JP6265021B2 - Touch panel sensor, touch panel device, and display device - Google Patents

Description

  The present invention relates to a touch panel sensor having electrodes, a touch panel device including a touch panel sensor, a display device including a touch panel sensor, and a method for manufacturing the touch panel sensor.

  Today, touch panel devices are widely used as input means. In many cases, the touch panel device is used as an input means for various devices including an image display mechanism such as a liquid crystal display or a plasma display (for example, a ticket vending machine, an ATM device, a mobile phone, a game machine) and the image display mechanism. It is used. In such a device, the touch panel sensor is disposed on the display surface of the image display mechanism, and thus the touch panel device enables a very direct input to the display device. An area of the touch panel sensor that faces the display area of the image display mechanism is transparent, and this area of the touch panel sensor constitutes an active area that can detect a contact position (approach position).

  The touch panel device can be classified into various types based on the principle of detecting a contact position (approach position) on the touch panel sensor. In recent years, a projected capacitive coupling type touch panel device has been widely used due to various advantages. The projected capacitive touch panel device includes a pair of detection electrode groups arranged in an active area. For example, in the touch panel sensor disclosed in Patent Document 1, the detection electrode located in the active area is formed of a conductive wire made of a metal material. In this touch panel sensor, since the electrical conductivity of the metal material is high, the surface resistivity (unit: Ω / □) can be sufficiently reduced. On the other hand, a metal material excellent in conductivity is opaque. Therefore, each detection electrode is configured as a conductor mesh in which metal conductors are arranged in a mesh pattern that defines a large number of opening areas, and ensures the visible light transparency of the touch panel sensor in the active area. . However, such a conductor mesh is known to cause problems such as moire and shading unevenness. Various studies have been conducted to eliminate such problems.

Patent No. 5224203

  Moire is a phenomenon in which light and dark streaks become visible. Regularity (periodicity) of the mesh pattern of the conductor mesh and regularity of the pattern of other members overlaid on the conductor mesh (for example, This is caused by interference with the regularity of the pixel arrangement of the image display mechanism. For this reason, it has been generally considered that making the mesh pattern of the conductor mesh irregular is effective for making moiré invisible.

  On the other hand, shading unevenness is a phenomenon in which the amount of light transmitted through the conductor mesh and the amount of external light reflected from the conductor mesh are not uniform in the surface, and a brightly observed portion is locally present. The occurrence of shading unevenness is considered to be caused by local non-uniformity of the mesh pattern of the conductor mesh.

  That is, making the mesh pattern of the conductor mesh irregular is effective for making the moire invisible, and making the mesh pattern of the conductor mesh effective for making the shading unevenness invisible. For this reason, in the prior art, there is no conductor mesh that can cope with both moire and shading unevenness. The present invention has been made in view of the above points, and an object of the present invention is to provide a touch panel sensor having detection electrodes formed in a mesh pattern that makes both moire and shading unevenness inconspicuous. Another object of the present invention is to provide a touch panel device and a display device including the touch panel sensor.

The touch panel sensor according to the present invention includes:
Comprising a detection electrode for forming a mesh pattern defining a plurality of opening regions;
In the integrated value distribution at each angle of the power spectrum of the mesh pattern obtained by applying Fourier transform and polar coordinate transformation to the scan data of the mesh pattern created by using a planar scanner, it is 0 ° or more and less than 180 °. The standard deviation σ _p1 of the power spectrum integrated value within the range of 60 ° (θ _p1 ± 30 [°]) centered on the first peak angle θ _p1 [°] at which the power spectrum integrated value becomes the largest within the range, and ,
In the power spectrum integrated value distribution of the mesh pattern, within the range of 60 ° centered on the second peak angle θ _p2 [°] at which the power spectrum integrated value becomes the second largest within the range of 0 ° to less than 180 °. The standard deviation σ _p2 of the power spectrum integrated value at (θ _p2 ± 30 [°]),
The first peak angle θ _p1 [°] and second peak angle θ _p2 [°] in the integrated value distribution of the power spectrum of the mesh pattern, and the mesh pattern at the first peak angle θ _p1 [°]. A first spatial frequency forming a first peak located on a higher frequency side than a fundamental frequency in the distribution of power spectrum at each spatial frequency, and the mesh pattern at the second peak angle θ _p2 [°]. The image data of the regular pattern determined based on the second spatial frequency forming the first peak located on the higher frequency side than the fundamental frequency in the distribution of the power spectrum at each spatial frequency, Fourier transform and In the integrated value distribution at each angle of the power spectrum of the regular pattern obtained by performing polar coordinate transformation The first peak angle theta _p1 standard deviation of the power spectrum integral value in [°] in the range of 60 ° around the (theta _p1 ± 30 [°]) sigma _ap1, and the second peak angle theta _p2 The standard deviation σ _ap2 of the power spectrum integrated value within a range of 60 ° centered on [°] (θ _p2 ± 30 [°]) satisfies the following condition,
1.02 ≦ σ _p1 / σ _ap1 ≦ 1.16
1.02 ≦ σ _p2 / σ _ap2 ≦ 1.16
The regular pattern has a coordinate system set in the same manner as when the power spectrum of the mesh pattern is specified from the scan data of the mesh pattern, and the first space has a first peak angle θ _p1 [°]. The first straight line groups arranged at a constant pitch having a length corresponding to the frequency, and arranged at a constant pitch having a length corresponding to the second spatial frequency in the direction of the second peak angle θ _p2 [°]. And a second straight line group.

  In the touch panel sensor according to the present invention, in the integrated value distribution of the power spectrum of the mesh pattern, only two local maximum values of the power spectrum integrated value may exist within a range of 0 ° to less than 180 °.

In the touch panel sensor according to the present invention,
60 ° ≦ | θ _p1 −θ _p2 | ≦ 80 °, or 100 ° ≦ | θ _p1 −θ _p2 | ≦ 120 °
You may make it be.

  In the touch panel sensor according to the present invention, the opening regions may be arranged in two intersecting directions.

  In the touch panel sensor according to the present invention, the opening area may have a quadrangular shape.

In the touch panel sensor according to the present invention,
The mesh pattern includes conductive connecting elements extending between two branch points to define the open area;
Each branch point of the mesh pattern is formed on a plurality of line segments extending between two intersections to define an opening region, and is on one intersection of a reference pattern in which the opening regions are regularly arranged or a predetermined length. Less than or equal to the length of the one intersection point, and each connecting element of the mesh pattern has two intersection points respectively corresponding to two intersection points located at both ends of one line segment. You may extend between the branch points.

  In the touch panel sensor according to the present invention, the reference pattern may be regularly arranged in two directions in which opening regions having a certain shape intersect.

  In the touch panel sensor according to the present invention, the reference pattern may be regularly arranged in two directions in which certain rectangular opening areas intersect.

  In the touch panel sensor according to the present invention, the scan data of the mesh pattern may include the mesh as a two-dimensional image of a region in which a line width of a conductive wire forming the mesh pattern is configured by a plurality of pixels and is 3 cm × 3 cm or more The pattern may be converted into image data.

  In the touch panel sensor according to the present invention, the scan data may be binarized before being subjected to Fourier transform.

  In the touch panel sensor according to the present invention, the binarized scan data may be subjected to a thinning process before being subjected to Fourier transform.

  In the touch panel sensor according to the present invention, the standard deviation related to the integrated value distribution of the power spectrum of the mesh pattern is subjected to a blurring process within an angular range of ± 10 ° using a Gaussian filter. The specified value may be used later.

  In the touch panel sensor according to the present invention, the standard deviation related to the integrated value distribution of the power spectrum of the regular pattern is subjected to a blurring process within ± 10 ° angle range using a Gaussian filter. The specified value may be used later.

In the touch panel sensor according to the present invention,
The detection electrode includes a first detection electrode and a second detection electrode arranged to overlap the first detection electrode;
The mesh pattern may be formed by the first detection electrode.

In the touch panel sensor according to the present invention,
The detection electrode includes a first detection electrode and a second detection electrode arranged to overlap the first detection electrode;
A part of the mesh pattern may be formed by the first detection electrode, and another part of the mesh pattern may be formed by the second detection electrode.

  The touch panel device according to the present invention includes any of the touch panel sensors according to the present invention described above.

A display device according to the present invention comprises:
Any of the touch panel sensors according to the invention described above;
An image display mechanism disposed to overlap the touch panel sensor.

  According to the present invention, both moire and shading unevenness can be made inconspicuous.

FIG. 1 is a diagram for explaining an embodiment of the present invention, and schematically shows a display device and a touch panel device. FIG. 2 is a plan view showing a touch panel sensor of the touch panel device. FIG. 3 is a diagram illustrating an example of a layer configuration of the touch panel sensor. FIG. 4 is a diagram illustrating another example of the layer configuration of the touch panel sensor. FIG. 5 is a plan view showing a mesh pattern of a conductor mesh constituting a first detection electrode included in the first electrode of the touch panel sensor. FIG. 6 is a plan view showing a mesh pattern of a conductor mesh that forms a second detection electrode included in the second electrode of the touch panel sensor. FIG. 7 is a plan view showing a mesh pattern formed in a state where the conductor mesh of the first detection electrode and the conductor mesh of the second detection electrode are overlapped. FIG. 8 is a diagram for explaining a method for determining the mesh pattern of the conductor mesh, and is a plan view showing the mesh pattern of the conductor mesh together with the reference pattern. FIG. 9 is a diagram for explaining a method for determining a mesh pattern of a conductor mesh, and shows a mesh pattern of a conductor mesh that forms a first detection electrode and a mesh pattern of a conductor mesh that forms a second detection electrode. It is a top view shown in the piled-up state with the reference pattern regarding each mesh pattern. FIG. 10 is an enlarged view showing a part of mesh pattern scan data. FIG. 11 is an enlarged view showing a part of the scan data of FIG. 10 that has been binarized. FIG. 12 is a diagram showing scan data before and after the thinning process. FIG. 13 is a diagram illustrating a Fourier transform power spectrum image of a mesh pattern. FIG. 14 is a diagram showing the polar transform of the Fourier transform power spectrum image of FIG. FIG. 15 is a graph showing the integrated value distribution at each angle of the power spectrum of the mesh pattern. FIG. 16 is a graph showing the distribution of the power spectrum of the mesh pattern at each spatial frequency. FIG. 17 is a plan view showing a regular pattern identified based on a power spectrum conversion image of a mesh pattern. FIG. 18 is a graph showing the integrated value distribution at each angle of the power spectrum for a plurality of patterns. FIG. 19 is a plan view showing a typical example of the pixel array of the image display mechanism. FIG. 20 is a diagram corresponding to FIG. 2 and illustrating a modified example of the electrodes of the touch panel sensor.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, the vertical / horizontal dimension ratio, and the like are appropriately changed and exaggerated from those of the actual ones.

  In the present specification, the terms “plate (substrate)”, “sheet”, and “film” are not distinguished from each other based only on the difference in names. For example, the “plate” is a concept including a member that can be called a sheet or a film, and cannot be distinguished only by a difference in names.

  Furthermore, as used in this specification, the shape and geometric conditions and the degree thereof are specified. For example, terms such as “parallel”, “orthogonal”, “identical”, length and angle values, etc. Without being bound by meaning, it should be interpreted including the extent to which similar functions can be expected.

  1-17 is a figure for demonstrating one Embodiment by this invention. Among these, FIG. 1 is a diagram schematically showing the touch panel device together with an image display mechanism, FIG. 2 is a plan view showing the touch panel device, and FIGS. 3 and 4 are diagrams illustrating the layer configuration of the touch panel device. 5 to 7 are plan views showing mesh patterns formed by the detection electrodes of the touch panel sensor, and FIGS. 8 and 9 are diagrams for explaining an example of a method for designing a mesh pattern of a conductor mesh. . 10 to 14 are photographs relating to a mesh pattern for explaining a method for evaluating a mesh pattern of a conductor mesh, and FIGS. 15, 16 and 18 are graphs related to the power spectrum of the mesh pattern. FIG. 17 is a plan view showing a regular pattern identified from the power spectrum of the mesh pattern.

  As shown in FIG. 1, the touch panel device 20 is used in combination with an image display mechanism (for example, a liquid crystal display device) 12 to constitute a display device 10. The image display mechanism 12 includes a display area A1 that can display an image, and a non-display area (also referred to as a frame area) A2 that is disposed outside the display area A1 so as to surround the display area A1. Yes. The touch panel device 20 includes a touch panel sensor 25, a transparent cover 22 disposed on the viewer side of the touch panel sensor 25, and a circuit (not shown) connected to the touch panel sensor 25. The transparent cover 22 forms a touch surface on which the touch panel device 20 detects the contact (approach) position of the external conductor. The transparent cover 22 is bonded to the touch panel sensor 25 via a bonding layer.

  The touch panel sensor 25 includes a position detection electrode substrate 30 having electrodes used for position detection. The position detection electrode substrate 30 is disposed at a position facing the display surface 12a of the image display mechanism 12, and has an electrode 40 for detecting the position. Hereinafter, an example in which the touch panel device 20 is configured as a projected capacitive coupling type touch panel device will be described.

  As shown in FIG. 2, the touch panel sensor 25 configured as a projected capacitive coupling system includes a first electrode 40 and a second electrode 50 that are spaced apart along the normal direction. As shown in FIG. 3, the projected capacitive coupling type touch panel sensor 25 may include two position detection electrode substrates 30a and 30b each having electrodes 40a and 40b. In the example illustrated in FIG. 3, the first position detection electrode substrate 30 a includes a base sheet 35 and a first electrode 40 a provided on the base sheet 35. Similarly, the second position detection electrode substrate 30 b includes a base sheet 35 and a second electrode 40 b provided on the base sheet 35.

  On the other hand, the projected capacitively coupled touch panel sensor 25 may have only a single position detection electrode substrate 30 as shown in FIG. The position detection electrode substrate 30 includes a single base sheet 35 and a first electrode 40a and a second electrode 40b provided on both sides of the base sheet 35, respectively.

  In the following, the layer configuration shown in FIG. 3 will be described. However, the first position detection electrode substrate 30a and the second position detection electrode substrate 30b are configured in the same manner in materials, layer configurations, dimensions, and the like, although the arrangement patterns and the like of the electrodes 40a and 40b in plan view are different. Can do. Therefore, the description common to the first position detection electrode substrate 30a and the second position detection electrode substrate 30b will be described using the reference numeral “30” without distinguishing between “first” and “second”.

  The base material sheet 35 used for the position detection electrode substrate 30 functions as a base material that supports the electrodes 40 a and 40 b and also functions as a dielectric in the touch panel sensor 25. As shown in FIG. 2, the base sheet 35 includes an active area Aa1 corresponding to a region where a contact (approach) position of an external conductor (for example, a finger) can be detected, and an inactive area Aa2 adjacent to the active area Aa1. , Including. As shown in FIG. 1, the active area Aa1 of the position detection electrode substrate 30 occupies an area facing the display area A1 of the image display mechanism 12. On the other hand, the non-active area Aa2 is formed in a frame shape so as to surround the rectangular active area Aa1 from the four sides. The inactive area Aa2 is formed in a region facing the non-display region A2 of the image display mechanism 12.

  The substrate sheet 35 is transparent or translucent so that the image of the image display mechanism 12 can be observed through the active area Aa1. The substrate sheet 35 preferably has a transmittance in the visible light region of 80% or more, and more preferably 84% or more. The visible light transmittance of the substrate sheet 35 is measured using a spectrophotometer (manufactured by Shimadzu Corporation “UV-3100PC”, JIS K0115 compliant product) within a measurement wavelength range of 380 nm to 780 nm. It is specified as an average value of transmittance at each wavelength.

  The base material sheet 35 can be comprised from the glass and resin film which can function as a dielectric material, for example. As the resin film, various resin films used as the base material of the optical member can be suitably used. As an example, an optically isotropic film having no birefringence, typically a film made of a cellulose ester typified by triacetyl cellulose can be used as the substrate sheet 35. On the other hand, an optically isotropic film having birefringence can also be used as the substrate sheet 35. For example, a polyester film such as polyethylene terephthalate (PET) that is inexpensive and excellent in stability can be used as the base sheet 35. Polyester films have the advantage that they are less hygroscopic and less likely to be deformed even in high temperature and high humidity environments.

  Next, the first electrode 40a and the second electrode 40b provided on the base sheet 35 will be described. As shown in FIG. 2, the first electrode 40a includes a first detection electrode 45a used for position detection, and a first extraction electrode (extraction wiring) 42a connected to the first detection electrode 45a. . Similarly, the second electrode 40b includes a second detection electrode 45b used for position detection, and a second extraction electrode (extraction wiring) 42b connected to the second detection electrode 45b. Each detection electrode 45a, 45b is arranged in the active area Aa1 so as to form a pattern. On the other hand, the extraction electrodes 42a and 52a are disposed in the inactive area Aa2.

  In the following description, the description common to the first electrode 40a and the second electrode 40b will be described using the symbol “40” without distinguishing between “first” and “second”. Similarly, the description common to the first detection electrode 45a and the second detection electrode 45b will be described using the symbol “45” without distinguishing between “first” and “second”, and the first The description common to the extraction electrode 42a and the second extraction electrode 42b will be described using the symbol “42” without distinguishing between “first” and “second”.

  One or two extraction electrodes 42 are provided for each of the detection electrodes 45 depending on the detection method of the contact position. Each extraction electrode 42 is connected to a corresponding detection electrode 45 to form a wiring. The extraction electrode 42 extends from the corresponding detection electrode 45 to the edge of the base sheet 35 in the inactive area Aa <b> 2 of the base sheet 35. A terminal portion 43 is formed at the end of the extraction electrode 42 opposite to the detection electrode 45. The extraction electrode 42 is connected to a control circuit (not shown) at the terminal portion 43 via an external connection wiring (for example, FPC) (not shown).

  In the example shown in FIG. 3, the first detection electrodes 45 a and the second detection electrodes 45 b are arranged in different predetermined patterns on the viewer-side surface of the corresponding base material sheet 35. Specifically, as shown in FIG. 2, the first detection electrodes 45a have a rectangular outline shape, extend linearly, and are arranged in a direction intersecting the longitudinal direction thereof. Similarly, the second detection electrodes 45b also have a rectangular outline shape, extend linearly, and are arranged in a direction intersecting the longitudinal direction. However, the arrangement direction of the first detection electrodes 45a and the arrangement direction of the second detection electrodes 45b are not parallel. In the illustrated example, the first detection electrodes 45a are arranged vertically in FIG. 2 and extend linearly in a direction perpendicular to the arrangement direction (left and right in FIG. 2) so as to have a stripe shape. Further, the second detection electrodes 45b are also arranged in the left and right directions in FIG. 2 so as to have a stripe shape, and extend linearly in a direction (up and down in FIG. 2) perpendicular to the arrangement direction. Furthermore, the arrangement direction of the first detection electrodes 45a and the arrangement direction of the second detection electrodes 45b are orthogonal to each other.

  The detection electrode 45 is provided to detect an electromagnetic change or a change in capacitance that occurs when an external conductor comes into contact with or approaches the touch panel sensor 25. Therefore, the detection electrode 45 is required to have conductivity that allows a current caused by an electromagnetic change or a change in capacitance to flow at a detectable level. As a material for constituting such a detection electrode 45, a metal material having excellent conductivity, for example, gold, silver, copper, platinum, aluminum, chromium, molybdenum, nickel, titanium, palladium, indium, and these One or more of these alloys can be used.

  On the other hand, these metal materials have a light shielding property against visible light. Therefore, the detection electrode 45 includes a conductor mesh 46 in which conductive wires are arranged in a mesh pattern 50 that defines a large number of opening regions 51, as shown in FIGS. In particular, in the example shown in FIG. 2, each detection electrode 45 is formed of a conductor mesh 46 formed in an elongated region. The line width of the conducting wire forming the conductor mesh 46 can be set to 1 μm or more and 30 μm or less. The opening ratio of the conductor mesh 46 can be 90% or more and 99% or less. Moreover, the pitch of the opening area | region 51 can be 200 micrometers or more and 1000 micrometers or less.

  A mesh-like conductor is provided over the entire active area Aa1, and a plurality of detection electrodes 45 of each electrode 40 are formed by disconnecting the conductive wire forming the mesh-like conductor corresponding to the outline of the detection electrode 45 of each electrode 40. Each of the conductive meshes 46 may be formed. In other words, the conductor mesh 46 corresponds to each of a plurality of mesh patterns that are partitioned by breaking the mesh-like conductor that spreads throughout the active area Aa1 at the break portion. Each conductor mesh 46 forms a mesh pattern 50 that defines a number of open areas 51. As shown in FIGS. 5 to 7, the mesh pattern 50 is formed of a large number of connecting elements 53 that extend between two branch points 52 and define an open region 51. That is, the branch point 52 is a point where one end of the three or more connection elements 53 is joined.

By the way, as shown in FIG. 19, pixels P for forming an image are regularly arranged in the display area A <b> 1 of the image display mechanism 12 arranged so as to overlap the touch panel sensor 25. In general, pixels P are arranged at a constant pitch both in the horizontal direction (direction d _x in FIG. 19) in the installed state of the image display mechanism 12 and in the direction d _y (eg, the vertical direction) orthogonal to the horizontal direction. ing. As in the example shown in FIG. 19, each pixel P generally includes a plurality of sub-pixels RP, GP, and BP. When the touch panel sensor 25 having the conductor mesh 46 is stacked on the image display mechanism 12 having the pixel arrangement, when the opening areas 51 of the conductor mesh 46 are regularly arranged, the regular (periodic) of the pixels P are arranged. There is a possibility that a striped pattern resulting from the pattern and the arrangement pattern of the opening areas 51 of the conductor mesh 46, that is, moire, is visually recognized.

  For this reason, it has been considered that making the pattern of the conductor mesh irregular is effective for making the moire invisible. However, according to the study by the present inventors, even if the shape and arrangement pitch of the pattern of the conductor mesh are simply made irregular, the moire cannot always be made sufficiently inconspicuous. Further, even if the regularity of the arrangement of the opening areas 51 of the conductor mesh 46 is largely lost, that is, the opening areas 51 are irregularly arranged, even if the moire can be made inconspicuous, the opening areas 51 There is also a possibility that the unevenness in density due to the density variation is visually recognized. And as explained in the background section, various countermeasures for invisibility of moire or shading unevenness have been studied, but both moire and shading unevenness have not been effectively inconspicuous.

  Then, if the mesh pattern 50 formed by the detection electrode 45 is a pattern in which the regularity of the regular pattern is broken to some extent, the inventor makes both moire and shading unevenness inconspicuous. I thought it was possible. As a result of further examination on this point, the present inventor finally obtained a Fourier transform power spectrum image of the mesh pattern 50 formed by the detection electrode 45 of the touch panel sensor 25 that satisfies the predetermined condition. In some cases, it has been found that it is possible simultaneously to make the moire very inconspicuous and to make the uneven density inconspicuous very effectively.

  In the following, first, the conductor mesh of the detection electrode 45 in which the mesh pattern 50 is formed as a pattern in which the regularity of the regular pattern is broken to some extent will be described. And after that, the conditions which the mesh pattern 50 formed by eliminating the regularity of the pattern having regularity should satisfy in order to effectively invisible both moire and shading unevenness will be described.

  FIG. 5 shows an example of the conductor mesh 46 that forms the first detection electrode 45a, and FIG. 6 shows an example of the conductor mesh 46 that forms the second detection electrode 45b. Both patterns of these conductor meshes 46 are a reference pattern 60 (see FIGS. 8 and 9) formed from a plurality of line segments 63 extending between two intersections 62 and defining an open region (opening) 61. (See below). More specifically, the mesh pattern 50 of these conductor meshes 46 includes a reference pattern 60 in which the opening regions 61 are regularly arranged. In other words, the reference pattern 60 in which the opening regions 61 are arranged with periodicity. As a basis, the shape of the opening area 61 is changed to such an extent that the moire can be sufficiently invisible while maintaining the uniformity of the arrangement position of the opening area 61 so as not to cause unevenness of shading. It is determined by varying the opening area.

  In the example shown in FIGS. 5 and 6, the conductive mesh 46 forming the first detection electrode 45a and the conductive mesh 46 forming the second detection electrode 45b are based on the reference pattern 60 of the same pattern. The pattern has been determined. Therefore, as shown in FIGS. 5 and 6, in a state where the regularity of the reference pattern 60 is not greatly broken, the conductor mesh 46 forming the first detection electrode 45 a and the conductor mesh 46 forming the second detection electrode 45 b. Is almost the same pattern.

  In the example shown in FIG. 2, the conductor mesh 46 forming the first detection electrode 45a and the conductor mesh 46 forming the second detection electrode 45b are disposed so as to overlap each other. In the overlapping portion in this way, the conductive mesh 46 forming the first detection electrode 45a and the conductive mesh 46 forming the second detection electrode 45b are such that the reference pattern 60 relating to each of the conductive mesh 46 in the arrangement direction of the opening regions 61 They are positioned with respect to each other so as to be displaced by a length that is half the arrangement pitch of the opening regions 61. As a result, as shown in FIG. 7, the conductor mesh 46 forming the first detection electrode 45a and the conductor mesh 46 forming the second detection electrode 45b leave a certain degree of regularity in a state where they are overlapped with each other. Pattern is formed.

  The moire pattern includes a mesh pattern 50 formed by superimposing a mesh pattern formed by the first detection electrode 45a and a mesh pattern formed by the second detection electrode 45b, and a regular pattern of other members (for example, an image display mechanism). This is caused by interference between the mesh pattern 50 formed by the detection electrode 45 of each electrode 40 and a regular pattern of other members. Similarly, shading unevenness is also caused by local non-uniformity of the mesh pattern 50 formed by superimposing the mesh pattern formed by the first detection electrode 45a and the mesh pattern formed by the second detection electrode 45b. It can also be caused by local non-uniformity of the mesh pattern 50 formed by the detection electrode 45 of each electrode 40. Therefore, when the conditions related to the Fourier transform power spectrum image to be described later are satisfied by the mesh pattern 50 formed by overlapping the mesh pattern formed by the first detection electrode 45a and the mesh pattern formed by the second detection electrode 45b, It is effective in making both moiré and shading unevenness inconspicuous, and even when any one of the mesh patterns 50 formed by the detection electrodes 45 constituting each electrode 40 is independently filled with one or more, moire and shading This is effective in making both of the unevenness inconspicuous.

  Next, a specific example of the method for determining the pattern of the conductor mesh 46 described above will be described. In the method described below, a reference pattern 60 formed from a plurality of line segments 63 extending between two intersections 62 and defining an open region 61 is determined, and based on the intersections 62 of the reference pattern 60. Determining the position of the branch point 52 of the mesh pattern 50, and determining the position of the connection element 53 of the mesh pattern 50 based on the determined branch point 52 and the line segment 63 of the reference pattern 60. ing. Hereinafter, each step will be described in order.

First, in the step of determining the reference pattern 60, a regular pattern that is the basis of the conductor mesh 46, that is, the reference pattern 60 is determined. The reference pattern 60 determined here is formed from a plurality of line segments 63 extending between two intersections 62 and defining an open region 61. In the reference pattern 60 shown in FIGS. 8 and 9, the opening regions 61 having a fixed shape are regularly arranged in two or more directions d _r1 and d _r2 intersecting each other. The reference pattern 60 may include a plurality of types of opening regions 61, and the various opening regions 61 may be regularly arranged in two or more directions where they intersect.

In the reference pattern 60 shown in FIG. 8 and FIG. 9, a certain rectangular opening area 61 is laid out without any gap. The opening regions 61 are arranged at a constant pitch in the first reference direction _dr1 and the second reference direction _dr2 that intersect each other. Especially, the reference pattern 60 shown is, from each of the plurality of first straight line 66a which are arranged at a constant pitch p _b1 in the direction perpendicular to the linearly extending and first reference direction d _r1 in a first reference direction d _r1 A first parallel line group 66 each extending linearly in the second reference direction _dr2 and arranged in a direction orthogonal to the second reference direction _dr2 at a constant pitch _pr2 equal to the constant pitch _pr1 . And a second parallel line group 67 composed of second straight lines 67a. As a result, all the opening regions 61 included in the reference pattern 60 are formed in the same quadrangular shape, in particular, a rhombus shape.

As shown in FIG. 9, in the illustrated example, the reference pattern related to the mesh pattern formed by the first detection electrode 45a and the reference pattern related to the mesh pattern formed by the second detection electrode 45b are the same pattern. ing. As shown in FIG. 9, the reference patterns related to the mesh patterns of the detection electrodes 45a and 45b are arranged so that the respective first reference directions _dr1 are parallel to each other. The reference patterns related to the mesh patterns of the detection electrodes 45a and 45b are arranged so that the second reference directions _dr2 are parallel to each other. The reference pattern related to the mesh pattern of each of the detection electrodes 45a and 45b is that the group of the first parallel line groups 66 is half the constant pitch p _r1 (p _r1 / 2) in the direction orthogonal to the first reference direction _dr1. Are just offset from each other. In addition, the reference pattern related to the mesh pattern of each of the detection electrodes 45a and 45b is such that each second parallel line group 67 has a half (p _r2 / 2) of a constant pitch p _{r2 in} a direction orthogonal to the second reference direction _dr2. ) Are just offset from each other. According to the determination of the reference pattern 60, the two conductor meshes 46 produced based on the reference pattern 60 are overlapped with each other, and the open region remains with a certain degree of regularity, while being constant. A mesh pattern 50 having a non-existent shape is shown. That is, the conductor mesh 46 exhibits a pattern in which the opening regions are dispersed to a certain degree even in a state where they are not only separated but also overlapped.

Incidentally, in general, the moire caused by interference with the conductive mesh 46 of the pixel array and the touch panel sensor 25 of the image display system 12 from the perspective of invisible, the arrangement direction of the pixels in the image display mechanism 12 d _x, to d _y, It is preferable to incline the arrangement direction of the opening areas 51 of the touch panel sensor 25. On the other hand, when the present inventors have repeated experiments, in order to invisible moire with square lattice arrayed pixels P shown in FIG. 19, further, even for diagonal d _o of the pixel, the touch panel It was effective to incline the arrangement direction of the opening regions 51 of the sensor 25. This is because, as shown in FIG. 19, the light blocking portions 13a are arranged at regular intervals with the wide width portions 13a of the light blocking portions (for example, black matrix) 13 defining the pixels P arranged at diagonal positions of the pixels P. This is because moire between the 13 thick portions 13a and the opening region 51 is likely to occur.

A general pixel P arranged in a square lattice has a square shape in plan view. When using such a pixel P, the diagonal _{d o} is, 45 ° inclined with respect to the pixel arrangement direction _d x, _{d y.} As a result of confirmation by the present inventor, in order to make the moire with the square pixel P invisible, the arrangement direction of the opening region 51 is set to one of the orthogonal pixel arrangement directions d _x and d _dy d _x . The angle formed with respect to it is preferably 30 ° or more and 40 ° or less, more preferably 33 ° or more and 37 ° or less, and most preferably 35 °. In other words, in order to invisible moire between the pixel P of a square shape, arrangement direction of the opening area 51, the arrangement direction d _x of the pixel to be _orthogonal, the angle formed with respect to the other d _y of d _y 50 The angle is preferably from 60 ° to 60 °, more preferably from 53 ° to 57 °, and most preferably from 55 °.

On the other hand, in the pattern determination method of the conductor mesh 46 described here, the opening area 51 of the conductor mesh 46 generally follows the arrangement direction of the opening areas 61 of the reference pattern 60. And the arrangement direction of the opening area | region 61 in the reference pattern 60 turns into 1st reference direction _dr1 and 2nd reference direction _dr2 (or direction orthogonal to these). Accordingly, the first reference direction _{d r1} and the second reference direction _{d r2} orienting of the opening region 61 included in the reference pattern 60, the arrangement direction _d x of the pixel P that is orthogonal with respect to one _{d x} of _{d y} It is preferable that the angle is 30 ° or more and 40 ° or less, more preferably 33 ° or more and 37 ° or less, and the angles θ _r1x and θ _r2x of 35 ° are formed as shown in FIGS. 8 and 9. Most preferred. Therefore, the angle theta _rx forming first reference direction _{d r1} and the second reference direction _{d r2} are relative to each other is preferably 60 ° or more than 80 °, more preferably 66 ° or more 74 ° or less, As shown in FIGS. 8 and 9, the angle is most preferably 70 °. The first reference direction d _r1 and the second reference direction d _r2 orienting of the opening region 61 included in the reference pattern 60, 60 ° 50 ° or more with respect to the other d _y of the pixel arrangement direction orthogonal It is preferable to make the following angles, more preferably to make an angle of 53 ° or more and 57 ° or less, and most preferable to _make the angles θ _r1y and θ _r2y of 55 ° as shown in FIGS.

  Next, the process of determining the position of the branch point 52 based on the intersection 62 of the reference pattern 60 will be described. In this step, the position of one branch point 52 is determined from one intersection point 62 of the reference pattern 60. Specifically, each branch point 52 is arranged on the corresponding intersection 62 of the reference pattern 60 or at a position shifted from the corresponding intersection 62 by a length equal to or less than a predetermined length. At this time, the shape of the opening region 51 of the finally obtained conductor mesh 46 does not become constant by irregularly determining the amount of deviation and the direction of deviation from the corresponding intersection 62 of each branch point 52. Moire can be effectively inconspicuous. In addition, when the deviation amount selected irregularly becomes 0, the branch point 52 may be positioned on the corresponding intersection point 62.

It should be noted that the amount of deviation of each branch point 52 from the corresponding intersection point 62 is preferably less than half the arrangement pitch of the opening regions 61 in order to avoid the connection element 53 from contacting another connection element. . This is because, when one connection element 53 overlaps with another connection element, the portion is visually recognized and may cause uneven shading. Specifically, in order to avoid the connection element 53 from coming into contact with other connection elements, the deviation amount of each branch point 52 from the corresponding intersection 62 is the first in the direction orthogonal to the first reference direction _dr1 . It can be less than half of the arrangement pitch p _r1 of the parallel line group 66 and less than half of the arrangement pitch p _r2 of the second parallel line group 67 in the direction orthogonal to the second reference direction _dr2 .

Further, as described above, in the illustrated example, the reference pattern related to the mesh pattern of each of the detection electrodes 45a and 45b is such that each first parallel line group 66 is arranged in an arrangement direction orthogonal to the first reference direction _dr1 . It is displaced by half the predetermined pitch _{p r1 (p 1/2)} . In addition, reference pattern for the mesh pattern of the detection electrodes 45a, 45b, each second group of parallel lines 67, the arrangement direction perpendicular to the second reference direction _{d r2,} half of the predetermined pitch _{p r2 (p r2} / 2) It is displaced by a distance. In such an example, in order to avoid contact between the connection element 48 related to the conductive mesh 46 of the first detection electrode 45a and the connection element 58 related to the conductive mesh 46 of the second detection electrode 45b, The amount of deviation of the branch point 52 from the corresponding intersection point 62 is preferably less than ¼ of the arrangement pitch of the opening regions 61. If the connection element 48 related to the mesh pattern 50 of the first detection electrode 45a and the connection element 58 related to the mesh pattern 50 of the second detection electrode 45b come into contact with each other, this portion is visually recognized, which causes uneven density. It is because there is a possibility that it will end. Specifically, in order to avoid contact between the connection element 48 related to the mesh pattern 50 of the first detection electrode 45a and the connection element 58 related to the mesh pattern 50 of the second detection electrode 45b, The amount of deviation from the corresponding intersection point 62 is less than 1/4 of the arrangement pitch p _r1 of the first parallel line group 66 in the direction orthogonal to the first reference direction _dr1, and the direction orthogonal to the second reference direction _dr2 In the second parallel line group 67, the arrangement pitch p _r2 may be less than ¼.

Furthermore, instead of determining both the amount of deviation from the corresponding intersection 62 and the direction of deviation for each branch point 52, each branch point 52 is set in two preset directions from the corresponding intersection 62. The amount of deviation may be determined. As an example, the arrangement direction _d x of the pixel P of the image display system 12, the deviation amount [delta] _rx from the corresponding intersection 62 to _{d y,} [delta] _ry (see FIG. 8), as will be determined for each branch point 52 It may be. In this example, from the viewpoint of suppressing the occurrence of shading unevenness, the arrangement pitch p _rx of the opening regions 61 along one arrangement direction d _x of the pixels P is less than a certain ratio (for example, 15% or less) and the occurrence of moire is prevented. From this viewpoint, the shift amount δ _rx is determined so as to be equal to or greater than a certain ratio (for example, 2% or more) of the arrangement pitch p _rx of the opening regions 61 along one arrangement direction d _x of the pixels P, and certain percentage or less (e.g., less 1530%) and and the pixel from the viewpoint of preventing occurrence of moire arrangement pitch p _ry open area 61 along the occurrence of uneven density from the viewpoint of suppressing the other arrangement direction d _y of the pixel P by so more than a certain percentage of the arrangement pitch p _ry open area 61 along one of the arrangement direction d _y of P (e.g., 2% or more) and so as to shift amount [delta] _ry is determined, pairs It may impose restrictions on the amount of deviation of the branching point 52 from the intersection 62.

  Next, the process of determining the position of the connection element 53 will be described. When the position of the branch point 52 in the conductor mesh 46 is determined as described above, the position of the connection element 53 is then determined based on the determined branch point 52. Specifically, one connection element of the conductor mesh 46 extends between the two branch points 52 respectively corresponding to the two intersections 62 located at both ends of a certain line segment 63 of the reference pattern 60. 53 position is determined. The path of the connecting element 53 between the two branch points 52 may be a straight line, a curved line, a broken line, or a combination of a straight line and a curved line. Further, the line width of the connection element 53 can be set to 0.2 μm or more and 2 μm or less as described above, or may be a thickness outside this range.

  In this way, the mesh pattern 50 of the conductor mesh 46 that forms the detection electrode 45 of the electrode 40 is designed. Since the position of the branch point 52 of the mesh pattern 50 is determined based on the position of the intersection point 62 of the reference pattern 60 having regularity, the opening region 51 is uniformly uniform in the obtained conductor mesh 46. It is possible to disperse and suppress the occurrence of shading unevenness. However, the position of the branch point 52 is shifted from the position of the corresponding intersection point 62 by an amount within a predetermined range selected irregularly. Therefore, regularity or regularity of the shape or opening area of the opening region 51 is lost in the obtained conductor mesh 46, and a problem due to moire can be avoided.

  The conductor mesh 46 having the mesh pattern 50 determined as described above is produced on the base sheet 35 by patterning a metal thin film formed on the base sheet 35 using a photolithography technique. obtain.

  As described above, the mesh pattern 50 formed by erasing the regularity of the pattern having regularity to some extent can make both moire and shading unevenness inconspicuous. However, if the regularity is greatly deteriorated, the unevenness of density is visually recognized and becomes a problem. If the regularity is not fully lost, moire is visually recognized. As a result of repeated studies, the present inventor has finally obtained a Fourier transform power spectrum image of the mesh pattern 50 formed by the detection electrode 45 of the touch panel sensor 25 that satisfies a predetermined condition. It has been found that it is possible simultaneously to make moire very inconspicuous and to make shading unevenness very inconspicuous. In other words, it was quantitatively evaluated how much the regularity was broken, and it was found that both moire and shading unevenness can be effectively inconspicuous.

More specifically, the standard deviations σ _p1 and σ _p2 related to the mesh pattern 50 and the standard deviations σ _ap1 and σ _ap2 related to the rule pattern 70 related to the mesh pattern 50 _satisfy the following conditions (a) and (b). When satisfying, both moire and shading unevenness could be effectively made inconspicuous.
1.02 ≦ σ _p1 / σ _ap1 ≦ 1.16 (a)
1.02 ≦ σ _p2 / σ _ap2 ≦ 1.16 (b)
Here, the standard deviations σ _p1 and σ _{p2 related} to the mesh pattern 50 are based on the Fourier transform power spectrum image of the mesh pattern 50, and are used as an index indicating the degree of regularity of the mesh pattern 50 as a specific power spectrum integration of the mesh pattern 50. The standard deviation for the value. On the other hand, the regular pattern 70 is specified as a regular pattern similar to the mesh pattern 50 from the Fourier transform power spectrum image of the mesh pattern 50. The standard deviations σ _ap1 and σ _ap2 related to the regular pattern 70 are specified based on the Fourier transform power spectrum image of the regular pattern 70 under the same conditions as the standard deviations σ _p1 and σ _p2 related to the mesh pattern 50.

Therefore, the ratio of the standard deviations σ _p1 , σ _p2 for the mesh pattern 50 to the standard deviations σ _ap1 , σ _ap2 for the regular pattern 70 _indicates how regular the mesh pattern 50 is from the regular pattern 70 similar to the mesh pattern 50. It becomes an index indicating whether it has disappeared. When this index is within a predetermined range, the mesh pattern 50 becomes a pattern in which regularity is broken from a regular pattern to an appropriate degree, and it is considered that both moire and shading unevenness can be appropriately dealt with. It is done.

  Hereinafter, the conditions that the mesh pattern 50 formed by eliminating the regularity of the regular pattern to satisfy both the moire and the shading unevenness effectively will be described in detail.

First, a method for specifying the standard deviations σ _p1 and σ _{p2 for} the mesh pattern 50 will be described with reference to FIGS. 10-15, the conductor mesh 46 is actually produced with the mesh pattern 50 of the first detection electrode 45a determined by the above-described method described with reference to FIGS. 8 and 9, and the production is performed. This is data on the conductive mesh 46 of the first detection electrode 45a.

First, the first standard deviation σ _p1 is an integrated value at each angle of the power spectrum of the mesh pattern 50 obtained by subjecting the scan data of the mesh pattern 50 created by using a planar scanner to Fourier transform and polar coordinate conversion. In the distribution (see FIG. 15), within the range of 60 ° centered on the first peak angle θ _p1 [°] where the power spectrum integrated value becomes the largest within the range of 0 ° to less than 180 ° (θ _p1 ± 30 [ °]) is the standard deviation of the integrated power spectrum. The second standard deviation σ _p2 is a second peak angle θ _p2 [°] at which the power spectrum integrated value becomes the second largest in the range of 0 ° or more and less than 180 ° in the distribution of the power spectrum integrated value of the mesh pattern 50. _Is the standard deviation of the integrated value of the power spectrum within a range of 60 ° (θ _p2 ± 30 [°]).

Therefore, when specifying the standard deviations σ _p1 and σ _p2 related to the mesh pattern 50, first, the conductor mesh 46 is scanned with a planar scanner, thereby creating scan data related to the mesh pattern 50 as a two-dimensional image. At this time, in consideration of the pitch of the opening area 51 of the touch panel sensor 25 actually distributed, the area of the conductor mesh 46 for which the scan data of the mesh pattern 50 is to be created is an area of 3 cm × 3 cm or more. It is preferable to do. Moreover, it is preferable to adjust the resolution so that the line width of the conducting wire (connecting element 53) forming the mesh pattern 50 is configured by a plurality of pixels. If the resolution is such that the line width is composed of a plurality of pixels, it is possible to effectively prevent the disconnection portion that does not exist in the actual object from being formed in the scan data. FIG. 10 shows a part of the scan data of the mesh pattern 50.

  By performing image processing on the scan data of the mesh pattern 50, a Fourier transform power spectrum image of the mesh pattern 50 is created. At this time, in order to improve the creation accuracy of the Fourier transform power spectrum image, it is preferable to perform some processing on the image.

  For example, it is preferable to perform binarization processing on the scan data in order to remove low frequency components other than the metal conductors forming the conductor mesh 46 from the scan data. Illumination unevenness that inevitably occurs can be exemplified as the low frequency component to be removed. FIG. 11 shows image data obtained by binarizing the image data shown in FIG.

  Further, in order to improve the creation accuracy of the Fourier transform power spectrum image, it is also effective to perform a thinning process before the Fourier transform. In particular, as described above, when the line width of the conducting wire (connecting element 53) forming the mesh pattern 50 is composed of a plurality of pixels, the thinning process is effective.

  FIG. 12 shows scan data after the binarization process and the thinning process. This scan data is image data of 4155 μm × 4155 μm of the conductor mesh 46 of the first detection electrode 45a actually produced. FIG. 13 shows a Fourier transform power spectrum image obtained by performing Fourier transform on the scan data shown in FIG. FIG. 14 shows the Fourier transform power spectrum image of FIG. The coordinate systems in FIGS. 12 to 14 are set similarly to each other, and are also set in the same manner as the coordinate systems shown in FIGS. The setting of the coordinate system in FIG. 14 is as shown in FIG.

From the image data of FIGS. 13 and 14, the distribution of the power spectrum of the mesh pattern 50 at each angle θ [°] can be specified. Next, an integrated value of the power spectrum is specified as a value obtained by integrating the power spectrum for each angle θ [°]. FIG. 15 shows the integrated value distribution at each angle of the power spectrum of the mesh pattern. In this power spectrum integrated value distribution, the angle at which the power spectrum integrated value is the largest within the range of 0 ° to less than 180 ° is the first peak angle θ _p1 [°], and the power is within the range of 0 ° to less than 180 °. The angle at which the spectrum integrated value becomes the second largest is defined as the second peak angle θ _p2 [°]. However, in the power spectrum integrated value distribution, when it is not possible to distinguish between the angle at which the integrated value is the largest and the angle at which the second surface is increased, either one is the first peak angle θ _p1 and the other is the second peak. The angle θ _p2 may be set.

Note that in order to specify the first peak angle θ _p1 and the second peak angle θ _p2 , and later described standard deviations σ _p1 and σ _p2 with high accuracy, several processes are performed on the integrated value distribution. Also good. For example, the power spectrum integrated value distribution may be subjected to a blurring process in a range of ± 10 ° around, and a specific high-frequency component may be removed. According to such processing, the maximum value appears more clearly in the integrated value distribution of the power spectrum. A Gaussian filter can be used for the blurring process. The power spectrum integrated value distribution shown in FIG. 15 is an integrated value distribution after performing blurring processing within an angle range of ± 10 ° using a Gaussian filter.

In the integrated value distribution of FIG. 15, the first peak angle θ _p1 is 125 °, and the second peak angle θ _p2 is 55 °. In the integrated value distribution of the power spectrum of the mesh pattern 50, it means that the metal conductors forming the mesh pattern 50 are arranged in the angle direction in which the peak of the integrated value appears. Therefore, since the peak angles θ _p1 and θ _p2 appear at 55 ° and 125 °, the target mesh pattern 50 is the same pattern as the conductor mesh 46 shown in FIGS. , And a pattern similar to the reference pattern 60 shown in FIGS. 8 and 9 is predicted.

From the viewpoint of making the moire between the image display mechanism 12 shown in FIG. 19 inconspicuous, the angle θ _rx formed by the first reference direction _dr 1 and the second reference direction _dr 2 of the reference pattern 60 with respect to each other. However, it is preferably 60 ° or more and 80 ° or less, more preferably 66 ° or more and 74 ° or less, and most preferably 70 °. From this point of view, in the integrated distribution of the power spectrum of the mesh pattern 50, the first peak angle θ is assumed on the assumption that there are only two power spectrum integrated values within the range of 0 ° to less than 180 °. It is preferable that _p1 and the second peak angle θ _p2 satisfy the following condition:
60 ° ≦ | θ _p1 −θ _p2 | ≦ 80 °, or 100 ° ≦ | θ _p1 −θ _p2 | ≦ 120 °
It is more preferable to satisfy the following conditions:
66 ° ≦ | θ _p1 −θ _p2 | ≦ 74 ° or 106 ° ≦ | θ _p1 −θ _p2 | ≦ 114 °
Furthermore, it is most preferable to satisfy the following conditions.
| Θ _p1 −θ _p2 | = 70 °, or | θ _p1 −θ _p2 | = 110 °

As described above, the first standard deviation σ _p1 is the standard of the power spectrum integrated value of the mesh pattern 50 within the range of 60 ° (θ _p1 ± 30 [°]) with the first peak angle θ _p1 as the center. Deviation value. Accordingly, in the example shown in FIG. 15, the first standard deviation σ _p1 is a standard deviation value of the power spectrum integrated value within a range of 95 ° to 155 °. On the other hand, the second standard deviation σ _p2 is a standard deviation value of the integrated power spectrum value of the mesh pattern 50 within a range of 60 ° (θ _p2 ± 30 [°]) with the second peak angle θ _p2 as the center. It is. Therefore, in the example shown in FIG. 15, the second standard deviation σ _p2 is a standard deviation value of the power spectrum integrated value within a range of 25 ° to 85 °. If the first standard deviation σ _p1 and the second standard deviation σ _p2 are small, the metal conductors forming the target mesh pattern 50 are regularly arranged in a direction corresponding to the first peak angle θ _p1 or the second peak angle θ _p2. That is, it means that the regularity of the target mesh pattern 50 is strong. On the contrary, if the first standard deviation σ _p1 and the second standard deviation σ _p2 are large, the metal conductive wire forming the target mesh pattern 50 is in the direction corresponding to the first peak angle θ _p1 or the second peak angle θ _p2 . Means that the regularity of the target mesh pattern 50 is weak.

  Next, a method for specifying the rule pattern 70 will be described. As described above, the regular pattern 70 is specified as a regular pattern similar to the mesh pattern 50 from the Fourier transform power spectrum image of the mesh pattern 50. For example, when the mesh pattern 50 is determined by the above-described method described with reference to FIGS. 8 and 9, the specification of the regular pattern 70 is a regular basis that is used as a basis for determining the mesh pattern 50. The reference pattern 60 is estimated.

The regular pattern 70 has a first peak angle θ _p1 and a second peak angle θ _p2 in the integrated distribution of power spectra of the mesh pattern 50, and a distribution of the power spectrum of the mesh pattern 50 at the first peak angle θ _{p1 with} respect to the spatial frequency. In the distribution with respect to the spatial frequency of the power spectrum of the mesh pattern 50 at the first spatial frequency forming the peak (maximum value) of the first power spectrum located on the higher frequency side than the fundamental frequency and the second peak angle _θp2 . And a second spatial frequency forming a first peak located on the higher frequency side than the fundamental frequency. More specifically, the rule pattern 70 sets the coordinate system in the same manner as when the Fourier transform power spectrum image of the mesh pattern 50 is specified from the scan data of the mesh pattern 50, and the first peak angle θ _p1 [ °] in a direction corresponding to the first spatial frequency and a second line frequency in the direction corresponding to the second peak angle θ _p2 [°] in polar coordinates. And a second straight line group 77 arranged at a constant pitch having a length corresponding to.

FIG. 16 shows the distribution of the power spectrum with respect to the spatial frequency in the direction of 55 ° in polar coordinates for the mesh pattern 50 targeted in FIGS. That is, FIG. 16 illustrates the distribution of the power spectrum of the mesh pattern 50 at the second peak angle θ _p2 at each spatial frequency. As described above, in the illustrated example, the region of the original conductor mesh 46 from which the Fourier transform power spectrum image is acquired is a region of 4155 μm × 4155 μm. The length corresponding to the fundamental frequency, that is, the wavelength at the fundamental frequency (1 [cycle] /4.155 [mm] = 0.24 [cycle / mm]) is 4155 μm. On the other hand, in the power spectrum distribution of FIG. 16, the second spatial frequency at which the first power spectrum peak located on the higher frequency side than the fundamental frequency appears is 1.9976 [cycle / mm]. Therefore, the wavelength at the second spatial frequency is approximately 500.6 μm = 1000 μm / 1.9976 periods. As shown in FIG. 17, the arrangement direction d _aa2 of the second straight line group 77 is opposite to the x-axis direction that is the reference direction (0 ° direction) in polar coordinates by 55 ° that is the second peak angle θ _p2. The direction is inclined in the clockwise direction. The second straight line 77a which forms a second linear group 77, in its arrangement direction _{d aa2,} at a pitch _{P a2} of 500.6μm as the wavelength at the second spatial frequency (length corresponding to the second spatial frequency) Arranged.

In the regular pattern 70 shown in FIG. 17, the first straight line group 76 specified in the same manner as the second straight line group 77 is also shown. In other words, the arrangement direction d _aa1 of the first straight line group 76 is inclined counterclockwise by 125 ° which is the first peak angle θ _p1 with respect to the x-axis direction which is the reference direction (0 ° direction) in polar coordinates. It has become the direction. The first straight lines 76a forming the first straight line group 76 are arranged in the arrangement direction d _aa1 at the same pitch P _a1 as the length corresponding to the first spatial frequency.

Next, a method for specifying the standard deviations σ _ap1 and σ _ap2 related to the specified rule pattern 70 will be described. The standard deviations σ _ap1 and σ _ap2 related to the regular pattern 70 can be specified from the scan data of the mesh pattern 50 in substantially the same manner as the standard deviations σ _p1 and σ _p2 .

  First, the regular pattern 70 is produced as image data. At this time, it is preferable that the regular pattern 70 is produced as data of an area of 3 cm × 3 cm or more, like the scan data of the mesh pattern 50. The first straight line 76a of the first straight line group 76 and the second straight line 77a of the second straight line group 77 forming the regular pattern 70 are preferably thinned.

A Fourier transform power spectrum image of the regular pattern 70 is obtained by subjecting the image data of the regular pattern 70 to Fourier transform and polar coordinate transform. The first standard deviation σ _ap1 related to the regular pattern 70 is the first peak angle θ _p1 [°] (125 in the example shown in FIG. 15) in the integrated value distribution at each angle of the power spectrum of the regular pattern 70. _Is specified as the value of the standard deviation of the power spectrum integrated value within a range of 60 [deg.] ([Theta] _p1 ± 30 [[deg.]]). The second standard deviation σ _ap2 related to the regular pattern 70 is the second peak angle θ _p2 [°] (in the example shown in FIG. 15) in the integrated value distribution at each angle of the power spectrum of the regular pattern 70. Is specified as the value of the standard deviation of the integrated power spectrum value within the range of 60 ° (θ _p1 ± 30 [°]) centering around 55 °.

In order to specify the standard deviations σ _ap1 and σ _ap2 related to the regular pattern 70 with high accuracy, several processes may be performed. For example, the power spectrum integrated value distribution may be subjected to a blurring process in a range of ± 10 ° around, and a specific high-frequency component may be removed. According to such processing, the maximum value appears more clearly in the integrated value distribution of the power spectrum. A Gaussian filter can be used for the blurring process.

The standard deviations σ _p1 and σ _p2 related to the mesh pattern 50 specified as described above and the standard deviations σ _ap1 and σ _ap2 related to the rule pattern 70 related to the mesh pattern 50 are _expressed by the following conditions (a) and (b ), As described above, both moire and shading unevenness can be effectively made inconspicuous.
1.02 ≦ σ _p1 / σ _ap1 ≦ 1.16 (a)
1.02 ≦ σ _p2 / σ _ap2 ≦ 1.16 (b)

  As already described, the moire pattern is a mesh pattern formed by the first detection electrode 45a (for example, the mesh pattern in FIG. 5) and a mesh pattern formed by the second detection electrode 45b (for example, the mesh in FIG. 6). This is caused by interference between the mesh pattern 50 (for example, the mesh pattern of FIG. 7) on which the pattern is superimposed and a regular pattern of other members (for example, the arrangement pattern of the pixels P of the image display mechanism 12), and each electrode. This also occurs due to interference between the mesh pattern 50 (for example, the mesh pattern of FIG. 5 or the mesh pattern of FIG. 6) formed by the detection electrodes 45a and 45b of 40a and 40b and the regular pattern of other members. Similarly, shading unevenness is also caused by local non-uniformity of the mesh pattern 50 formed by superimposing the mesh pattern formed by the first detection electrode 45a and the mesh pattern formed by the second detection electrode 45b. This may also be caused by local non-uniformity of the mesh pattern 50 formed by the detection electrodes 45a and 45b of the electrodes 40a and 40b. The conditions (a) and (b) related to the Fourier transform power spectrum image of the mesh pattern are the meshes obtained by superimposing the mesh pattern formed by the first detection electrode 45a and the mesh pattern formed by the second detection electrode 45b. When it is satisfied by the pattern 50, it is effective for making both moire and shading unevenness inconspicuous, and by any one or more of the mesh patterns 50 formed by the detection electrodes 45a and 45b forming the electrodes 40a and 40b. Even when satisfied alone, it is effective in making both moire and shading unevenness inconspicuous.

  Here, an example of an experiment conducted by the present inventors will be described. First, conductor meshes according to samples 1 to 7 were produced.

  The conductor mesh of Sample 1 was the same mesh pattern as the reference pattern 60 shown in FIG. That is, a first parallel line group extending in a direction inclined by 145 ° with respect to the x-axis direction (reference direction) and a second parallel line group extending in a direction inclined by 35 ° with respect to the x-axis direction (reference direction). And a pattern consisting of The straight lines included in the first parallel line group are arranged at a pitch of 500 μm in a direction orthogonal to the longitudinal direction, and the straight lines included in the second parallel line group are arranged at a pitch of 500 μm in the direction orthogonal to the longitudinal direction. It was arranged in. Therefore, the mesh pattern of the conductor mesh of Sample 1 is a pattern in which certain rhombic opening regions are regularly arranged.

On the other hand, the mesh patterns of the conductor meshes of Samples 2 to 7 were produced by breaking the regularity of the reference pattern described above. The reference pattern was a mesh pattern of the conductor mesh of Sample 1. The branch points of the mesh pattern of each sample were determined by shifting the corresponding intersections of the reference patterns by independent shift amounts δ _rx and δ _ry (see FIG. 8) in the x-axis direction and the y-axis direction, respectively. The shift amount δ _rx in the x-axis direction is randomly determined according to a random number table by imposing a limit based on the arrangement pitch p _rx in the x-axis direction of the opening region corresponding to the length of one diagonal line of the opening region. The displacement amount δ _ry in the y-axis direction is determined randomly according to a random number table by imposing a limit based on the arrangement pitch p _ry in the y-axis direction of the opening region corresponding to the length of the other diagonal line of the opening region. did.

Specifically, in the mesh pattern of sample 2, “0 ≦ δ _rx ≦ 0.05 × p _rx ” and “0 ≦ δ _ry ≦ 0.05 × p _ry ” were set. In the mesh pattern of Sample 3, “0 ≦ δ _rx ≦ 0.1 × p _rx ” and “0 ≦ δ _ry ≦ 0.1 × p _ry ” were set. In the mesh pattern of sample 4, “0 ≦ δ _rx ≦ 0.2 × p _rx ” and “0 ≦ δ _ry ≦ 0.2 × p _ry ” were set. In the mesh pattern of Sample 5, “0 ≦ δ _rx ≦ 0.3 × p _rx ” and “0 ≦ δ _ry ≦ 0.3 × p _ry ” were set. In the mesh pattern of sample 6, “0 ≦ δ _rx ≦ 0.4 × p _rx ” and “0 ≦ δ _ry ≦ 0.4 × p _ry ” were set. In the mesh pattern of sample 7, “0 ≦ δ _rx ≦ 0.5 × p _rx ” and “0 ≦ δ _ry ≦ 0.5 × p _ry ” were set.

  Next, the connecting elements of the mesh pattern of each sample were extended linearly between two branch points corresponding to two intersections located at both ends of one line segment of the reference pattern. And the conductor mesh which concerns on samples 2-7 was produced with the mesh pattern determined as mentioned above.

As described above, the standard deviations σ _p1 and σ _p2 related to the mesh pattern and the standard deviations σ _ap1 and σ _ap2 related to the regular pattern related to each mesh pattern are obtained from the conductor meshes according to the samples 1 to 7 thus manufactured. The ratio (σ _p1 / σ _ap1 ) and the ratio (σ _p2 / σ _ap2 ) were calculated. The values of these ratios are shown in Table 1 along with whether or not the following conditions (a) and (b) are satisfied.
1.02 ≦ σ _p1 / σ _ap1 ≦ 1.16 (a)
1.02 ≦ σ _p2 / σ _ap2 ≦ 1.16 (b)

The conductor mesh according to each sample was placed on the display surface of a commercially available liquid crystal display device, and the presence or absence of moire and shading unevenness was confirmed. In the liquid crystal display device, similarly to the pixel arrangement shown in FIG. 19, the pixels are arranged at the same fixed pitch in both the x-axis direction and the y-axis direction. The presence or absence of moiré and shading unevenness was confirmed in a state in which the liquid crystal display device displayed the entire white color. The confirmation results are shown in Table 1. The column of evaluation in Table 1 shows the result of judgment based on the following criteria.
“X: Moire or shading unevenness was confirmed to be a problem in normal use.”
“O: Moire or shading unevenness was not confirmed to an extent that would cause problems in normal use.
"

  Note that various modifications can be made to the above-described embodiment. Hereinafter, an example of modification will be described with reference to the drawings as appropriate. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above embodiment are used for the parts that can be configured in the same manner as in the above embodiment. A duplicate description is omitted.

  In the touch panel sensor 25 shown in FIG. 2 of the above-described embodiment, each detection electrode 45 is formed as an elongated rectangular conductor mesh 46 disposed in the active area Aa1, but is not limited thereto. . The configuration of the detection electrode 45 can be variously changed. In the example shown in FIG. 20, each first detection electrode 45 a is connected to connect a plurality of conductor meshes 46 arranged at intervals in the longitudinal direction and two adjacent conductor meshes 46. Part 48. Each detection electrode 45 extends linearly in the active area Aa1 by the conductor mesh 46 and the connection portion 48. The width of the region where each detection electrode 45 is disposed is thicker in the portion where the conductor mesh 46 is provided. Each first detection electrode 45a included in the first electrode 40a intersects a number of second detection electrodes 45b included in the second electrode 40b. As shown in FIG. 20, the first detection electrode 45a of the first electrode 40a intersects the connection portion 48 of the second detection electrode 45b of the second electrode 40b at the connection portion 43 thereof. Therefore, the conductor mesh 46 of the first detection electrode 45a is disposed between two adjacent second detection electrodes 45b, and the conductor mesh 46 of the second detection electrode 45b is adjacent to the two first detection electrodes 45a. It is arranged between.

  In the modification shown in FIG. 20, the conductor mesh 46 of the first electrode 40 a and the conductor mesh 46 of the second electrode 40 b do not overlap in the normal direction of the touch panel sensor 25. Therefore, when the mesh pattern 50 of the conductor mesh 46 forming each of the electrodes 40a and 40b satisfies the above conditions (a) and (b) alone, both moire and shading unevenness can be effectively inconspicuous. It becomes possible.

  In the above-described embodiment, an example of the reference pattern 60 has been described. However, the present invention is not limited to the above-described example, and various patterns can be employed. For example, the reference pattern 60 may be formed as a honeycomb pattern. Further, as described above, the reference pattern 60 may include two or more types of opening regions 61, and the various opening regions 61 may be regularly arranged.

  In addition, although the some modification with respect to embodiment mentioned above was demonstrated above, naturally, it is also possible to apply combining several modifications suitably.

DESCRIPTION OF SYMBOLS 10 Display apparatus 12 Image display mechanism 13 Light-shielding part 13a Wide part 20 Touch panel apparatus 22 Transparent cover 25 Touch panel sensor 30 Position detection electrode substrate 30a First position detection electrode substrate 30b Second position detection electrode substrate 35 Base material sheet 40 Electrode 40a First 1 electrode 40b 2nd electrode 42 extraction electrode 42a 1st extraction electrode 42b 2nd extraction electrode 43 terminal part 45 detection electrode 45a 1st detection electrode 45b 2nd detection electrode 46 conductor mesh 48 connection part 50 mesh pattern 51 opening area 52 branch Point 53 Connection element 60 Reference pattern 61 Opening region 62 Intersection 63 Line segment 66 First parallel line group 66a First straight line 67 Second parallel line group 67a Second straight line 70 Regular pattern 76 First straight line group 76a First straight line 77 Second Straight line group 77a second straight line

Claims (17)

Comprising a detection electrode for forming a mesh pattern defining a plurality of opening regions;
In the integrated value distribution at each angle of the power spectrum of the mesh pattern obtained by applying Fourier transform and polar coordinate transformation to the scan data of the mesh pattern created by using a planar scanner, it is 0 ° or more and less than 180 °. The standard deviation σ _p1 of the power spectrum integrated value within the range of 60 ° (θ _p1 ± 30 [°]) centered on the first peak angle θ _p1 [°] at which the power spectrum integrated value becomes the largest within the range, and ,
In the power spectrum integrated value distribution of the mesh pattern, within the range of 60 ° centered on the second peak angle θ _p2 [°] at which the power spectrum integrated value becomes the second largest within the range of 0 ° to less than 180 °. The standard deviation σ _p2 of the power spectrum integrated value at (θ _p2 ± 30 [°]),
The first peak angle θ _p1 [°] and second peak angle θ _p2 [°] in the integrated value distribution of the power spectrum of the mesh pattern, and the mesh pattern at the first peak angle θ _p1 [°]. A first spatial frequency forming a first peak located on a higher frequency side than a fundamental frequency in the distribution of power spectrum at each spatial frequency, and the mesh pattern at the second peak angle θ _p2 [°]. The image data of the regular pattern determined based on the second spatial frequency forming the first peak located on the higher frequency side than the fundamental frequency in the distribution of the power spectrum at each spatial frequency, Fourier transform and In the integrated value distribution at each angle of the power spectrum of the regular pattern obtained by performing polar coordinate transformation The first peak angle theta _p1 standard deviation of the power spectrum integral value in [°] in the range of 60 ° around the (theta _p1 ± 30 [°]) sigma _ap1, and the second peak angle theta _p2 The standard deviation σ _ap2 of the power spectrum integrated value within a range of 60 ° centered on [°] (θ _p2 ± 30 [°]) satisfies the following condition,
1.02 ≦ σ _p1 / σ _ap1 ≦ 1.16
1.02 ≦ σ _p2 / σ _ap2 ≦ 1.16
The regular pattern has a coordinate system set in the same manner as when the power spectrum of the mesh pattern is specified from the scan data of the mesh pattern, and the first space has a first peak angle θ _p1 [°]. The first straight line groups arranged at a constant pitch having a length corresponding to the frequency, and arranged at a constant pitch having a length corresponding to the second spatial frequency in the direction of the second peak angle θ _p2 [°]. A touch panel sensor formed by the second straight line group.   2. The touch panel sensor according to claim 1, wherein in the integrated value distribution of the power spectrum of the mesh pattern, only two local maximum values of the power spectrum integrated value exist within a range of 0 ° to less than 180 °. The touch panel sensor according to claim 1, wherein 60 ° ≦ | θ _p1 −θ _p2 | ≦ 80 ° or 100 ° ≦ | θ _p1 −θ _p2 | ≦ 120 °.   The touch panel sensor according to claim 1, wherein the opening regions are arranged in two intersecting directions.   The touch panel sensor according to claim 1, wherein the opening region has a quadrangular shape. The mesh pattern includes conductive connecting elements extending between two branch points to define the open area;
Each branch point of the mesh pattern is formed on a plurality of line segments extending between two intersections to define an opening region, and is on one intersection of a reference pattern in which the opening regions are regularly arranged or a predetermined length. Less than or equal to the length of the one intersection point, and each connecting element of the mesh pattern has two intersection points respectively corresponding to two intersection points located at both ends of one line segment. The touch panel sensor according to any one of claims 1 to 5, wherein the touch panel sensor extends between the branch points.   The touch panel sensor according to claim 6, wherein the reference pattern is regularly arranged in two directions in which opening regions having a fixed shape intersect.   The touch panel sensor according to claim 6 or 7, wherein the reference pattern is regularly arranged in two directions in which certain rectangular opening regions intersect.   The scan data of the mesh pattern is obtained by converting the mesh pattern into image data as a two-dimensional image of a region in which the line width of the conductive wire forming the mesh pattern is configured by a plurality of pixels and is 3 cm × 3 cm or more of the mesh pattern The touch panel sensor according to any one of claims 1 to 8, wherein   The touch panel sensor according to any one of claims 1 to 9, wherein the scan data is binarized before being subjected to Fourier transform.   The touch panel sensor according to claim 10, wherein the binarized scan data is subjected to a thinning process before being subjected to Fourier transform.   The standard deviation regarding the integrated value distribution of the power spectrum of the mesh pattern is a value specified after blurring the integrated value distribution within an angle range of ± 10 ° using a Gaussian filter. The touch-panel sensor as described in any one of Claims 1-11 which exists.   The standard deviation related to the integrated value distribution of the power spectrum of the regular pattern is a specified value after blurring the integrated value distribution within an angle range of ± 10 ° using a Gaussian filter. The touch-panel sensor as described in any one of Claims 1-12 which exists. The detection electrode includes a first detection electrode and a second detection electrode arranged to overlap the first detection electrode;
The touch panel sensor according to claim 1, wherein the mesh pattern is formed by the first detection electrode. The detection electrode includes a first detection electrode and a second detection electrode arranged to overlap the first detection electrode;
The touch panel according to any one of claims 1 to 13, wherein a part of the mesh pattern is formed by the first detection electrode and the other part of the mesh pattern is formed by the second detection electrode. Sensor.   A touch panel device provided with the touch panel sensor as described in any one of Claims 1-15. The touch panel sensor according to any one of claims 1 to 16, and
An image display mechanism disposed to overlap the touch panel sensor.