Detection device and detection system

Abstract

To provide a detection device and a detection system capable of suppressing a deterioration in acquisition precision of proximity detection coordinates.SOLUTION: A detection device includes a sensor substrate, a plurality of electrodes provided in a detection area of the sensor substrate in a first direction and in a second direction different from the first direction, a detection circuit for generating a detection value in each electrode, and a processing circuit for generating spatial coordinates showing a position to be detected on the detection area. The processing circuit acquires first data Rx showing a position in the first direction, second data Ry showing a position in the second direction and third data Rz showing a position in a third direction perpendicular to the first and second directions on the basis of detection values S(n) of the plurality of electrodes, and generates spatial coordinates R (Rx, Ry, Rz) including the first data Rx, the second data Ry, and the third data Rz in the case where at least one of the detection values S(n) of each electrode is a first threshold Sth1 or more and is less than a second threshold Sth2 larger than the first threshold Sth1.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a detection device and a detection system.

Background Art

[0002] In recent years, a detection system in which a detection device capable of detecting an external proximity object, so-called a touch panel, is mounted or integrated on a display device such as a liquid crystal display device is known (see, for example, Patent Documents 1 to 3). In such a detection system, in addition to a touch detection function for detecting contact of a detection object such as an operator's finger with a detection surface, in a state where a finger is not touching the detection surface, the proximity state of a finger in the space on the detection area and gestures, etc. are detected. The hover detection function is attracting attention.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a configuration in which a plurality of electrodes are provided in a detection area, the capacitance generated in each electrode is detected, and the spatial coordinates of the position where the detection object exists on the detection area are detected, compared with a configuration for detecting the planar coordinates of the touch detection position, it is necessary to increase the sensitivity by increasing the size of each electrode. In such a configuration, if the distance between the detection surface and the detection object is too close, the detection signal may exceed the maximum value that can be detected by the detection circuit, and the acquisition accuracy of the detection coordinates may decrease.

[0005] An object of the present invention is to provide a detection device and a detection system capable of suppressing a decrease in the acquisition accuracy of proximity detection coordinates.

Means for Solving the Problems

[0006] A detection device according to an aspect of the present invention includes a sensor substrate, a plurality of electrodes arranged in a first direction and a second direction different from the first direction in a detection region of the sensor substrate, and a detection circuit that generates a detection value for each electrode based on detection signals output from the plurality of electrodes, and a processing circuit that generates spatial coordinates indicating the position of a detection object on the detection region, the spatial coordinates including first data indicating the position in the first direction, second data indicating the position in the second direction, and third data indicating the position in a third direction orthogonal to the first direction and the second direction, the processing circuit having a first threshold value set for the detection value and a second threshold value larger than the first threshold value, and when at least one of the detection values for each electrode is equal to or greater than the first threshold value and less than the second threshold value, acquiring the first data, the second data, and the third data based on the detection values of the plurality of electrodes, and generating spatial coordinates including the first data, the second data, and the third data.

[0007] A detection system according to an aspect of the present invention includes the above detection device and a display panel disposed opposite to the sensor unit with an air gap therebetween, and in a plan view, the detection region and the display region of the display panel overlap in the third direction.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

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Figure 4A

Figure 4B

Figure 5A

Figure 5B

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Figure 7A

Figure 7B

Figure 8

Figure 9

Figure 10

Figure 11

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DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiments for carrying out the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited by the content described in the following embodiments. Further, the constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be combined as appropriate. Also, the disclosure is merely an example, and those that can be easily conceived by those skilled in the art with appropriate modifications while maintaining the gist of the invention are naturally included in the scope of the present invention. In addition, for the purpose of making the description clearer, the drawings may schematically represent the width, thickness, shape, etc. of each part compared to the actual aspect, but this is merely an example and does not limit the interpretation of the present invention. Also, in this specification and each drawing, the same reference numerals may be assigned to the same elements as those described above with respect to the previously shown drawings, and detailed descriptions may be omitted as appropriate.

[0010] (Embodiment 1) FIG. 1 is a plan view showing a schematic configuration of a detection device applied to the detection system according to Embodiment 1. As shown in FIG. 1, the detection device 1 includes a sensor unit 10 and a control unit 20.

[0011] The sensor unit 10 includes a sensor substrate 11, a plurality of electrodes 12 provided in a detection region AA of the sensor substrate 11, and wirings 13 extending from each of the plurality of electrodes 12. The control unit 20 includes a control substrate 21, a detection circuit 22, a processing circuit 23, a power supply circuit 24, and an interface circuit 25.

[0012] The detection region AA of the sensor substrate 11 is a region in which a plurality of electrodes 12 arranged in a matrix in the Dx direction (first direction) and the Dy direction (second direction) are provided. The sensor substrate 11 is, for example, a glass substrate or a flexible printed circuit (FPC) having translucency.

[0013] In the present disclosure, the Dx direction (first direction) and the Dy direction (second direction) are orthogonal in the detection region AA of the sensor substrate 11. Further, in the present disclosure, the direction orthogonal to the Dx direction (first direction) and the Dy direction (second direction) is defined as the Dz direction (third direction).

[0014] In the example shown in FIG. 1, an example is shown in which five electrodes 12 are arranged in the Dx direction and four electrodes 12 are arranged in the Dy direction, and 5×4 (=20) electrodes 12 are provided. However, the number of electrodes 12 provided in the detection region AA of the sensor substrate 11 is not limited to this.

[0015] The control substrate 21 is electrically connected to the sensor substrate 11 via the wiring substrate 31. The wiring substrate 31 is, for example, a flexible printed circuit board. Each electrode 12 of the sensor unit 10 is connected to the detection circuit 22 of the control unit 20 via the wiring substrate 31.

[0016] The control substrate 21 is provided with a detection circuit 22, a processing circuit 23, a power supply circuit 24, and an interface circuit 25. The control substrate 21 is, for example, a rigid substrate.

[0017] The detection circuit 22 generates a detection value of each electrode 12 based on the detection signal of each electrode 12 output from the sensor substrate 11. The detection circuit 22 is, for example, an analog front end (AFE) IC.

[0018] The processing circuit 23 generates spatial coordinates indicating the position where the object to be detected (for example, the finger of an operator, etc.) exists on the detection region AA based on the detection values of each electrode 12 output from the detection circuit 22. The processing circuit 23 may be, for example, a programmable logic device (PLD) such as a field programmable gate array (FPGA), or may be, for example, a micro control unit (MCU).

[0019] The power supply circuit 24 is a circuit that supplies power to the detection circuit 22 and the processing circuit 23.

[0020] The interface circuit 25 is, for example, a USB controller IC, and is a circuit that controls communication between the processing circuit 23 and a host controller (not shown) of a host device on which the detection system is mounted.

[0021] FIG. 2 is a schematic cross-sectional configuration diagram of the detection system according to Embodiment 1.

[0022] The detection system 100 according to Embodiment 1 includes a detection device 1 and a display panel 200. The display panel 200 is disposed to face the sensor unit 10 of the detection device 1 with an air gap AG therebetween. The sensor unit 10 of the detection device 1 is disposed such that the detection region AA of the sensor unit 10 and the display region DA of the display panel 200 overlap in the Dz direction (third direction) in a plan view. The display panel 200 is exemplified by, for example, a liquid crystal display (LCD: Liquid Crystal Display). The display panel 200 may be, for example, an organic EL display (OLED: Organic Light Emitting Diode) or an inorganic EL display (micro LED, mini LED).

[0023] The sensor unit 10 includes a sensor substrate 11, electrodes 12, a shield 14, and a cover glass 15. The sensor unit 10 is laminated in the order of the shield 14, the sensor substrate 11, the electrodes 12, and the cover glass 15 from the display panel 200 side. Hereinafter, the surface of the cover glass 15 provided on the outermost layer is also referred to as the "detection surface".

[0024] The shield 14 is provided on the first surface of the sensor substrate 11 on the display panel 200 side. The electrodes 12 are provided on the second surface on the back side of the first surface of the sensor substrate 11. The cover glass 15 is provided on the second surface of the sensor substrate 11 via an adhesive layer OC. It is desirable that the adhesive layer OC be an adhesive having translucency. The adhesive layer OC may be formed of a translucent film having double-sided adhesiveness, such as OCA (Optical Clear Adhesive), for example.

[0025] FIG. 3 is a block diagram showing a configuration example of a detection unit of the detection device according to Embodiment 1.

[0026] As shown in FIG. 3, the detection unit 40 includes a signal detection unit 42, an A / D conversion unit 43, a signal processing unit 44, a coordinate extraction unit 45, a storage unit 46, and a data conversion unit 47. The signal detection unit 42 and the A / D conversion unit 43 are included in the detection circuit 22. The signal processing unit 44, the coordinate extraction unit 45, the storage unit 46, and the data conversion unit 47 are included in the processing circuit 23.

[0027] The signal detection unit 22 generates an output value Rawdata(n) of each electrode 12 based on a detection signal Det(n) of each electrode 12 output from the sensor substrate 11 (n is a natural number from 1 to N, and N is the number of electrodes in the detection region AA). The A / D conversion unit 43 samples the output value of each electrode 12 and converts it into a digital signal.

[0028] The data conversion unit 47 performs a linear conversion process on the output value Rawdata(n) of each electrode 12 and outputs it as a detection value S(n) of each electrode 12.

[0029] The signal processing unit 44 performs a predetermined signal process on the detection value S(n) of each electrode 12. Specifically, the signal processing unit 44 performs a comparison operation process on the detection value S(n) of each electrode 12.

[0030] The coordinate extraction unit 45 extracts the spatial coordinates of the position where the object to be detected exists based on the comparison operation result of the signal processing unit 44.

[0031] The storage unit 46 stores a first threshold value Sth1 and a second threshold value Sth2 used in the comparison operation process of the signal processing unit 44. Further, the storage unit 46 has a function of storing the spatial coordinates extracted by the coordinate extraction unit 45.

[0032] FIG. 4A is a schematic diagram showing the positional relationship between the position of the object to be detected in the space on the detection region and each electrode. FIG. 4B is a schematic diagram showing the spatial coordinates of the object to be detected in the space on the detection region. FIGS. 4A and 4B show an example in which the object to be detected F exists in the space on the detection region AA.

[0033] As shown in FIG. 4A, for each electrode 12 of the detection region AA, a capacitance corresponding to the distance D(n) between the object to be detected F existing in the space on the detection region AA and each electrode 12 is generated, and an output value Rawdata(n) corresponding to the capacitance is acquired by the detection circuit 22.

[0034] The processing circuit 23 extracts spatial coordinates R(Rx, Ry, Rz) indicating the position of the object to be detected F in the space on the detection region AA shown in FIG. 4B by using the output value Rawdata(n) of each electrode 12 generated by the detection circuit 22.

[0035] In the present disclosure, the spatial coordinates R(Rx, Ry, Rz) include first data Rx indicating the position in the Dx direction (first direction) on the detection region AA, second data Ry indicating the position in the Dy direction (second direction) on the detection region AA, and third data Rz indicating the position in the Dz direction (third direction) orthogonal to the Dx direction (first direction) and the Dy direction (second direction).

[0036] Also, in the present disclosure, the spatial coordinates R(Rx, Ry, Rz) indicate the position of the object to be detected F existing in the space on the detection surface with the surface of the cover glass 15 as the detection surface.

[0037] As described above, the detection device 1 according to the present disclosure is configured to detect the capacitance generated in each electrode 12 and detect the spatial coordinates of the position where the object to be detected F exists on the detection region AA. Therefore, compared with a configuration for detecting the planar coordinates of the contact position of the object to be detected F with the detection surface in order to detect the object to be detected F existing at a position away from the detection region AA in the Dz direction, it is necessary to increase the size of each electrode 12 to enhance the sensitivity. In the present disclosure, the size of each electrode 12 is, for example, 20×20 [mm 2 or more and about 40×40 [mm 2 is assumed.

[0038] FIG. 5A is a diagram showing a first example of the relationship between the distance between the detected object and the electrode and the output value. FIG. 5B is a diagram showing a second example of the relationship between the distance between the detected object and the electrode and the output value. In FIG. 5A, the horizontal axis represents the distance D between the detected object F and the electrode 12, and the vertical axis represents the output value Rawdata. In FIG. 5A, BL in the vertical axis direction represents the output value when the distance D between the detected object F and the electrode 12 is infinite. The vertical axis of FIG. 5B represents the difference value Rawdata - BL between the output value Rawdata and BL.

[0039] As shown in FIG. 5A, as the distance D between the detected object F and the electrode 12 increases, the decreasing rate of the output value Rawdata decreases. In other words, when the distance D between the detected object F and the electrode 12 becomes larger, the change rate of the output value Rawdata becomes smaller. Therefore, in the region where the output value Rawdata is below a certain level, the detection accuracy of the distance D between the detected object F and the electrode 12 decreases. Specifically, in the region below the lower limit value Lower_lim shown in FIG. 5A, the detection accuracy of the distance D between the detected object F and the electrode 12 cannot be maintained.

[0040] Also, as shown in FIG. 5A, as the distance D between the detected object F and the electrode 12 decreases, the increasing rate of the output value Rawdata rises exponentially. In other words, when the distance D between the detected object F and the electrode 12 becomes smaller, the change rate of the output value Rawdata increases rapidly. Therefore, in the region where the output value Rawdata is above a certain level, the detection accuracy of the distance D between the detected object F and the electrode 12 decreases. In particular, in the detection device 1 according to the present disclosure, since the size of each electrode 12 is large, when the detected object F exists at a position close to or in contact with the detection surface, the change amount of the output value Rawdata with respect to the change amount of the distance D between the detected object F and the electrode 12 becomes large. Specifically, in the region larger than the upper limit value Upper_lim shown in FIG. 5A, the detection accuracy of the distance D between the detected object F and the electrode 12 cannot be maintained.

[0041] Therefore, in the present disclosure, in the region where the lower limit value Lower_lim shown in FIG. 5A or more and the upper limit value Upper_lim or less, the output value Rawdata is linearly transformed. Specifically, the data conversion unit 47 of the processing circuit 23 obtains the difference value Rawdata - BL between the output value Rawdata shown in FIG. 5A and BL (see FIG. 5B), and executes a linear transformation process on this difference value Rawdata - BL.

[0042] FIG. 6 is a diagram showing the relationship between the distance between the detected object and the electrode and the detected value after the linear transformation process in Embodiment 1. In FIG. 6, the horizontal axis represents the distance D between the detected object F and the electrode 12, and the vertical axis represents the detected value S after the linear transformation process. The output value BL when the distance D between the detected object F and the electrode 12 is infinite is stored in the storage unit 46, for example.

[0043] The processing circuit 23 acquires the spatial coordinates indicating the position of the detected object F in the region where the first threshold value Sth1 shown in FIG. 6 or more and the second threshold value Sth2 or less (Sth1 ≦ S < Sth2). Thereby, the extraction accuracy of the spatial coordinates indicating the position of the detected object F in the space on the detection region AA can be maintained high.

[0044] FIG. 7A is a first diagram showing an example of a method for extracting the spatial coordinates of the detected object. In FIG. 7A, the horizontal axis represents the position in the Dx direction in the detection region AA (corresponding to the first data Rx of the spatial coordinates R (Rx, Ry, Rz)), and the vertical axis represents the signal value corresponding to the detected value S(n) of each electrode 12. FIG. 7A shows an example in which the detected object F exists in a space satisfying Sth1 ≦ S < Sth2.

[0045] The calculated value shown by the solid line in FIG. 7A is obtained, for example, by performing an interpolation process using the detected value S(n) of each electrode 12. The calculation method of the calculated value shown in FIG. 7A is not limited to the interpolation process, and may be, for example, a mode in which an approximation process is performed for calculation.

[0046] The processing circuit 23 extracts the spatial coordinates R (Rx, Ry, Rz) for which the calculated value shown in FIG. 7A becomes the maximum value Speak. The third data Rz indicating the position in the Dz direction can be calculated, for example, as a value proportional to the maximum value Speak of the calculated value.

[0047] Note that the method for extracting the spatial coordinates R (Rx, Ry, Rz) of the detected object F is not limited to the above method. The present disclosure is not limited by the method for extracting the spatial coordinates R (Rx, Ry, Rz) of the detected object F.

[0048] FIG. 7B is a second diagram showing an example of a method for extracting the spatial coordinates of the detected object. In FIG. 7B, an example is shown in which the detected object F exists at a position (D < D2, see FIG. 6) close to or in contact with the detection surface, and the processing result in the detection unit 40 is equal to or greater than the processing upper limit value S_upper_lim. In this case, as shown in FIG. 7B, an error occurs in the calculated value indicated by the solid line and deviates from the ideal value indicated by the broken line in the vicinity of the position where the detected object F exists, and the coordinate detection accuracy of the detected object F may decrease. In the example shown in FIG. 7B, the first data Rx, which is the calculated value, is a value that deviates from Rx', which is obtained by the ideal value, with respect to Rx'. Also, the third data Rz corresponding to the maximum value Speak of the calculated value also becomes a value that deviates from the ideal value.

[0049] Hereinafter, a specific example of the spatial coordinate detection operation in the detection device 1 according to Embodiment 1 will be described.

[0050] FIG. 8 is a conceptual diagram showing an operation example of the detection device according to Embodiment 1. FIG. 9 is a diagram showing the correspondence relationship of the spatial coordinates extracted in the detection device according to Embodiment 1. FIG. 10 is a flowchart showing an example of the spatial coordinate detection process in the detection device according to Embodiment 1.

[0051] In the operation example shown in FIG. 8, the horizontal axis represents time, and the vertical axis represents the minimum distance Dmin among the distances D(n) between the detected object F and each electrode 12. Also, Smax represents the maximum detection value among the detection values S(n) of each electrode 12 within the detection region AA.

[0052] Based on the detection signal Det(n) output from each electrode 12, the detection circuit 22 acquires the output value Rawdata(n) at each electrode 12 (step S100).

[0053] The data conversion unit 47 of the processing circuit 23 performs a linear conversion process on the output value Rawdata(n) of each electrode 12 to calculate the detection value S(n) of each electrode 12 (step S101). The signal processing unit 44 determines whether the maximum detection value Smax among the detection values S(n) of each electrode 12 output from the data conversion unit 47 is greater than or equal to the first threshold value Sth1 (Smax≥Sth1) (step S102).

[0054] When the maximum detection value Smax is less than the first threshold value Sth1 (Smax < Sth1) (step S102; No), the process returns to the process of step S100. That is, during the period until the time t1 in FIG. 8 when the maximum detection value Smax is less than the first threshold value Sth1 (Smax < Sth1), and the period after the time t6, it is assumed that the detected object F does not exist in the space where coordinates can be detected, and the coordinate extraction of the detected object F is not performed.

[0055] When the maximum detection value Smax is greater than or equal to the first threshold value Sth1 (Smax≥Sth1) (step S102; Yes), subsequently, the signal processing unit 44 of the processing circuit 23 determines whether the maximum detection value Smax is greater than or equal to the second threshold value Sth2 (Smax≥Sth2) (step S103).

[0056] When the maximum detection value Smax is less than the second threshold value Sth2 (Smax < Sth2) (step S103; No), that is, in the periods from time t1 to time t3 and from time t4 to time t6 in FIG. 8 where the maximum detection value Smax is equal to or greater than the first threshold value Sth1 and less than the second threshold value Sth2 (Sth1 ≤ Smax < Sth2), the coordinate extraction unit 45 of the processing circuit 23 uses the detection value S(n) of each electrode 12 to obtain the first data Rx, the second data Ry, and the third data Rz indicating the position of the detection object F in the space on the detection region AA, stores them in the storage unit 46 (step S104), and generates a space coordinate R(Rx, Ry, Rz) including the first data Rx, the second data Ry, and the third data Rz (step S107).

[0057] When the maximum detection value Smax is equal to or greater than the second threshold value Sth2 (Smax ≥ Sth2) (step S103; Yes), that is, in the period from time t3 to time t4 in FIG. 8, the coordinate extraction unit 45 of the processing circuit 23 sets the third data Rz indicating the position of the detection object F in the third direction stored in the storage unit 46 to "0" (step S105), further reads out the first data Rx and the second data Ry stored in the storage unit 46 (step S106), and generates a space coordinate R(Rx, Ry, 0) (step S107).

[0058] According to the above-described space coordinate detection process, when the maximum detection value Smax is equal to or greater than the first threshold value Sth1 and less than the second threshold value Sth2 (Sth1 ≤ Smax < Sth2), a space coordinate R(Rx, Ry, Rz) including the first data Rx, the second data Ry, and the third data Rz obtained using the detection value S(n) of each electrode 12 is generated.

[0059] Also, when the maximum detection value Smax is equal to or greater than the second threshold value Sth2 (Smax ≥ Sth2), a space coordinate R(Rx, Ry, 0) is generated by applying the first data Rx and the second data Ry stored in the storage unit 46 and setting the third data Rz to "0".

[0060] This can suppress a decrease in the acquisition accuracy of the proximity detection coordinates when the detected object F approaches or contacts the detection surface.

[0061] In the above-described spatial coordinate detection process, an example was given in which the maximum detection value Smax among the detection values S(n) of each electrode 12 in the detection region AA is used for threshold determination, but the present invention is not limited to this.

[0062] For example, when at least one of the detection values S(n) of each electrode 12 in the detection region AA is equal to or greater than a first threshold value Sth1 and less than a second threshold value Sth2, a spatial coordinate R(Rx, Ry, Rz) including a first data Rx, a second data Ry, and a third data Rz obtained using the detection values S(n) of each electrode 12 may be generated.

[0063] Further, for example, when at least one of the detection values S(n) of each electrode 12 in the detection region AA is equal to or greater than the second threshold value Sth2, a spatial coordinate R(Rx, Ry, 0) may be generated by applying the first data Rx and the second data Ry stored in the storage unit 46 and setting the third data Rz to "0".

[0064] (Embodiment 2) FIG. 11 is a diagram showing the relationship between the distance between the detected object and the electrode and the detection value after the linear conversion process in Embodiment 2. Since the configuration of the detection unit 40 in the detection device 1 is the same as that in Embodiment 1, detailed description thereof is omitted here. The third threshold value Sth3 in the present embodiment corresponds to the second threshold value Sth2 in Embodiment 1.

[0065] For example, when the size of each electrode 12 is large (for example, 40×40 [mm 2 )), there is a possibility that the detection accuracy in the Dx direction and the Dy direction may decrease.

[0066] As shown in FIG. 11, in the second embodiment, a second threshold value Sth2 and a third threshold value Sth3 greater than the second threshold value Sth2 are provided. When the maximum detection value Smax of each electrode 12 is equal to or greater than the second threshold value Sth2 and less than the third threshold value Sth3, third data Rz indicating the position of the detection object F in the third direction in the space on the detection region AA is acquired. Furthermore, the first data Rx and the second data Ry stored in the storage unit 46 are applied to generate spatial coordinates R (Rx, Ry, Rz).

[0067] FIG. 12 is a conceptual diagram showing an operation example of the detection device according to the second embodiment. FIG. 13 is a diagram showing the correspondence relationship of the spatial coordinates extracted in the detection device according to the second embodiment. FIG. 14 is a flowchart showing an example of the spatial coordinate detection process in the detection device according to the second embodiment.

[0068] Based on the detection signal Det(n) output from each electrode 12, the detection circuit 22 acquires the output value Rawdata(n) at each electrode 12 (step S200).

[0069] The data conversion unit 47 of the processing circuit 23 performs a linear conversion process on the output value Rawdata(n) of each electrode 12 to calculate the detection value S(n) of each electrode 12 (step S201). The signal processing unit 44 determines whether the maximum detection value Smax among the detection values S(n) of each electrode 12 output from the detection circuit 22 is equal to or greater than the first threshold value Sth1 (Smax≧Sth1) (step S202).

[0070] When the maximum detection value Smax is less than the first threshold value Sth1 (Smax < Sth1) (step S202; No), the process returns to the process of step S200. That is, during the period until time t1 in FIG. 12 when the maximum detection value Smax is less than the first threshold value Sth1 (Smax < Sth1), and after time t6, it is assumed that the detection object F does not exist in the spatially detectable space, and the coordinate extraction of the detection object F is not performed.

[0071] When the maximum detection value Smax is greater than or equal to the first threshold value Sth1 (Smax ≥ Sth1) (step S202; Yes), subsequently, the signal processing unit 44 of the processing circuit 23 determines whether the maximum detection value Smax is greater than or equal to the second threshold value Sth2 (Smax ≥ Sth2) (step S203).

[0072] When the maximum detection value Smax is less than the second threshold value Sth2 (Smax < Sth2) (step S203; No), that is, during the period from time t1 to time t2 and from time t5 to time t6 in FIG. 12 where the maximum detection value Smax is greater than or equal to the first threshold value Sth1 and less than the second threshold value Sth2 (Sth1 ≤ Smax < Sth2), the coordinate extraction unit 45 of the processing circuit 23 uses the detection value S(n) of each electrode 12 to obtain the first data Rx, the second data Ry, and the third data Rz indicating the position of the detected object F in the space on the detection region AA, stores them in the storage unit 46 (step S204), and generates a space coordinate R (Rx, Ry, Rz) including the first data Rx, the second data Ry, and the third data Rz (step S209).

[0073] When the maximum detection value Smax is greater than or equal to the second threshold value Sth2 (Smax ≥ Sth2) (step S203; Yes), subsequently, the signal processing unit 44 of the processing circuit 23 determines whether the maximum detection value Smax is greater than or equal to the third threshold value Sth3 (Smax ≥ Sth3) (step S205).

[0074] When the maximum detected value Smax is less than the third threshold value Sth3 (Smax < Sth3) (step S205; No), that is, during the period from time t2 to time t3 and the period from time t4 to time t6 in FIG. 12 where the maximum detected value Smax is greater than or equal to the second threshold value Sth2 and less than the third threshold value Sth3 (Sth2 ≤ Smax < Sth3), the coordinate extraction unit 45 of the processing circuit 23 uses the detected value S(n) of each electrode 12 to obtain third data Rz indicating the position of the detected object F in the third direction in the space on the detection region AA (step S206). Further, the first data Rx and the second data Ry stored in the storage unit 46 are read out (step S208), and spatial coordinates R(Rx, Ry, Rz) are generated (step S209).

[0075] When the maximum detected value Smax is greater than or equal to the third threshold value Sth3 (Smax ≥ Sth3) (step S205; Yes), that is, during the period from time t3 to time t4 in FIG. 12, the coordinate extraction unit 45 of the processing circuit 23 sets the third data Rz indicating the position of the detected object F in the third direction stored in the storage unit 46 to "0" (step S207). Further, the first data Rx and the second data Ry stored in the storage unit 46 are read out (step S208), and spatial coordinates R(Rx, Ry, 0) are generated (step S209).

[0076] By the above-described spatial coordinate detection process, when the maximum detected value Smax is greater than or equal to the first threshold value Sth1 and less than the second threshold value Sth2 (Sth1 ≤ Smax < Sth2), spatial coordinates R(Rx, Ry, Rz) including the first data Rx, the second data Ry, and the third data Rz obtained using the detected value S(n) of each electrode 12 are generated.

[0077] Also, when the maximum detected value Smax is greater than or equal to the second threshold value Sth2 and less than the third threshold value Sth3 (Sth2 ≤ Smax < Sth3), third data Rz indicating the position of the detected object F in the third direction in the space on the detection region AA is obtained using the detected value S(n) of each electrode 12, and spatial coordinates R(Rx, Ry, Rz) to which the first data Rx and the second data Ry stored in the storage unit 46 are applied are generated.

[0078] Also, when the maximum detection value Smax is greater than or equal to the third threshold value Sth3 (Smax ≧ Sth3), the first data Rx and the second data Ry stored in the storage unit 46 are applied, and a spatial coordinate R (Rx, Ry, 0) with the third data Rz being "0" is generated.

[0079] This can suppress a decrease in the acquisition accuracy of the proximity detection coordinates when the size of each electrode 12 is large and the detection accuracy in the Dx direction and the Dy direction decreases as the detected object F approaches the detection surface.

[0080] In the above-described spatial coordinate detection process, an example has been illustrated in which the maximum detection value Smax among the detection values S(n) of each electrode 12 within the detection region AA is used for threshold determination, but it is not limited thereto.

[0081] For example, when at least one of the detection values S(n) of each electrode 12 within the detection region AA is greater than or equal to the first threshold value Sth1 and less than the second threshold value Sth2, a spatial coordinate R (Rx, Ry, Rz) including the first data Rx, the second data Ry, and the third data Rz obtained using the detection values S(n) of each electrode 12 may be generated.

[0082] Also, for example, when at least one of the detection values S(n) of each electrode 12 within the detection region AA is greater than or equal to the second threshold value Sth2 and less than the third threshold value Sth3, the third data Rz indicating the position of the detected object F in the third direction in the space on the detection region AA is obtained using the detection values S(n) of each electrode 12, and further, a spatial coordinate R (Rx, Ry, Rz) to which the first data Rx and the second data Ry stored in the storage unit 46 are applied may be generated.

[0083] Also, for example, when at least one of the detection values S(n) of each electrode 12 within the detection region AA is greater than or equal to the third threshold value Sth3, a spatial coordinate R (Rx, Ry, 0) may be generated by applying the first data Rx and the second data Ry stored in the storage unit 46 and setting the third data Rz to "0".

[0084] As described above, the preferred embodiments of the present disclosure have been explained. However, the present disclosure is not limited to such embodiments. The content disclosed in the embodiments is merely an example, and various modifications are possible without departing from the spirit of the present disclosure. Appropriate modifications made without departing from the spirit of the present disclosure also naturally belong to the technical scope of the present disclosure.

Explanation of Reference Numerals

[0085] 1 Detection device 10 Sensor section 11 Sensor substrate 12 Electrode 13 Wiring 14 Shield 15 Cover glass 20 Control section 21 Control substrate 22 Detection circuit 23 Processing circuit 24 Power supply circuit 25 Interface circuit 31 Wiring substrate 40 Detection unit 42 Signal detection unit 43 A / D conversion unit 44 Signal processing unit 45 Coordinate extraction unit 46 Storage unit 200 Display panel AA Detection area AG Air gap D, D(n) Distance DA Display area Det(n) Detection signal F Object to be detected OC Adhesive layer Rawdata, Rawdata(n) Output value Rx First data Ry Second data Rz Third data S, S(n) Detection value S_lower_lim Processing lower limit value S_upper_lim Processing upper limit value Sth1 First threshold value Sth2 second threshold value Sth3 third threshold value

Claims

1. a sensor unit provided with a detection area; a plurality of electrodes arranged in the detection area in a first direction and a second direction different from the first direction; a detection circuit that generates a detection value corresponding to the capacitance generated for each electrode based on the detection signals output from the plurality of electrodes; a processing circuit that generates spatial coordinates indicating the position of the object to be detected on the detection area; comprising; the spatial coordinates include first data indicating the position in the first direction, second data indicating the position in the second direction, and third data indicating the position in a third direction orthogonal to the first direction and the second direction; a first threshold value for the detection value and a second threshold value larger than the first threshold value are set in the processing circuit; when at least one of the detection values for each electrode is equal to or greater than the first threshold value and less than the second threshold value, based on the detection values of the plurality of electrodes, first data, second data, and third data are acquired, and spatial coordinates including the first data, second data, and third data are generated; comprising a storage unit that stores first data, second data, and third data generated based on the detection values of the plurality of electrodes when at least one of the detection values for each electrode is equal to or greater than the first threshold value and less than the second threshold value; when at least one of the detection values for each electrode is equal to or greater than the second threshold value, the first data and the second data stored in the storage unit are read out, the third data is set to 0, and spatial coordinates including the first data, second data, and third data are generated; a detection device.

2. a third threshold value larger than the second threshold value is set in the processing circuit; when at least one of the detection values for each electrode is equal to or greater than the second threshold value and less than the third threshold value, third data is acquired based on the detection values of the plurality of electrodes, the first data and the second data stored in the storage unit are read out, and spatial coordinates including the first data, second data, and third data are generated; when at least one of the detection values for each electrode is equal to or greater than the third threshold value, the first data and the second data stored in the storage unit are read out, the third data is set to 0, and spatial coordinates including the first data, second data, and third data are generated; the detection device according to Claim 1.

3. the electrode is such that the length of the side extending in the first direction is 20 [mm] or more and 40 [mm] or less; The length of the side extending in the second direction is 20 [mm] or more and 40 [mm] or less, The detection device according to claim 1 or 2.

4. The sensor unit is, A sensor substrate provided with a plurality of the electrodes, A cover glass overlapping the sensor substrate in the third direction via an adhesive layer, Comprises, The spatial coordinates indicate the position of the object to be detected existing in the space on the detection surface, with the surface of the cover glass as the detection surface. The detection device according to any one of claims 1 to 3.

5. The detection device according to any one of claims 1 to 4, A display panel disposed opposite to the sensor unit with an air gap therebetween, Comprises, In a plan view, the detection region and the display region of the display panel overlap in the third direction. Detection system.

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