Detection device

Abstract

To provide a detection device capable of enhancing accuracy of a detection position of a detection object at an outer edge side of a detection area.SOLUTION: A detection device includes: a plurality of first detection electrode; at least one second detection electrode arranged along a side of a detection area; and a coordinate calculation circuit which calculates a detection position of a detection object. When another first detection electrode is arranged between a first detection electrode showing a maximum detection value and a side of a detection area nearest to the first detection electrode showing the maximum detection value, the coordinate calculation circuit calculates the detection position of the detection object on the basis of detection values of the first detection electrode showing the maximum detection value and a plurality of first detection electrodes adjacent to the first detection electrode showing the maximum detection value. When the first detection electrode showing the maximum detection value is arranged at an outer edges side of the detection area, the coordinate calculation circuit calculates the detection position of the detection object on the basis of detection values of the first detection electrode showing the maximum detection value, at least one second detection electrode adjacent to the first detection electrode showing the maximum detection value, and the plurality of first detection electrodes.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a detection device. [Background technology]

[0002] A touch panel, for example, is known as a sensor that detects contact or proximity of a detectable object such as a finger (see Patent Document 1). The display device described in Patent Document 1 has a plurality of detection electrodes provided in a detection area (described as a display area in Patent Document 1) and a peripheral area, and can perform touch detection in the peripheral area in addition to touch detection in the detection area. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-169680 Summary of the Invention [Problem to be solved by the invention]

[0004] In Patent Document 1, the detection electrodes in the peripheral region have different areas and shapes from the detection electrodes in the detection region, which may reduce the accuracy of detecting the position of the object to be detected on the outer edge side of the detection region.

[0005] An object of the present invention is to provide a detection device that can improve the accuracy of detecting the position of a detection target on the outer edge side of a detection area. [Means for solving the problem]

[0006] A detection device according to one embodiment of the present invention comprises a plurality of first detection electrodes arranged in a matrix in a detection area of ​​a substrate; at least one second detection electrode arranged in a peripheral area outside the detection area, adjacent to the plurality of first detection electrodes, and arranged along an edge of the detection area; and a coordinate calculation circuit that calculates the detection position of a detectable object, wherein when another first detection electrode is arranged between the first detection electrode showing the maximum detection value and the edge of the detection area closest to the first detection electrode showing the maximum detection value, the coordinate calculation circuit calculates the detection position of the detectable object based on the first detection electrode showing the maximum detection value and the detection values ​​of the plurality of first detection electrodes adjacent to the first detection electrode showing the maximum detection value, and when the first detection electrode showing the maximum detection value is arranged on the outer edge of the detection area, the coordinate calculation circuit calculates the detection position of the detectable object based on the detection values ​​of the first detection electrode showing the maximum detection value and at least one second detection electrode and the plurality of first detection electrodes adjacent to the first detection electrode showing the maximum detection value.

[0007] A detection device according to one embodiment of the present invention comprises a plurality of first detection electrodes arranged in a matrix in a detection area of ​​a substrate, and at least one second detection electrode arranged in a peripheral area outside the detection area, adjacent to the plurality of first detection electrodes, and arranged along an edge of the detection area; when the first detection electrode showing the maximum detection value is arranged on the outer edge side of the detection area, the detection position of the object to be detected is calculated based on the detection values ​​of the first detection electrode showing the maximum detection value, at least one second detection electrode adjacent to the first detection electrode showing the maximum detection value, and the plurality of first detection electrodes. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view schematically showing a detection device according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing a display device with a detection device having the detection device according to the embodiment. [Figure 3] FIG. 3 is a block diagram illustrating an example of the configuration of the detection device according to the embodiment. [Figure 4] FIG. 4 is an explanatory diagram for explaining a method for calculating the first correction value of the second detection electrode, in which the object to be detected is located on the outer edge side of the detection area and in the center of the first detection electrode. [Figure 5] FIG. 5 is an explanatory diagram for schematically explaining the relationship between the detection value in FIG. 4 and the first and second detection electrodes. [Figure 6] FIG. 6 is an explanatory diagram for explaining a method for calculating the first correction value of the second detection electrode, and is an explanatory diagram for the case where the object to be detected is located between the first detection electrode and the second detection electrode on the outer edge side of the detection area. [Figure 7] FIG. 7 is an explanatory diagram for schematically explaining the relationship between the detection value in FIG. 6 and the first and second detection electrodes. [Figure 8] FIG. 8 is a graph schematically showing the relationship between the first correction value of the second detection electrode and the height of the object to be detected. [Figure 9] FIG. 9 is an explanatory diagram for explaining a method of calculating the second correction value of the second detection electrode. [Figure 10] FIG. 10 is a graph schematically showing the relationship between the detection value of the second detection electrode in FIG. 9 and the position of the object to be detected. [Figure 11] FIG. 11 is a graph schematically showing the relationship between the second correction value of the second detection electrode and the height of the object to be detected. [Figure 12] FIG. 12 is a table showing an example of a correction table for the detection values ​​of the second detection electrodes. [Figure 13] FIG. 13 is a table showing an example of a correction table for the detection values ​​of the second detection electrodes. [Figure 14] FIG. 14 is a flowchart illustrating a detection method of the detection device according to the embodiment. [Figure 15] FIG. 15 is an explanatory diagram illustrating a method for detecting a detectable substance using the second detection electrode, and illustrates a case where the detectable substance is in the detection area. [Figure 16] FIG. 16 is an explanatory diagram illustrating a method for detecting a detection target using the second detection electrode, and illustrates a case where the detection target is in the peripheral region. [Figure 17] FIG. 17 is a plan view schematically showing a detection device according to a first modified example. [Figure 18] FIG. 18 is a plan view schematically showing a detection device according to a second modified example. [Figure 19] FIG. 19 is a plan view schematically showing a detection device according to a third modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate. Note that the disclosure is merely an example, and any appropriate modifications that a person skilled in the art can easily make while maintaining the gist of the present disclosure are naturally included within the scope of the present disclosure. Furthermore, for clarity of explanation, the drawings may schematically depict the width, thickness, shape, etc. of each part compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this disclosure and each figure, elements similar to those previously described with reference to the preceding figures may be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0010] In this specification and claims, when expressing an aspect of placing another structure on top of a certain structure, the term "on top" is used, unless otherwise specified, to include both a case in which another structure is placed directly on top of a certain structure so as to be in contact with the certain structure, and a case in which another structure is placed above a certain structure via yet another structure.

[0011] (Embodiment) FIG. 1 is a plan view schematically illustrating a detection device according to an embodiment. As shown in FIG. 1, the detection device 3 includes a substrate 31, a plurality of first detection electrodes 33, a plurality of second detection electrodes 34-1, 34-2, 34-3, and 34-4, a wiring substrate 115, and a detection IC (Integrated Circuit) 45. The detection device 3 is a self-capacitance touch detection device. The detection device 3 can detect a detection target Fg in contact with the detection surface (hereinafter referred to as touch detection) and detect the position or movement of the detection target Fg when not in contact with the detection surface (hereinafter referred to as hover detection). In the following description, when there is no need to distinguish between touch detection and hover detection, the terms may simply be referred to as touch detection.

[0012] The detection device 3 has a detection area AA and a peripheral area BE outside the detection area AA. The detection area AA is an area in which a plurality of first detection electrodes 33 are provided, and is an area for detecting a detectable object Fg, such as a finger, in contact with or approaching the detection area AA. The detection area AA is rectangular with four sides AAs1, AAs2, AAs3, and AAs4. The peripheral area BE is an area in which the plurality of first detection electrodes 33 are not provided, and is an area between the four sides AAs1, AAs2, AAs3, and AAs4 of the detection area AA and the outer periphery of the substrate 31.

[0013] In the following description, the first direction Dx is a direction in a plane parallel to the substrate 31. The second direction Dy is a direction in a plane parallel to the substrate 31, and is a direction perpendicular to the first direction Dx. The second direction Dy may intersect the first direction Dx without being perpendicular thereto. The third direction Dz is a direction perpendicular to the first direction Dx and the second direction Dy, and is the normal direction to the main surface of the substrate 31. Furthermore, "planar view" refers to the positional relationship when viewed from a direction perpendicular to the substrate 31.

[0014] The multiple first detection electrodes 33 are arranged in a matrix in the detection area AA of the substrate 31. In other words, the multiple first detection electrodes 33 are arranged side by side in the first direction Dx and the second direction Dy. The multiple first detection electrodes 33 are each electrically connected to the detection IC 45 via wiring (not shown).

[0015] The plurality of second detection electrodes 34-1, 34-2, 34-3, and 34-4 are provided in the peripheral region BE of the substrate 31. In the following description, when there is no need to distinguish between the plurality of second detection electrodes 34-1, 34-2, 34-3, and 34-4, they may be simply referred to as second detection electrodes 34.

[0016] The multiple second detection electrodes 34-1, 34-2, 34-3, and 34-4 are arranged surrounding the multiple first detection electrodes 33 provided in the detection area AA. More specifically, the second detection electrode 34-1 extends in the second direction Dy along a side AAs1 of the detection area AA. The second detection electrode 34-2 extends in the second direction Dy along a side AAs2 of the detection area AA. The detection area AA and the multiple first detection electrodes 33 are provided between the adjacent second detection electrodes 34-1 and 34-2 in the first direction Dx.

[0017] The second detection electrode 34-3 extends in the first direction Dx along a side AAAs3 of the detection area AA. The second detection electrode 34-4 extends in the first direction Dx along a side AAAs4 of the detection area AA. The detection area AA and the plurality of first detection electrodes 33 are provided between the adjacent second detection electrodes 34-3 and 34-4 in the second direction Dy. The plurality of second detection electrodes 34 are each electrically connected to the detection IC 45 via wiring (not shown).

[0018] Each of the second detection electrodes 34-1, 34-2, 34-3, and 34-4 is disposed adjacent to a plurality of first detection electrodes 33 arranged along each side AAs1, AAs2, AAs3, and AAs4 of the detection area AA. The second detection electrodes 34 have different areas and shapes from the first detection electrodes 33. In the direction in which each of the second detection electrodes 34 extends, the length of each of the second detection electrodes 34 is longer than the length of each of the first detection electrodes 33. In the direction intersecting the direction in which the second detection electrodes 34 extend, the width of each of the second detection electrodes 34 is smaller than the width of each of the first detection electrodes 33.

[0019] Specifically, the length of the second detection electrodes 34-1, 34-2 extending in the second direction Dy is greater than the length of the multiple first detection electrodes 33 in the second direction Dy. The width of the second detection electrodes 34-1, 34-2 in the first direction Dx, which intersects with the extension direction of the second detection electrodes 34-1, 34-2, is smaller than the width of the multiple first detection electrodes 33 in the first direction Dx. Furthermore, the length of the second detection electrodes 34-3, 34-4 extending in the first direction Dx is greater than the length of the multiple first detection electrodes 33 in the first direction Dx. The width of the second detection electrodes 34-3, 34-4 in the second direction Dy, which intersects with the extension direction of the second detection electrodes 34-1, 34-2, is smaller than the width of the multiple first detection electrodes 33 in the second direction Dy.

[0020] The time constants of the second detection electrodes 34 are substantially equal to those of the first detection electrodes 33. The time constants of the second detection electrodes 34 can be matched to those of the first detection electrodes 33 by, for example, changing the shape (size) and the intervals GA1 and GA2 between the second detection electrodes 34 and the first detection electrodes 33. Alternatively, the wiring resistance (time constant) can be adjusted by changing the length or thickness of the wiring (not shown) connected to the second detection electrodes 34. In the example shown in FIG. 1, the second detection electrodes 34-1 and the second detection electrodes 34-3 have different lengths in the extension direction, so the intervals GA1 and GA2 may be set different depending on the shape (size) of each electrode. Furthermore, the second detection electrodes 34 are provided one by one along each side AAs1, AAs2, AAs3, and AAs4 of the detection area AA. However, as described below, the second detection electrodes 34 may be provided separately along each side AAs1, AAs2, AAs3, and AAs4.

[0021] A wiring board 115 is electrically connected to the substrate 31. The wiring board 115 is, for example, a flexible printed circuit (FPC) or a rigid board. A detection IC 45 is provided on the wiring board 115. The detection IC 45 includes a control circuit that controls touch detection of the detection device 3. The detection IC 45 includes, for example, a drive circuit that outputs a drive signal and a detection circuit 40 (see FIG. 3) that processes the detection signals Vdet1 and Vdet2. The detection IC 45 supplies drive signals to the plurality of first detection electrodes 33 and the plurality of second detection electrodes 34. The plurality of first detection electrodes 33 and the plurality of second detection electrodes 34 output detection signals Vdet1 and Vdet2 to the detection IC 45 based on changes in their respective self-capacitances.

[0022] 1, the detection device 3 calculates the detection position TA where the first detection electrode 33 is in contact with or in proximity to the object to be detected Fg, based on the detection signals Vdet1 of the first detection electrode 33 at the position where the object to be detected Fg overlaps and the plurality of first detection electrodes 33 adjacent thereto. This makes it possible to improve the accuracy of the detection position TA within the area overlapping with one first detection electrode 33.

[0023] In FIG. 1, the detection position TA is calculated based on the detection signals Vdet1 from a total of five first detection electrodes 33: the first detection electrode 33 at the position where the detectable object Fg overlaps, two first detection electrodes 33 adjacent to each other in the first direction Dx, and two first detection electrodes 33 adjacent to each other in the second direction Dy. However, the detection position TA may be calculated using the detection signals Vdet1 from five or more first detection electrodes 33 in addition to the first detection electrode 33 at the position where the detectable object Fg overlaps. Furthermore, when the detectable object Fg is located on the outer edge of the detection area AA, the detection position TA is calculated using the detection signal Vdet2 from at least one second detection electrode 34. The method for calculating the position of the detectable object Fg will be described later with reference to FIG. 4 and subsequent figures.

[0024] 2 is a cross-sectional view showing a display device with a detector having a detector according to an embodiment. As shown in FIG. 2, the display device with a detector 1 has a display panel 2, a detector 3, and a cover member 111. The display panel 2, the detector 3, and the cover member 111 are stacked in this order.

[0025] The display panel 2 includes an array substrate SUB1, a counter substrate SUB2, a first polarizer PL1, and a second polarizer PL2. The first polarizer PL1, the array substrate SUB1, the counter substrate SUB2, and the second polarizer PL2 are stacked in this order.

[0026] The array substrate SUB1 is a drive circuit substrate for driving a plurality of pixels. The counter substrate SUB2 is provided opposite the array substrate SUB1. A liquid crystal layer, which is a display function layer, is provided between the array substrate SUB1 and the counter substrate SUB2.

[0027] A display IC (Integrated Circuit) 47 and a wiring board 114 are connected to the protruding portion of the array substrate SUB1. The display IC 47 includes a control circuit and the like that controls the display of the display panel 2. This example is not limiting, and the display IC 47 may be mounted on the wiring board 114. The arrangement of the display IC 47 is not limited to this, and it may be provided, for example, on a control board or a flexible board outside the module. The wiring board 114 is formed, for example, by a flexible wiring board.

[0028] The substrate 31 of the detection device 3 is bonded to the display panel 2 via an adhesive layer 113. However, the adhesive layer 113 may not be provided, and an air gap may be provided between the substrate 31 and the display panel 2. The plurality of first detection electrodes 33 and the plurality of second detection electrodes 34 are provided on the same substrate 31. The plurality of first detection electrodes 33 and the plurality of second detection electrodes 34 are not limited to being provided on the same layer, and may be provided on different layers. The plurality of first detection electrodes 33 are formed of a translucent conductive material such as ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide). The plurality of second detection electrodes 34 may be formed of the same material as the plurality of first detection electrodes 33, or may be formed of a different material from the plurality of first detection electrodes 33, such as a metal material.

[0029] A shielding layer 118 is provided on the surface of the substrate 31 opposite to the surface on which the plurality of first detection electrodes 33 and the plurality of second detection electrodes 34 are provided. In other words, the shielding layer 118 is provided between the substrate 31 of the detection device 3 and the display panel 2. In addition, the adhesive layer 113 is in contact with the shielding layer 118 provided on the substrate 31. The shielding layer 118 is electrically connected to the wiring substrate 115 via a shielding wiring substrate 119. The shielding wiring substrate 119 is, for example, a flexible printed circuit board.

[0030] The shield layer 118 contains, for example, a conductive, translucent oxide such as ITO or IZO, or a metal. Examples of the metal include metals (zero-valent metals) such as molybdenum, tungsten, tantalum, aluminum, and copper. The shield layer 118 may have a single-layer structure or a multilayer structure. When the shield layer 118 has a multilayer structure, the shield layer 118 may have a layer containing an oxide and a layer containing a metal. The shield layer 118 may be any layer as long as it is transparent and conductive, and can be called a transparent conductive layer.

[0031] A fixed potential (for example, ground potential) or a signal in phase with the signals applied to the plurality of first detection electrodes 33 is supplied to the shield layer 118 via the shield wiring substrate 119. In this embodiment, the shield layer 118 is provided between the detection device 3 and the display panel 2, and therefore the shield layer 118 can block noise from the display panel 2.

[0032] The cover member 111 is attached onto the detection device 3 via an adhesive layer 112. For example, a glass substrate or a resin substrate is used for the cover member 111. An upper surface 111a of the cover member 111 is a detection surface for touch detection (or hover detection), and the detection device 3 detects a detection object Fg that is in contact with or in proximity to the upper surface 111a.

[0033] The display panel 2 is, for example, a liquid crystal display panel (LCD: Liquid Crystal Display). However, without being limited thereto, the display panel 2 may be, for example, an organic light emitting diode (OLED) display panel or an inorganic light emitting diode (micro LED, mini LED) display panel. Alternatively, the display panel 2 may be an electrophoretic display panel (EPD: Electrophoretic Display) that uses electrophoretic elements as display elements. Furthermore, the display device 1 with a detection device is not limited to a configuration in which the detection device 3 is provided on the display panel 2, and may be a configuration in which the detection device 3 is integrally formed with the display panel 2. In other words, at least one of the substrate 31, the first detection electrode 33, and the second detection electrode 34 of the detection device 3 may be shared with a member constituting the display panel 2.

[0034] Fig. 3 is a block diagram showing an example of the configuration of a detection device according to an embodiment. As shown in Fig. 3, the detection device 3 includes a sensor unit 10, a detection circuit 40, and a host 50. The sensor unit 10 is composed of the above-mentioned multiple first detection electrodes 33 and multiple second detection electrodes 34. The sensor unit 10 outputs detection signals Vdet1 and Vdet2 detected by self-capacitance touch detection to the detection circuit 40.

[0035] The detection circuit 40 is, for example, an analog front end (AFE) circuit. The detection circuit 40 is a signal processing circuit including a detection signal amplifier circuit 42, an A / D conversion circuit 43, and a signal processing circuit 44.

[0036] The detection signal amplifier circuit 42 amplifies the detection signals Vdet1 and Vdet2. The A / D conversion circuit 43 converts the analog signal output from the detection signal amplifier circuit 42 into a digital signal. The signal processing circuit 44 is a circuit that processes the digital signal output from the A / D conversion circuit 43, and is, for example, a digital filter circuit. The detection circuit 40 processes the detection signals Vdet1 and Vdet2 from the sensor unit 10 and outputs detection values ​​S1 and S2 that are used for calculation in the host 50. The detection value S1 is a signal based on the detection signal Vdet1 from the first detection electrode 33. The detection value S2 is a signal based on the detection signal Vdet2 from the second detection electrode 34.

[0037] The host 50 includes a readout circuit 51, a first coordinate calculation circuit 52, a correction circuit 53, a second coordinate calculation circuit 54, a determination circuit 55, and a memory circuit 56. The readout circuit 51 receives the detection values ​​S1 and S2 from the detection circuit 40 in a predetermined order. The first coordinate calculation circuit 52 calculates the position of the object to be detected Fg based on the peak positions of the detection values ​​S1 and S2. For example, the first coordinate calculation circuit 52 calculates whether the object to be detected Fg is located within the detection area AA or in the peripheral area BE. Alternatively, the first coordinate calculation circuit 52 calculates whether the object to be detected Fg is located on the outer edge of the detection area AA or in the center of the detection area AA.

[0038] The correction circuit 53 is a circuit that corrects the detection value S2 of the second detection electrode 34. More specifically, when the position of the object to be detected Fg is on the outer edge side of the detection area AA, based on information about the position of the object to be detected Fg from the first coordinate calculation circuit 52, the correction circuit 53 receives the first correction value γs and the second correction value γp of the second detection electrode 34 to be corrected from the memory circuit 56, and corrects the detection value S2 of the second detection electrode 34.

[0039] The second coordinate calculation circuit 54 is a circuit that calculates the position of the object to be detected Fg based on the first detection electrode 33 of the detection value S1 at the peak position, the detection values ​​S1 of the plurality of first detection electrodes 33 adjacent thereto, and the detection value S2 corrected by the correction circuit 53. The correction of the detection value S2 by the correction circuit 53 and the calculation by the second coordinate calculation circuit 54 will be described in detail with reference to FIG. 7 and subsequent figures.

[0040] The determination circuit 55 is a circuit that compares the detection values ​​S1 and S2 with a preset reference value to determine whether or not the object to be detected Fg is in contact with or approaching the object to be detected Fg. When touch detection (or hover detection) of the object to be detected Fg is detected, the determination circuit 55 is a circuit that compares the multiple detection values ​​S1 and S2 to determine the peak positions of the detection values ​​S1 and S2.

[0041] The storage circuit 56 is a circuit that stores, as a correction table, information on a reference value for determining touch detection (or hover detection) and a correction value for the detection value S2.

[0042] 3, for ease of understanding, each process performed by the host 50 is shown as a separate circuit, but this is merely an example and can be changed as appropriate. For example, the first coordinate calculation circuit 52, the correction circuit 53, the second coordinate calculation circuit 54, and the determination circuit 55 may be realized as a single circuit.

[0043] Next, a method for calculating a correction value for the detection value S2 of the second detection electrode 34 in the detection device 3 of this embodiment will be described. FIG. 4 is an explanatory diagram for explaining a method for calculating a first correction value for the second detection electrode, and is an explanatory diagram for a case where the object to be detected is located on the outer edge side of the detection area and in the center of the first detection electrode. For ease of understanding, FIG. 4 shows an example in which the first detection electrodes 33 are arranged in three rows and five columns. The multiple first detection electrodes 33 are shown in the order of first detection electrodes 33-1, 33-2, 33-3, ..., 33-15, starting from the top left of FIG. 4 . However, when it is not necessary to distinguish between the first detection electrodes 33-1, 33-2, 33-3, ..., 33-15, they will simply be referred to as first detection electrodes 33.

[0044] The following explanation will mainly focus on the correction of the detection value S2-1 of the second detection electrode 34-1 when the detectable object Fg is located in an area along the side AAs1 on the outer edge of the detection area AA. However, the explanation for the correction of the detection value S2-1 of the second detection electrode 34-1 can also be applied to the correction of the detection values ​​S2-2, S2-3, and S2-4 of the other second detection electrodes 34-2, 34-3, and 34-4. Also, Fig. 4 shows both a case where the detectable object Fg (shown in black) is located on the outer edge of the detection area AA (at the center of the first detection electrode 33-2) and a case where the detectable object Fg (shown in dotted line) is located in the center of the detection area AA (at a position overlapping with the first detection electrode 33-8).

[0045] In this embodiment, the "center of the detection area AA" refers to a region that does not overlap with the plurality of first detection electrodes 33 adjacent to each side AAs1, AAs2, AAs3, and AAs4 of the detection area AA, and is a region that is inside these plurality of first detection electrodes 33. In the example shown in FIG. 4, the region that overlaps with the plurality of first detection electrodes 33-5, 33-8, and 33-11 corresponds to the "center of the detection area AA." The region that overlaps with the plurality of first detection electrodes 33-1, 33-2, 33-3, 33-4, 33-6, 33-7, 33-9, 33-10, 33-12, 33-13, 33-14, and 33-15 corresponds to the "outer edge side of the detection area AA."

[0046] In other words, when the detectable object Fg is located in the center of the detection area AA (first detection electrode 33-8), another first detection electrode 33-9 (or first detection electrode 33-7) is arranged between the first detection electrode 33-8 exhibiting the maximum detection value S1 and the side AAs4 (or side AAs3) of the detection area AA that is closest to the first detection electrode 33-8 exhibiting the maximum detection value S1. Alternatively, when the detectable object Fg is located on the outer edge side of the detection area AA (first detection electrode 33-2), no other first detection electrode 33 is arranged between the first detection electrode 33-2 exhibiting the maximum detection value S1 and the side AAs1 of the detection area AA that is closest to the first detection electrode 33-2 exhibiting the maximum detection value S1.

[0047] When the object to be detected Fg (indicated by a dotted line) is in the center of the detection area AA (for example, at a position overlapping with the first detection electrode 33-8), the second coordinate calculation circuit 54 calculates the detection position of the object to be detected Fg based on the detection value S1 of the first detection electrode 33-8 that exhibits the maximum detection value S1 and the detection values ​​S1 of the multiple first detection electrodes 33-5, 33-7, 33-9, and 33-11 that are adjacent to the first detection electrode 33-8 that exhibits the maximum detection value S1. In this way, the second coordinate calculation circuit 54 calculates the distribution (amount of change) of the detection values ​​S1 across the multiple first detection electrodes 33.

[0048] The distribution of the detection values ​​S1 of the multiple first detection electrodes 33 varies depending on the position of the detectable object Fg within the first detection electrode 33-8. For example, when the detectable object Fg is located in the center of the first detection electrode 33-8, the deviation in the detection values ​​S1 of the multiple adjacent first detection electrodes 33-5, 33-7, 33-9, and 33-11 is small. On the other hand, when the detectable object Fg is located on the periphery of the first detection electrode 33-8, the deviation in the detection values ​​S1 of the multiple adjacent first detection electrodes 33-5, 33-7, 33-9, and 33-11 is large. By calculating the distribution of the detection values ​​S1, the second coordinate calculation circuit 54 can calculate the precise detection position of the detectable object Fg within the first detection electrode 33-8 that exhibits the largest detection value S1.

[0049] When the object to be detected Fg (shown in black) is located on the outer edge of the detection area AA (for example, the center of the first detection electrode 33-2), the second coordinate calculation circuit 54 calculates the detection position based on the first detection electrode 33-2 that shows the maximum detection value S1, the detection value S2 of at least one second detection electrode 34-1 adjacent to the first detection electrode 33-2 that shows the maximum detection value S1, and the detection values ​​S1 of the three first detection electrodes 33-1, 33-3, and 33-5.

[0050] 5 is an explanatory diagram for schematically explaining the relationship between the detection values ​​in FIG. 4 and the first and second detection electrodes. When the object to be detected Fg (shown in black) is located on the outer edge of the detection area AA (the center of the first detection electrode 33-2), ideally, the detection value S2 of the second detection electrode 34-1 adjacent to the first detection electrode 33-2 and the detection value S1 of the first detection electrode 33-5 should be equal. However, because the second detection electrode 34 has a different shape (size) from the first detection electrode 33, the capacitance formed between the object to be detected Fg and the second detection electrode 34 is different from the capacitance formed between the object to be detected Fg and the first detection electrode 33. As a result, as shown in FIG. 5, the detection value S2 (S2-1) of the second detection electrode 34-1 is smaller than the detection value S1 (S1-5) of the first detection electrode 33-5.

[0051] The memory circuit 56 stores the first correction amount γs-a as the first correction value γs corresponding to the sensitivity of the second detection electrode 34 when the detectable object Fg is located on the outer edge side of the detection area AA (for example, the center of the first detection electrode 33-2). The first correction amount γs-a is a correction coefficient α set so that the detection value S2 (S2-1) of the second detection electrode 34-1 is equivalent to the detection value S1 (S1-5) of the first detection electrode 33-5. In other words, the value obtained by adding the first correction amount γs-a to the detection value S2 (S2-1) of the second detection electrode 34-1 becomes equivalent to the detection value S1 (S1-5) of the first detection electrode 33-5.

[0052] FIG. 6 is an explanatory diagram for explaining a method for calculating the first correction value of the second detection electrode, and is an explanatory diagram for the case where the object to be detected is located between the first detection electrode and the second detection electrode on the outer edge side of the detection area.

[0053] 6, the detectable object Fg is shifted toward the second detection electrode 34-1 from the state shown in Fig. 4 and is located in the region between the second detection electrode 34-1 and the first detection electrode 33-2. When the detectable object Fg is in the region between the second detection electrode 34-1 and the first detection electrode 33-2 (the region overlapping with the side AAs1 of the detection region AA), the second coordinate calculation circuit 54 calculates the detection position based on the first detection electrode 33-2 exhibiting the maximum detection value S1, the detection value S2 of at least one second detection electrode 34-1 adjacent to the first detection electrode 33-2 exhibiting the maximum detection value S1, and the detection values ​​S1 of the three first detection electrodes 33-1, 33-3, and 33-5.

[0054] Fig. 7 is an explanatory diagram for schematically explaining the relationship between the detection values ​​and the first and second detection electrodes in Fig. 6. Because the object to be detected Fg is shifted toward the second detection electrode 34-1 from the state shown in Fig. 4, as shown in Fig. 7, the detection value S2-1 of the second detection electrode 34-1 is relatively larger than in Fig. 4, and the detection value S1-5 of the first detection electrode 33-5 is relatively smaller than in Fig. 4.

[0055] When the object to be detected Fg is located in the region between the second detection electrode 34-1 and the first detection electrode 33-2, it is ideal that the detection value S1 (S1-2) of the first detection electrode 33-2 and the detection value S2 (S2-1) of the second detection electrode 34-1 adjacent to the first detection electrode 33-2 are equivalent. However, as described above, due to the shape (size) of the second detection electrode 34, the detection value S2 (S2-1) of the second detection electrode 34-1 is smaller than the detection value S1 (S1-2) of the first detection electrode 33-2, as shown in FIG.

[0056] The memory circuit 56 stores the second correction amount γs-b as the first correction value γs corresponding to the sensitivity of the second detection electrode 34 when the detectable object Fg is located on the outer edge side of the detection area AA (for example, in the area between the second detection electrode 34-1 and the first detection electrode 33-2). The second correction amount γs-b is a correction coefficient β that is set so that the detection value S2 (S2-1) of the second detection electrode 34-1 is equivalent to the detection value S1 (S1-2) of the first detection electrode 33-2. In other words, the value obtained by adding the second correction amount γs-b to the detection value S2 (S2-1) of the second detection electrode 34-1 becomes equivalent to the detection value S1 (S1-2) of the first detection electrode 33-2.

[0057] 7, the detection value S2 (S2-1) of the second detection electrode 34-1 is approximately the same as the detection value S1 (S1-5) of the first detection electrode 33-5. However, FIG. 7 is merely an example, and the detection value S2 may be different from the detection value S1 (S1-5).

[0058] The memory circuit 56 stores a first correction value γs corresponding to the sensitivity of the second detection electrode 34. The first correction value γs is a value obtained according to the sensitivity of the second detection electrode 34 based on the first correction amount γs-a (correction coefficient α) described above with reference to FIGS. 4 and 5 and the second correction amount γs-b (correction coefficient β) described above with reference to FIGS. 6 and 7. More specifically, the first correction value γs of the detection value S2 of the second detection electrode 34-1 is determined based on the average value of the first correction amount γs-a (correction coefficient α) of the detection value S2 of the second detection electrode 34 when the detectable object Fg is located in the center of the first detection electrode 33 adjacent to the second detection electrode 34, and the second correction amount γs-b (correction coefficient β) of the detection value S2 of the second detection electrode 34 when the detectable object Fg is located in the region between the second detection electrode 34 and the first detection electrode 33.

[0059] Note that if the correction coefficients α and β differ significantly depending on the shape of the electrodes, weighting may be used instead of averaging. For example, the first correction value γs in the case of averaging can be expressed as γs = Xα + Yβ (X = Y = 0.5), and the first correction value γs in the case of weighting can be expressed as γs = Xα + Yβ (X = 0.6, Y = 0.4). However, values ​​such as X = 0.6 and Y = 0.4 are merely examples, and can be appropriately set depending on the shape of the electrodes, etc.

[0060] When the object to be detected Fg is located on the outer edge side of the detection area AA, the correction circuit 53 can correct the variation in the detection value S2 caused by the shape (size) of the second detection electrode 34 based on the first correction value γs.

[0061] 8 is a graph showing a relationship between the first correction value of the second detection electrode and the height of the object to be detected. The vertical axis of the graph shown in FIG. 8 is the first correction value γs, and the horizontal axis is the height of the object to be detected Fg from the detection surface (for example, the upper surface 111a of the cover member 111 shown in FIG. 2). As described above, the detection device 3 of this embodiment can also perform hover detection, and the first correction value γs has a different value for each height of the object to be detected Fg.

[0062] As shown in FIG. 8, the first correction value γs tends to decrease as the height of the detectable object Fg increases. The memory circuit 56 stores the relationship between the height of the detectable object Fg and the first correction value γs as a correction table for the second detection electrode 34. The memory circuit 56 stores, for example, functions obtained from the relationships between heights of the detectable object Fg of 10 mm, 20 mm, 30 mm, 40 mm, and 50 mm and the respective first correction values ​​γs1, γs2, γs3, γs4, and γs5 as the correction table. The following formula (1) is an example of a function of the first correction value γs. In formula (1), "fs1" is a constant or a function. Furthermore, "S1-max" is the maximum value of the detection value S1 of the first detection electrode 33, and the maximum value S1-max varies depending on the height of the detectable object Fg. That is, the maximum value S1-max includes information about the height of the object to be detected Fg, and by including the maximum value S1-max in equation (1), the first correction value γs according to the height of the object to be detected Fg is obtained.

[0063] γs=fs1 / (S1-max) (1)

[0064] The correction circuit 53 corrects the detection value S2 of the second detection electrode 34 by multiplying the detection value S2 of the second detection electrode 34 by the first correction value γs obtained by the function shown in equation (1). In this way, the correction circuit 53 can correct the variation in the detection value S2 caused by the shape (size) of the second detection electrode 34 and the height of the detection object Fg when the detection object Fg is located on the outer edge side of the detection area AA.

[0065] The memory circuit 56 may store an average value γs-ave of the first correction values ​​γs instead of the function shown in equation (1). The average value γs-ave is, for example, the average value of the first correction values ​​γs1, γs2, γs3, γs4, and γs5 described above. The correction circuit 53 can also correct the detection value S2 of the second detection electrode 34 using the average value γs-ave of the first correction values ​​γs. In this case, the detection device 3 can reduce the amount of calculations performed by the correction circuit 53.

[0066] Next, a description will be given of the correction of the detection value S2 of the second detection electrode 34 due to the position of the detectable object Fg in the extension direction of the second detection electrode 34. Fig. 9 is an explanatory diagram for explaining a method of calculating the second correction value of the second detection electrode 34. Fig. 9 also shows a graph that schematically shows the relationship between the position of the detectable object Fg in the second direction Dy and the detection value S2-1 of the second detection electrode 34-1.

[0067] 9, the second detection electrode 34-1 extends in the second direction Dy along the side AAs1 of the detection area AA. Even if the distance in the first direction Dx between the second detection electrode 34-1 and the detectable object Fg is constant and the height of the detectable object Fg from the detection surface is constant, the detection value S2-1 of the second detection electrode 34-1 varies depending on the position of the detectable object Fg in the extension direction of the second detection electrode 34-1 (the direction indicated by the arrow D1).

[0068] When the object to be detected Fg is located in the center of the extension direction of the second detection electrode 34-1, the detection value S2-1 becomes relatively large, and when the object to be detected Fg is located at the end of the extension direction of the second detection electrode 34-1, the detection value S2-1 becomes relatively small.

[0069] Fig. 10 is a graph schematically illustrating the relationship between the detection value of the second detection electrode in Fig. 9 and the position of the detection object. The horizontal axis of the graph shown in Fig. 10 represents the position of the detection object Fg in the second direction Dy, and shows a case where the detection object Fg is located at the center of each of the first detection electrodes 33-1, 33-2, and 33-3. The vertical axis of the graph shown in Fig. 10 represents the detection value S2-1 of the second detection electrode 34-1. For comparison, Fig. 10 also shows the detection value S1-5 of the first detection electrode 33-5, which is adjacent to the first detection electrode 33-1 on the opposite side of the second detection electrode 34-1.

[0070] 10, the memory circuit 56 stores a third correction amount γp-a as a second correction value γp for the detection value S2 of the second detection electrode 34 according to the position of the detectable object Fg in the second direction Dy. The third correction amount γp-a is set so that the detection value S2 (S2-1) of the second detection electrode 34-1 remains constant even when the position of the detectable object Fg in the extension direction of the second detection electrode 34-1 varies. In other words, the value obtained by adding the third correction amount γp-a to the detection value S2 (S2-1a) of the second detection electrode 34-1 when the detectable object Fg is located at an end of the extension direction of the second detection electrode 34-1 (first detection electrodes 33-1, 33-3) is equivalent to the detection value S2 (S2-1) of the second detection electrode 34-1 when the detectable object Fg is located at the center of the extension direction of the second detection electrode 34-1 (first detection electrode 33-2).

[0071] 4 to 8, the memory circuit 56 also stores the second correction value γp corresponding to the position of the detectable object Fg in the extension direction of the second detection electrode 34-1 as a correction value for the detection value S2 of the second detection electrode 34. Using the second correction value γp, the correction circuit 53 can correct variations in the detection value S2 resulting from the position of the detectable object Fg in the extension direction of the second detection electrode 34 when the detectable object Fg is located on the outer edge side of the detection area AA.

[0072] Fig. 11 is a graph schematically showing the relationship between the second correction value of the second detection electrode and the height of the object to be detected. The vertical axis of the graph shown in Fig. 11 is the second correction value γp, and the horizontal axis is the height of the object to be detected Fg from the detection surface (for example, the upper surface 111a of the cover member 111 shown in Fig. 2). As in the example shown in Fig. 8, the second correction value γp has a different value for each height of the object to be detected Fg.

[0073] As shown in FIG. 11, the second correction value γp tends to increase as the height of the detectable object Fg increases. The memory circuit 56 stores the relationship between the height of the detectable object Fg and the second correction value γp as a correction table for the second detection electrode 34. The memory circuit 56 stores, as a correction table, functions obtained from the relationships between the heights of the detectable object Fg of 10 mm, 20 mm, 30 mm, 40 mm, and 50 mm and the respective second correction values ​​γp1, γp2, γp3, γp4, and γp5. The following formula (2) is an example of a function of the second correction value γp. Here, "fp1" is a constant or a function. Note that, like the above-described formula (1), formula (2) includes a maximum value S1-max, thereby obtaining a second correction value γp according to the height of the detectable object Fg.

[0074] γp=fp1 / (S1-max) (2)

[0075] The correction circuit 53 corrects the detection value S2 of the second detection electrode 34 by multiplying the detection value S2 of the second detection electrode 34 by the second correction value γp obtained by the function shown in equation (2). In this way, the correction circuit 53 can correct variations in the detection value S2 caused by the position of the detectable object Fg in the extension direction of the second detection electrode 34 and the height of the detectable object Fg when the detectable object Fg is located on the outer edge side of the detection area AA.

[0076] The memory circuit 56 may store an average value γp-ave of the second correction values ​​γp instead of the function shown in equation (2). The average value γp-ave is, for example, the average value of the second correction values ​​γp1, γp2, γp3, γp4, and γp5 described above. The correction circuit 53 can also correct the detection value S2 of the second detection electrode 34 using the average value γp-ave of the second correction values ​​γp. In this case, the amount of calculation by the correction circuit 53 can be reduced.

[0077] Fig. 12 is a table showing an example of a correction table for the detection value of the second detection electrode. Fig. 13 is a table showing an example of a correction table for the detection value of the second detection electrode. The memory circuit 56 stores the first correction value γs and the second correction value γp of the detection value S2 of the second detection electrode 34 described above as the correction tables shown in Figs. 12 and 13.

[0078] The correction table shown in Fig. 12 shows the first correction value γs and the second correction value γp when the detectable object Fg is located along the sides AAs1 and AAs2 on the outer edge of the detection area AA. The correction table shown in Fig. 13 shows the first correction value γs and the second correction value γp when the detectable object Fg is located along the sides AAs3 and AAs4 on the outer edge of the detection area AA.

[0079] As shown in FIGS. 12 and 13, the correction table sets a first correction value γs and a second correction value γp for each combination of the object to be detected Fg (i.e., the first detection electrode 33 that shows the peak of the detection value S1) and the second detection electrode 34 to be corrected. The first correction value γs and the second correction value γp are functions similar to the above-mentioned formulas (1) and (2), respectively. In the first correction value γs and the second correction value γp, "fs1" to "fs4" and "fp1" to "fp4" are constants or functions, respectively. Furthermore, "S1-1(max)" to "S1-15(max)" are the maximum values ​​of the detection value S1 of the first detection electrode 33, and contain information about the height of the object to be detected Fg.

[0080] 12 and 13 according to the position of the detectable object Fg and the second detection electrode 34 to be corrected, and corrects the detection value S2 of the second detection electrode 34. In this way, the correction circuit 53 can correct the variation in the detection value S2 caused by the shape (size) of the second detection electrode 34 when the detectable object Fg is located on the outer edge side of the detection area AA, the variation in the detection value S2 caused by the position of the detectable object Fg in the extension direction of the second detection electrode 34, and the variation in the detection value S2 caused by the height of the detectable object Fg.

[0081] When the detectable object Fg is located on the outer edge side of the detection area AA, the second coordinate calculation circuit 54 calculates the position of the detectable object Fg based on a value obtained by multiplying the detection value S2 of at least one second detection electrode 34 by the first correction value γs and the second correction value γp (hereinafter referred to as the corrected detection value S2). Specifically, the second coordinate calculation circuit 54 calculates the detection position based on the first detection electrode 33 exhibiting the maximum detection value S1, the corrected detection value S2 of at least one second detection electrode 34 adjacent to the first detection electrode 33 exhibiting the maximum detection value S1, and the detection values ​​S1 of at least two first detection electrodes 33. This makes it possible to calculate the precise position of the detectable object Fg within the first detection electrode 33 exhibiting the maximum detection value S1.

[0082] For example, if the detectable object Fg is located on the outer edge of the detection area AA and in the center of the first detection electrode 33-2, the second coordinate calculation circuit 54 calculates the detection position of the detectable object Fg based on the first detection electrode 33-2 exhibiting the maximum detection value S1, the corrected detection value S2 of the second detection electrode 34-1 adjacent to the first detection electrode 33-2, and the detection values ​​S1 of the three first detection electrodes 33-1, 33-3, and 33-5. Also, if the detectable object Fg is located at a corner of the detection area AA and in the center of the first detection electrode 33-1, the second coordinate calculation circuit 54 calculates the detection position of the detectable object Fg based on the first detection electrode 33-1 exhibiting the maximum detection value S1, the corrected detection values ​​S2 of the two second detection electrodes 34-1 and 34-3 adjacent to the first detection electrode 33-1, and the detection values ​​S1 of the two first detection electrodes 33-2 and 33-4.

[0083] Next, a detection method of the detection device 3 of this embodiment will be described. Fig. 14 is a flowchart for explaining the detection method of the detection device according to this embodiment. As shown in Fig. 14, the detection device 3 drives the first detection electrode 33 and the second detection electrode 34 in a state where the object to be detected Fg is not present on the detection surface, and detects a baseline (step ST1). The memory circuit 56 (see Fig. 3) stores the baseline detected based on the detection values ​​S1, S2 of the first detection electrode 33 and the second detection electrode 34.

[0084] Next, the detection device 3 drives the first detection electrodes 33 and the second detection electrodes 34 to perform touch detection (step ST2). The detection circuit 40 (see FIG. 3) performs the various signal processes described above on the detection signals Vdet1 and Vdet2 from the first detection electrodes 33 and the second detection electrodes 34, and transmits detection values ​​S1 and S2 to the host 50. The first coordinate calculation circuit 52 of the host 50 calculates the difference between the detection values ​​S1 and S2 from the detection circuit 40 and the baseline.

[0085] The determination circuit 55 compares the detection value S1 of the first detection electrode 33 with a preset threshold value to determine whether the detection value S1 is equal to or greater than the threshold value (step ST3). If the detection value S1 is smaller than the threshold value (step ST3, No), the determination circuit 55 determines that the object to be detected Fg is not in contact with or in proximity to the detection surface, and performs touch detection in step ST2.

[0086] If the detection value S1 is equal to or greater than the threshold value (step ST3, Yes), the determination circuit 55 determines that the object to be detected Fg is in contact with or in proximity to the detection surface, and then determines whether the object to be detected Fg is located within the detection area AA (step ST4).

[0087] Here, an example of a method for determining whether a detectable object Fg is located within the detection area AA will be described with reference to Fig. 15 and Fig. 16. Fig. 15 is an explanatory diagram for explaining a method for detecting a detectable object using the second detection electrode, and is an explanatory diagram for explaining a case where the detectable object is located in the detection area. Fig. 16 is an explanatory diagram for explaining a method for detecting a detectable object using the second detection electrode, and is an explanatory diagram for explaining a case where the detectable object is located in the peripheral area.

[0088] 15 and 16 schematically show the magnitude of the detection value S2 output from each of the second detection electrodes 34. The magnitude of the detection value S2 is, for example, a voltage value, and the greater the number of blocks of the detection value S2 shown in FIGS. 15 and 16, the greater the voltage value of the detection value S2.

[0089] 15 illustrates a case where the detectable object Fg is within the detection area AA, specifically, where the detectable object Fg is located in the area overlapping with the first detection electrode 33-8 at the center of the detection area AA. As shown in FIG. 15, when the detectable object Fg is within the detection area AA, the detection values ​​S2-1 and S2-2 from the two second detection electrodes 34-1 and 34-2, which are arranged on either side of the detectable object Fg in the first direction Dx, are approximately equal. Similarly, the detection values ​​S2-3 and S2-4 from the two second detection electrodes 34-3 and 34-4, which are arranged on either side of the detectable object Fg in the second direction Dy, are approximately equal. Depending on the distance from the detectable object Fg, the detection values ​​S2-3 and S2-4 from the second detection electrodes 34-3 and 34-4 are greater than the detection values ​​S2-1 and S2-2 from the second detection electrodes 34-1 and 34-2.

[0090] FIG. 16 illustrates a case where the detectable object Fg is located in the peripheral region BE, specifically, a case where the detectable object Fg is located closer to the outer edge of the substrate 31 than the side AAs1 of the detection region AA and the second detection electrode 34-1. As shown in FIG. 16, when the detectable object Fg is located in the peripheral region BE, the detection values ​​S2-3 and S2-4 from the two second detection electrodes 34-3 and 34-4, which are disposed on either side of the detection region AA in the second direction Dy, are approximately equal in magnitude. Meanwhile, the detection value S2-1 from the second detection electrode 34-1, which is closer to the detectable object Fg in the first direction Dx, is different from the detection value S2-2 from the second detection electrode 34-2, which is farther from the detectable object Fg across the detection region AA. The detection value S2-1 from the second detection electrode 34-1 is greater than the detection values ​​S2-3 and S2-4 from the second detection electrodes 34-3 and 34-4 depending on the distance from the detectable object Fg. Furthermore, the detection value S2-2 of the second detection electrode 34-2 is smaller than the detection values ​​S2-3 and S2-4 of the second detection electrodes 34-3 and 34-4.

[0091] 15 and 16, the distribution of the detection values ​​S2 of the second detection electrode 34 differs depending on whether the detectable object Fg is in the detection area AA or the peripheral area BE. When the detectable object Fg is in the detection area AA, the deviation of the detection values ​​S2 is small, and when the detectable object Fg is in the peripheral area BE, the deviation of the detection values ​​S2 is large.

[0092] The detection device 3 measures in advance the distribution of the detection values ​​S2 for each position of the detectable object Fg, and the memory circuit 56 stores the distribution patterns of these detection values ​​S2 in a table. In step ST4 shown in FIG. 14, the determination circuit 55 determines whether the detectable object Fg is located within the detection area AA by comparing the distribution patterns of the detection values ​​S2 of the second detection electrodes 34. As described above, the detection device 3 has the determination circuit 55 that determines whether the detectable object Fg is in contact with or in proximity to the first detection electrodes 33 and the at least one second detection electrode 34 based on the detection values ​​S1 and S2 of the first detection electrodes 33 and the at least one second detection electrode 34. When the detection value S2 of the second detection electrode 34 is the largest among the detection values ​​S1 and S2 of the first detection electrodes 33 and the at least one second detection electrode 34, the determination circuit 55 determines that the detectable object Fg is located within the peripheral area BE.

[0093] 15 and 16, whether or not the detectable object Fg is within the detection area AA is determined based on the detection value S2 of the second detection electrode 34, but this is not limiting. Whether or not the detectable object Fg is within the detection area AA may be determined using not only the detection value S2 of the second detection electrode 34 but also the detection value S1 of the first detection electrode 33.

[0094] Returning to FIG. 14, if the detectable object Fg is not within the detection area AA (No at step ST4), the detection device 3 determines that the input operation is not by the detectable object Fg, and repeats the touch detection at step ST2.

[0095] If the detectable object Fg is within the detection area AA (step ST4, Yes), the detection device 3 determines that an input operation has been performed using the detectable object Fg. The first coordinate calculation circuit 52 detects the peak positions of the detection values ​​S1 of the multiple first detection electrodes 33 (step ST5). In step ST5, approximate position information of the detectable object Fg is obtained from information on the peak position of the detection value S1, and height information of the detectable object Fg is obtained from the magnitude of the peak of the detection value S1.

[0096] The determination circuit 55 determines whether the peak position is on the outer edge side of the detection area AA (step ST6) based on the information on the peak position of the detection value S1 calculated by the first coordinate calculation circuit 52. If the peak position is on the outer edge side of the detection area AA (step ST6, Yes), the determination circuit 55 determines the peak position of the detection value S1 in more detail in order to select the second detection electrode 34 to be corrected.

[0097] Specifically, the determination circuit 55 determines whether the peak position of the detection value S1 is on the outer edge side of the detection area AA in the first direction Dx (step ST7). If the peak position of the detection value S1 is on the outer edge side of the detection area AA in the first direction Dx (step ST7, Yes), for example, in the example shown in FIG. 4, if the peak position of the detection value S1 is on any of the first detection electrodes 33-1, 33-2, 33-3, 33-13, 33-14, and 33-15, the correction circuit 53 corrects the detection value S2 of the second detection electrode 34-1 or 34-2 (step ST8).

[0098] If the peak position of the detection value S1 is not on the outer edge side of the detection area AA in the first direction Dx (step ST7, No), the correction circuit 53 does not correct the detection value S2 of the second detection electrodes 34-1 and 34-2.

[0099] Next, the determination circuit 55 determines whether the peak position of the detection value S1 is on the outer edge side of the detection area AA in the second direction Dy (step ST9). If the peak position of the detection value S1 is on the outer edge side of the detection area AA in the second direction Dy (step ST9, Yes), for example, in the example shown in Fig. 4, if the peak position of the detection value S1 is one of the first detection electrodes 33-1, 33-4, 33-7, 33-10, 33-13, 33-3, 33-6, 33-9, 33-12, and 33-15, the correction circuit 53 corrects the detection value S2 of the second detection electrode 34-3 or 34-4 using, for example, the correction table shown in Fig. 13 (step ST10).

[0100] If the peak position of the detection value S1 is not on the outer edge side of the detection area AA in the second direction Dy (step ST9, No), the correction circuit 53 does not correct the detection value S2 of the second detection electrodes 34-3 and 34-4.

[0101] The second coordinate calculation circuit 54 extracts the detection values ​​S1 of the multiple first detection electrodes 33 adjacent to the first detection electrode 33 at the peak position and the detection value S2 of at least one second detection electrode 34 (step ST11). The second coordinate calculation circuit 54 calculates the position of the detectable object Fg based on the multiple detection values ​​S1 and the corrected detection value S2 extracted in step ST11 (step ST12). In this way, when the detectable object Fg is located on the outer edge side of the detection area AA, the second coordinate calculation circuit 54 calculates the position of the detectable object Fg using the corrected detection value S2. Specifically, the second coordinate calculation circuit 54 calculates the distribution of the detection values ​​S1 and the corrected detection value S2 across the multiple first detection electrodes 33 and at least one second detection electrode 34, thereby enabling the position of the detectable object Fg within the first detection electrode 33 that indicates the peak of the detection value S1 to be accurately detected.

[0102] Returning to step ST6, if the peak position of the detection value S1 is not on the outer edge side of the detection area AA (step ST6, No), in other words, if the peak position of the detection value S1 is in the center of the detection area AA, the correction circuit 53 does not correct the detection value S2 of the second detection electrode 34 as shown in steps ST7 to ST10.

[0103] The second coordinate calculation circuit 54 extracts the detection values ​​S1 of the multiple first detection electrodes 33 adjacent to the first detection electrode 33 at the peak position (step ST11). The second coordinate calculation circuit 54 calculates the position of the object to be detected Fg based on the multiple detection values ​​S1 extracted in step ST11 (step ST12). In this way, the second coordinate calculation circuit 54 calculates the distribution of the detection values ​​S1 across the multiple first detection electrodes 33, thereby enabling the second coordinate calculation circuit 54 to accurately detect the position of the object to be detected Fg within the first detection electrode 33 that indicates the peak of the detection value S1.

[0104] 14 is merely an example and can be modified as appropriate. For example, the order of steps ST7 and ST8 and steps ST9 and ST10 may be reversed. Furthermore, steps ST7 and ST8 and steps ST9 and ST10 are described separately for ease of explanation, but these steps may also be performed simultaneously.

[0105] (First Modification) 17 is a plan view schematically showing a detection device according to Modification 1. In the following description, the same components as those described in the above embodiment are denoted by the same reference numerals, and redundant description will be omitted.

[0106] As shown in FIG. 17 , in the detection device 3A according to the first modification, six second detection electrodes 34 are arranged surrounding the detection area AA and the plurality of first detection electrodes 33. Specifically, the second detection electrodes 34-3 and 34-5 are arranged side by side in the first direction Dx along the side AAs3 of the detection area AA. The second detection electrodes 34-3 and 34-5 are arranged separated by a slit. Similarly, the second detection electrodes 34-4 and 34-6 are arranged side by side in the first direction Dx along the side AAs4 of the detection area AA. The second detection electrodes 34-4 and 34-6 are arranged separated by a slit. The detection area AA and the plurality of first detection electrodes 33 are arranged between the second detection electrodes 34-3 and 34-5 and the second detection electrodes 34-4 and 34-6, which are adjacent to each other in the second direction Dy. The second detection electrodes 34-1 and 34-2 are similar to those in the above-described embodiment, and a repeated description will be omitted.

[0107] (Second Modification) FIG. 18 is a plan view schematically illustrating a detection device according to a second modification. As shown in FIG. 18, in the detection device 3B according to the second modification, eight second detection electrodes 34 are arranged surrounding a detection area AA and a plurality of first detection electrodes 33. Specifically, the second detection electrodes 34-1 and 34-7 are arranged side by side in the second direction Dy along a side AAs1 of the detection area AA. The second detection electrodes 34-1 and 34-7 are arranged separated by a slit. Similarly, the second detection electrodes 34-2 and 34-8 are arranged side by side in the second direction Dy along a side AAs2 of the detection area AA. The second detection electrodes 34-2 and 34-8 are arranged separated by a slit. The detection area AA and a plurality of first detection electrodes 33 are arranged between the second detection electrodes 34-1 and 34-7 and the second detection electrodes 34-2 and 34-8, which are adjacent to each other in the first direction Dx. The second detection electrodes 34-3, 34-4, 34-5, and 34-6 are the same as those in the first modified example, and a repeated description will be omitted.

[0108] As shown in the first and second modified examples, by increasing the number of second detection electrodes 34 (increasing the number of divisions), the detection value S2 of the second detection electrodes 34 can be corrected with high accuracy, and the detection accuracy on the outer edge side of the detection area AA can be improved. Also, in the first and second modified examples, the number of second detection electrodes 34 can be increased within a range in which the time constant of the plurality of second detection electrodes 34 is equivalent to the time constant of the plurality of first detection electrodes 33.

[0109] (Third Modification) Fig. 19 is a plan view schematically showing a detection device according to a third modified example. As shown in Fig. 19, a detection device 3C according to the third modified example further includes a shield electrode AS. The shield electrode AS is provided in the peripheral region BE of the substrate 31, surrounding the plurality of first detection electrodes 33 and the plurality of second detection electrodes 34. In the example shown in Fig. 19, the shield electrode AS is formed in the shape of a single continuous frame. However, this is not limiting, and a slit or the like may be provided in part of the shield electrode AS, or the shield electrode AS may be divided into multiple shield electrodes AS.

[0110] The shield electrode AS is supplied with a signal having the same phase as the drive signal supplied to the plurality of first detection electrodes 33 and the plurality of second detection electrodes 34. In addition, the shield electrode AS is supplied with a signal having the same amplitude as the drive signal supplied to the plurality of first detection electrodes 33 and the plurality of second detection electrodes 34. This makes it possible to suppress parasitic capacitance formed in the plurality of first detection electrodes 33 and the plurality of second detection electrodes 34.

[0111] Although preferred embodiments of the present invention have been described above, the present invention is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible without departing from the spirit of the present invention. Appropriate modifications made without departing from the spirit of the present invention naturally fall within the technical scope of the present invention. At least one of various omissions, substitutions, and modifications of components can be made without departing from the spirit of each of the above-described embodiments and modifications. [Explanation of symbols]

[0112] 1. Display device with detection device 2 Display panel 3, 3A, 3B, 3C detection device 10 Sensor section 31 PCB 33 First detection electrode 34, 34-1, 34-2, 34-3, 34-4, 34-5, 34-6, 34-7, 34-8 Second detection electrode 40 Detection circuit 50 hosts 52 First coordinate calculation circuit 53 Correction circuit 54 Second coordinate calculation circuit 55 Judgment circuit 56 Memory circuit AA detection area AS Shield Electrode BE peripheral area Fg Object to be detected S1, S2 detection value γs, γs1, γs2, γs3, γs4, γs5 First correction value γp, γp1, γp2, γp3, γp4, γp5 Second correction value

Claims

1. a plurality of first detection electrodes arranged in a matrix in a detection region of the substrate; a plurality of second detection electrodes arranged in a peripheral region outside the detection region, adjacent to the plurality of first detection electrodes, and provided along sides of the detection region; a coordinate calculation circuit for calculating the detected position of the object to be detected; a shield electrode provided in the peripheral region and surrounding the first detection electrodes and the second detection electrodes; In a plan view, an inner edge of the shield electrode is disposed outward from outer edges of the plurality of second detection electrodes. Detection device.

2. The plurality of first detection electrodes and the plurality of second detection electrodes output detection signals according to changes in their respective self-capacitances. The detection device according to claim 1 .

3. The width of the second detection electrode is smaller than the width of the first detection electrode in a direction intersecting with the extension direction of the second detection electrode. The detection device according to claim 1 or 2.

4. The time constants of the second detection electrodes are substantially equal to the time constants of each of the first detection electrodes. The detection device according to any one of claims 1 to 3.

5. The shield electrode is supplied with a signal in phase with the first detection electrodes and the second detection electrodes. The detection device according to any one of claims 1 to 4.

6. The shield electrode is supplied with a signal having the same amplitude as the first detection electrodes and the second detection electrodes. The detection device according to any one of claims 1 to 5.

7. a memory circuit that stores a first correction value according to the sensitivity of the plurality of second detection electrodes; The coordinate calculation circuit calculates the detected position of the object to be detected based on a value obtained by multiplying the detection values ​​of the plurality of second detection electrodes by the first correction value. The detection device according to any one of claims 1 to 6.

8. The first correction value is determined based on an average value of a first correction amount for the detection value of the second detection electrode when the object to be detected is located in the center of the first detection electrode adjacent to the second detection electrode, and a second correction amount for the detection value of the second detection electrode when the object to be detected is located in a region between the second detection electrode and the first detection electrode. The detection device according to claim 7.

9. the first correction value has a different value for each height of the detection object, The memory circuit stores the relationship between the height of the object to be detected and the first correction value as a correction table for the second detection electrode.

9. The detection device according to claim 7 or claim 8.

10. the second detection electrodes extend along the sides of the detection area; The memory circuit stores a second correction value for the detection value of the second detection electrode according to the position of the object to be detected in the extension direction of the second detection electrode. The detection device according to any one of claims 7 to 9.

11. the second correction value has a different value for each height of the object to be detected, The memory circuit stores the relationship between the height of the object to be detected and the second correction value as a correction table for the second detection electrode. The detection device according to claim 10.

12. a determination circuit for determining whether or not the object to be detected is in contact with or in proximity to the object based on detection values ​​of the plurality of first detection electrodes and the plurality of second detection electrodes; When the detection value of the second detection electrode indicates a maximum value among the detection values ​​of the plurality of first detection electrodes and the plurality of second detection electrodes, the determination circuit determines that the object to be detected is in the peripheral region. Detecting device according to any one of claims 1 to 11.

13. In a plan view, the shield electrode and the plurality of second detection electrodes do not have overlapping portions with each other. Detecting device according to any one of claims 1 to 12.

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