Module, image display device, and method for manufacturing module

Abstract

This module comprises: a wiring board having a transparent substrate and a mesh wiring layer disposed on the substrate; and a power supply line electrically connected to the wiring board. The mesh wiring layer has a millimeter wave communication antenna function and an object detection radar function. A high-frequency circuit is formed on a feeder line. The high-frequency circuit is capable of demultiplexing a signal wave for millimeter wave communication and a signal wave for object detection radar.

Description

Module, image display device, and method for manufacturing the module

[0001] Embodiments of this disclosure relate to a module, an image display device, and a method for manufacturing the module.

[0002] Currently, mobile devices such as smartphones, tablets, and smart glasses (AR, MR, etc.) are becoming more sophisticated, smaller, thinner, and lighter. These mobile devices use multiple communication bands. Therefore, multiple antennas are required, corresponding to each communication band. For example, mobile devices are equipped with multiple antennas, such as antennas for telephone, Wi-Fi (Wireless Fidelity), 3G (Generation), 4G (Generation), 5G (Generation), LTE (Long Term Evolution), Bluetooth (registered trademark), and NFC (Near Field Communication). However, with the miniaturization of mobile devices, the space available for antenna installation is limited, and the freedom of antenna design is narrowing. Furthermore, because antennas are built into a limited space, radio wave sensitivity is not always satisfactory.

[0003] Furthermore, there are currently technologies that utilize radio waves for purposes other than communication. For example, ISAC (Integrated Sensing and Communication), a technology that combines communication and sensing, is well known. ISAC uses radio waves to capture location information or movement, etc.

[0004] Japanese Patent Publication No. 2011-66610, Specification of Japanese Patent No. 5636735, Specification of Japanese Patent No. 5695947

[0005] Incidentally, in conventional film antennas, for example, one or more conductive mesh layers are formed on a transparent substrate. In this case, if a wiring layer for radar used to identify location information is provided on the transparent substrate, it becomes difficult to miniaturize the device. Furthermore, if a wiring layer for radar used to identify location information is provided on the transparent substrate, there is a possibility that the communication signal waves and the radar signal waves will interfere with each other.

[0006] One of the objectives of this embodiment is to provide a module, an image display device, and a method for manufacturing the module that enable miniaturization of the device and improvement of reliability.

[0007] Embodiments of this disclosure relate to the following [1] to

[10] .

[0008] [1] A module comprising a wiring board having a transparent substrate and a mesh wiring layer disposed on the substrate, and a power supply line electrically connected to the wiring board, wherein the mesh wiring layer has a millimeter-wave communication antenna function and an object detection radar function, a high-frequency circuit is formed on the power supply line, and the high-frequency circuit is capable of separating a signal wave for millimeter-wave communication and a signal wave for object detection radar.

[0009] [2] The module according to [1], wherein the mesh wiring layer includes a plurality of unit elements, and the planar shape of each unit element is hexagonal.

[0010] [3] The module according to [2], wherein the shapes of the unit elements are different from each other.

[0011] [4] The module according to any one of [1] to [3], wherein the high-frequency circuit includes a filter circuit.

[0012] [5] The module according to any one of [1] to [3], wherein the high-frequency circuit includes a switch circuit.

[0013] [6] The module according to any one of [1] to [5], wherein the high-frequency circuit has wiring for transmitting the decomposed signal waves.

[0014] [7] The power supply line has a base material, the high-frequency circuit is formed on the base material, and the base material has transparency to visible light. The module according to any one of [1] to [6].

[0015] [8] The distance from the mesh wiring layer to the high-frequency circuit is 1 mm or more and 20 mm or less. The module according to any one of [1] to [7].

[0016] [9] An image display device including the module according to any one of [1] to [8], and a display device laminated on the wiring board of the module.

[0017]

[10] A method for manufacturing a module, comprising: a step of preparing a substrate having transparency; a step of manufacturing a wiring board by forming a mesh wiring layer on the substrate; and a step of electrically connecting a power supply line to the wiring board. The mesh wiring layer has an antenna function for millimeter-wave communication and an object detection radar function. A high-frequency circuit is formed on the power supply line, and the high-frequency circuit can demultiplex a signal wave for millimeter-wave communication and a signal wave for an object detection radar. A method for manufacturing a module.

[0018] According to the embodiment of the present disclosure, it is possible to reduce the size of the device and improve the reliability.

[0019] Figure 1 is a plan view showing an image display device according to one embodiment. Figure 2 is a cross-sectional view (cross-sectional view along line II-II in Figure 1) showing an image display device according to one embodiment. Figure 3A is a plan view showing a wiring board and power supply line according to one embodiment. Figure 3B is an enlarged plan view showing a wiring board according to one embodiment (enlarged view of section IIIB in Figure 3A). Figure 4 is an enlarged plan view showing a wiring board according to one embodiment. Figure 5 is a cross-sectional view (cross-sectional view along line V-V in Figure 4) showing a wiring board according to one embodiment. Figure 6 is a cross-sectional view (cross-sectional view along line VI-VI in Figure 4) showing a wiring board according to one embodiment. Figure 7 is a cross-sectional view showing a module according to one embodiment. Figure 8A is a cross-sectional view showing a method for manufacturing a wiring board according to one embodiment. Figure 8B is a cross-sectional view showing a method for manufacturing a wiring board according to one embodiment. Figure 8C is a cross-sectional view showing a method for manufacturing a wiring board according to one embodiment. Figure 8D is a cross-sectional view showing a method for manufacturing a wiring board according to one embodiment. Figure 8E is a cross-sectional view showing a method for manufacturing a wiring board according to one embodiment. Figure 8F is a cross-sectional view showing a method for manufacturing a wiring board according to one embodiment. Figure 9A is a cross-sectional view showing a method for manufacturing a module according to one embodiment. Figure 9B is a cross-sectional view showing a method for manufacturing a module according to one embodiment. Figure 9C is a cross-sectional view showing a method for manufacturing a module according to one embodiment. Figure 10A is a cross-sectional view showing a method for manufacturing an image display device according to one embodiment. Figure 10B is a cross-sectional view showing a method for manufacturing an image display device according to one embodiment. Figure 10C is a cross-sectional view showing a method for manufacturing an image display device according to one embodiment. Figure 10D is a cross-sectional view showing a method for manufacturing an image display device according to one embodiment. Figure 11 is an enlarged plan view showing a modified example of the mesh wiring layer of a wiring board according to one embodiment. Figure 12 is an enlarged plan view showing another modified example of the mesh wiring layer of a wiring board according to one embodiment.

[0020] First, an embodiment will be described with reference to Figures 1 to 10D. Figures 1 to 10D show this embodiment.

[0021] The following figures are schematic diagrams. Therefore, the sizes and shapes of each part are exaggerated as appropriate for easy understanding. Also, modifications can be made as appropriate without departing from the technical concept. In each of the figures shown below, the same reference numerals are assigned to the same parts, and some detailed explanations may be omitted. Also, the numerical values and material names of the dimensions of each member described in this specification are merely examples of embodiments and are not limited thereto, and can be selected and used as appropriate. In this specification, terms specifying shapes and geometric conditions, such as terms like parallel, orthogonal, and perpendicular, shall be interpreted to include not only their strict meanings but also substantially the same states.

[0022] Also, in the following embodiments, the "X direction" is a direction parallel to one side of the image display device. The "Y direction" is a direction perpendicular to the X direction and parallel to the other side of the image display device. The "Z direction" is a direction perpendicular to both the X direction and the Y direction and parallel to the thickness direction of the image display device. Also, the "front surface" is the surface on the plus side of the Z direction, which is the light-emitting surface side of the image display device and faces the observer side. The "back surface" is the surface on the minus side of the Z direction, which is the side opposite to the light-emitting surface and the surface facing the observer side of the image display device.

[0023] Referring to FIGS. 1 and 2, the configuration of the image display device according to this embodiment will be described.

[0024] As shown in FIGS. 1 and 2, the image display device 60 according to this embodiment includes a module 80A having a wiring board 10 and a display device 61 laminated on the wiring board 10. Also, as shown in FIG. 2, the image display device 60 may further include a first transparent adhesive layer 95, a second transparent adhesive layer 96, a cover glass 75, and a decorative layer 74. The cover glass 75 and the decorative layer 74 are disposed on the wiring board 10 via the first transparent adhesive layer 95. Note that an impact absorption layer or the like not shown may be disposed between the first transparent adhesive layer 95 and the cover glass 75.

[0025] Module 80A comprises a wiring board 10 and a power supply line 85 electrically connected to the wiring board 10. The wiring board 10 includes a substrate 11, a mesh wiring layer 20, and a power supply unit 40. As shown in Figure 2, the substrate 11 includes a first surface 11a and a second surface 11b located opposite the first surface 11a. The mesh wiring layer 20 is arranged on the first surface 11a of the substrate 11. The power supply unit 40 is electrically connected to the mesh wiring layer 20.

[0026] As shown in Figure 2, the image display device 60 has a light-emitting surface 64. The wiring board 10 described above is located on the side of the light-emitting surface 64 (positive Z-direction) relative to the display device 61. A communication module 63 is located on the opposite side of the light-emitting surface 64 (negative Z-direction) relative to the display device 61. The cover glass 75, the decorative layer 74, the first transparent adhesive layer 95, the second transparent adhesive layer 96, the module 80A, the display device 61, and the communication module 63 are housed in a housing 62 (see Figure 1).

[0027] In the image display device 60 shown in Figures 1 and 2, radio waves of a predetermined frequency (for example, a frequency greater than 1 GHz) can be transmitted and received via the communication module 63, enabling communication. The communication module 63 includes a millimeter-wave antenna. The communication module 63 may also include any of the following: a telephone antenna, a Wi-Fi 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 mobile terminal devices such as smartphones and tablets. Furthermore, in the image display device 60 shown in Figures 1 and 2, the location information and movement of other objects can be detected via the communication module 63.

[0028] The display device 61 is, for example, an organic EL (Electro-Luminescence) display device. The display device 61 may be configured to be easily deformable. For example, the rigidity of the display device 61 may be lower than the rigidity of the cover glass 75. The display device 61 may 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 be placed on the display device 61. Note that the display device 61 is not limited to an organic EL display device. For example, the display device 61 may be another display device that has the function of emitting light itself, or it may be a micro-LED display device that includes a micro-LED element (light-emitting element). Also, the display device 61 may be a liquid crystal display device that includes a liquid crystal.

[0029] The cover glass 75 is located on the first surface 11a side of the substrate 11 of the wiring board 10. The first transparent adhesive layer 95 is located between the substrate 11 of the wiring board 10 and the cover glass 75. The decorative layer 74 is located between the cover glass 75 and the first transparent adhesive layer 95. The second transparent adhesive layer 96 is located on the second surface 11b side of the substrate 11 of the wiring board 10. Here, we will first describe the first transparent adhesive layer 95. Details of the wiring board 10 will be described later.

[0030] The first transparent adhesive layer 95 is an adhesive layer that directly or indirectly adheres the wiring board 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 be an OCA (Optical Clear Adhesive) layer. An OCA layer is a layer made, for example, as follows: First, a liquid curable adhesive layer composition containing a polymerizable compound is applied to a release film such as polyethylene terephthalate (PET). Next, an OCA sheet is obtained by curing this using, for example, ultraviolet light (UV). After laminating this OCA sheet to the object, the OCA layer is obtained by peeling off the release film. The material of the first transparent adhesive layer 95 may be an acrylic resin, a silicone resin, or a urethane resin. In particular, the first transparent adhesive layer 95 may contain an acrylic resin. In this case, it is preferable that the second transparent adhesive layer 96 contains an acrylic resin. This substantially eliminates the difference in refractive index between the first transparent adhesive layer 95 and the second transparent adhesive layer 96, making it possible to more reliably suppress the reflection of visible light at the interface between the first transparent adhesive layer 95 and the second transparent adhesive layer 96.

[0031] The first transparent adhesive layer 95 may have a visible light transmittance of 85% or more, and preferably 90% or more. There is no particular upper limit to the visible light transmittance of the first transparent adhesive layer 95, but it may be, for example, 100% or less. By setting the visible light transmittance of the first transparent adhesive layer 95 within the above range, the transparency of the image display device 60 can be increased, making the display device 61 of the image display device 60 easier to see. Visible light refers to light with a wavelength of 400 nm or more and 700 nm or less. Furthermore, a visible light transmittance of 85% or more means that when the absorbance is measured on the component to be measured (for example, the first transparent adhesive layer 95), the transmittance is 85% or more in the entire wavelength range from 400 nm to 700 nm. Absorbance can be measured using a spectrophotometer (Spectrometer V-670 manufactured by JASCO Corporation).

[0032] As described above, the wiring board 10 is positioned on the light-emitting surface 64 side of the display device 61. In this case, the wiring board 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 board 10 is positioned 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 a larger area than the substrate 11 of the wiring board 10. In this way, by positioning the substrate 11 of the wiring board 10 in a portion of the image display device 60 rather than the entire surface in a plan view, the area of ​​the wiring board 10 can be reduced. Therefore, when manufacturing the first directional wiring 21 and second directional wiring 22 of the wiring board 10, which will be described later, a large number of first directional wiring 21 and second directional wiring 22 can be manufactured at once. Therefore, the manufacturing cost per wiring board 10 can be reduced. Alternatively, the substrate 11 of the wiring board 10 may be placed across the entire surface of the image display device 60 in a plan view. In this case, the time required for positioning when placing the wiring board 10 on the display device 61 can be reduced.

[0033] As described above, the wiring board 10 has a transparent substrate 11 and a mesh wiring layer 20 disposed on the first surface 11a of the substrate 11. The power supply unit 40 is electrically connected to the mesh wiring layer 20. The power supply unit 40 is electrically connected to the communication module 63 via a power supply line 85. Furthermore, a part of the wiring board 10 is not positioned between the first transparent adhesive layer 95 and the second transparent adhesive layer 96, but protrudes outward (towards 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 of ​​the wiring board 10 on which the power supply unit 40 is provided protrudes outward. This makes it easy to electrically connect the power supply unit 40 and the communication module 63. On the other hand, the area of ​​the wiring board 10 on which the mesh wiring layer 20 is provided is located between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. Details of the wiring board 10 will be described later.

[0034] The second transparent adhesive layer 96 is an adhesive layer that directly or indirectly adheres 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 may be an OCA (Optical Clear Adhesive) layer. The material of the second transparent adhesive layer 96 may be an acrylic resin, a silicone resin, or a urethane resin, etc. In particular, the second transparent adhesive layer 96 may contain an acrylic resin. This substantially eliminates the difference in refractive index between the first transparent adhesive layer 95 and the second transparent adhesive layer 96, and more reliably suppresses the reflection of visible light at the interface between the first transparent adhesive layer 95 and the second transparent adhesive layer 96.

[0035] The second transparent adhesive layer 96 may have a transmittance of 85% or more for visible light (light with a wavelength of 400 nm to 700 nm), and preferably 90% or more. There is no particular upper limit to the transmittance of visible light of the second transparent adhesive layer 96, but it may be, for example, 100% or less. By setting the transmittance of visible light of the second transparent adhesive layer 96 within the above range, the transparency of the image display device 60 can be increased, making the display device 61 of the image display device 60 easier to see.

[0036] In Figure 2, the thickness T of the first transparent adhesive layer 95. ３ and the thickness T of the second transparent adhesive layer 96 ４ The thickness of at least one of these is the thickness T of the substrate 11. １ It may be 1.5 times or more, preferably 2 times or more, and even more preferably 2.5 times or more. Thus, the thickness T of the substrate 11 １ The thickness T of the first transparent adhesive layer 95 ３ Or the thickness T of the second transparent adhesive layer 96 ４ By making the first transparent adhesive layer 95 or the second transparent adhesive layer 96 sufficiently thick, the region overlapping with the substrate 11 deforms in the thickness direction, absorbing the thickness of the substrate 11. This prevents the formation of steps in the first transparent adhesive layer 95 or the second transparent adhesive layer 96 at the periphery of the substrate 11, making it difficult for observers to recognize the presence of the substrate 11.

[0037] Thickness T of the first transparent adhesive layer 95 ３and the thickness T of the second transparent adhesive layer 96 ４ It is preferable that the thickness of at least one of them is 10 times or less, and more preferably 5 times or less, of the thickness T １ of the substrate 11. Thereby, the thickness T ３ of the first transparent adhesive layer 95 or the thickness T ４ of the second transparent adhesive layer 96 does not become too thick, and the overall thickness of the image display device 60 can be reduced.

[0038] Specifically, the thickness T １ of the substrate 11 may be, for example, 2.0 μm or more, 10 μm or more, and preferably 15 μm or more. By setting the thickness T １ of the substrate 11 to 2.0 μm or more, the strength of the wiring substrate 10 can be maintained, and the first-direction wiring 21 and the second-direction wiring 22 of the mesh wiring layer 20, which will be described later, can be made less likely to deform. Also, the thickness T １ of the substrate 11 may be, for example, 200 μm or less, 50 μm or less, and preferably 25 μm or less. By setting the thickness T １ of the substrate 11 to 200 μm or less, the occurrence of steps in the first transparent adhesive layer 95 and the second transparent adhesive layer 96 at the periphery of the substrate 11 can be suppressed, and the presence of the substrate 11 can be made less recognizable to an observer. Also, by setting the thickness T １ of the substrate 11 to 50 μm or less, the occurrence of steps in the first transparent adhesive layer 95 and the second transparent adhesive layer 96 at the periphery of the substrate 11 can be further suppressed, and the presence of the substrate 11 can be made even less recognizable to an observer.

[0039] The thickness T ３ of the first transparent adhesive layer 95 may be, for example, 15 μm or more, and preferably 20 μm or more. The thickness T ３ of the first transparent adhesive layer 95 may be, for example, 500 μm or less, preferably 300 μm or less, and more preferably 250 μm or less. When the thickness T ３ of the first transparent adhesive layer 95 is 500 μm or less, the thickness T ３ of the first transparent adhesive layer 95 does not become too thick, and the overall thickness of the image display device 60 can be reduced. Also, the thickness T ３Since the thickness is 300 μm or less, the overall thickness of the image display device 60 can be made even thinner.

[0040] Thickness T of the second transparent adhesive layer 96 ４ The thickness of the second transparent adhesive layer 96 may be, for example, 15 μm or more, and is preferably 20 μm or more. ４ The thickness of the second transparent adhesive layer 96 is, for example, 500 μm or less, preferably 300 μm or less, and more preferably 250 μm or less. ４ Because the thickness is 500 μm or less, the thickness T of the second transparent adhesive layer 96 ４ This prevents the layer from becoming too thick, allowing the overall thickness of the image display device 60 to be reduced. Also, the thickness T of the second transparent adhesive layer 96 ４ Since the thickness is 300 μm or less, the overall thickness of the image display device 60 can be made even thinner.

[0041] Referring again to Figure 2, the cover glass 75 is positioned directly or indirectly on the first transparent adhesive layer 95. The cover glass 75 is located on the positive Z-direction side of the first transparent adhesive layer 95 and is positioned on the decorative layer 74. This cover glass 75 is a light-transmitting glass component. The cover glass 75 is plate-shaped, and its shape may be rectangular in plan view. The thickness of the cover glass 75 may be, for example, 200 μm or more and 1000 μm or less, and preferably 300 μm or more and 700 μm or less. The length of the cover glass 75 in the longitudinal direction (Y direction) may 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 direction (X direction) may be 20 mm or more and 500 mm or less, preferably 50 mm or more and 100 mm or less.

[0042] The decorative layer 74 is positioned on the first transparent adhesive layer 95, at least in part. The decorative layer 74 may also be a decorative film. The decorative layer 74 has, for example, an opening in all or part of the portion that overlaps with the display area of ​​the display device 61 as viewed from the observer's side, thereby shielding the portion other than the display area from light. That is, the decorative layer 74 is positioned to cover the edge of the display device 61 as viewed from the observer's side.

[0043] As shown in Figure 1, the shape of the image display device 60 is approximately rectangular in plan view, with its longitudinal direction parallel to the Y direction and its transverse direction parallel to the X direction. The length L of the longitudinal direction (Y direction) of the image display device 60. ４ The length L of the image display device 60 in the short direction (X direction) can be selected, for example, within the range of 20 mm to 500 mm, preferably 100 mm to 200 mm. ５ For example, it can be selected within a range of 20 mm to 500 mm, preferably 50 mm to 100 mm. The planar shape of the image display device 60 may be a rectangle with rounded corners.

[0044] Next, the configuration of the wiring board will be described with reference to Figures 3A to 6. Figures 3A to 6 are diagrams showing the wiring board according to this embodiment.

[0045] The wiring board 10 according to this embodiment is a substrate used in the image display device 60 described above (see Figures 1 and 2). The wiring board 10 is located on the light-emitting surface 64 side of the display device 61 and can be placed between the first transparent adhesive layer 95 and the second transparent adhesive layer 96 (see Figure 2). As shown in Figure 3A, such a wiring board 10 has, as described above, a transparent substrate 11 and a mesh wiring layer 20 disposed on the substrate 11. A power supply unit 40 is electrically connected to the mesh wiring layer 20.

[0046] The substrate 11 has a roughly rectangular shape in plan view. In the illustrated example, its longitudinal direction is parallel to the X direction, and its transverse direction is parallel to the Y direction. The substrate 11 is transparent and roughly flat, and its thickness is roughly uniform overall. The length L of the substrate 11 in the longitudinal direction (Y direction) of the image display device 60. １ (See Figure 1) can be selected within a range of, for example, 10 mm to 200 mm. The length L of the substrate 11 in the short direction (X direction) of the image display device 60. ２ (See Figure 1) can be selected within a range of, for example, 3 mm to 100 mm. The planar shape of the substrate 11 may be a rectangle with rounded corners.

[0047] The material of the substrate 11 may be any material having transparency in the visible light region and electrical insulation properties. Preferably, the material of the substrate 11 is an organic insulating material such as polyester resin, acrylic resin, polycarbonate resin, polyimide resin, polyolefin resin, cellulose resin, or fluororesin material. Polyester resin may be polyethylene terephthalate, etc. Acrylic resin may be polymethyl methacrylate, etc. Polyolefin resin may be cycloolefin polymer, etc. Cellulose resin may be triacetylcellulose, etc. Fluororesin material may be PTFE or PFA, etc. For example, as the material of the substrate 11, an organic insulating material such as cycloolefin polymer (e.g., ZF-16 manufactured by Nippon Zeon Co., Ltd.) may be used. Furthermore, depending on the application, glass or ceramics may be appropriately selected as the material of the substrate 11. Although the illustration shows an example where the substrate 11 is composed of a single layer, it is not limited to this, and may have a structure in which multiple substrates or layers are laminated. Furthermore, the substrate 11 may be a film-like material or a plate-like material.

[0048] The dielectric loss tangent of the substrate 11 is preferably 0.002 or less. By having the dielectric loss tangent of the substrate 11 within the above range, the loss of gain (decrease in sensitivity) associated with the transmission and reception of electromagnetic waves can be reduced, especially when the electromagnetic waves (e.g., millimeter waves) transmitted and received by the mesh wiring layer 20 are of high frequency.

[0049] The relative permittivity of the substrate 11 is preferably 2 or more and 10 or less. Having a relative permittivity of 2 or more allows for a wider range of material choices for the substrate 11. Furthermore, having a relative permittivity of 10 or less reduces the gain loss associated with the transmission and reception of electromagnetic waves. That is, when the relative permittivity of the substrate 11 is high, the influence of the substrate 11's thickness on electromagnetic wave propagation increases. Also, if there is an adverse effect on electromagnetic wave propagation, the dielectric loss tangent of the substrate 11 increases, potentially leading to a larger gain loss associated with the transmission and reception of electromagnetic waves. In contrast, having a relative permittivity of 10 or less reduces the influence of the substrate 11's thickness on electromagnetic wave propagation. Therefore, the gain loss associated with the transmission and reception of electromagnetic waves can be reduced. In particular, when the electromagnetic waves (e.g., millimeter waves) transmitted and received by the mesh wiring layer 20 are high-frequency, the gain loss associated with the transmission and reception of electromagnetic waves can be reduced.

[0050] The dielectric loss tangent and relative permittivity of the substrate 11 can be measured in accordance with IEC 62562. Specifically, first, a test specimen is prepared by cutting out a portion of the substrate 11 where the mesh wiring layer 20 is not formed. The dimensions of the test specimen shall be a width of 10 mm to 20 mm and a length of 50 mm to 100 mm. Next, the dielectric loss tangent or relative permittivity is measured in accordance with IEC 62562.

[0051] 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 to 700 nm) is 85% or more. The substrate 11 may have a visible light transmittance of 85% or more, but it is preferably 90% or more. There is no particular upper limit to the visible light transmittance of the substrate 11, but it may be, for example, 100% or less. By setting the visible light transmittance of the substrate 11 within the above range, the transparency of the wiring board 10 is increased, making the display device 61 of the image display device 60 easier to see.

[0052] In this embodiment, the mesh wiring layer 20 has both a millimeter-wave communication antenna function and an object detection radar function. That is, the mesh wiring layer 20 consists of an antenna pattern that functions as an antenna. This mesh wiring layer 20 may also be configured as an array antenna. When the mesh wiring layer 20 is configured as an array antenna in this way, the performance of the millimeter-wave antenna that transmits and receives highly directional millimeter waves can be improved. An array antenna is an antenna in which a plurality of antenna elements (radiating elements) are arranged regularly, and the amplitude and phase of the excitation of the elements can be controlled independently.

[0053] Furthermore, as described above, the mesh wiring layer 20 has an object detection radar function. In this case, the mesh wiring layer 20 is configured to detect the position information and movement of other objects by using radio waves.

[0054] As shown in Figure 3A, multiple mesh wiring layers 20 are formed on the substrate 11. In the illustrated example, two mesh wiring layers 20 are formed on the substrate 11 (see Figure 1). Also, as shown in Figure 3A, the mesh wiring layers 20 do not necessarily cover the entire surface of the substrate 11, but may be present only in a portion of the substrate 11. Furthermore, only one mesh wiring layer 20 may be formed on the substrate 11, or three or more may be formed.

[0055] The mesh wiring layer 20 may contain multiple unit elements 20a. In the illustrated example, each unit element 20a is directly connected to one another. Each mesh wiring layer 20 contains eight unit elements 20a. Specifically, in each mesh wiring layer 20, two rows R are arranged in series along a predetermined direction (Y direction), with four unit elements 20a arranged in series along the predetermined direction (Y direction). However, the arrangement is not limited to this, and the number of unit elements arranged along the predetermined direction and the number of rows arranged along the direction perpendicular to the predetermined direction are arbitrary. It is preferable that the rows R are arranged in close proximity to each other. By arranging two rows R, an electric field with opposite phases is generated between the unit elements 20a of one row R and the unit elements 20a of the other row R in the parts that are close to each other. Therefore, by arranging the rows R in close proximity to each other, interference between the rows R can be effectively suppressed.

[0056] In the mesh wiring layer 20, the corresponding frequency changes by changing the planar shape or size of each unit element 20a. That is, by adjusting the planar shape or size of the unit element 20a, the mesh wiring layer 20 can be made to correspond to a specific frequency. In addition, the output can be increased by increasing the number of unit elements 20a. That is, the magnitude of the output can be adjusted by the length of the direction in which multiple unit elements 20a are arranged in series (Y direction). In this case, the mesh wiring layer 20 functions as a traveling wave antenna. Furthermore, in the mesh wiring layer 20, the output can be increased by increasing the number of rows arranged along the direction (X direction) perpendicular to the direction in which multiple unit elements 20a are arranged (Y direction).

[0057] In this embodiment, the planar shape of each unit element 20a is hexagonal. The hexagonal planar shape of the unit elements 20a suppresses interference between them, thereby improving antenna performance and radar functionality. In the illustrated example, the planar shape of each unit element is a regular hexagon. However, this is not limited to this, and the planar shape of the unit elements may be other polygons. In these cases, the corners of the polygons may be rounded. Furthermore, the planar shape of the unit elements may be circular or elliptical.

[0058] Furthermore, each unit element 20a may include a skeletal portion 20b and a patch portion 20c provided inside the skeletal portion 20b. This patch portion 20c plays a role in improving the overall performance of the antenna by optimizing communication, the transmission range of radar signals, and signal strength through the efficient radiation of electromagnetic waves. The patch portion 20c is configured to increase the radiated power in order to improve the radiation performance in communication and radar functions.

[0059] In the illustrated example, the planar shape of the frame 20b is hexagonal. The patch portion 20c extends within the frame 20b along a direction (X direction) perpendicular to the direction (Y direction) in which the unit elements 20a are arranged. The patch portion 20c may also extend in a direction not parallel to the X direction. By arranging the unit elements 20a in this way, an electric field with opposite phases is generated in the parts that are close to each other between the unit elements 20a of one row R and the unit elements 20a of the other row R. This effectively suppresses interference between each unit element 20a. As shown in Figure 3A, a part of the patch portion 20c may be cut out. The patch portion 20c is configured so that the operating bandwidth and radiation performance can be freely adjusted by adjusting the length (distance in the X direction) and width (distance in the Y direction). This makes it possible to adjust the patch portion 20c to provide optimal radiation efficiency and bandwidth performance in specific communication and radar frequency bands.

[0060] The shapes of the unit elements 20a may differ from each other. This allows for compatibility with radio waves of various frequencies. Furthermore, the differing shapes of the unit elements 20a suppress the occurrence of moiré patterns. In the illustrated example, in one row R (the row on the negative X-direction side), the size of the unit elements 20a gradually decreases as it moves away from the power supply unit 40. On the other hand, in the other row R (the row on the positive X-direction side), the size of the unit elements 20a gradually increases as it moves away from the power supply unit 40. This minimizes the spacing between the unit elements 20a in the so-called EH mode, which is a type of transmission line mode. Therefore, the density of unit elements 20a in the mesh wiring layer 20 can be efficiently increased. The shapes of each unit element 20a may be similar to each other.

[0061] As described above, in each mesh wiring layer 20, rows R, each consisting of multiple (four) unit elements 20a arranged in series along a predetermined direction (Y direction), are arranged in two rows along a direction perpendicular to the predetermined direction (X direction). Furthermore, as described above, it is preferable that the rows R are arranged in close proximity to each other. In this case, the unit elements 20a of one row are in close proximity to the unit elements 20a of the other row. This allows for more effective suppression of interference between the unit elements 20a of one row R and the unit elements 20a of the other row R due to the electric fields with opposite phases generated between them. As a result, high isolation characteristics can be obtained. In this case, as shown in Figure 3B, the distance D1 between the unit elements 20a of one row and the unit elements 20a of the other row may be 0.1 mm or more and 4 mm or less. A distance D1 of 0.1 mm or more reduces the risk of the unit elements 20a short-circuiting each other. Furthermore, by having a distance D1 of 4 mm or less, interference between the unit elements 20a of one row R and the unit elements 20a of the other row R can be suppressed more effectively. Also, the distance D2 between the patch portion 20c of the unit elements 20a of one row and the patch portion 20c of the unit elements 20a of the other row may be between 0.1 mm and 4 mm. By having a distance D2 of 0.1 mm or more, the risk of short circuits between the unit elements 20a can be suppressed. Also, by having a distance D2 of 4 mm or less, interference between the unit elements 20a of one row R and the unit elements 20a of the other row R can be suppressed more effectively.

[0062] As shown in Figure 4, each mesh wiring layer 20 has a pattern shape in which 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 (for example, the Y direction) (first direction wiring 21, which will be described later) and a portion extending in a second direction (for example, the X direction) (second direction wiring 22, which will be described later).

[0063] The mesh wiring layer 20 has multiple wirings. Specifically, the mesh wiring layer 20 has multiple first-directional wirings (wirings) 21 and multiple second-directional wirings (wirings) 22 that connect the multiple first-directional wirings 21. The multiple first-directional wirings 21 and the multiple second-directional wirings 22 are arranged protruding from the substrate 11. The multiple first-directional wirings 21 and the multiple second-directional wirings 22 as a whole form a grid-like or mesh-like shape. Each first-directional wiring 21 extends in the longitudinal direction (Y direction) of the mesh wiring layer 20. Each second-directional wiring extends linearly in the width direction (X direction) of the mesh wiring layer 20. Note that the first-directional wirings 21 and the second-directional wirings 22 may extend in directions that are not parallel to either the X direction or the Y direction.

[0064] In the mesh wiring layer 20, openings 23 are formed by being surrounded by wiring. Specifically, in the mesh wiring layer 20, multiple openings 23 are formed by being surrounded by adjacent first-directional wiring 21 and adjacent second-directional wiring 22. A transparent substrate 11 is exposed through each opening 23. This increases the overall transparency of the wiring substrate 10.

[0065] The planar shape of each opening 23 is approximately square in plan view. That is, the first directional wiring 21 and the second directional wiring 22 are arranged at equal intervals from each other. Multiple first directional wirings 21 are arranged at equal intervals from each other, with a pitch P １ For example, it may be in the range of 0.01 mm to 10 mm, or in the range of 500 μm to 10 mm. Also, the multiple second directional wirings 22 are arranged at equal intervals from each other, and their pitch P ２ For example, the range may be between 0.01 mm and 10 mm, or between 500 μm and 10 mm. In this way, by arranging multiple first directional wirings 21 and multiple second directional wirings 22 at equal intervals, the size of the openings 23 within the mesh wiring layer 20 is eliminated, making the mesh wiring layer 20 difficult to see with the naked eye. Also, the pitch P of the first directional wirings 21 １ The pitch P of the second direction wiring 22 is２ This is equivalent to the above. Therefore, as described above, each opening 23 is approximately square in plan view, 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 board 10 can be increased. Note that the length of one side of each opening 23 is L. ３ For example, the thickness may be in the range of 0.01 mm to 10 mm, or in the range of 500 μm to 10 mm. Although each first directional wiring 21 and each second directional wiring 22 are perpendicular to each other, they are not limited to this and may intersect each other at an acute or obtuse angle. Furthermore, while it is preferable that the shape and size of the opening 23 be the same across the entire surface, it does not have to be uniform across the entire surface, for example, by varying it in different locations.

[0066] As shown in Figure 5, each first directional wiring 21 has a shape in which the cross section perpendicular to its longitudinal direction (cross section in the X direction) is approximately rectangular or approximately square. In this case, the cross-sectional shape of the first directional wiring 21 is approximately uniform along the longitudinal direction (Y direction) of the first directional wiring 21. As shown in Figure 6, each second directional wiring 22 has a cross section perpendicular to its longitudinal direction (cross section in the Y direction) that is approximately rectangular or approximately square, and has approximately the same shape as the cross-sectional shape (cross section in the X direction) of the first directional wiring 21 described above. In this case, the cross-sectional shape of the second directional wiring 22 is approximately uniform along the longitudinal direction (X direction) of the second directional wiring 22. The cross-sectional shapes of the first directional wiring 21 and the second directional wiring 22 do not necessarily have to be approximately rectangular or approximately square. For example, the cross-sectional shape of the first directional wiring 21 and the cross-sectional shape of the second directional wiring 22 may be a roughly trapezoidal shape where the front side (positive Z-direction side) is narrower than the back side (negative Z-direction side), or a shape in which the sides located on both sides in the longitudinal direction are curved.

[0067] In this embodiment, the line width W of the first directional wiring 21 １ (See Figure 5) and the line width W of the second direction wiring 22 ２ (See Figure 6) is not particularly limited and can be appropriately selected depending on the application. Here, the line width W of the first direction wiring 21. １ This is the width (distance in the X direction) in a cross-section perpendicular to its longitudinal direction, and is the line width W of the second direction wiring 22. ２This is the width (Y-direction distance) in a cross-section perpendicular to its longitudinal direction. For example, the line width W of the first direction wiring 21. １ The line width W of the second directional wiring 22 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. ２ The particle size 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.

[0068] Height H of the first direction wiring 21 １ (See Figure 5) and the height H of the second direction wiring 22 ２ (See Figure 6) is not particularly limited and can be appropriately selected depending on the application. Here, the height H of the first direction wiring 21 １ and the height H of the second direction wiring 22 ２ These are the lengths in the Z direction. The height H of the first direction wiring 21. １ and the height H of the second direction wiring 22 ２ Each of these can be selected within a range of, for example, 0.1 μm or more, and preferably 0.2 μm or more. Height H of the first directional wiring 21 １ and the height H of the second direction wiring 22 ２ Each of these can be selected within a range of, for example, 5.0 μm or less, and preferably 2.0 μm or less.

[0069] The material of the first directional wiring 21 and the second directional wiring 22 may be any conductive metallic material. In this embodiment, the material of the first directional wiring 21 and the second directional wiring 22 is copper, but is not limited to this. The material of the first directional wiring 21 and the second directional wiring 22 may be, for example, a metallic material such as gold, silver, copper, platinum, tin, aluminum, iron, or nickel, or an alloy containing these metals. Furthermore, the first directional wiring 21 and the second directional wiring 22 may be a plated layer formed by an electroplating method.

[0070] The overall aperture ratio At of the mesh wiring layer 20 may 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 within this range, the conductivity and transparency of the wiring substrate 10 can be ensured. Preferably, the overall aperture ratio At of the mesh wiring layer 20 is 95% or more and less than 100%, and more preferably 98% or more and less than 100%. This ensures the conductivity of the wiring substrate 10 while also increasing its transparency. The aperture ratio refers to the ratio (%) of the area of ​​the aperture region to the unit area of ​​a predetermined region (for example, the entire area of ​​the mesh wiring layer 20). The aperture region refers to the area where there are no metal parts such as the first directional wiring 21 and the second directional wiring 22, and the substrate 11 is exposed.

[0071] Although not shown in the figures, a protective layer may be formed on the first surface 11a of the substrate 11 so as to cover the mesh wiring layer 20. The protective layer protects the mesh wiring layer 20 and is formed so as to cover at least the mesh wiring layer 20 of the substrate 11. As the material for the protective layer, a colorless, transparent insulating resin such as polymethyl (meth)acrylate, polyethyl (meth)acrylate, acrylic resins and their modified resins and copolymers, polyester, polyvinyl alcohol, polyvinyl acetate, polyvinyl acetal, polyvinyl butyral, polyvinyl resins and their copolymers, polyurethane, epoxy resin, polyamide, or chlorinated polyolefin can be used.

[0072] Referring again to Figure 3A, the power supply unit 40 is electrically connected to the mesh wiring layer 20. This power supply unit 40 consists of a roughly rectangular conductive thin plate-like member. The longitudinal direction of the power supply unit 40 is parallel to the X direction, and the short direction of the power supply unit 40 is parallel to the Y direction.

[0073] Furthermore, the power supply unit 40 is located at the longitudinal end (the negative Y-direction end) of the substrate 11. The material of the power supply unit 40 can be, for example, a metallic material such as gold, silver, copper, platinum, tin, aluminum, iron, or nickel, or an alloy containing these metals.

[0074] The power supply unit 40 is electrically connected to the communication module 63 of the image display device 60 (see Figures 1 and 2) via a power supply line 85 when the wiring board 10 is incorporated into the image display device 60. The power supply unit 40 is provided on the first surface 11a of the board 11, but is not limited to this, and part or all of the power supply unit 40 may be located outside the periphery of the board 11. Furthermore, by forming the power supply unit 40 flexibly, it may be configured to wrap around to the side or back of the image display device 60. In this case, the power supply unit 40 may be electrically connected to the communication module 63 on the side or back of the image display device 60.

[0075] The power supply unit 40 is electrically connected to the mesh wiring layer 20 on the positive side in the Y direction. In this case, the power supply unit 40 is formed integrally with the mesh wiring layer 20. Thickness T of the power supply unit 40 ５ (Z-direction distance, see Figure 6) is the height H of the first direction wiring 21. １ (See Figure 5) and the height H of the second direction wiring 22 ２ (See Figure 6) This can be the same as the above, and can be selected, for example, within the range of 0.1 μm to 5.0 μm.

[0076] Next, the configuration of module 80A will be described in detail with reference to Figure 7. Figure 7 is a diagram showing module 80A according to this embodiment.

[0077] As shown in Figure 7, module 80A comprises the wiring board 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 incorporated into the image display device 60, the power supply unit 40 of the wiring board 10 is electrically connected to the communication module 63 of the image display device 60 via the power supply line 85.

[0078] The power supply line 85 is crimped to the wiring board 10 via an anisotropic conductive film (ACF) 85c. The anisotropic conductive film 85c contains a resin material such as acrylic resin or epoxy resin and conductive particles 85d. In the illustrated example, the anisotropic conductive film 85c covers a part of the power supply section 40. This helps to suppress corrosion of the power supply section 40.

[0079] The anisotropic conductive film 85c is positioned opposite the power supply unit 40. A portion of the conductive particles 85d are in contact with the power supply unit 40. This electrically connects the power supply line 85 to the power supply unit 40. Note that a portion of the anisotropic conductive film 85c may dissolve around the power supply line 85 when the power supply line 85 is crimped to the wiring board 10. The particle size of the conductive particles 85d may be, for example, about 7.0 μm.

[0080] The power supply line 85 may be, for example, a flexible printed circuit board. The power supply line 85 has a base material 85a and a metal wiring section 85b laminated on the base material 85a. The base material 85a may contain, for example, a resin material such as polyimide or a liquid crystal polymer. It is also preferable that the base material 85a is transparent to visible light. The metal wiring section 85b may contain, for example, copper. This metal wiring section 85b is electrically connected to the power supply section 40 via conductive particles 85d.

[0081] Referring again to Figures 2 and 3A, in this embodiment, a high-frequency circuit 87 is formed on the power supply line 85. The high-frequency circuit 87 is formed on the substrate 85a. This high-frequency circuit 87 is capable of separating signal waves for millimeter-wave communication from signal waves for object detection radar. That is, the radio waves received in the mesh wiring layer 20 are configured to be separated by the high-frequency circuit 87. This makes it possible to select signal waves of communication frequency from signal waves of radar frequency. Furthermore, this suppresses interference between the signal waves for communication and the signal waves for radar, thereby improving the reliability of module 80A.

[0082] The high-frequency circuit 87 may include a filter circuit. This allows for the selection of signal waves at communication frequencies from signal waves at radar frequencies. Alternatively, the high-frequency circuit 87 may include a switch circuit. In these cases, the signal waves at communication frequencies and signal waves at radar frequencies can be easily selected, and the module 80A can be miniaturized. The high-frequency circuit 87 may also have wiring 88 for transmitting the separated signal waves.

[0083] In this embodiment, as shown in Figure 2, the distance D3 from the mesh wiring layer 20 to the high-frequency circuit 87 may be 1 mm or more and 20 mm or less. By having a distance D3 of 1 mm or more, interference between the mesh wiring layer 20 and the high-frequency circuit 87 can be suppressed. In addition to miniaturizing the module 80A, losses can be reduced. Also, by having a distance D3 of 20 mm or less, losses can be reduced in addition to miniaturizing the module 80A.

[0084] [Manufacturing Method for Wiring Board, Manufacturing Method for Module, and Manufacturing Method for Image Display Device] Next, with reference to Figures 8A to 10D, the manufacturing method for the wiring board 10, the manufacturing method for the module 80A, and the manufacturing method for the image display device 60 according to this embodiment will be described. Figures 8A to 8F are cross-sectional views showing the manufacturing method for the wiring board 10 according to this embodiment. Figures 9A to 9C are cross-sectional views showing the manufacturing method for the module 80A according to this embodiment. Figures 10A to 10D are cross-sectional views showing the manufacturing method for the image display device 60 according to this embodiment.

[0085] First, the method for manufacturing a wiring board according to this embodiment will be described with reference to Figures 8A to 8F.

[0086] First, as shown in Figure 8A, a substrate 11 is prepared, which includes a first surface 11a and a second surface 11b located on the opposite side of the first surface 11a. The substrate 11 is transparent.

[0087] Next, a mesh wiring layer 20 and a power supply unit 40 electrically connected to the mesh wiring layer 20 are formed on the first surface 11a of the substrate 11.

[0088] In this case, first, as shown in Figure 8B, a metal foil 51 is laminated over substantially the entire surface 11a of the substrate 11. In this embodiment, the thickness of the metal foil 51 may be 0.1 μm or more and 5.0 μm or less. In this embodiment, the metal foil 51 may contain copper.

[0089] Next, as shown in Figure 8C, a photocurable insulating resist 52 is supplied to substantially the entire surface of the metal foil 51. Examples of this photocurable insulating resist 52 include organic resins such as acrylic resin and epoxy resin.

[0090] Next, as shown in Figure 8D, 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 so that the metal foil 51 corresponding to the first directional wiring 21, the second directional wiring 22, the first isolated wiring 35, and the second isolated wiring 36 is covered by the insulating layer 54.

[0091] Next, as shown in Figure 8E, the metal foil 51 located on the first surface 11a of the substrate 11, in the portion not covered by the insulating layer 54, is removed. At this time, the metal foil 51 is etched so that the first surface 11a of the substrate 11 is exposed by performing a wet treatment using ferric chloride, cupric chloride, strong acids such as sulfuric acid and hydrochloric acid, persulfates, hydrogen peroxide, aqueous solutions thereof, or combinations thereof.

[0092] Next, as shown in Figure 8F, the insulating layer 54 is removed. In this case, the insulating layer 54 on the metal foil 51 is removed by wet treatment using a permanganate solution, N-methyl-2-pyrrolidone, an acid or alkaline solution, or by dry treatment using oxygen plasma.

[0093] In this way, a wiring board 10 is obtained having a substrate 11 and a mesh wiring layer 20 provided on the first surface 11a of the substrate 11. In this case, the mesh wiring layer 20 includes first directional wiring 21 and second directional wiring 22. An opening 23 is formed by being surrounded by the first directional wiring 21 and second directional wiring 22. A first isolated wiring 35 and a second isolated wiring 36 are provided within the opening 23, which are electrically independent from the first directional wiring 21 and second directional wiring 22. At this time, a power supply section 40 may be formed by a part of the metal foil. Alternatively, a flat plate-shaped power supply section 40 may be prepared separately and electrically connected to the mesh wiring layer 20.

[0094] Next, the method for manufacturing a module according to this embodiment will be described with reference to Figures 9A to 9C.

[0095] First, prepare the wiring board 10 as shown in Figure 9A. In this case, the wiring board 10 is manufactured, for example, by the method shown in Figures 8A to 8F.

[0096] 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. First, as shown in Figure 9B, the anisotropic conductive film 85c and the power supply line 85 are placed on the wiring board 10. At this time, the anisotropic conductive film 85c is placed between the power supply line 85 and the power supply unit 40.

[0097] Next, as shown in Figure 9C, the power supply line 85 is crimped to the wiring board 10. At this time, pressure and heat are applied to the power supply line 85 to the wiring board 10, and a portion of the conductive particles 85d come into contact with the power supply unit 40. In this way, the power supply line 85 is electrically connected to the power supply unit 40. At this time, a portion of the anisotropic conductive film 85c may dissolve around the power supply line 85.

[0098] In this way, a module 80A is obtained that includes a wiring board 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.

[0099] Next, with reference to Figures 10A to 10D, a method for manufacturing the image display device 60 according to this embodiment will be described.

[0100] In this process, first, as shown in Figure 10A, for example, the cover glass 75 and decorative layer 74 and the first transparent adhesive layer 95 are laminated together. At this time, a liquid curable adhesive layer composition containing a polymerizable compound may be used as the first transparent adhesive layer 95. This curable adhesive layer composition may also contain a polar group-containing monomer. When laminating the cover glass 75 and decorative layer 74 and the first transparent adhesive layer 95 together, for example, the first transparent adhesive layer 95 may be heated to about 60°C.

[0101] Next, as shown in Figure 10B, the wiring board 10 of module 80A is laminated onto the first transparent adhesive layer 95.

[0102] Next, as shown in Figure 10C, a second transparent adhesive layer 96 is laminated onto the wiring board 10. At this time, a liquid curable adhesive layer composition containing a polymerizable compound may be used as the second transparent adhesive layer 96. This curable adhesive layer composition may also contain a polar group-containing monomer. By laminating the second transparent adhesive layer 96 onto the wiring board 10 in this way, the wiring board 10 is sandwiched between the first transparent adhesive layer 95 and the second transparent adhesive layer 96. When laminating the second transparent adhesive layer 96 onto the wiring board 10, for example, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 may be heated to about 60°C.

[0103] Next, as shown in Figure 10D, the display device 61 is laminated onto the second transparent adhesive layer 96. At this time, for example, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 may be heated to about 60°C.

[0104] Next, the first transparent adhesive layer 95 and the second transparent adhesive layer 96 are cured using, for example, ultraviolet light (UV).

[0105] In this way, an image display device 60 is obtained, comprising a module 80A and a display device 61 stacked on the wiring board 10 of the module 80A.

[0106] [Operation of this Embodiment] Next, the operation of this embodiment, which has the above configuration, will be described.

[0107] As shown in Figures 1 and 2, the wiring board 10 is incorporated into an image display device 60 having a display device 61. At this time, the wiring board 10 is placed on the display device 61. The mesh wiring layer 20 of the wiring board 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. In this way, radio waves of a predetermined frequency can be transmitted and received via the mesh wiring layer 20, and communication can be performed using the image display device 60. In addition, the position information and movement of other objects can be detected via the mesh wiring layer 20.

[0108] According to this embodiment, the mesh wiring layer 20 has both a millimeter-wave communication antenna function and an object detection radar function. This makes it possible to miniaturize the module 80A. In addition, a high-frequency circuit 87 is formed on the power supply line 85, and the high-frequency circuit can separate the signal wave for millimeter-wave communication from the signal wave for object detection radar. This makes it possible to select the signal wave at the communication frequency from the signal wave at the radar frequency. Furthermore, this makes it possible to suppress interference between the communication signal wave and the radar signal wave, thereby improving the reliability of the module 80A.

[0109] Furthermore, according to this embodiment, the wiring board 10 comprises a transparent substrate 11 and a mesh wiring layer 20 disposed on the substrate 11. The mesh wiring layer 20 has a conductive portion that forms an opaque conductive layer and a mesh-like pattern with numerous openings. Therefore, the transparency of the wiring board 10 is ensured. As a result, when the wiring board 10 is placed on the display device 61, the display device 61 can be viewed through the openings 23 of the mesh wiring layer 20, and the visibility of the display device 61 is not hindered.

[0110] In the embodiment described above, an example was shown in which each unit element 20a is directly connected to one another, but this is not the only example. For example, as shown in Figure 11, each unit element 20a may be connected to one another via a connecting portion 20d. In this case, the connecting portion 20d is formed to extend along the direction (Y direction) in which each unit element 20a is connected to one another. In this case as well, each unit element 20a is connected to one another via a single connecting portion 20d. Even in this case, the electric field with opposite phases generated between the unit elements 20a of one row R and the unit elements 20a of the other row R effectively suppresses interference between the unit elements 20a of one row R and the unit elements 20a of the other row R.

[0111] Furthermore, although the above-described embodiment mentions an example where the planar shape of the skeletal part 20b is hexagonal, the invention is not limited to this. For example, as shown in Figure 12, the planar shape of the skeletal part 20b may be a shape obtained by dividing a hexagon (regular hexagon) with a diagonal that passes through the center of the hexagon. Also, as shown in Figure 12, each unit element 20a may be connected to each other via two connecting parts 20d. That is, the skeletal part 20b and the connecting parts 20d may be a shape obtained by dividing the skeletal part 20b and the connecting parts 20d shown in Figure 11 with a straight line extending along the Y direction. In this case as well, interference between the unit elements 20a of one row R and the unit elements 20a of the other row R can be effectively suppressed by the electric field with opposite phases generated between the unit elements 20a of one row R and the unit elements 20a of the other row R. Therefore, high isolation characteristics can be obtained. Furthermore, in this case as well, the spacing between unit elements 20a can be minimized in the so-called EH mode, which is a type of transmission line mode. Therefore, the density of unit elements 20a in the mesh wiring layer 20 can be efficiently increased.

[0112] It is also possible to combine the multiple components disclosed in the above embodiment as needed. Alternatively, some components may be removed from all the components shown in the above embodiment.

Claims

1. A module comprising a wiring board having a transparent substrate and a mesh wiring layer disposed on the substrate, and a power supply line electrically connected to the wiring board, wherein the mesh wiring layer has a millimeter-wave communication antenna function and an object detection radar function, and a high-frequency circuit is formed on the power supply line, and the high-frequency circuit is capable of separating a signal wave for millimeter-wave communication and a signal wave for object detection radar.

2. The module according to claim 1, wherein the mesh wiring layer includes a plurality of unit elements, and the planar shape of each unit element is hexagonal.

3. The module according to claim 2, wherein the shapes of the unit elements are different from each other.

4. The module according to claim 1, wherein the high-frequency circuit includes a filter circuit.

5. The module according to claim 1, wherein the high-frequency circuit includes a switch circuit.

6. The module according to claim 1, wherein the high-frequency circuit has wiring for transmitting a delimited signal wave.

7. The module according to claim 1, wherein the power supply line has a base material, the high-frequency circuit is formed on the base material, and the base material is transparent to visible light.

8. The module according to claim 1, wherein the distance from the mesh wiring layer to the high-frequency circuit is 1 mm or more and 20 mm or less.

9. An image display device comprising a module according to any one of claims 1 to 8, and a display device laminated on the wiring board of the module.

10. A method for manufacturing a module, comprising the steps of: preparing a transparent substrate; manufacturing a wiring board by forming a mesh wiring layer on the substrate; and electrically connecting a power supply line to the wiring board, wherein the mesh wiring layer has a millimeter-wave communication antenna function and an object detection radar function; a high-frequency circuit is formed on the power supply line; and the high-frequency circuit is capable of separating a signal wave for millimeter-wave communication and a signal wave for object detection radar.

Images