Wiring substrate, image display device, and method for manufacturing wiring substrate

Abstract

A wiring substrate is provided with: a transparent substrate; and a mesh wiring layer disposed on the substrate. The grid wiring layer includes wirings. An opening portion is formed by being surrounded by the wiring. An isolated wiring electrically independent of the wiring is provided within the opening.

Description

Technical Field

[0001] Embodiments of this disclosure relate to wiring substrates, image display devices, and methods for manufacturing wiring substrates. Background Technology

[0002] Currently, portable terminal devices such as smartphones, tablets, and smart glasses (AR, MR, etc.) are constantly evolving towards higher functionality, miniaturization, thinner designs, and lighter weight. These portable terminal devices use multiple communication frequency bands. Therefore, multiple antennas corresponding to these communication frequency bands are required. For example, portable terminal devices may incorporate multiple antennas, including antennas for telephone communication, WiFi (Wireless Fidelity), 3G (Generation), 4G (Generation), 5G (Generation), LTE (Long Term Evolution), Bluetooth (trademark), and NFC (Near Field Communication). However, with the miniaturization of portable terminal devices, the space available for antenna installation is limited, thus narrowing the freedom of antenna design. Furthermore, because the antenna is housed within a limited space, the radio wave sensitivity may not meet the requirements.

[0003] Therefore, a thin-film antenna capable of being mounted on the display area of ​​portable terminal devices or the transmission area of ​​smart glasses has been developed. This thin-film antenna is a transparent antenna with an antenna pattern formed on a transparent substrate. The antenna pattern is formed from a grid-like conductive mesh layer. The conductive mesh layer includes opaque conductor portions that form the conductive layer and multiple openings that are non-forming portions.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2011-66610

[0007] Patent Document 2: Japanese Patent No. 5636735

[0008] Patent Document 3: Japanese Patent No. 5695947

[0009] However, for example, in conventional thin-film antennas, one or more conductive mesh layers are formed on a transparent substrate. In this case, it is required that the conductive mesh layers be difficult to visually identify.

[0010] One of the objectives of this embodiment is to provide a wiring substrate, an image display device, and a method for manufacturing a wiring substrate that makes the mesh wiring layer difficult to be visually identified. Summary of the Invention

[0011] The embodiments of this disclosure relate to the following [1] to

[16] . [1]

[0013] A wiring substrate comprising: A transparent substrate; and A mesh wiring layer disposed on the substrate, The mesh wiring layer contains wiring. An opening is formed by being surrounded by the wiring. An isolated wiring, independent of the electrical wiring, is provided inside the opening. [2]

[0015] According to the wiring substrate described in [1], wherein, The area ratio of the isolated wiring within the opening is 0.1% or more and 0.3% or less. [3]

[0017] According to the wiring substrate described in [1] or [2], wherein, The distance between the wiring and the isolated wiring is greater than 4.0 μm and less than 400 μm. [4]

[0019] The wiring substrate according to any one of [1] to [3], wherein, The spacing of the isolated wiring is less than 500μm. [5]

[0021] The wiring substrate according to any one of [1] to [4], wherein, The line width of the isolated wiring is less than 3.0 μm. [6]

[0023] The wiring substrate according to any one of [1] to [5], wherein, The length of the isolated wiring is less than 50 μm. [7]

[0025] The wiring substrate according to any one of [1] to [6], wherein, The isolated wirings are separated from each other by gaps, the length of which is more than 4.0 μm and less than 400 μm. [8]

[0027] The wiring substrate according to any one of [1] to [7], wherein, The spacing of the wiring is greater than 500μm and less than 10mm. [9]

[0029] The wiring substrate according to any one of [1] to [8], wherein, The wiring width is less than 3.0 μm.

[10]

[0031] The wiring substrate according to any one of [1] to [9], wherein, The aperture ratio of the mesh wiring layer is greater than 98% and less than 100%.

[11]

[0033] The wiring substrate according to any one of [1] to

[10] , wherein, At least one of the wiring and the isolated wiring is configured irregularly.

[12]

[0035] The wiring substrate according to any one of [1] to

[11] , wherein, A dummy wiring layer, electrically independent of the mesh wiring layer, is provided around the mesh wiring layer.

[13]

[0037] According to the wiring substrate described in

[12] , wherein, Multiple dummy routing layers are provided, and the aperture ratio of the mesh routing layer and the dummy routing layer increases in stages from the mesh routing layer toward the dummy routing layer away from the mesh routing layer.

[14]

[0039] The wiring substrate according to any one of [1] to

[13] , wherein, The wiring substrate has radio wave transceiver function.

[15]

[0041] An image display device comprising:

[14] the wiring substrate described thereon; and The display device is stacked on the wiring substrate.

[16]

[0043] A method for manufacturing a wiring substrate, comprising: The process of preparing a transparent substrate; and The process of forming a mesh wiring layer on the substrate, The mesh wiring layer contains wiring. An opening is formed by being surrounded by the wiring. An isolated wiring, independent of the electrical wiring, is provided inside the opening.

[0044] According to embodiments of this disclosure, the mesh wiring layer can be made difficult to visually identify. Attached Figure Description

[0045] Figure 1 This is a top view illustrating one embodiment of an image display device.

[0046] Figure 2 This is a cross-sectional view illustrating one embodiment of an image display device. Figure 1 (Sectional view along line II-II).

[0047] Figure 3 This is a top view showing a wiring substrate according to one embodiment.

[0048] Figure 4 This is an enlarged top view showing one embodiment of the wiring substrate.

[0049] Figure 5 This is a cross-sectional view of a wiring substrate illustrating one embodiment. Figure 4 (VV-line sectional view).

[0050] Figure 6 This is a cross-sectional view of a wiring substrate illustrating one embodiment. Figure 4 (VI-VI line sectional view).

[0051] Figure 7 This is a cross-sectional view showing a module of one implementation.

[0052] Figure 8A This is a cross-sectional view illustrating a method for manufacturing a wiring substrate according to one embodiment.

[0053] Figure 8B This is a cross-sectional view illustrating a method for manufacturing a wiring substrate according to one embodiment.

[0054] Figure 8C This is a cross-sectional view illustrating a method for manufacturing a wiring substrate according to one embodiment.

[0055] Figure 8D This is a cross-sectional view illustrating a method for manufacturing a wiring substrate according to one embodiment.

[0056] Figure 8E This is a cross-sectional view illustrating a method for manufacturing a wiring substrate according to one embodiment.

[0057] Figure 8F This is a cross-sectional view illustrating a method for manufacturing a wiring substrate according to one embodiment.

[0058] Figure 9A This is a cross-sectional view showing a method of manufacturing a module according to one embodiment.

[0059] Figure 9B This is a cross-sectional view showing a method of manufacturing a module according to one embodiment.

[0060] Figure 9C This is a cross-sectional view showing a method of manufacturing a module according to one embodiment.

[0061] Figure 10A This is a cross-sectional view illustrating a method for manufacturing an image display device according to one embodiment.

[0062] Figure 10B This is a cross-sectional view illustrating a method for manufacturing an image display device according to one embodiment.

[0063] Figure 10C This is a cross-sectional view illustrating a method for manufacturing an image display device according to one embodiment.

[0064] Figure 10D This is a cross-sectional view illustrating a method for manufacturing an image display device according to one embodiment.

[0065] Figure 11 This is an enlarged top view of the wiring substrate of the image display device showing the first modified example.

[0066] Figure 12 This is an enlarged top view of the wiring substrate of the image display device showing the second modified example.

[0067] Figure 13 This is a top view of the wiring substrate of the image display device, showing a third modified example.

[0068] Figure 14 This is an enlarged top view of the wiring substrate of the image display device showing the third modified example.

[0069] Figure 15 This is a top view of the wiring substrate of the image display device, showing a fourth modified example.

[0070] Figure 16 This is an enlarged top view of the wiring substrate of the image display device showing the fourth modified example.

[0071] Figure 17 This is an enlarged top view of the wiring substrate of the image display device showing the fifth modified example. Detailed Implementation

[0072] First, through Figures 1 to 10D One implementation method will be described. Figures 1 to 10D This is a diagram illustrating this embodiment.

[0073] The figures shown below are schematic illustrations. Therefore, the size and shape of each part have been appropriately exaggerated for ease of understanding. Furthermore, modifications can be made appropriately without departing from the technical concept. In addition, in the figures shown below, the same reference numerals are used for the same parts, and sometimes detailed descriptions are omitted. Furthermore, the dimensions and material names of the components described in this specification are examples of embodiments and are not limiting; appropriate selections can be made. In this specification, terms describing shape or geometric conditions, such as parallel, orthogonal, and perpendicular, are interpreted in addition to their strict meaning, encompassing substantially the same state.

[0074] Furthermore, in the following embodiments, "X direction" refers to a direction parallel to one side of the image display device. "Y direction" is a direction perpendicular to the X direction and parallel to the other side of the image display device. "Z direction" refers to a direction perpendicular to both the X and Y directions and parallel to the thickness direction of the image display device. Additionally, "front side" refers to the surface on the positive side in the Z direction, which is the light-emitting surface side of the image display device, the side facing the observer. "Back side" refers to the surface on the negative side in the Z direction, the side opposite to the light-emitting surface and the side facing the observer of the image display device. Furthermore, in this embodiment, the mesh wiring layer 20 is described as having radio wave transceiver function (functioning as an antenna), but the mesh wiring layer 20 may also not have radio wave transceiver function (functioning as an antenna).

[0075] Reference Figure 1 and Figure 2 The structure of the image display device of this embodiment will be described.

[0076] like Figure 1 and Figure 2 As shown, the image display device 60 of this embodiment includes an image display device laminate 70 and a display device 61 laminated on the image display device laminate 70. Figure 2 As shown, the image display device laminate 70 includes a wiring substrate 10, a first transparent adhesive layer 95, and a second transparent adhesive layer 96. Additionally, the image display device laminate 70 includes a cover glass 75 and a decorative layer 74. The cover glass 75 and the decorative layer 74 are disposed on the wiring substrate 10 with the first transparent adhesive layer 95 as a barrier. Furthermore, an impact-absorbing layer (not shown) may be disposed between the first transparent adhesive layer 95 and the cover glass 75. Furthermore, module 80A is constituted by the wiring substrate 10 and a power supply line 85 electrically connected to the wiring substrate 10.

[0077] The wiring substrate 10 of module 80A includes a substrate 11, a mesh wiring layer 20, and a power supply section 40. For example... Figure 2As shown, the substrate 11 includes a first surface 11a and a second surface 11b located on the opposite side of the first surface 11a. A mesh wiring layer 20 is disposed on the first surface 11a of the substrate 11. In addition, the power supply unit 40 is electrically connected to the mesh wiring layer 20.

[0078] like Figure 2 As shown, the image display device 60 has a light-emitting surface 64. The wiring substrate 10 described above is located on the side of the light-emitting surface 64 (positive side in the Z direction) relative to the display device 61. A communication module 63 is disposed on the opposite side of the light-emitting surface 64 (negative side in the Z direction) relative to the display device 61. The image display device laminate 70, the display device 61, and the communication module 63 are housed within a housing 62.

[0079] exist Figure 1 and Figure 2 The image display device 60 shown can transmit and receive radio waves at a predetermined frequency (e.g., a frequency greater than 1 GHz) via the communication module 63, enabling communication. The communication module 63 may include any of the following: a millimeter-wave antenna, a telephone antenna, a WiFi antenna, a 3G antenna, a 4G antenna, a 5G antenna, an LTE antenna, a Bluetooth antenna, an NFC antenna, etc. Examples of such an image display device 60 include portable terminal devices such as smartphones and tablets.

[0080] The display device 61 is, for example, an organic EL (Electro Luminescence) display device. The display device 61 can also be configured to be easily deformable. For example, the rigidity of the display device 61 can be lower than that of the cover glass 75. The display device 61 may also include, for example, a metal layer (not shown), a support substrate, a resin substrate, a thin-film transistor (TFT), and an organic EL layer. A touch sensor (not shown) may also be disposed on the display device 61. Furthermore, the display device 61 is not limited to an organic EL display device. For example, the display device 61 may be other display devices with its own light-emitting function, or it may be a micro-LED display device including micro-LED elements (light emitters). Additionally, the display device 61 may also be a liquid crystal display device including liquid crystal.

[0081] Next, the image display device laminate 70 will be described in detail. As described above, the image display device laminate 70 includes a wiring substrate 10, a first transparent adhesive layer 95, and a second transparent adhesive layer 96. Additionally, as described above, the image display device laminate 70 includes a cover glass 75 and a decorative layer 74. It should be noted that the image display device laminate 70 can also be assembled onto a head-mounted display (smart glasses) by mounting it onto a frame (not shown).

[0082] The cover glass 75 of the image display device laminate 70 is located on the first surface 11a side of the substrate 11 of the wiring substrate 10. A first transparent adhesive layer 95 is located between the substrate 11 of the wiring substrate 10 and the cover glass 75. A decorative layer 74 is located between the cover glass 75 and the first transparent adhesive layer 95. A second transparent adhesive layer 96 is located on the second surface 11b side of the substrate 11 of the wiring substrate 10. Here, the first transparent adhesive layer 95 of the image display device laminate 70 will be described first. Further details regarding the wiring substrate 10 will be described later.

[0083] The first transparent adhesive layer 95 is an adhesive layer that directly or indirectly bonds the wiring substrate 10 to the decorative layer 74 and the cover glass 75. This first transparent adhesive layer 95 is located on the first surface 11a side of the substrate 11. The first transparent adhesive layer 95 has optical transparency and may also be an OCA (Optical Clear Adhesive) layer. An OCA layer is, for example, manufactured as follows: First, a liquid curable adhesive layer composition containing a polymeric compound is coated onto a release film such as polyethylene terephthalate (PET). Then, it is cured using, for example, ultraviolet light (UV), thereby obtaining an OCA sheet. After the OCA sheet is adhered to an object, the release film is peeled off, thereby obtaining the aforementioned OCA layer. The material of the first transparent adhesive layer 95 may also be an acrylic resin, a silicone resin, or a polyurethane resin. In particular, the first transparent adhesive layer 95 may contain an acrylic resin. In this case, the second transparent adhesive layer 96 preferably contains an acrylic resin. Therefore, the difference in refractive index between the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be substantially eliminated, and the reflection of visible light at the interface B3 between the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be suppressed more reliably.

[0084] Regarding the first transparent adhesive layer 95, the transmittance of visible light can be 85% or more, preferably 90% or more. It should be noted that there is no particular upper limit to the transmittance of visible light of the first transparent adhesive layer 95; for example, it can be 100% or less. By setting the transmittance of visible light of the first transparent adhesive layer 95 to the above range, the transparency of the laminate 70 for the image display device can be improved, making it easier to visually identify the display device 61 of the image display device 60. Furthermore, visible light refers to light with a wavelength of 400 nm or more and 700 nm or less. Additionally, a transmittance of 85% or more of visible light means that when measuring the absorbance of the component to be measured (e.g., the first transparent adhesive layer 95), the transmittance is 85% or more across the entire wavelength range of 400 nm or more and 700 nm or less. The absorbance measurement can be performed using a spectrophotometer (spectrometer V-670 manufactured by Nippon Spectrophotometer Co., Ltd.).

[0085] As described above, the wiring substrate 10 is disposed on the light-emitting surface 64 side relative to the display device 61. In this case, the wiring substrate 10 is located between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. More specifically, a portion of the substrate 11 of the wiring substrate 10 is disposed in a portion of the area between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. In this case, the first transparent adhesive layer 95, the second transparent adhesive layer 96, the display device 61, and the cover glass 75 each have an area larger than the substrate 11 of the wiring substrate 10. Thus, by disposing the substrate 11 of the wiring substrate 10 in a portion of the image display device 60 rather than the entire surface when viewed from above, the area of ​​the wiring substrate 10 can be reduced. Therefore, when manufacturing the first direction wiring 21 and the second direction wiring 22 of the wiring substrate 10 (described later), multiple sheets of the first direction wiring 21 and the second direction wiring 22 can be manufactured at once. Therefore, the manufacturing cost of each wiring substrate 10 can be reduced. Alternatively, the substrate 11 of the wiring substrate 10 can be disposed in the entire surface of the image display device 60 when viewed from above. In this case, the positioning time required can be shortened when the wiring board 10 is placed on the display device 61.

[0086] As described above, the wiring substrate 10 includes: a transparent substrate 11; and a grid wiring layer 20 disposed on a first surface 11a of the substrate 11. A power supply unit 40 is electrically connected to the grid wiring layer 20. The power supply unit 40 is electrically connected to the communication module 63 via a power supply line 85. Furthermore, a portion of the wiring substrate 10 is not disposed between the first transparent adhesive layer 95 and the second transparent adhesive layer 96, but protrudes outward (to the negative side in the Y direction) from between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. Specifically, the area in the wiring substrate 10 where the power supply unit 40 is disposed protrudes outward. This allows for easy electrical connection between the power supply unit 40 and the communication module 63. On the other hand, the area in the wiring substrate 10 where the grid wiring layer 20 is disposed is located between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. Furthermore, although not shown, the grid wiring layer 20 may also be disposed on the second surface 11b of the substrate 11. That is, the grid wiring layer 20 may also be disposed at a position closer to the display device 61 than the substrate 11. Details about this wiring substrate 10 will be described later.

[0087] The second transparent adhesive layer 96 is an adhesive layer that directly or indirectly bonds the display device 61 to the wiring substrate 10. This second transparent adhesive layer 96 is located on the second surface 11b side of the substrate 11. The second transparent adhesive layer 96, like the first transparent adhesive layer 95, has optical transparency and can also be an OCA (Optical Clear Adhesive) layer. The material of the second transparent adhesive layer 96 can also be acrylic resin, silicone resin, or polyurethane resin, etc. In particular, the second transparent adhesive layer 96 can also contain acrylic resin. Therefore, the difference in refractive index between the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be substantially eliminated, thereby more reliably suppressing the reflection of visible light at the interface B3 between the first transparent adhesive layer 95 and the second transparent adhesive layer 96.

[0088] Regarding the second transparent adhesive layer 96, the transmittance of visible light (light with a wavelength of 400 nm or more and 700 nm or less) can be 85% or more, preferably 90% or more. It should be noted that there is no particular upper limit to the transmittance of visible light of the second transparent adhesive layer 96; for example, it can be 100% or less. By setting the transmittance of visible light of the second transparent adhesive layer 96 to the above range, the transparency of the laminate 70 for the image display device can be improved, making it easier to visually identify the display device 61 of the image display device 60.

[0089] In such an image display device 60, the difference between the refractive index of the substrate 11 and the refractive index of the first transparent adhesive layer 95 is 0.05 or less, preferably 0.02 or less. Furthermore, the difference between the refractive index of the substrate 11 and the refractive index of the second transparent adhesive layer 96 is 0.05 or less, preferably 0.02 or less. Moreover, the difference between the refractive index of the first transparent adhesive layer 95 and the refractive index of the second transparent adhesive layer 96 is preferably 0.05 or less, more preferably 0.02 or less. For example, when the materials of the first transparent adhesive layer 95 and the second transparent adhesive layer 96 are acrylic resins with a refractive index of 1.49, the refractive index of the substrate 11 is set to 1.45 or more and 1.54 or less. Examples of such materials include fluoropolymers, silicone resins, polyolefin resins, polyester resins, acrylic resins, polycarbonate resins, polyimide resins, and cellulose resins.

[0090] By suppressing the difference between the refractive index of the substrate 11 and the refractive index of the first transparent adhesive layer 95 to below 0.05, the reflection of visible light at the interface B1 between the substrate 11 and the first transparent adhesive layer 95 can be suppressed, making the substrate 11 difficult to distinguish with the naked eye. Furthermore, by suppressing the difference between the refractive index of the substrate 11 and the refractive index of the second transparent adhesive layer 96 to below 0.05, the reflection of visible light at the interface B2 between the substrate 11 and the second transparent adhesive layer 96 can be suppressed, making the substrate 11 difficult to distinguish with the naked eye. Moreover, by suppressing the difference between the refractive index of the first transparent adhesive layer 95 and the second transparent adhesive layer 96 to below 0.05, the reflection of visible light at the interface B3 between the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be suppressed. Therefore, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be made difficult to distinguish with the naked eye.

[0091] In particular, the materials of the first transparent adhesive layer 95 and the second transparent adhesive layer 96 are preferably the same. This further reduces the difference in refractive index between the first transparent adhesive layer 95 and the second transparent adhesive layer 96, and suppresses the reflection of visible light at the interface B3 between the first transparent adhesive layer 95 and the second transparent adhesive layer 96.

[0092] In addition, Figure 2 In this embodiment, the thickness of at least one of the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 can be at least 1.5 times the thickness T1 of the substrate 11, preferably at least 2 times, and more preferably at least 2.5 times. Thus, by making the thickness T3 of the first transparent adhesive layer 95 or the thickness T4 of the second transparent adhesive layer 96 sufficiently thick relative to the thickness T1 of the substrate 11, the first transparent adhesive layer 95 or the second transparent adhesive layer 96 deforms in the thickness direction in the region overlapping with the substrate 11, absorbing the thickness of the substrate 11. This suppresses the formation of a step difference on the first transparent adhesive layer 95 or the second transparent adhesive layer 96 at the periphery of the substrate 11, making it difficult for an observer to detect the presence of the substrate 11.

[0093] The thickness of at least one of the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 is preferably 10 times or less than the thickness T1 of the substrate 11, more preferably 5 times or less. Therefore, the thickness T3 of the first transparent adhesive layer 95 or the thickness T4 of the second transparent adhesive layer 96 will not become excessively thick, and the overall thickness of the image display device 60 can be reduced.

[0094] In addition, Figure 2In this configuration, the thickness T3 of the first transparent adhesive layer 95 can also be thicker than the thickness T4 of the second transparent adhesive layer 96. Here, as described above, the first transparent adhesive layer 95 is located on the first surface 11a of the substrate 11 of the wiring substrate 10. Furthermore, a mesh wiring layer 20 is disposed on the first surface 11a of the substrate 11 of the wiring substrate 10. Therefore, due to the unevenness formed by the mesh wiring layer 20, it is possible for unevenness to form on the surface of the first transparent adhesive layer 95. In contrast, by making the thickness T3 of the first transparent adhesive layer 95 thicker than the thickness T4 of the second transparent adhesive layer 96, it is possible to suppress the formation of unevenness on the surface of the first transparent adhesive layer 95, and to make the surface of the first transparent adhesive layer 95 smooth.

[0095] The difference between the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 is preferably 100 μm or less. Here, as described above, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be OCA layers. Therefore, due to residual stress that may be generated in the OCA layer during fabrication, tensile stresses that cause the first transparent adhesive layer 95 and the second transparent adhesive layer 96 to shrink may occur in them. These tensile stresses may increase as the thickness T3 of the first transparent adhesive layer 95 or the thickness T4 of the second transparent adhesive layer 96 increases. Furthermore, if the difference between the tensile stress generated in the first transparent adhesive layer 95 and the tensile stress generated in the second transparent adhesive layer 96 increases, the wiring substrate 10 may warp. In contrast, by making the difference between the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 less than 100 μm, the difference between the tensile stress generated in the first transparent adhesive layer 95 and the tensile stress generated in the second transparent adhesive layer 96 can be reduced. This reduces the warping of the wiring substrate 10 caused by the difference between the tensile stress generated in the first transparent adhesive layer 95 and the tensile stress generated in the second transparent adhesive layer 96.

[0096] exist Figure 2In this configuration, the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 can be the same. In this case, the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 can each be at least 1.5 times, preferably at least 2.0 times, the thickness T1 of the substrate 11. That is, the total thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 (T3+T4) is at least 3 times the thickness T1 of the substrate 11. Thus, by making the total thickness T3 and T4 of the first transparent adhesive layer 95 and the second transparent adhesive layer 96 sufficiently thick relative to the thickness T1 of the substrate 11, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 deform (shrink) in the thickness direction in the region overlapping with the substrate 11. Therefore, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 absorb the thickness of the substrate 11. Therefore, it is possible to suppress the generation of step difference on the first transparent adhesive layer 95 or the second transparent adhesive layer 96 at the periphery of the substrate 11, making it difficult for an observer to detect the presence of the substrate 11.

[0097] When the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 are the same, the thickness T3 of the first transparent adhesive layer 95 and the thickness T4 of the second transparent adhesive layer 96 can be less than 5 times the thickness T1 of the substrate 11, preferably less than 3 times. Therefore, the thicknesses T3 and T4 of both the first transparent adhesive layer 95 and the second transparent adhesive layer 96 will not become excessively thick, and the overall thickness of the image display device 60 can be reduced.

[0098] Specifically, the thickness T1 of the substrate 11 can be, for example, 2.0 μm or more, or 10 μm or more, preferably 15 μm or more. By setting the thickness T1 of the substrate 11 to 2.0 μm or more, the strength of the wiring substrate 10 can be maintained, making it difficult for the first direction wiring 21 and the second direction wiring 22 of the mesh wiring layer 20 (described later) to deform. Alternatively, the thickness T1 of the substrate 11 can be, for example, 200 μm or less, or 50 μm or less, preferably 25 μm or less. By setting the thickness T1 of the substrate 11 to 200 μm or less, step differences on the first transparent adhesive layer 95 and the second transparent adhesive layer 96 at the periphery of the substrate 11 can be suppressed, making it difficult for an observer to detect the presence of the substrate 11. Furthermore, by setting the thickness T1 of the substrate 11 to 50 μm or less, step differences on the first transparent adhesive layer 95 and the second transparent adhesive layer 96 at the periphery of the substrate 11 can be further suppressed, making it even more difficult for an observer to detect the presence of the substrate 11.

[0099] The thickness T3 of the first transparent adhesive layer 95 can be, for example, 15 μm or more, preferably 20 μm or more. The thickness T3 of the first transparent adhesive layer 95 can be, for example, 500 μm or less, preferably 300 μm or less, and more preferably 250 μm or less. By making the thickness T3 of the first transparent adhesive layer 95 500 μm or less, the thickness T3 of the first transparent adhesive layer 95 will not become excessively thick, and the overall thickness of the image display device 60 can be reduced. Furthermore, by making the thickness T3 of the first transparent adhesive layer 95 300 μm or less, the overall thickness of the image display device 60 can be further reduced.

[0100] The thickness T4 of the second transparent adhesive layer 96 can be, for example, 15 μm or more, preferably 20 μm or more. The thickness T4 of the second transparent adhesive layer 96 can be, for example, 500 μm or less, preferably 300 μm or less, and more preferably 250 μm or less. By making the thickness T4 of the second transparent adhesive layer 96 500 μm or less, the thickness T4 of the second transparent adhesive layer 96 will not become excessively thick, and the overall thickness of the image display device 60 can be reduced. Furthermore, by making the thickness T4 of the second transparent adhesive layer 96 300 μm or less, the overall thickness of the image display device 60 can be made even thinner.

[0101] As described above, the image display device laminate 70 is constituted by a wiring substrate 10, a first transparent adhesive layer 95 having an area larger than the substrate 11 of the wiring substrate 10, and a second transparent adhesive layer 96 having an area larger than the substrate 11. In this embodiment, such an image display device laminate 70 is also provided.

[0102] Refer again Figure 2 The cover glass 75 is disposed directly or indirectly on the first transparent adhesive layer 95. The cover glass 75 is located on the Z-direction positive side of the first transparent adhesive layer 95 and is disposed on the decorative layer 74. The cover glass 75 is a glass component that allows light to pass through. The cover glass 75 is plate-shaped, and its shape can also be rectangular when viewed from above. The thickness of the cover glass 75 can be, for example, 200 μm or more and 1000 μm or less, preferably 300 μm or more and 700 μm or less. The length of the cover glass 75 in the long side direction (Y direction) can be, for example, 20 mm or more and 500 mm or less, preferably 100 mm or more and 200 mm or less. The length of the cover glass 75 in the short side direction (X direction) can be 20 mm or more and 500 mm or less, preferably 50 mm or more and 100 mm or less.

[0103] At least a portion of the decorative layer 74 is disposed on the first transparent adhesive layer 95. The decorative layer 74 may also be a decorative film. For example, when viewed from the observer's side, all or part of the opening of the portion of the decorative layer 74 that overlaps with the display area of ​​the display device 61 blocks light from the portion outside the display area. That is, the decorative layer 74 is disposed in such a way that it covers the end of the display device 61 when viewed from the observer's side.

[0104] like Figure 1 As shown, the image display device 60 is generally rectangular in shape when viewed from above, with its long side parallel to the Y-direction and its short side parallel to the X-direction. The length L4 of the image display device 60 in the long side direction (Y-direction) is selected, for example, within the range of 20 mm to 500 mm, preferably within the range of 100 mm to 200 mm. The length L5 of the image display device 60 in the short side direction (X-direction) is selected, for example, within the range of 20 mm to 500 mm, preferably within the range of 50 mm to 100 mm. Alternatively, the planar shape of the image display device 60 can also be a rectangle with rounded corners.

[0105] Next, refer to Figures 3 to 6 The structure of the wiring substrate will be explained. Figures 3 to 6 This is a diagram showing the wiring substrate of this embodiment.

[0106] The wiring substrate 10 in this embodiment is used in the image display device 60 described above (see reference 60). Figure 1 and Figure 2 The wiring substrate 10 can be disposed between the first transparent adhesive layer 95 and the second transparent adhesive layer 96 at a position closer to the light-emitting surface 64 than the display device 61 (see reference). Figure 2 ).like Figure 3 As shown above, such a wiring substrate 10 has: a transparent substrate 11; and a grid wiring layer 20 disposed on the substrate 11. Additionally, the power supply unit 40 is electrically connected to the grid wiring layer 20.

[0107] The substrate 11 is approximately rectangular in shape when viewed from above. In the illustrated example, its long side is parallel to the X-direction, and its short side is parallel to the Y-direction. The substrate 11 is transparent and approximately flat, with a generally uniform thickness. The length L1 of the substrate 11 in the long side direction (Y-direction) of the image display device 60 (see reference) Figure 1 and Figure 3 For example, it can be selected within the range of 10mm to 200mm. The length L2 of the substrate 11 in the short side direction (X direction) of the image display device 60 (refer to...) Figure 1For example, it can be selected within the range of 3mm to 100mm. In addition, the planar shape of the substrate 11 can also be a rectangle with rounded corners.

[0108] The material of substrate 11 can be any material that is transparent in the visible light region and electrically insulating. For example, organic insulating materials such as polyester resins, acrylic resins, polycarbonate resins, polyimide resins, polyolefin resins, cellulose resins, or fluoropolymers are preferred as the material of substrate 11. Polyester resins can also be polyethylene terephthalate, etc. Acrylic resins can also be polymethyl methacrylate, etc. Polyolefin resins can be cyclic olefin polymers, etc. Cellulose resins can be triacetyl cellulose, etc. Fluoropolymers can also be PTFE or PFA, etc. For example, organic insulating materials such as cyclic olefin polymers (e.g., ZF-16 manufactured by ZEON Corporation of Japan) or polynorbornene polymers (manufactured by Sumitomo Bakelite Co., Ltd.) can also be used as the material of substrate 11. Alternatively, glass or ceramics can be appropriately selected as the material of substrate 11 depending on the application. Furthermore, while an example of substrate 11 consisting of a single layer is illustrated, it is not limited to this, and a structure with multiple substrates or layers stacked may also be used. Alternatively, the substrate 11 can be a film-shaped component or a plate-shaped component.

[0109] The dielectric loss tangent of the substrate 11 is preferably 0.002 or less. By making the dielectric loss tangent of the substrate 11 within the above range, especially when the electromagnetic waves (e.g., millimeter waves) transmitted and received by the mesh wiring layer 20 are high frequency, the gain loss (reduction in sensitivity) associated with the transmission and reception of electromagnetic waves can be reduced.

[0110] The relative permittivity of substrate 11 is preferably 2 or higher and 10 or lower. By setting the relative permittivity of substrate 11 to 2 or higher, the options for the material of substrate 11 can be increased. Furthermore, by setting the relative permittivity of substrate 11 to 10 or lower, the gain loss associated with the transmission and reception of electromagnetic waves can be reduced. That is, when the relative permittivity of substrate 11 increases, the impact of substrate 11 thickness on the propagation of electromagnetic waves becomes greater. Additionally, if the propagation of electromagnetic waves is adversely affected, the dielectric loss tangent of substrate 11 increases, and the gain loss associated with the transmission and reception of electromagnetic waves may increase. In contrast, by setting the relative permittivity of substrate 11 to 10 or lower, the impact of substrate 11 thickness on the propagation of electromagnetic waves can be reduced. Therefore, the gain loss associated with the transmission and reception of electromagnetic waves can be reduced. This is particularly effective when the electromagnetic waves (e.g., millimeter waves) transmitted and received by the mesh wiring layer 20 are high-frequency.

[0111] The dielectric loss tangent and relative permittivity of substrate 11 can be measured according to IEC 62562. Specifically, firstly, a test piece is prepared by cutting out the portion of substrate 11 before the formation of the mesh wiring layer 20. The dimensions of the test piece are: a width of 10 mm or more and 20 mm or less, and a length of 50 mm or more and 100 mm or less. Next, the dielectric loss tangent or relative permittivity is measured according to IEC 62562.

[0112] In this embodiment, the substrate 11 is transparent. In this specification, "transparent" means that the transmittance of visible light (light with a wavelength of 400 nm or more and 700 nm or less) is 85% or more. The transmittance of visible light of the substrate 11 can be 85% or more, preferably 90% or more. Furthermore, there is no particular limitation on the upper limit of the transmittance of visible light of the substrate 11; for example, it can be 100% or less. By setting the transmittance of visible light of the substrate 11 to the above range, the transparency of the wiring substrate 10 can be improved, making it easier to visually identify the display device 61 of the image display device 60.

[0113] In this embodiment, the mesh wiring layer 20 is composed of an antenna pattern that functions as an antenna. This mesh wiring layer 20 can also be configured as an array antenna. Thus, when the mesh wiring layer 20 is configured as an array antenna, the performance of millimeter-wave antennas with high transmit and receive straight-line characteristics can be improved. Furthermore, an array antenna refers to an antenna with multiple antenna elements (radiating elements) arranged regularly, and is an antenna in which the amplitude and phase of the excitation of the elements can be controlled independently.

[0114] like Figure 3 As shown, multiple mesh wiring layers 20 are formed on the substrate 11. Preferably, four or more mesh wiring layers 20 are provided. In the illustrated example, four mesh wiring layers 20 are formed on the substrate 11 (see reference). Figure 1 Additionally, such as Figure 3 As shown, the mesh wiring layer 20 may not exist on the entire surface of the substrate 11, but only in a portion of the substrate 11. Each mesh wiring layer 20 may also have the same shape as each other. In this case, regarding each mesh wiring layer 20, it is preferable that the length (Y-direction distance) L of the end-side portion 20b (described later) is... a Error and width (distance in the X direction) W a The errors are all within 10%. Therefore, the performance of millimeter-wave antennas can be effectively improved.

[0115] The mesh cabling layer 20 has a base-side portion (transmission section) 20a on the power supply section 40 side and an end-side portion (transceiver section) 20b connected to the base-side portion 20a. The base-side portion 20a is connected to the power supply section 40. In this case, the base-side portion (transmission section) 20a can also be configured as a microstrip line or a coplanar line. The shapes of the base-side portion 20a and the end-side portion 20b are approximately rectangular when viewed from above. In this case, the length (Y-direction distance) of the end-side portion 20b is approximately the same as the length (Y-direction distance) of the base-side portion 20a, and the width (X-direction distance) of the end-side portion 20b is wider than the width (X-direction distance) of the base-side portion 20a.

[0116] The end portion 20b of the mesh wiring layer 20 corresponds to a specified frequency band. That is, the length (distance in the Y direction) L of the end portion 20b... a This becomes the length corresponding to a specific frequency band. Furthermore, the lower the corresponding frequency band, the longer the length L of the 20b portion at the end. a The longer the mesh wiring layer 20, the better. Besides corresponding to millimeter-wave antennas, it can also correspond to any of the following: telephone antennas, WiFi antennas, 3G antennas, 4G antennas, 5G antennas, LTE antennas, Bluetooth antennas, NFC antennas, etc. Furthermore, the lengths of the multiple end portions 20b can differ to correspond to different frequency bands. Alternatively, if the wiring substrate 10 does not have radio wave transceiver functionality, each mesh wiring layer 20 can also function as a hover function, fingerprint authentication, heater, noise cutoff (shielding), etc. Moreover, the hover function refers to the ability to operate the display even without direct user contact.

[0117] In the illustrated example, the long side of the end portion 20b is parallel to the X direction, and its short side is parallel to the Y direction. Alternatively, the end portion 20b may also have its long side parallel to the Y direction and its short side parallel to the X direction. The length L of the end portion 20b in the Y direction is... a For example, it can be selected within a range of 1mm to 100mm. The width W of the end-side portion 20b in the X direction... a For example, it can be selected within a range of 1mm to 100mm. Especially in the case where the mesh wiring layer 20 is a millimeter-wave antenna, the length L of the end portion 20b... a The length L can be selected within a range of 1 mm or more, more preferably 1.5 mm or more. In the case where the mesh wiring layer 20 is a millimeter-wave antenna, the length L of the end portion 20b... a It can be selected within a range of 10mm or less, more preferably 5mm or less.

[0118] The distance between the mesh wiring layers 20 is preferably 0.2 mm or more and 5 mm or less. That is, the distance D between the end side portions 20b is... 20b (refer to Figure 3 The preferred diameter is 0.2 mm or more and 5 mm or less. This is achieved by adjusting the distance D between the end portions 20b. 20b With a distance of 0.2 mm or more, accidental interference of electromagnetic waves between antenna elements can be suppressed. This is achieved by adjusting the distance D between the end portions 20b. 20b With a diameter of 5 mm or less, the overall size of the array antenna formed by the mesh wiring layer 20 can be reduced. For example, in the case of a 28 GHz millimeter-wave antenna with the mesh wiring layer 20, the distance D between the end portions 20b can be reduced. 20b It can also be 3.5mm. Furthermore, in the case of a 60GHz millimeter-wave antenna with mesh wiring layer 20, the distance D between the end portions 20b is... 20b It can also be 1.6mm.

[0119] like Figure 4 As shown, the mesh wiring layer 20 has a pattern shape in which the metal wires are arranged in a grid or mesh pattern. This pattern shape is repeated in the X and Y directions. That is, the mesh wiring layer 20 has a pattern shape composed of a portion extending in a first direction (e.g., the Y direction) (first direction wiring 21 described later) and a portion extending in a second direction (e.g., the X direction) (second direction wiring 22 described later).

[0120] The mesh wiring layer 20 has a plurality of wirings. Specifically, the mesh wiring layer 20 has a plurality of first-direction wirings (wirings) 21 and a plurality of second-direction wirings (wirings) 22 connecting the plurality of first-direction wirings 21. The plurality of first-direction wirings 21 and the plurality of second-direction wirings 22 are arranged prominently on the substrate 11. The plurality of first-direction wirings 21 and the plurality of second-direction wirings 22 are integrally formed into a grid-like or mesh-like shape. Each first-direction wiring 21 extends in the long side direction (Y direction) of the mesh wiring layer 20. Each second-direction wiring extends in a straight line in the width direction (X direction) of the mesh wiring layer 20. In addition, the first-direction wirings 21 and the second-direction wirings 22 may also extend in directions that are not parallel to either the X or Y direction.

[0121] In the mesh wiring layer 20, openings 23 are formed by being surrounded by wiring. That is, in the mesh wiring layer 20, multiple openings 23 are formed by being surrounded by adjacent first-direction wiring 21 and adjacent second-direction wiring 22. The transparent substrate 11 is exposed from each opening 23. As a result, the overall transparency of the wiring substrate 10 can be improved.

[0122] Each opening 23 has a roughly square planar shape when viewed from above. That is, the first-direction wiring 21 and the second-direction wiring 22 are arranged at equal intervals. The spacing P1 between the multiple first-direction wirings 21 can be, for example, 0.01 mm or more and 10 mm or less, or 500 μm or more and 10 mm or less. Similarly, the spacing P2 between the multiple second-direction wirings 22 can be, for example, 0.01 mm or more and 10 mm or less, or 500 μm or more and 10 mm or less. By arranging the multiple first-direction wirings 21 and the multiple second-direction wirings 22 at equal intervals, the size of the openings 23 within the mesh wiring layer 20 is consistent, making the mesh wiring layer 20 less visually discernible. Furthermore, the spacing P1 of the first-direction wirings 21 is equal to the spacing P2 of the second-direction wirings 22. Therefore, as described above, each opening 23 is roughly square when viewed from above, and the transparent substrate 11 is exposed from each opening 23. Therefore, by increasing the area of ​​each opening 23, the overall transparency of the wiring substrate 10 can be improved. Furthermore, the length L3 of one side of each opening 23 can be, for example, in the range of 0.01 mm or more and 10 mm or less, or in the range of 500 μm or more and 10 mm or less. In addition, each first-direction wiring 21 and each second-direction wiring 22 is orthogonal to each other, but is not limited to this; they can also intersect each other at acute or obtuse angles. Furthermore, the shape of the opening 23 is preferably the same shape and size throughout the entire surface, but it can also be varied depending on the location, resulting in unevenness throughout the entire surface.

[0123] like Figure 5 As shown, each first-direction wiring 21 has a cross-section perpendicular to its long side (X-direction cross-section) that is approximately rectangular or approximately square. In this case, the cross-sectional shape of the first-direction wiring 21 is approximately uniform along the long side direction (Y-direction) of the first-direction wiring 21. Figure 6 As shown, the cross-section (Y-direction cross-section) perpendicular to its long side direction of each second-direction wiring 22 is approximately rectangular or approximately square, having a shape approximately the same as the cross-section (X-direction cross-section) shape of the first-direction wiring 21 described above. In this case, the cross-sectional shape of the second-direction wiring 22 is approximately uniform along the long side direction (X-direction) of the second-direction wiring 22. The cross-sectional shapes of the first-direction wiring 21 and the second-direction wiring 22 do not necessarily have to be approximately rectangular or approximately square. For example, the cross-sectional shapes of the first-direction wiring 21 and the second-direction wiring 22 may also be approximately trapezoidal with the front side (positive Z-direction side) narrower than the back side (negative Z-direction side), or shapes with curved sides on both sides of the long side direction.

[0124] In this embodiment, the line width W1 of the first direction wiring 21 (refer to...) Figure 5 ) and the line width W2 of the second direction wiring 22 (refer to Figure 6 There are no particular limitations, and the appropriate width can be selected according to the application. Here, the linewidth W1 of the first direction wiring 21 is the width (X-direction distance) in the cross-section perpendicular to its long side direction, and the linewidth W2 of the second direction wiring 22 is the width (Y-direction distance) in the cross-section perpendicular to its long side direction. For example, the linewidth W1 of the first direction wiring 21 can be selected in the range of 0.1 μm or more and 5.0 μm or less, preferably 3.0 μm or less, and more preferably 0.2 μm or more and 2.0 μm or less. Similarly, the linewidth W2 of the second direction wiring 22 can be selected in the range of 0.1 μm or more and 5.0 μm or less, preferably 3.0 μm or less, and more preferably 0.2 μm or more and 2.0 μm or less.

[0125] The height H1 of the first direction wiring 21 (refer to) Figure 5 ) and the height H2 of the second direction wiring 22 (refer to Figure 6 There are no particular limitations, and the appropriate height can be selected according to the application. Here, the height H1 of the first direction wiring 21 and the height H2 of the second direction wiring 22 are the lengths in the Z direction. The height H1 of the first direction wiring 21 and the height H2 of the second direction wiring 22 can be selected, for example, in the range of 0.1 μm or more, preferably 0.2 μm or more. The height H1 of the first direction wiring 21 and the height H2 of the second direction wiring 22 can be selected, for example, in the range of 5.0 μm or less, preferably 2.0 μm or less.

[0126] The materials for the first-direction wiring 21 and the second-direction wiring 22 can be any conductive metallic material. In this embodiment, the material for the first-direction wiring 21 and the second-direction wiring 22 is copper, but it is not limited to this. For example, the materials for the first-direction wiring 21 and the second-direction wiring 22 can be metallic materials such as gold, silver, copper, platinum, tin, aluminum, iron, or nickel, or alloys containing these metals. Alternatively, the first-direction wiring 21 and the second-direction wiring 22 can also be plating layers formed by electroplating.

[0127] The overall aperture ratio At of the mesh wiring layer 20 can be, for example, in the range of 87% or more and less than 100%. By setting the overall aperture ratio At of the mesh wiring layer 20 to this range, the conductivity and transparency of the wiring substrate 10 can be ensured. The overall aperture ratio At of the mesh wiring layer 20 is preferably 95% or more and less than 100%, more preferably 98% or more and less than 100%. Thus, the conductivity of the wiring substrate 10 can be ensured while improving the transparency of the wiring substrate 10. Furthermore, the aperture ratio refers to the percentage (%) of the area of ​​the open region to the unit area of ​​a specified area (e.g., the entire area of ​​the mesh wiring layer 20). The open region refers to the area where the substrate 11 is exposed due to the absence of metal portions such as the first direction wiring 21 and the second direction wiring 22.

[0128] Here, a first isolated wire (isolated wire) 35 and a second isolated wire (isolated wire) 36, electrically independent of the first direction wiring (wiring) 21 and the second direction wiring (wiring) 22, are provided within the opening 23. In this embodiment, multiple first isolated wires 35 and second isolated wires 36 are provided within the opening 23. The first isolated wires 35 and second isolated wires 36 are electrically independent of the mesh wiring layer 20 (first direction wiring 21 and second direction wiring 22).

[0129] In this case, the first isolated wiring 35 extends parallel to the first directional wiring 21. Additionally, the second isolated wiring 36 extends parallel to the second directional wiring 22. Thus, by making the first isolated wiring 35 and the second isolated wiring 36 extend parallel to either the first directional wiring 21 or the second directional wiring 22, the mesh wiring layer 20 disposed on the substrate 11 becomes more difficult to see.

[0130] As described above, the first isolated wiring 35 and the second isolated wiring 36 are electrically independent from the first directional wiring 21 and the second directional wiring 22, respectively. The distance L between the first directional wiring 21 and the second isolated wiring 36 is... 11 Preferably, the diameter is 4.0 μm or larger and 400 μm or smaller. Additionally, the distance L between the second-direction wiring 22 and the first isolated wiring 35... 12 Preferably, the diameter is 4.0 μm or larger and 400 μm or smaller. This is achieved by making the distance L... 11 (distance L) 12 With a spacing of 4.0 μm or more, electrical connection between the first-direction wiring 21 (second-direction wiring 22) and the second isolated wiring 36 (first isolated wiring 35) can be effectively suppressed. Furthermore, by making the distance L... 11 (distance L) 12 With a distance of less than 400 μm, the first-direction wiring 21 (second-direction wiring 22) can be made inconspicuous. In other words, by making the distance L... 11 (distance L) 12With a mesh size of 400 μm or less, the first direction wiring 21 (second direction wiring 22) becomes unclear. As a result, the mesh wiring layer 20 is difficult to see on the surface of the image display device 60, and is difficult for the user of the image display device 60 to visually identify with the naked eye.

[0131] The first isolated wires 35 are separated from each other via a notch 37. In this case, the length L of the first isolated wires 35 is... 13 Preferably, the diameter is 5.0 μm or larger and 50 μm or smaller. Additionally, the length L of the notch 37... 14 Preferably, the diameter is 4.0 μm or larger and 400 μm or smaller. Furthermore, the second isolated wirings 36 are separated from each other via notches 38. In this case, the length L of the second isolated wirings 36... 15 Preferably, the diameter is 5.0 μm or larger and 50 μm or smaller. Additionally, the length L of the notch 37... 16 Preferably, it is 4.0 μm or more and 400 μm or less. This is achieved by making the length L of the first isolated wiring 35... 13 (Length L of the second isolated wiring 36) 15 With a diameter of 5.0 μm or more, the first-direction wiring 21 (second-direction wiring 22) becomes inconspicuous, making the mesh wiring layer 20 difficult for the user of the image display device 60 to visually identify. Furthermore, by making the length L of the first isolated wiring 35... 13 (Length L of the second isolated wiring 36) 15 With a notch length of 50 μm or less, the overall aperture ratio At of the mesh wiring layer 20 can be suppressed, thereby improving the transparency of the wiring substrate 10. This is achieved by making the notch 37 length L... 14 (Length L of the gap 38) 16 With a notch length of 4.0 μm or more, the overall aperture ratio At of the mesh wiring layer 20 can be increased, thereby improving the transparency of the wiring substrate 10. Furthermore, by increasing the length L of the notch 37... 14 (Length L of the gap 38) 16 With a thickness of 400μm or less, the first direction wiring 21 (second direction wiring 22) is inconspicuous, and the mesh wiring layer 20 is difficult for the user of the image display device 60 to visually identify.

[0132] Multiple first isolated wirings 35 are arranged at equal intervals along the X direction within the opening 23, with a spacing P between them. 11 For example, it can be in the range of 50μm or more and 500μm or less. Furthermore, multiple second isolated wirings 36 are arranged at equal intervals along the Y direction within the opening 23, with a spacing P between them. 12 For example, it can also be a range of 50 μm or more and 500 μm or less. This is achieved by adjusting the spacing P... 11 (spacing P) 12With a spacing of 50 μm or more, the overall aperture ratio At of the mesh wiring layer 20 can be increased, thereby improving the transparency of the wiring substrate 10. Furthermore, by increasing the spacing P... 11 (spacing P) 12 With a spacing of 500 μm or less, the first-direction wiring 21 (second-direction wiring 22) becomes inconspicuous, making the mesh wiring layer 20 difficult for the user of the image display device 60 to visually identify. Furthermore, by arranging the plurality of first isolated wirings 35 and the plurality of second isolated wirings 36 at equal intervals as in this embodiment, the first isolated wirings 35 and the second isolated wirings 36 become difficult to visually identify. Additionally, the transparent substrate 11 is exposed between the first isolated wirings 35 and the second isolated wirings 36. Therefore, the overall transparency of the wiring substrate 10 can be improved. Furthermore, within the opening 23, the spacing P of the first isolated wirings 35... 11 The spacing P between the second isolated wiring 36 and the second isolated wiring 36 12 They can be equal or different. In addition, each of the first isolated wirings 35 and each of the second isolated wirings 36 are orthogonal to each other, but not limited to this, they can also intersect each other at acute or obtuse angles.

[0133] like Figure 5 As shown, each first isolated wiring 35 has a cross-section perpendicular to its long side (X-direction cross-section) that is approximately rectangular or approximately square. In this case, the cross-sectional shape of the first isolated wiring 35 is approximately uniform along the long side direction (Y-direction) of the first isolated wiring 35. Figure 6 As shown, the cross-section (Y-direction cross-section) perpendicular to its long side direction of each second isolated wiring 36 is approximately rectangular or approximately square, having a shape approximately the same as the cross-section (X-direction cross-section) shape of the first isolated wiring 35 described above. In this case, the cross-sectional shape of the second isolated wiring 36 is approximately uniform along the long side direction (X-direction) of the second isolated wiring 36. The cross-sectional shapes of the first isolated wiring 35 and the second isolated wiring 36 do not necessarily have to be approximately rectangular or approximately square. For example, the cross-sectional shapes of the first isolated wiring 35 and the second isolated wiring 36 may also be approximately trapezoidal with the front side (positive Z-direction side) narrower than the back side (negative Z-direction side), or shapes with curved sides on both sides in the width direction.

[0134] In this embodiment, the line width W of the first isolated wiring 35 11 (refer to Figure 5 ) and the line width W of the second isolated wiring 36 12 (refer to Figure 6 There are no particular limitations; the appropriate width (W) can be selected based on the application. The first isolated wiring has a line width of 35. 11 and the line width W of the second isolated wiring 36 12Preferably, the line width W1 of the first direction wiring 21 and the line width W2 of the second direction wiring 22 are equal. Here, the line width W of the first isolated wiring 35 is... 11 It is the width (X-direction distance) in the cross section perpendicular to its long side, the linewidth W of the second isolated wiring 36. 12 It is the width (distance in the Y direction) in the cross section perpendicular to its long side. The linewidth W of the first isolated wiring 35. 11 For example, the line width can be selected within the range of 0.1 μm or more and 5.0 μm or less, preferably 3.0 μm or less, and more preferably 0.2 μm or more and 2.0 μm or less. Additionally, the line width W of the second isolated wiring 36... 12 For example, the linewidth can be selected within the range of 0.1 μm to 5.0 μm, preferably 3.0 μm or less, and more preferably 0.2 μm to 2.0 μm or less. By making the linewidth W... 11 (line width W) 12 With a line width of 0.2μm or greater, the first-direction wiring 21 (second-direction wiring 22) becomes inconspicuous, making the mesh wiring layer 20 difficult for the user of the image display device 60 to visually identify. This is achieved by making the line width W... 11 (line width W) 12 With a diameter of less than 3.0 μm, the aperture ratio At of the mesh wiring layer 20 can be increased, and the transparency of the wiring substrate 10 can be improved.

[0135] The first isolated wiring has a height of 35 H. 11 (refer to Figure 5 ) and the height H of the second isolated wiring 36 12 (refer to Figure 6 There are no particular limitations; the appropriate height (H) can be selected based on the application. Here, the height H of the first isolated wiring is 35. 11 and the height H of the second isolated wiring 36 12 These represent the lengths along the Z direction. The height H of the first isolated wiring is 35. 11 and the height H of the second isolated wiring 36 12 For example, the diameter can be selected within a range of 0.1 μm or larger, preferably 0.2 μm or larger. The height H of the first isolated wiring 35 11 and the height H of the second isolated wiring 36 12 For example, the range can be selected from below 5.0 μm, preferably below 2.0 μm.

[0136] The materials of the first isolated wiring 35 and the second isolated wiring 36 can also be the same as those of the first directional wiring 21 and the second directional wiring 22 described above. That is, the materials of the first isolated wiring 35 and the second isolated wiring 36 can be any conductive metallic material. In this embodiment, the material of the first isolated wiring 35 and the second isolated wiring 36 is copper, but it is not limited to this. The materials of the first isolated wiring 35 and the second isolated wiring 36 can be, for example, metallic materials such as gold, silver, copper, platinum, tin, aluminum, iron, or nickel, or alloys containing these metals. In addition, the first isolated wiring 35 and the second isolated wiring 36 can also be plating layers formed by electroplating.

[0137] The area ratio of the first isolated wiring 35 and the second isolated wiring 36 within the opening 23 is preferably 0.1% or more and 0.3% or less. By making the area ratio 0.1% or more, the first direction wiring 21 (second direction wiring 22) becomes less conspicuous, making the mesh wiring layer 20 difficult for the user of the image display device 60 to visually identify. Furthermore, by making the area ratio 0.3% or less, the overall aperture ratio At of the mesh wiring layer 20 can be increased, thereby improving the transparency of the wiring substrate 10. In addition, the area ratio refers to the percentage (%) of the area of ​​the first isolated wiring 35 and the second isolated wiring 36 to the area of ​​the opening 23.

[0138] It should be noted that, although not shown in the figure, a protective layer can also be formed on the first surface 11a of the substrate 11 in a manner that covers the mesh wiring layer 20. The protective layer protects the mesh wiring layer 20 and is formed in a manner that covers at least the mesh wiring layer 20 in the substrate 11. As a material for the protective layer, colorless and transparent insulating resins such as copolymers of acrylic resins and modified resins such as poly(methyl methacrylate) and poly(ethyl methacrylate), polyester, polyvinyl alcohol, polyvinyl acetate, polyvinyl alcohol acetal, polyvinyl butyral, polyurethane, epoxy resin, polyamide, and chlorinated polyolefin can be used.

[0139] Refer again Figure 3 The power supply unit 40 is electrically connected to the mesh wiring layer 20. The power supply unit 40 is composed of a generally rectangular, conductive, thin plate-like component. The long side of the power supply unit 40 is parallel to the X-direction, and the short side is parallel to the Y-direction.

[0140] In addition, the power supply section 40 is disposed at the long side end (negative side end in the Y direction) of the substrate 11. The material of the power supply section 40 can be, for example, metals such as gold, silver, copper, platinum, tin, aluminum, iron or nickel, or alloys containing these metals.

[0141] The power supply unit 40 is assembled on the wiring board 10 onto the image display device 60 (see reference). Figure 1 and Figure 2 The power supply unit 40 is electrically connected to the communication module 63 of the image display device 60 via the power supply line 85. Furthermore, the power supply unit 40 is disposed on the substrate 11, but is not limited thereto; part or all of the power supply unit 40 may be located outside the periphery of the substrate 11. Alternatively, the power supply unit 40 may be flexibly formed, thereby wrapping around to the side or back of the image display device 60. In this case, the power supply unit 40 may also be electrically connected to the communication module 63 on the side or back of the image display device 60.

[0142] On the positive side of the Y direction, the mesh wiring layer 20 is electrically connected to the power supply unit 40. In this case, the power supply unit 40 and the mesh wiring layer 20 are formed as one unit. The thickness T5 of the power supply unit 40 (distance in the Z direction, referring to...) Figure 6 ) can be connected to the height H1 of the first direction wiring 21 (refer to Figure 5 ) and the height H2 of the second direction wiring 22 (refer to Figure 6 The same applies, for example, it can be selected within a range of above 0.1μm and below 5.0μm.

[0143] Next, refer to Figure 7 The structure of the module is explained. Figure 7 This is a diagram illustrating the modules of this embodiment.

[0144] like Figure 7 As shown, module 80A includes the wiring substrate 10 described above and a power supply line 85 electrically connected to the power supply unit 40 via an anisotropic conductive film 85c. As described above, when module 80A is assembled into image display device 60, the power supply unit 40 of wiring substrate 10 is electrically connected to communication module 63 of image display device 60 via power supply line 85.

[0145] The power supply line 85 is pressed onto the wiring substrate 10 via an anisotropic conductive film (ACF) 85c. The anisotropic conductive film 85c comprises resin materials such as acrylic resin and epoxy resin, and conductive particles 85d. In the illustrated example, the anisotropic conductive film 85c covers a portion of the power supply section 40. This helps to suppress corrosion and other damage to the power supply section 40.

[0146] The anisotropic conductive film 85c is disposed opposite to the power supply section 40. Furthermore, a portion of the conductive particles 85d is in contact with the power supply section 40. Thus, the power supply line 85 is electrically connected to the power supply section 40. Additionally, a portion of the anisotropic conductive film 85c may be dissolved around the power supply line 85 when the power supply line 85 is pressed onto the wiring substrate 10. Furthermore, the particle size of the conductive particles 85d can be, for example, approximately 7.0 μm.

[0147] The power supply line 85 can also be a flexible printed circuit board, for example. The power supply line 85 has a substrate 85a and a metal wiring portion 85b stacked on the substrate 85a. The substrate 85a can contain, for example, a resin material such as polyimide or a liquid crystal polymer. The metal wiring portion 85b can also contain, for example, copper. The metal wiring portion 85b is electrically connected to the power supply portion 40 via conductive particles 85d.

[0148] [Manufacturing methods for wiring substrates, modules, and laminates for image display devices]

[0149] Next, refer to Figures 8A to 8F , Figures 9A to 9C as well as Figures 10A to 10D The manufacturing methods of the wiring board 10, the module 80A, and the image display device 60 of this embodiment will be described. Figures 8A to 8F This is a cross-sectional view showing the manufacturing method of the wiring substrate 10 of this embodiment. Figures 9A to 9C This is a cross-sectional view showing the manufacturing method of module 80A in this embodiment. Figures 10A to 10D This is a cross-sectional view showing the manufacturing method of the image display device 60 of this embodiment.

[0150] First, refer to Figures 8A to 8F The manufacturing method of the wiring substrate of this embodiment will be described.

[0151] First, such as Figure 8A As shown, a substrate 11 is prepared, comprising a first surface 11a and a second surface 11b located on the opposite side of the first surface 11a. The substrate 11 is transparent.

[0152] Next, a grid wiring layer 20 and a power supply section 40 electrically connected to the grid wiring layer 20 are formed on the first surface 11a of the substrate 11.

[0153] At this point, firstly, as Figure 8B As shown, a metal foil 51 is laminated over approximately the entire area of ​​the first surface 11a of the substrate 11. In this embodiment, the thickness of the metal foil 51 can be 0.1 μm or more and 5.0 μm or less. In this embodiment, the metal foil 51 may also contain copper.

[0154] Next, as Figure 8C As shown, a photocurable insulating resist 52 is supplied to approximately the entire surface area of ​​the metal foil 51. Examples of such photocurable insulating resist 52 include organic resins such as acrylic resins and epoxy resins.

[0155] Next, as Figure 8DAs shown, the insulating layer 54 is formed by photolithography. In this case, the photocurable insulating resist 52 is patterned by photolithography to form the insulating layer 54 (resist pattern). At this time, the insulating layer 54 is formed such that the metal foil 51 corresponding to the first direction wiring 21, the second direction wiring 22, the first isolated wiring 35, and the second isolated wiring 36 is covered by the insulating layer 54.

[0156] Next, as Figure 8E As shown, the metal foil 51 on the first surface 11a of the substrate 11, located in the portion not covered by the insulating layer 54, is removed. At this time, the metal foil 51 is etched by performing a wet treatment using strong acids such as ferric chloride, copper chloride, sulfuric acid / hydrochloric acid, persulfate, hydrogen peroxide or aqueous solutions thereof, or combinations thereof, to expose the first surface 11a of the substrate 11.

[0157] Next, as Figure 8F As shown, the insulating layer 54 is removed. In this case, the insulating layer 54 on the metal foil 51 is removed by performing a wet treatment using a permanganate solution or N-methyl-2-pyrrolidone, an acid or alkali solution, or a dry treatment using oxygen plasma.

[0158] Thus, a wiring substrate 10 is obtained having a substrate 11 and a mesh wiring layer 20 disposed on a first surface 11a of the substrate 11. In this case, the mesh wiring layer 20 includes a first-direction wiring 21 and a second-direction wiring 22. In addition, an opening 23 is formed by being surrounded by the first-direction wiring 21 and the second-direction wiring 22. Moreover, a first isolated wiring 35 and a second isolated wiring 36, which are electrically independent of the first-direction wiring 21 and the second-direction wiring 22, are provided in the opening 23. At this time, the power supply section 40 may also be formed from a portion of a metal foil. Alternatively, a flat plate-shaped power supply section 40 may be prepared separately and electrically connected to the mesh wiring layer 20.

[0159] Next, refer to Figures 9A to 9C The manufacturing method of the module in this embodiment will be described.

[0160] First, such as Figure 9A As shown, a wiring substrate 10 is prepared. At this time, for example, by... Figures 8A to 8F The wiring substrate 10 is fabricated using the method shown.

[0161] Next, the power supply line 85 is electrically connected to the power supply unit 40 via an anisotropic conductive film 85c containing conductive particles 85d. At this time, firstly, as... Figure 9B As shown, an anisotropic conductive film 85c and a power supply line 85 are disposed on the wiring substrate 10. At this time, the anisotropic conductive film 85c is disposed between the power supply line 85 and the power supply section 40.

[0162] Next, as Figure 9C As shown, the power supply line 85 is pressed onto the wiring substrate 10. At this time, pressure and heat are applied to the power supply line 85, thereby pressing it onto the wiring substrate 10. Furthermore, a portion of the conductive particles 85d comes into contact with the power supply section 40. Thus, the power supply line 85 is electrically connected to the power supply section 40. At this time, a portion of the anisotropic conductive film 85c can dissolve into the area surrounding the power supply line 85.

[0163] Thus, a module 80A is obtained, which includes a wiring substrate 10 and a power supply line 85 electrically connected to the power supply unit 40 via an anisotropic conductive film 85c containing conductive particles 85d.

[0164] Next, refer to Figures 10A to 10D The manufacturing method of the image display device 60 of this embodiment will be described.

[0165] At this point, firstly, as Figure 10A As shown, for example, the cover glass 75 and the decorative layer 74 are laminated with the first transparent adhesive layer 95. At this time, the first transparent adhesive layer 95 can be a liquid curable adhesive layer composition containing a polymeric compound. This curable adhesive layer composition may also contain monomers containing polar groups. When laminating the cover glass 75 and the decorative layer 74 with the first transparent adhesive layer 95, for example, the first transparent adhesive layer 95 may be heated to approximately 60°C.

[0166] Next, as Figure 10B As shown, the wiring substrate 10 of module 80A is stacked on the first transparent adhesive layer 95.

[0167] Next, as Figure 10C As shown, a second transparent adhesive layer 96 is laminated on the wiring substrate 10. At this time, a liquid curable adhesive layer composition containing a polymeric compound can be used as the second transparent adhesive layer 96. This curable adhesive layer composition may also contain monomers containing polar groups. Thus, by laminating the second transparent adhesive layer 96 on the wiring substrate 10, the wiring substrate 10 is sandwiched between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. In this way, a laminate 70 for an image display device comprising the first transparent adhesive layer 95, the second transparent adhesive layer 96, and the wiring substrate 10 can be obtained. When laminating the second transparent adhesive layer 96 on the wiring substrate 10, for example, the first transparent adhesive layer 95, etc., can be heated such that the first transparent adhesive layer 95 and the second transparent adhesive layer 96 are at approximately 60°C.

[0168] Next, as Figure 10DAs shown, the display device 61 is stacked on the second transparent adhesive layer 96. At this time, for example, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 can be heated to about 60°C.

[0169] Next, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 are cured, for example, by using ultraviolet light (UV).

[0170] Thus, an image display device 60 is obtained, which includes an image display device laminate 70 and a display device 61 laminated on the image display device laminate 70.

[0171] [The function of this implementation method]

[0172] Next, the function of this embodiment, which is constructed in this way, will be described.

[0173] like Figure 1 and Figure 2 As shown, the wiring substrate 10 is assembled onto the image display device 60, which has a display device 61. At this time, the wiring substrate 10 is disposed on the display device 61. The grid wiring layer 20 of the wiring substrate 10 is electrically connected to the communication module 63 of the image display device 60 via a power supply unit 40 and a power supply line 85. Thus, radio waves of a predetermined frequency can be transmitted and received via the grid wiring layer 20, enabling communication using the image display device 60.

[0174] According to this embodiment, the mesh wiring layer 20 includes a first-direction wiring 21 and a second-direction wiring 22. Furthermore, an opening 23 is formed by surrounding the first-direction wiring 21 and the second-direction wiring 22. Moreover, a first isolated wiring 35 and a second isolated wiring 36, electrically independent of the first-direction wiring 21 and the second-direction wiring 22, are disposed within the opening 23. Therefore, the first-direction wiring 21 and the second-direction wiring 22 are inconspicuous, making the mesh wiring layer 20 difficult for the user of the image display device 60 to visually identify.

[0175] In this case, in the wiring substrate 10, to improve the transmittance of visible light, it is necessary to increase the spacing P1 of the first-direction wiring 21 (the spacing P2 of the second-direction wiring 22). On the other hand, increasing the spacing P1 of the first-direction wiring 21 may cause the first-direction wiring 21 to become conspicuous. In contrast, by providing the first isolated wiring 35 and the second isolated wiring 36 within the opening 23, the first-direction wiring 21 can be made inconspicuous even when the spacing P1 of the first-direction wiring 21 is increased. Therefore, even when the spacing P1 of the first-direction wiring 21 is increased, the mesh wiring layer 20 can be made difficult for the user of the image display device 60 to visually identify with the naked eye. In other words, in the wiring substrate 10, it is possible to improve the transmittance of visible light while making the mesh wiring layer 20 difficult for the user of the image display device 60 to visually identify with the naked eye.

[0176] Furthermore, according to this embodiment, the wiring substrate 10 includes a transparent substrate 11 and a grid wiring layer 20 disposed on the substrate 11. The grid wiring layer 20 has a grid-like pattern formed by opaque conductor portions that serve as conductive layers and multiple openings. Therefore, the transparency of the wiring substrate 10 is ensured. Consequently, when the wiring substrate 10 is disposed on the display device 61, the display device 61 can be visually identified through the openings 23 of the grid wiring layer 20, without obstructing the visual visibility of the display device 61.

[0177] Next, a modified example of the wiring substrate will be described.

[0178] Figure 11 A first modified example of a wiring substrate is shown. Figure 11 The difference in the variant shown is that the planar shape of each opening 23 is approximately a regular hexagon when viewed from above; the other structures are the same as described above. Figures 1 to 10D The shapes shown are roughly the same. Figure 11 In the middle, to and Figures 1 to 10D Parts with the same shape are labeled with the same number and detailed descriptions are omitted.

[0179] exist Figure 11 In the wiring substrate 10 shown, the planar shape of each opening 23 is approximately hexagonal when viewed from above. In this modified example, the mesh wiring layer 20 includes wiring 25. That is, the opening 23 is formed by being surrounded by wiring 25. Furthermore, the line width and height of the wiring 25, as well as the material constituting the wiring 25, can be the same as the wiring 21 in the first direction.

[0180] In this variation, an isolated wire 39a, electrically independent of the wire 25, is provided within the opening 23. This isolated wire 39a extends within the opening 23 in three directions, forming a regular hexagon when viewed from above, with its ends connected to each other. Furthermore, the isolated wires 39a are separated from each other via notches 39b. Additionally, the length and spacing of the isolated wires 39a, as well as the material constituting the isolated wires 39a, can be the same as the first isolated wire 35. Furthermore, the length of the notch 39b can be the same as the notch 37.

[0181] According to this modified example, an isolated wiring 39a, electrically independent of the wiring 25, is provided inside the opening 23. As a result, the wiring 25 can be made inconspicuous, and the grid wiring layer 20 can be made difficult for the user of the image display device 60 to visually identify.

[0182] Figure 12 A second modified example of the wiring substrate is shown. Figure 12 The difference in the variant shown is that the planar shapes of each opening 23 are different, while the other structures are the same as those described above. Figures 1 to 11 The shapes shown are roughly the same. Figure 12 In the middle, to and Figures 1 to 11 Parts with the same shape are labeled with the same number and detailed descriptions are omitted.

[0183] exist Figure 12 In the wiring substrate 10 shown, the planar shapes of each opening 23 are different. Specifically, the planar shapes of each opening 23 are dissimilar hexagons when viewed from above. In this case, the wiring 25 is irregularly arranged. In addition, in this modified example, isolated wiring 39a is irregularly arranged within the opening 23. Specifically, the isolated wiring 39a extends along a predetermined direction within the opening 23 in such a way that the shape formed by connecting the ends to each other is a dissimilar hexagon when viewed from above.

[0184] In this variation, the planar shapes of each opening 23 are different. This suppresses the occurrence of light rays (stripes of light observed as trailing patterns) that might occur when the wiring 25 is arranged periodically. Furthermore, although not shown, it is also possible to arrange the wiring 25 regularly and the isolated wiring 39a irregularly. Alternatively, although not shown, it is also possible to arrange the wiring 25 irregularly and the isolated wiring 39a regularly.

[0185] Figure 13 and Figure 14 A third modified example of the wiring substrate is shown. Figure 13 and Figure 14 The difference in the variant shown is that a dummy wiring layer 30 is provided around the mesh wiring layer 20, while the other structures are the same as described above. Figures 1 to 12The shapes shown are roughly the same. Figure 13 and Figure 14 In the middle, to and Figures 1 to 12 Parts with the same shape are labeled with the same number and detailed descriptions are omitted.

[0186] exist Figure 13 In the wiring substrate 10 shown, a dummy wiring layer 30 is provided around the grid wiring layer 20. This dummy wiring layer 30 is different from the grid wiring layer 20 and does not actually function as an antenna.

[0187] like Figure 14 As shown, the dummy wiring layer 30 is composed of repeated dummy wirings 30a with a predetermined pattern shape. That is, the dummy wiring layer 30 includes a plurality of dummy wirings 30a, each of which is electrically independent from the grid wiring layer 20 (first direction wiring 21 and second direction wiring 22). Furthermore, the plurality of dummy wirings 30a are regularly arranged throughout the entire area of ​​the dummy wiring layer 30. The plurality of dummy wirings 30a are separated from each other in the planar direction and are arranged protrudingly on the substrate 11. That is, each dummy wiring 30a is electrically independent from the grid wiring layer 20, the first isolated wiring 35, the second isolated wiring 36, the power supply section 40, and other dummy wirings 30a. The shape of each dummy wiring 30a is approximately L-shaped when viewed from above.

[0188] In this case, the dummy wiring 30a has a shape formed by a partial absence of the pattern shape of the aforementioned mesh wiring layer 20. Therefore, the difference between the mesh wiring layer 20 and the dummy wiring layer 30 is difficult to visually identify, and the mesh wiring layer 20 disposed on the substrate 11 is difficult to see. Figure 14 As shown, the dummy wiring 30a extends parallel to either the first-direction wiring 21 or the second-direction wiring 22. Specifically, the dummy wiring 30a includes a first portion 31a extending parallel to the first-direction wiring 21 and a second portion 32a extending parallel to the second-direction wiring 22. Thus, by making the dummy wiring 30a extend parallel to either the first-direction wiring 21 or the second-direction wiring 22, the mesh wiring layer 20 disposed on the substrate 11 becomes more difficult to see. The aperture ratio of the dummy wiring layer 30 may be the same as or different from that of the mesh wiring layer 20, but it is preferably close to the aperture ratio of the mesh wiring layer 20.

[0189] By providing a dummy wiring layer 30, electrically independent of the mesh wiring layer 20, around the mesh wiring layer 20 as in this modified example, the outer edge of the mesh wiring layer 20 can be made unclear. Therefore, the mesh wiring layer 20 can be made difficult to see on the surface of the image display device 60, and can be made difficult for the user of the image display device 60 to visually identify with the naked eye.

[0190] Figure 15 and Figure 16 A fourth modified example of the wiring substrate is shown. Figure 15 and Figure 16 The difference in the variant shown is that multiple dummy wiring layers 30A and 30B with different aperture ratios are provided around the mesh wiring layer 20; the other structures are the same as described above. Figures 1 to 14 The shapes shown are roughly the same. Figure 15 and Figure 16 In the middle, to and Figures 1 to 14 Parts with the same shape are labeled with the same number and detailed descriptions are omitted.

[0191] exist Figure 15 In the wiring substrate 10 shown, multiple (in this case, two) dummy wiring layers 30A and 30B (first dummy wiring layer 30A and second dummy wiring layer 30B) with different aperture ratios are arranged around the grid wiring layer 20. Specifically, the first dummy wiring layer 30A is arranged around the grid wiring layer 20, and the second dummy wiring layer 30B is arranged around the first dummy wiring layer 30A. These dummy wiring layers 30A and 30B are different from the grid wiring layer 20 and do not actually function as antennas.

[0192] like Figure 16 As shown, the first dummy wiring layer 30A is composed of repeated dummy wirings 30a1 with a predetermined pattern shape. Similarly, the second dummy wiring layer 30B is composed of repeated dummy wirings 30a2 with a predetermined pattern shape. That is, dummy wiring layers 30A and 30B each contain a plurality of dummy wirings 30a1 and 30a2, each dummy wiring 30a1 and 30a2 being electrically independent from the grid wiring layer 20. Furthermore, the dummy wirings 30a1 and 30a2 are regularly arranged throughout the entire area of ​​the dummy wiring layers 30A and 30B, respectively. Each dummy wiring 30a1 and 30a2 is separated from each other in the planar direction and is prominently positioned on the substrate 11. Each dummy wiring 30a1 and 30a2 is electrically independent from the grid wiring layer 20, the first isolated wiring 35, the second isolated wiring 36, the power supply section 40, and other dummy wirings 30a1 and 30a2. The shapes of each dummy wiring 30a1 and 30a2 are roughly L-shaped when viewed from above.

[0193] In this case, the dummy wirings 30a1 and 30a2 have shapes formed by a partial absence of the pattern shape of the aforementioned mesh wiring layer 20. Therefore, the differences between the mesh wiring layer 20 and the first dummy wiring layer 30A, and the differences between the first dummy wiring layer 30A and the second dummy wiring layer 30B, are difficult to discern visually, making the mesh wiring layer 20 disposed on the substrate 11 difficult to see. Figure 16As shown, dummy wirings 30a1 and 30a2 extend parallel to either the first-direction wiring 21 or the second-direction wiring 22. Specifically, dummy wiring 30a1 includes a first portion 31a1 extending parallel to the first-direction wiring 21 and a second portion 32a1 extending parallel to the second-direction wiring 22. Dummy wiring 30a2 includes a first portion 31a2 extending parallel to the first-direction wiring 21 and a second portion 32a2 extending parallel to the second-direction wiring 22.

[0194] Furthermore, the area of ​​each dummy wiring 30a1 in the first dummy wiring layer 30A is larger than the area of ​​each dummy wiring 30a2 in the second dummy wiring layer 30B. In this case, the linewidth of each dummy wiring 30a1 is the same as the linewidth of each dummy wiring 30a2, but this is not a limitation; the linewidth of each dummy wiring 30a1 may also be larger than the linewidth of each dummy wiring 30a2. Moreover, the other structures of the dummy wirings 30a1 and 30a2 are the same as the structure of the dummy wiring 30a in the third variation example, therefore detailed descriptions are omitted here.

[0195] In this modified example, it is preferable that the aperture ratio of the mesh wiring layer 20 and the plurality of dummy wiring layers 30A, 30B increases progressively from the mesh wiring layer 20 toward the dummy wiring layers 30A, 30B further away from the mesh wiring layer 20. In other words, the aperture ratio of each dummy wiring layer preferably increases gradually from a position close to the mesh wiring layer 20 toward a position further away from the mesh wiring layer 20. In this case, the aperture ratio of the first dummy wiring layer 30A is preferably larger than the aperture ratio of the mesh wiring layer 20. The aperture ratio of the second dummy wiring layer 30B is preferably larger than the aperture ratio of the first dummy wiring layer 30A. As a result, the outer edges of the mesh wiring layer 20 and the dummy wiring layers 30A, 30B can be made less clear. Therefore, the mesh wiring layer 20 can be made more difficult to see on the surface of the image display device 60.

[0196] In this way, by configuring dummy wiring layers 30A and 30B that are electrically independent of the mesh wiring layer 20, the outer edge of the mesh wiring layer 20 can be made less distinct. Therefore, the mesh wiring layer 20 can be made difficult to see on the surface of the image display device 60, making it difficult for the user of the image display device 60 to visually identify it. Alternatively, three or more dummy wiring layers with different aperture ratios can be provided around the mesh wiring layer 20.

[0197] Figure 17 A fifth modified example of the wiring substrate is shown. Figure 17 In the variant shown, the planar shape of the mesh wiring layer 20 is different, but the other structures are the same as described above. Figures 1 to 16 The shapes shown are roughly the same. Figure 17 In the middle, to and Figures 1 to 16Parts with the same shape are labeled with the same number and detailed descriptions are omitted.

[0198] exist Figure 17 In the diagram, the first directional wiring 21 and the second directional wiring 22 intersect at an angle (not at a right angle), and each opening 23 forms a rhombus shape when viewed from above. The first directional wiring 21 and the second directional wiring 22 are not parallel to either the X or Y direction, but it is also possible that either the first directional wiring 21 or the second directional wiring 22 is parallel to either the X or Y direction. Additionally, the first isolated wiring 35 and the second isolated wiring 36 intersect at an angle (not at a right angle). The first isolated wiring 35 and the second isolated wiring 36 are not parallel to either the X or Y direction, but it is also possible that either the first isolated wiring 35 or the second isolated wiring 36 is parallel to either the X or Y direction.

[0199] The constituent elements disclosed in the above embodiments and variations may be appropriately combined as needed. Alternatively, several constituent elements may be deleted from all the constituent elements shown in the above embodiments and variations.

Claims

1. A wiring substrate comprising: a substrate having transparency; and a mesh wiring layer provided on the substrate, the mesh wiring layer including a wiring, an opening portion being formed by being surrounded by the wiring, and an isolated wiring being provided in the opening portion and being electrically independent of the wiring.

2. The wiring substrate according to claim 1, wherein an area ratio of the isolated wiring in the opening portion is 0.1% or more and 0.3% or less.

3. The wiring substrate according to claim 1 or 2, wherein a distance between the wiring and the isolated wiring is 4.0 μm or more and 400 μm or less.

4. The wiring substrate according to any one of claims 1 to 3, wherein a pitch of the isolated wiring is 500 μm or less.

5. The wiring substrate according to any one of claims 1 to 4, wherein a line width of the isolated wiring is 3.0 μm or less.

6. The wiring substrate according to any one of claims 1 to 5, wherein a length of the isolated wiring is 50 μm or less.

7. The wiring substrate according to any one of claims 1 to 6, wherein the isolated wirings are separated from each other by a gap, and a length of the gap is 4.0 μm or more and 400 μm or less.

8. The wiring substrate according to any one of claims 1 to 7, wherein a pitch of the wiring is 500 μm or more and 10 mm or less.

9. The wiring substrate according to any one of claims 1 to 8, wherein a line width of the wiring is 3.0 μm or less.

10. The wiring substrate according to any one of claims 1 to 9, wherein an opening ratio of the mesh wiring layer is 98% or more and less than 100%.

11. The wiring substrate according to any one of claims 1 to 10, wherein at least one of the wiring and the isolated wiring is irregularly provided.

12. The wiring substrate according to any one of claims 1 to 11, wherein a dummy wiring layer that is electrically independent of the mesh wiring layer is provided around the mesh wiring layer.

13. The wiring substrate according to claim 12, wherein a plurality of the dummy wiring layers are provided, and an opening ratio of the mesh wiring layer and the dummy wiring layers gradually increases from the mesh wiring layer toward the dummy wiring layers that are farther from the mesh wiring layer.

14. The wiring substrate according to any one of claims 1 to 13, wherein the wiring substrate has a radio wave transceiving function.

15. An image display device comprising: the wiring substrate according to claim 14; and a display device that is laminated to the wiring substrate.

16. A manufacturing method of a wiring substrate comprising: a step of preparing a substrate having transparency; and a step of forming a mesh wiring layer on the substrate, the mesh wiring layer including a wiring, an opening portion being formed by being surrounded by the wiring, and an isolated wiring being provided in the opening portion and being electrically independent of the wiring. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

Images