TW202215709A - Transparent Antenna and Display Module - Google Patents

Abstract

The transparent antenna 1 of the present invention includes a first transparent base material 101 , a second transparent base material 102 , first thin metal wire layers 110 and 120 on the first transparent base material 101 , and a second transparent base material 102 . 2 metal thin wire layers 130, and the aperture ratio of the first metal thin wire layers 110, 120 and the second metal thin wire layer 130 is more than 80%, and the sheet resistance of the first metal thin wire layers 110, 120 and the second metal thin wire layer 130 is 5 Ω/sq or less, the first thin metal wire layers 110 and 120 and the second thin metal wire layer 130 are not in direct current conduction, the distance between the first transparent substrate 101 and the second transparent substrate 103 is more than 100 μm, and the first thin metal wire layer 110 has a In the sheet-like antenna portion 110 , the second thin metal wire layer 130 is formed across at least a region including the antenna portion 110 in a plan view.

Description

Transparent Antenna and Display Module

The present invention relates to a transparent antenna and a display module including the transparent antenna.

In recent years, 5th Generation Mobile Communication System (5G: 5th Generation Mobile Communication System) or 6th Generation Mobile Communication System has been developed as a communication technology in mobile communication devices such as smartphones, tablets, mobile phones, and notebook personal computers. system (6G: 6th Generation Mobile Communication System), etc.

Here, the millimeter wave called the 5th generation mobile communication system (5G) has strong directivity and short reach, and is easily shielded by metals, etc. Therefore, as an antenna for 5G, it is proposed to arrange a transparent antenna on the display. (OLED (Organic Light Emitting Diode: Organic Light Emitting Diode), LCD (Liquid Crystal Display: Liquid Crystal Display), LED (Light Emitting Diode: Light Emitting Diode)), or touch panel (also includes display-integrated metal thin wires panel) technology (for example, Patent Document 1, Patent Document 2).

Since such a transparent antenna is installed on a display panel or a touch panel, it is required to be thinner for easy installation.

Here, the antenna including the patch antenna is a patch antenna including a planar element formed of a mesh and a ground layer, but the patch antenna needs a ground layer on the back surface opposite to the antenna pattern.

It is known that since a patch antenna has a ground layer, it operates more stably than an antenna without a ground layer even when the materials constituting the display or touch panel arranged on the lower side are different.

However, in Patent Document 1 or Patent Document 2, although a planar patch antenna element composed of a mesh is mentioned, the specific grounding structure is not mentioned.

Here, in the patch antenna, generally speaking, when the ground layer is separated from the layer of the antenna pattern, the antenna characteristics are improved. Therefore, in order to make the antenna performance of the transparent antenna good, the substrate in the patch antenna is thicker within the range that can be mounted. By. [Prior Art Literature] [Patent Literature]

Patent Document 1: Japanese Patent Laid-Open No. 2013-5013 Patent Document 2: US-A1-2019/0058264

[Problems to be Solved by Invention]

However, in a substrate, if the film between the antenna pattern and the ground layer is enlarged, the substrate becomes thicker by this amount, which makes the transparent antenna thicker, resulting in abnormal installation of the display module.

Therefore, in view of the above situation, the present invention aims to provide a transparent antenna, which can communicate in the 5G bandwidth, is not easily affected by the material of the display or touch panel that is approaching, and can make the overall thickness of the antenna thinner and increase the size of the antenna. performance. [Technical means to solve problems]

In order to solve the above problems, an aspect of the present invention provides a transparent antenna, The transparent antenna includes a first transparent substrate, a second transparent substrate, a first thin metal wire layer on the first transparent substrate, and a second thin metal wire layer on the second transparent substrate; and The aperture ratio of the first metal thin line layer and the second metal thin line layer is more than 80%; The sheet resistance of the first metal thin wire layer and the second metal thin wire layer is below 5 Ω/sq; The first metal thin wire layer and the second metal thin wire layer are not in direct current conduction; The first transparent substrate and the second transparent substrate are separated by more than 100 μm; The first thin metal wire layer has a patch-shaped antenna portion; The second thin metal wire layer is formed over at least a region including the antenna portion in a plan view. [Effect of invention]

According to one aspect, in the transparent antenna, the material of the display or touch panel that is approached is not easily affected, so that the overall thickness of the antenna can be reduced and the performance of the antenna can be improved.

Hereinafter, the form for implementing this invention is demonstrated with reference to drawings. In each of the following drawings, the same reference numerals may be attached to the same constituent parts, and overlapping explanations may be omitted. Hereinafter, an embodiment of the transparent antenna to which the present invention is applied will be described.

As an example, the transparent antenna 100 of the present invention can be applied to a fifth generation mobile communication system (5G), a sixth generation mobile communication system (6G), or the like.

＜Electronic equipment＞ 1 and FIG. 2, the structure of the electronic apparatus 200 which is an example of the communication apparatus equipped with the display module D containing the transparent antenna 100 of this invention is demonstrated. FIG. 1 is an overall view showing the position of the transparent antenna 100 in the electronic apparatus 200 equipped with the display module D of the present invention. FIG. 2 is a cross-sectional view of the electronic device 200 of FIG. 1 taken along the A surface.

In FIGS. 1 and 2 , the X direction refers to the longitudinal direction of the electronic device 200 (the longitudinal direction of the device), the Y direction refers to the lateral direction of the electronic device 200 (the short lateral direction of the device), and the Z direction refers to the height direction of the electronic device 200 . . Hereinafter, the XYZ coordinate system is defined and explained. In addition, for the convenience of description, a plan view means an XY plane view, and the description will be made using the vertical direction with the +Z direction side as the upper side and the -Z direction side as the lower side, and the lateral direction (lateral direction) with respect to the vertical direction. But it does not mean generally up and down directions and horizontal ones.

In addition, in parallel, right-angle, orthogonal, horizontal, vertical, up-down, left-right and other directions, deviations are allowed to the extent that the disclosure effect of the embodiment is not lost. In addition, the X direction, the Y direction, and the Z direction represent a direction parallel to the X axis, a direction parallel to the Y axis, and a direction parallel to the Z axis, respectively. The X direction, the Y direction, and the Z direction are orthogonal to each other. The XY plane, the YZ plane, and the ZX plane represent a virtual plane parallel to the X direction and the Y direction, a virtual plane parallel to the Y direction and the Z direction, and a virtual plane parallel to the Z direction and the X direction, respectively.

The electronic device 200 is, for example, an information processing terminal such as a smartphone, a tablet computer, and a notebook PC (Personal Computer). In addition, the electronic device 200 is not limited to these, and may be, for example, an electronic device including a structure such as a column or a wall, a digital signboard, a display panel in a train, or an electronic device including various display panels in a vehicle.

As shown in FIG. 1 and FIG. 2 , the entire upper surface of the electronic apparatus 200 or at least a part of the upper surface is provided with a display module D capable of performing a display function. Moreover, the transparent antenna 100 of the present invention is disposed on the upper side of the touch panel 230 on the display panel 220 . The upper side of the transparent antenna 100 of the present invention is transparent in such a way that the transparent cover 240 can be seen from outside the electronic device 200 , and the display panel 220 can be viewed from the outside through the transparent antenna 100 .

2 , in the electronic apparatus 200, the display panel 220, the touch panel 230, the transparent antenna 100, and the transparent cover 240 are combined as a display module D (also referred to as a display module).

In addition to the display module D, the electronic apparatus 200 also includes a frame body 210 , a wiring board 250 , electronic parts 260A, 260B, 260C, 260D, a battery 270 , and the like.

In FIGS. 1 and 2 , the electronic device 200 equipped with the transparent antenna 100 is shown as an example of a smart phone, but the electronic device equipped with the transparent antenna of the present invention only needs to include a frame body 210 , a transparent cover body 240 , and a display panel. 220 The electronic equipment may also be of other configurations. In addition, the electronic device 200 may also be a device without the touch panel 230 .

The frame body 210 is, for example, a case made of metal and/or resin, and covers the lower surface side and the side surface side of the electronic device 200 . The frame body 210 has an open end 211 serving as the upper end of the peripheral wall, and a transparent cover 240 is mounted on the open end 211 . The housing 210 has a housing portion 212 , which is an internal space communicating with the open end 211 , and the wiring board 250 , the electronic components 260A to 260D, the battery 270 , and the like are housed in the housing portion 212 .

An example of the cover glass, that is, the transparent cover body 240, is a transparent glass plate disposed on the uppermost surface, and has a size matching with the open end 211 of the frame body 210 when viewed from above. In this example, the transparent cover 240 is shown as an example of a glass plate whose shape is mostly flat and whose both ends in the horizontal direction (±Y direction) are gently curved downward, but it may also be a flat glass plate in the horizontal direction. Alternatively, the transparent cover 240 may have a shape in which both ends are gently curved downward in the longitudinal direction (±X direction) of the electronic device 200 . Here, the embodiment in which the transparent cover 240 is made of glass will be described, but the transparent cover 240 may be made of resin.

By attaching the transparent cover body 240 to the open end 211 of the frame body 210, the accommodating portion 212 of the frame body 210 is sealed.

The upper surface of the transparent cover 240 is an example of the outer surface of the transparent cover 240 , and the lower surface of the transparent cover 240 is an example of the inner surface of the transparent cover 240 . On the inner surface side of the transparent cover 240 , the transparent antenna 100 and the touch panel 230 are disposed. Since the transparent cover 240 is transparent, the touch panel 230 and the display panel 220 disposed inside can be seen from the outside of the electronic device 200 through the transparent cover 240 .

Electronic components 260A to 260C are mounted on the wiring board 250 . The wiring board 250 is connected to a power supply line and the like shown by the dotted line in FIG. 2 extending from the transmission area 120 (refer to FIG. 5 ) of the transparent antenna. The wiring board 250 and the transmission area 120 of the transparent antenna 100 may be connected using a connector, an Anisotropic Conductive Film (ACF), or the like, or may be connected using other components.

As an example, the electronic component 260A is a communication module that is connected to the transmission area 120 of the transparent antenna 100 through the wiring of the wiring board 250 , and processes signals transmitted or received through the transparent antenna 100 . In addition, the electronic component 260B in the center is, for example, a camera.

As an example, the electronic components 260C and 260D are components that perform information processing related to the operation of the electronic device 200 , for example, by including a CPU (Central Processing Unit: Central Processing Unit), a RAM (Random Access Memory: random access memory) ), ROM (Read Only Memory: read only memory), HDD (Hard Disk Drive: hard disk drive), input and output interfaces, and internal busbars and other computers.

The battery 270 is a rechargeable secondary battery, and supplies power required for the operation of the display module D, the electronic components 260A to 260D, and the like.

<Display module> Next, the position of the transparent antenna 100 of the present invention in the display module D is described. FIG. 3 is a schematic cross-sectional view of the display module D. FIG.

Although description is omitted in FIG. 2 , as shown in FIG. 3 , the display module D has a polarizer (Polarizer: polarizer) 280 between the touch panel 230 and the transparent cover 240 . 2, the transparent antenna 100 is constituted by two substrates of the first transparent substrate 101 and the second transparent substrate 102 so as to sandwich the polarizer 280, although it is shown as a single member.

Furthermore, in order to bond the substrates to each other between the substrates, the outermost adhesive layer, that is, the first adhesive layer 291, the second adhesive layer 292 and the third adhesive layer 293 sandwiched between the antenna substrates are provided in this order from the outside. , and the lowermost bonding layer ie the fourth bonding layer 294 . Subsequent layers 291 to 294 are composed of a transparent optical adhesive OCA (Optical Clear Adhesive: optical adhesive).

In FIG. 3 , the touch panel 230 shows an example of an “on-cell touch panel metal thin line layer” directly formed on the surface of the display panel 220 without an adhesive layer. However, an adhesive layer may also be provided between the touch panel 230 and the display panel 220 . In the configuration of FIG. 3 , the touch panel 230 provided on the display panel 220 functions as the conductive layer (first conductive layer) of the transparent antenna 100 in the display module D. As shown in FIG.

2 and 3 show an example in which the touch panel 230 is installed in the display module D, but the touch panel 230 may not be installed in the display module D installed in the electronic apparatus 200 . At this time, the display panel 220 (eg, the cathode of the OLED display panel) functions as a conductive layer in the display module D relative to the transparent antenna 100 . The sheet resistance of the conductive layer is, for example, 5 Ω/sq to 20 Ω/sq.

The conductive layer (the touch panel 230 or the display panel 220 ) and the second thin metal wire layer on the second transparent substrate 102 of the transparent antenna 100 , that is, the ground area, are not connected to each other by direct current, but in the sense of high frequencies such as the use frequency of the antenna AC power can be shared. Even if the electric power can be shared in alternating current, the conductive layer and the second metal thin wire layer of the transparent antenna can also include a non-overlapping region in a plan view. For example, in the cross-section of FIG. 2 , since the transparent antenna is partially disposed relative to the display panel 220 , the transparent antenna 100 is partially relative to the conductive layer, but the transparent antenna 100 protrudes out of the conductive layer, whereby the conductive layer is opposite to the conductive layer. The transparent antenna 100 may also be a part.

The display panel 220 is, for example, a liquid crystal display panel, an organic EL (Electro-luminescence), or an OLED (Organic Light Emitting Diode) display panel, any of which are configured in the display module D the bottom side.

In addition, in the display module D, as shown in FIG. 1 , since the transparent antenna 100 is partially arranged, the touch panel 230 , the polarizer 280 , or/and the adhesive layer 291 can also be used in the area where the transparent antenna 100 is arranged. ~294 is thinner than the other parts, or the polarizing plate 280 and/or the adhesive layers 291 to 294 are not provided. Therefore, in the display module D, only a part of the transparent antenna 100 can be prevented from protruding.

In addition, it is known that if the transparent antenna 100 is too thick, the edge portion of the transparent antenna 100 can be seen, or air is easily mixed into the boundary between the adhesive layers 291 to 294 . The thicknesses of the first transparent substrate 101 and the second transparent substrate 102 of the transparent antenna 100 are each preferably 300 μm or less, more preferably 150 μm or less, and particularly preferably 100 μm or less. In addition, from the viewpoint of ease of handling, the thickness of the transparent substrates 101 and 102 of each of the transparent antennas 100 is preferably 10 μm or more, and more preferably 50 μm or more.

Furthermore, if the transparent antenna 100 has a specific overlapping portion described later in the vertical direction, the substrate sizes of the first transparent substrate 101 and the second transparent substrate 102 may be different in the ±X direction and the ±Y direction. In addition, the thicknesses of the transparent substrates 101 and 102 constituting the transparent antenna 100 may be the same or different.

In addition, in the transparent antenna 100 of the present invention, as will be described later, the substrate 101 and the substrate 102 are not connected by wires, but are alternately connected between the substrates. , the polarizing plate 280 and the third adhesive layer 293 function as dielectrics. The dielectric constant ε of the second adhesive layer 292 , the polarizing plate 280 , and the third adhesive layer 293 as dielectrics is preferably the difference between the dielectric constant ε1 of the first transparent substrate 101 and the dielectric constant ε2 of the second transparent substrate 102 within the range.

1 and 2, the display module D is shown as an example in which both ends in the ±Y direction are in the shape of gentle curved surfaces, but the display module D may also be in a flat shape with an end surface not curved. In this case, the transparent antenna 100 may also have a planar shape. In addition, when the transparent antenna 100 is partially curved, the transmission area, which will be described later, has a curved shape.

<The first configuration example of the transparent antenna> Next, the configuration of the transparent antenna 100 according to the first configuration example of the present invention will be described with reference to FIGS. 4 to 6 . FIG. 4 is a perspective view of the transparent antenna 100 according to the first configuration example of the present invention. 5 is an explanatory diagram of the transparent antenna 100 of the first configuration example, (A) is a plan view of the first transparent substrate 101 viewed from the +Z direction, (B) is the first transparent substrate 101 viewed from the -Z direction The bottom view. 5 (C) is a top view of the second transparent base material 102 seen from the +Z direction, (D) is a bottom view of the second transparent base material 102 seen from the -Z direction. In addition, as shown in FIG. 1 , when a part of the transparent antenna 100 is arranged along a curve, in FIG. 4 , the state before the transparent antenna 100 is bent is also shown as being parallel to the XY plane.

In this configuration example, the transparent antenna 100 is provided with the antenna pattern 110 and the transmission area 120 on the upper surface (surface) side of the first transparent substrate (also referred to as the first transparent base material) 101 . The antenna pattern 110 of this configuration is an example of a patch type antenna. In addition, on the lower surface (back surface) side of the second transparent substrate 102 (also referred to as a second transparent base material), a ground region 130 that is a ground layer is provided.

As shown in FIG. 3 , between the first transparent substrate 101 and the second transparent substrate 102 , a second adhesive layer 292 , a polarizer 280 , and a third adhesive layer 293 are provided, whereby in the transparent antenna 100 , as shown in FIG. 4 The distance ds between the first transparent substrate 101 and the second transparent substrate 102 is shown to be about 150 μm apart.

Furthermore, as shown in FIG. 4 , the antenna pattern 110 is provided on the upper surface side of the first transparent substrate 101 , and the grounding region 130 is provided on the lower side of the second transparent substrate 102 . Therefore, the thin metal wire layer is the antenna pattern 110 and the grounding region 130 . The distance dm is about 500 μm away. The separation distance dm between the thin metal wire layers is 100 μm or more, preferably 200 μm or more, and more preferably 300 μm or more.

As shown in FIG. 3 , the second transparent substrate 102 is disposed above the touch panel 230 or the display panel 220 with the adhesive layer 294 sandwiched therebetween. Therefore, the product (Δnd) of the refractive index difference (Δn) with respect to the polarization direction and the thickness (d) of the substrate, that is, the lower the retardation δ2, the better. On the other hand, since the first transparent substrate 101 is separated from the touch panel 230 or the display panel 220, the phase difference δ1 may not be low. Therefore, the phase difference between the first transparent substrate 101 and the second transparent substrate 102 is preferably in the relationship of δ1≧δ2, and may be δ1>δ2.

In order to satisfy the above-mentioned retardation, the first transparent substrate 101 is PET (polyethylene terephthalate resin) or COP (cycloolefin polymer), and the second transparent substrate 102 is, for example, COP. For example, the retardation of PET is 100 μm thickness, 5061.7 nm, and the retardation of COP is 100 μm thickness, 3.77 nm.

As described above, the retardation is an amount that increases or decreases due to the complex refractive index caused by the material of the substrate when the thickness is the same, that is, the amount that affects the clarity of the image and the like. Therefore, the retardation is evaluated using light in the visible light region (wavelength 380 nm to 780 nm).

On the other hand, the dielectric constant is a quantity related to the characteristics of the antenna. Therefore, the dielectric constant is estimated in the wavelength range of the radio waves used. The dielectric constant ε2 of the second transparent substrate 102 is preferably lower than the dielectric constant ε1 of the first transparent substrate 101 . Since ε2 is low, the distance between the metal thin wires in the second metal thin wire layer is electrically narrowed, so that the leakage of radio waves from the second metal thin wire layer to the lower side is suppressed. For example, the dielectric constant of PET constituting the first transparent substrate 101 is 3.31 at 35 GHz, and the dielectric constant of the COP constituting the second transparent substrate 102 is 2.31 at 35 GHz.

Furthermore, in order to ensure that the transparent antenna 100 is colorless and transparent, the transmittance of each substrate 101 and 102 is preferably more than 80%, and any one of the transparent substrates 101 and 102 can be bent along the Z direction and/or the X direction. flexible substrate.

In the transparent antenna 100 of this configuration, in the first transparent substrate 101 on the upper side, the antenna pattern 110 is provided in the vicinity of the center in the longitudinal direction of the first transparent substrate 101 . The antenna pattern 110 of this configuration is an example of a patch type antenna.

The antenna pattern 110 , which is an antenna portion, includes a first linear element 111 and a planar patch element 112 .

Specifically, one end of the first line element 111 is a feeding point F connected to the signal line 121 of the transmission area 120, and extends from the feeding point F in the first direction (+Y direction), which is the transmission direction. The other end of the first line element 111 is connected to the planar patch element 112 .

The planar patch element (also referred to as a patch portion or a patch element) 112 is a substantially quadrangular patch antenna having a specific area. In the planar chip element 112, grooves 113 and 114 are formed in the vicinity of the boundary with the first line element 111 in the -Y direction. In this configuration, all elements of the antenna pattern 110 are provided on the upper surface side of the first transparent substrate 101 , that is, on the +Z side. The grooves 113 and 114 of the chip element 112 are provided to obtain the thickness or dielectric constant of the peripheral members of the chip element 112, the radiation resistance determined according to the size of the chip element, and the matching with the impedance of the power supply line.

Here, if the length in the first direction of the planar patch element 112 is Y112 and the length in the second direction is X112, then the first transparent antenna 100 in the resonance frequency f1 (28 GHz) of the transparent antenna 100 The wavelength on the substrate 101 is set to λ ₀₁ , Y112 is set to an integer multiple of about 0.5 λ ₀₁ , and X112 is set to a value smaller than 1.0 λ ₀₁ . Therefore, in order to improve the antenna gain of the frequency band f1, it is preferable to adjust X112 and Y112, which define the size of the planar patch element 112, to be within ±10% of about 2.5 mm, respectively.

In addition, a transfer area (also referred to as a power supply area) 120 that is a transfer portion is disposed at an end portion in the longitudinal direction (end portion on the −Y direction side) of the first transparent substrate 101 . In this configuration example, the transmission region 120 is a coplanar waveguide, and has a signal line (also called a signal line, a transmission line) 121 extending from the center of the short-side direction (±X direction) of the substrate 101 on the surface on the +Z side. , and the planar ground portions 122 and 123 which are grounded in the state of sandwiching the signal line 121 in the short-side direction. The front end in the transmission direction of the signal line 121 for transmitting the signal (power) is electrically connected to the first line element 111 of the antenna pattern 110 , and the connection point thereof becomes the power supply point F. As shown in FIG.

In this configuration example, any one of the signal line 121 and the ground portions 122 and 123 constituting the transfer region 120 is provided only on the upper surface side (+Z side) of the first transparent substrate 101 . Therefore, in the first transparent substrate 101 of this configuration, all the constituent elements of the antenna pattern 110 and the transfer region 120 that function as the first thin metal wire layer are provided on the upper surface side (+Z side) of the first transparent substrate 101 on the same plane.

When the transparent antenna 100 is incorporated into the electronic device 200, the signal line 121 of the transmission area 120 is electrically connected to the wiring board 250 or the electronic component 260A that is a communication circuit, and is supplied with power P. In FIG. 4 , as an example, the transfer area 120 is shown to have a configuration of about 1/2 from the end on the −Y direction side. In addition, the range of the conveyance area 120 may be about 1/4 - 3/4 of the -Y direction side.

4, an example in which the end of the transfer area 120 extends to the end (-Y side end) of the first transparent substrate 101 is described, but a part or the whole of the transfer area 120 may be located more transparent than the first transparent substrate 101. The peripheral edge of the substrate 101 is further outside. In addition, by flexibly forming the transfer area 120, the transfer area 120 can also be detoured to the side end or the back side of the display module D, and can be electrically connected to the side or back side.

On the other hand, in the second transparent substrate 102 on the lower side of the transparent antenna 100 , the ground region 130 serving as the second thin metal wire layer is provided in the vicinity of the center in the longitudinal direction of the second transparent substrate 102 to the +Y side.

The grounding region 130 provided on the second transparent substrate 102 is not limited to the configurations shown in FIGS. 4 and 5 , and the grounding region 130 may be configured as follows: in the longitudinal direction (±Y direction) of the substrate 102 , the The entire area of the chip element 112 overlaps with at least a part of the ground portions 122 and 123 of the transfer area 120 in a plan view. In addition, the ground region 130 provided on the second transparent substrate 102 may be configured as follows: in the short-side direction (±X direction), the entire region of the planar chip element 112 and the ground portions 122 and 123 of the transfer region 120 At least a part overlaps in plan view. Alternatively, the ground region 130 may be provided on the entire surface on the -Z side of the second transparent substrate 102 .

Here, the ground region 130 provided on the second transparent substrate 102 is not connected to the first transparent substrate 101 by wiring, but the ground region 130 is desirably shared with the ground portions 122 and 123 of the transfer region 120 of the first transparent substrate 101 in AC communication. . Therefore, the grounding region 130 and the grounding portions 122 and 123 of the transfer region 120 preferably overlap in the Y-direction and form an overlapping portion Ov. In particular, the overlap portion Ov in the Y direction only needs to be 0.25λ ₀₁ or more, and if it is an odd multiple of 0.25λ ₀₁ , the overlapped portion operates as a choke coil, which is more preferable.

In addition, the ground area 130 is preferably on the +Y side, covering at least the entire area of the first line element 111 serving as the patch antenna and the planar patch element 112 , and further, relative to the end of the planar patch element 112 , has It is arranged with a margin of +2.5 mm in the Y direction and 2.5 mm in the X direction.

That is, the ground region 130 is preferably as shown by a dotted line in FIG. 5(D) , where X130 is 7.5 mm or more, and Y130 is 7.5 mm or more.

In FIGS. 4 and 5 , although the first substrate 101 and the second transparent substrate 102 have the same vertical and horizontal dimensions (X101=X102, Y101=Y102) and are all overlapped in the vertical direction, the In the transparent antenna 100 of the present invention, the vertical and horizontal dimensions of the first substrate 101 and the second transparent substrate 102 may be different, and may only be partially overlapped in the vertical direction. In the case where the size or position of the two substrates 101 and 102 is offset, at least in the XY direction, the grounding area 130 of the second substrate 102 overlaps with the patch antenna, that is, the area of the antenna pattern 110, and the grounding area 130 in the Y direction is less than It is sufficient to cover the back side so as to overlap with the ground portions 122 and 123 of the transmission region 120 by 0.25 wavelength or more.

Here, the antenna pattern 110, the transmission area 120, and the ground area 130, which are shown as grids in FIGS. 4 and 5, are formed of the transparent conductors shown in FIG. 6 below.

<Transparent conductor of transparent antenna (metal thin wire layer)> FIG. 6 is an explanatory diagram of the transparent conductor 30 of the transparent antenna 100 of the present invention. The transparent conductor 30 is formed on the outermost surfaces of the first transparent substrate 101 and the second transparent substrate 102, and serves as an example for constituting the antenna pattern 110, the transmission area 120, and the ground area 130 shown in FIGS. 4 and 5. The transparent conductor 30 is a conductor whose light transmittance is higher the harder it is to be confirmed by human eyesight.

Specifically, the transparent conductor 30 is formed as a thin metal wire layer, which is a layer of a grid-like conductive line, as an example, in order to improve light transmittance. As shown in FIG. 6 , in the mesh-shaped metal thin wire layer, a plurality of metal thin wires 31 extending in one direction and a plurality of metal thin wires 32 extending in the other direction are arranged to intersect, and the meshes are left open. The gap (diameter) of the shape is the opening (through hole) 33 .

When the transparent conductor 30 is formed in a grid shape, the openings 33 of the grid can be square or rhombus. When the openings 33 of the grid are formed in a square shape, the eyes of the grid are preferably square, and the design is better. In addition, the openings 33 of the mesh may be randomly shaped according to the self-organization method, thereby suppressing the corrugation. The line widths w31 and w32 of the metal thin wires 31 and 32 constituting the mesh are preferably 1 to 10 μm, and more preferably 1 to 5 μm. In addition, the line spacings (also referred to as apertures and pitches) p31 and p32 between the plurality of thin metal lines 31 and between the plurality of thin metal lines 32 of the grid are preferably 50-500 μm, and more preferably 100-400 μm.

The ratio of the area of the openings 33 in the transparent conductor 30 to the entire mesh, that is, the aperture ratio is preferably 80% or more, and more preferably 90% or more. The larger the aperture ratio of the transparent conductor 30 is, the higher the visible light transmittance of the transparent conductor 30 can be.

When the transparent conductor 30 is formed in a grid shape, the thickness of the transparent conductor 30 may also be 1-40 μm. By forming the transparent conductor 30 in a grid shape, the visible light transmittance can be improved even if the transparent conductor 30 is thick. The thickness of the transparent conductor 30 is more preferably 5 μm or more, and more preferably 8 μm or more. Moreover, the thickness of the transparent conductor 30 is more preferably 30 μm or less, more preferably 20 μm or less, and particularly preferably 15 μm or less.

In addition, in the transparent conductor 30, the conductor thickness t is set smaller than the line widths (conductor widths) w31 and w32 of the mesh-like thin lines. This is because if the aspect ratio exceeds 1, the structure will be unbalanced and easily damaged, and manufacturing will be difficult. Among them, the thicker the conductor thickness t, the smaller the sheet resistance value can be. Therefore, as the efficiency of the antenna, the thicker the conductor thickness t, the better. Therefore, t is preferably smaller than w and as large as possible.

In addition, as the conductor material of the thin metal wires 31 and 32 of the transparent conductor 30, copper is exemplified, and metal materials such as silver, aluminum, chromium, nickel, gold, platinum, tin, and iron can also be used, and are not limited to these materials. .

The antenna pattern 110 , the transmission area 120 and the ground area 130 realized by the transparent conductor 30 are transparent, have high light transmittance and are difficult to be recognized by human eyesight, and can function as conductors. In addition, the transparent conductor 30 constituting the thin metal wire layers has a sheet resistance of, for example, 5 Ω/sq or less, more preferably 1 Ω/sq or less, and more preferably around 0.5 Ω/sq.

Here, as shown in FIG. 3 , the first transparent substrate 101 on the upper side of the transparent antenna 100 is disposed on the surface side of the polarizer 280 . Therefore, the thin metal wire layer constituting the antenna pattern 110 and the transmission area 120 formed on the first transparent substrate 101 is less likely to reflect visible light, and is preferably subjected to blackening treatment. In the blackening treatment, the surface of the thin metal wire is coated with a material including copper oxide (CuO) or copper nitride (CuN). In addition, this processing can be omitted for the thin metal wire layer of the second transparent substrate 102 disposed on the inner surface side of the polarizing plate 280 , that is, the thin metal wire of the ground region 130 .

Here, in general, in a patch antenna, since the back side of the patch antenna is shielded by a ground conductor, it is considered to be stable even if conductors of various surface resistance values are arranged close to the antenna. On the other hand, it is generally considered that the patch antenna ground layer is separated from the layer of the antenna pattern, and the antenna characteristics are improved.

Therefore, the antenna performance was compared and reviewed with respect to whether the transparent antenna including the patch antenna has a ground layer and the distance between the antenna pattern and the ground layer is changed.

<Experimental example 1 (simulation example)> Therefore, the inventors of the present application have performed various simulations on the imitation display module in which the transparent cover 240 and the metal conductor M with resistance are arranged above and below the transparent antenna 100 of the present invention shown in FIG. 4 .

FIG. 7 is an explanatory diagram showing an imitation display module SD sandwiched between a transparent cover and a resistor imitating a display with respect to the transparent antenna of the first configuration example of the present invention. In FIG. 7 , (A) is a schematic cross-sectional view of the imitation display module SD, and (B) is a perspective view of the imitation display module SD.

Specifically, on the lowermost side of the imitation display module SD, the sheet resistivity of the resistor body configured as an imitation display or touch panel is 1 Ω/sq (sometimes also described as ohms per square, Ω/□) The metal conductor M. The fourth adhesive layer 294 is arranged on the metal conductor M. As shown in FIG.

Next, as shown in FIG. 7(A), between the fourth adhesive layer 294 and the third adhesive layer 293, the second transparent substrate 102, which is the lower substrate of the transparent antenna 100, is provided. The third adhesive layer 293 , the polarizing plate 280 , and the second adhesive layer 292 are disposed thereon, and the substrate on the upper side of the transparent antenna 100 , that is, the first transparent substrate 101 is disposed thereon. Next, the first adhesive layer 291 and the transparent cover 240 are arranged on the first transparent substrate 101 .

In order to compare and verify the antenna characteristics of the present invention, the present inventors produced the imitation display module SDx of Comparative Example 1 shown in FIG. 8 , and the imitation display module SDy of Comparative Example 2 shown in FIG. 9 , and simulated the gain. .

FIG. 8 shows (A) a cross-sectional view and (B) a perspective view of an imitation display module SDx including the transparent antenna of Comparative Example 1. FIG.

In the imitation display module SDx of FIG. 8 , compared with the structure of FIG. 7 , the difference is that the second transparent substrate 102 and the fourth adhesive layer 294 are not provided. Therefore, in the dummy display module SDx, the grounding area on the lower side of the shielded antenna pattern 110 is not provided.

FIG. 9 shows (A) a cross-sectional view and (B) a perspective view of an imitation display module SDy including the transparent antenna of Comparative Example 2. FIG.

In the imitation display module SDy of FIG. 9 , compared with the structure of FIG. 7 , the difference is that the second transparent substrate 102 and the fourth adhesive layer 294 are not provided, and the grounding area 190 is provided on the back of the first transparent substrate 101Y. In the transmission region on the upper surface side, the ground portions 122 and 123 are not provided on the upper surface side, and only the signal line 121Y is provided. In addition, the difference is that the position of the polarizing plate 280Y is higher than that of the substrate 101Y of the transparent antenna.

Hereinafter, the gain simulated by the imitation display module SD of FIG. 7 , the imitation display module SDx of Comparative Example 1 of FIG. 8 , and the imitation display module SDy of Comparative Example 2 of FIG. 9 will be described.

When simulating the gain, the dimensions of each part of the transparent antenna 100 of the imitation display module SD of FIG. 7 are: X240: 15mm Y240: 15mm X101: 7.5mm Y101: 10mm X102: 15mm Y102: 12mm L111: 0.5mm X112: 2.5mm Y112: 2.5mm W121: 0.4 mm X120: 5.6mm Y120: 5mm X130: 15mm Y130: 12mm Therefore, the length in the Y direction of the overlap between the ground portions 122 and 123 of the substrate 101 and the ground region 130 of the substrate 102 is 2 mm.

In addition, the size of the transparent conductor 30 , which is the thin metal wire layer constituting the antenna pattern 110 , the transmission area 120 , and the ground area 130 , when the unit is μm, is: Conductor thickness of transparent conductor 30: 2 μm Conductor width w31, w32: 3 μm Line spacing p31, p32: 100 μm (200 μm) The sheet resistance of the transparent conductor is about 0.5 Ω/sq.

In addition, if the thickness of each part of the layer in the imitation display module SD of the present invention shown in FIG. 7 is set as μm, it is: Thickness of transparent cover 240: 500 Thickness of the first adhesive layer 291: 150 Thickness of transparent conductor 30 (110, 120): 2 Thickness of the first transparent substrate 101: 100 Thickness of the second adhesive layer 292: 150 Thickness of polarizer 280: 150 Thickness of the third adhesive layer 293: 150 Thickness of the second transparent substrate 102: 125 Thickness of transparent conductor 30 (130): 2 Thickness of the fourth adhesive layer 294: 150 In particular, the thicknesses of the transparent substrates 101 and 102 were 100 μm and 125 μm, respectively.

Therefore, in this example, the distance dm between the antenna pattern 110 on the upper side of the transparent substrate 101 and the ground region 130 on the lower side of the transparent substrate 102 is 675 μm, and the distance between the substrate 101 where the antenna portion is arranged and the substrate 102 where the background is arranged is 675 μm. The distance ds is 450 μm. In addition, since the surface impedance to which the surface resistance is set is set as a boundary condition, the thickness of the metal conductor M is not set.

Furthermore, the dielectric in the imitation display module SD of the present invention shown in FIG. 7 , that is, the dielectric constants of 24 to 35 GHz of each part of each layer are as follows. Transparent cover 240: 6.7 1st Layer 291: 2.6 First transparent substrate 101: 3.2 2nd Layer 292: 2.6 Polarizer 280: 2.9 3rd Layer 293: 2.6 Second transparent substrate 102: 2.4 4th Layer 294: 2.6

The thickness of each layer in the imitation display module SDx of the comparative example 1 shown in FIG. 8 is the same as that of each layer in SD. The above-mentioned second transparent substrate 102 and the transparent conductor 30 ( 130 ) provided on the second transparent substrate 102 , and the fourth adhesive layer 294 has no thickness. In addition, in this configuration, the metal conductor M functions as a background conductor of the pseudo-patch antenna, and the sheet resistance of the metal conductor M is 1.0 Ω/sq. In this configuration, the distance from the antenna pattern 110 to the metal conductor M is 550 μm. The distance between the substrate 101 on which the antenna portion is provided and the metal conductor M is 450 μm.

The thickness of each layer in the imitation display module SDy of Comparative Example 2 shown in FIG. 9 is the same as that of each layer in SD. The above-mentioned second transparent substrate 102 , and the transparent conductors 30 ( 130 ), And the fourth adhesive layer 294 has no thickness, and a ground region 190 is provided on the back surface of the first transparent substrate 101Y. In addition, in this configuration, the ground region 190 functions as a background conductor of the patch antenna, and the sheet resistance of the ground region 190 is 0.5 Ω/sq. In this configuration example, the distance from the antenna pattern 110 to the ground region 190 is the substrate thickness of the first transparent substrate 101Y, eg, 100 μm.

10 shows the imitation display module SD including the transparent antenna of the present invention of FIG. 7 , the imitation display module SDx including the transparent antenna of the comparative example 1 of FIG. 8 , and the imitation display module of FIG. 9 including the transparent antenna of the comparative example 2 Gain of each frequency in group SDy for electromagnetic field analysis.

In the graph of FIG. 10, if the maximum gain is compared, the maximum gain of the imitation display module SDx of Comparative Example 1 is +2.7 dB, and the maximum gain of the imitation display module SDy of Comparative Example 2 is +0.2 dB, In the imitation display module SD of the present invention, the maximum gain is +3.0 dB.

Furthermore, when the gain of the frequencies before and after the 5G band of 25 to 30 GHz is compared, the gain becomes larger in the order of SD of the present invention>SDx of Comparative Example 1>SDy of Comparative Example 2.

Here, the gain (radiation efficiency) of the patch antenna is determined by the following two points. (1) The farther the distance between the antenna element and the ground conductor, the better (2) The lower the resistance of the background conductor, the better

In Comparative Example 2, since the ground region 190 as the background conductor is close to the same substrate, for the reason of (1), as shown by the dotted line in the graph of FIG. 10, the gain is higher than that of the present invention shown by the solid line Display module SD is lower. Therefore, compared with the case where the background conductor is arranged on the same substrate as the antenna portion, the gain and the maximum gain in the 5G band can be improved by disposing the background conductor on other substrates and increasing the distance between the antenna pattern 110 and the ground region 130 .

On the other hand, in Comparative Example 1, the background conductor is the metal conductor M, and the resistance value of the metal conductor M is larger than that of the ground region 130 composed of the metal thin wire layer. Therefore, even if the distance between the substrates is approximately the same, because (2 ), as shown by the dotted line in FIG. 10 , the gain is lower than that of the display module SD of the present invention shown by the solid line. In this experiment, the resistance of the metal conductor M is shown as 1.0 Ω/sq, but the actual touch panel or display panel may have a higher resistance. Therefore, as shown in the present invention, if a low surface resistance value is provided separately from the metal conductor M and used as the ground area of the background conductor, it is better at the point of gain of the patch antenna.

In this way, according to the comparison between Comparative Example 1 and Comparative Example 2 shown in the graph of FIG. 10, the ground layer is provided separately from the metal conductor, and this layer is a dedicated substrate separated from the substrate on which the antenna pattern is formed. In the constitution of the invention, the antenna characteristics of the patch antenna are improved.

<Experimental example 2> FIG. 11 is a schematic view of an experiment showing whether or not the second transparent substrate 102 of the transparent antenna is connected to the ground of the frame. FIG. 12 is a table showing the SN ratio of the touch panel in the case where the second transparent substrate of FIG. 11 is connected to the frame body and the case where there is no connection (floating).

In FIG. 12 , the first column shows the state in which the second transparent substrate without grids is arranged on the touch panel, and the second to fifth columns show the arrangement of the second transparent substrates with grids constituting the metal thin line layer arranged. state on the touch panel. In the left column of the table of FIG. 12 , the types of the meshes constituting the thin metal wire layer, which is the transparent conductor shown in FIG. 6 , are shown. As the type of grid, two grids of grid line width w=4 μm, grid line interval (pitch) p=120 μm, and grid line width w=4 μm and pitch p=60 μm were used. The center column shows whether or not the second transparent substrate shown in FIG. 11 is connected to the grounding portion of the frame. The right column shows the SN ratio of the touch panel under the transparent antenna when the finger moves on the uppermost surface as shown in FIG. 11 . In addition, there is no situation in the left column, which means that the transparent antenna is not arranged on the touch panel.

Comparing rows 2 and 4 with rows 3 and 5 in FIG. 12 , it can be seen that when either grid is used as a transparent conductor, the SN ratio in the floating state decreases from the structure shown in row 1 without a transparent antenna. All are small. In addition, comparing the second and third columns with the fourth and fifth columns, it can be seen that the larger the wire spacing p and the larger the opening, the smaller the decrease in the SN ratio tends to be.

<Second configuration example of transparent antenna> Next, the transparent antenna 100A according to the second configuration example of the present invention will be described with reference to FIGS. 13 and 14 .

FIG. 13 is a perspective view of a transparent antenna 100A according to a second configuration example of the present invention. 14 is an explanatory view of the transparent antenna 100A of the second configuration example, (A) is a plan view of the first transparent substrate 101A, and (B) is a bottom view of the first transparent substrate 101A. 14 (C) is a plan view of the second transparent substrate 102, (D) is a bottom view of the second transparent substrate 102. FIG. In addition, as shown in FIG. 1 , when the transparent antenna is arranged along a curve, in FIGS. 13 and 14 , the state before the transparent antenna is bent is also shown as being parallel to the XY plane.

In the transparent antenna 100A of the present configuration example, in the first transparent substrate 101A, the point in which the transmission region 140 is constituted by the microstrip line is different from that in the first configuration example, and the other points are common.

In this configuration example, the transmission part, that is, the transmission area (also referred to as the power supply area) 140 is a microstrip line, and the surface on the +Z side (surface side) extends from the center of the short-side direction (±X direction) of the substrate. The signal line 141 and the surface on the +Z side (back side) are grounded in a specific range from the end on the -Y side to the +Y side over the entire area in the short-side direction. With such a configuration, the transfer region 140 is arranged at the longitudinal direction end portion (the −Y direction side end portion) of the first transparent substrate 101A. The front end in the transmission direction of the signal line 141 for transmitting the signal (power P) is electrically connected to the first line element 111 of the antenna pattern 110 , and the connection point becomes the power supply point FDa.

In this configuration example, the signal line 141 constituting the transfer region 140 is provided on the upper surface side (+Z side) of the first transparent substrate 101A, and the ground portion 142 is provided on the lower surface side (-Z side) of the first transparent substrate 101A . The grounding portion 142 of the microstrip line is used as a grounding area for the transmission area, and is located on the lower side of the portion of the first transparent substrate 101a where the antenna pattern 110 is not provided.

Also, in the second transparent substrate 102 on the lower side of the transparent antenna 100A, as in the first configuration example, the ground region 130 serving as the second thin metal wire layer is provided in the vicinity of the center in the longitudinal direction of the second transparent substrate 102 to + Y side.

The grounding region 130 provided on the second transparent substrate 102 is not limited to the structures shown in FIGS. 13 and 14 , and the grounding region 130 may be configured as follows: in the longitudinal direction (±Y direction), the planar chip element 112 The whole area overlaps with at least a part of the grounding portion 142 of the transmission area 140 in a plan view. In addition, the ground region 130 provided on the second transparent substrate 102 may be configured as follows: in the short-side direction (±X direction), the entire region of the planar chip element 112 and at least a part of the ground portion 142 of the transfer region 140 Overlapping when viewed from above. Alternatively, the ground region 130 may be provided on the entire surface on the -Z side of the second transparent substrate 102 .

Here, the ground region 130 provided on the second transparent substrate 102 is not connected to the first transparent substrate 101A by wiring, but the ground region 130 is desirably shared with the ground portion 142 of the transfer region 140 of the first transparent substrate 101A. Therefore, the overlap portion Ov between the ground region 130 and the ground portion 142 of the transmission region 140 in the Y direction only needs to be 0.25 wavelength (λ ₀₁ ) or more, and if it is an odd multiple of 0.25 wavelength, the overlapped portion serves as a yoke. It is better to move in a circle. From the viewpoint of space saving, the upper limit of the overlap is preferably 2.5 wavelengths or less, more preferably 1 wavelength or less, and still more preferably 0.8 wavelengths or less.

In this invention, the 1st structural example and the 2nd structural example are both a transparent antenna, and it is comprised so that the board|substrate for an antenna pattern and the board|substrate for grounding may be separated from two substrates. Therefore, in order to ensure a specific gain, a transparent antenna can be realized without making the thickness of the transparent antenna itself too thick even in the case where a distance is required between the antenna pattern in the antenna and the ground area on the back of the antenna.

For example, in electronic equipment, where the allowable thickness of a transparent antenna is 100 μm or less, the limit is relatively large, and the thickness of each substrate is reduced by maintaining a specific distance from the antenna pattern and the grounding area on the back of the antenna. In this way, the transparent antenna can be thinned and converged within the constraints of thickness.

The transparent antenna of the exemplary embodiment of the present invention has been described above, but the present invention is not limited to the specific disclosed embodiment, and various changes and modifications can be made without departing from the scope of the patent application.

This international application claims priority based on Japanese Patent Application No. 2020-143919 filed on August 27, 2020, and the entire content of No. 2020-143919 is incorporated herein by reference.

30: Transparent conductor (metal thin wire layer) 31: Metal thin wire 32: Metal thin wire 33: Opening 100: Transparent antenna 100A: Transparent antenna 101: First transparent substrate (first transparent base material) 101A: First transparent substrate (first transparent substrate) 1 Transparent substrate) 101Y: First transparent substrate 102: Second transparent substrate (second transparent substrate) 110: Antenna pattern (antenna portion, patch antenna, transparent conductor, first metal thin wire layer) 111: First line Element 112: Planar chip element 113: Slot part 114: Slot part 120: Transmission area (generating part, power supply area, coplanar transmission path, first metal thin wire layer) 121: Signal line 121Y: Signal line 122: Ground part 123: Ground portion 130: Ground region (transparent conductor, second thin metal wire layer) 140: Transmission region (transmission portion, power supply region, microstrip line, first thin metal wire layer) 141: Signal line 142: Ground portion 190: Ground Area 200: Electronic equipment 210: Housing 211: Open end 212: Receiving part 220: Display panel 230: Touch panel 240: Transparent cover (cover glass) 250: Wiring boards 260A, 260B, 260C, 260D: Electronic parts 270: battery 280: polarizer (dielectric) 280Y: polarizer 291: 1st adhesive layer 292: 2nd adhesive layer (dielectric) 293: 3rd adhesive layer (dielectric) 294: 4th adhesive layer D: Display module d: Substrate thickness dm: Distance between the antenna pattern and the thin metal layer of the ground area ds: Distance between the substrates between the first transparent substrate and the second transparent substrate F: Power supply point FD: Power supply point FDa: Power supply point f1 : Resonance frequency L111: Dimension M: Metal conductor Ov: Overlap P: Electric power p: Line spacing p31, p32: Line spacing SD: Imitation display module SDx: Imitation display module SDy: Imitation display module t: Conductor thickness t1 : Thickness t2: Thickness w31, w32: Line width W121: Dimension X101: Dimension X102: Dimension X112: Length in the second direction of the planar SMD component X120: Dimension X130: Dimension X240: Dimension Y101: Dimension Y102: Dimension Y112: Length in the first direction of the planar patch element Y120: Dimension Y130: Dimension Y240: Dimension ε1: Dielectric constant ε2: Dielectric constant λ ₀₁ : Wavelength Δn: Refractive index difference δ1: Phase difference δ2: Phase difference

FIG. 1 is an overall view showing the position of a transparent antenna in an electronic apparatus equipped with a display. FIG. 2 is a cross-sectional view of the electronic apparatus of FIG. 1 taken along the AA plane. FIG. 3 is a cross-sectional exploded view showing details of the display module. FIG. 4 is a perspective view of a transparent antenna according to a first configuration example of the present invention. 5 is a top view of (A) a first transparent substrate, (B) a bottom view of the first transparent substrate, (C) a top view of the second transparent substrate, and (D) a second transparent antenna of the transparent antenna of the first configuration example Bottom view of transparent substrate. FIG. 6 is an explanatory diagram of the transparent conductor of the transparent antenna of the present invention. 7 is a cross-sectional view and a perspective view (B) of a display-like module sandwiched between a transparent cover and a display-like resistor with respect to the transparent antenna according to the first configuration example of the present invention. FIG. 8 shows (A) a cross-sectional view and (B) a perspective view of an imitation display module including the transparent antenna of Comparative Example 1. FIG. FIG. 9 shows (A) a cross-sectional view and (B) a perspective view of an imitation display module including the transparent antenna of Comparative Example 2. FIG. 10 shows the imitation display module of FIG. 7 including the transparent antenna of the present invention, the imitation display module of FIG. 8 including the transparent antenna of Comparative Example 1, and the imitation display module of FIG. 9 including the transparent antenna of Comparative Example 2 , the graph of the gain at each frequency. FIG. 11 is a schematic diagram showing an experiment of whether or not the second transparent substrate of the transparent antenna is connected to the ground substrate. FIG. 12 is a table showing the SN ratio (Signal to Noise Ratio: Signal to Noise Ratio) of the touch panel of FIG. 11 in a connected state and a non-connected (floating) state. 13 is a perspective view of a transparent antenna according to a second configuration example of the present invention. 14 is a top view of (A) a first transparent substrate, (B) a bottom view of the first transparent substrate, (C) a top view of the second transparent substrate, and (D) a second transparent antenna of the second configuration example Bottom view of transparent substrate.

100: Transparent Antenna

101: First transparent substrate (first transparent base material)

102: Second transparent substrate (second transparent substrate)

110: Antenna pattern (antenna part, patch antenna, transparent conductor, first metal thin wire layer)

111: 1st line element

112: Surface patch components

120: Transmission area (generating part, power supply area, coplanar transmission path, first metal thin wire layer)

121: Signal line

122: Ground

123: Ground

130: Ground area (transparent conductor, second metal thin wire layer)

dm: the distance between the antenna pattern and the metal thin wire layer of the ground area

ds: the distance between the first transparent substrate and the second transparent substrate

FD: power supply point

Claims (16)

A transparent antenna comprising a first transparent base material, a second transparent base material, a first thin metal wire layer on the first transparent base material, and a second thin metal wire layer on the second transparent base material; and The aperture ratio of the first metal thin line layer and the second metal thin line layer is more than 80%; The sheet resistance of the first metal thin wire layer and the second metal thin wire layer is below 5 Ω/sq; The first metal thin wire layer and the second metal thin wire layer are not in direct current conduction; The first transparent substrate and the second transparent substrate are separated by more than 100 μm; The first thin metal wire layer has a patch-shaped antenna portion; The second thin metal wire layer is formed over at least a region including the antenna portion in a plan view. The transparent antenna of claim 1, wherein The first thin metal wire layer is located on the upper side of the first transparent substrate, and the second thin metal wire layer is located on the lower side of the second transparent substrate. The transparent antenna of claim 1 or 2, wherein The retardation δ1 of the first transparent base material at a thickness of 100 μm is 1 or more and 10000 or less, and the retardation δ2 of the second transparent base material at a thickness of 100 μm is 0.1 to 1000, and δ1≧δ2. The transparent antenna of claim 3, wherein The dielectric constant ε1 of the first transparent base material and the dielectric constant ε2 of the second transparent base material are in a relationship of ε1≧ε2. The transparent antenna of claim 3 or 4, wherein The said 1st transparent base material is PET or COP, and the said 2nd transparent base material is COP. The transparent antenna of any one of claims 1 to 5, wherein The first metal thin wire layer has a transmission part, and the transmission part is a coplanar waveguide; The signal line and the ground portion of the coplanar waveguide are disposed on the upper side of the first transparent substrate. The transparent antenna of claim 1, wherein The first metal thin wire layer has a transmission portion; The above-mentioned transmission part is a microstrip line; The signal line of the microstrip line is located on the upper side of the first transparent substrate, and the ground portion of the microstrip line is located on the lower side of the portion of the first transparent substrate where the antenna portion is not provided. The transparent antenna of claim 6 or 7, wherein The grounding portion of the transmission portion of the first thin metal wire layer and the second thin metal wire layer include an overlapping portion in a plan view. The transparent antenna of claim 8, wherein The width of the overlapping portion is 0.25 wavelength or more and 2.5 wavelength or less. A display module comprising: transparent antenna; dielectric; and a display panel; and The above transparent antenna has: a first transparent substrate provided with a first metal thin wire layer, and a second transparent substrate provided with a second metal thin wire layer; and The aperture ratio of the first metal thin line layer and the second metal thin line layer is more than 80%; The sheet resistance of the first metal thin wire layer and the second metal thin wire layer is below 5 Ω/sq; The first metal thin wire layer and the second metal thin wire layer are not in direct current conduction; The first transparent substrate and the second transparent substrate are separated by more than 100 μm; The first thin metal wire layer has a patch-shaped antenna portion; The second thin metal wire layer is formed across at least the region including the antenna portion in plan view; The said dielectric material is provided between the said 1st transparent base material and the said 2nd transparent base material. The display module of claim 10, wherein The dielectric constant ε1 of the first transparent base material and the dielectric constant ε2 of the second transparent base material are in a relationship of ε1≧ε2. The display module of claim 10 or 11, wherein The above-mentioned dielectric is a polarizer. The display module of any one of claims 10 to 12, wherein There is a first conductive layer on the lower side of the second transparent substrate of the transparent antenna; and The sheet resistance of the first conductive layer is 5 Ω/sq to 20 Ω/sq. The display module of claim 13, wherein The above-mentioned first conductive layer has a function as a touch panel provided on the above-mentioned display panel, or a cathode of an OLED display panel constituting the above-mentioned display panel. The display module of claim 13 or 14, wherein The first conductive layer and the second thin metal wire layer of the transparent antenna are not in direct current conduction with each other. The display module of any one of claims 13 to 15, wherein The said 1st conductive layer and the said 2nd thin metal wire layer of the said transparent antenna contain the area|region which does not overlap in planar view.

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