Electronic devices

Abstract

The electronic device (10) comprises: a differential amplifier (30) for amplifying and outputting the difference between a positive signal and a negative signal selectively output from a plurality of electrodes (20) included in a touch sensor (14); and a conductive component (56) made of a conductive material or including a conductive material, arranged in a manner that partially overlaps with a sensor region (R) formed by the touch sensor (14) in a plan view. The conductive component (56) is arranged in a manner that the outermost end point (62) in the arrangement direction is located on any one of the plurality of electrodes (20).

Description

Technical Field

[0001] The invention relates to an electronic device, a touch sensor and a position detection device. Background Art

[0002] Patent Document 1 discloses a position detection device of a so-called "differential amplifier method" that amplifies and outputs the difference between the signal of the positive electrode and the signal of the negative electrode of the touch sensor. By obtaining the difference of the signals from two parallel electrodes, the common mode noise generated in the same direction can be eliminated.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 8-095701 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In addition to the touch sensor, a component made of or containing a conductive material (hereinafter referred to as a conductive component) is installed inside the electronic device. By generating electromagnetic interference with the conductive component, common mode noise is sometimes mixed into the detection signal of the touch sensor. Usually, the conductive component has a size smaller than the sensor area formed by the touch sensor, and is configured in a manner that partially overlaps with the sensor area when viewed from above. Therefore, the size of the noise contained in the detection signal may vary depending on the position in the sensor area.

[0008] However, in the differential amplification method as disclosed in Patent Document 1, when the magnitudes of noise mixed into the signal of the positive electrode and the signal of the negative electrode are different, the common mode noise cancellation effect cannot be obtained, and the influence of noise due to amplification becomes larger.

[0009] An object of the present invention is to provide an electronic device that can further demonstrate the noise canceling effect of a differential amplifier system by taking into account the relationship with a conductive component that may become a source of noise.

[0010] Means for solving problems

[0011] The electronic device in the first present invention comprises: a touch sensor, which is constructed to include a plurality of electrodes separated from each other and arranged in a planar shape along an arrangement direction; a differential amplifier, which amplifies and outputs the difference between the positive side signal and the negative side signal selectively output from the plurality of electrodes; a position detection unit, which detects the touch position within the sensor area formed by the touch sensor based on the output signal from the differential amplifier; and a conductive component, which is a component composed of or including a conductive material, and is configured in a manner that partially overlaps with the sensor area when viewed from above, and the conductive component is configured in a manner that the outermost end point in the arrangement direction is located on any one of the plurality of electrodes.

[0012] The touch sensor in the second present invention is a sensor used with a display panel, which drives multiple pixels by applying a driving voltage to matrix signal lines arranged in the row direction and the column direction, and can display an image or video in the display area, wherein the touch sensor is configured in a manner that at least partially overlaps with the display area when viewed from above, and is constructed to include multiple electrodes arranged in a rectangular shape, the multiple electrodes including: multiple first electrodes extending in a first direction and arranged separately from each other along a direction orthogonal to the first direction; and multiple second electrodes extending in a second direction intersecting the first direction and arranged separately from each other along a direction orthogonal to the second direction, and at least one of the first direction and the second direction is inclined relative to both the row direction and the column direction.

[0013] A position detection device according to a third aspect of the present invention includes: the touch sensor according to the second aspect of the present invention; and a position detection unit configured to detect a touch position within a sensor area formed by the touch sensor based on a detection signal from the touch sensor.

[0014] Effects of the Invention

[0015] According to the first present invention, the noise canceling effect of the differential amplifier method can be further exerted by taking into account the relationship with the conductive member that may become a source of noise.

[0016] According to the second and third present inventions, it is possible to suppress the common mode noise caused by the electrical interference with the display panel from being mixed into the detection signal of the touch sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a circuit configuration diagram related to the position detection function of the electronic device in the first embodiment of the present invention.

[0018] Figure 2 yes Figure 1 An exploded perspective view of the electronic device shown.

[0019] Figure 3 It is shown Figure 2 The diagram shows the relative positional relationship among the main substrate, display panel and touch sensor.

[0020] Figure 4 yes Figure 3 Enlarged view of part A.

[0021] Figure 5 yes Figure 3 Enlarged view of part B.

[0022] Fig. 6A It is shown Figure 4 Figure 2 shows another structure of the heat sink.

[0023] Figure 6B It is shown Figure 4 Figure 2 shows another structure of the heat sink.

[0024] Figure 7 is shown with Figure 4 The corresponding figure is that of the comparative example.

[0025] Figure 8 It is shown by Figure 4 A diagram showing the effect achieved by the configuration relationship.

[0026] Fig. 9 It is a circuit configuration diagram related to the position detection function of the electronic device in the second embodiment of the present invention.

[0027] Fig.10 yes Fig. 9 An exploded perspective view of the electronic device shown.

[0028] Fig.11 It is shown Fig.10 A diagram showing the structure of a driving circuit included in a display panel.

[0029] Fig. 12A This is a schematic diagram related to the line inversion driving method.

[0030] Fig. 12B This is a schematic diagram related to the line inversion driving method.

[0031] Fig.13 yes Fig. 9 A partial enlarged view of the first electrode shown.

[0032] Fig.14 yes Fig. 9 and Fig.10 A top view of the touch sensor is shown.

[0033] Fig.15A It is explaining that Fig.14A diagram of a comparative example is shown when the touch sensor achieves the first effect.

[0034] Fig. 15B It is explaining that Fig.14 A diagram of an embodiment is shown when a first effect of a touch sensor is achieved.

[0035] Fig.16A It is explaining that Fig.14 A diagram of a comparative example is shown when the second effect achieved by the touch sensor is shown.

[0036] Fig. 16B It is explaining that Fig.14 A diagram of an embodiment showing a second effect achieved by a touch sensor. DETAILED DESCRIPTION

[0037] Hereinafter, preferred embodiments of the electronic device, touch sensor, and position detection device of the present invention will be described with reference to the accompanying drawings. Figure 1 It should be noted that the present invention is not limited to the following embodiments and modifications, and can be freely changed within the scope of the present invention. Alternatively, the various structures can be arbitrarily combined within the scope that does not cause technical contradictions.

[0038] [First embodiment]

[0039] Hereinafter, with reference to the electronic device in the first embodiment of the present invention, Figures 1 to 8 While explaining.

[0040] <Circuit Structure of Electronic Device 10>

[0041] Figure 1 1 is a circuit structure diagram related to the position detection function of the electronic device 10 in the first embodiment of the present invention. The electronic device 10 is composed of, for example, a tablet terminal, a smart phone, or a personal computer. The user can write pictures and texts on the electronic device 10 by holding the electronic pen 12 and moving the pen tip against the touch surface of the electronic device 10. The electronic pen 12 is, for example, an active electrostatic (AES) or electromagnetic induction (EMR) stylus.

[0042] Specifically, the electronic device 10 includes a touch sensor 14 for detecting the proximity of a conductive object such as the electronic pen 12 or a user's finger, an integrated circuit (IC: Integrated Circuit; hereinafter, touch IC 16 ) for controlling the touch sensor 14 , and a host processor 18 electrically connected to the touch IC 16 .

[0043] The touch sensor 14 is overlapped with the display panel 44 ( Figure 2) electrostatic capacitance type sensor. The touch sensor 14 may be a mutual capacitance type sensor or a self capacitance type sensor. The touch sensor 14 is configured to include a plurality of electrodes 20 that are separated from each other and arranged in a planar shape along an arrangement direction. The material of the electrode 20 may be indium tin oxide (ITO) or a metal such as copper, silver, or gold.

[0044] The linear or strip-shaped electrode 20 includes a first electrode 21 for detecting a position in the X direction (X coordinate) and a second electrode 22 for detecting a position in the Y direction (Y coordinate). The first electrode 21 and the second electrode 22 are insulated by being sandwiched by an insulating substrate (not shown) made of glass or resin. A plurality of first electrodes 21 are extended in the Y direction, and are separated from each other and arranged at equal intervals along the X direction. A plurality of second electrodes 22 are extended in the X direction, and are separated from each other and arranged at equal intervals along the Y direction. That is, the X direction and the Y direction shown in this figure are equivalent to the X axis and the Y axis of the "sensor coordinate system" defined in the sensor area As formed by the touch sensor 14. In this first embodiment, the sensor coordinate system is the same as the sensor coordinate system on the display panel 44 ( Figure 2 ) is consistent with the "display coordinate system" defined in the display area formed.

[0045] The touch IC 16 includes an X selection circuit 24 , a Y selection circuit 26 , a switch 28 , a differential amplifier 30 , a bandpass filter (hereinafter referred to as a BP filter 32 ), a detection circuit 34 , an AD converter 36 , and a microprocessor unit (hereinafter referred to as an MCU 38 ).

[0046] The X selection circuit 24 is a multiplexer connected to the plurality of first electrodes 21. The X selection circuit 24 selects two electrodes from the plurality of first electrodes 21 according to the instruction signal from the MCU 38, and outputs two types of signals (X positive side signal and X negative side signal) from each electrode at the same time. The Y selection circuit 26 is a multiplexer connected to the plurality of second electrodes 22. The Y selection circuit 26 selects two electrodes from the plurality of second electrodes 22 according to the instruction signal from the MCU 38, and outputs two types of signals (Y positive side signal and Y negative side signal) from each electrode at the same time.

[0047] The switch 28 is connected to the output sides of the X selection circuit 24 and the Y selection circuit 26, respectively. The switch 28 selectively outputs either the positive side signal or the negative side signal according to the command signal from the MCU 38. The differential amplifier 30 amplifies the difference between the positive side signal and the negative side signal selectively output from the plurality of electrodes 20 through the switch 28 and outputs the amplified difference.

[0048] BP filter 32 is a filter circuit that passes a predetermined frequency band centered on a frequency corresponding to an output signal from electronic pen 12. Detection circuit 34 is a circuit that generates a detection signal based on the output signal that has passed BP filter 32. AD converter 36 is a signal converter that converts an analog signal into a digital signal.

[0049] MCU38 is a device capable of detecting a touch position in the sensor area As by processing the digital signal output from the AD converter 36. MCU38 reads and executes a position detection program from a memory (not shown) to realize a "pen detection function" for detecting the state of the electronic pen 12 and a "touch detection function" for detecting a touch of a user's finger or the like.

[0050] The pen detection function includes, for example, a scanning function (global scanning or sector scanning) of the touch sensor 14, a reception and analysis function of a downlink signal, a function of estimating the state of the electronic pen 12 (e.g., position, posture, pen pressure), and a function of generating and transmitting an uplink signal including a command to the electronic pen 12. In addition, the touch detection function includes, for example, a scanning function of the touch sensor 14, a function of creating a detection map (two-dimensional distribution of detection levels) within the sensor area As, and a function of classifying areas on the detection map (e.g., classification into fingers, palms, etc.).

[0051] The host processor 18 is composed of a processing and calculation device including a CPU (Central Processing Unit), an MPU (Micro-Processing Unit), and a GPU (Graphics Processing Unit). The host processor 18 can perform various functions including the generation of digital ink, the creation of image signals, and the control of data transmission and reception by reading and executing a program stored in a memory (not shown).

[0052] <Device Structure of Electronic Device 10>

[0053] Figure 2 yes Figure 1 An exploded perspective view of the electronic device 10 is shown. Figure 3 It is shown Figure 24, and the display panel 44. The electronic device 10 is formed by stacking a back cover 40, a main substrate 42, a display panel 44, a touch sensor 14, and a front cover 46 in order from the back side. In the example of this figure, the touch sensor 14 is an "external type" sensor mounted from the outside to the display panel 44, but it can also be replaced by a "built-in type" (if further classified, it is an on-cell type or in-cell type) sensor that is integrally formed with the display panel 44.

[0054] The rear cover 40 and the front cover 46 are members constituting a housing for accommodating electronic components in the electronic device 10. The front cover 46 is provided with a highly light-transmitting protective panel 48 so as to cover the entire opening formed on the main surface thereof.

[0055] The display panel 44 is composed of, for example, a liquid crystal panel, an organic EL (Electro Luminescence) panel, electronic paper, etc. The display panel 44 drives a plurality of pixels by applying a driving voltage to matrix signal lines arranged in row and column directions, thereby displaying an image or video in a display area.

[0056] The main substrate 42 is a substrate that constitutes a circuit for operating the electronic device 10. Figure 3 As shown, on the main substrate 42, in addition to the above-mentioned touch IC 16 and host processor 18, a connector 50 and various electronic components 52 are also arranged. The connector 50 is configured to be able to electrically connect the flexible printed circuit substrate (hereinafter, FPC substrate 54) provided at the end of the touch sensor 14 and the touch IC 16. Examples of the electronic components 52 include a driver IC of the display panel 44, a memory, a wireless communication module, a power supply circuit, an electronic element (for example, a coil), and the like.

[0057] Electronic components including processors may sometimes experience a decrease in processing performance or malfunction as the internal temperature or the surrounding temperature rises. In order to suppress this phenomenon, a heat sink or heat conduction path for dissipating the heat generated inside the device may be provided in the electronic device 10. In the example of this figure, a heat sink 56 (conductive component) made of conductive materials such as aluminum (Al) and copper (Cu) is mounted on the host processor 18 and the electronic component 52.

[0058] <Configuration of Heat Sink 56>

[0059] Figure 4 yes Figure 3The enlarged view of the A part of FIG. 5 shows the relative positional relationship between the touch sensor 14 and the heat sink 56. In the following description, the plurality of first electrodes 21 are distinguished by being labeled with identification numbers such as #1, #2, #3, and #4 from the left. In addition, for the convenience of illustration, only the first electrode 21 of the plurality of electrodes 20 constituting the touch sensor 14 is recorded, and the second electrode 22 is omitted.

[0060] Figure 4 The dotted line shown in the top view below corresponds to the outline 60 of the rectangular heat sink 56. If the outermost point in the X direction of the outline 60 is set as the "end point 62", the end point 62 is located on the first electrode 21 of "#2". Hereinafter, the first electrode 21 overlapping the position of the end point 62 is referred to as the "end side electrode 64". In this case, the first electrode 21 of "#1" is located outside the end side electrode 64, while the first electrodes 21 of "#3, #4" are located inside the end side electrode 64.

[0061] Figure 4 The upper graph shows the X coordinate (unit: mm) and the overlap area S (unit: mm). 2 ). The "overlap area S" corresponds to the area of ​​the overlapped portion of each first electrode 21 and the heat sink 56. As can be understood from the coordinate graph, the overlap area S at "#1" becomes the minimum value (=0), and the overlap area at "#3, #4" becomes the maximum value. Here, it should be noted that the overlap area S at "#2" is a value between the maximum value and the minimum value (that is, an intermediate value).

[0062] Figure 5 yes Figure 3 The enlarged view of the B portion of FIG. 6 shows the relative positional relationship between the first electrode 21, the second electrode 22, and the heat sink 56 near the end point 62. For the convenience of illustration, only one first electrode 21 and one second electrode 22 are shown.

[0063] The heat sink 56 is arranged so that the long side is parallel to the X direction and the short side is parallel to the Y direction. In this case, the end point 62 is the outermost point in the X direction and the outermost point in the Y direction in the contour line 60. And, the end point 62 is located at the intersection region 68 where one electrode (that is, the end side electrode 64) of the plurality of first electrodes 21 and one electrode (that is, the end side electrode 66) of the plurality of second electrodes 22 intersect.

[0064] It should be noted that the configuration and shape of the heat sink 56 are not limited to Figure 4 and Figure 5 For example, Fig. 6AAs shown in FIG. 1 , the heat sink 56 may be arranged in a tilted state relative to the sensor area As of the touch sensor 14. Figure 6B As shown, the contour line 60 of the heat sink 56 may include not only straight line components but also curved line components.

[0065] <Functions and Effects of Electronic Device 10>

[0066] The electronic device 10 in the first embodiment is configured as described above. Figure 7 and Figure 8 While explaining.

[0067] Figure 7 is shown with as an example Figure 4 The corresponding comparative example diagram shows the relative positional relationship between the touch sensor 14 and the heat sink 56. Figure 7 As can be understood from the top view below, the end point 62 on the contour line 60 is located between the first electrodes 21 of "#2, #3". Figure 7 As shown in the upper graph, the overlapping area S at "#1, #2" is the minimum value (=0), and the overlapping area S at "#3, #4" is the maximum value. Here, it is noted that the overlapping area S changes sharply in the interval of "#1, #2".

[0068] Figure 8 It is shown by Figure 4 The horizontal axis of the coordinate graph represents the X coordinate (unit: mm), and the vertical axis of the coordinate graph represents the detection value obtained by MCU38 (unit: none). Here, it is assumed that the electronic pen 12 is not in contact with the touch surface of the electronic device 10 ( Figure 2 The protective panel 48) is in contact with the "hovering state".

[0069] As can be understood from the comparative example (the dotted line graph), peaks of the detection values ​​occur at both ends of the heat sink 56. This is considered to be because Figure 7 The overlapping area S shown in FIG. 1 changes sharply in the interval "#2, #3", so a difference occurs in the magnitude of the common mode noise mixed into the signal of the positive electrode and the signal of the negative electrode, and the difference is generated by the differential amplifier 30 ( Figure 1 ) and the difference is magnified.

[0070] On the other hand, as can be understood from the embodiment (solid line graph), the height of the peaks generated at the positions of both ends of the heat sink 56 is greatly suppressed. This is considered to be because: Figure 4The overlapping area S shown takes an intermediate value in the interval “#2”, and the rapid change in the overlapping area S is mitigated compared to the case of the comparative example, so that the difference in the magnitude of the common mode noise described above becomes relatively small.

[0071] In particular, by making the length of the contour line 60 overlapping the end side electrode 64 ( Figure 4 The heat sink 56 is configured so that the distance between the end electrodes 64 and 66 and the end electrodes 64 and 66 is greater than 10 mm (the portion indicated by the thick dotted line on the lower side) and the above-mentioned change mitigation effect appears more significantly. In addition, the end point 62 is preferably located close to the center line of the end side electrodes 64 and 66 (for example, if the width of the end side electrodes 64 and 66 is defined as W, it is within the range of ±W / 4 from the center line).

[0072] It should be noted that, in addition to the above-mentioned heat sink 56 and heat conduction path, the conductive component may also be arranged on the main substrate 42 ( Figure 3 ) may be a variety of electronic components 52 on the main substrate 42, or a module (e.g., a battery pack) independent of the main substrate 42. In particular, considering that the possibility of electromagnetic interference with the touch sensor 14 increases as the contour line 60 becomes longer, the conductive component is preferably a component that occupies a relatively large area, such as the heat sink 56, the heat conduction path, or the battery pack.

[0073] As described above, the electronic device 10 includes: a touch sensor 14, which is configured to include a plurality of electrodes 20 that are separated from each other and arranged in a planar shape along the arrangement direction; a differential amplifier 30 that amplifies and outputs the difference between the positive side signal and the negative side signal selectively output from the plurality of electrodes 20; an MCU 38 (position detection unit) that detects the touch position in the sensor area As formed by the touch sensor 14 based on the output signal from the differential amplifier 30; and a conductive member (here, a heat sink 56), which is a member composed of a conductive material or includes a conductive material, and is arranged in a manner that partially overlaps with the sensor area As in a plan view. In addition, the heat sink 56 is arranged in a manner that the outermost end point 62 in the arrangement direction is located on any one of the plurality of electrodes 20.

[0074] In this way, since the outermost end point 62 in the arrangement direction is configured to be located on any one of the plurality of electrodes 20, the area of ​​the overlapping portion between each first electrode 21 and the heat sink 56, that is, the overlapping area S, which changes sharply along the arrangement direction can be alleviated, and the difference in the magnitude of the common mode noise mixed into the signal of the positive electrode and the signal of the negative electrode can be reduced. Thus, the relationship with the heat sink 56 that may become a source of noise is taken into consideration and the noise cancellation effect of the differential amplification method is further exerted.

[0075] Alternatively, the plurality of electrodes 20 may include a plurality of first electrodes 21 disposed to be separated from each other along the X direction (first direction) and a plurality of second electrodes 22 disposed to be separated from each other along the Y direction (second direction) intersecting the X direction, and the heat sink 56 may be disposed so that the end point 62 is located at an intersection region 68 where any one of the plurality of first electrodes 21 and the plurality of second electrodes 22 (end side electrodes 64, 66) intersect. Thus, the above-mentioned noise canceling effect is simultaneously exerted on both the first electrode 21 and the second electrode 22.

[0076] [Second embodiment]

[0077] Next, regarding the electronic device 100 in the second embodiment, referring to Figure 9 to Figure 16B It should be noted that the same reference numerals may be used to denote the same configuration or function as that of the first embodiment, and description thereof may be omitted.

[0078] <Device Structure of Electronic Device 100>

[0079] Fig. 9 1 is a circuit diagram related to the position detection function of the electronic device 100 in the second embodiment of the present invention. Figure 1 The same is true for the electronic device 10), which may be composed of, for example, a tablet terminal, a smartphone, or a personal computer.

[0080] Specifically, the electronic device 100 includes the same structure as the first embodiment ( Figure 1 The present invention relates to a touch sensor 102 which is different from the touch sensor 14 of the present invention, a touch IC 104 for controlling the touch sensor 102, and a host processor 18 which is electrically connected to the touch IC 104. Here, the touch sensor 102 and the touch IC 104 are equivalent to a position detection device 106 for detecting a touch position of the electronic device 100.

[0081] The touch sensor 102 is overlapped with the display panel 130 ( Fig.10 ) is a sensor of electrostatic capacitance type (specifically, mutual capacitance type or self-capacitance type). The touch sensor 102 is configured to include a plurality of electrodes 110 that are separated from each other and arranged in a planar shape along an arrangement direction. The material of the electrode 110 may also be indium tin oxide (ITO), but is set to be a metal such as copper, silver, or gold in this case.

[0082] The P direction and the Q direction shown in this figure correspond to the P axis and the Q axis of the "sensor coordinate system" defined in the sensor area As formed by the touch sensor 102. In this second embodiment, it is noted that the sensor coordinate system is different from the display panel 130 ( Fig.10 ) is inconsistent with the "display coordinate system" defined in the display area formed.

[0083] The electrode 110 includes a first electrode 111 for detecting a position in the P direction (second direction) and a second electrode 112 for detecting a position in the Q direction (first direction). A plurality of first electrodes 111 are extended in the Q direction and are separated from each other and arranged at equal intervals along a direction orthogonal to the Q direction (that is, the P direction). A plurality of second electrodes 112 are extended in the P direction and are separated from each other and arranged at equal intervals along a direction orthogonal to the P direction (that is, the Q direction).

[0084] The touch IC 104 is configured to include a P selection circuit 114, a Q selection circuit 116, a switch 118, a BP filter 32, a detection circuit 34, an AD converter 36, and an MCU 120. It should be noted that the touch IC 104 may also be provided with a differential amplifier 30 ( Figure 1 ).

[0085] The P selection circuit 114 is a multiplexer connected to the plurality of first electrodes 111. The P selection circuit 114 selects one electrode from the plurality of first electrodes 111 according to the instruction signal from the MCU 120, and sequentially outputs the P signal from the selected electrode. The Q selection circuit 116 is a multiplexer connected to the plurality of second electrodes 112. The Q selection circuit 116 selects one electrode from the plurality of second electrodes 112 according to the instruction signal from the MCU 120, and sequentially outputs the Q signal from the selected electrode.

[0086] The switch 118 is connected to the output sides of the P selection circuit 114 and the Q selection circuit 116. The switch 118 selectively outputs one of the signals in accordance with a command signal from the MCU 120.

[0087] MCU120 is a device capable of processing the digital signal output from the AD converter 36 to detect the touch position in the sensor area As. MCU120 uses the above-mentioned pen detection function or touch detection function to calculate the position of the sensor coordinate system, and transforms the obtained PQ coordinate value into the position (XY coordinate value) of the display coordinate system by performing coordinate transformation. The coordinate transformation is uniquely determined according to the relative position relationship between the touch sensor 102 and the display panel 130. In the case where the sensor coordinate system and the display coordinate system are both orthogonal coordinate systems, the coordinate transformation is a two-dimensional affine transformation of the rotation angle θ [rad] (where 0<θ<π / 2) with a fixed point as the center.

[0088] <Device Structure of Electronic Device 100>

[0089] Fig.10 yes Fig. 9The electronic device 100 is an exploded perspective view of the electronic device 100 shown in FIG. Figure 2 As in the case of the electronic device 10 of the embodiment, the back cover 40, the main substrate 42, the display panel 130, the touch sensor 102 and the front cover 46 are stacked in order from the back side. As in the case of the first embodiment, the touch sensor 102 can be an external sensor or a built-in sensor (on-cell type or in-cell type).

[0090] The display panel 130 is formed of, for example, a liquid crystal panel, an organic EL panel, or electronic paper, etc. The display panel 130 drives a plurality of pixels 134 by applying a driving voltage to matrix signal lines arranged in row and column directions, thereby displaying an image or video in a display area.

[0091] Fig.11 It is shown Fig.10 FIG. 1 is a diagram showing a structure of a driving circuit 132 provided in a display panel 130 of FIG. The driving circuit 132 is configured to include a matrix of signal lines arranged in the row direction and the column direction and a plurality of pixels 134 corresponding to the intersections of the matrix. The matrix of signal lines is composed of a plurality of source signal lines 136 extending in the Y direction and arranged at equal intervals in the X direction and a plurality of gate signal lines 138 extending in the X direction and arranged at equal intervals in the Y direction.

[0092] Each pixel 134 is configured to include a thin film transistor (hereinafter, TFT140) and a pixel electrode 142. A source signal line 136 corresponding to the pixel 134 is connected to the source terminal of the TFT140. A gate signal line 138 corresponding to the pixel 134 is connected to the gate terminal of the TFT140. A pixel electrode 142 corresponding to the pixel 134 is connected to the drain terminal of the TFT140.

[0093] The driving circuit 132 performs display driving of the display panel 130 by applying an AC driving voltage to the matrix-shaped signal lines in a “frame inversion method”. Fig. 12A In the "row line inversion method", the driving circuit 132 applies the driving voltage to the plurality of gate signal lines 138 in an alternating manner so as to reverse the positive and negative directions. Fig. 12B In the "column line inversion method", the driving circuit 132 applies driving voltages to a plurality of source signal lines 136 in an alternating manner so as to invert positive and negative voltages.

[0094] <Structure of Touch Sensor 102>

[0095] Fig.13 yes Fig. 9A partially enlarged view of the first electrode 111 shown. Each first electrode 111 is composed of metal fine wires 152 and 154 of a mesh structure formed by a mesh 150 of the same shape arranged without gaps in the Q direction. The metal fine wires 152 on one side are arranged in a manner extending along the P direction, and the metal fine wires 154 on the other side are arranged in a manner extending in a direction intersecting the P direction (the intersection angle is 2θ). As can be understood from this figure, a rhombus-shaped mesh 150 with one internal angle of 2θ [rad] is formed by being surrounded by two adjacent metal fine wires 152 and 154. It should be noted that the shape of the mesh 150 may be a quadrilateral other than the above-mentioned rhombus, or may be a polygon including a triangle or a hexagon (so-called polygon).

[0096] Although not shown in the figure, each second electrode 112 ( Fig. 9 ) is composed of metal thin wires 152 and 154 of a mesh structure formed by arranging meshes 150 of the same shape without gaps in the P direction. That is, the second electrode 112 has substantially the same shape as the first electrode 111, and is arranged along a direction different from that of the first electrode 111.

[0097] Fig.14 yes Fig. 9 and Fig.10 FIG. 1 is a top view of the touch sensor 102 shown in FIG. The touch sensor 102 includes a frame area Ab and a collection area Aa in addition to the rectangular sensor area As described above.

[0098] The frame region Ab is a frame-shaped region that surrounds the entire periphery of the sensor region As. Lead wires 156 provided at one end of each of the plurality of electrodes 110 are arranged in the frame region Ab. The lead wires 156 are used to connect the touch sensor 102 and the touch IC 104 (in Fig. 9 In the example of FIG. 1 , the signal line electrically connected to the P selection circuit 114 and the Q selection circuit 116 is shown. It should be noted that the portion indicated by the dots in the frame region Ab corresponds to the portion where the lead wire 156 of the first electrode 111 is arranged. On the other hand, the portion indicated by the hatching of the vertical line in the frame region Ab corresponds to the portion where the lead wire 156 of the second electrode 112 is arranged.

[0099] The collection area Aa is connected to the FPC substrate 54 ( Fig.10 ) corresponding to the strip-shaped area. A plurality of lead lines 156 are arranged in a mutually separated and parallel manner in the collection area Aa. In the example of this figure, the collection area Aa is set at the lower left corner of the sensor area As, but it can also be set at other positions (for example, the center of the long side, the center of the short side, etc.) instead.

[0100] <First Effect>

[0101] The electronic device 100 in the second embodiment is configured as described above. Figure 15A to Figure 15B While explaining.

[0102] Fig.15A and Fig. 15B It is shown by Fig.14 FIG. 1 is a diagram of a first effect achieved by the touch sensor 102. Specifically, Fig.15A A "comparative example" is shown. Fig. 15B For the convenience of illustration, the first electrode 21 (111), the second electrode 22 (112), the source signal line 136 and the gate signal line 138 are shown as one each.

[0103] exist Fig.15A In the embodiment, the touch sensor 14 of the first embodiment is assumed to be used, that is, the X direction is consistent with the P direction and the Y direction is consistent with the Q direction. In this case, the first electrode 21 and the source signal line 136 tend to be in a positional relationship that is parallel to each other. Therefore, by generating electromagnetic interference with the source signal line 136, common mode noise is easily mixed into the detection signal of the touch sensor 14. It should be noted that the same tendency as above can also be seen in the relationship between the second electrode 22 and the gate signal line 138.

[0104] exist Fig. 15B In the figure, it is assumed that the touch sensor 102 of the second embodiment is used, that is, the X direction is inconsistent with the P direction and the Y direction is inconsistent with the Q direction. At this time, the first electrode 111 and the source signal line 136 are always in a "twisted position", so it is difficult to cause electromagnetic interference with the source signal line 136, and the mixing of common mode noise with respect to the detection signal of the touch sensor 14 is suppressed. It should be noted that the same tendency as above can also be seen in the relationship between the second electrode 112 and the gate signal line 138.

[0105] As described above, the touch sensor 102 is a sensor used together with the display panel 130. The display panel 130 drives a plurality of pixels 134 by applying a driving voltage to a matrix signal line (source signal line 136, gate signal line 138) arranged in the X direction (row direction) and the Y direction (column direction), and can display an image or video in the display area. The touch sensor 102 is configured to overlap the display area at least partially when viewed from above, and is configured to include a plurality of electrodes 110 arranged in a rectangular shape. In addition, the plurality of electrodes 110 include a plurality of first electrodes 111 extending in the Q direction (first direction) and arranged separately from each other along the orthogonal direction thereof, and a plurality of second electrodes 112 extending in the P direction (second direction) intersecting the Q direction and arranged separately from each other along the orthogonal direction thereof, and at least one of the P direction and the Q direction is inclined relative to both the X direction and the Y direction.

[0106] In this way, since at least one of the Q direction in which the first electrode 111 extends and the P direction in which the second electrode 112 extends is inclined relative to both the X direction and the Y direction, the "twisted position" relationship can always be maintained between the electrode 110 and the matrix-shaped signal line, and the common mode noise caused by electronic interference with the display panel 130 can be suppressed from mixing into the detection signal of the touch sensor 102.

[0107] In particular, in the "row line inversion method" (see Fig. 12A ) When the display panel 130 displays an image or video of each frame, the P direction and the Q direction are preferably inclined relative to the X direction. By changing the sign of the driving voltage relative to the gate signal line 138 periodically over space and time, the generation of common mode noise is further suppressed.

[0108] Similarly, in the “column line inversion method” (see Fig. 12B ) When the display panel 130 displays an image or video of each frame, the P direction and the Q direction are preferably inclined relative to the Y direction. By changing the sign of the driving voltage relative to the source signal line 136 periodically over space and time, the generation of common mode noise is further suppressed.

[0109] <Second Effect>

[0110] According to the touch sensor 102, an effect independent of the above-mentioned common mode noise suppression effect can also be obtained. Fig.16A and Fig. 16B While explaining. Fig.16AA “comparative example” using the touch sensor 14 of the first embodiment is shown, and Fig. 16B An “example” using the touch sensor 102 of the second embodiment is shown.

[0111] For example, it is assumed that the collection area Aa is set at the lower left corner of the sensor area As and the wiring layout is designed at the second electrode 22, 112 closest to the upper long side. Fig.16A In the "Comparative Example" of , the wiring is routed through the upper right corner, upper left corner, and lower left corner of the sensor area As, so the wiring length L1 at a specific electrode 20 becomes relatively long, and the resistance becomes correspondingly large. Fig. 16B In the "embodiment" of , the wiring is arranged through the upper right corner, lower center, and lower left corner of the sensor area As, so that the wiring length L2 at a specific electrode 110 becomes relatively short and the resistance becomes correspondingly small.

[0112] In this way, when the touch sensor 102 and the MCU 120 are connected by a plurality of lead wires 156, the lead wires 156 may be provided at the end of the electrode 110 that straddles two adjacent sides (that is, the long side and the short side) of the sensor area As, which is close to the MCU 120. Thus, the wiring length at a specific electrode 110 is easily shortened compared to the case where the wiring is provided along the periphery of the sensor area As.

[0113] In addition, in the touch sensor 102, in addition to the electrodes 110 spanning two adjacent sides, there may also be electrodes 110 spanning two opposite sides (that is, long sides or short sides). Accordingly, the options for which side to set the lead wire 156 increase. Thus, the touch sensor 14 ( Figure 1 ) compared to the lead wire 156, there is another effect that the degree of freedom in design related to the configuration of the lead wire 156 is increased.

[0114] [Description of symbols]

[0115] 10, 100‥Electronic device, 12‥Electronic pen, 14, 102‥Touch sensor, 16‥Touch IC, 20, 110‥Electrode, 21, 111‥First electrode, 22, 112‥Second electrode, 30‥Differential amplifier, 38‥MCU (position detection unit), 44, 130‥Display panel, 56‥Heat sink (conductive component), 60‥Contour line, 62‥end point, 64, 66‥end side electrode, 68‥intersection area, 104‥touch IC (position detection unit), 106‥position detection device, 134‥pixel, 136‥source signal line, 138‥gate signal line, 150‥net, 152, 154‥metal fine wire, 156‥lead line, Aa‥collection area, Ab‥frame area, As‥sensor area

Claims

1. An electronic device, characterized in that: have: The touch sensor is configured to include a plurality of electrodes that are separated from each other and arranged in a planar shape along an arrangement direction; A differential amplifier amplifies and outputs a difference between a positive side signal and a negative side signal selectively output from the plurality of electrodes; a position detection unit that detects a touch position within a sensor area formed by the touch sensor based on an output signal from the differential amplifier; and The conductive member is a member made of a conductive material or containing a conductive material, and is arranged so as to partially overlap with the sensor area in a plan view. The conductive member is arranged so that the outermost end point in the arrangement direction is located on any one of the plurality of electrodes. The conductive component is a heat sink, a heat conduction path or a battery pack.

2. The electronic device according to claim 1, characterized in that: The plurality of electrodes comprises: A plurality of first electrodes are arranged separately from each other along a first direction; and A plurality of second electrodes are arranged to be separated from each other along a second direction intersecting the first direction, The conductive component is arranged so that the end point is located at an intersection region where the plurality of first electrodes and any one of the plurality of second electrodes intersect. The first direction is orthogonal to the second direction.

3. The electronic device according to claim 1, characterized in that: When an electrode overlapping the end point in a plan view is defined as an end side electrode, The conductive member is arranged so that the length of the outline overlapping with the end-side electrode becomes 10 mm or more.

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