Detection device and detection method

Abstract

To provide a detection apparatus and a detection method which can discriminate a peak resulting from an object in its non-contact state having weak signal intensity.SOLUTION: A detection apparatus according to the present invention has a sensor part having a drive electrode and a plurality of detection electrodes and a control unit for detecting, by application to a voltage to the drive electrode, an object in its non-contact state from a signal waveform indicating time change of a signal intensity acquired by the detection electrode. The control unit discriminates a peak resulting from the object in its non-contact state based on a time width ΔT1 in a period from a peak rising start point to a peak top, a height ΔH1 from the peak rising start point to the peak top, and an inclination Uc on a peak rising side.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to a detection device and a detection method. [Background technology]

[0002] There is a demand for an interface that accepts user instructions through user gestures. For example, Patent Document 1 discloses a switch actuation device having a gesture sensor configured to output, for each pixel that detects heat when a translational gesture is performed, a signal having a signal fluctuation corresponding to the temporal transition of the detected heat intensity. Patent Document 1 distinguishes between a signal caused by a translational gesture and a noise signal by checking whether the absolute value of the signal fluctuation exceeds a predetermined level. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2016-526213 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, a signal caused by a gesture and a noise signal are distinguished only by the absolute value of the signal fluctuation, so when the level of the signal caused by the gesture is small (when the distance between the sensor and the gesture is far), it is difficult to distinguish between the signal caused by the gesture and the noise signal.

[0005] The present disclosure has been made in consideration of the above circumstances, and aims to provide a detection device and a detection method that can distinguish peaks resulting from a non-contact object with low signal strength. [Means for solving the problem]

[0006] In order to achieve the above object, a detection device according to a first aspect of the present disclosure includes: a sensor unit having a drive electrode and a plurality of detection electrodes; a control unit that applies a voltage to the drive electrode and detects a non-contact object from a signal waveform that indicates a time change in signal intensity obtained from the detection electrode, The control unit determining a first-order differential waveform and a second-order differential waveform of the signal waveform; the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is a positive value is taken as the time corresponding to the rising start point of the peak in the signal waveform, and the first time when the value of the first-order differential waveform changes from a positive value to a negative value in the direction in which time elapses from the time corresponding to the rising start point of the peak is taken as the time corresponding to the peak top of the peak, thereby distinguishing the rising start point of the peak and the peak top of the peak; The aforementioned The time span from the start of the rise of a peak to the peak top of said peak is equal to or greater than a predetermined first threshold, The height from the rising start point of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold, The slope of the rising side of the peak is equal to or greater than a predetermined third threshold. , the peak due to the non-contact object and Determine. A detection device according to a second aspect of the present disclosure includes: a sensor unit having a drive electrode and a plurality of detection electrodes; a control unit that applies a voltage to the drive electrode and detects a non-contact object from a signal waveform that indicates a time change in signal intensity obtained from the detection electrode, The control unit determining a first differential waveform and a second differential waveform of the moving averaged signal waveform; the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is a positive value is taken as the time corresponding to the rising start point of the peak in the moving-averaged signal waveform, and the first time when the value of the first-order differential waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the rising start point of the peak is taken as the time corresponding to the peak top of the peak, thereby distinguishing the rising start point of the peak and the peak top of the peak; If the time width from the start point of the peak's rise to its peak top is equal to or greater than a predetermined first threshold, the height from the start point of the peak's rise to its peak top is equal to or greater than a predetermined second threshold, and the slope of the rising side of the peak is equal to or greater than a predetermined third threshold, the peak is determined to be a peak caused by the object in the non-contact state.

[0007] The present disclosure 3 The detection method according to the aspect of applying a voltage to the drive electrodes to obtain signal waveforms from the plurality of detection electrodes, the signal waveforms indicating time-dependent changes in signal intensity; determining a first-order differential waveform and a second-order differential waveform of the signal waveform; determining the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is a positive value as the time corresponding to the start of the rise of the peak in the signal waveform, and determining the first time when the value of the first-order differential waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the start of the rise of the peak as the time corresponding to the peak top of the peak; and The aforementioned The time span from the start of the rise of a peak to the peak top of said peak is equal to or greater than a predetermined first threshold, The height from the rising start point of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold, The slope of the rising side of the peak is equal to or greater than a predetermined third threshold. , the peak due to the non-contact object and A determining step; and detecting the non-contact object based on the peak determined to be caused by the non-contact object. A detection method according to a fourth aspect of the present disclosure includes: applying a voltage to the drive electrodes to obtain signal waveforms from the plurality of detection electrodes, the signal waveforms indicating time-dependent changes in signal intensity; a step of performing a moving average process on the signal waveform to obtain the moving averaged signal waveform; determining a first-order differential waveform and a second-order differential waveform of the moving-averaged signal waveform; a step of determining the time when the value of the second derivative waveform changes from a positive value to a negative value and the value of the first derivative waveform is a positive value as the time corresponding to the rising start point of the peak in the moving-averaged signal waveform, and determining the first time when the value of the first derivative waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the rising start point of the peak and the peak top of the peak, thereby determining the rising start point of the peak and the peak top of the peak; a step of determining that the peak is caused by a non-contact object when the time width from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined first threshold, the height from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold, and the slope of the rising side of the peak is equal to or greater than a predetermined third threshold; and detecting the non-contact object based on the peak determined to be caused by the non-contact object. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to distinguish peaks resulting from a non-contact object with low signal strength. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram showing a detection device according to a first embodiment. [Figure 2] FIG. 2 is a plan view showing a sensor unit according to the first embodiment. [Figure 3] FIG. 2 is a schematic diagram showing a display unit according to the first embodiment. [Figure 4] FIG. 2 is a block diagram showing the configuration of a control unit according to the first embodiment. [Figure 5] FIG. 4 is a diagram showing a moving averaged signal waveform according to the first embodiment. [Figure 6] FIG. 3 is a diagram showing a first derivative waveform according to the first embodiment. [Figure 7] FIG. 3 is a diagram showing a second derivative waveform according to the first embodiment. [Figure 8] 4 is a diagram showing the rising start point and peak top of a signal waveform subjected to moving averaging according to the first embodiment. FIG. [Figure 9] FIG. 2 is a diagram illustrating a hardware configuration of a control unit according to the first embodiment. [Figure 10] 4 is a flowchart showing a detection process according to the first embodiment. [Figure 11] 1 is a flowchart showing a calculation process according to the first embodiment. [Figure 12] 1 is a flowchart showing a peak end point / peak top discrimination process according to the first embodiment. [Figure 13] 4 is a flowchart showing a peak discrimination process according to the first embodiment. [Figure 14] FIG. 3 is a diagram showing an example of a peak of an object according to the first embodiment. [Figure 15] 5 is a flowchart showing a non-contact detection process according to the first embodiment. [Figure 16] FIG. 3 is a diagram illustrating an example of a lookup table according to the first embodiment. [Figure 17] FIG. 10 is a diagram showing the end point of a decline in a moving-averaged signal waveform according to the second embodiment. [Figure 18] 10 is a flowchart showing a peak end point / peak top discrimination process according to the second embodiment. [Figure 19] FIG. 10 is a schematic diagram showing a virtual detection electrode according to a third embodiment. [Figure 20] FIG. 11 is a diagram showing an example of the time order of peak tops corresponding to a flick gesture from the +Y direction to the −Y direction according to the third embodiment. [Figure 21] FIG. 10 is a diagram showing a moving averaged signal waveform according to the third embodiment. [Figure 22] FIG. 11 is a diagram showing a moving averaged average signal waveform according to the third embodiment. [Figure 23] FIG. 10 is a schematic diagram showing a clockwise circle gesture according to a fourth embodiment. [Figure 24] 10 is a flowchart showing a non-contact detection process according to the fourth embodiment. [Figure 25] FIG. 10 is a diagram showing the end point of a downward trend in a moving-averaged signal waveform according to a modified example. [Figure 26] FIG. 10 is a schematic diagram showing a virtual detection electrode according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, a detection device according to an embodiment will be described with reference to the drawings.

[0011] <Embodiment 1> A detection device 10 according to this embodiment will be described with reference to Fig. 1 to Fig. 16. The detection device 10 detects a non-contact object (for example, a user's gesture). First, the overall configuration of the detection device 10 will be described.

[0012] As shown in FIG. 1, the detection device 10 includes a sensor unit 20 and a control unit 50. As shown in FIG. 2, the sensor unit 20 includes a light-transmitting substrate 22, a driving electrode 24, and a plurality of detection electrodes 26a-26e. The driving electrode 24 and the detection electrodes 26a-26e are formed on the light-transmitting substrate 22. The control unit 50 applies a voltage to the driving electrode 24, and detects a non-contact object from a signal waveform indicating a time change in the signal strength of a signal representing capacitance, which is acquired from the detection electrodes 26a-26e. For ease of understanding, the present specification will refer to the rightward direction (rightward on the paper) of the sensor unit 20 in FIG. 2 as the +X direction, the upward direction (upward on the paper) as the +Y direction, and the direction perpendicular to the +X and +Y directions (toward the viewer on the paper) as the +Z direction. Furthermore, a signal representing capacitance will also be referred to as a "signal," and the signal strength of a signal representing capacitance will also be referred to as a "signal strength."

[0013] As shown in FIG. 3 , the detection device 10 constitutes a display unit 200 together with the display device 100. The display unit 200 is mounted on a smartphone, a laptop computer, an information display, or the like. The display device 100 has a display panel 110 and a display control unit 120. The display panel 110 displays characters, images, and the like. The display panel 110 is a liquid crystal display panel, an organic EL (Electro Luminescence) display panel, or the like. The display control unit 120 controls the display of the display panel 110. The display control unit 120 and the control unit 50 of the detection device 10 are also connected to each other.

[0014] The sensor unit 20 of the detection device 10 is provided on the display surface side of the display panel 110 via an adhesive layer (not shown). In this case, the drive electrode 24 of the sensor unit 20 is located above the display area of ​​the display panel 110, and the detection electrodes 26a to 26e of the sensor unit 20 are located on the periphery of the display area of ​​the display panel 110. In addition, a resin protective cover 202 is provided on the sensor unit 20 via an adhesive layer (not shown). The detection device 10 detects a non-contact object located in a detection space above the sensor unit 20. In this way, the detection device 10 functions as an interface that accepts user instructions regarding the display of the display device 100. The thickness L of the detection space is, for example, 150 mm.

[0015] Next, a specific configuration of the detection device 10 will be described. As shown in Fig. 2, the sensor section 20 of the detection device 10 has a light-transmitting substrate 22, a driving electrode 24, and detection electrodes 26a to 26e.

[0016] The light-transmitting substrate 22 of the sensor unit 20 is, for example, a glass substrate. The light-transmitting substrate 22 has a first main surface 22a.

[0017] The driving electrode 24 of the sensor unit 20 is provided on the first main surface 22a of the light-transmitting substrate 22. The driving electrode 24 is rectangular and provided in the center of the first main surface 22a. In this embodiment, the driving electrode 24 covers the display area of ​​the display panel 110 in a plan view. The driving electrode 24 is electrically connected to the control unit 50 via wiring (not shown).

[0018] The detection electrodes 26a to 26e of the sensor unit 20 are each provided on a first main surface 22a of the light-transmitting substrate 22. The detection electrode 26a is disposed on the +Y side of the drive electrode 24 and extends in the X direction. The detection electrodes 26b to 26e are disposed side by side in the X direction on the -Y side of the drive electrode 24. Each of the detection electrodes 26a to 26e is electrically connected to the control unit 50 via wiring (not shown).

[0019] The driving electrode 24 and the detection electrodes 26a to 26e are made of, for example, ITO (Indium Tin Oxide), and form electrostatic capacitance between the driving electrode 24 and the detection electrodes 26a to 26e and an object (for example, a user's finger, hand, pen, etc.).

[0020] The control unit 50 of the detection device 10 detects a non-contact object from a signal waveform that indicates a time change in signal strength of a signal representing capacitance acquired from the detection electrodes 26a to 26e. First, the functional configuration of the control unit 50 will be described. As shown in FIG. 4, the control unit 50 includes an input / output unit 51, a storage unit 52, a drive unit 54, a receiving unit 56, a calculation unit 58, a first discrimination unit 62, a second discrimination unit 64, and a detection unit 66.

[0021] The input / output unit 51 of the control unit 50 inputs and outputs signals between the control unit 50 and the display control unit 120 of the display device 100, signals between the detection unit 66 and the control unit of the electronic device, and the like.

[0022] The storage unit 52 of the control unit 50 stores programs, data, a signal representing the capacitance received by the receiving unit 56, a signal waveform representing the change in signal strength over time, and the like.

[0023] A driving unit 54 of the control unit 50 applies a voltage to the driving electrode 24 based on an instruction from the control unit of the electronic device transmitted via the input / output unit 51. A receiving unit 56 of the control unit 50 receives a signal representing the capacitance from the detection electrodes 26a to 26e.

[0024] The calculation unit 58 of the control unit 50 performs moving average processing on the signal waveform, which indicates the time variation of the signal strength of the signal received by the receiving unit 56, to obtain a moving averaged signal waveform (FIG. 5). This makes it possible to remove small noise. Furthermore, the calculation unit 58 obtains the first-order differential waveform and the second-order differential waveform of the moving averaged signal waveform, as shown in FIGS. 6 and 7.

[0025] The first discrimination unit 62 of the control unit 50 discriminates the rising start point of the peak and the peak top of the peak in the moving-averaged signal waveform based on the first-order differential waveform and the second-order differential waveform of the moving-averaged signal waveform. Specifically, as shown in FIGS. 6 and 7, the first discrimination unit 62 determines the time at which the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform remains positive as the rising start point of the peak. The first discrimination unit 62 also determines the time at which the value of the first-order differential waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the rising start point of the peak as the peak top of the peak. Furthermore, the first discrimination unit 62 discriminates the rising start point of the peak and the peak top of the peak from the time corresponding to the rising start point of the peak and the time corresponding to the peak top of the peak. Hereinafter, the rising start point of the peak will also be referred to as the "rising start point," and the peak top of the peak will also be referred to as the "peak top."

[0026] In addition, if the peak top is not identified even after a predetermined first period (e.g., 100 ms) has elapsed since the time corresponding to the start of the rise (i.e., the time corresponding to the start of the rise and the time corresponding to the peak top are not within the predetermined first period), the first discrimination unit 62 may re-discriminate the point that was once identified as the start of the rise as not being the start of the rise, and may re-discriminate the start of the rise in the direction of time passage.

[0027] The second discrimination unit 64 of the control unit 50 discriminates peaks in the moving-averaged signal waveform that are attributable to a non-contact object based on the time width ΔT1 from the start point of the rise to the peak top, the height ΔH1 from the start point of the rise to the peak top, and the slope Uc on the rising side of the peak (Uc = ΔH1 / ΔT1). Specifically, the second discrimination unit 64 discriminates peaks in the moving-averaged signal waveform that are attributable to a non-contact object when the time width ΔT1 is equal to or greater than a predetermined first threshold Cw (e.g., 10 ms), the height ΔH1 is equal to or greater than a predetermined second threshold Ch (e.g., 10 a.u.), and the slope Uc on the rising side is equal to or greater than a third threshold Cd (e.g., 0.15). Hereinafter, peaks attributable to a non-contact object will also be referred to as "peaks of the object."

[0028] In this embodiment, the peak of an object is identified based on the time duration ΔT1, the height ΔH1, and the gradient Uc of the rising side. Therefore, the detection device 10 can identify the peak of an object even if the second threshold Ch, which is the threshold for the height ΔH1, is set to a small value. In other words, the detection device 10 can identify the peak of an object with a low signal strength. Furthermore, since the peak of an object is identified from the rising start point and the peak top, the peak of the object can be identified when the signal waveform reaches the peak top, and a non-contact object can be detected in a short time.

[0029] The detection unit 66 of the control unit 50 detects the movement of the non-contact object from the time order of the peak tops of the peaks of the object in the moving-averaged signal waveform of the detection electrodes 26a to 26e. For example, if the peak tops of the object peaks appear in the order of detection electrode 26e located on the +X side, detection electrode 26d, detection electrode 26c, and detection electrode 26b in the direction of time elapse, the detection unit 66 determines that the user has performed a flick gesture from the +X direction to the -X direction, and detects the user's flick gesture from the +X direction to the -X direction.

[0030] The detection unit 66 outputs a signal representing the detected movement of the non-contact object to a control unit of an electronic device incorporating the detection device 10. The signal representing the movement of the non-contact object represents, for example, a key event, a message, or the like set by the user for a flick gesture in the -X direction. The signal representing the detected movement of the non-contact object may be output once or multiple times for each detection. The detected gesture may be a flick gesture from the +Y direction to the -Y direction, a circle gesture in which the non-contact object moves in a circular motion, or the like. Hereinafter, the movement of the non-contact object will also be referred to as "movement of the object."

[0031] FIG. 9 shows the hardware configuration of the control unit 50. The control unit 50 is composed of a CPU (Central Processing Unit) 82, a ROM (Read Only Memory) 83, a RAM (Random Access Memory) 84, an input / output interface 86, and a specific function circuit 88. The CPU 82 executes a program stored in the ROM 83. The ROM 83 stores programs, data, signals, etc. The RAM 84 stores data. The input / output interface 86 inputs and outputs signals between each unit. The specific function circuit 88 includes a drive circuit, a receiving circuit, an arithmetic circuit, etc. The functions of the control unit 50 are realized by the execution of the program by the CPU 82 and the functions of the specific function circuit 88.

[0032] Next, the detection process (operation) of the detection device 10 will be described with reference to FIGS. 10 to 16. Here, a case will be described in which a display unit 200 having the detection device 10 and the display device 100 is mounted on an electronic device. As shown in FIG. 10, the detection process of the detection device 10 is performed in the following order: a drive process (step S100), a calculation process (step S200), a peak end point / peak top determination process (step S300), a peak determination process (step S400), and a non-contact detection process (step S500). After the non-contact detection process (step S500), if an end instruction is not input to the control unit 50 (step S600; NO), the detection process of the detection device 10 returns to the calculation process (step S200). If an end instruction is input to the control unit 50 (step S600; YES), the detection process of the detection device 10 ends.

[0033] In the driving process (step S100), based on an instruction from the control unit of the electronic device transmitted via input / output unit 51 of control unit 50, driving unit 54 of control unit 50 applies a voltage to driving electrode 24, and receiving unit 56 of control unit 50 receives signals representing the capacitance from each of detection electrodes 26a to 26e. The received signals representing the capacitance are stored in memory unit 52 of control unit 50.

[0034] The calculation process (step S200) will be described with reference to FIG. 11. In the calculation process (step S200), a moving-averaged signal waveform and a first-order differential waveform and a second-order differential waveform of the moving-averaged signal waveform are calculated. First, the calculation unit 58 of the control unit 50 performs moving averaging on a signal waveform indicating a time change in the signal strength of a signal received by the receiving unit 56, and calculates a moving-averaged signal waveform for each of the detection electrodes 26a to 26e (step S202). Furthermore, the calculation unit 58 calculates a first-order differential waveform and a second-order differential waveform of each of the calculated moving-averaged signal waveforms (step S204).

[0035] Next, the peak endpoint / peak top determination process (step S300) will be described with reference to FIG. 12. In the peak endpoint / peak top determination process (step S300), the rising start point and peak top of the moving-averaged signal waveform are determined based on the first-order and second-order differential waveforms of the moving-averaged signal waveform. First, the first determination unit 62 of the control unit 50 determines the rising start point of each moving-averaged signal waveform along the direction of time elapse from the first-order and second-order differential waveforms of the moving-averaged signal waveform (step S302). The first determination unit 62 determines the rising start point by determining the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is positive as the time corresponding to the rising start point. Step S302 is repeated along the direction of time elapse until the rising start point is determined (step S302; NO).

[0036] If the rise start point is determined (step S302; YES), the first discrimination unit 62 determines the peak top of each moving-averaged signal waveform from the first differential waveform of each moving-averaged signal waveform (step S304). The first discrimination unit 62 determines the peak top by determining the first time at which the value of the first differential waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the rise start point as the time corresponding to the peak top.

[0037] Step S304 is repeated in the direction of time elapse until the peak top is identified (step S304; NO). Note that if the peak top is not identified even after a predetermined first period (e.g., 100 ms) has elapsed since the time corresponding to the rise start point, that is, if the time corresponding to the rise start point and the time corresponding to the peak top are not within the predetermined first period, the rise start point identified in step S302 may be re-identified as not being the rise start point, and the process may return to step S302, where the rise start point may be identified again in the direction of time elapse.

[0038] If a peak top is identified (step S304; YES), the first discrimination unit 62 stores the time and moving average value corresponding to the identified start point of the rise and the time and moving average value corresponding to the identified peak top in the memory unit 52 (step S306), and the peak end point / peak top discrimination process (step S300) ends.

[0039] The peak discrimination process (step S400) will be described with reference to FIGS. 13 and 14. In the peak discrimination process (step S400), a peak of an object is discriminated in a moving-averaged signal waveform based on the time width ΔT1 from the start of the rise to the peak top, the height ΔH1 from the start of the rise to the peak top, and the slope Uc on the rising side of the peak. First, the second discrimination unit 64 of the control unit 50 determines the time width ΔT1 (the difference between the time corresponding to the peak top and the time corresponding to the start of the rise) and the height ΔH1 (the difference between the moving average value of the peak top and the moving average value of the start of the rise) between the start of the rise and the peak discriminated in the peak end point / peak top discrimination process (step S300) (step S402). Furthermore, the second discrimination unit 64 determines the slope Uc (ΔH1 / ΔT1) on the rising side of the peak (step S404).

[0040] Next, the second discrimination unit 64 determines whether the peak is a peak of an object in the moving-averaged signal waveform based on the time width ΔT1, the height ΔH1, and the ascending slope Uc of the peak (step S406). Specifically, as shown in Fig. 14, the second discrimination unit 64 determines that a peak whose time width ΔT1 is equal to or greater than a predetermined first threshold Cw, whose height ΔH1 is equal to or greater than a predetermined second threshold Ch, and whose ascending slope Uc is equal to or greater than a third threshold Cd is a peak of an object in the moving-averaged signal waveform. Note that a peak whose time width ΔT1 is less than the predetermined first threshold Cw, whose height ΔH1 is less than the predetermined second threshold Ch, and whose ascending slope Uc is less than the third threshold Cd is noise (noise peak).

[0041] If it is not determined to be a peak of the object (step S406; NO), the detection process returns to step S302 of the peak end point / peak top determination process (step S300). If it is determined to be a peak of the object (step S406; YES), the peak determination process (step S400) ends.

[0042] In this embodiment, the peak of the object is identified based on the time duration ΔT1, the height ΔH1, and the gradient Uc of the ascending side. Therefore, the peak identification process (step S400) can identify the peak of the object even if the second threshold Ch, which is the threshold value of the height ΔH1, is small. In other words, the detection process can identify the peak of an object with a low signal strength. Furthermore, the peak identification process (step S400) identifies the peak of the object from the ascending start point and the peak top, so the peak of the object can be identified when the signal waveform reaches the peak top, and a non-contact object can be detected in a short time.

[0043] The non-contact detection process (step S500) will be described with reference to FIGS. 15 and 16. In the non-contact detection process (step S500), the movement of the object (user's gesture) is determined from the time order of the peak tops of the identified peaks of the object. First, the detection unit 66 of the control unit 50 arranges the detection electrodes 26a to 26e in the time order of the peak tops of their respective moving-averaged signal waveforms (step S502). Then, the detection unit 66 determines the movement of the object (user's gesture) by referring to a lookup table that indicates the relationship between the time order of the peak tops of the moving-averaged signal waveforms of the detection electrodes 26a to 26e and the movement of the object (step S504). FIG. 16 shows an example of the lookup table. For example, if the time order of the peak tops is detection electrode 26e, detection electrode 26d, detection electrode 26c, and detection electrode 26b, the detection unit 66 determines that the user has performed a flick gesture from the +X direction to the −X direction, and detects a flick gesture from the +X direction to the −X direction. The lookup table is stored in advance in the storage unit 52.

[0044] If the movement of the object is detected (step S504; YES), the detection unit 66 outputs a signal representing the detected movement of the object to the control unit of the electronic device in which the display unit 200 (detection device 10) is mounted via the input / output unit 51 (step 506). When the detection unit 66 outputs the signal representing the movement of the object, the non-contact detection process (step S500) ends. If the movement of the object is not detected (step S506; NO), the detection process returns to step S302 of the peak endpoint / peak top discrimination process (step S300).

[0045] As described above, the detection device 10 identifies the peak of an object based on the time duration ΔT1, the height ΔH1, and the ascending slope Uc, and can therefore identify peaks of objects with low signal strength. Furthermore, the detection device 10 identifies the peak of an object from the ascending start point and the peak top, and can therefore detect non-contact objects in a short time.

[0046] <Embodiment 2> In the first embodiment, the detection device 10 distinguishes the start point of the ascent of the peak and the peak top of the peak. The detection device 10 may distinguish the start point of the ascent of the peak, the peak top of the peak, and the end point of the descent of the peak. Hereinafter, the end point of the descent of the peak will also be referred to as the "end point of descent."

[0047] The detection device 10 of this embodiment includes a sensor unit 20 and a control unit 50, similar to the detection device 10 of embodiment 1. Since the sensor unit 20 of this embodiment is similar to the sensor unit 20 of embodiment 1, the control unit 50 and detection processing of this embodiment will be described here.

[0048] The control unit 50 of this embodiment includes an input / output unit 51 to a detection unit 66, similar to the control unit 50 of embodiment 1. The input / output unit 51 to a calculation unit 58, the second discrimination unit 64, and the detection unit 66 of this embodiment are the same as those of embodiment 1, so only the first discrimination unit 62 of this embodiment will be described.

[0049] The first discrimination unit 62 of this embodiment discriminates the start point of an ascent, the peak top, and the end point of a descent in the moving-averaged signal waveform based on the first-order differential waveform and the second-order differential waveform of the moving-averaged signal waveform. The discrimination of the start point of an ascent and the peak top is the same as in embodiment 1. As shown in Figures 6, 7, and 17, the first discrimination unit 62 of this embodiment determines the end point of a descent by determining the time at which the value of the second-order differential waveform changes from a negative value to a positive value and the value of the first-order differential waveform is negative in the direction of time elapse from the time corresponding to the peak top as the time corresponding to the end point of a descent.

[0050] Furthermore, in this embodiment, if the end point of the descent is not identified even after a predetermined second period (e.g., 30 ms) has elapsed since the time corresponding to the peak top (i.e., the time corresponding to the peak top at the start of the rise and the time corresponding to the end point of the descent are not within the predetermined second period), the first discrimination unit 62 re-discriminates the points previously identified as the start point of the rise and the points previously identified as the peak top as not being the start point of the rise and the peak top, and re-discriminates the start point of the rise in the direction in which time passes.

[0051] Next, the detection process of this embodiment will be described. Similar to the detection process of embodiment 1, the detection process of this embodiment is performed in the order of drive process (step S100) to non-contact detection process (step S500). Since the drive process (step S100), peak discrimination process (step S400), and non-contact detection process (step S500) of this embodiment are the same as those of embodiment 1, the peak end point / peak top discrimination process (step S300) of this embodiment will be described with reference to FIG. 18.

[0052] First, similarly to the peak end point / peak top determination process (step S300) of the first embodiment, the first determination unit 62 of the control unit 50 determines the start point of the ascent (step S302) and determines the peak top (step S304). If the peak top is determined (step S304; YES), the first determination unit 62 determines the end point of the descent in each of the moving-averaged signal waveforms from the first-order differential waveform and the second-order differential waveform of each of the moving-averaged signal waveforms (step S306).

[0053] Specifically, the first discrimination unit 62 determines the end point of the decline by determining the time corresponding to the decline end point as the time when the value of the second derivative waveform changes from a negative value to a positive value and the value of the first derivative waveform is negative in the direction of time elapse from the time corresponding to the peak top. If the peak top is not determined even after a predetermined second period has elapsed from the time corresponding to the peak top (step S306; NO), the ascent start point determined in step S302 and the peak top determined in step S304 are re-determined as not being the ascent start point and not being a peak top, respectively, and the peak end point / peak top discrimination process (step S300) returns to step S302.

[0054] If the peak top is identified within a predetermined second period from the time corresponding to the peak top (step S306; YES), the first discrimination unit 62 stores the time and moving average value corresponding to the identified start point of the rise, and the time and moving average value corresponding to the identified peak top in the memory unit 52 (step S306), and the peak endpoint / peak top discrimination process (step S300) ends.

[0055] In this embodiment, the start point of the rise and the peak top (i.e., the presence or absence of a peak) are determined based on whether the end point of the fall is within a predetermined second period from the time corresponding to the peak top. This allows the detection device 10 of this embodiment to suppress the discrimination of an increase in signal strength that is not due to the movement of an object as a peak, thereby suppressing erroneous detection. Furthermore, like the detection device 10 of embodiment 1, the detection device 10 of this embodiment can discriminate peaks of objects with low signal strength.

[0056] <Embodiment 3> In the first and second embodiments, the detection device 10 detects the movement of the object from the signal waveforms of the detection electrodes 26a to 26e. The detection device 10 may also detect the movement of the object from a signal waveform obtained by averaging the signal waveforms of multiple detection electrodes (for example, the detection electrodes 26b to 26e).

[0057] In this embodiment, the detection device 10 detects the movement of an object from a signal waveform obtained by averaging the signal waveforms of the detection electrodes 26a to 26e and the signal waveforms of the detection electrodes 26b to 26e. The detection device 10 of this embodiment includes a sensor unit 20 and a control unit 50, similar to the detection device 10 of embodiment 1. The sensor unit 20 of this embodiment is similar to the sensor unit 20 of embodiment 1, and therefore the control unit 50 and detection processing of this embodiment will be described here.

[0058] The control unit 50 of this embodiment includes an input / output unit 51 to a detection unit 66, similar to the control unit 50 of embodiment 1. The input / output unit 51 to the reception unit 56 of this embodiment are the same as those of embodiment 1, so only the calculation unit 58 to the detection unit 66 of this embodiment will be described.

[0059] The calculation unit 58 of this embodiment, like the calculation unit 58 of the first embodiment, obtains a moving average signal waveform of the detection electrodes 26a to 26e from the signal received by the receiving unit 56.

[0060] Furthermore, the calculation unit 58 of this embodiment sets a virtual detection electrode composed of a plurality of detection electrodes and obtains a moving-averaged signal waveform of the virtual detection electrode. In this embodiment, as shown in FIG. 19, a virtual detection electrode (26b-26e) is formed from detection electrodes 26b to 26e. The calculation unit 58 of this embodiment obtains an average signal waveform (26b-26e) by averaging the signal waveforms of the detection electrodes 26b to 26e as the signal waveform of the virtual detection electrode (26b-26e). Furthermore, the calculation unit 58 of this embodiment performs moving averaging on the average signal waveform (26b-26e) to obtain a moving-averaged average signal waveform (26b-26e).

[0061] Furthermore, the calculation unit 58 of this embodiment obtains the first and second differential waveforms of the moving-averaged signal waveforms of the detection electrodes 26a to 26e and the moving-averaged average signal waveform (26b-26e).

[0062] The first determination unit 62 of this embodiment determines the rising start point and the peak top in the moving-averaged signal waveform of the detection electrodes 26a to 26e and the moving-averaged average signal waveform (26b-26e) of the virtual detection electrode (26b-26e). The determination of the rising start point and the peak top is the same as in the first embodiment.

[0063] The second discrimination unit 64 of this embodiment discriminates the peaks of the object in the moving-averaged signal waveforms of the detection electrodes 26a to 26e and the moving-averaged average signal waveform (26b-26e) of the virtual detection electrode (26b-26e). The discrimination of the peaks of the object is the same as in the first embodiment.

[0064] The detection unit 66 of this embodiment determines the movement of the object from the time order of the peak tops of the object peaks in the moving-averaged signal waveforms of the detection electrodes 26a to 26e and the moving-averaged average signal waveform (26b-26e). For example, if the peak tops of the object peaks appear in the order of the detection electrode 26a and the virtual detection electrodes (26b-26e) in the direction of time passage, the detection unit 66 determines that the user has performed a flick gesture from the +Y direction to the -Y direction, and detects the user's flick gesture from the +Y direction to the -Y direction.

[0065] When determining whether a flick gesture is from the +Y direction to the −Y direction based solely on the time order of the peak tops of the detection electrodes 26a to 26e, there are many time orders of the peak tops corresponding to flick gestures from the +Y direction to the −Y direction, which may make the determination complicated, as shown in Fig. 20. In addition, as shown in Fig. 21, the signal strength difference and time difference of the peak tops may become small, which may make the determination difficult.

[0066] In this embodiment, when the peak tops appear in the order of detection electrode 26a and virtual detection electrodes (26b-26e), it is determined that the user has performed a flick gesture from the +Y direction to the -Y direction, so that the detection device 10 of this embodiment can easily determine the movement of the object. Also, as shown in Fig. 22, the number of signal waveforms to be determined is reduced, so that the detection device 10 of this embodiment can easily determine the movement of the object.

[0067] The detection unit 66 of this embodiment outputs a signal representing the detected movement of the object to a control unit of an electronic device equipped with the detection device 10. The signal representing the movement of the object represents, for example, a key event, a message, or the like set by the user for a flick gesture in the -Y direction. Note that the detection unit 66 of this embodiment may detect a flick gesture from the +Y direction to the -Y direction from the time order of the peak top of the detection electrode 26a, the peak top of the virtual detection electrodes (26b-26e), and the peak tops of the detection electrodes 26b to 26e.

[0068] Next, the detection process of this embodiment will be described. The detection process of this embodiment is performed in the order of drive process (step S100) to non-contact detection process (step S500), similar to the detection process of embodiment 1. Since the drive process (step S100) of this embodiment is the same as that of embodiment 1, the calculation process (step S200) to non-contact detection process (step S500) of this embodiment will be described.

[0069] In the calculation process (step S200) of this embodiment, the calculation unit 58 calculates an average signal waveform (26b-26e) by averaging the signal waveforms of the detection electrodes 26b to 26e as the signal waveform of the virtual detection electrode (26b-26e), and further calculates a moving-averaged average signal waveform (26b-26e). The calculation unit 58 calculates a first-order differential waveform and a second-order differential waveform of the moving-averaged average signal waveform (26b-26e). Other processes in the calculation process (step S200) of this embodiment are similar to those in the calculation process (step S200) of the first embodiment.

[0070] In the peak end point / peak top determination process (step S300) of this embodiment, the first determination unit 62 determines the rising start points and peak tops in the moving-averaged signal waveforms and the moving-averaged average signal waveforms (26b-26e) of the detection electrodes 26a-26e based on the calculated first-order differential waveforms and second-order differential waveforms. Other processes in the peak end point / peak top determination process (step S300) of this embodiment are the same as those in the peak end point / peak top determination process (step S300) of the first embodiment.

[0071] In the peak discrimination process (step S400) of this embodiment, the second discrimination unit 64 discriminates the peak of the object in the moving-averaged signal waveforms of the detection electrodes 26a-26e and the moving-averaged average signal waveform (26b-26e) based on the time width ΔT1 from the rise start point to the peak top, the height ΔH1 from the rise start point to the peak top, and the slope Uc on the rising side of the peak. The other processes in the peak discrimination process (step S400) of this embodiment are the same as those in the peak discrimination process (step S400) of the first embodiment.

[0072] In the non-contact detection process (step S500) of this embodiment, the detection unit 66 determines the movement of the object (user's gesture) from the time order of the peak tops of the identified peaks of the object. As in the first embodiment, the detection unit 66 determines the movement of the object by referring to a lookup table that indicates the relationship between the time order of the peak tops and the movement of the object.

[0073] As described above, the detection device 10 of this embodiment can easily detect an object because it determines the movement of the object from a signal waveform obtained by averaging the signal waveforms of the multiple detection electrodes (detection electrodes 26b to 26e). Furthermore, like the detection device 10 of the first embodiment, the detection device 10 of this embodiment can determine the peak of an object with low signal intensity.

[0074] <Embodiment 4> In the first to third embodiments, the detection device 10 determines the movement of the object from the time order of the peak tops. The detection device 10 may also determine the movement of the object from the time interval between the peak tops.

[0075] In this embodiment, the detection device 10 determines the movement of an object based on the time order of the peak tops and the time interval between the peak tops. Similar to the detection device 10 of embodiment 1, the detection device 10 of this embodiment includes a sensor unit 20 and a control unit 50. Since the sensor unit 20 of this embodiment is similar to the sensor unit 20 of embodiment 1, the control unit 50 and detection processing of this embodiment will be described here.

[0076] The control unit 50 of this embodiment includes an input / output unit 51 to a detection unit 66, similar to the control unit 50 of embodiment 3. The input / output unit 51 to the second determination unit 64 of this embodiment are the same as those of embodiment 3, so only the detection unit 66 of this embodiment will be described.

[0077] The detection unit 66 of this embodiment classifies the type of movement of the object to be distinguished (type of gesture to be distinguished) based on the time interval between the peak top of the detection electrodes 26a to 26e and the peak top of the virtual detection electrode (26b-26e). For example, the detection unit 66 classifies the type of movement of the object to be distinguished into a flick gesture and a circle gesture based on the time interval between the peak top of the moving-averaged signal waveform of the detection electrode 26a and the peak top of the moving-averaged average signal waveform (26b-26e) of the virtual detection electrode (26b-26e).

[0078] Specifically, when the time interval T2 between the peak top of the detection electrode 26a and the peak top of the virtual detection electrodes (26b-26e) is equal to or less than a predetermined fourth threshold th4, the detection unit 66 determines that the type of movement of the object to be distinguished is a flick gesture. Furthermore, when the time interval T2 between the peak top of the detection electrode 26a and the peak top of the virtual detection electrodes (26b-26e) is greater than the predetermined fourth threshold th4 and less than a predetermined fifth threshold th5, the detection unit 66 determines that the type of movement of the object to be distinguished is a circle gesture. Because the time from the start to the end of a flick gesture is shorter than the time from the start to the end of a circle gesture, the type of movement of the object to be distinguished can be divided into a flick gesture and a circle gesture based on the time interval between the peak tops.

[0079] The detection unit 66 of this embodiment further distinguishes the object's movement from the time order of the peak tops of the detection electrodes 26a to 26e and the virtual detection electrodes (26b-26e) for each type of object's movement to be distinguished. For example, if the type of object's movement to be distinguished is a circle gesture and the time order of the peak tops is the peak top of the detection electrode 26a followed by the peak tops of the virtual detection electrodes (26b-26e), the object's movement is distinguished as a clockwise circle gesture as shown in FIG. 23. On the other hand, if the type of object's movement to be distinguished is a circle gesture and the time order of the peak tops is not a preset time order, the object's movement is distinguished as not being an object's movement. Furthermore, if the type of object's movement to be distinguished is a flick gesture and the time order of the peak tops is the peak top of the detection electrode 26a followed by the peak tops of the virtual detection electrodes (26b-26e), the object's movement is distinguished as a flick gesture from the +Y direction to the -Y direction.

[0080] In this embodiment, the detection device 10 determines the movement of an object from the time order of the peak tops and the time interval between the peak tops, and therefore can more easily determine the movement of a wider variety of objects.

[0081] Next, the detection process of this embodiment will be described. The detection process of this embodiment is performed in the order of drive process (step S100) to non-contact detection process (step S500), similar to the detection process of embodiment 1. The drive process (step S100) to peak determination process (step S400) of this embodiment are the same as those of embodiment 3, so the non-contact detection process (step S500) of this embodiment will be described with reference to FIG. 24.

[0082] In the non-contact detection process (step S500) of the present embodiment, first, the detection unit 66 of the control unit 50 arranges the detection electrodes 26a to 26e and the virtual detection electrodes (26b - 26e) in the chronological order of the peak tops (step S512). Next, the detection unit 66 discriminates the type of movement of the object to be discriminated (the type of user gesture) from the time intervals between the peak tops of the detection electrodes 26a to 26e and the peak tops of the virtual detection electrodes (26b - 26e) (step S514). Specifically, when the time interval T2 between the peak top of the detection electrode 26a and the peak tops of the virtual detection electrodes (26b - 26e) is less than or equal to a predetermined fourth threshold value th4, the detection unit 66 sets the type of movement of the object to be discriminated as a flick gesture (step S514; T2 ≤ th4). When the time interval T2 between the peak top of the detection electrode 26a and the peak tops of the virtual detection electrodes (26b - 26e) is greater than the fourth threshold value th4 and less than a predetermined fifth threshold value th5, the detection unit 66 sets the type of movement of the object to be discriminated as a circle gesture (step S514; th4 < T2 < th5). Further, when the time interval T2 between the peak top of the detection electrode 26a and the peak tops of the virtual detection electrodes (26b - 26e) is equal to the predetermined fifth threshold value th5, the detection process returns to step S302 of the peak top discrimination process (step S300).

[0083] When the type of movement of the object to be discriminated is a flick gesture (step S514; T2 ≤ th4), the detection unit 66 detects the movement of the object by referring to a look-up table showing the relationship between the chronological order of the peak tops in the flick gesture and the movement of the object (step S516). When the movement of the object is not detected (step S514; NO), the detection process returns to step S302 of the peak endpoint · peak top discrimination process (step S300).

[0084] On the other hand, when the type of movement of the object to be discriminated is a circle gesture (step S514; th4 < T2 < th5), the detection unit 66 refers to a look-up table showing the relationship between the time order of the peak tops in the circle gesture and the movement of the object, and detects the movement of the object (step S518). If the movement of the object is not detected (step S518; NO), the detection process returns to step S302 of the peak endpoint / peak top discrimination process (step S300).

[0085] In step S516 or step S518, when the movement of the object is detected (step S516; YES, step S518; YES), the detection unit 66 outputs a signal representing the detected movement of the object to the control unit of the electronic device on which the display unit 200 (detection device 10) is mounted (step 506). When the detection unit 66 outputs a signal representing the movement of the object, the non-contact detection process (step S500) ends.

[0086] As described above, since the detection device 10 of the present embodiment discriminates the movement of the object from the time order of the peak tops and the time intervals between the peak tops, it is possible to more easily discriminate more types of movements of the object. Further, the detection device 10 of the present embodiment can discriminate the peaks of an object with a small signal intensity.

[0087] <Modification Example> Although the embodiment has been described above, the present disclosure can be variously modified without departing from the gist thereof.

[0088] For example, the number and arrangement of the detection electrodes of the sensor unit 20 are arbitrary. For example, the detection electrodes may also be arranged on the +X side and -X side of the drive electrode 24 and surround the drive electrode 24. Further, the sensor unit 20 may include a plurality of drive electrodes 24.

[0089] The detection device 10 may determine the peak of the object based on at least one of the time width ΔT3 from the end point of the descent to the peak top, the height ΔH2 from the end point of the descent to the peak top, and the slope Dc (ΔH2 / ΔT3) on the downward side of the peak, as shown in Figure 25, in addition to the time width ΔT1 from the start point of the rise to the peak top, the height ΔH1 from the start point of the rise to the peak top, and the slope Uc on the upward side of the peak.

[0090] In the embodiment, the detection device 10 performs moving average processing on the signal waveform indicating the time change of the signal strength. The detection device 10 does not have to perform moving average processing on the signal waveform indicating the time change of the signal strength. For example, the detection device 10 may determine the rising start point and the peak top based on the first-order differential waveform and the second-order differential waveform of the signal waveform received by the receiving unit 56.

[0091] In the third embodiment, the movement of the object is detected from a signal waveform obtained by averaging the signal waveforms of the detection electrodes 26b to 26e (average signal waveform (26b-26e) of the virtual detection electrodes (26b-26e)). The detection electrodes constituting the virtual detection electrodes are not limited to the detection electrodes 26b to 26e. For example, as shown in FIG. 26, the virtual detection electrodes may be composed of the detection electrodes 26a and 26b (virtual detection electrodes (26a, 26b)) and the detection electrodes 26a and 26e (virtual detection electrodes (26a, 26e)). For example, if the peak tops appear in the order of the virtual detection electrodes (26a, 26b), the detection electrode 26a, the virtual detection electrodes (26a, 26e), and the virtual detection electrodes (26b-26e), the detection device 10 can determine that the gesture is a clockwise circle gesture.

[0092] The control unit 50 may include dedicated hardware such as an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a control circuit. In this case, each process may be executed by separate hardware. Alternatively, each process may be executed collectively by a single piece of hardware. Some of the processes may be executed by dedicated hardware, and other parts of the processes may be executed by software or firmware.

[0093] Although the preferred embodiments have been described above, the present disclosure is not limited to such specific embodiments, and the present disclosure includes the inventions described in the claims and their equivalents. [Explanation of symbols]

[0094] 10 detection device, 20 sensor unit, 22 light-transmitting substrate, 22a first main surface, 24 drive electrode, 26a to 26e detection electrodes, 50 control unit, 51 input / output unit, 52 memory unit, 54 drive unit, 56 receiving unit, 58 calculation unit, 62 first discrimination unit, 64 second discrimination unit, 66 detection unit, 82 CPU, 83 ROM, 84 RAM, 86 input / output interface, 88 specific function circuit, 100 display device, 110 display panel, 120 display control unit, 200 display unit, 202 protective cover, L thickness, Cw first threshold, Ch second threshold, Cd third threshold, Uc rising slope, Dc falling slope, ΔH1 height, ΔT1 time width, T2 time interval, ΔT3 time width, th4 fourth threshold, th5 fifth threshold

Claims

1. a sensor unit having a drive electrode and a plurality of detection electrodes; a control unit that applies a voltage to the drive electrode and detects a non-contact object from a signal waveform that indicates a time change in signal intensity obtained from the detection electrode, The control unit determining a first-order differential waveform and a second-order differential waveform of the signal waveform; the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is a positive value is taken as the time corresponding to the rising start point of the peak in the signal waveform, and the first time when the value of the first-order differential waveform changes from a positive value to a negative value in the direction in which time elapses from the time corresponding to the rising start point of the peak is taken as the time corresponding to the peak top of the peak, thereby distinguishing the rising start point of the peak and the peak top of the peak; When the time width from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined first threshold value, the height from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold value, and the slope of the rising side of the peak is equal to or greater than a predetermined third threshold value, the peak is determined to be caused by the object in the non-contact state. Detection device.

2. a sensor unit having a drive electrode and a plurality of detection electrodes; a control unit that applies a voltage to the drive electrode and detects a non-contact object from a signal waveform that indicates a time change in signal intensity obtained from the detection electrode, The control unit determining a first differential waveform and a second differential waveform of the moving averaged signal waveform; the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is a positive value is taken as the time corresponding to the rising start point of the peak in the moving-averaged signal waveform, and the first time when the value of the first-order differential waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the rising start point of the peak is taken as the time corresponding to the peak top of the peak, thereby distinguishing the rising start point of the peak and the peak top of the peak; When the time width from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined first threshold value, the height from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold value, and the slope of the rising side of the peak is equal to or greater than a predetermined third threshold value, the peak is determined to be a peak caused by the object in the non-contact state. Detection device.

3. When the time corresponding to the ascent start point of the peak and the time corresponding to the peak top of the peak are not within a predetermined first period, the control unit determines the next ascent start point of the peak in the direction in which time elapses from the time corresponding to the ascent start point of the peak.

3. The detection device according to claim 1 or 2.

4. the control unit determines the first time, in the direction of time elapse from the time corresponding to the peak top of the peak, when the value of the second derivative waveform changes from a negative value to a positive value and the value of the first derivative waveform is a negative value, as the time corresponding to the end point of the decline of the peak, and if the time corresponding to the peak top of the peak and the time corresponding to the end point of the decline of the peak are not within a predetermined second period, determines the start point of the next rise of the peak in the direction of time elapse from the time corresponding to the peak top of the peak.

4. The detection device according to claim 1.

5. the control unit determines the peak caused by the object in the non-contact state based on at least one of a time width from a descent end point of the peak to a peak top of the peak, a height from a descent end point of the peak to a peak top of the peak, and a slope of the descent side of the peak. The detection device according to claim 4.

6. The control unit sets a virtual detection electrode formed from a plurality of the detection electrodes, the signal waveform is a waveform obtained by averaging a signal waveform indicating a time change in signal intensity acquired from each of the detection electrodes and a signal waveform indicating a time change in signal intensity acquired from each of the detection electrodes forming the virtual detection electrode; 6. A detection device according to any one of claims 1 to 5.

7. the control unit determines the movement of the non-contact object from the time order of the peak tops of the peaks determined to be caused by the non-contact object.

7. A detection device according to any one of claims 1 to 6.

8. the control unit determines the movement of the non-contact object from the time interval of the peak tops of the peaks determined to be caused by the non-contact object. The detection device according to claim 7.

9. applying a voltage to the drive electrodes to obtain signal waveforms from the plurality of detection electrodes, the signal waveforms indicating time-varying signal intensities; determining a first-order differential waveform and a second-order differential waveform of the signal waveform; determining the time when the value of the second-order differential waveform changes from a positive value to a negative value and the value of the first-order differential waveform is a positive value as the time corresponding to the start of the rise of the peak in the signal waveform, and determining the first time when the value of the first-order differential waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the start of the rise of the peak as the time corresponding to the peak top of the peak; and a step of determining that the peak is caused by a non-contact object when the time width from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined first threshold, the height from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold, and the slope of the rising side of the peak is equal to or greater than a predetermined third threshold; and detecting the non-contact object based on the peak attributable to the non-contact object that has been determined. Detection method.

10. applying a voltage to the drive electrodes to obtain signal waveforms from the plurality of detection electrodes, the signal waveforms indicating time-varying signal intensities; a step of performing a moving average process on the signal waveform to obtain the moving averaged signal waveform; determining a first-order differential waveform and a second-order differential waveform of the moving-averaged signal waveform; a step of determining the time when the value of the second derivative waveform changes from a positive value to a negative value and the value of the first derivative waveform is a positive value as the time corresponding to the rising start point of the peak in the moving-averaged signal waveform, and determining the first time when the value of the first derivative waveform changes from a positive value to a negative value in the direction of time elapse from the time corresponding to the rising start point of the peak and the peak top of the peak, thereby determining the rising start point of the peak and the peak top of the peak; a step of determining that the peak is caused by a non-contact object when the time width from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined first threshold, the height from the start point of the rise of the peak to the peak top of the peak is equal to or greater than a predetermined second threshold, and the slope of the rising side of the peak is equal to or greater than a predetermined third threshold; and detecting the non-contact object based on the peak attributable to the non-contact object that has been determined. Detection method.

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