processing of steps S12 to S14 for the selected row i until the reciprocal of the difference value ΔAD(i,j) of all columns j is calculated (step S14). The determination unit 134 repeatedly performs the processing of steps S12 to S14 for the selected row i, thereby calculating the reciprocal of the difference value ΔAD(i,j) of all columns j in the selected row i.

[0109] The determination unit 134 performs the loop processing of steps S11 to S15 until it calculates the reciprocal of the difference value ΔAD(i,j) for all columns j included in all rows i. The determination unit 134 repeatedly performs the processing of steps S11 to S15, selecting all rows one by one while calculating the reciprocal of the difference value ΔAD for all columns included in each row.

[0110] Next, use Figure 10 , based on Figure 8 The subroutine "sub minimum value determination" in step S4 will be explained to determine the minimum value of the reciprocal of all rows.

[0111] The determination unit 134 performs the following cyclic processing: while selecting row i one by one from i=1 to AllRows, it determines the minimum value of the reciprocal of all columns j included in all rows i and gives the sensor electrode 121(i,j) that has the minimum value (steps S21 to S28). i=1, AllRows, 1 means that while selecting row by row from row number i=1 to AllRows, the sensor electrode 121(i,j) is determined.

[0112] The determination unit 134 sets the initial value of the minimum value of the reciprocal of the selected row i, Minimum(i), to be close to the determination threshold (step S22). By repeating the processing of steps S23 to S27, the minimum value of the reciprocal of the selected row i, Minimum(i), becomes the minimum value of the reciprocal of all columns j included in the selected row i. In addition, the close determination threshold is the threshold for determining whether the fingertip FT is close to the operation surface 105 for operation input. If the reciprocal (i,j) of the difference value ΔAD(i,j) in row i is below the close determination threshold in all columns j, the minimum value of the reciprocal of the row i, Minimum(i), is substituted into the close determination threshold. The row i that has been substituted into the close determination threshold is determined as an excluded row as described later. In addition, the initial value of the minimum value of the reciprocal, Minimum(i), only needs to be set to a value above the close determination threshold. For example, it can also be set to the maximum value that can be substituted into the minimum value, Minimum(i), under the constraints of the programming language. In this case, the minimum value of the reciprocal in row i is always substituted into Minimum(i).

[0113] In the selected row i, the determination unit 134 performs a cyclic process (steps S23 to S27) to determine the minimum value of the reciprocal of all columns j and to give the sensor electrode 121(i, j) with the minimum value. j = 1, AllColumns, 1 means that the minimum value and the sensor electrode 121(i, j) are determined column by column from column j = 1 to AllColumns.

[0114] The determination unit 134 determines whether the reciprocal Reciprocal(i,j) is less than the minimum value Minimum(i) (step S24).

[0115] When the determination unit 134 determines that the reciprocal (i, j) is less than the minimum value (i) (step S24: yes), the minimum value (i) is replaced with the reciprocal (i, j) (step S25). This is to update the minimum value (i) in the i-th row. The determination unit 134 stores the updated minimum value (i) in step S25 as permutation data with row number i as the element in the memory 137.

[0116] The determination unit 134 substitutes j into the column (i) that gives the minimum value Minimum(i) in the i-th row (step S26). That is, Column(i) = j. Column(i) represents the column number that is the smallest in the i-th row. For example, in the 2nd row, if the 3rd column is the smallest, then Reciprocal(2,3) < Minimum(2) is true. Therefore, Reciprocal(2,4) < Minimum(2), Reciprocal(2,5) < Minimum(2), and Reciprocal(2,6) < Minimum(2) are not true. Therefore, Column(2) = 3. The determination unit 134 stores the value obtained in step S26 in the memory 137.

[0117] For the selected row i, the determination unit 134 performs the cyclic processing of steps S23 to S27 in order to determine the minimum value of the reciprocal and the sensor electrode 121(i,j) that gives the minimum value.

[0118] The determination unit 134 performs the loop processing of steps S21 to S28 until the minimum value of the reciprocal of all rows is determined and the sensor electrode 121(i,j) that gives the minimum value is determined. Thus, the minimum value of the reciprocal of all rows and the sensor electrode 121(i,j) that gives the minimum value are determined.

[0119] Next, use Figure 11 , based on Figure 8 The process of determining the excluded row in the subroutine "sub Exclude Row Determination" of step S5 will be explained.

[0120] The decision unit 134 performs a loop process for all rows i from i=1 to AllRows-1, where if the minimum value of the reciprocal of row i is more than twice the minimum value of the reciprocal of row i+1 of the next row, then row i is excluded (steps S31 to S34).

[0121] Here, the next row i+1 is the row adjacent to a row i in the -Y direction. i=1, AllRows-1, where 1 means that the excluded rows are determined while selecting row by row from row number i=1 to AllRows-1. The process is repeated up to row number AllRows-1 because there is no next row for row AllRows.

[0122] In the process of identifying excluded rows, if the minimum value of the reciprocal of row i is more than twice the minimum value of the reciprocal of row i+1 of the next row, then row i is excluded to prevent the space near the fingertip FT from being misidentified as a finger. Even if there is no finger at the position opposite to sensor electrode 121(i,j), if a finger is present near sensor electrode 121(i,j), the electrostatic capacitance increases. Therefore, sometimes the space is misidentified as a finger simply by comparing the reciprocal of the electrostatic capacitance with a threshold. If the finger is not opposite to sensor electrode 121, but a finger is present near sensor electrode 121, the electrostatic capacitance value of sensor electrode 121(i,j) is significantly different from the electrostatic capacitance value of the adjacent sensor electrode 121(i+1,j). The minimum value of the reciprocal of the row overlapping the tip of the fingertip FT is small, and since the row above the row overlapping the tip of the fingertip FT does not overlap with the tip of the fingertip FT, the minimum value of the reciprocal becomes large. In rows that overlap with the front of the fingertip FT and the row preceding it, the minimum reciprocal value is significantly different. Here, as an example, we capture the position where the minimum reciprocal value is more than twice the minimum reciprocal value of the fingertip FT as the position of the row preceding the front of the fingertip FT. If the minimum reciprocal value of row i is more than twice the minimum reciprocal value of the next row i+1, then row i is excluded. In this case, row i+1 overlaps with the front of the fingertip FT, while row i does not, and is therefore excluded.

[0123] For the selected row i, the determination unit 134 determines whether the minimum value of the reciprocal in row i, Minimum(i), is more than twice the minimum value of the reciprocal in row i+1 of the next row, Minimum(i+1) (step S32).

[0124] If the determination unit 134 determines that the minimum value Minimum(i) is more than twice the minimum value Minimum(i+1) (S32: Yes), it substitutes "exclude" into Except1(i) (step S33A). The row i in which "exclude" is substituted into Except1(i) is a row that is not included in the sharpness calculation described later. The determination unit 134 stores Except1(i) as permutation data with row number i as the element in memory 137.

[0125] On the other hand, if the determination unit 134 determines that the minimum value Minimum(i) is not more than twice the minimum value Minimum(i+1) (S32: No), then it substitutes the "object" into Except1(i) (step S33B). The row i in which the "object" is substituted into Except1(i) is the row that can be the object of the sharpness calculation described later. The determination unit 134 stores Except1(i) as permutation data with row number i as the element in the memory 137.

[0126] The determination unit 134 performs the loop processing of steps S31 to S34 for all rows i until the processing ends when the minimum value of the reciprocal of row i is more than twice the minimum value of the reciprocal of the next row i+1, and then stores row i as an excluded row.

[0127] Next, the determination unit 134 sets the bottom row, AllRows, as the object row (step S35). That is, it becomes Except1(AllRows) = "object". Since the first bottom row, AllRows, does not have a next row, it is set as an object here.

[0128] Next, the decision unit 134 performs a loop process for all rows i from i=2 to AllRows, where if the minimum value of the reciprocal in row i is more than twice the minimum value of the reciprocal in row i-1 of the previous row, then row i is excluded (steps S36 to S39).

[0129] Here, row i-1 above is the row adjacent to row i in the +Y direction. i=2, AllRows, 1 means that the excluded rows are determined by selecting rows one by one from row number i=2 to AllRows. Row number i=1 is excluded because there is no row above the top row.

[0130] In the process of determining which rows to exclude, row i is excluded if the minimum value of the reciprocal in row i is more than twice the minimum value of the reciprocal in row i-1 of the previous row. This is to prevent the space near the fingertip FT from being misidentified as a finger. The reason for excluding row i if it is more than twice is that if there is a fingertip FT in both row i and row i-1 of the previous row, the minimum value of the reciprocal in row i will not be more than twice the minimum value of the reciprocal in row i-1 of the previous row. Furthermore, this is consistent with the loop processing in steps S31 to S34.

[0131] For the selected row i, the determination unit 134 determines whether the minimum value of the reciprocal in row i, Minimum(i), is more than twice the minimum value of the reciprocal in row i-1 of the previous row, Minimum(i-1) (step S37).

[0132] If the determination unit 134 determines that the minimum value Minimum(i) is more than twice the minimum value Minimum(i-1) (S37: Yes), it substitutes "exclude" into Except2(i) (step S38A). The row i in which "exclude" is substituted into Except2(i) is a row that is not included in the sharpness calculation described later. The determination unit 134 stores Except2(i) as permutation data with row number i as the element in memory 137.

[0133] On the other hand, if the determination unit 134 determines that the minimum value Minimum(i) is not more than twice the minimum value Minimum(i-1) (S37: No), then the "object" is substituted into Except2(i) (step S38B). The row i in Except2(i) in which the "object" is substituted is the row that can be the object of the sharpness calculation described later. The determination unit 134 stores Except2(i) as arrangement data with row number i as the element in memory 137.

[0134] The determination unit 134 performs the loop processing of steps S36 to S39 for all rows i until the processing ends when the minimum value of the reciprocal in row i is more than twice the minimum value of the reciprocal in row i-1 of the previous row, and then stores row i as an excluded row.

[0135] Next, the determination unit 134 sets the top row, i.e., i=1, as the object row (step S40). That is, it becomes Except2(1) = "object". The top row does not have a previous row, so it is set as an object here.

[0136] Next, the determination unit 134 performs a loop process for all rows i from i=1 to AllRows, where if the minimum value of the reciprocal of row i is close to or above the determination threshold, row i is excluded (steps S41 to S44).

[0137] i = 1, AllRows. 1 means that rows are selected one by one from row number i = 1 to AllRows while determining the excluded rows. Furthermore, if the minimum value of the reciprocal in row i is close to or above the decision threshold, row i is excluded to determine whether a fingertip FT exists in row i.

[0138] For the selected row i, the determination unit 134 determines whether the minimum value of the reciprocal of row i, Minimum(i), is close to or above the determination threshold (step S42).

[0139] If the determination unit 134 determines that the minimum value Minimum(i) is close to or above the determination threshold (S42: Yes), it substitutes "Exclude" into Except3(i) (step S43A). If it is less than the close to the determination threshold, there is no conductor near the sensor electrode 121(i,j). The row i in which "Exclude" is substituted into Except3(i) is a row that is not included in the sharpness calculation described later. The determination unit 134 stores Except3(i) as arranged data with row number i as an element in the memory 137. In this embodiment, when the minimum value of the reciprocal in row i is close to or above the determination threshold, Minimum(i) is set to close to the determination threshold. Therefore, the row i in which the minimum value of the reciprocal is close to or above the determination threshold is substituted with "Exclude" into Except3(i).

[0140] On the other hand, if the determination unit 134 determines that the value is not close to or above the determination threshold (S42: No), it substitutes the "object" into Except3(i) (step S43B). The row i in Except3(i) in which the "object" is substituted is the row that can be the object of the sharpness calculation described later. The determination unit 134 stores Except3(i) as arrangement data with row number i as the element in the memory 137.

[0141] The determination unit 134 performs the cyclic processing of steps S41 to S44 for all rows i until the processing of excluding row i ends when the minimum value of the reciprocal in row i is close to or above the determination threshold.

[0142] Next, the decision unit 134 performs the following loop process: while selecting row i one by one from i=1 to AllRows, it determines the excluded rows (steps S45 to S48). i=1, AllRows, 1 means that from i=1 to AllRows, the row selected one by one is selected in order to determine the excluded rows.

[0143] For the selected row i, the determination unit 134 determines whether Except1(i) = "object", Except2(i) = "object", and Except3(i) = "object" (step S46).

[0144] If the determination unit 134 determines "yes" in step S46, it substitutes the "object" into Except(i) (step S47A). The row i in which the "object" is substituted into Except(i) is the row that becomes the object of the sharpness calculation described later. The row i in which the "object" is substituted into Except(i) contains sensor electrodes 121(i,j) opposite to the hand. The determination unit 134 stores Except(i) as arranged data with row number i as the element in memory 137. When the processing of step S47A ends, the determination unit 134 proceeds to step S48.

[0145] On the other hand, if at least one of Except1(i), Except2(i), and Except3(i) is "excluded", then the determination unit 134 determines "no" in step S46. If the determination is "no" in step S46, then "excluded" is substituted into Except(i) (step S47B). The row i in which "excluded" is substituted into Except(i) is a row that is not an object of the sharpness calculation described later. The row i in which "excluded" is substituted into Except(i) does not have a sensor electrode 121(i,j) opposite to the hand. In other words, the sensor electrode 121(i,j) in row i in which "excluded" is substituted into Except(i) is opposite to space. The determination unit 134 stores Except(i) as arrangement data with row number i as an element in the memory 137.

[0146] The determination unit 134 performs the cyclic processing of steps S45 to S48 on all rows i until the processing of the excluded rows is completed. Through the above, the excluded row i is determined from all rows i.

[0147] Next, use Figure 12 , for calculation based Figure 8 The sharpness processing performed in the subroutine "sub-sharpness calculation" of step S6 will be explained. Figure 12 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation".

[0148] The determination unit 134 performs a loop process (steps S51 to S57) that selects row i one by one from i=1 to AllRows while calculating the sharpness. i=1, AllRows, 1 means that the sharpness is calculated while selecting row by row from i=1 to AllRows.

[0149] For the selected row i, the determination unit 134 determines whether it is an object with Except(i) = "object" (step S52). If it is not an object, the sharpness is not calculated.

[0150] If the determination unit 134 determines that Except(i) = "object" (S52: yes), it determines whether the column (i) that gives the minimum value Minimum(i) in the i-th row is the first column (step S53). That is, for the i-th row, it determines whether Column(i) = 1. This is to determine whether the minimum value Minimum(i) can be obtained in the first column (the column at the end on the -X direction side) in the i-th row.

[0151] If the determination unit 134 determines that Column(i) is not 1 (S53: No), it then determines whether Column(i) is equal to AllColumns (step S54). That is, it determines whether Column(i) is equal to AllColumns for the i-th row. This is to determine whether the minimum value Minimum(i) can be obtained in the column at the end of the +X direction side represented by AllColumns in the i-th row.

[0152] If the determination unit 134 determines that Column(i) is not equal to AllColumns (S54: No), then Column(i) is substituted into j (step S55A). That is, if Column(i) represents something other than the end, then Column(i) is substituted into j. Column(i) represents the column in the i-th row that represents the minimum value Minimum(i) (see step S26).

[0153] The decision unit 134 calculates the sharpness Apex(i) (step S56). The sharpness Apex(i) is calculated according to the following formula.

[0154] Apex(i)=Reciprocal(i,j-1)-2Reciprocal(i,j)+Reciprocal(i,j+1)

[0155] If the determination unit 134 determines in step S52 that Except(i) is not "object" (S52: No), it sets the sharpness Apex(i) to zero (step S52A). That is, the sharpness Apex(i) becomes 0. Since the row is not an object of sharpness calculation, the sharpness Apex(i) is set to zero. As will be described later, the sharpness Apex(i) is used when determining the row where the fingertip is located. By setting a specific value (zero) in the sharpness Apex(i) of the row that is not an object of sharpness calculation, the same steps can be used to process the rows that are objects of sharpness calculation and the rows that are not objects of sharpness calculation. As will be described later, in this embodiment, if sharpness is calculated, a positive value is calculated. As will be described later, the row with the highest sharpness is determined to be the row with the fingertip. Therefore, setting the sharpness Apex(i) to zero is equivalent to setting row i as the row that does not have the fingertip. If the decision unit 134 terminates the processing of step S52A, it proceeds to step S57.

[0156] Furthermore, if the determination unit 134 determines in step S53 that Column(i) = 1 (S53: Yes), it sets j = 2 (step S53A). This is because, since the column Column(i) that gives the minimum value Minimum(i) in the i-th row is the column at the end of the -X direction side (column 1), the column j, which is the middle of the three columns used for sharpness calculation, is set as column 2, and the sharpness is calculated using the three reciprocals of columns 1 to 3. When the processing of step S53A ends, the determination unit 134 proceeds to step S56 to calculate the sharpness.

[0157] Furthermore, if the determination unit 134 determines in step S54 that Column(i) = AllColumns (S54: Yes), it sets j = AllColumns-1 (step S55B). Since the column Column(i) that gives the minimum value Minimum(i) in the i-th row is the end column on the +X direction side (the sixth column represented by AllColumns), the middle column j of the three columns used for sharpness calculation is set to AllColumns-1 (the 5th column), and the sharpness is calculated using the three reciprocals from the 4th to the 6th columns. If the determination unit 134 ends the processing in step S55B, it proceeds to step S56 to calculate the sharpness.

[0158] The determination unit 134 performs the loop processing of steps S51 to S57 for all rows i until the sharpness calculation is completed.

[0159] Next, use Figure 13 , based on Figure 8The process of determining the position of the fingertip FT in the subroutine "sub-fingertip determination" of step S7 will be explained. The position of the fingertip FT is determined as the position of column j represented by Column(i) in row i, which includes the maximum sharpness MaxApex representing the maximum sharpness. Column(i) represents the column with the smallest reciprocal calculated for each row (see step S26).

[0160] The determination unit 134 sets the initial value of the maximum sharpness MaxApex to zero (step S61).

[0161] The decision unit 134 performs a loop process (steps S62 to S66) to determine the position of the fingertip FT by selecting row i one by one from i=1 to AllRows. i=1, AllRows, 1 means that the position of the fingertip FT is determined by selecting row i one by one from row number i=1 to AllRows.

[0162] For the selected row i, the determination unit 134 determines whether the sharpness Apex(i) is greater than the maximum sharpness MaxApex (step S63). By repeatedly performing the process of step S63, the maximum sharpness MaxApex is updated, and finally the row i with the maximum sharpness MaxApex is determined.

[0163] When the determination unit 134 determines that the sharpness Apex(i) is greater than the maximum sharpness MaxApex (S63: Yes), it updates the maximum sharpness MaxApex to the sharpness Apex(i) (step S64).

[0164] The decision unit 134 substitutes the row i of the sharpness Apex(i) of the maximum sharpness MaxApex into the variable row. (Step S65).

[0165] The determination unit 134 performs cyclic processing of steps S61 to S66 for all rows i, thereby substituting the row number representing the maximum sharpness into row.

[0166] When the loop processing of steps S61 to S66 ends, the aforementioned process is performed. Figure 8 The main loop's S8 process: As mentioned above, the row number where the finger's tip is located is substituted into `row`. Furthermore, the column number that is the smallest in each row is substituted into `Column(i)`. Therefore, the output (row, Column(row)) is used as the coordinates of the finger's tip (step S8).

[0167] Next, use Figure 14 as well as Figure 15 A specific example is given from obtaining the difference value ΔAD to determining the position of the fingertip FT. Figure 14It is a graph representing the distribution of the difference ΔAD, the distribution of the reciprocal, and column j, which gives the minimum value of the reciprocal represented by Column(i), Minimum(i).

[0168] Figure 14 (A) is a graph representing the distribution of the differential values ​​ΔAD obtained from the 5 rows and 6 columns of sensor electrodes 121. For example... Figure 2 as well as Figure 3 As shown, operation inputs are applied to sensor electrodes 121 (2, 3) in the second row and third column.

[0169] Figure 14 (B) indicates that Figure 14 The difference value ΔAD shown in (A) is 1000 times the reciprocal of the difference value. Figure 14 (C) is a graph showing the relationship between the minimum value Minimum(i) in each row representing the value of 1000 times the reciprocal of ΔAD and the column number Column(i) of the electrode representing the minimum value Minimum(i). In the first row, 5, which is close to the decision threshold, is substituted into the minimum value Minimum(1). In the first row, since all values ​​of 1000 times the reciprocal of the difference ΔAD exceed the close decision threshold of 5, the close decision threshold (5), which is set as the initial value of the minimum value Minimum(1), is substituted as the minimum value. Furthermore, the column Column(i) of the minimum value in the first row is uncertain. Figure 14 In (C), it is recorded as "-". Furthermore, if the column (i) of the minimum value is not determined, the previous calculation result is maintained. In either case, the minimum value (Minimum(1)) is set to be close to the decision threshold (5), and therefore, it is not subject to sharpness calculation. Regardless of the value of Column(i) in row i that is not subject to sharpness calculation, it will not affect the processing result. Additionally, if the initial value of the minimum value (Minimum(i)) is set to the largest value that can be substituted into the minimum value (Minimum(i)), the actual minimum value is always substituted into the minimum value (Minimumu(i)). In this case, it will not be subject to sharpness calculation, so the subsequent processing is the same.

[0170] Figure 15 It is a graph representing the object for calculating sharpness, the minimum value Minimum(i), the result of the sharpness calculation, the maximum sharpness, and the coordinates. Figure 15(A) is a graph that shows whether each row is considered as a candidate for the position of the fingertip and becomes an object for calculating sharpness based on the size of the minimum value Minimum(i) and the comparison with the minimum values ​​Minimum(i-1) and Minimum(i+1) of the adjacent rows. The first row is not an object because "close to the decision threshold" is not true (FALSE).

[0171] Figure 15 (B) represents the value of 1000 times the reciprocal of the minimum value Minimum(i) and the difference ΔAD to its left and right in each row. Since the first row is the object of sharpness calculation, therefore... Figure 15 The (B) contains the character "-".

[0172] Figure 15 (C) represents the sharpness calculation results for each row. Here, as an example, sharpness is calculated using the quadratic coefficient of a quadratic function. Rows outside the area where sharpness is calculated (row 1) are set to 0.

[0173] Figure 15 (D) shows the maximum sharpness and the coordinates representing that maximum sharpness. Here, as an example, the sharpness is expressed using the quadratic coefficients of a quadratic function. Figure 15 In (C), the maximum value is 0.73, therefore the largest quadratic coefficient is 0.73. The largest quadratic coefficient (0.73) is recorded in Figure 15 The second row of (C) is therefore the row with the largest quadratic coefficient. The column with the minimum value in the second row, Column(2), is based on... Figure 14 (C) is the 3rd column. Therefore, the 3rd column of the 2nd row refers to the position of the tip.

[0174] As described above, the position of the fingertip FT can be determined. Therefore, a non-contact input device 100A can be provided that can accurately determine the position of the fingertip FT located away from the sensor electrode 121. That is, a non-contact input device 100A can be provided that can determine whether a non-contact operation has occurred and the position of the operation.

[0175] <Handling of Sharpness Calculation in the First Variation>

[0176] Figure 16 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the first variant. Figure 16 The processing shown makes the processing in step S56 similar to... Figure 12 The processing in step S56 shown is different. Here, regarding the difference between... Figure 12 The differences in the processing shown are explained.

[0177] exist Figure 16In the process shown, the determination unit 134 calculates the curvature of the circle passing through the next 3 points as the sharpness Apex(i) (step S56). The 3 points are represented by (j-1, Reciprocal(i, j-1)), (j, Reciprocal(i, j)), and (j+1, Reciprocal(i, j+1)).

[0178] Here, in the xz coordinate system where column j is set as the x-axis and the reciprocal Reciprocal as the z-axis, j-1, j, and j+1 are set as x1, x2, and x3, and Reciprocal(i, j-1), Reciprocal(i, j), and Reciprocal(i, j+1) are set as z1, z2, and z3. This state is as follows: Figure 17 As shown. Figure 17 This is a graph showing the relationship between the xz coordinates and the fingertip FT.

[0179] The coordinates (xp, zp) of the center of the circle passing through the three points are represented by the following equations (1) and (2).

[0180] [Mathematical Expression 1]

[0181]

[0182] [Mathematical Expression 2]

[0183]

[0184] Furthermore, when using the coordinates (xp, zp) of the center of the circle passing through the three points, the radius r of the circle can be obtained by the following equation (3).

[0185] [Mathematical Expression 3]

[0186]

[0187] The decision unit 134 calculates the sharpness Apex(i) as the curvature (the reciprocal of the radius, 1 / r). That is, the sharpness Apex(i) = 1 / r.

[0188] <Handling of Sharpness Calculation in the Second Variation>

[0189] Figure 18 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the second variation. Figure 18 The processing shown makes the processing in step S56 similar to... Figure 12 The processing in step S56 shown is different. Here, for... Figure 12 The differences in the processing shown are explained.

[0190] exist Figure 18In the process shown, the decision unit 134 uses 5 adjacent points in row i to obtain a quadratic curve that approximates the 5 points by curve fitting based on the least squares method, and calculates the quadratic coefficient of the curve as the sharpness Apex(i) (step S56).

[0191] The five adjacent points in row i are (j-2, Reciprocal(i, j-2)), (j-1, Reciprocal(i, j-1)), (j, Reciprocal(i, j)), (j+1, Reciprocal(i, j+1)), and (j+2, Reciprocal(i, j+2)).

[0192] <Handling of Sharpness Calculation in the Third Variation>

[0193] Figure 19 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the third variation. Figure 19 The processing shown makes the processing in step S56 similar to... Figure 12 The processing in step S56 shown is different. Here, for... Figure 12 The differences in the processing shown are explained.

[0194] exist Figure 19 In the process shown, the determination unit 134 uses 5 adjacent points in row i, and through curve fitting, uses the least squares method to find the circumference that approximates the 5 points, and calculates the curvature of the curve as the sharpness Apex(i) (step S56).

[0195] The five adjacent points in row i are (j-2, Reciprocal(i, j-2)), (j-1, Reciprocal(i, j-1)), (j, Reciprocal(i, j)), (j+1, Reciprocal(i, j+1)), and (j+2, Reciprocal(i, j+2)).

[0196] <Determining the treatment of the fingertip in the fourth variation>

[0197] Figure 20 This is a flowchart illustrating the fingertip determination process performed by the subroutine "sub Fingertip Determination" based on the fourth variant. Figure 20 The processing shown can replace Figure 13 The process is executed as shown.

[0198] The decision unit 134 performs the following loop process: while selecting row i one by one from i=1 to AllRows, it determines whether it is a finger, palm P, or space (steps S71 to S74). i=1, AllRows, 1 means that while selecting row by row from i=1 to AllRows, it determines whether it is a finger, palm P, or space.

[0199] The determination unit 134 determines whether the sharpness Apex(i) calculated in step S6 is above the palm threshold (step S72). The palm threshold is the value that distinguishes whether the sharpness Apex(i) is the sharpness of the finger or the sharpness of the palm P, and is the minimum value in the case of fingertip FT.

[0200] When the determination unit 134 determines that the sharpness Apex(i) is above the palm threshold (S72: Yes), it determines that Palm(i) is a finger (step S73A).

[0201] If the determination unit 134 determines in step S72 that the sharpness Apex(i) is not above the palm threshold (S72: No), it determines whether the sharpness Apex(i) is a positive value (step S72A). This is to determine whether the palm P exists or does not exist in space.

[0202] When the determination unit 134 determines that the sharpness Apex(i) is positive (S72A: Yes), it determines that Palm(i) is a palm (step S73B).

[0203] On the other hand, when the determination unit 134 determines in step S72A that the sharpness Apex(i) is not a positive value (S72A: No), it determines that Palm(i) is space (step S73C). Figure 12 In step S52A, in the case of space, 0 is input to Apex(i).

[0204] The determination unit 134 performs the loop processing of steps S71 to S74 for all rows i, thereby substituting the row number representing the palm P into Palm(i).

[0205] The determination unit 134 performs the following loop processing: while selecting row i one by one from i = AllRows-1 to row 1, it determines the fingers emerging from the lower palm P (steps S75 to S77). i = AllRows-1, 1, -1 means that while selecting row by row from i = AllRows-1 to row 1, it determines the fingers emerging from the lower palm P. Furthermore, "finger emerging from the lower palm P" means that the palm P is located on the -Y direction side, and the fingers are on the +Y direction side.

[0206] The determination unit 134 determines whether Palm(i) is a finger and Palm(i+1) is a palm P (step S76). This is a process of determining whether there is a finger in the i-th row and a palm P in the i+1-th row on the -Y direction side.

[0207] If the determination unit 134 determines that Palm(i) is a finger and Palm(i+1) is a palm P (S76: Yes), the process proceeds to step S78. On the other hand, if there is no line i that satisfies Palm(i) as a finger and Palm(i+1) as a palm P, the determination unit 134 ends the loop processing of "determining the finger coming out from the lower palm" (S75 to S77) and the process proceeds to step S83.

[0208] The determination unit 134 performs cyclic processing of steps S75 to S77 for all rows i, thereby determining whether it is a finger coming out from the lower palm P.

[0209] The determination unit 134 performs a loop process (steps S78 to S80) that selects row i one by one from i = AllRows-1 to row 2 while determining the fingertip in row i. i = AllRows-1, 2, -1 means that while selecting row by row from i = AllRows-1 to row 2, the determination of the finger coming out from the lower palm P is performed.

[0210] The determination unit 134 determines whether Palm(i) is a finger and Palm(i-1) is space (step S79). This is a process of determining whether there is a finger in the i-th row and space in the (i-1)-th row on the +Y direction side.

[0211] When the determination unit 134 determines that Palm(i) is a finger and Palm(i-1) is space (S79: Yes), the process proceeds to step S82. On the other hand, if there is no row i that satisfies Palm(i) as a finger and Palm(i-1) as space, the determination unit 134 ends the loop processing of "determining fingertip" (S78 to S80) and the process proceeds to step S81.

[0212] In step S81, the determination unit 134 substitutes 1 into i. If a finger extending from the palm P reaches the end of the electrostatic sensor 120, it is considered that a fingertip FT exists at the end of the electrostatic sensor 120. In other words, if there is no space on the +Y direction side, it is considered that the fingertip FT is located in the first row. If the determination unit 134 terminates the processing in step S81, it proceeds to step S82.

[0213] In step S82, which follows step S81, the determination unit 134 substitutes the i-th row determined in step S81 into the variable row (step S82). That is, row = 1. The fingertip FT is located in the first row.

[0214] When the processing of step S82 ends, the determination unit 134 terminates. Figure 20 The subroutine “sub fingertip determination” shown in the diagram determines the position of the fingertip (end), and performs the aforementioned main loop S8 processing.

[0215] Furthermore, in step S79, if the determination unit 134 determines that Palm(i) is a finger and Palm(i-1) is space (S79: Yes), it proceeds to step S82. In this case, the i-th row where Palm(i) is a finger and Palm(i-1) is space (S79: Yes) is substituted into the variable row (step S82). The fingertip FT is located in the i-th row where Palm(i) is a finger and Palm(i-1) is space (S79: Yes) was determined in step S79.

[0216] When the processing of step S82 ends, the determination unit 134 terminates. Figure 20 The subroutine "sub Fingertip Determination" shown handles the determination of the fingertip's position (end).

[0217] In step S83, the determination unit 134 performs a cyclic process (steps S83-S85) that selects row i one by one from i=2 to AllRows while determining the fingers emerging from the upper palm P. i=2, AllRows, 1 means that the determination of the fingers emerging from the upper palm P is performed while selecting row by row from i=2 to AllRows. Furthermore, a finger emerging from the upper palm P refers to a finger in the -Y direction when the palm P is located on the +Y side.

[0218] The determination unit 134 determines whether Palm(i) is a finger and Palm(i-1) is a palm P (step S84). This is the process of determining whether there is a finger in the i-th row and a palm P in the (i-1)-th row on the +Y direction side.

[0219] When the determination unit 134 determines that Palm(i) is a finger and Palm(i-1) is the palm P (S84: Yes), the process proceeds to step S86. On the other hand, if there is no line i that satisfies Palm(i) as a finger and Palm(i-1) as the palm P, the determination unit 134 ends the loop processing of "determining the finger that comes out from the upper palm" (steps S83 to S85) and proceeds to step S90. If the palm P is located further outward than the electrostatic sensor 120, the process proceeds to step S90.

[0220] The determination unit 134 performs cyclic processing of steps S83 to S85 for all rows i, thereby determining whether it is a finger coming out of the upper palm P.

[0221] The determination unit 134 performs a loop process (steps S86 to S89) that selects row i one by one from i=2 to AllRows while determining the fingertip in row i. i=2, AllRows, 1 means that while selecting row i one by one from row i=2 to AllRows, the determination of the finger coming out from the lower palm P is performed.

[0222] The determination unit 134 determines whether Palm(i) is a finger and Palm(i+1) is space (step S87). This is a process of determining whether there is a finger in the i-th row and space in the i+1-th row on the -Y direction side.

[0223] In step S87, when the determination unit 134 determines that Palm(i) is a finger and Palm(i+1) is space (S87: Yes), the process proceeds to step S82. In this case, the determination unit 134 substitutes the i-th row where Palm(i) is a finger and Palm(i+1) is space (S87: Yes) into the variable row (step S82). The fingertip FT is located in the i-th row where Palm(i) is a finger and Palm(i+1) is space (S87: Yes) determined in step S87.

[0224] On the other hand, if there is no row i that satisfies Palm(i) as a finger and Palm(i+1) as a space, then the determination unit 134 ends the loop processing of "determining the fingertip" and the process proceeds to step S89.

[0225] The determination unit 134 substitutes Allrows into i (step S89). If a finger extending from the palm P reaches the end of the electrostatic sensor 120, it is considered that there is a fingertip FT at the end of the electrostatic sensor 120. In other words, if there is no space on the -Y direction side, it is considered that the fingertip FT is located in the row of Allrows at the end of the electrostatic sensor 120.

[0226] When the palm P is located outside the electrostatic sensor 120, the determination unit 134 sets the initial value of the maximum sharpness MaxApex to zero (step S90).

[0227] The decision unit 134 selects row i one by one from i=1 to AllRows while performing a loop process of "finger tip position determination" (steps S91 to S95). i=1, AllRows, 1 means that the position of the fingertip FT is determined while selecting row by row from i=1 to AllRows.

[0228] For the selected row i, the determination unit 134 determines whether the sharpness Apex(i) is greater than the maximum sharpness MaxApex (step S92). By repeatedly performing the processing steps S91 to S95, the maximum sharpness MaxApex is updated, and finally the row i with the maximum sharpness MaxApex is determined.

[0229] When the determination unit 134 determines that the sharpness Apex(i) is greater than the maximum sharpness MaxApex (S92: Yes), it updates the maximum sharpness MaxApex to the sharpness Apex(i) (step S93).

[0230] The decision unit 134 substitutes the row i of the sharpness Apex(i) of the maximum sharpness MaxApex into the variable row. (Step S94).

[0231] The determination unit 134 performs cyclic processing of steps S91 to S95 on all rows i to substitute the row number representing the maximum sharpness into row (step S95).

[0232] When the determination unit 134 finishes the loop processing of steps S91 to S95, it performs the aforementioned processing of the main loop S8.

[0233] <Determining the position of the fingertip FT in the fifth variation>

[0234] Next, use Figures 21 to 23 The flowchart illustrates the method for determining the position of the fingertip FT in the fifth variation. Figures 21 to 23 This is a flowchart illustrating the process of determining the position of the fingertip FT in the fifth variation. This process is performed by the decision unit 134. Figure 21 Indicates the main flow, Figure 22 as well as Figure 23 They represent Figure 21 The process flow of subroutines in steps S103 and S109. Furthermore, regarding... Figure 21 The subroutine processing in steps S104 to S108 is referenced. Figures 9 to 13 The explanations for "sub reciprocal transformation", "sub minimum value determination", "sub excluding row determination", "sub sharpness calculation", and "sub fingertip determination" are omitted here. Additionally, as an example, let's assume that it can be derived from... Figure 3 The following describes the situation where the electronic device 100 is operated with its -Y, +Y, -X, and +X directions all facing the operation surface 105, and the hand H is placed over the electronic device 100 to perform operation input.

[0235] When processing begins, the determination unit 134 reads the number of rows and columns of the sensor electrodes 121 from the memory 137 (step S101). TemporalAllRows represents the number of rows of the sensor electrodes 121, and TemporalAllColumns represents the number of columns of the sensor electrodes 121. As an example, TemporalAllRows has 5 rows and TemporalAllColumns has 6 columns.

[0236] Next, the determination unit 134 obtains the difference values ​​ΔAD(1,1) to ΔAD(AllRows, AllColumns) for all sensor electrodes 121 and inputs them into TemporalCapa(1,1) to TemporalCapa(AllRows, AllColumns) (step S102). Through the processing in step S102, as an example, 30 difference values ​​TemporalCapa(1,1) to TemporalCapa(AllRows, AllColumns) for 30 sensor electrodes 121 are obtained.

[0237] Next, the decision unit 134 calls the subroutine "sub Transformation". If a transformation is required, row i and column j are swapped, and TemporalCapa(i, j) is input to Capacitance(j, i). If a transformation is not required, the decision unit 134 inputs TemporalCapa(i, j) to Capacitance (step S103).

[0238] Next, the determination unit 134 calls the subroutine "sub reciprocal transformation" to transform all the difference values ​​ΔAD(1,1) to ΔAD(AllRows,AllColumns) into their reciprocals (step S104).

[0239] Next, the determination unit 134 calls the subroutine "sub minimum value determination" to determine the minimum value of the reciprocal in all rows and to process the process of finding the column representing the minimum value of the reciprocal (step S105).

[0240] Next, the determination unit 134 calls the subroutine "sub Exclude Row Determination" to determine excluded rows (step S106). Excluded rows refer to rows where there is no hand H. The process involves determining and excluding rows where there is no hand, thereby filtering out rows where there is a hand.

[0241] Next, the determination unit 134 calls the subroutine "sub Sharpness Calculation" to calculate the sharpness of the rows where hands are present (step S107).

[0242] Next, the determination unit 134 calls the subroutine "determination of the line of the fingertip" to determine the line of the fingertip FT based on the sharpness calculated for all lines of the hand in step S107 (step S108).

[0243] Next, the determination unit 134 calls the subroutine "sub cross-row return" to perform cross-row return processing (step S109).

[0244] Finally, the determination unit 134 outputs the coordinates representing the position of the tip of the fingertip FT (step S110). Here, row represents the row number where the fingertip FT is located. In addition, column(i) represents the column number that is the smallest in the i-th row, so column(row) represents the column number that is the smallest in the row row.

[0245] Next, use Figure 22 , based on Figure 21 The horizontal transformation process performed by the subroutine "subHorizontal Transformation" in step S103 will be explained.

[0246] The determination unit 134 obtains the X coordinate of the sensor electrode 121 with the largest electrostatic capacitance value (BigX(1), 1) and the Y coordinate of the sensor electrode 121 with the largest electrostatic capacitance value (BigY(1), 1) and the X coordinate of the sensor electrode 121 with the second largest electrostatic capacitance value (BigX(2), 2) and the Y coordinate of the sensor electrode 121 with the second largest electrostatic capacitance value (BigY(2), 2)) from the TemporalCapa(1, 1) to TemporalCapa(AllRows, AllColumns) obtained in step S102. The coordinates are defined as follows: BigX(3) = X-coordinate of sensor electrode 121 with the third largest electrostatic capacitance value; BigY(3) = Y-coordinate of sensor electrode 121 with the third largest electrostatic capacitance value; BigX(4) = X-coordinate of sensor electrode 121 with the fourth largest electrostatic capacitance value; BigY(4) = Y-coordinate of sensor electrode 121 with the fourth largest electrostatic capacitance value; BigX(5) = X-coordinate of sensor electrode 121 with the fifth largest electrostatic capacitance value; and BigY(5) = Y-coordinate of sensor electrode 121 with the fifth largest electrostatic capacitance value (step S111). Additionally, the X-coordinate is the column j number of sensor electrode 121, and the Y-coordinate is the row i number.

[0247] The decision unit 134 calculates the absolute value of the covariance of BigX(i) and BigY(i) and the absolute value of the variance of BigX(i) based on (BigX(1), BigY(1)), (BigX(2), BigY(2)), (BigX(3), BigY(3)), (BigX(4), BigY(4)), (BigX(5), BigY(5)) (step S112).

[0248] The determination unit 134 determines whether the absolute value of the covariance of BigX(i) and BigY(i) is the absolute value of the variance of BigX(i) (step S113).

[0249] If the absolute value of the covariance of BigX(i) and BigY(i) is less than or equal to the absolute value of the variance of BigX(i) (S113: Yes), then in order to change the rows and columns, TemporalAllColumns is substituted into AllRows, and TemporalAllRows is substituted into AllColumns (step S114A). That is, AllRows = TemporalAllColumns and AllColumns = TemporalAllRows.

[0250] The decision unit 134 performs a loop process that selects row i one by one from i=1 to AllRows while replacing all rows i (steps S115A to S119A). i=1, AllRows, 1 means that row i is selected one by one from row number i=1 to AllRows while replacing row i.

[0251] The decision unit 134 performs a loop process that selects column j one by one from j=1 to AllColumns while replacing all columns j (steps S116A to S118A). j=1, AllColumns, 1 means that the process of selecting column j one by one from column number j=1 to AllColumns while replacing column j.

[0252] The determination unit 134 substitutes TemporalCapa(i,j) into the electrostatic capacitance Capacitance(j,i) at position (j,i) (step S117A). As a result, the column and row are transformed.

[0253] The determination unit 134 performs the cyclical processing of steps S116A to S118A until all columns j are replaced (step S118A).

[0254] The decision unit 134 performs the loop processing of steps S115A to S119A until all rows i are replaced. The processing of the subroutine "sub Vertical Transformation" ends here.

[0255] In step S113, if the absolute value of the covariance of BigX(i) and BigY(i) is greater than the absolute value of the variance of BigX(i) (S113: No), the determination unit 134 substitutes TemporalAllRows into AllRows and substitutes TemporalAllColumns into AllColumns (step S114B). That is, AllRows = TemporalAllRows and AllColumns = TemporalAllColumns.

[0256] The decision unit 134 performs a cyclic process of selecting row i one by one from i=1 to AllRows while copying the difference value ΔAD of all rows i (steps S115B to S119B). i=1, AllRows, 1 means that the process of selecting row by row from row number i=1 to AllRows while copying is performed.

[0257] The determination unit 134 performs a cyclic process of selecting column j one by one from j=1 to AllColumns while copying the difference value ΔAD of all columns j (steps S116B to S118B). j=1, AllColumns, 1 means that the process of selecting and copying is performed one column by one from column number j=1 to AllColumns.

[0258] The determination unit 134 substitutes TemporalCapa(i,j) into the electrostatic capacitance Capacitance(i,j) at position (i,j) (step S117B). In this case, the column and row are not transformed.

[0259] The determination unit 134 performs the cyclic processing of steps S116B to S118B until all columns j are copied.

[0260] The decision unit 134 performs the loop processing of steps S115B to S119B until all rows i are copied. The processing of the subroutine "sub Horizontal Transformation" ends here.

[0261] Next, use Figure 23 , based on Figure 21 The processing performed by the subroutine "sub cross return" in step S109 will be explained.

[0262] The determination unit 134 determines whether the absolute value of the covariance of BigX(i) and BigY(i) is equal to the absolute value of the variance of BigX(i) (step S121). This is to determine whether to perform a horizontal / vertical return. The branch condition of step S121 is the same as that of step S113. In the case of a series of processes performed by changing the horizontal / vertical coordinates, the position of the fingertip is correctly output by changing the horizontal / vertical coordinates of the output coordinates.

[0263] When the determination unit 134 determines that "the absolute value of the covariance of BigX(i) and BigY(i)" is less than or equal to "the absolute value of the variance of BigX(i)" (S121: Yes), it replaces the values ​​of the variables row and column(Row). Therefore, after storing the value of variable row in variable j, column(Row) is substituted into variable row, and the value of variable j is substituted into variable column(Row) (step S122). If the determination unit 134 ends the processing of step S122, it ends the processing of the subroutine "sub cross-sectional return" (end).

[0264] When the determination unit 134 determines in step S121 that "the absolute value of the covariance of BigX(i) and BigY(i)" is greater than "the absolute value of the variance of BigX(i)" (S121: No), the processing of the subroutine "sub cross-sectional return" ends.

[0265] Next, use Figure 24 as well as Figure 25 This section provides a specific example illustrating the process from obtaining the difference value ΔAD to determining the position of the fingertip FT. For example... Figure 2 as well as Figure 3 As shown, operational inputs are applied to the 2x3 sensor electrodes 121 (2, 3). Furthermore, it is explained here that the inputs obtained during the "sub-reciprocal transformation" process in step S104 are... Figure 14 The result is the same as the difference value ΔAD shown in (A), and is obtained in the "sub-sharpness calculation" of step S107. Figure 15 The sharpness of (C).

[0266] Figure 24 It is a graph showing the order of the difference values ​​ΔAD obtained from the sensor electrodes 121 in rows of 5 and columns of 6, the absolute value of the variance of BigX(i), and the absolute value of the covariance of BigX(i) and BigY(i). Figure 24 (A) shows the order of the differential values ​​ΔAD obtained from the 5 rows and 6 columns of sensor electrodes 121. The sensor electrode 121 (2, 3) with the largest differential value ΔAD among the 30 is the 1st position, and the sensor electrode 121 (1, 6) with the smallest differential value ΔAD is the 30th position.

[0267] Figure 24 (B) indicates Figure 24 The difference value ΔAD shown in (A) represents the X coordinate (column j) and Y coordinate (row i) of the sensor electrodes 121 from the 1st to the 5th position. The sensor electrodes 121 from the 1st to the 5th position are the sensor electrodes 121 with the 1st to the 5th largest electrostatic capacitance values.

[0268] Figure 24 (C) shows the absolute value of the variance of BigX(i) (0.16) and the absolute value of the covariance of BigX(i) and BigY(i) (0.24) calculated from the X coordinates of the sensor electrodes 121 with the first to fifth largest electrostatic capacitance values. The statement "The absolute value of the covariance of BigX(i) and BigY(i) (0.24) calculated from the X and Y coordinates ≤ The absolute value of the variance of BigX(i) (0.16)" is not true. Therefore, in this example, the horizontal and vertical axes are not changed.

[0269] Figure 25 It means Figure 20 The diagram shown illustrates the determination result in the processing of the fingertip in the fourth variation example. Figure 25 As shown in (A), based on Figure 15 The sharpness of (C) is used to determine Figure 20 The results of determining "space," "finger," and "palm" in the processing of the fingertips are shown below. Figure 15 As shown in (C) from top to bottom, with sharpness values ​​of 0.00, 0.73, 0.41, 0.34, and 0.03, the values ​​are determined to be "space", "finger", "finger", "finger", and "palm".

[0270] Figure 25 (B) is the result of the loop processing for judging the fingers that emerge from the lower palm P, denoted as . Figure 25 The result of combining two of the five possible outcomes (A) sequentially from top to bottom is determined as either FALSE or TRUE. Here, the judgment is performed starting from the top. Figure 25 In (B), the topmost element is "space" and "finger," so it is FALSE. The second element from the top is "finger" and "finger," so it is FALSE. The third element from the top is "finger" and "finger," so it is FALSE. The fourth element from the top (the bottommost element) is "finger" and "palm," so it is TRUE. Since TRUE exists, it is determined that the fingers extended upwards from the palm P below.

[0271] Figure 25(C) represents the result of the loop processing to determine whether there is a fingertip FT in line i. Since the determination is based on the finger extending from the lower palm P, the determination is performed from the lower side. Figure 25 The judgment result of (A), such as Figure 25 As shown in (C), the fourth from the top (bottom) has row i as "finger" and row i-1 as "finger", so it's FALSE. The third from the top has row i as "finger" and row i-1 is also "finger", so it's FALSE. The second from the top has row i as "finger" and row i-1 as "space", so it's TRUE. There is no row i-1 at the top, so no judgment is made, indicated by "-". From the second row above the one that is TRUE, there is a fingertip FT.

[0272] Figure 25 (D) shows the result of determining the position of the fingertip. Column(2) of the minimum value in row 2 is based on... Figure 14 (C) is the 3rd column. Therefore, the 3rd column of the 2nd row refers to the position of the tip.

[0273] As described above, the position of the fingertip FT can be determined. Therefore, a non-contact input device 100A can be provided that can accurately determine the position of the fingertip FT located away from the sensor electrode 121.

[0274] <Determining the position of the fingertip FT in the sixth variation>

[0275] Next, use Figures 26 to 29 The flowchart illustrates the method for determining the position of the fingertip FT in the sixth variation. Figures 26 to 29 This is a flowchart illustrating the process of determining the position of the fingertip FT in the sixth variation. This process is performed by the decision unit 134. Figure 26 Indicates the main flow, Figures 27 to 29 They represent Figure 26 The process flow for subroutines in steps S134 to S136. Furthermore, regarding... Figure 26 The subroutine processing in steps S133, S137, and S138 is referenced. Figure 22 , Figure 13 as well as Figure 23 The functions "sub horizontal / vertical transformation", "sub row selection", and "sub horizontal / vertical return" are omitted here. Additionally, as an example, let's assume it can be used to transform from... Figure 3 The following describes the situation where the electronic device 100 is operated with its -Y, +Y, -X, and +X directions all facing the operation surface 105, and the hand H is placed over the electronic device 100 to perform operation input.

[0276] When processing begins, the determination unit 134 reads the number of rows and columns of the sensor electrodes 121 from the memory 137 (step S131). TemporalAllRows represents the number of rows of the sensor electrodes 121, and TemporalAllColumns represents the number of columns of the sensor electrodes 121. As an example, TemporalAllRows has 5 rows and TemporalAllColumns has 6 columns.

[0277] Next, the determination unit 134 obtains the difference values ​​ΔAD(1,1) to ΔAD(AllRows, AllColumns) for all sensor electrodes 121 and inputs them into TemporalCapa(1,1) to TemporalCapa(AllRows, AllColumns) (step S132). Through the processing in step S102, as an example, 30 difference values ​​TemporalCapa(1,1) to TemporalCapa(AllRows, AllColumns) for 30 sensor electrodes 121 are obtained.

[0278] Next, the decision unit 134 calls the subroutine "sub Transformation" (see reference). Figure 22 Subroutine "sub Transformation" (see reference) Figure 22 In other examples, the explanation ends, so the explanation is omitted.

[0279] Next, the decision unit 134 calls the subroutine "sub Maximum Value Decision" (see reference). Figure 27 ), determine the maximum value of Capacitance(i,j) for each row (step S134).

[0280] Next, decision unit 134 calls subroutine "sub except for determination" (see reference). Figure 28 The process involves identifying and excluding rows (step S135). Rows excluded refer to rows where no hand H exists. This process involves identifying and excluding rows where no hand exists, thereby filtering out rows where a hand exists.

[0281] Next, the decision unit 134 calls the subroutine "sub sharpness calculation" (see reference). Figure 29 For rows containing hands, the sharpness is calculated (step S136).

[0282] Next, the decision unit 134 calls the subroutine "sub Fingertip Determination" (see reference). Figure 13 Based on the sharpness calculated for all rows of the hand in step S136, the row of the fingertip FT is determined (step S137).

[0283] Next, decision unit 134 calls subroutine "sub cross return" (see reference). Figure 23 Then perform the horizontal and vertical return processing (step S138).

[0284] Finally, the determination unit 134 outputs the coordinates representing the position of the tip of the fingertip FT (step S139). Here, row represents the row number where the fingertip FT is located. In addition, column(i) represents the column number with the largest electrostatic capacitance value in row i, so column(Row) represents the column number with the largest electrostatic capacitance value in row row row.

[0285] Next, use Figure 27 , based on Figure 26 The maximum value determination process performed by the subroutine "sub Maximum Value Determination" in step S134 will be explained.

[0286] The determination unit 134 begins a cyclic process (steps S141 to S148) by selecting row i one by one from i=1 to AllRows and determining the maximum value of the electrostatic capacitance of each row i and its electrode. i=1, AllRows, 1 means that the process of determining the maximum value and its electrode is performed by selecting row by row from i=1 to AllRows.

[0287] The determination unit 134 sets the initial value of the maximum value of the electrostatic capacitance of row i, Maximum(i), to 0 (step S142). That is, Maximum(i) = 0.

[0288] The determination unit 134 begins a cyclic process (steps S143 to S147) in which column j is selected one by one from j=1 to AllColumns while determining the maximum value of the electrostatic capacitance value of row i and its electrode. j=1, AllColumns, 1 means that the process of determining the maximum value and its electrode is performed while selecting column by column from column j=1 to AllColumns.

[0289] The determination unit 134 determines whether the electrostatic capacitance value Capacitance(i) is greater than the maximum value Maximum(i) (step S144).

[0290] When the determination unit 134 determines that the electrostatic capacitance value Capacitance(i) is greater than the maximum value Maximum(i) (S144: Yes), it replaces the maximum value Maximum(i) with the electrostatic capacitance value Capacitance(i,j) (step S145). This is to update the maximum value Maximum(i) in the i-th row. The determination unit 134 stores the maximum value Maximum(i) in the i-th row updated in step S145 in the memory 137.

[0291] The determination unit 134 substitutes j into the column (i) that gives the maximum value Maximum(i) in the i-th row (step S146). That is, Column(i) = j. Column(i) represents the column number with the largest electrostatic capacitance value in the i-th row. The determination unit 134 stores the value obtained in step S146 in the memory 137.

[0292] For the selected row i, the determination unit 134 performs cyclic processing of steps S143 to S147 in order to determine the maximum value of the electrostatic capacitance and the sensor electrode 121(i,j) that gives the maximum value.

[0293] The determination unit 134 performs cyclic processing of steps S141 to S148 until the maximum value of the electrostatic capacitance value in all rows and the sensor electrode 121(i,j) that gives the maximum value are determined. Thus, the maximum value of the electrostatic capacitance value in all rows and the sensor electrode 121(i,j) that gives the maximum value are determined.

[0294] Next, use Figure 28 To explain based on Figure 26 The subroutine "sub Exclude Row Determination" in step S135 performs the determination of the excluded row.

[0295] The determination unit 134 performs a loop process (steps S151 to S154) on all rows i from i=1 to AllRows-1, where if the maximum value of the electrostatic capacitance value in row i is less than 1 / 2 of the maximum value of the electrostatic capacitance value in the next row i+1.

[0296] Here, the next row i+1 is the row adjacent to a row i in the -Y direction. i=1, AllRows-1, where 1 means that the excluded rows are determined while selecting row by row from row number i=1 to AllRows-1. The process is repeated up to row number AllRows-1 because there is no next row for row AllRows.

[0297] In the process of determining excluded rows, if the maximum value of the electrostatic capacitance in row i is less than half of the maximum value of the electrostatic capacitance in the next row i+1, then row i is excluded to find the leading edge of the fingertip FT. Rows overlapping with the leading edge of the fingertip FT have a large maximum value of electrostatic capacitance. Since the row preceding the row overlapping with the leading edge of the fingertip FT does not overlap with the leading edge of the fingertip FT, the maximum value of the electrostatic capacitance becomes smaller. In such rows overlapping with the leading edge of the fingertip FT and the row preceding it, the maximum value of the electrostatic capacitance differs considerably. Here, as an example, the position where the maximum value of the electrostatic capacitance is less than half is captured as the position of the row preceding the leading edge of the fingertip FT. If the maximum value of the electrostatic capacitance in row i is less than half of the maximum value of the electrostatic capacitance in the next row i+1, then row i is excluded. In this case, row i+1 overlaps with the leading edge of the fingertip FT, and row i is excluded because it does not overlap with the leading edge of the fingertip FT.

[0298] For the selected row i, the determination unit 134 determines whether the maximum value of the electrostatic capacitance value Maximum(i) in row i is less than 1 / 2 of the maximum value of the electrostatic capacitance value Maximum(i+1) in the next row i+1 (step S152).

[0299] If the determination unit 134 determines that the value is less than 1 / 2 (S152: Yes), then it substitutes "exclude" into Except1(i) (step S153A). The row i in Except1(i) that has "excluded" substituted is a row that is not included in the sharpness calculation described later. The determination unit 134 stores Except1(i) as arrangement data with row number i as the element in the memory 137.

[0300] On the other hand, if the determination unit 134 determines that it is not less than 1 / 2 (S152: No), it substitutes the "object" into Except1(i) (step S153B). The row i in Except1(i) in which the "object" is substituted is the row that can be the object of the sharpness calculation described later. The determination unit 134 stores Except1(i) as arrangement data with row number i as the element in the memory 137.

[0301] The determination unit 134 performs the cyclic processing of steps S151 to S154 for all rows i until the processing of rows i is terminated when the maximum value of the electrostatic capacitance in row i is less than 1 / 2 of the maximum value of the electrostatic capacitance in the next row i+1.

[0302] Next, the determination unit 134 sets the bottom row, AllRows, as the object row (step S155). That is, it sets Except1(AllRows) = "object". Since AllRows, which is the first bottom row, has no next row, it is set as an object here.

[0303] Next, the determination unit 134 performs a loop process for all rows i from i=2 to AllRows, where if the maximum value of the electrostatic capacitance value in row i is less than 1 / 2 of the maximum value of the electrostatic capacitance value in the previous row i-1, then row i is excluded (steps S156 to S159).

[0304] Here, row i-1 above is the row adjacent to row i in the +Y direction. i=2, AllRows, 1 means that rows are selected one by one from row number i=2 to AllRows while determining the excluded rows. Row number i=1 is set because there is no row above the top row.

[0305] In the process of determining which rows to exclude, row i is excluded if the maximum value of the electrostatic capacitance in row i is less than half of the maximum value of the electrostatic capacitance in row i-1 of the previous row. This is to prevent the space near the fingertip FT from being misidentified as a finger. Row i is excluded if it is less than half because if there is a fingertip FT in both row i and row i-1 of the previous row, the maximum value of the electrostatic capacitance in row i will not be less than half of the maximum value of the electrostatic capacitance in row i-1 of the previous row. Furthermore, this is consistent with the cyclic processing in steps S151 to S154.

[0306] For the selected row i, the determination unit 134 determines whether the maximum value of the electrostatic capacitance value Maximum(i) in row i is less than 1 / 2 of the maximum value of the electrostatic capacitance value Maximum(i-1) in the previous row i-1 (step S157).

[0307] If the determination unit 134 determines that the value is less than 1 / 2 (S157: Yes), then it determines that row i is an excluded row (Except2(i) = "excluded") (step S158A). Row i that is determined to be excluded is a row that is not included in the sharpness calculation described later. The determination unit 134 stores the determination result in step S158A as data with row number i as the element in memory 137.

[0308] On the other hand, if the determination unit 134 determines that it is not less than 1 / 2 (S157: No), it substitutes "object" into Except2(i) (step S158B). The row i in Except2(i) in which "object" is substituted is the row that can be the object of the sharpness calculation described later. The determination unit 134 stores the determination result in step S158B in memory 137 as the arrangement data of Except2(i) with row number i as the element.

[0309] The determination unit 134 performs cyclic processing of steps S156 to S159 for all rows i until the processing of rows i is terminated if the maximum value of the electrostatic capacitance in row i is less than 1 / 2 of the maximum value of the electrostatic capacitance in the previous row i-1.

[0310] Next, the determination unit 134 sets the top row, i.e., i=1, as the object row (step S160). That is, it substitutes "object" into Except2 (1). Since the top row does not have a previous row, it is set as an object here.

[0311] Next, the determination unit 134 starts a loop process for all rows i from i=1 to AllRows, where if the maximum value of the electrostatic capacitance value in row i is less than the determination threshold, row i is excluded (steps S161 to S164).

[0312] i = 1, AllRows. 1 means that rows are selected one by one from row number i = 1 to AllRows, while determining which rows to exclude. Furthermore, excluding row i if the maximum electrostatic capacitance value in row i is less than or close to the decision threshold is to determine whether fingertip FT exists in row i.

[0313] For the selected row i, the determination unit 134 determines whether the maximum value of the electrostatic capacitance value Maximum(i) in row i is less than the determination threshold (step S162).

[0314] When the determination unit 134 determines that the maximum value of the electrostatic capacitance, Maximum(i), is less than or close to the determination threshold (S162: Yes), it substitutes "Exclude" into Except3(i) (step S163A). The row i in Except3(i) in which "Exclude" is substituted is a row that is not included in the sharpness calculation described later. The determination unit 134 stores Except3(i) as arranged data with row number i as the element in the memory 137.

[0315] On the other hand, if the determination unit 134 determines that the maximum value of the electrostatic capacitance, Maximum(i), is not less than or close to the determination threshold (S162: No), then it substitutes the "object" into Except3(i) (step S163B). The row i in Except3(i) in which the "object" is substituted is the row that can be the object of the sharpness calculation described later. The determination unit 134 stores Except3(i) as arrangement data with row number i as the arrangement element in the memory 137.

[0316] The determination unit 134 performs cyclic processing of steps S161 to S164 for all rows i until the processing of rows i is terminated if the maximum value of the electrostatic capacitance value in row i is less than the determination threshold.

[0317] Next, the decision unit 134 performs a loop process (steps S165 to S168) in which row i is selected one by one from i=1 to AllRows and the row to be excluded is determined. i=1, AllRows, 1 means that the row to be selected for the purpose of determining the row to be excluded is selected one by one from i=1 to AllRows.

[0318] For the selected row i, the determination unit 134 determines whether Except1(i) = "object", Except2(i) = "object" and Except3(i) = "object" (step S166).

[0319] When the determination unit 134 determines "yes" in step S166, it substitutes "object" into Except(i) (step S167A). The row i in which Except(i) = "object" is substituted is the row that becomes the object of the sharpness calculation described later. The determination unit 134 stores Except(i) as arrangement data with row number i as the element in the memory 137.

[0320] On the other hand, if at least one of Except1(i), Except2(i), and Except3(i) is "excluded", then the determination unit 134 determines "no" in step S166. If the determination is "no" in step S166, then "excluded" is substituted into Except(i) (step S167B). Row i in which "excluded" is substituted into Except(i) is a row that is not subject to the sharpness calculation described later. The determination unit 134 stores Except(i) as arrangement data with row number i as an element in memory 137.

[0321] The determination unit 134 performs cyclic processing of steps S165 to S168 on all rows i until the processing of the excluded rows is completed. Through the above, the excluded row i is determined from all rows i.

[0322] Next, use Figure 29 To explain based on Figure 26 The subroutine "sub-sharpness calculation" in step S136 performs the sharpness calculation. Figure 29 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub Sharpness Calculation".

[0323] The determination unit 134 performs a loop process (steps S171 to S177) that selects row i one by one from i=1 to AllRows while calculating the sharpness. i=1, AllRows, 1 means that the sharpness is calculated while selecting row by row from row number i=1 to AllRows.

[0324] For the selected row i, the determination unit 134 determines whether it is an object with Except(i) = "object" (step S172). This is because if it is not an object, the sharpness is not calculated.

[0325] When the determination unit 134 determines that Except(i) = "object" (S172: yes), it determines whether the column Column(i) that gives the maximum value Maximum(i) in the i-th row is the first column (step S173). That is, it determines whether Column(i) = 1 for the i-th row. This is to determine whether the maximum value Maximum(i) in the i-th row is obtained in the first column (the column at the end on the -X direction side).

[0326] If the determination unit 134 determines that Column(i) is not 1 (S173: No), then it determines whether Column(i) is equal to AllColumns (step S174). That is, it determines whether Column(i) is equal to AllColumns for the i-th row. This is to determine whether the maximum value Maximum(i) in the i-th row is obtained from the column at the end of the +X direction side represented by AllColumns.

[0327] If the determination unit 134 determines that Column(i) is not equal to AllColumns (S174: No), then Column(i) is substituted into j (step S175A). That is, if Column(i) represents something other than the end, then Column(i) is substituted into j. Column(i) represents the column that shows the maximum value Maximum(i) in the i-th row (see step S26).

[0328] The determination unit 134 calculates the sharpness Apex(i) (step S176). The sharpness Apex(i) can be calculated according to the following formula. If the determination unit 134 calculates the sharpness Apex(i), it proceeds to step S177.

[0329] Apex(i)=-Capacitance(i,j-1)+2Capacitance(i,j)+Capacitance(i,j+1)

[0330] In step S172, if the determination unit 134 determines that Except(i) is not "object" (S172: No), then the sharpness Apex(i) is set to zero (step S172A). That is, 0 is substituted into the sharpness Apex(i). Since the row is not an object of the sharpness calculation, the sharpness Apex(i) is set to zero. As will be described later, the sharpness Apex(i) is used when determining the row where the fingertip is located. By setting a specific value (zero) for the sharpness Apex(i) of the row that is not an object of the sharpness calculation, the rows that are objects of the sharpness calculation and the rows that are not objects of the sharpness calculation can be processed in the same step. As will be described later, in this embodiment, if sharpness is calculated, a positive value is calculated. As will be described later, the row with the highest sharpness is determined to be the row with the fingertip. Therefore, setting the sharpness Apex(i) to zero is equivalent to setting row i as not a fingertip.

[0331] Furthermore, if the determination unit 134 determines in step S173 that Column(i) = 1 (S173: Yes), then it sets j = 2 (step S173A). This is because, since the column Column(i) that gives the maximum value Maximum(i) in the i-th row is the column at the end of the -X direction side (column 1), the column j, which is the middle of the three columns used for sharpness calculation, is set as column 2, and the sharpness is calculated using the three reciprocals of columns 1 to 3. If the determination unit 134 ends the processing in step S173A, it proceeds to step S176 to calculate the sharpness.

[0332] Furthermore, if the determination unit 134 determines in step S174 that Column(i) = AllColumns (S174: Yes), it sets j = AllColumns-1 (step S175B). Since the column Column(i) that gives the maximum value Maximum(i) in the i-th row is the column at the end of the +X direction (the 6th column represented by AllColumns), the column j, the middle column of the three columns used for sharpness calculation, is set to AllColumns-1 (the 5th column), and the sharpness is calculated using the three reciprocals from the 4th to the 6th columns. If the determination unit 134 ends the processing in step S175B, it proceeds to step S176 to calculate the sharpness.

[0333] The determination unit 134 performs the loop processing of steps S171 to S177 for all rows i until the sharpness calculation is completed.

[0334] <Handling of Sharpness in the Seventh Variation>

[0335] Figure 30 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the seventh variation. Figure 30 The process shown makes the process of step S176 similar to... Figure 29 The processing of step S176 shown is different. Here, for... Figure 29 The differences in the processing shown are explained.

[0336] exist Figure 30 In the process shown, the determination unit 134 calculates the curvature of the circle passing through the following three points as the sharpness Apex(i) (step S176). The three points are represented by (j-1, Capacitance(i, j-1)), (j, Capacitance(i, j)), and (j+1, Capacitance(i, j+1)).

[0337] Here, in the xy coordinate system where column j is set as the x-axis and the capacitance value Capacitance is set as the y-axis, j-1, j, and j+1 are set as x1, x2, and x3, respectively, and Capacitance(i, j-1), Capacitance(i, j), and Capacitance(i, j+1) are set as y1, y2, and y3, respectively. This is a replacement for... Figure 17 The electrostatic capacitance value (Capacitance) is set as the y-axis by using Reciprocal as the reciprocal of the y-axis. (Illustration omitted here.)

[0338] The decision unit 134 calculates the radius r of the circle passing through the three points in the same way, and inputs the curvature (the reciprocal of the radius, 1 / r) to the sharpness Apex(i). That is, the sharpness Apex(i) = 1 / r.

[0339] <Handling of Sharpness in the Eighth Variation>

[0340] Figure 31 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the eighth variant. Figure 31 The process shown makes the process of step S176 similar to... Figure 29 The processing of step S176 shown is different. Here, for... Figure 29 The differences in the processing shown are explained.

[0341] exist Figure 31In the process shown, the decision unit 134 uses 5 adjacent points in row i to obtain a quadratic curve that approximates the 5 points by curve fitting and the least squares method. Therefore, the coefficient of the quadratic curve is calculated as the sharpness Apex(i) (step S176).

[0342] The five adjacent points in row i are (j-2, Capacitance(i, j-2)), (j-1, Capacitance(i, j-1)), (j, Capacitance(i, j)), (j+1, Capacitance(i, j+1)), and (j+2, Capacitance(i, j+2)). If the decision unit 134 calculates the sharpness Apex(i), it proceeds to step S177.

[0343] <Handling of Sharpness Calculation in the Ninth Variation>

[0344] Figure 32 This is a flowchart illustrating the process of calculating sharpness based on the subroutine "sub-sharpness calculation" of the ninth variation. Figure 32 The process shown makes the process of step S176 similar to... Figure 29 The processing of step S176 shown is different. Here, for... Figure 29 The differences in the processing shown are explained.

[0345] exist Figure 32 In the process shown, the decision unit 134 uses 5 adjacent points in row i to perform curve fitting using the least squares method to find the circumference that approximates the 5 points, and calculates the curvature of the circumference as the sharpness Apex(i) (step S176).

[0346] The five adjacent points in row i are (j-2, Capacitance(i, j-2)), (j-1, Capacitance(i, j-1)), (j, Capacitance(i, j)), (j+1, Capacitance(i, j+1)), and (j+2, Capacitance(i, j+2)). If the decision unit 134 calculates the sharpness Apex(i), it proceeds to step S177.

[0347] <Structure of electrostatic sensor 120>

[0348] Figure 33 This is a diagram showing the specific structure of the electrostatic sensor 120 of the non-contact input device 100A.

[0349] The electrostatic sensor 120 is stacked on top of the display device 110, such as... Figure 33As shown, the sensor 120 has multiple sensor electrodes 121X extending in the X direction and multiple sensor electrodes 121Y extending in the Y direction. The sensor electrodes 121X and 121Y are connected to the control device 130 via wirings 122X and 122Y, respectively. As an example, such an electrostatic sensor 120 can be an electrostatic sensor in which a transparent conductive film such as ITO (Indium Tin Oxide) is formed on the surface of transparent glass, and patterns are formed on the sensor electrodes 121X and 121Y and the wirings 122X and 122Y. The electrostatic capacitance of the electrostatic sensor 120 is input to the control device 130.

[0350] exist Figure 33 In the example shown, there are 12 sensor electrodes 121X and 20 sensor electrodes 121Y. The row and column relationship of the 12 sensor electrodes 121X and 20 sensor electrodes 121Y is the same as that of the operation unit 111. Therefore, there are 12 rows of sensor electrodes 121X and 20 columns of sensor electrodes 121Y. The number of rows of sensor electrodes 121X and the number of columns of sensor electrodes 121Y are just one example.

[0351] The 12 rows of sensor electrodes 121X are scanned row by row, and the 20 columns of sensor electrodes 121Y are scanned column by column. The AD converter 132 converts the electrostatic capacitance at the 240 intersection points of the 12 rows of sensor electrodes 121X and the 20 columns of sensor electrodes 121Y into digital values. The counter 133 counts the changes in the output of the AD converter 132 and outputs the difference value ΔAD at the 240 intersection points. Hereinafter, (i, j) represents the coordinates of the intersection points. Here, row i is 1 to 12, and column j is 1 to 20.

[0352] The above describes a contactless input device with exemplary embodiments of the present invention. However, the present invention is not limited to the specific embodiments disclosed, and various modifications and alterations can be made without departing from the scope of the claims.

Claims

1. A contactless input device, characterized in that, include: Multiple sensor electrodes detect the electrostatic capacitance corresponding to the approach state of a hand that performs non-contact operation input to the operation surface of the operation unit towards the operation surface; as well as The determination unit calculates the sharpness of the hand at multiple different positions when viewed from above, based on the electrostatic capacitance detected by the plurality of sensor electrodes, and determines the position of the operation input based on the plurality of sharpness values. The plurality of sensor electrodes are configured in a lattice shape. The determination unit calculates the sharpness by performing curve fitting based on the reciprocal of the electrostatic capacitance along a straight line along the arrangement direction of the plurality of sensor electrodes. The determination unit also calculates the sharpness of each of the other straight lines parallel to the straight line.

2. The contactless input device according to claim 1, wherein, The determination unit calculates the sharpness by performing curve fitting based on the reciprocal of the electrostatic capacitance of 2n+1 sensor electrodes, including the sensor electrode whose reciprocal of electrostatic capacitance is the minimum, along a straight line along the arrangement direction of the plurality of sensor electrodes.

3. The contactless input device according to claim 2, wherein, The determination unit compares the minimum value of the reciprocals of the electrostatic capacitances on adjacent straight lines. The position corresponding to the reciprocal of the electrostatic capacitance that is a given multiple of the reciprocal of the electrostatic capacitance on the adjacent straight line is considered as space.

4. The contactless input device according to claim 3, wherein, The determination unit compares the minimum value of the reciprocals of each electrostatic capacitance with the value close to the determination threshold. The space is defined as the position corresponding to the reciprocal of the electrostatic capacitance that is larger than the threshold value.

5. The contactless input device according to any one of claims 2 to 4, wherein, When a sensor electrode whose reciprocal of the electrostatic capacitance along a straight line along the arrangement direction of the plurality of sensor electrodes is minimized is separated from the ends of the plurality of sensor electrodes by more than n, the determination unit calculates the sharpness by curve fitting based on the reciprocal of the electrostatic capacitance of the sensor electrode whose reciprocal of the electrostatic capacitance along the straight line along the arrangement direction of the plurality of sensor electrodes is minimized, and the reciprocal of the electrostatic capacitance of the 2n+1 sensor electrodes on each side of that sensor electrode. If a sensor electrode whose reciprocal of the electrostatic capacitance along a straight line along the arrangement direction of the plurality of sensor electrodes is at its minimum value has not moved more than n times from the ends of the plurality of sensor electrodes, the determination unit calculates the sharpness by curve fitting based on the reciprocal of the electrostatic capacitance of the 2n+1 sensor electrodes from the ends along a straight line along the arrangement direction of the plurality of sensor electrodes.

6. The contactless input device according to claim 1, wherein, The plurality of sensor electrodes are configured in a lattice shape. The determination unit calculates the sharpness by performing curve fitting based on the electrostatic capacitance of 2n+1 sensor electrodes, including the sensor electrode whose electrostatic capacitance reaches its maximum value, along a straight line along the arrangement direction of the plurality of sensor electrodes. The determination unit also calculates the sharpness of each of the other straight lines parallel to the straight line.

7. The contactless input device according to claim 6, wherein, The determination unit compares the maximum values ​​of the electrostatic capacitances on adjacent straight lines. The position corresponding to the electrostatic capacitance that is a given multiple smaller than the electrostatic capacitance on the adjacent straight line is considered as space.

8. The contactless input device according to claim 7, wherein, The determination unit compares the maximum value of each electrostatic capacitance with a value close to a determination threshold. The location corresponding to the electrostatic capacitor smaller than the proximity determination threshold is considered as space.

9. The contactless input device according to any one of claims 6 to 8, wherein, If the sensor electrode whose electrostatic capacitance along the straight line along the arrangement direction of the plurality of sensor electrodes reaches its maximum value is located more than n times from the ends of the plurality of sensor electrodes, the determination unit calculates the sharpness by performing curve fitting based on the electrostatic capacitance of the sensor electrode whose electrostatic capacitance along the straight line along the arrangement direction of the plurality of sensor electrodes reaches its maximum value and the electrostatic capacitance of the 2n+1 sensor electrodes located n times from each side of that sensor electrode. If the sensor electrode whose electrostatic capacitance on a straight line along the arrangement direction of the plurality of sensor electrodes reaches its maximum value is more than n times away from the end, the determination unit calculates the sharpness by curve fitting based on the electrostatic capacitance of 2n+1 sensor electrodes from the end on a straight line along the arrangement direction of the plurality of sensor electrodes.

10. The contactless input device according to any one of claims 2 to 4, wherein, The determination part is fitted with a quadratic function as the curve fitting, and the coefficient of the second quadratic function is calculated as the sharpness.

11. The contactless input device according to any one of claims 2 to 4, wherein, The determination part is fitted to a circle as the curve fitting, and the curvature of the circle is calculated as the sharpness.

12. The contactless input device according to any one of claims 2 to 4, wherein, The number of sensor electrodes used by the determination unit to calculate the sharpness is three.

13. The contactless input device according to any one of claims 2 to 4, wherein, The number of sensor electrodes used by the determination unit to calculate the sharpness is five or more, and the determination unit uses the least squares method to perform curve fitting to calculate the sharpness.

14. The contactless input device according to any one of claims 2 to 4, wherein, Along a straight line along the configuration direction of the plurality of sensor electrodes, the 2n+1 consecutively adjacent sensor electrodes are arranged with a length of more than 10 mm and less than 100 mm.

15. The contactless input device according to any one of claims 1 to 4, wherein, The determination unit determines the position corresponding to the sharpest of the plurality of sharpnesses as the position of the operation input.

16. The contactless input device according to any one of claims 1 to 4, wherein, The determination unit determines the position of the finger as the position of the finger corresponding to the sharpness above the threshold representing the sharpness of the finger among the plurality of sharpnesses.

17. The contactless input device according to claim 16, wherein, The determination unit determines the position of the palm as the position of the sharpness that is less than the threshold representing the sharpness of a finger among the plurality of sharpnesses. The determination unit determines the position of the tip of the finger on the side opposite to the position of the palm as the position of the operation input.

18. The contactless input device according to any one of claims 1 to 4, wherein, The contactless input device and the display device are arranged overlappingly. The determination unit calculates the sharpness along a straight line along the transverse direction of the display device.

19. The contactless input device according to any one of claims 1 to 4, wherein, The determination unit considers the line obtained by approximating the position of the electrostatic capacitance of the plurality of sensor electrodes, which is larger than that of a given number of sensor electrodes, using the least squares method, as the finger direction. The determination unit determines the direction for calculating the sharpness, such that the angle between the direction for calculating the sharpness and the finger direction is increased.

20. The contactless input device according to any one of claims 1 to 4, wherein, The plurality of sensor electrodes are arranged in a rectangular configuration.

21. The contactless input device according to any one of claims 1 to 4, wherein, The contactless input device has multiple orthogonal wirings. Each sensor electrode is formed through the intersection of the wiring.

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