JP2017091018A - Touch panel and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch panel which can detect a touch accurately, and a display device.SOLUTION: A touch panel includes a plurality of first electrodes extended in a first direction, a plurality of second electrodes extended in a second direction, and insulating films arranged between the first electrodes and the second electrodes. Each of the first and second electrodes is formed of a plurality of mesh-like conductive wires. In each of the first and second electrodes, mesh density of a non-intersection area, where the first and second electrodes do not intersect with each other in plan view, is larger than the mesh density of an intersection area where the first and second electrodes intersect with each other in plan view.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a touch panel and a display device, and more particularly to a capacitive touch panel.

  Conventionally, a display device combining a display panel and a touch panel has been proposed. For example, a capacitive touch panel detects the position of a contact object from a change in capacitance between the contact object and a sensor electrode. Further, as a capacitive sensor electrode, a mesh sensor electrode composed of a linear pattern of a conductor having a low electrical resistance such as copper has been proposed (Patent Document 1).

JP 2014-186687 A

  Although the sensor electrode can be reduced in electrical resistance by the mesh-shaped sensor electrode described in Patent Document 1, the electrical resistance of the sensor electrode is further lowered and touch detection accuracy is improved with the recent increase in screen size of display devices. It is requested to do.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a touch panel and a display device capable of performing touch detection with high accuracy.

  In order to solve the above problems, a touch panel according to the present invention includes a plurality of first electrodes extending in a first direction, a plurality of second electrodes extending in a second direction, and the plurality of first electrodes. An insulating film disposed between the plurality of second electrodes, wherein each of the first electrodes and each of the second electrodes includes a plurality of mesh-shaped conductive lines, and each of the first electrodes and In each second electrode, the mesh density of a non-intersecting region where the plurality of first electrodes and the plurality of second electrodes do not intersect in plan view is such that the plurality of first electrodes and the plurality of second electrodes are flat. It is characterized by being larger than the mesh density of the intersecting region that intersects visually.

  In the touch panel according to the present invention, in each of the first electrodes and each of the second electrodes, the mesh density of the non-intersecting region may be twice the mesh density of the intersecting region.

  In the touch panel according to the present invention, a dummy electrode that is not electrically connected to either the first electrode or the second electrode may be formed in a region where the first electrode and the second electrode are not formed in plan view.

  In the touch panel according to the present invention, when the touch panel is viewed in plan, the intervals between the plurality of mesh-like conductive lines configured by the plurality of first electrodes and the plurality of second electrodes are the intersections. The area may be equal to the non-intersection area.

  In the touch panel according to the present invention, when the touch panel is viewed in plan, the plurality of conductive lines constituting the first electrode and the plurality of conductive lines constituting the second electrode in the intersecting region are mutually It may be arranged so as to be shifted by half the interval between the conductive lines.

  A display device according to the present invention includes the touch panel described above and a display panel that displays an image.

  According to the present invention, it is possible to improve the accuracy of touch detection in a capacitive touch panel.

It is a figure showing the whole touch panel device composition which has a touch panel concerning this embodiment. FIG. 2 is a plan view showing the configuration of the first electrode according to the present embodiment. It is a top view which shows the structure of the 2nd electrode which concerns on this embodiment. It is a top view showing the state where the 1st electrode and the 2nd electrode concerning this embodiment were piled up. It is the schematic which expanded a part of FIG. It is AA 'sectional drawing of FIG. It is a figure which shows an example of the mesh shape of the conductive wire which comprises a 1st electrode. It is a figure which shows an example of the mesh shape of the conductive wire which comprises a 2nd electrode. It is a figure which shows an example of the mesh shape of the conductive wire which comprises the 1st electrode and 2nd electrode at the time of seeing a touch panel planarly. It is a figure which shows the cross | intersection area | region at the time of seeing a touch panel planarly. It is a top view which shows the 1st electrode periphery in the state by which the dummy electrode is arrange | positioned. It is a figure which shows the whole structure of the display apparatus which has a touchscreen which concerns on this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, about drawing, the same code | symbol is attached | subjected to the same or equivalent element, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a diagram showing an overall configuration of a touch panel device 100 having a touch panel 101 according to the present embodiment. As illustrated in FIG. 1, the touch panel device 100 includes, for example, a touch panel 101, a drive signal generation unit 102, and a detection processing unit 103. Note that the drive signal generation unit 102 and the detection processing unit 103 may be configured by a single controller.

  The touch panel 101 includes a plurality of first electrodes XP (XP1 to XPn) extending in the row direction (first direction) and second electrodes YP (YP1 to YPm) extending in the column direction (second direction). Including. An insulating film or the like is formed between the first electrode XP and the second electrode YP, and the first electrode XP and the second electrode YP are arranged so as to intersect each other when seen in a plan view. Here, n and m are integers of 1 or more.

  In the following description, when a common configuration in the first electrodes XP to XPn is described, it is simply expressed as the first electrode XP. Similarly, when a common configuration in the second electrodes YP to YPm is described, it is simply expressed as the second electrode YP.

  The drive signal generator 102 sequentially outputs drive signals (pulse signals) for driving the electrodes to the plurality of first electrodes XP. Specifically, the drive signal generation unit 102 sequentially outputs a pulse signal from the first electrode XP1 to the first electrode XPn, for example.

  The detection processing unit 103 detects the presence / absence of the touch on the touch panel 101 and the touched position based on the change in capacitance between the first electrode XP and the second electrode YP based on the presence / absence of the touch. Specifically, a capacitance (interelectrode capacitance) is generated between the first electrode XP and the second electrode YP based on the pulse signal input to the first electrode XP. Fluctuates depending on the presence or absence of touch. For example, when a contact object such as a finger is touched on the touch panel 101, an electrostatic capacity (touch capacity) is generated between the contact object and each electrode, so that the inter-electrode capacity is reduced according to the touch capacity. Therefore, the presence / absence of a touch on the touch panel 101 and the touched position are detected by detecting a change in interelectrode capacitance.

  Here, an example of the configuration of the first electrode XP and the second electrode YP according to the present embodiment will be described. FIG. 2 is a plan view showing the configuration of the first electrode XP according to the present embodiment. FIG. 3 is a plan view showing the configuration of the second electrode YP according to the present embodiment. FIG. 4 is a plan view showing a state in which the first electrode XP and the second electrode YP according to the present embodiment are overlaid. FIG. 5 is an enlarged schematic view of a part of FIG. 6 is a cross-sectional view taken along the line AA ′ of FIG.

  In FIG. 1, the first electrode XP and the second electrode YP are shown as straight lines for convenience, but as shown in FIG. 2, the first electrode XP extends in the row direction and the width in the column direction periodically. The shape may change. Similarly, as shown in FIG. 3, the second electrode YP may have a shape that extends in the column direction and whose width in the row direction changes periodically. Specifically, as shown in FIG. 2, the first electrode XP has a rhombus-shaped wide width portion (first electrode portion 111) and a short width portion (first width) in the row direction. The wiring portions 112) are alternately arranged. Similarly, as shown in FIG. 3, the second electrode YP has a rhombic shape in the column direction and a wide wide part (second electrode part 121) and a short short part (second wiring part). 122) are alternately arranged. Further, as shown in FIG. 5, the first electrode portion 111 and the second electrode portion 121 are arranged without overlapping when seen in a plan view, and a part of the first wiring portion 112 and one of the second wiring portions 122 are arranged. The parts are arranged so as to intersect with each other when seen in a plan view. Note that the entire first wiring portion 112 and the entire second wiring portion 122 may be arranged so as to intersect each other when seen in a plan view. Here, in the first electrode XP and the second electrode YP, a region where the first electrode XP and the second electrode YP intersect (in FIG. 5, a part of the first wiring part 112 and a part of the second wiring part 122 are The intersecting region is defined as the intersecting region 130. In the first electrode XP and the second electrode YP, a region where the first electrode XP and the second electrode YP do not intersect is defined as a non-intersecting region 131. A region where neither the first electrode XP nor the second electrode YP is formed is referred to as an electrode non-forming region 140.

  As shown in FIG. 6, the first electrode XP is formed on one surface of the insulating film 200, and the second electrode YP is formed on the other surface of the insulating film 200. A lower insulating layer 201 is formed below the first electrode XP so as to cover the first electrode XP. An upper insulating layer 202 is formed above the second electrode YP so as to cover the second electrode YP. As described above, the first electrode XP and the second electrode YP are formed apart from each other with the insulating film 200 interposed therebetween. The arrangement position of the first electrode XP and the arrangement position of the second electrode YP may be reversed.

  The first electrode XP and the second electrode YP according to the present embodiment are formed in a mesh shape by a plurality of conductive lines made of a conductive material having a high conductivity such as copper or silver. The mesh shape of the conductive lines constituting the first electrode XP and the second electrode YP will be described with reference to FIGS. FIG. 7 is a diagram illustrating an example of the mesh shape of the conductive lines constituting the first electrode XP. FIG. 8 is a diagram illustrating an example of the mesh shape of the conductive lines constituting the second electrode YP.

  As shown in FIG. 7, the first electrode XP includes a plurality of mesh-shaped first conductive lines 113 extending in directions intersecting each other so as to have a plurality of intersections. For example, the plurality of first conductive lines 113 form a mesh shape including a plurality of quadrangles in which one of the two diagonal lines is DV and the other is DH. In the present embodiment, the ratio (mesh density) of the first conductive lines 113 to the total area of the non-intersecting regions 131 in the first electrode XP is the ratio of the first conductive lines 113 to the total area of the intersecting regions 130 in the first electrode XP. It becomes larger than the ratio (mesh density). Specifically, the mesh density of the non-intersecting region 131 in the first electrode XP is twice the mesh density of the intersecting region 130 in the first electrode XP. In FIG. 7, the interval between the plurality of first conductive lines 113 in the intersecting region 130 is set to be twice the interval between the plurality of first conductive lines 113 in the non-intersecting region 131.

  As shown in FIG. 8, the second electrode YP includes a plurality of mesh-like second conductive lines 123 extending in directions intersecting with each other so as to have a plurality of intersections. Similar to the first electrode XP, the plurality of second conductive lines 123 form a mesh shape composed of a plurality of quadrangles in which one of the two diagonal lines is DV and the other is DH. In the present embodiment, the ratio (mesh density) of the second conductive lines 123 to the total area of the non-intersecting regions 131 in the second electrode YP is the ratio of the second conductive lines 123 to the total area of the intersecting regions 130 in the second electrode YP. It becomes larger than the ratio (mesh density). Specifically, the mesh density of the non-intersecting region 131 in the second electrode YP is twice the mesh density of the intersecting region 130 in the second electrode YP. In FIG. 8, the intervals between the plurality of second conductive lines 123 in the intersecting region 130 are twice the intervals between the plurality of second conductive lines 123 in the non-intersecting region 131. Note that the first electrode XP and the second electrode YP have the same mesh shape, and the mesh density of the first electrode XP and the mesh density of the second electrode YP in the non-intersecting region 131 are equal. Further, the mesh density of the first electrode XP and the mesh density of the second electrode YP in the intersection region 130 are equal.

  As described above, when the mesh density of the non-crossing region 131 in the first electrode XP is twice the mesh density of the crossing region 130 in the first electrode XP, the electrical resistance value of the non-crossing region 131 of the first electrode XP is It becomes 1/2 of the electric resistance value of the crossing region 130 of the one electrode XP. Similarly, when the mesh density of the non-intersecting region 131 in the second electrode YP is twice the mesh density of the intersecting region 130 in the second electrode YP, the electrical resistance value of the non-intersecting region 131 of the second electrode YP is the second value. The electric resistance value of the electrode crossing region 130 is ½. Therefore, according to the present embodiment, the electrical resistance value of the first electrode XP and the electrical resistance value of the second electrode YP are smaller than in the case where the mesh density is equal in the intersecting region 130 and the non-intersecting region 131. And, as the electrical resistance value of the first electrode XP and the electrical resistance value of the second electrode YP are smaller, each electrode can transmit a high-frequency signal. For example, the drive signal generator 102 outputs the first electrode XP to the first electrode XP. The frequency of the pulse signal to be performed can be set high, and the accuracy of touch detection is improved. In addition, according to the present embodiment, even a high-frequency signal output from an active pen or the like can be transmitted satisfactorily, so that when sensitive touch detection such as an active pen is required. Can also be applied.

  In addition, according to the present embodiment, since the mesh density of the non-intersecting region 131 in the first electrode XP and the second electrode YP is increased, the touch capacitance generated when a touch object such as a finger is touched on the touch panel 101 is increased. . Therefore, the change in the interelectrode capacitance when the contact object is touched on the touch panel 101 is increased, and the accuracy of touch detection is improved.

  When the touch panel 101 in which the first electrode XP having the mesh shape shown in FIG. 7 and the second electrode YP having the mesh shape shown in FIG. As shown, the mesh density of the intersecting region 130 and the mesh density of the non-intersecting region 131 are equal. FIG. 9 is a diagram illustrating an example of the mesh shape of the conductive lines constituting the first electrode XP and the second electrode YP when the touch panel 101 is viewed in plan. As shown in FIG. 9, when the touch panel 101 is viewed in plan, the intervals between the plurality of first conductive lines 113 constituting the first electrode XP and the plurality of second conductive lines 123 constituting the second electrode YP. However, the intersection region 130 and the non-intersection region 131 are equal.

  FIG. 10 is a diagram illustrating an intersection region 130 when the touch panel 101 is viewed in a plan view. In FIG. 10, the first conductive line 113 is indicated by a solid line, and the second conductive line 123 is indicated by a dotted line. As shown in FIG. 10, in the present embodiment, in the intersecting region 130 of the first electrode XP and the second electrode YP that intersect each other, the plurality of first conductive lines 113 and the plurality of second conductive lines 123 are mutually conductive lines. It is arranged so as to be shifted by half of the interval. Therefore, when the touch panel 101 is viewed in plan with the first electrode XP and the second electrode YP being overlapped, the plurality of first conductive lines 113 and the plurality of second conductive lines 123 are electrically conductive in the intersection region 130. They will be staggered so as to be offset by half the line spacing. Further, the first conductive line 113 or the second conductive line 123 in the non-intersecting region 131 is arranged on the extension of the first conductive line 113 in the intersecting region 130. Similarly, the first conductive line 113 or the second conductive line 123 in the non-intersecting region 131 is disposed on the extension of the second conductive line 123 in the intersecting region 130. In this way, the intervals between the plurality of first conductive lines 113 and the plurality of second conductive lines 123 in the intersecting region 130 are the same as the intervals between the plurality of first conductive lines 113 in the non-intersecting region 131 and the non-intersecting regions 131, respectively. It becomes equal to each space | interval of the some 2nd conductive wire 123 in. Then, when the touch panel 101 is viewed in plan with the first electrode XP and the second electrode YP being overlapped, a plurality of first conductive lines 113 and a plurality of second conductive lines as shown in FIG. 123, the mesh shape is configured so that the mesh density is uniform in the entire touch panel 101.

  Further, it is preferable that the separation distance between the first electrode XP and the second electrode YP in the stacking direction is small. In the present embodiment, in the first electrode XP and the second electrode YP, the mesh density of the intersecting region 130 is set to ½ of the mesh density of the non-intersecting region 131. In the intersecting region 130, the plurality of first conductive lines 113 and the plurality of second conductive lines 123 are arranged so as to be shifted by a half of the interval between the conductive lines. Therefore, if the separation distance between the first electrode XP and the second electrode YP is large, the plurality of first conductive lines 113 and the plurality of second conductive lines 123 overlap each other in the intersection region 130 when the touch panel 101 is viewed obliquely. In some cases, there is a difference in mesh density between the intersecting region 130 and the non-intersecting region 131. Due to the difference in mesh density between the intersecting region 130 and the non-intersecting region 131, streaky unevenness due to the conductive wire is easily observed. Such a problem can be avoided by reducing the distance between the first electrode XP and the second electrode YP. For example, by making the separation distance between the first electrode XP and the second electrode YP sufficiently smaller than the dimensions (DV, DH) of the mesh, even when the touch panel 101 is viewed from an oblique direction, a plurality of first It appears that the first conductive lines 113 and the plurality of second conductive lines 123 are arranged alternately without overlapping. As a result, when the touch panel 101 is viewed from an oblique direction, streaky irregularities due to the conductive wires are less likely to be visually observed.

  Further, when the touch panel 101 is viewed in a plan view, there is an electrode non-formation region 140 in which neither the first electrode XP nor the second electrode YP is formed. When the electrode non-formation region 140 exists, a difference occurs in the mesh density between the region where the electrode is disposed (the first electrode XP and the second electrode YP) and the electrode non-formation region 140, and streaky unevenness due to the conductive wire is visually observed. It becomes easy to be done. In order to avoid such a problem, a dummy electrode DP (shown in FIG. 11) may be formed in the electrode non-formation region 140 where neither the first electrode XP nor the second electrode YP is formed. The dummy electrode DP may be formed on at least one of the one surface and the other surface of the insulating film 200 so as not to be electrically connected to either the first electrode XP or the second electrode YP. FIG. 11 is a plan view showing the periphery of the first electrode XP in a state where the dummy electrode DP is formed. As shown in FIG. 11, the dummy electrode DP is formed in the electrode non-forming region 140 so as not to be electrically connected to the first electrode XP. Specifically, the dummy electrode DP is formed so that a gap is formed between the first electrode XP and the dummy electrode DP when seen in a plan view. Although not shown, the dummy electrode DP is formed so that a gap is formed between the second electrode XP and the dummy electrode DP as in FIG. In order to make the mesh density uniform throughout the touch panel 101, the dummy electrode DP may be formed in a shape similar to the mesh shape of the non-intersecting region 131 of the first electrode XP and the second electrode YP. As a result, the mesh density can be made uniform between the region where the electrode is disposed and the non-electrode-forming region 140, and streaky unevenness due to the conductive wire is less visible. The dummy electrode DP may be formed in a layer different from the first electrode XP and the second electrode YP in the upper insulating layer 202 or the lower insulating layer 201.

  Further, by applying the touch panel 101 according to the present invention to a display device such as a liquid crystal display device or an organic EL display device, a display device having a touch detection function can be realized. FIG. 12 is a diagram showing an overall configuration of the display device 10 having the touch panel 101 according to the present embodiment. As illustrated in FIG. 12, the display device 10 includes a touch panel 101, a drive signal generation unit 102, a detection processing unit 103, a display panel 300 that displays an image, a display drive circuit 301 that drives the display panel 300, A backlight device (not shown) is included. Since the touch panel 101, the drive signal generation unit 102, and the detection processing unit 103 are the same as those shown in FIG. 1, the description thereof is omitted here. The display panel 300 includes a counter substrate (not shown), a TFT substrate (not shown), and a liquid crystal layer (not shown) sandwiched between the two substrates, and is disposed so as to overlap the touch panel 101. The The display drive circuit 301 includes, for example, a gate line drive circuit (not shown) and a data line drive circuit (not shown). The touch panel 101 may be a so-called external touch panel attached to the display surface of the display panel 300 or a so-called on-cell touch panel in which the touch panel 101 is provided between the glass substrate of the display panel 300 and the polarizing plate. Good.

  In the above description, the mesh density of the non-intersecting region 131 in the first electrode XP is twice the mesh density of the intersecting region 130 in the first electrode XP, and the mesh density of the non-intersecting region 131 in the second electrode YP is The mesh density of the intersecting region 130 in the second electrode YP is twice, but the present invention is not limited to this example. The mesh density of the non-intersecting region 131 of each electrode can be configured as k (k> 1) times the mesh density of the intersecting region 130 of each electrode.

  A known technique can be applied as a method of forming the first electrode XP, the second electrode YP, and the dummy electrode DP according to the present embodiment. For example, etching using a photolithography of a metal thin film, printing resist, etc. It can be formed by a method such as etching, printing of a conductive resin material, lift-off, or the like.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and those skilled in the art have appropriately changed the above embodiments without departing from the spirit of the present invention. It goes without saying that the form is also included in the technical scope of the present invention.

  DESCRIPTION OF SYMBOLS 10 Display apparatus, 100 Touch panel apparatus, 101 Touch panel, 102 Drive signal generation part, 103 Detection processing part, 111 1st electrode part, 112 1st wiring part, 113 1st conductive wire, 121 2nd electrode part, 122 2nd wiring Part, 123 second conductive line, 130 crossing region, 131 non-crossing region, 140 electrode non-forming region, 200 insulating film, 201 lower insulating layer, 202 upper insulating layer, 300 display panel, 301 display driving circuit, DP dummy electrode , XP first electrode, YP second electrode.

Claims (6)

A plurality of first electrodes extending in a first direction;
A plurality of second electrodes extending in a second direction;
An insulating film disposed between the plurality of first electrodes and the plurality of second electrodes;
Including
Each of the first electrodes and the second electrodes is composed of a plurality of mesh-like conductive wires,
In each of the first electrodes and the second electrodes, the mesh density of a non-intersecting region where the plurality of first electrodes and the plurality of second electrodes do not intersect in plan view is the plurality of first electrodes and the plurality of second electrodes. Greater than the mesh density of the intersecting region where the second electrode of
A touch panel characterized by that. In each of the first electrodes and the second electrodes, the mesh density of the non-intersecting region is twice the mesh density of the intersecting region.
The touch panel according to claim 1. In a region where the first electrode and the second electrode are not formed in a plan view, a dummy electrode that is not electrically connected to either the first electrode or the second electrode is formed.
The touch panel according to claim 1. When the touch panel is viewed in plan, the intervals between the plurality of mesh-like conductive lines formed by the plurality of first electrodes and the plurality of second electrodes are the crossing region and the non-crossing region. Is equal to
The touch panel according to claim 1. When the touch panel is viewed in plan, the plurality of conductive lines constituting the first electrode and the plurality of conductive lines constituting the second electrode in the intersecting region are only half the distance between the conductive lines. Are displaced,
The touch panel according to claim 1. The touch panel according to claim 1 and a display panel for displaying an image.
A display device characterized by that.

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