Input device

Abstract

This input device is provided with: a plurality of electrostatic sensor electrodes that detect electrostatic capacitance values between the electrostatic sensor electrodes and an operating body present in a space; and a control device that detects a position of the operating body in the space on the basis of the electrostatic capacitance values detected by the plurality of electrostatic sensor electrodes. The control device calculates an input position on the basis of a maximum value of differences between the electrostatic capacitance values of adjacent electrostatic sensor electrodes.

Description

Input Device

[0001] The present invention relates to an input device.

[0002] Patent Document 1 below discloses a technique for detecting a region occupied by an indicator at a position spaced apart from a touch panel by means of a transmission electrode and a reception electrode.

[0003] Japanese Unexamined Patent Publication No. 2014-178868

[0004] However, since the technique of Patent Document 1 compares a capacitance value with a threshold value, a region that is not the edge position of a finger is detected. Accordingly, the shape of the detected region changes depending on the orientation of the finger and the like, and misjudgment is likely to occur.

[0005] An input device according to one embodiment comprises: a plurality of capacitive sensor electrodes that detect capacitance values between the input device and an operating object existing in space; and a control device that detects the position of the operating object in space based on the capacitance values detected by the plurality of capacitive sensor electrodes, wherein the control device calculates an input position based on the maximum value of differences between capacitance values of adjacent capacitive sensor electrodes.

[0006] According to the input device of one embodiment, the edge position of the operating object can be detected with high accuracy.

[0007] Figure 1 shows a schematic configuration of an input device according to one embodiment. Figure 1 shows a plan view showing the configuration of the electrostatic sensor included in the input device according to one embodiment. Figure 1 shows an example of stereoscopic display by the input device according to one embodiment. Figure 1 shows an example of control of stereoscopic display by the control device included in the input device according to one embodiment (first example). Figure 1 shows an example of control of stereoscopic display by the control device included in the input device according to one embodiment (second example). Figure 1 shows an example of processing procedure by the control device included in the input device according to one embodiment (first example). Figure 1 shows an example of processing procedure by the control device included in the input device according to one embodiment (second example). Figure 1 shows an example of processing procedure by the control device included in the input device according to one embodiment (third example). Figure 1 shows an example of processing procedure by the control device included in the input device according to one embodiment (fourth example). A flowchart showing an example of a processing procedure by the control device (4th example) A flowchart showing an example of a processing procedure by the control device provided in the input device according to the embodiment (5th example) A flowchart showing an example of a peripheral data copy processing procedure shown in Figure 12 A flowchart showing an example of a second derivative processing procedure shown in Figure 12 A flowchart showing an example of a maximum value processing procedure shown in Figure 12 A flowchart showing another example of a peripheral data copy processing procedure shown in Figure 12 A flowchart showing another example of a second derivative processing procedure shown in Figure 12 A flowchart showing an example of a method for detecting the edge of an operable object by the control device provided in the input device according to the embodiment (1st example) A diagram showing an example of a method for detecting the edge of an operable object by the control device provided in the input device according to the embodiment (2nd example) A diagram showing an example of a method for detecting the edge of an operable object by the control device provided in the input device according to the embodiment (3rd example) A diagram showing an example of a method for detecting the edge of an operable object by the control device provided in the input device according to the embodiment (4th example)

[0008] An embodiment will be described below with reference to the drawings. For convenience, in the following description, the Z-axis direction in the drawings will be considered as the vertical direction, the Y-axis direction as the left-right direction, and the X-axis direction as the front-back direction. However, the positive Z-axis direction will be considered upward, the positive Y-axis direction as the rightward direction, and the positive X-axis direction as the forward direction.

[0009] (Configuration of Input Device 100) Figure 1 is a diagram showing the schematic configuration of an input device 100 according to one embodiment. As shown in Figure 1, the input device 100 comprises a housing 110, a light source 120, a beam splitter 130, a retroreflective member 140, an electrostatic sensor 150, and a control device 160. The light source 120, the beam splitter 130, and the retroreflective member 140 constitute the "display means".

[0010] The housing 110 is a resin, box-shaped component that has a storage space.

[0011] The light source 120 is located inside the housing 110 and emits light toward the beam splitter 130. For example, an LED (Light Emitting Diode) is used as the light source 120.

[0012] The beam splitter 130 is a flat plate-shaped member mounted horizontally on the upper surface of the housing 110. The beam splitter 130 has the properties of transmitting and reflecting light. The beam splitter 130 reflects the light emitted from the light source 120 toward the retroreflective member 140.

[0013] The retroreflective member 140 is a flat plate-shaped member provided inside the housing 110. The retroreflective member 140 has the property of reflecting light. The retroreflective member 140 reflects the light reflected by the beam splitter 130 back towards the beam splitter 130. The light reflected by the retroreflective member 140 passes through the beam splitter 130 and forms an aerial image 10 above the housing 110.

[0014] The electrostatic sensor 150 is mounted horizontally on the upper surface of the housing 110. The electrostatic sensor 150 detects the position of the operating body 20 (for example, the operator's finger) above the housing 110. Specifically, the electrostatic sensor 150 has a plurality of electrostatic sensor electrodes 151 (see Figure 2), and the position of the operating body 20 is detected by capacitance using these plurality of electrostatic sensor electrodes 151.

[0015] The control device 160 is located inside the housing 110 and performs various controls on the input device 100. For example, the control device 160 controls the display content of the aerial image 10, the display and hiding of the aerial image 10, etc., by controlling the light emission from the light source 120. Also, for example, the control device 160 performs various processes according to the position of the operating body 20 detected by the electrostatic sensor 150 (for example, changing the display content of the aerial image 10, displaying and hiding the aerial image 10, outputting operation signals to external devices, etc.).

[0016] The input device 100, having the above-described configuration of its "display means," can display multiple aerial images 10 above the upper surface of the housing 110 (i.e., at a height suitable for operation by the operating body 20). The control device 160 can control the display and non-display of the aerial images 10 by controlling the on and off of the light source 120.

[0017] In particular, the control device 160 can hide the aerial image 10 that overlaps with the area enclosed by the edge of the operating body 20 by turning off the light source 120 corresponding to the area enclosed by the edge of the operating body 20. This allows the control device 160 to prevent the operator from experiencing the unnatural appearance of the operating body 20 appearing to pass through the aerial image 10 by hiding the aerial image 10 that overlaps with the operating body 20. The position of the edge of the operating body 20 refers to the planar position of the operating body 20; that is, it refers to the XY coordinates of the edge of the operating body 20.

[0018] The input device 100 may also include a "display means" which may have a shutter (for example, a liquid crystal) between the light source 120 and the beam splitter 130. In this case, the control device 160 can control the display and hiding of the aerial image 10 by controlling the opening and closing state of the shutter.

[0019] In particular, the control device 160 may control the opening and closing state of the shutter to hide the light source 120 corresponding to the area enclosed by the edge of the operating body 20 with the shutter, thereby hiding the aerial image 10 that overlaps with the area enclosed by the edge of the operating body 20. In this case, by hiding the aerial image 10 at the position overlapping with the operating body 20, the control device 160 can prevent the operator from experiencing the unnatural feeling that the operating body 20 is passing through the aerial image 10.

[0020] The control device 160 includes a processor (e.g., a CPU (Central Processing Unit)), a storage device (e.g., a ROM (Read Only Memory), a RAM (Random Access Memory)), and other components. The processor executes programs stored in the storage device to perform various controls on the input device 100. An integrated circuit (IC) is used as the control device 160.

[0021] (Configuration of the electrostatic sensor 150) Figure 2 is a plan view showing the configuration of the electrostatic sensor 150 provided in the input device 100 according to one embodiment. As shown in Figure 2, the electrostatic sensor 150 has a configuration in which a plurality of electrostatic sensor electrodes 151 are arranged in the left-right direction (Y-axis direction). Each of the plurality of electrostatic sensor electrodes 151 has a strip shape that has a constant left-right width and extends linearly in the front-back direction (X-axis direction). Each of the plurality of electrostatic sensor electrodes 151 is a plate-shaped or thin-film member made of a conductor. When an operating body 20 (for example, the operator's finger) comes into close proximity to each of the plurality of electrostatic sensor electrodes 151, the capacitance increases by capacitive coupling with the operating body 20.

[0022] (An example of stereoscopic display by the input device 100) Figure 3 shows an example of stereoscopic display by the input device 100 according to one embodiment. In the input device 100 shown in Figure 3, six aerial images 10-1 to 10-6 are displayed above the housing 110 at the same height, arranged in the left-right direction (Y-axis direction). Each aerial image 10-1 to 10-6 is a plate-like shape with a rectangular shape in plan view, and is tilted so that the front side (positive X-axis side) is higher than the back side (negative X-axis side) so that the surface faces the operator side (negative X-axis side).

[0023] (An example of control of stereoscopic display by the control device 160 (first example)) Figure 4 shows an example of control of stereoscopic display by the control device 160 provided in the input device 100 according to one embodiment (first example).

[0024] As a first example of controlling the 3D display, the control device 160 hides the aerial image 10 that overlaps with the left edge of the operating body 20, and the aerial image 10 to the right of the aerial image 10 overlapping with the left edge of the operating body 20 (positive Y-axis side), and displays the aerial image 10 to the left of the aerial image 10 overlapping with the left edge of the operating body 20 (negative Y-axis side).

[0025] For example, Figure 4 shows an example where the operating body 20 (operator's finger) is moved to the left (negative direction of the Y axis) above the housing 110.

[0026] In the example shown in Figure 4(a), the operating body 20 is located to the right of the input device 100 (positive Y-axis side), meaning it does not overlap with any of the aerial images 10-1 to 10-6, and therefore all of the aerial images 10-1 to 10-6 are displayed.

[0027] The example shown in Figure 4(b) shows the state in which the operating body 20 has moved to the left from the state shown in Figure 4(a). In the example shown in Figure 4(b), the left edge of the operating body 20 overlaps with the aerial image 10-6. In this case, the control device 160 detects this overlap using an electrostatic sensor and hides the aerial image 10-6 as shown in Figure 4(b).

[0028] The example shown in Figure 4(c) shows the state after the operator 20 has moved to the left from the state shown in Figure 4(b). In the example shown in Figure 4(c), the left edge of the operator 20 overlaps with the aerial image 10-5. That is, the left edge of the operator 20 does not overlap with the aerial image 10-6. However, since the control device 160 hides the aerial image 10 to the right (positive Y-axis side) of the aerial image 10 that overlaps with the left edge of the operator 20, it hides not only the aerial image 10-5 but also the aerial image 10-6, as shown in Figure 4(d).

[0029] The example shown in Figure 4(d) shows the state in which the operating body 20 has moved to the left from the state shown in Figure 4(c). In the example shown in Figure 4(d), the left edge of the operating body 20 overlaps with the aerial image 10-5. The control device 160 hides the aerial image 10 to the right (positive Y-axis side) of the aerial image 10 that overlaps with the edge of the operating body 20, and as shown in Figure 4(d), it hides aerial images 10-5 and 10-6.

[0030] Therefore, when the left edge of the operating body 20 overlaps only with the aerial image 10-1 located on the far left (negative Y-axis side), the control device 160 hides aerial image 10-1 and aerial images 10-2 to 10-6 to its right (positive Y-axis side), thus hiding all aerial images 10-1 to 10-6.

[0031] As shown in Figure 4, the control device 160 does not display the aerial image 10 that overlaps with the left edge of the operating body 20, nor the aerial image 10 to the right of it, but displays the aerial image 10 to the left of the edge of the operating body 20. This allows the control device 160 to intuitively and easily understand that the edge is the input position.

[0032] (An example of control of stereoscopic display by the control device 160 (second example)) Figure 5 shows an example (second example) of control of stereoscopic display by the control device 160 provided in the input device 100 according to one embodiment.

[0033] As a second example of controlling the 3D display, the control device 160 hides the aerial images 10 that overlap with the edge of the operating body 20 and displays the aerial images 10 that do not overlap with the edge of the operating body 20.

[0034] For example, Figure 5 shows an example in which the operating body 20 is moved to the left (negative Y-axis direction) above the housing 110.

[0035] In the example shown in Figure 5(a), the operating body 20 is located to the right of the input device 100 (positive Y-axis side), meaning it does not overlap with any of the aerial images 10-1 to 10-6, and therefore all of the aerial images 10-1 to 10-6 are displayed.

[0036] The example shown in Figure 5(b) shows the state after the operating body 20 has moved to the left from the state shown in Figure 5(a). In the example shown in Figure 5(b), the left edge of the operating body 20 overlaps with the aerial image 10-6. In this case, the control device 160 detects this overlap using an electrostatic sensor and hides the aerial image 10-6 as shown in Figure 5(b).

[0037] The example shown in Figure 5(c) shows the state after the operating body 20 has moved to the left from the state shown in Figure 5(b). In the example shown in Figure 5(c), the left edge of the operating body 20 overlaps with the aerial image 10-5, and the right edge of the operating body 20 overlaps with 10-6. In this case, the control device 160 detects this overlap using an electrostatic sensor and hides the two aerial images 10-5 and 10-6, as shown in Figure 5(c).

[0038] The example shown in Figure 5(d) shows the state in which the operating body 20 has moved to the left from the state shown in Figure 5(c). In the example shown in Figure 5(d), the left and right edges of the operating body 20 overlap only with the aerial image 10-5. That is, the edges of the operating body 20 do not overlap with the aerial image 10-6. In this case, the control device 160 hides only the aerial image 10 that overlaps with the edges of the operating body 20, so as shown in Figure 5(d), only the aerial image 10-5 is hidden and the aerial image 10-6 is displayed.

[0039] Therefore, the control device 160, for example, displays only aerial image 10-1 when the edge of the operating body 20 overlaps with only the aerial image 10-1 located on the leftmost side (negative Y-axis side), and displays aerial images 10-2 to 10-6.

[0040] As shown in Figure 5, the control device 160 calculates the position of one (right) edge and the position of the other (left) edge of the operating body 20, and displays the aerial images 10 to the right of the position of the right edge and to the left of the position of the other (left) edge (i.e., the aerial images 10 in which the operating body 20 does not overlap), while not displaying the aerial images 10 between the position of one edge and the position of the other edge of the operating body 20 (i.e., the aerial images 10 in which the operating body 20 overlaps). By doing so, the control device 160 can prevent the operator from experiencing the unnatural feeling that the operating body 20 is passing through the aerial images 10 by hiding the aerial images 10 in the position where the operating body 20 overlaps.

[0041] (Example of a processing procedure by the control device 160 (first example)) Figure 6 is a flowchart showing an example of a processing procedure by the control device 160 provided in the input device 100 according to one embodiment (first example).

[0042] First, the control device 160 sets a threshold value for the variable Max and sets the variable Cmax to "0" as an initial value (step S201). The threshold value is used to determine the presence or absence of a finger. The variable Max is the maximum value of the difference in capacitance values ​​between adjacent electrostatic sensor electrodes 151. The variable Cmax is the position where the capacitance value between adjacent electrostatic sensor electrodes 151 is maximum.

[0043] Next, the control device 160 measures the capacitance value of the first electrostatic sensor electrode 151 from the left among the multiple electrostatic sensor electrodes 151 provided by the electrostatic sensor 150 (step S202). Then, the control device 160 sets the variable Cleft to the capacitance value measured in step S202 (step S203). The variable Cleft is the capacitance value of the leftmost electrostatic sensor electrode 151 among the adjacent electrostatic sensor electrodes 151.

[0044] Next, the control device 160 repeatedly executes steps S204 to S210 as measurement and adjacent calculation processing. Here, when the number of electrostatic sensor electrodes 151 is n, the start value of the variable i indicating the position from the left of the electrostatic sensor electrode 151 to be processed is set to "2", the end value is set to n, and the increment is set to "1".

[0045] In step S204, the control device 160 measures the capacitance value of the i-th electrostatic sensor electrode 151 from the left among the plurality of electrostatic sensor electrodes 151 included in the electrostatic sensor 150 (step S204). Then, the control device 160 sets the capacitance value measured in step S204 to the variable Cright (step S205). The variable Cright is the capacitance value of the right electrostatic sensor electrode 151 among adjacent electrostatic sensor electrodes 151.

[0046] Next, the control device 160 calculates Cdiff=Cright-Cleft (step S206). The variable Cdiff is the difference between the capacitance values of adjacent electrostatic sensor electrodes 151. When the capacitance value Cright of the right electrostatic sensor electrode 151 among adjacent electrostatic sensor electrodes 151 is high and the capacitance value Cleft of the left electrostatic sensor electrode 151 is low, Cdiff becomes large. From the left end of the finger to the right side, since the electrostatic sensor electrode 151 faces the finger, the capacitance value becomes large. On the other hand, the area to the left of the left end of the finger is a space without a finger, so the capacitance value of the electrostatic sensor electrode 151 becomes small. Therefore, Cdiff becomes large at the position facing the left end of the finger.

[0047] Then, the control device 160 determines whether Cdiff>Max is satisfied (step S207).

[0048] When it is determined in step S207 that Cdiff>Max is not satisfied (step S207: NO), the control device 160 advances the process to step S210.

[0049] In step S207, if it is determined that Cdiff > Max is satisfied (step S207: YES), the control device 160 sets the value of the variable Cdiff to the variable Max (step S208). The control device 160 also sets the value of the variable i to the variable Cmax (step S209). Then, the control device 160 proceeds to step S210.

[0050] In step S210, the control device 160 sets the value of the variable Cright to the variable Cleft, and terminates the measurement and adjacent calculation processing for the i-th electrostatic sensor electrode 151 from the left.

[0051] The control device 160 performs measurement and adjacent position calculation processing for all electrostatic sensor electrodes 151 from the i-th to the nth position from the left, and then proceeds to step S211.

[0052] In step S211, the control device 160 determines whether or not Cmax≠0 is satisfied (step S211).

[0053] In step S211, if it is determined that Cmax≠0 is not satisfied (step S211: NO), the control device 160 turns on all light sources (step S215). After that, the control device 160 terminates the series of processes shown in Figure 6. As mentioned above, in step S201, the initial value of Cmax is set to 0 and Max is set to the threshold. When there are no fingers on any of the electrostatic sensor electrodes, the difference in capacitance values ​​of all adjacent electrostatic sensor electrodes becomes less than or equal to the threshold, and Cmax=0.

[0054] In step S211, if it is determined that Cmax ≠ 0 is satisfied (step S211: YES), the control device 160 outputs the variable Cmax (step S212). The control device 160 also turns on the light sources from the leftmost to the Cmax-1th position (step S212). The control device 160 also turns off the light sources from the Cmax position to the rightmost position (step S214). After that, the control device 160 completes the series of processes shown in Figure 6.

[0055] According to the flowchart shown in Figure 6, the control device 160 can detect the position where the difference in capacitance values ​​between adjacent electrostatic sensor electrodes 151 is maximum, which is the edge of the operator's finger. Then, as illustrated in Figure 4, the control device 160 can turn on the light source to the left of the edge of the operator's left finger, and turn off the light source to the right of the left edge of the operator's finger, including the left edge of the operator's finger.

[0056] In particular, as shown in the flowchart in Figure 6, the control device 160 can calculate the position of the edge of the operating body 20 based on a position greater than a reference value based on the maximum difference in capacitance values ​​of adjacent electrostatic sensor electrodes 151. This allows the control device 160 to detect the position of the edge of the operating body 20 with high accuracy.

[0057] Furthermore, according to the flowchart shown in Figure 6, the control device 160 calculates a first subtraction value for each combination of adjacent electrostatic sensor electrodes 151 by subtracting the capacitance value of the other (left) electrostatic sensor electrode 151 from the capacitance value of the other (right) electrostatic sensor electrode 151. The position of the one (right) electrostatic sensor electrode 151 in the combination that maximizes the first subtraction value can then be calculated as the position of the left edge of the operating body 20.

[0058] This allows the control device 160 to detect the position of the other (left) edge of the operating body 20 with high precision.

[0059] (An example of a processing procedure by the control device 160 (second example)) Figure 7 is a flowchart showing an example of a processing procedure by the control device 160 provided in the input device 100 according to one embodiment (second example).

[0060] First, the control device 160 sets a threshold value for the variable Maxp, sets a negative threshold value for the variable Maxm, sets the variable Cmaxp to "0" as an initial value, and sets the variable Cmaxm to "0" as an initial value (step S301). The threshold value is the value used to determine the presence or absence of a finger. The variable Maxp is the maximum value of the difference in capacitance values ​​between adjacent electrostatic sensor electrodes 151. The variable Maxm is the minimum value of the difference in capacitance values ​​between adjacent electrostatic sensor electrodes 151. The variable Cmaxp is the position where the capacitance value between adjacent electrostatic sensor electrodes 151 is maximum (i.e., the position of the left end of the operator's finger). The variable Cmaxm is the position where the capacitance value between adjacent electrostatic sensor electrodes 151 is minimum (i.e., the position of the right end of the operator's finger).

[0061] Next, the control device 160 measures the capacitance value of the first electrostatic sensor electrode 151 from the left among the multiple electrostatic sensor electrodes 151 provided by the electrostatic sensor 150 (step S302). Then, the control device 160 sets the variable Cleft to the capacitance value measured in step S302 (step S303). The variable Cleft is the capacitance value of the leftmost electrostatic sensor electrode 151 among the adjacent electrostatic sensor electrodes 151.

[0062] Next, the control device 160 repeatedly executes steps S304 to S313 as measurement and adjacent calculation processing. Here, if the number of electrostatic sensor electrodes 151 is n, the starting value of the variable i, which indicates the position of the electrostatic sensor electrode 151 to be processed from the left, is set to "2", the ending value to "n", and the increment is set to "1".

[0063] In step S304, the control device 160 measures the capacitance value of the i-th electrostatic sensor electrode 151 from the left among the multiple electrostatic sensor electrodes 151 provided by the electrostatic sensor 150 (step S304). Then, the control device 160 sets the variable Cright to the capacitance value measured in step S304 (step S305). The variable Cright is the capacitance value of the rightmost electrostatic sensor electrode 151 among the adjacent electrostatic sensor electrodes 151.

[0064] Next, the control device 160 calculates Cdiff = Cright - Cleft (step S306). The variable Cdiff is the difference in capacitance values ​​between adjacent electrostatic sensor electrodes 151. As mentioned above, the capacitance value of the electrostatic sensor electrode 151 is large from the left end of the finger to the right. On the other hand, the capacitance is small to the left of the left end of the finger. For this reason, Cdiff is maximum at the left end of the finger. Conversely, the capacitance is large to the left of the right end of the finger. On the other hand, the capacitance is small to the right of the right end of the finger. For this reason, Cdiff is minimum at the right end of the finger (it becomes a negative value with a large absolute value).

[0065] Then, the control device 160 determines whether or not Cdiff > Maxp is satisfied (step S307).

[0066] If it is determined in step S307 that Cdiff > Maxp is not satisfied (step S307: NO), the control device 160 determines whether or not Cdiff < Max is satisfied (step S310).

[0067] If it is determined in step S310 that Cdiff < Maxm is not satisfied (step S310: NO), the control device 160 proceeds to step S313.

[0068] In step S310, if it is determined that Cdiff < Maxm is satisfied (step S310: YES), the control device 160 sets the variable Maxm to the value of the variable Cdiff (step S311). The control device 160 also sets the variable Cmaxm to the value of the variable i-1 (step S312). Then, the control device 160 proceeds to step S313. The position corresponding to variable i is the position opposite to the space to the right of the right end of the finger. The position opposite the right end of the finger is the position corresponding to variable i-1.

[0069] In step S307, if it is determined that Cdiff > Maxp is satisfied (step S307: YES), the control device 160 sets the value of the variable Cdiff to the variable Maxp (step S308). The control device 160 also sets the value of the variable i to the variable Cmaxp (step S309). Then, the control device 160 proceeds to step S313.

[0070] In step S313, the control device 160 sets the value of the variable Cright to the variable Cleft, and ends the measurement and adjacent calculation processing for the i-th electrostatic sensor electrode 151 counted from the left.

[0071] After the control device 160 executes the measurement, adjacent calculation processing and position calculation processing for all the i-th to n-th electrostatic sensor electrodes 151 counted from the left, the control device 160 advances the processing to step S314.

[0072] In step S314, the control device 160 determines whether or not Cmaxp≠0 and Cmaxm≠0 are satisfied (step S314).

[0073] When it is determined in step S314 that Cmaxp≠0 and Cmaxm≠0 are satisfied (step S311: YES), the control device 160 determines whether or not Cmaxp<Cmaxm is satisfied (step S315).

[0074] When it is determined in step S314 that Cmaxp≠0 and Cmaxm≠0 are not satisfied (step S314: NO), or when it is determined in step S315 that Cmaxp<Cmaxm is not satisfied (step S315: NO), the control device 160 turns on all the light sources (step S318). Thereafter, the control device 160 ends the series of processing shown in FIG. 7. Steps S314 and S315 determine whether both ends of the finger have been normally recognized. When both ends of the finger are recognized, Cmaxp>0 and Cmaxm>0. That is, if Cmaxp=0 or Cmaxm=0, either the right end or the left end of the finger has not been recognized. In this case, the control device 160 turns on all the light sources to indicate that the finger has not been recognized. In addition, if the positional relationship between the left end and the right end of the finger is reversed, the position of the finger has not been correctly recognized, therefore, if Cmaxp<Cmaxm, the control device 160 turns on all the light sources.

[0075] In step S315, if it is determined that Cmaxp ≠ 0 and Cmaxm ≠ 0 are satisfied (step S315: YES), the control device 160 outputs (Cmaxp + Cmaxm) / 2 (step S316). The control device 160 also turns off the light sources from Cmaxp to Cmaxm (step S317). After that, the control device 160 completes the series of processes shown in Figure 7.

[0076] According to the flowchart shown in Figure 7, the control device 160 considers the position where the difference in capacitance values ​​of adjacent electrostatic sensor electrodes 151 is maximum as the left edge (the other edge) of the operator's finger, and the position where the difference in capacitance values ​​of adjacent electrostatic sensor electrodes 151 is minimum as the right edge (the other edge) of the operator's finger. The edge position is the side with the larger capacitance value among the combinations where the absolute value of the difference in capacitance values ​​of adjacent electrostatic sensor electrodes 151 is large. That is, at the left end of the finger (the other edge), the electrostatic sensor electrode on the right side (the other side) is at the edge position. On the other hand, at the right end of the finger (the other edge), the electrostatic sensor electrode on the left side (the other side) is at the edge position. Then, as illustrated in Figure 4, the control device 160 can turn off the light source in the area overlapping with the operator's finger (i.e., the area between the left edge and the right edge) and turn on the light source in the area not overlapping with the operator's finger (i.e., the area to the left of the left edge and the area to the right of the right edge). Due to measurement errors (especially in resolution), the actual position of the fingertip and the calculated fingertip position differ. However, the calculated fingertip position is treated as the edge, and the aerial image is controlled accordingly.

[0077] Furthermore, according to the flowchart shown in Figure 7, the control device 160 can further calculate the position of the other electrostatic sensor electrode 151 among the combinations that minimize the first subtraction value, as the position of the right edge of the operating body 20.

[0078] As a result, the control device 160 can detect the position of the other (left) edge of the operating body 20 with high precision. In other words, the control device 160 can determine the range of the operating body 20 based on the position of the one (right) edge of the operating body 20 and the position of the other (left) edge of the operating body 20.

[0079] (Example of a processing procedure by the control device 160 (third example)) Figure 8 is a flowchart showing an example of a processing procedure by the control device 160 provided in the input device 100 according to one embodiment (third example).

[0080] First, the control device 160 repeatedly executes step S401 as a measurement process. Here, if the number of electrostatic sensor electrodes 151 is n, the starting value of the variable i, which indicates the position of the electrostatic sensor electrode 151 to be processed from the left, is set to "1", the ending value to n, and the increment is set to "1".

[0081] In step S401, the control device 160 sets the variable C(i) to the measured capacitance value (step S401).

[0082] The control device 160 performs measurement processing for all electrostatic sensor electrodes 151 from the i-th to the nth-th from the left, and then proceeds to step S402.

[0083] In step S402, the control device 160 sets the value of variable C(1) to variable C(0) and sets the value of variable C(n) to variable C(n+1) (step S402). Next, the control device 160 sets a threshold value for variable Max (step S403).

[0084] Next, the control device 160 repeatedly executes steps S404 to S406 as a calculation process. Here, if the number of electrostatic sensor electrodes 151 is n, the starting value of the variable i, which indicates the position of the electrostatic sensor electrode 151 to be processed from the left, is set to "1", the ending value to n, and the increment is set to "1".

[0085] In step S404, the control device 160 calculates C2diff(i) = 2 × C(i) - C(i-1) - C(i+1) (step S404). C2diff is the value obtained by differentiating the capacitance value twice.

[0086] Next, the control device 160 determines whether the condition C2diff(i)>Max is satisfied (step S405).

[0087] In step S405, if it is determined that the condition C2diff(i) > Max is satisfied (step S405: YES), the control device 160 sets the value of the variable C2diff(i) to the variable Max (step S406). After that, the control device 160 finishes the calculation process for the i-th electrostatic sensor electrode 151 from the left.

[0088] If, in step S405, it is determined that the condition C2diff(i)>Max is not satisfied (step S405: NO), the control device 160 terminates the calculation process for the i-th electrostatic sensor electrode 151 from the left.

[0089] The control device 160 performs calculation processing for all electrostatic sensor electrodes 151 from the i-th to the nth position from the left, and then repeatedly executes steps S407 to S408 as edge identification processing. Here, if the number of electrostatic sensor electrodes 151 is n, the starting value of the variable i, which indicates the position of the electrostatic sensor electrode 151 to be processed from the left, is set to "1", the ending value to "n", and the increment is set to "1".

[0090] In step S407, the control device 160 determines whether the condition C2diff(i) > coefficient × Max is satisfied (step S407). For example, "0.5" is used as the coefficient.

[0091] In step S407, if it is determined that the condition C2diff(i) > coefficient × Max is satisfied (step S407: YES), the control device 160 sets the variable Edge(i) to "True" (step S408). After that, the control device 160 terminates the edge identification process for the i-th electrostatic sensor electrode 151 from the left.

[0092] In step S407, if it is determined that the condition C2diff(i) > coefficient × Max is not satisfied (step S407: NO), the control device 160 terminates the edge identification process for the i-th electrostatic sensor electrode 151 from the left.

[0093] The control device 160 performs edge identification processing for all electrostatic sensor electrodes 151 from the i-th to the nth-th from the left, and then proceeds to step S409.

[0094] In step S409, the control device 160 outputs the central position between the two edges as the input position (step S409).

[0095] Next, the control device 160 hides the display of the region enclosed by the coordinates where Edge(i) = True (step S410). After that, the control device 160 completes the series of processes shown in Figure 8.

[0096] According to the flowchart shown in Figure 8, the control device 160 can detect the position of the electrostatic sensor electrode 151 where the value obtained by the second derivative of the capacitance value (C2diff(i)) is greater than the threshold (coefficient × Max), as the edge of the operator's finger. The control device 160 can then hide the display of the area enclosed by the multiple detected edges, as this area overlaps with the operator's finger.

[0097] Furthermore, according to the flowchart shown in Figure 8, the control device 160 calculates a third subtraction value by multiplying the capacitance value of the electrostatic sensor electrode 151 to be calculated by a predetermined coefficient, and then subtracting the capacitance values ​​of a plurality of electrostatic sensor electrodes 151 adjacent to the electrostatic sensor electrode 151 to be calculated. The position where this value is greater than the value obtained by multiplying the maximum value of the third subtraction value by a predetermined coefficient can be calculated as the edge position of the operating body 20.

[0098] In this example, the control device 160 performs a second derivative at the edge of the finger, where the change in capacitance value is discontinuous, resulting in a large value for the second derivative. Therefore, the control device 160 can accurately detect the position where the value of the second derivative is maximum as the position of the edge of the operating body 20.

[0099] In particular, according to the flowchart shown in Figure 8, the control device 160 can calculate a third subtraction value by multiplying the capacitance value of the electrostatic sensor electrode 151 to be calculated by a predetermined coefficient of 2, and then subtracting the capacitance values ​​of the two electrostatic sensor electrodes adjacent to the left and right of the electrostatic sensor electrode 151 to be calculated.

[0100] (Example of processing procedure by control device 160 (4th example)) Figures 9 to 11 are flowcharts showing an example of a processing procedure (4th example) by the control device 160 provided in the input device 100 according to one embodiment.

[0101] Here, we show an example in which multiple electrostatic sensor electrodes 151 are arranged in a grid pattern in m rows and i columns.

[0102] First, the control device 160 measures the capacitance value of all electrostatic sensor electrodes 151 in m rows and i columns, and sets the measured capacitance value in the variable C(i,j) (step S501).

[0103] Next, the control device 160 repeatedly executes step S502 and the column calculation process for each row of electrostatic sensor electrodes 151 as a row calculation process. Here, if the number of rows of electrostatic sensor electrodes 151 is m, the starting value of the variable j indicating the row of electrostatic sensor electrode 151 to be processed is set to "1", the ending value to m, and the increment is set to "1".

[0104] In step S502, the control device 160 sets a threshold value for the variable Maxp, sets a threshold value for the variable Maxm, sets the variable Cmaxp to 0, and sets the variable Cmaxm to 0 (step S502).

[0105] In each column calculation process, the control device 160 repeatedly executes steps S503 to S509 for each column of the electrostatic sensor electrodes 151. Here, if the number of columns of the electrostatic sensor electrodes 151 is n, the starting value of the variable i, which indicates the column of the electrostatic sensor electrodes 151 to be processed, is set to "2", the ending value to "n", and the increment is set to "1".

[0106] In step S503, the control device 160 calculates Cdiff = C(i,j) - C(i-1,j) (step S503).

[0107] Next, the control device 160 determines whether the condition Cdiff > Maxp is satisfied (step S504).

[0108] In step S504, if it is determined that the condition Cdiff>Maxp is satisfied (step S504: YES), the control device 160 sets Maxp=Cdiff (step S505). Further, the control device 160 sets Clmaxplus(i,j)="Maxplus" (step S506). Thereafter, the control device 160 ends each column calculation process for the i-th column of the electrostatic sensor electrodes 151.

[0109] In step S504, if it is determined that the condition Cdiff>Maxp is not satisfied (step S504: NO), the control device 160 determines whether or not the condition Cdiff<Maxm is satisfied (step S507).

[0110] In step S507, if it is determined that the condition Cdiff<Maxm is satisfied (step S507: YES), the control device 160 sets Maxm=Cdiff (step S508). Further, the control device 160 sets Clmaxminus(i-1,j)="Maxminus" (step S509). Thereafter, the control device 160 ends each column calculation process for the i-th column of the electrostatic sensor electrodes 151.

[0111] In step S507, if it is determined that the condition Cdiff<Maxm is not satisfied (step S507: NO), the control device 160 ends each column calculation process for the i-th column of the electrostatic sensor electrodes 151.

[0112] After the control device 160 executes each row calculation process for all rows of the electrostatic sensor electrodes 151, the control device 160 advances the process to each row calculation process shown in FIG. 10.

[0113] In each row calculation process shown in FIG. 10, the control device 160 repeatedly executes step S510 and each column calculation process in units of rows of the electrostatic sensor electrodes 151. Here, when the number of rows of the electrostatic sensor electrodes 151 is n, the starting value of the variable i indicating the row of the electrostatic sensor electrode 151 to be processed is "1", the ending value is n, and the increment is "1".

[0114] In step S510, the control device 160 sets a threshold for the variable Maxp, sets a threshold for the variable Maxm, sets 0 for the variable Cmaxp, and sets 0 for the variable Cmaxm (step S510).

[0115] In each column calculation process, the control device 160 repeatedly executes steps S511 to S517 in units of columns of the capacitive sensor electrodes 151. Here, when the number of columns of the capacitive sensor electrodes 151 is m, the starting value of the variable j indicating the column of the capacitive sensor electrode 151 to be processed is set to "2", the ending value is set to m, and the increment is set to "1".

[0116] In step S511, the control device 160 calculates Cdiff=C(i,j)-C(i-1,j) (step S511).

[0117] Next, the control device 160 determines whether or not the condition Cdiff>Maxp is satisfied (step S512).

[0118] When it is determined in step S512 that the condition Cdiff>Maxp is satisfied (step S512: YES), the control device 160 sets Maxp=Cdiff (step S513). Further, the control device 160 sets Cvmaxp(i,j)="maxplus" (step S514). Thereafter, the control device 160 ends each column calculation process for the j-th column of the capacitive sensor electrodes 151.

[0119] When it is determined in step S512 that the condition Cdiff>Maxp is not satisfied (step S512: NO), the control device 160 determines whether or not the condition Cdiff<Maxm is satisfied (step S515).

[0120] When it is determined in step S515 that the condition Cdiff<Maxm is satisfied (step S515: YES), the control device 160 sets Maxm=Cdiff (step S516). Further, the control device 160 sets Cvmaxm(j,j-1)="Maxminus" (step S517). Thereafter, the control device 160 ends each column calculation process for the j-th column of the capacitive sensor electrodes 151.

[0121] In step S515, if it is determined that the condition Cdiff<Maxm is not satisfied (step S515: NO), the control device 160 ends each column calculation process for the j-th column of capacitive sensor electrodes 151.

[0122] After executing each row calculation process for all rows of capacitive sensor electrodes 151, the control device 160 advances the process to each column edge position specifying process and each row edge position specifying process shown in FIG. 11.

[0123] In the column edge position specifying process and the row edge position specifying process shown in FIG. 11, the control device 160 specifies whether each of all m-row i-column capacitive sensor electrodes 151 is an edge by executing steps S518 to S519.

[0124] In step S518, the control device 160 determines whether any of the following conditions is satisfied: condition Cvmaxp(i,j)="maxplus", condition Cvmaxm(j,j)="Maxminus", condition Clmaxplus(i,j)="Maxplus", or condition Clmaxminus(i,j)="Maxminus" (step S518).

[0125] In step S518, if it is determined that any of the four above conditions is satisfied (step S518: YES), the control device 160 sets "True" to the variable Edge(i,j) (step S519), and ends the edge position specifying process for said capacitive sensor electrode 151.

[0126] In step S518, if it is determined that none of the four above conditions is satisfied (step S518: NO), the control device 160 ends the edge position specifying process for said capacitive sensor electrode 151.

[0127] After ending the edge position specifying process for all m-row i-column capacitive sensor electrodes 151, the control device 160 advances the process to step S520.

[0128] In step S520, the control device 160 outputs, as an input position, a position among the plurality of positions determined to be edges for which the opposing side has not been determined to be an edge (step S520)

[0129] Next, the display of the area enclosed by the border is hidden (step S521). After that, the control device 160 completes the series of processes shown in Figures 9 to 11.

[0130] According to the flowcharts shown in Figures 9 to 11, the control device 160 can identify the position where the difference in capacitance value between adjacent electrostatic sensor electrodes 151 is maximized for each of the multiple electrostatic sensor electrodes 151 arranged in a grid pattern in m rows and i columns, and this position is identified as the edge of the operator's finger. The control device 160 can then hide the display of the area enclosed by the identified multiple edges, as this area overlaps with the operator's finger.

[0131] In particular, according to the flowcharts shown in Figures 9 to 11, the control device 160 calculates a first subtraction value for each combination of horizontally adjacent electrostatic sensor electrodes 151 by subtracting the capacitance value of the other (left) electrostatic sensor electrode 151 from the capacitance value of the other (right) electrostatic sensor electrode 151. The position of the right electrostatic sensor electrode in the combination of electrostatic sensor electrodes that maximizes the first subtraction value is calculated as the position of the left edge (first edge) of the operating body, and the position of the other electrostatic sensor electrode in the combination of electrostatic sensor electrodes that minimizes the first subtraction value is calculated as the position of the right edge (second edge) of the operating body.

[0132] Furthermore, the control device 160 can calculate a second subtraction value for each combination of vertically adjacent electrostatic sensor electrodes 151 by subtracting the capacitance value of one electrostatic sensor electrode 151 from the capacitance value of the other electrostatic sensor electrode 151. The control device 160 can then calculate the position of one electrostatic sensor electrode 151 in the combination of electrostatic sensor electrodes 151 that maximizes the second subtraction value as the position of the third edge of the operating body 20, and calculate the position of the other electrostatic sensor electrode 151 in the combination of electrostatic sensor electrodes that minimizes the second subtraction value as the position of the fourth edge of the operating body 20.

[0133] As a result, the control device 160 can detect both vertical edges and both horizontal edges of the operating body 20 with high precision based on the capacitance values ​​of the multiple electrostatic sensor electrodes 151 arranged in a grid. In other words, the control device 160 can detect the area around the operating body 20 with high precision.

[0134] (An example of a processing procedure by the control device 160 (5th example)) Figure 12 is a flowchart showing an example of a processing procedure by the control device 160 provided in the input device 100 according to one embodiment (5th example).

[0135] Here, we show an example in which multiple electrostatic sensor electrodes 151 are arranged in a grid pattern in m rows and i columns.

[0136] First, the control device 160 measures the capacitance value of all electrostatic sensor electrodes 151 in m rows and i columns, and sets the measured capacitance value in the variable C(i,j) (step S601).

[0137] Next, the control device 160 performs the peripheral data copy process shown in Figure 13 (step S602).

[0138] Next, the control device 160 performs the second derivative processing shown in Figure 14 (step S603).

[0139] Next, the control device 160 performs the maximum value processing shown in Figure 15 (step S604).

[0140] Next, the control device 160 performs column edge position identification processing and row edge position identification processing to determine whether or not all electrostatic sensor electrodes 151 in column m and row i are edges by performing steps S605 to S606.

[0141] In step S605, the control device 160 determines whether the condition C(i,j) > coefficient × Max is satisfied (step S605). For example, "0.3" is used as the coefficient.

[0142] In step S605, if it is determined that the condition C(i,j) > coefficient × Max is satisfied (step S605: YES), the control device 160 sets the variable Edge(i,j) to "True" (step S606) and terminates the edge position determination process for the electrostatic sensor electrode 151.

[0143] If, in step S605, it is determined that the condition C(i,j) > coefficient × Max is not satisfied (step S605: NO), the control device 160 terminates the edge position identification process for the electrostatic sensor electrode 151.

[0144] After the control device 160 has finished the edge position identification process for all electrostatic sensor electrodes 151 in column m and row i, it proceeds to step S607.

[0145] In step S607, the control device 160 outputs the center in the short direction of the side where the edges are calculated, which is the longitudinal end of the area enclosed by the edges, as the input position (i.e., the center in the width direction of the tip of the operator's finger) (step S607).

[0146] Next, the control device 160 hides the display of the area enclosed by the edges (Edge(i,j)=True) (step S608). After that, the control device 160 completes the series of processes shown in Figure 12.

[0147] In particular, according to the flowchart shown in Figure 12, the control device 160 can detect two rows of edges facing each other and one row of edges connecting the ends of the two rows of edges, and in step S409, it can output the central position of the one row of edges as the input position.

[0148] Furthermore, according to the flowchart shown in Figure 12, the control device 160 can detect two rows of opposing longitudinal edges and one row of transverse edges connecting the ends of the two rows of longitudinal edges, and output the central position of the transverse edge as the input position.

[0149] As a result, the control device 160 can output the central part of the fingertip position of the operating body 20 as the input position in non-contact input using the electrostatic sensor 150.

[0150] (An example of the procedure for copying peripheral data) Figure 13 is a flowchart showing an example of the procedure for copying peripheral data shown in Figure 12.

[0151] In the peripheral data copying process, the control device 160 first repeatedly executes step S701 for each row of electrostatic sensor electrodes 151 as a front and back copying process.

[0152] In step S701, the control device 160 sets the value of variable C(i,1) to variable C(i,0) and sets the value of variable C(i,m) to variable C(i,m+1) (step S701).

[0153] Next, the control device 160 first repeatedly executes step S702 in units of rows of electrostatic sensor electrodes 151 as left and right end copies.

[0154] In step S702, the control device 160 sets the value of variable C(1,j) to variable C(0,j) and sets the value of variable C(n,j) to variable C(n+1,j) (step S702).

[0155] After the control device 160 has finished copying the left and right edges of all rows of electrostatic sensor electrodes 151, it terminates the series of processes shown in Figure 13.

[0156] (An example of the procedure for second differentiation) Figure 14 is a flowchart showing an example of the procedure for second differentiation shown in Figure 12.

[0157] The control device 160 performs a second derivative operation by executing a column calculation process and a row calculation process for each column, thereby performing the second derivative of the capacitance value for all electrostatic sensor electrodes 151 in m columns and i rows by executing step S801.

[0158] In step S801, the control device 160 calculates sd(i,j) = 4*C(i,j) - C(i-1,j) - C(i+1,j) - C(i,j-1) - C(i,j+1) (step S801).

[0159] The control device 160 performs second-order differentiation on all electrostatic sensor electrodes 151 in column m and row i, and then completes the series of processes shown in Figure 14.

[0160] (Example of Maximum Value Processing Procedure) Figure 15 is a flowchart showing an example of the maximum value processing procedure shown in Figure 12.

[0161] In maximum value processing, the control device 160 first sets a threshold value for the variable Max (step S901).

[0162] Next, the control device 160 performs steps S902 to S903 for all electrostatic sensor electrodes 151 in m columns and i rows by performing column processing and row processing.

[0163] In step S902, the control device 160 determines whether the condition C(i,j)>Max is satisfied (step S902).

[0164] In step S902, if it is determined that the condition C(i,j)>Max is satisfied (step S902: YES), the control device 160 sets the value of variable C(i,j) to variable Max (step S903) and terminates processing for the electrostatic sensor electrode 151.

[0165] If, in step S902, it is determined that the condition C(i,j)>Max is not satisfied (step S902: NO), the control device 160 terminates processing for the electrostatic sensor electrode 151.

[0166] The control device 160 performs steps S902 to S903 for all electrostatic sensor electrodes 151 in column m and row i, and then proceeds to step S904.

[0167] In step S904, the control device 160 determines whether the condition Max=threshold is met (step S904).

[0168] In step S904, if it is determined that the condition Max ≤ threshold is met (step S904: YES), the control device 160 sets the variable Max to 0xFFFF (an example of the maximum value on the system) (step S905), and terminates the series of processes shown in Figure 14.

[0169] If, in step S904, it is determined that the condition Max ≤ threshold is not met (step S904: NO), the control device 160 terminates the series of processes shown in Figure 14.

[0170] (Another example of the procedure for copying peripheral data) Figure 16 is a flowchart showing another example of the procedure for copying peripheral data shown in Figure 12. The peripheral data copying procedure shown in Figure 16 corresponds to calculations in the vertical, horizontal, and diagonal directions.

[0171] The peripheral data copy process shown in Figure 16 differs from the peripheral data copy process shown in Figure 13 in that it performs step S700.

[0172] In step S700, the control device 160 sets the value of variable C(1,1) to variable C(0,0), sets the value of variable C(n,1) to variable C(n+1,0), sets the value of variable C(1,m) to variable C(0,m+1), and sets the value of variable C(n,m) to variable C(n+1,m+1) (step S700).

[0173] (Another example of the procedure for second differentiation) Figure 17 is a flowchart showing another example of the procedure for second differentiation shown in Figure 12. The second differentiation shown in Figure 17 corresponds to calculations in the vertical, horizontal, and diagonal directions.

[0174] The second derivative operation shown in Figure 17 differs from the second derivative operation shown in Figure 14 in that it performs step S801-2 instead of step S801.

[0175] In step S801-2, the control device 160 calculates sd(i,j) = 8*C(i,j) - C(i-1,j) - C(i+1,j) - C(i,j-1) - C(i,j+1) - C(i-1,j-1) - C(i+1,j-1) - C(i-1,j+1) - C(i+1,j+1) (step S801-2).

[0176] According to the flowcharts shown in Figures 12 to 17, the control device 160 calculates a third subtraction value by multiplying the capacitance value of the electrostatic sensor electrode 151 to be calculated by a predetermined coefficient, and then subtracting the capacitance values ​​of a plurality of electrostatic sensor electrodes 151 adjacent to the electrostatic sensor electrode 151 to be calculated. The position where this value is greater than the value obtained by multiplying the maximum value of the third subtraction value by a predetermined coefficient can be calculated as the edge position of the operating body 20.

[0177] As a result, the control device 160 performs a second derivative. At the edge of the finger, the change in capacitance value is discontinuous, so the value of the second derivative becomes large. Therefore, the control device 160 can accurately detect the position where the value of the second derivative is maximum as the position of the edge of the operating body 20.

[0178] In particular, the control device 160 can calculate a third subtraction value by performing the peripheral data copy processing and second derivative processing shown in Figures 13 and 14. This is done by multiplying the capacitance value of the electrostatic sensor electrode 151 to be calculated by 4 as a predetermined coefficient, and then subtracting the capacitance values ​​of the four electrostatic sensor electrodes 151 adjacent to the electrostatic sensor electrode 151 in the front, back, left, and right directions. In other words, the control device 160 can calculate the third subtraction value by processing similar to that of a four-neighbor Laplacian filter used for image processing.

[0179] Furthermore, the control device 160 can calculate a third subtraction value by performing the peripheral data copy processing and second derivative processing shown in Figures 16 and 17. This is done by multiplying the capacitance value of the electrostatic sensor electrode 151 to be calculated by 8 as a predetermined coefficient, and then subtracting the capacitance values ​​of eight electrostatic sensor electrodes 151 that are diagonally adjacent to the electrostatic sensor electrode 151 in the front, back, left, right, and right directions. In other words, the control device 160 can calculate the third subtraction value by processing similar to that of an 8-nearest neighbor Laplacian filter for image processing, thereby enabling the position of the edge of the operating body 20 to be calculated with greater accuracy.

[0180] (An example of a method for detecting the edge of the operating body 20 (first example)) Figure 18 shows an example (first example) of a method for detecting the edge of the operating body 20 by a control device 160 provided in an input device 100 according to one embodiment.

[0181] In the example shown in Figure 18, the electrostatic sensor 150 has 10 rows of electrostatic sensor electrodes 151 arranged horizontally. Figure 18(a) shows the detected capacitance values ​​of each electrostatic sensor electrode 151. Figure 18(b) shows the difference in capacitance values ​​between each electrostatic sensor electrode 151 and adjacent electrostatic sensor electrodes 151. Figure 18(c) shows the determination position of the edge of the operating body 20.

[0182] The control device 160 determines the capacitance value for each electrostatic sensor electrode 151, as shown in Figure 18(a), by executing the flowchart shown in Figure 6, Figure 7, or Figure 8.

[0183] Then, as shown in Figure 18(b), the control device 160 calculates the difference in capacitance value between it and the adjacent electrostatic sensor electrode 151 on the left. In the example shown in Figure 18(b), the electrostatic sensor electrode 151 in the first column from the left does not have an adjacent electrostatic sensor electrode 151 on its left, so the difference in capacitance value between it and the adjacent electrostatic sensor electrode 151 is not calculated.

[0184] Furthermore, as shown in Figure 18(c), the control device 160 detects the position of the electrostatic sensor electrode 151 where the multiple differences obtained reach their maximum value (L) and minimum value (S), as the position of the edge of the operating body 20.

[0185] For example, in the example shown in Figure 18, the control device 160 detects the position of the electrostatic sensor electrode 151 in the fifth column from the left as the position of the left edge of the operating body 20 because it is the maximum value of the above difference, and the position of the electrostatic sensor electrode 151 in the seventh column from the left as the position of the right edge of the operating body 20 because it is the minimum value of the above difference.

[0186] (An example of a method for detecting the edge of the operating body 20 (second example)) Figure 19 shows an example (second example) of a method for detecting the edge of the operating body 20 by the control device 160 provided in the input device 100 according to one embodiment. Figure 19 explains an example of determining the position of the edge of the operating body 20 by executing the flowchart (first derivative case) shown in Figures 9 to 11.

[0187] In the example shown in Figure 19, the electrostatic sensor 150 has 10 rows of electrostatic sensor electrodes 151 arranged horizontally and 10 rows of electrostatic sensor electrodes 151 arranged vertically, arranged in a grid pattern. Figure 19(a) shows the detected capacitance value of each electrostatic sensor electrode 151. Figure 19(b) shows the difference in capacitance value of each electrostatic sensor electrode 151 with adjacent electrostatic sensor electrodes 151 in the left-right direction. Figure 19(c) shows the difference in capacitance value of each electrostatic sensor electrode 151 with adjacent electrostatic sensor electrodes 151 in the front-back direction. Figure 19(d) shows the determination position of the edge of the operating body 20.

[0188] For example, as shown in Figure 19(b), the control device 160 calculates the difference in lateral capacitance values ​​between adjacent electrostatic sensor electrodes 151. For example, it calculates "-58" by subtracting "83" in the 6th row, 7th column from "25" in the 6th row, 8th column. In the example shown in Figure 19(b), the electrostatic sensor electrode 151 in the 1st column from the left does not have an adjacent electrostatic sensor electrode 151 to its left, so the difference in capacitance value between it and the adjacent electrostatic sensor electrode 151 is not calculated.

[0189] Next, as shown in Figure 19(c), the control device 160 calculates the difference in vertical capacitance values ​​between adjacent electrostatic sensor electrodes 151. In the example shown in Figure 19(c), the electrostatic sensor electrode 151 in the first row from the bottom does not have an adjacent electrostatic sensor electrode 151 below it, so the difference in capacitance values ​​between it and the adjacent electrostatic sensor electrode 151 is not calculated.

[0190] Next, as shown in Figure 19(d), the control device 160 detects the position of the electrostatic sensor electrode 151 where the calculated differences in the lateral direction reach their maximum value (L) and minimum value (S), and uses these positions as the position of the first edge of the operating body 20 and the position of the second edge of the operating body. However, even if the difference between adjacent electrostatic sensor electrodes 151 is the maximum or minimum in the lateral direction, the control device 160 does not use that electrostatic sensor electrode 151 as an edge position if its absolute value is less than a threshold.

[0191] In other words, the difference in capacitance values ​​of horizontally adjacent electrostatic sensor electrodes 151 is greater than or equal to a threshold and is the maximum or minimum combination within the same row, with the electrode with the larger capacitance value being the horizontal edge. Also, in combinations where the difference in capacitance values ​​of horizontally adjacent electrostatic sensor electrodes 151 is large, a finger is above the electrode with the larger capacitance value, and there is space above the electrode with the smaller capacitance value.

[0192] If your finger is above your right hand and there is empty space above your left hand, subtracting the left hand from the right hand will result in a larger value. In this case, the right hand is the leftmost end of your finger. Also, if your finger is above your right hand and there is empty space above your left hand, subtracting the left hand from the right hand will result in a smaller value (a negative value with a large absolute value). In this case, the left hand is the rightmost end of your finger.

[0193] Furthermore, as shown in Figure 19(e), the control device 160 detects the positions of the electrostatic sensor electrodes 151 where the calculated differences in the vertical direction reach their maximum and minimum values, as the positions of the third edge and the fourth edge of the operating body 20, respectively. In the example in Figure 19(e), the position of the third edge of the operating body is not detected, while the position of the fourth edge of the operating body is detected. However, even if the difference between adjacent electrostatic sensor electrodes 151 is the maximum or minimum in the vertical direction, the control device 160 does not consider that electrostatic sensor electrode 151 to be an edge position if its absolute value is less than a threshold.

[0194] In other words, the difference in capacitance values ​​of vertically adjacent electrostatic sensor electrodes 151 is greater than or equal to a threshold and is the maximum or minimum within the same row, with the electrode with the larger capacitance value being the vertical edge. Also, in combinations where the difference in capacitance values ​​of vertically adjacent electrostatic sensor electrodes 151 is large, a finger is above the electrode with the larger capacitance value, and there is space above the electrode with the smaller capacitance value.

[0195] If a finger is positioned above the far side and there is empty space above the near side, subtracting the near side from the far side will result in a larger value. In this case, the far side is the far end of the finger. Conversely, if a finger is positioned above the near side and there is empty space above the far side, subtracting the near side from the far side will result in a smaller value (a negative value with a large absolute value). In this case, the near side is the far end of the finger. There are cases where the edge cannot be measured.

[0196] In the example shown in Figure 19, the fingertip is pointing away from the sensor (towards the side with the larger row number), the fingertip is close to the electrostatic sensor 150, and the palm is away from the electrostatic sensor 150. In this case, the capacitance on the palm side becomes small, and the difference with the surrounding space becomes small, so the edge on the palm side (near side) cannot be detected.

[0197] Then, the control device 160 combines the detection position shown in Figure 19(d) and the detection position shown in Figure 19(e) to determine the final position of the edge of the operating body 20, as shown in Figure 19(f).

[0198] In Figure 19(f), the electrostatic sensor electrode 151 labeled "E" is the electrostatic sensor electrode 151 detected by the control device 160 as the position of the edge of the operating body 20.

[0199] For example, in the example shown in Figure 19(d), the control device 160 detects the position of the electrostatic sensor electrode 151 in the 5th column from the left as the maximum value of the above difference for each row from the 3rd to the 6th row from the top, and detects the position of the electrostatic sensor electrode 151 in the 7th column from the left as the minimum value of the above difference, and detects the position of the right edge of the operating body 20.

[0200] Furthermore, for example, in the example shown in Figure 19(e), the control device 160 detects the position of the electrostatic sensor electrode 151 in the third row from the top for each of the fifth to seventh columns from the left as the position of the leading edge of the operating body 20, as this corresponds to the minimum value of the above difference.

[0201] As a result, in the example shown in Figure 19(f), two rows of longitudinally shaped edges extending in the front-to-back direction, which face each other, and one row of transversely shaped edges extending in the left-to-right direction, which connects the front ends of the two rows of longitudinally shaped edges, are detected as the edges of the operating body 20.

[0202] (An example of a method for detecting the edge of the operating body 20 (third example)) Figure 20 shows an example (third example) of a method for detecting the edge of the operating body 20 by the control device 160 provided in the input device 100 according to one embodiment. Figure 20 explains an example of determining the position of the edge of the operating body 20 by executing the flowchart shown in Figures 12 to 15 (in the case of vertical and horizontal calculations of the second derivative).

[0203] In the example shown in Figure 20, the electrostatic sensor 150 has 10 rows of electrostatic sensor electrodes 151 arranged horizontally and 10 rows of electrostatic sensor electrodes 151 arranged vertically, arranged in a grid pattern. Figure 20(a) shows the detected capacitance values ​​of each electrostatic sensor electrode 151.

[0204] For example, as shown in Figure 20(b), the control device 160 copies the capacitance value of the outer electrostatic sensor electrode 151 to the outside of the outer electrostatic sensor electrode 151.

[0205] Next, as shown in Figure 20(c), the control device 160 applies a second-order differential filter (vertical and horizontal) to each electrostatic sensor electrode 151, using the same calculation method as the four-neighbor Laplacian filter. This filter multiplies the capacitance value by four and subtracts the capacitance values ​​of the adjacent electrostatic sensor electrodes 151 above, to the left, right, and below. For example, 87 in the 6th column of the 8th row is multiplied by four, and 11, 72, 70, and 90 in the front, back, left, and right are subtracted to calculate 105.

[0206] Then, as shown in Figure 20(d), the control device 160 detects the position of the electrostatic sensor electrode 151 (the area enclosed by the frame in the figure) in Figure 20(c) where the calculated value is greater than or equal to a predetermined threshold (for example, a value greater than 1 / 3 of the maximum value), as the position of the edge of the operating body 20. The maximum value in Figure 20(c) is 105 in the 6th column of the 8th row, and the control device 160 detects a position greater than 35, which is 1 / 3 of that value, as the position of the edge of the operating body 20.

[0207] In Figure 20(d), the electrostatic sensor electrode 151 labeled "E" is the electrostatic sensor electrode 151 detected by the control device 160 as the position of the edge of the operating body 20.

[0208] For example, in the example shown in Figure 20(d), the control device 160 detects the electrostatic sensor electrodes 151 in the 3rd to 8th rows from the top in the 5th column from the left as the position of the left edge of the operating body 20.

[0209] Furthermore, in the example shown in Figure 20(d), the control device 160 detects the electrostatic sensor electrodes 151 in the 3rd to 9th rows from the top in the 7th column from the left as the position of the right edge of the operating body 20.

[0210] Furthermore, in the example shown in Figure 20(d), the control device 160 detects the electrostatic sensor electrodes 151 in the 5th to 7th columns from the left for the 3rd row from the top as the position of the leading edge of the operating body 20.

[0211] (An example of a method for detecting the edge of the operating body 20 (fourth example)) Figure 21 shows an example (fourth example) of a method for detecting the edge of the operating body 20 by the control device 160 provided in the input device 100 according to one embodiment. Figure 21 describes another example of determining the position of the edge of the operating body 20 by executing the flowcharts shown in Figures 12, 15, 16, and 17 (in the case of calculation of vertical, horizontal, and diagonal lines using the second derivative).

[0212] In the example shown in Figure 21, the electrostatic sensor 150 has 10 rows of electrostatic sensor electrodes 151 arranged horizontally and 10 rows of electrostatic sensor electrodes 151 arranged vertically, arranged in a grid pattern. Figure 21(a) shows the detected capacitance values ​​of each electrostatic sensor electrode 151.

[0213] For example, as shown in Figure 21(b), the control device 160 copies the capacitance value of the outer electrostatic sensor electrode 151 to the outside of the outer electrostatic sensor electrode 151.

[0214] Next, as shown in Figure 21(c), the control device 160 uses a second-order differential filter (vertical, horizontal, and diagonal) with the same calculation method as the eight-nearest neighbor Laplacian filter to multiply the capacitance value by eight and subtract the capacitance values ​​of the adjacent electrostatic sensor electrodes 151 (top left, top, top right, left, right, bottom left, bottom, and bottom right). For example, multiplying the value of 74 in the 8th row and 7th column by eight and subtracting 10, 8, 6, 85, 15, 93, 91, and 27 in the front, back, left, right, and diagonal directions yields 257.

[0215] Then, as shown in Figure 21(d), the control device 160 detects the position of the electrostatic sensor electrode 151 (the area enclosed by the frame in the figure) where the calculated value in Figure 21(c) is greater than or equal to a predetermined threshold (for example, a value greater than 0.3 times the maximum value), as the position of the edge of the operating body 20. The maximum value in Figure 21(c) is 257 in the 7th column of the 8th row, and the control device 160 detects a position greater than 85.7, which is 1 / 3 of that value, as the position of the edge of the operating body 20.

[0216] In Figure 21(d), the electrostatic sensor electrode 151 labeled "E" is the electrostatic sensor electrode 151 detected by the control device 160 as the position of the edge of the operating body 20.

[0217] For example, in the example shown in Figure 21(d), the control device 160 detects the electrostatic sensor electrodes 151 in the 3rd to 9th rows from the top in the 5th column from the left as the position of the left edge of the operating body 20.

[0218] Furthermore, in the example shown in Figure 21(d), the control device 160 detects the electrostatic sensor electrodes 151 in the 3rd to 9th rows from the top in the 7th column from the left as the position of the right edge of the operating body 20.

[0219] Furthermore, in the example shown in Figure 21(d), the control device 160 detects the electrostatic sensor electrodes 151 in the 5th to 7th columns from the left for the 3rd and 4th rows from the top as the position of the leading edge of the operating body 20.

[0220] Although one embodiment of the present invention has been described in detail above, the present invention is not limited to these embodiments, and various modifications or changes are possible within the scope of the gist of the present invention as described in the claims.

[0221] This international application claims priority based on Japanese Patent Application No. 2025-029085, filed on 26 February 2025, and the entire contents of said application are incorporated herein by reference.

[0222] 10 Aerial image 20 Operating body 100 Input device 110 Housing 120 Light source 130 Beam splitter 140 Retroreflective member 150 Electrostatic sensor 151 Electrostatic sensor electrode 160 Control device

Claims

1. An input device comprising: a plurality of electrostatic sensor electrodes for detecting capacitance values ​​between itself and an operating object present in space; and a control device for detecting the position of the operating object in space based on the capacitance values ​​detected by the plurality of electrostatic sensor electrodes, wherein the control device calculates the input position based on the maximum value of the difference in capacitance values ​​of adjacent electrostatic sensor electrodes.

2. The input device according to claim 1, characterized in that the control device calculates a first subtraction value for each combination of adjacent electrostatic sensor electrodes by subtracting the capacitance value of the other electrostatic sensor electrode from the capacitance value of one of the electrostatic sensor electrodes, and calculates the position of the one electrostatic sensor electrode in the combination that maximizes the first subtraction value as the input position.

3. The input device according to claim 1, further comprising display means capable of displaying a plurality of aerial images in the space, wherein the control device displays the aerial images on the other side of the input position, while not displaying the aerial images on one side of the plurality of aerial images.

4. The input device according to claim 3, wherein the display means comprises a light source, a beam splitter that reflects light emitted from the light source, a retroreflective member that reflects light reflected by the beam splitter, and a shutter provided between the light source and the beam splitter, the aerial image is displayed in space by the beam splitter transmitting the light reflected by the retroreflective member, and the control device controls the display and non-display of each of the plurality of aerial images by controlling the opening and closing state of the shutter.

5. The input device according to claim 3, wherein the display means comprises a light source, a beam splitter that reflects light emitted from the light source, and a retroreflective member that reflects the light reflected by the beam splitter, the aerial image is displayed in space by the beam splitter transmitting the light reflected by the retroreflective member, and the control device controls the display and non-display of each of the plurality of aerial images by controlling the lighting state of the light source.

6. The input device according to claim 5, further comprising a display means capable of displaying multiple aerial images, wherein the control device calculates a first subtraction value for each combination of adjacent electrostatic sensor electrodes by subtracting the capacitance value of one electrostatic sensor electrode from the capacitance value of the other electrostatic sensor electrode, considers the position of one electrostatic sensor electrode in the combination that maximizes the first subtraction value as the other end, considers the position of the other electrostatic sensor electrode in the combination that minimizes the first subtraction value as the one end, and displays aerial images at other positions instead of displaying the aerial image between the one end and the other end.

7. The electrostatic sensor electrodes are arranged in a grid pattern in the vertical and horizontal directions, and the control device calculates a first subtraction value for each combination of horizontally adjacent electrostatic sensor electrodes by subtracting the capacitance value of one electrostatic sensor electrode from the capacitance value of the other electrostatic sensor electrode, calculates the position of one electrostatic sensor electrode in the combination of electrostatic sensor electrodes that maximizes the first subtraction value as the first edge position, calculates the position of the other electrostatic sensor electrode in the combination of electrostatic sensor electrodes that minimizes the first subtraction value as the second edge position, calculates a second subtraction value for each vertically adjacent combination of electrostatic sensor electrodes by subtracting the capacitance value of one electrostatic sensor electrode from the capacitance value of the other electrostatic sensor electrode, calculates the position of one electrostatic sensor electrode in the combination of electrostatic sensor electrodes that maximizes the second subtraction value as the third edge position, The input device according to claim 1, characterized in that the position of the other electrostatic sensor electrode in the combination of electrostatic sensor electrodes that minimizes the second subtraction value is calculated as the position of the fourth edge.

8. The input device according to claim 1, characterized in that the control device calculates a third subtraction value by multiplying the capacitance value of the electrostatic sensor electrode to be calculated by a predetermined coefficient, and then subtracting the capacitance values ​​of a plurality of electrostatic sensor electrodes adjacent to the electrostatic sensor electrode to be calculated, and the position where the value is greater than the value obtained by multiplying the maximum value of the third subtraction value by a predetermined coefficient is calculated as the edge position.

9. The input device according to claim 8, characterized in that the control device calculates the third subtracted value by multiplying the capacitance value of the electrostatic sensor electrode to be calculated by 2 as a predetermined coefficient, and then subtracting the capacitance values ​​of the two electrostatic sensor electrodes adjacent to the left and right of the electrostatic sensor electrode to be calculated.

10. The input device according to claim 8, characterized in that the control device calculates the third subtracted value by multiplying the capacitance value of the electrostatic sensor electrode to be calculated by 4 as a predetermined coefficient, and then subtracting the capacitance values ​​of the four electrostatic sensor electrodes adjacent to the electrostatic sensor electrode to be calculated in the front, back, left, and right directions.

11. The input device according to claim 8, characterized in that the control device calculates the third subtracted value by multiplying the capacitance value of the electrostatic sensor electrode to be calculated by 8 as a predetermined coefficient, and then subtracting the capacitance values ​​of eight electrostatic sensor electrodes adjacent to the electrostatic sensor electrode to be calculated in the front, back, left, right, and diagonally.

12. The input device according to claim 6, wherein the display means comprises a light source, a beam splitter that reflects light emitted from the light source, a retroreflective member that reflects light reflected by the beam splitter, and a shutter provided between the light source and the beam splitter, the beam splitter transmits the light reflected by the retroreflective member to display an aerial image in the space, and the control device controls the opening and closing state of the shutter to hide the light source corresponding to the area enclosed by the edge of the operating body with the shutter, thereby hiding the aerial image that overlaps with the area enclosed by the edge of the operating body.

13. An input device according to claim 6, comprising a light source, a beam splitter that reflects light emitted from the light source, and a retroreflective member that reflects light reflected by the beam splitter, wherein the light reflected by the retroreflective member is transmitted through the beam splitter to display the aerial image in space, and the control device turns off the light source corresponding to the area enclosed by the edge of the operating body, thereby hiding the aerial image that overlaps with the area enclosed by the edge.

14. The input device according to claim 12 or 13, characterized in that the control device detects two rows of edges facing each other and one row of edges connecting the ends of the two rows of edges, and outputs the central position in the one row of edges as the input position.

15. The input device according to claim 10 or 11, characterized in that the control device detects two rows of longitudinal edges facing each other and one row of transverse edges connecting the ends of the two rows of longitudinal edges, and outputs the central position of the transverse edge row as the input position.

16. An input device comprising: a plurality of electrostatic sensor electrodes for detecting capacitance values ​​between itself and an operating object present in space; a control device for detecting the position of the operating object in space based on the capacitance values ​​detected by the plurality of electrostatic sensor electrodes; and a display means capable of displaying a plurality of aerial images in space, wherein the control device detects the position of one edge of the operating object, outputs the position of one edge of the operating object as an input position, displays the aerial image on one side of the position of one edge of the operating object, and does not display the aerial image on the other side of the position of one edge of the operating object.

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