Antenna Device

Abstract

Provided is an antenna device including a transparent antenna element that can be arranged in a position visible from outside a transparent cover of an electronic instrument.　The antenna device includes: a transparent flexible substrate provided on an inner-surface side that is opposite the outer surface of the transparent cover, which is made from glass or resin, of the electronic instrument; and the transparent antenna element, which is provided at a position in the flexible substrate that is visible from outside the transparent cover, the transparent antenna element having directionality facing outside the electronic instrument.

Description

[Technical field]

[0001] The present invention relates to an antenna device. [Background technology]

[0002] Conventionally, there has been an antenna device for use in electronic devices such as smartphones, which comprises a ground plane, a plate-shaped conductor having a portion facing the ground plane with a gap therebetween, a feed element connected to a feed point with the ground plane as a ground reference, and a linear radiating element connected to the plate-shaped conductor, and the radiating element is fed with power by the feed element in a non-contact manner and functions as a radiating conductor (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 203976 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if a conventional antenna device is placed in a position visible from the outside of a transparent cover of an electronic device, it will obstruct the display of the display panel, and therefore is not suitable for placement in a position visible from the outside of the transparent cover.

[0005] Therefore, an object of the present invention is to provide an antenna device including a transparent antenna element that can be arranged in a position visible from the outside of a transparent cover of an electronic device. [Means for solving the problem]

[0006] An antenna device according to an embodiment of the present invention includes a transparent flexible substrate provided on the inner surface opposite to the outer surface of a glass or resin transparent cover of an electronic device, and a transparent antenna element provided on the flexible substrate in a position visible from the outside of the transparent cover and having directionality facing toward the outside of the electronic device. Effect of the Invention

[0007] It is possible to provide an antenna device including a transparent antenna element that can be arranged in a position visible from the outside of a transparent cover of an electronic device. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing an example of a cross section of an electronic device 200 including an antenna device 100. FIG. [Diagram 2] 2 is an enlarged view of a part of a cross section of electronic device 200. FIG. [Diagram 3] 2 is an enlarged view of the dotted line portion A in FIG. 1. [Figure 4] 1 is a diagram illustrating an antenna device 100. [Diagram 5] 1 is a diagram illustrating an antenna device 100. [Figure 6] FIG. 2 is a diagram showing a transparent conductor 300A. [Figure 7] 1 is a diagram showing a waveguide 300B formed in a substrate 101. FIG. [Figure 8] 11 is a diagram illustrating frequency characteristics of the S11 parameter of the antenna device 100. FIG. [Figure 9] Illustrated is the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100 set to 28 GHz. [Figure 10] 1 is a diagram illustrating the directivity of the antenna device 100 on an exemplary cross section of the electronic device 200. FIG. [Figure 11] FIG. 11 is a cross-sectional view showing an electronic device 200A according to a modified example of the embodiment. [Figure 12] FIG. 2 is a diagram showing an antenna device 100M1. [Figure 13]FIG. 2 is a diagram showing an antenna device 100M1. [Figure 14] FIG. 13 is a diagram showing frequency characteristics of the S11 parameter of the antenna device 100M1. [Figure 15] 13 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M1 set to 28 GHz. [Figure 16] FIG. 2 is a diagram showing an antenna device 100M2. [Figure 17] FIG. 2 is a diagram showing an antenna device 100M2. [Figure 18] 13 is a diagram showing the relationship between the number of directors 115, the spacing G, and the directivity and gain. FIG. [Figure 19] 13 is a diagram showing frequency characteristics of the S11 parameter of an antenna device 100M2 having one director 115 with a gap G set to 4 mm. [Figure 20] 13 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of an antenna device 100M2 having one director 115 with a spacing G of 4 mm set to 28 GHz. [Figure 21] 13 is a diagram showing frequency characteristics of the S11 parameter of an antenna device 100M2 in which five directors 115 are set at intervals G of 1 mm. [Figure 22] 13 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of antenna device 100M2, which has five directors 115 set at intervals G of 1 mm, set to 28 GHz. [Figure 23] 13 is a diagram illustrating the directivity of an antenna device 100M2 on an exemplary cross section of an electronic device 200A. [Figure 24] FIG. 11 is a cross-sectional view showing an electronic device 200B according to a modified example of the embodiment. [Diagram 25] FIG. 1 illustrates an antenna device 100M2. [Figure 26] 11A to 11C are diagrams illustrating a method for bending the antenna device 100M2. [Figure 27] 11 is a diagram showing a bending model of the antenna device 100M2. FIG. [Figure 28]13A and 13B are diagrams illustrating the directivities of an antenna device 100M2 that is bent at different positions. [Figure 29] FIG. 13 is a diagram showing an antenna device 100M3 according to a modified example of the embodiment. [Diagram 30] FIG. 1 is a diagram showing a model of an antenna device 100M3. [Diagram 31] FIG. 13 is a diagram showing frequency characteristics of the S11 parameter of the antenna device 100M3 bent at the position Z=1 mm. [Diagram 32] 13 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M3 bent at the position Z=1 mm set to 28 GHz. [Diagram 33] FIG. 1 is a diagram showing an antenna device 100M4. [Diagram 34] FIG. 1 is a diagram showing an antenna device 100M4. [Diagram 35] 13 is a diagram showing frequency characteristics of the S11 parameter of an antenna device 100M4 for Sub6 which has one director 115. FIG. [Diagram 36] 13 is a diagram showing the directivity obtained by an electromagnetic field simulation performed by setting the resonant frequency of an antenna device 100M4 for Sub6 having one director 115 to 3.5 GHz. [Figure 37] FIG. 13 is a diagram showing an electronic device 200C according to a modified example of the embodiment. [Figure 38] FIG. 13 is a diagram showing an electronic device 200D according to a modified example of the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment to which the antenna device of the present invention is applied will be described.

[0010] <Embodiment Mode> Fig. 1 is a diagram showing an example of a cross section of electronic device 200 including antenna device 100. Fig. 2 is a diagram showing an enlarged portion of the cross section of electronic device 200. In the following, an XYZ coordinate system is defined and described. For convenience of explanation, a plan view in the following refers to a YZ plane view, and a description is given using a vertical direction with +X direction side as the upper side and -X direction side as the lower side, and a horizontal direction (side) with respect to the vertical direction, but these do not represent universal vertical and horizontal directions.

[0011] In addition, in the directions of parallel, right-angled, orthogonal, horizontal, vertical, up-down, left-right, etc., deviations that do not impair the effects of the disclosure in the embodiments are permitted. In addition, the X direction, Y direction, and Z direction respectively represent directions parallel to the X axis, the Y axis, and the Z axis. The X direction, the Y direction, and the Z direction are perpendicular to each other. The XY plane, the YZ plane, and the ZX plane respectively represent imaginary planes parallel to the X direction and the Y direction, imaginary planes parallel to the Y direction and the Z direction, and imaginary planes parallel to the Z direction and the X direction.

[0012] In the following description, the same reference numerals may be used to designate substantially the same components, and redundant explanations may be omitted.

[0013] The antenna device 100 is suitable for transmitting and receiving radio waves in a high frequency band (for example, more than 1 GHz to 300 GHz) such as microwaves and millimeter waves. The antenna device 100 is applicable to, for example, a fifth generation mobile communication system (5G) or a sixth generation mobile communication system (6G), but is not limited to these. The fifth generation mobile communication system (5G) includes, for example, the 28 GHz band and a band below 6 GHz (Sub 6).

[0014] 1 and 2 show a portion 100A and a portion 100B of the antenna device 100. The portion 100A is an example of a first portion, and the portion 100B is an example of a second portion of the antenna device 100. To make the positions of the portions 100A and 100B easier to understand, the portion 100A is shown in white, and the portion 100B is shown in gray.

[0015] Although the detailed configuration of the antenna device 100 will be described later, the antenna device 100 has, for example, a flexible substrate, an antenna element, and a feed line, and is bendable. In Fig. 1 and Fig. 2, the antenna device 100 is bent so as to be folded between the portion 100A and the portion 100B. Moreover, the portion 100B is further bent inside the storage section 210B.

[0016] Portion 100A is a portion on the flexible substrate where at least an antenna element is provided, and may be provided with a portion of a feed line in addition to the antenna element. Portion 100B is a portion on the flexible substrate where at least a portion of the feed line (the entire feed line, or the remaining portion of the feed line that is not provided in portion 100A) is provided.

[0017] Part 100A of antenna device 100 is disposed on the upper side (display surface side) of a display panel included in display operation unit 230. Part 100A of antenna device 100 is transparent since it is visible from outside electronic device 200 through transparent cover 220. Part 100B is disposed on the back side of display operation unit 230 and is not visible from outside electronic device 200, so it does not have to be transparent.

[0018] 1 and 2, for convenience of explanation, the portion 100A of the antenna device 100 is shown between the transparent cover 220 and the display operation unit 230, but the portion 100A of the antenna device 100 is not limited to being between the display operation unit 230 and the transparent cover 220, and may be disposed anywhere between the touch panel, the polarizing plate, and the display panel included in the display operation unit 230. The positional relationship between the portion 100A of the antenna device 100, the transparent cover 220, and the display operation unit 230 will be described later.

[0019] Moreover, the antenna device 100 has a directivity that faces the outside of the electronic device 200. The directivity of the antenna device 100 is the directivity of the main lobe. The directivity facing outward means that the directivity of the main lobe of the antenna device 100 faces the outside of the housing 210 and the transparent cover 220 of the electronic device 200. Facing outward means, for example, facing in the +X direction of the transparent cover 220, a direction parallel to the YZ plane outside the transparent cover 220, or a direction between the +X direction of the transparent cover 220 and a direction parallel to the YZ plane outside the transparent cover 220, when viewed from inside the electronic device 200. Furthermore, when a part of the housing 210 has a dielectric part, the antenna device 100 may face the outside of the housing 210 through the dielectric part.

[0020] The electronic device 200 is, for example, an information processing terminal such as a smartphone, a tablet computer, a notebook PC (Personal Computer), etc. In addition, the electronic device 200 is not limited to these, and may be, for example, a structure such as a pillar or a wall, a digital signage, an electronic device including a display panel in a train, or an electronic device including various display panels in a vehicle.

[0021] In addition to the antenna device 100, the electronic device 200 includes a housing 210, a transparent cover 220, a display operation unit 230, a wiring board 240, electronic components 250A and 250B, and a battery 260. The display operation unit 230 has a display panel. In this manner, the electronic device 200 may be any electronic device including the housing 210, the transparent cover 220, and the display panel.

[0022] Housing 210 is, for example, a case made of metal and / or resin, and covers the bottom and side surfaces of electronic device 200. Housing 210 has opening 210A on the upper side, and transparent cover 220 is attached to opening 210A. Housing 210 has storage section 210B, which is an internal space communicating with opening 210A, and storage section 210B stores wiring board 240, electronic components 250A and 250B, battery 260, etc.

[0023] The transparent cover 220 is a transparent glass plate having a rectangular shape in a plan view, and has a size that matches the opening 210A in a plan view. The transparent cover 220 is, for example, a flat glass plate. Here, a form in which the transparent cover 220 is made of glass will be described, but the transparent cover 220 may be made of resin.

[0024] Transparent cover 220 is attached to opening 210A of housing 210, thereby sealing storage section 210B of housing 210.

[0025] The upper surface of transparent cover 220 is an example of an outer surface of transparent cover 220, and the lower surface of transparent cover 220 is an example of an inner surface of transparent cover 220. Display operation unit 230 is provided on the inner surface side of transparent cover 220. Display operation unit 230 provided inside can be seen from the outside of electronic device 200 through transparent cover 220.

[0026] Display operation unit 230 is a component in which a touch panel, a polarizing plate, a display panel, etc. are layered. In electronic device 200, the user can operate buttons and the like of a GUI (Graphical User Interface) displayed on the display panel of display operation unit 230 by touching the top surface of transparent cover 220. The user's operation is detected by the touch panel of display operation unit 230.

[0027] A display panel is disposed on the lowermost side of the display operation unit 230. In a portion where the antenna device 100 is not present, a touch panel and a polarizing plate are superimposed on the display panel. Either the touch panel or the polarizing plate may be on top. In a portion where the antenna device 100 is present, the antenna device 100 is provided somewhere above the display panel.

[0028] Electronic components 250A and 250B are mounted on wiring board 240. A power feed line and the like of portion 100B of antenna device 100 are connected to wiring board 240. Wiring board 240 and portion 100B may be connected using a connector, an ACF (Anisotropic Conductive Film), or the like, or may be connected using other components.

[0029] As an example, electronic component 250A is a component that performs information processing related to the operation of electronic device 200, and is realized by a computer including, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a HDD (Hard Disk Drive), an input / output interface, and an internal bus.

[0030] The electronic component 250B is connected to the portion 100B of the antenna device 100 via wiring on the wiring board 240, and is a communication module that processes signals transmitted or received via the antenna device 100, for example.

[0031] The battery 260 is a rechargeable secondary battery, and supplies the power required for the operation of the antenna device 100, the display operation unit 230, the electronic components 250A and 250B, and the like.

[0032] Next, a description will be given of the positional relationship between the antenna device 100 and the display / operation unit 230. Fig. 3 is an enlarged view of the dotted line part A in Fig. 1.

[0033] The display operation unit 230 has a display panel 231, a layer 232, a layer 233, and an adhesive layer 234. The adhesive layer 234 is a layer made of an adhesive material provided for adhering the display operation unit 230 to the transparent cover 220.

[0034] The display panel 231 is, for example, a liquid crystal display panel, an organic EL (Electro-luminescence) or an OLED (Organic Light Emitting Diode) display panel, and is disposed at the bottom of the display operation unit 230.

[0035] The layers 232 and 233 each include at least a touch panel, a polarizing plate, and a plurality of adhesive layers. In some cases, the layer 232 includes a touch panel and an adhesive layer, and the layer 233 includes a polarizing plate and an adhesive layer. In other cases, the layer 232 includes a polarizing plate and an adhesive layer, and the layer 233 includes a touch panel and an adhesive layer.

[0036] In FIG. 3, as an example, portion 100A of antenna device 100 is shown between layers 232 and 233, but portion 100A may also be disposed between layer 233 and adhesive layer 234, or between layer 232 and display panel 231.

[0037] In addition, in a position where the portion 100A of the antenna device 100 is not present, the cross-sectional structure of the transparent cover 220 and the display / operation unit 230 is the same as that in FIG. 3 with the portion 100A of the antenna device 100 removed.

[0038] Figures 4 and 5 are diagrams showing the antenna device 100. Figures 4 and 5 show the antenna device 100 parallel to the YZ plane before the portion 100B is folded as shown in Figures 1 and 2.

[0039] The antenna device 100 includes a substrate 101, an antenna element 110, and a microstrip line 120. Fig. 5(A) shows the substrate 101 and components arranged on the surface of the substrate 101 in the +X direction, and Fig. 5(B) shows the components arranged on the surface of the substrate 101 in the +X direction. Note that in Fig. 5(B), the position of the substrate 101 is indicated by a dashed line.

[0040] The portion of microstrip line 120 included in portion 100A is, for example, about 1 / 2 to 3 / 4 on the +Z direction side of the entire microstrip line 120 in the Z direction. Therefore, the portion of microstrip line 120 included in portion 100B is, for example, about 1 / 4 to 1 / 2 of the entire microstrip line 120 in the Z direction.

[0041] 1 and 2 is located at a position about 1 / 2 to 3 / 4 from the end of the microstrip line 120 on the +Z direction side in the Z direction. Since the part 100B is located on the display panel 231 shown in Fig. 3, it is sufficient that the part 100B is transparent so as not to interfere with the display. The part 100B does not have to be transparent.

[0042] 4 and 5 show, as an example, a configuration in which the boundary between the portion 100A and the portion 100B is 1 / 2 of the way from the end of the microstrip line 120 on the +Z direction side in the Z direction.

[0043] The substrate 101 is, for example, a flexible substrate made of polyimide, and is bendable in the Z direction and / or the Y direction. The substrate 101 is colorless and transparent.

[0044] Antenna element 110 is a dipole antenna and has elements 111 and 112. Element 111 is provided on the surface of substrate 101 on the +X direction side, and is an L-shaped element having a feed point 111A, a bent portion 111B, and an open end 111C. Element 111 extends in the +Z direction from feed point 111A toward bent portion 111B, is bent in the +Y direction at bent portion 111B, and extends to open end 111C.

[0045] The element 112 is provided on the surface of the substrate 101 in the -X direction, and is an L-shaped element having a feed point 112A, a bent portion 112B, and an open end 112C. The section between the feed point 112A and the bent portion 112B is arranged to overlap the section between the feed point 112A and the bent portion 112B of the element 111 in a plan view, and the section between the bent portion 112B and the open end 112C extends in the -Y direction in the opposite direction to the section between the bent portion 111B and the open end 111C of the element 111. The length in the Y direction between the open ends 111C and 112C is set to about 1 / 2 (λe / 2) of the electrical length λe of the wavelength λ at the resonant frequency of the antenna device 100.

[0046] The microstrip line 120 is a feed line having a transmission line 121 and a ground layer 122. The transmission line 121 is provided on the surface of the substrate 101 on the +X direction side, and is connected to a feed point 111A of the element 111.

[0047] The ground layer 122 is provided on the surface on the −X direction side of the substrate 101 so as to overlap the transmission line 121 in a plan view. An end side of the ground layer 122 on the +Z direction side is connected to the feeding point 112A of the element 112.

[0048] In the antenna device 100 having such a configuration, the section in the Z direction where the antenna element 110 and the portion of the microstrip line 120 on the +Z direction side are provided is the portion 100A shown in Figures 1 and 2. In addition, in the antenna device 100, the section in the Z direction where the remaining portion of the microstrip line 120 is provided is the portion 100B shown in Figures 1 and 2.

[0049] Since the antenna device 100 is bent between the portion 100A and the portion 100B shown in Figures 1 and 2, the substrate 101 of the antenna device 100 is bent between the tip side of the antenna element 110 and the end of the ground layer 122 that is farther from the antenna element 110.

[0050] Fig. 6 is a diagram showing a transparent conductor 300A. The transparent conductor 300A is formed on the surface of a transparent substrate 101, and is used, for example, as the antenna element 110 and the microstrip line 120 included in the portion 100A shown in Fig. 4 and Fig. 5. The transparent conductor 300A is a conductor with such high optical transparency that it is difficult for the human eye to see it.

[0051] The transparent conductor 300A is, for example, a conductive line formed in a mesh shape to enhance light transmittance, where "mesh" refers to a state in which the transparent conductor 300A has a network of through holes 301.

[0052] When the transparent conductor 300A is formed in a mesh shape, the mesh may be rectangular or rhombic. When the mesh is formed in a rectangular shape, the mesh is preferably square, which provides good design. The mesh may also be randomly shaped by a self-organizing method, which can suppress moire. The mesh line widths w1 and w2 are preferably 1 to 10 μm. The mesh line spacing p1 and p2 are preferably 300 to 500 μm.

[0053] The aperture ratio of the transparent conductor 300A is preferably 80% or more, and more preferably 90% or more. The aperture ratio is the ratio of the area of ​​the openings to the area including the openings (through holes 301) of the transparent conductor 300A. The larger the aperture ratio of the transparent conductor 300A, the higher the visible light transmittance of the transparent conductor 300A can be.

[0054] The thickness of the transparent conductor 300A is preferably 400 nm or less, more preferably 300 nm or less, in order to increase the visible light transmittance. The lower limit of the thickness of the transparent conductor 300A is not particularly limited, but may be 2 nm or more, 10 nm or more, or 30 nm or more in order to improve the radiation characteristics.

[0055] Furthermore, when the transparent conductor 300A is formed in a mesh shape, the thickness of the transparent conductor 300A may be 1 to 40 μm. By forming the transparent conductor 300A in a mesh shape, the visible light transmittance can be increased even if the transparent conductor 300A is thick. The thickness of the transparent conductor 300A is more preferably 5 μm or more, and even more preferably 8 μm or more. The thickness of the transparent conductor 300A is more preferably 30 μm or less, even more preferably 20 μm or less, and particularly preferably 15 μm or less.

[0056] The conductive material of the transparent conductor 300A may be copper, but may also be other metals such as gold, silver, platinum, aluminum, and chromium, and is not limited to these materials.

[0057] Since the portion 100A of the antenna device 100 is located above the display panel 231 (see FIG. 3), the conductors (antenna element 110, microstrip line 120, etc.) included in the portion 100A may be realized by, for example, a transparent conductor 300A.

[0058] The antenna element 110 and a portion of the microstrip line 120 realized by the transparent conductor 300A are transparent, and are an antenna element and a feed line that are so light-transmitting that they are difficult to see with human eyesight.

[0059] Furthermore, the remaining portion of the microstrip line 120 included in the portion 100B of the antenna device 100 is located behind the display panel 231 (see FIG. 3), and therefore does not need to be transparent and may be a solid pattern (solid pattern) of copper or the like.

[0060] For the remaining portion of the microstrip line 120 included in the portion 100B, a waveguide 300B as shown in Fig. 7 may be used. Fig. 7 is a diagram showing the waveguide 300B formed on the substrate 101. Fig. 7(A) shows the waveguide 300B in a plan view, and Fig. 7(B) shows a cross section taken along the line AA in Fig. 7(A). Note that in Fig. 7, an XYZ coordinate system is defined as shown in the figure as an example.

[0061] The waveguide 300B is formed on the substrate 101, and includes conductive layers 301B and 302B, and a through hole (TH) 303B. The waveguide 300B is a so-called substrate integrated waveguide (SIW) that includes conductive layers 301B and 302B provided on both sides of the single-layer substrate 101, and the TH 303B.

[0062] The conductive layers 301B and 302B are solid patterns (solid patterns) formed in partial regions of the surface on the -X direction side and the surface on the +X direction side of the substrate 101. The conductive layers 301B and 302B have the same size in a plan view, and are provided on both sides of the substrate 101 while being aligned with each other.

[0063] TH303B is a columnar or cylindrical conductor formed by plating or the like on the inside of a through hole penetrating the substrate 101 in the X direction. TH303B connects the conductive layers 301B and 302B. TH303B are provided at equal intervals on both sides of the conductive layers 301B and 302B along the propagation direction of the radio wave (here, +Z direction as an example). The gap between adjacent TH303B in the Z direction is set to be less than the wavelength of the propagating radio wave. This makes it possible to shield the space surrounded by the conductive layers 301B and 302B and TH303B.

[0064] The space surrounded by such conductive layers 301B and 302B and the TH 303B is a shielded transmission path, and can confine radio waves and propagate them in the Z direction. Such a waveguide 300B may be used as a feed line in the portion 100B of the antenna device 100 (see FIGS. 1 and 2) in place of the remaining portion of the microstrip line 120.

[0065] Fig. 8 is a diagram showing frequency characteristics of the S11 parameter of the antenna device 100. Fig. 8 shows frequency characteristics of the S11 parameter obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100 set to 28 GHz. Good characteristics were obtained in which the S11 parameter was -5 dB or less over a wide range around 28 GHz.

[0066] Fig. 9 shows the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of antenna device 100 set to 28 GHz. The directivity shown in Fig. 9 is the directivity of the main lobe of antenna device 100. The 0 degree direction corresponds to the +Z direction, and the 90 degree direction corresponds to the +X direction. As shown in Fig. 9, it can be seen that directivity in the +Z direction (0 degree direction) is obtained.

[0067] 10 is a diagram showing the directivity of the antenna device 100 on an exemplary cross section of the electronic device 200. The directivity shown in FIG. 9 indicates that radio waves can be emitted in the direction indicated by (1) in FIG. 10, and that radio waves can be received in the direction indicated by (1). The direction indicated by (1) is the direction of radiation from the surface of the transparent cover 220 of the electronic device 200 (the surface of the electronic device 200) along the surface of the transparent cover 220. Since the antenna device 100 has directivity in such a direction (1), it is easy for the antenna device 100 to communicate with a communication device outside the electronic device 200.

[0068] As described above, the antenna device 100 has a configuration in which the transparent antenna element 110 is provided on the transparent substrate 101. The transparent antenna element 110 is provided at a position visible from the outside of the transparent cover 220, and is provided overlapping the display panel 231 (see FIG. 3).

[0069] Therefore, an antenna device 100 can be provided that includes a transparent antenna element 110 that can be positioned in a position visible from the outside of the transparent cover 220 of the electronic device 200, a transparent portion included in portion 100A of the microstrip line 120, and a transparent substrate 101.

[0070] Furthermore, the dipole-type antenna element 110 and the microstrip line 120 can be formed very thin. For example, if the allowable thickness of the antenna device 100 is highly restricted, such as 100 μm or less, it is difficult to use an antenna device that requires a certain degree of thickness in the ground layer, such as a patch antenna. In this respect, the antenna device 100 including the dipole-type antenna element 110 and the microstrip line 120, which can be formed very thin, is very advantageous in terms of thinning.

[0071] In the above, the transparent cover 220 of the electronic device 200 is described as being flat, but the transparent cover 220 may be curved.

[0072] Moreover, in the above description, the antenna element 110 is a dipole antenna, but it may be a monopole antenna, a tapered slot antenna, a slot antenna, or a log periodic antenna.

[0073] Furthermore, the antenna device 100 may further include one or more parasitic elements fed via the antenna element 110. In this case, directivity facing outward from the electronic device 200 may be realized by adjusting the positional relationship between the antenna element 110 and the one or more parasitic elements.

[0074] Fig. 11 is a cross-sectional view showing electronic device 200A according to a modified example of the embodiment. Fig. 11 shows a cross-section corresponding to Fig. 1. Electronic device 200A includes transparent cover 220A and display operation unit 230A with curved ends in a plan view, instead of flat transparent cover 220 and display operation unit 230 of electronic device 200 shown in Fig. 1. To make the positions of part 100A and part 100B easier to understand, part 100A is shown in white and part 100B is shown in gray.

[0075] In the XZ cross section, both ends of the transparent cover 220 in the Z direction are curved in the -X direction. This is the same in the YZ cross section. The display operation unit 230A includes an OLED as a display panel, for example, and has a curved shape similar to that of the transparent cover 220A.

[0076] In FIG. 11, a portion 100A of the antenna device 100 is provided across the flat upper surface portion and the curved portion of the transparent cover 220A.

[0077] In Figure 11, for ease of explanation, part 100A of antenna device 100 is shown between transparent cover 220A and display operation unit 230A, but part 100A of antenna device 100 is not limited to being disposed between display operation unit 230A and transparent cover 220A, and may be disposed between layers 232 and 233 shown in Figure 3, between layer 233 and adhesive layer 234, or between layer 232 and display panel 231.

[0078] Moreover, the electronic device 200 or 200A may include an antenna device 100M1 shown in Figures 12 and 13, instead of the antenna device 100 shown in Figures 4 and 5. Figures 12 and 13 are diagrams showing the antenna device 100M1.

[0079] 12 and 13 are diagrams showing the antenna device 100M1. In FIG. 12 and FIG. 13, the antenna device 100M1 before bending is shown parallel to the YZ plane. The antenna device 100M1 includes portions 100M1A and 100M1B. The portions 100M1A and 100M1B are similar to the portions 100A and 100B shown in FIG. 1, FIG. 2, FIG. 4, and FIG. 5. The portion 100M1A is a portion that can be seen from the outside of the electronic device 200 or 200A through the transparent cover 220 or 220A of the electronic device 200 or 200A, and the portion 100M1B is a portion that is arranged on the back side of the display operation unit 230 or 230A and cannot be seen from the outside of the electronic device 200 or 200A.

[0080] 12 and 13 show, as an example, a configuration in which the boundary between the portion 100M1A and the portion 100M1B is 1 / 2 of the way from the end of the microstrip line 120M1 on the +Z direction side in the Z direction.

[0081] The antenna device 100M1 includes a substrate 101, an antenna element 110M1, and a microstrip line 120M1. Fig. 13(A) shows the substrate 101 and components arranged on the surface of the substrate 101 in the +X direction, and Fig. 13(B) shows the components arranged on the surface of the substrate 101 in the +X direction. Note that in Fig. 13(B), the position of the substrate 101 is indicated by a dashed line.

[0082] The antenna element 110M1 is a Vivaldi type antenna and includes elements 111M1 and 112M1. The antenna element 110M1 is realized by a transparent conductor 300A (see FIG. 6).

[0083] The element 111M1 is provided on the surface on the +X direction side of the substrate 101, and has a feed point 111M1A and an open end 111M1C. The element 111M1 extends from the feed point 111M1A to the open end 111M1C.

[0084] Element 112M1 is provided on the surface of substrate 101 on the -X direction side, and has feed point 112M1A and open end 112M1C. Feed point 112M1A is arranged to overlap feed point 111M1A of element 111M1 in a planar view. The shape, size, and position of element 112M1 relative to substrate 101 when viewed from the -X direction are equal to the shape, size, and position of element 111M1 relative to substrate 101 when viewed from the +X direction.

[0085] The microstrip line 120M1 has transmission lines 121M1A and 121M1B and ground layers 122M1A and 122M1B. The transmission lines 121M1A and 121M1B are provided on the surface of the substrate 101 in the +X direction. The transmission line 121M1A is provided overlapping the ground layer 122M1A. The transmission line 121M1B is connected to the +Z direction side of the transmission line 121M1A, is provided overlapping the ground layer 122M1B, and is connected to the feeding point 111M1A of the element 111M1.

[0086] The ground layer 122M1A is a rectangular ground pattern provided on the surface of the substrate 101 on the -X direction side so as to overlap the transmission line 121M1A in a plan view. The ground layer 122M1B is formed continuously on the +Z direction side of the ground layer 122M1A, and the width in the Y direction gradually narrows toward the +Z direction side. The end of the ground layer 122M1B on the +Z direction side is located at the center of the substrate 101 in the Y direction, and the width in the Y direction of the end of the ground layer 122M1B on the +Z direction side is equal to the width in the Y direction of the power feed point 112M1A of the element 112M1. The end of the ground layer 122M1B on the +Z direction side is connected to the power feed point 112M1A of the element 112M1.

[0087] In the antenna device 100M1 having such a configuration, the portion where the antenna element 110M1 and a part of the microstrip line 120M1 on the +Z direction side are provided in the Z direction is the portion 100A shown in Figures 1 and 2. In addition, in the antenna device 100M1, the section where the remaining portion of the microstrip line 120M1 is provided is the portion 100B shown in Figures 1 and 2. Since the portion 100A is located above the display panel 231 shown in Figure 3, it is sufficient that it is transparent so as not to interfere with the display.

[0088] Fig. 14 is a diagram showing frequency characteristics of the S11 parameter of the antenna device 100M1. Fig. 14 shows frequency characteristics of the S11 parameter obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M1 set to 28 GHz. A good band was obtained in which the S11 parameter was -5 dB or less around 28 GHz. Note that the band of -5 dB or less around 41 GHz was generated unintentionally.

[0089] Fig. 15 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M1 set to 28 GHz. The directivity shown in Fig. 15 is the directivity of the main lobe of the antenna device 100M1. The 0 degree direction corresponds to the +Z direction, and the 90 degree direction corresponds to the +X direction. As shown in Fig. 15, it can be seen that directivity in the +Z direction (0 degree direction) is obtained.

[0090] It is considered that the directivity when the antenna device 100M1 is attached to the electronic device 200 will be substantially similar to the directivity when the antenna device 100 is attached to the electronic device 200 as shown in FIG.

[0091] Similar to the antenna device 100, the antenna device 100M1 has a configuration in which a transparent antenna element 110M1 is provided on a transparent substrate 101. The transparent antenna element 110M1 is provided at a position visible from the outside of the transparent cover 220, and is provided overlapping the display panel 231 (see FIG. 3).

[0092] Therefore, an antenna device 100M1 can be provided that includes a transparent antenna element 110M1 that can be arranged in a position visible from the outside of the transparent cover 220 of the electronic device 200, a transparent portion of the microstrip line 120M1 on the +Z direction side, and a transparent substrate 101.

[0093] Furthermore, the Vivaldi-type antenna element 110M1 and the microstrip line 120M1 can be formed very thin. For example, if the allowable thickness of the antenna device 100M1 is highly restricted, such as 100 μm or less, it is difficult to use an antenna device that requires a certain degree of thickness in the ground layer, such as a patch antenna. In this respect, the antenna device 100M1 including the Vivaldi-type antenna element 110M1 and the microstrip line 120M1, which can be formed very thin, is very advantageous in terms of thinning.

[0094] 16 and 17 are diagrams showing the antenna device 100M2. In FIG. 16 and FIG. 17, the antenna device 100M2 before bending is shown parallel to the YZ plane. The antenna device 100M2 includes portions 100M2A and 100M2B. The portions 100M2A and 100M2B are similar to the portions 100A and 100B shown in FIG. 1, FIG. 2, FIG. 4, and FIG. 5, and the portion 100M2A is a portion that can be seen from the outside of the electronic device 200 or 200A through the transparent cover 220 or 220A of the electronic device 200 or 200A, and the portion 100M2B is a portion that is arranged on the back side of the display operation unit 230 or 230A and cannot be seen from the outside of the electronic device 200 or 200A.

[0095] 16 and 17, as an example, a configuration in which the boundary between the portion 100M2A and the portion 100M2B is 1 / 2 of the way from the end of the microstrip line 120 on the +Z direction side in the Z direction is shown.

[0096] The antenna device 100M2 includes a substrate 101, an antenna element 110, a director 115, and a microstrip line 120. The antenna device 100M2 is a Yagi-Uda antenna in which a director 115 is added to the antenna device 100 shown in FIGS.

[0097] The director 115 is realized by a transparent conductor 300A (see FIG. 6), similarly to the antenna element 110. The length in the Z direction of the microstrip line 120 having the transmission line 121 and the ground layer 122 is shorter than the length in the Z direction of the microstrip line 120 of the antenna device 100 shown in FIGS. 4 and 5, but the configuration is similar.

[0098] Fig. 17(A) shows substrate 101 and components arranged on the surface of substrate 101 in the +X direction, and Fig. 17(B) shows components arranged on the surface of substrate 101 in the +X direction. Note that in Fig. 17(B), the position of substrate 101 is indicated by a dashed line.

[0099] Director 115 has two directors 115A and 115B. In the following, when there is no need to distinguish between the two directors 115A and 115B, they will be simply referred to as director 115. Although Fig. 16 and Fig. 17 show a configuration in which director 115 has two directors 115A and 115B, the number of directors 115 may be one, or three or more.

[0100] The length in the Y direction of directors 115A and 115B is slightly shorter than the length between open ends 111C and 112C of antenna element 110. The distance G in the Z direction between director 115A and director 115B is equal to the distance G in the Z direction between the section between open ends 111C and 112C of antenna element 110 and director 115A.

[0101] In the antenna device 100M2 having such a configuration, the portion where the antenna element 110, the director 115, and a part of the microstrip line 120 on the +Z direction side are provided in the Z direction is the portion 100A shown in Figures 1 and 2. In the antenna device 100M2, the portion where the remaining part of the microstrip line 120 is provided is the portion 100B shown in Figures 1 and 2. Since the portion 100A is located above the display panel 231 shown in Figure 3, it is sufficient that the portion 100A is transparent so as not to interfere with the display.

[0102] FIG. 18 is a diagram showing the relationship between the number of directors 115, the spacing G, and the directivity and gain. FIG. 18(A) shows the directivity characteristics with respect to the spacing G. FIG. 18(B) shows the gain characteristics with respect to the spacing G. The number of directors 115 is 0, 1, 3, and 5. When there is 0 director 115, the antenna element 110 is a dipole antenna, and when there is 1, 3, or 5 directors 115, the antenna element 110 is a Yagi-Uda antenna. Moreover, the directivity represents the angle (deg.) of the main lobe, and the gain represents the gain (dBi) of the main lobe.

[0103] As shown in Fig. 18(A), when the gap G was 1 mm and 2 mm, directivity of about 90 degrees was obtained in all cases where there was one, three, or five directors 115. This means that directivity in the +X direction was obtained in Figs. 16 and 17.

[0104] Furthermore, when there was one director 115, a directivity of about 10 degrees was obtained when the spacing G was 3 mm or more. When there were three directors 115, a directivity of about 10 degrees was obtained when the spacing G was 3 mm and 4 mm, and a directivity of about 90 degrees or more was obtained when it was 5 mm or more. When there were five directors 115, a directivity of about 10 degrees was obtained when the spacing G was 3, and a directivity of about 75 degrees or more was obtained when it was 4 mm or more.

[0105] Since the directivity of a dipole antenna is approximately 35 degrees, it was found that the directivity can be adjusted by selecting the number and quantity of directors 115.

[0106] Furthermore, as shown in FIG. 18(B), when there is one director 115, the gain increases from approximately 2 dBi to approximately 5 dBi when the spacing G is increased from 1 mm to 4 mm, and when the spacing G is 5 mm or more, the gain decreases to approximately 3.5 dBi.

[0107] When there were three and five directors 115, a gain of approximately 4.5 dBi was obtained when the spacing G was 1 mm and 2 mm. When the spacing G was increased from 3 mm or more to 5 mm, the gain gradually decreased to approximately 2 dBi, and when the spacing G became 6 mm, the gain again increased slightly.

[0108] It was confirmed that, regardless of the number of directors 115, by selecting the interval G, a gain equal to or greater than the gain of a dipole antenna (approximately 3.7 dBi) can be obtained.

[0109] 19 is a diagram showing the frequency characteristics of the S11 parameter of antenna device 100M2 having one director 115 and spacing G set to 4 mm. Antenna device 100M2 having one director 115 and spacing G set to 4 mm is a configuration in which the maximum gain is obtained when there is one director 115 (see FIG. 18(B)).

[0110] 19 shows the frequency characteristics of the S11 parameter obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M2 set to 28 GHz. A good band was obtained in which the S11 parameter was −5 dB or less around 28 GHz.

[0111] Fig. 20 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of antenna device 100M2, which has one director 115 and is set to a spacing G of 4 mm, set to 28 GHz. The directivity shown in Fig. 20 is the directivity of the main lobe of antenna device 100M2. The 0 degree direction corresponds to the +Z direction, and the 90 degree direction corresponds to the +X direction. As shown in Fig. 20, it can be seen that directivity in the +Z direction (0 degree direction) has been obtained.

[0112] When an antenna device 100M2 having one director 115 with a spacing G set to 4 mm is attached to an electronic device 200, the directivity is expected to be approximately the same as the directivity when an antenna device 100 is attached to an electronic device 200, as shown in FIG. 10.

[0113] 21 is a diagram showing the frequency characteristics of the S11 parameter of antenna device 100M2 having five directors 115 and a spacing G of 1 mm. Antenna device 100M2 having five directors 115 and a spacing G of 1 mm is a configuration in which the maximum gain is obtained when there are five directors 115 (see FIG. 18(B)).

[0114] 21 shows the frequency characteristics of the S11 parameter obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M2 set to 28 GHz. A good band was obtained in which the S11 parameter was −5 dB or less around 28 GHz.

[0115] Fig. 22 is a diagram showing the directivity obtained by an electromagnetic field simulation performed with the resonant frequency of antenna device 100M2, which has five directors 115 set at a spacing G of 1 mm, set to 28 GHz. The directivity shown in Fig. 22 is the directivity of the main lobe of antenna device 100M2. As shown in Fig. 22, it can be seen that directivity in the +X direction (a direction of 90 degrees) is obtained.

[0116] When antenna device 100M2 having five directors 115 with spacing G set to 1 mm is attached to electronic device 200, the directivity is directed vertically upward from transparent cover 220 of electronic device 200.

[0117] 23 is a diagram illustrating the directivity of the antenna device 100M2 on an exemplary cross section of the electronic device 200A. To make the positions of the portion 100M2A and the portion 100M2B easier to understand, the portion 100M2A is shown in white and the portion 100M2B is shown in gray.

[0118] In Fig. 23, a portion 100M2A of the antenna device 100M2 is provided across the upper surface portion 220A1 of the transparent cover 220A and the curved portion 220A2 on the -Z direction side. The portion 100M2A is a transparent portion in which the antenna element 110, the director 115, and a part of the microstrip line 120 on the +Z direction side shown in Figs. 16 and 17 are provided. The portion 100M2B of the antenna device 100M2 is provided on the back side of the display operation unit 230A. The portion 100M2B is a non-transparent portion in which the remaining part of the microstrip line 120 shown in Figs. 16 and 17 that is not included in the portion 100A is provided.

[0119] In Figure 23, for ease of explanation, part 100M2A of antenna device 100M2 is shown between transparent cover 220A and display operation unit 230A, but part 100M2A of antenna device 100M2 is not limited to being disposed between display operation unit 230A and transparent cover 220A, and may be disposed between layers 232 and 233 shown in Figure 3, between layer 233 and adhesive layer 234, or between layer 232 and display panel 231.

[0120] In this way, in the electronic device 200A including the antenna device 100M2, the directivity shown in FIG. 22 is in the direction indicated by (2) in FIG. 23. That is, the antenna device 100M2 can radiate radio waves in the direction indicated by (2) and can receive radio waves in the direction indicated by (2). The direction indicated by (2) is the direction of radiation along the normal direction of the upper surface portion 220A1 of the transparent cover 220A of the electronic device 200A. The upper surface portion 220A1 of the transparent cover 220A is a part of the surface of the transparent cover 220A and is also a part of the surface of the electronic device 200A. Since the antenna device 100 has directivity in such a direction (2), it is easy for the antenna device 100 to communicate with a communication device outside the electronic device 200.

[0121] Antenna device 100M2 has a configuration in which director 115 is added to antenna device 100. Transparent antenna element 110, director 115, and a portion of microstrip line 120 included in portion 100M2A are provided in positions visible from the outside of transparent cover 220, and are provided overlapping display panel 231 (see FIG. 3).

[0122] Therefore, an antenna device 100M2 can be provided, which includes a transparent antenna element 110 that can be positioned in a position visible from the outside of the transparent cover 220 of the electronic device 200, a transparent director 115, a transparent portion included in portion 100M2A of the microstrip line 120, and a transparent substrate 101.

[0123] Moreover, the antenna element 110, the director 115, and the microstrip line 120 can be formed very thin. For example, if there are significant restrictions on the allowable thickness of the antenna device 100M2, such as 100 μm or less, it is difficult to use an antenna device that requires a certain degree of thickness in the ground layer, such as a patch antenna. In this respect, the antenna device 100M2 including the antenna element 110, the director 115, and the microstrip line 120, which can be formed very thin, is very advantageous in terms of thinning.

[0124] Fig. 24 is a cross-sectional view showing an electronic device 200B according to a modified example of the embodiment. Fig. 24 shows a cross-section corresponding to Fig. 11. The electronic device 200B includes an antenna device 100 and an antenna device 100M2. The antenna device 100 and the antenna device 100M2 include a common substrate 101B instead of the substrate 101 shown in Figs. 4, 5, 16, and 17. The antenna device 100 and the antenna device 100M2 may have configurations with different resonant frequencies.

[0125] The substrate 101B is larger than the display operation unit 230A in a plan view, and is provided over the entire area between the transparent cover 220A and the display operation unit 230A. Ends 101B1 and 101B2 of the substrate 101B are bent and positioned on the back side of the display operation unit 230A, and are connected to the wiring substrate 240. The antenna device 100 is provided on the upper surface 220A1 and the curved portion 220A2 on the -Z direction side. The antenna device 100M2 is provided on the upper surface 220A1 and the curved portion 220A3 on the +Z direction side. Therefore, in the portion in the Z direction where the antenna device 100 and the antenna device 100M2 are not provided, only the substrate 101B is provided between the transparent cover 220A and the display operation unit 230A.

[0126] The reason why substrate 101B is made larger than display operation unit 230A in a planar view and ends 101B1, 101B2 of substrate 101B are positioned on the back side of display operation unit 230A is to prevent ends 101B1, 101B2 from being seen from outside transparent cover 220A, in consideration of cases where ends 101B1, 101B2 of substrate 101B are noticeable.

[0127] Therefore, the ends 101B1 and 101B2 only need to be located on the rear side of the display operation unit 230A including the display panel 231 (see FIG. 3), and do not need to be connected to the wiring board 240 as shown in FIG.

[0128] Further, the end of substrate 101B is also bent in the XY cross section and positioned behind display operation unit 230A so that the end of substrate 101B is not visible from the outside of transparent cover 220A.

[0129] In Fig. 24, the portion 100A of the antenna device 100 is provided across the flat upper surface portion 220A1 and the curved portion 220A2 of the transparent cover 220A. The range of the portion 100A is the same as that in Fig. 11. The range of the portion 100B is also the same as that in Fig. 11. In Fig. 24, for convenience of explanation, the portion 100A of the antenna device 100 is shown between the transparent cover 220A and the display operation unit 230A, but the portion 100A of the antenna device 100 is not limited to being disposed between the display operation unit 230A and the transparent cover 220A, and may be disposed between the layers 232 and 233 shown in Fig. 3, between the layer 233 and the adhesive layer 234, or between the layer 232 and the display panel 231.

[0130] 24, a portion 100M2A of the antenna device 100M2 is provided across the curved portion 220A3 on the +Z direction side of the transparent cover 220A and the upper surface portion 220A1. For convenience of explanation, in FIG. 24, the portion 100M2A of the antenna device 100M2 is shown between the transparent cover 220A and the display operation unit 230A, but the portion 100M2A of the antenna device 100M2 is not limited to being disposed between the display operation unit 230A and the transparent cover 220A, and may be disposed between the layers 232 and 233 shown in FIG. 3, between the layer 233 and the adhesive layer 234, or between the layer 232 and the display panel 231.

[0131] The antenna device 100 and the antenna device 100M2 have a substrate 101B that is larger than the display operation unit 230A, and ends 101B1 and 101B2 of the substrate 101B are positioned on the rear side of the display operation unit 230A.

[0132] This makes it possible to provide the antenna device 100 and the antenna device 100M2 with a high design quality in which the ends 101B1 and 101B2 of the substrate 101B are not visible from the outside of the transparent cover 220A.

[0133] Further, although the embodiment in which the electronic device 200B includes the antenna device 100 and the antenna device 100M2 has been described here, the electronic device 200B may include either the antenna device 100 or the antenna device 100M2. Further, the electronic device 200B may include an antenna device other than the antenna device 100 and the antenna device 100M2, or may include three or more antenna devices.

[0134] When the electronic device 200B includes a plurality of antenna devices with different resonant frequencies, it is possible to provide the electronic device 200B capable of communicating in a plurality of communication bands.

[0135] 25 is a diagram showing an antenna device 100M2. The antenna device 100M2 includes a substrate 101, an antenna element 110, a director 115, and a microstrip line 120. The antenna element 110 includes elements 111 and 112, and the microstrip line 120 includes a transmission line 121 and a ground layer 122.

[0136] Here, a model in which the antenna device 100M2 is bent at the feed point 111A in the Z direction is considered. Figure 26 is a diagram for explaining a method for bending the antenna device 100M2. Figures 26(A) and (B) show exemplary portions 100M2A and 100M2B.

[0137] Fig. 26(A) shows the antenna device 100M2 in an unbent state, and Fig. 26(B) shows the antenna device 100M2 in a bent state. Such bending of the antenna device 100M2 is performed using a simulation model, but for ease of understanding, the bending of the antenna device 100M2 will be described here using a virtual jig 105.

[0138] 26(A) and (B), the model of the antenna device 100M2 includes covers 102 and 103. The covers 102 and 103 are attached to the surfaces of the antenna device 100M2 on the +X direction side and the -X direction side, respectively, with adhesive layers 102A and 103A. The size of the covers 102 and 103 is equal to the size of the substrate 101.

[0139] The jig 105 has an end 105A that is curved with a radius of 1 mm in the XZ cross section and is long in the Y direction. As shown in Fig. 26(A), the end 105A is pressed against the surface on the -X direction side of the antenna device 100M2. When the position of the end 105A in the Z direction is Z = 0 mm, the end 105A is at the position of the feed point 111A. In other words, when the position of the end 105A in the Z direction is Z = 0 mm, the position of the end 105A in the Z direction is equal to the position of the boundary between the antenna element 110 and the microstrip line 120.

[0140] As shown in Fig. 26(B), the antenna element 110 side of the antenna device 100M2 is bent 90 degrees in the clockwise direction in Fig. 26(B) relative to the microstrip line 120 side. At this time, the XYZ coordinates are also rotated 90 degrees. That is, even after bending, the +Z direction remains the endfire direction of the antenna element 110.

[0141] When such bending of antenna device 100M2 was performed by setting jig 105 to three different positions, Z=0 mm, Z=2 mm, and Z=4 mm, the models shown in Figures 27(A) to (C) were obtained. Figure 27 is a diagram showing a bending model of antenna device 100M2.

[0142] The model shown in Fig. 27(A) is a model of the antenna device 100M2 bent at the position Z = 0 mm. The model shown in Fig. 27(B) is a model of the antenna device 100M2 bent at the position Z = 2 mm. The model shown in Fig. 27(C) is a model of the antenna device 100M2 bent at the position Z = 4 mm.

[0143] When the position of jig 105 changes from Z=0 mm to Z=2 mm or Z=4 mm, the position of jig 105 shifts toward the +Z direction side of the boundary between antenna element 110 and microstrip line 120. For this reason, when Z=2 mm and Z=4 mm, antenna element 110 is bent midway.

[0144] Fig. 28 is a diagram showing the directivities of antenna devices 100M2 with different bending positions. Fig. 28 shows the directivities obtained from four models of antenna devices 100M2 with bending positions of Z=0 mm, Z=2 mm, Z=4 mm, and Z=6 mm.

[0145] At Z=0 mm, the directivity is in the backfire direction of 180 degrees (-Z direction), whereas at Z=2 mm, 4 mm, and 6 mm, the directivity is in the vertical upward direction of 90 degrees (+X direction).

[0146] In this way, it was found that the directivity of the antenna device 100M2 can be adjusted by changing the bending position.

[0147] Fig. 29 is a diagram showing an antenna device 100M3 according to a modified example of the embodiment. The antenna device 100M3 includes a substrate 101, an antenna element 110, a reflector 116, and a microstrip line 120. The antenna device 100M3 has a configuration including a reflector 116 instead of the director 115 of the antenna device 100M2 shown in Figs. 16 and 17. The reflector 116 is realized by a transparent conductor 300A (see Fig. 6), similar to the antenna element 110.

[0148] The antenna device 100M3 includes portions 100M3A and 100M3B. The portions 100M3A and 100M3B are similar to the portions 100A and 100B shown in Fig. 1, Fig. 2, Fig. 4, and Fig. 5. The portion 100M3A is a portion that is visible from the outside of the electronic device 200 or 200A through the transparent cover 220 or 220A of the electronic device 200 or 200A when attached to the electronic device 200 or 200A, and the portion 100M3B is a portion that is disposed on the back side of the display operation unit 230 or 230A and is not visible from the outside of the electronic device 200 or 200A.

[0149] FIG. 29 shows, as an example, a configuration in which the boundary between the portion 100M3A and the portion 100M3B is half the length from the end of the microstrip line 120 on the +Z direction side in the Z direction.

[0150] The length of reflector 116 in the Y direction is slightly longer than the length of antenna element 110 between open ends 111C and 112C in the Y direction.

[0151] Fig. 30 is a diagram showing a model of an antenna device 100M3. The antenna device 100M3 shown in Fig. 30 is bent at a position of Z=1 mm. The position of Z=1 mm is 1 mm away from the power feed point 111A in the +Z direction.

[0152] Fig. 31 is a diagram showing the frequency characteristics of the S11 parameter of the antenna device 100M3 bent at the position Z=1 mm. Fig. 31 shows the frequency characteristics of the S11 parameter obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M3 set to 28 GHz. A good band was obtained in which the S11 parameter was -5 dB or less around 28 GHz. Note that the band of -5 dB or less around 41 GHz was generated unintentionally.

[0153] Fig. 32 is a diagram showing the directivity obtained by an electromagnetic field simulation performed by setting the resonant frequency of the antenna device 100M3 bent at the position Z = 1 mm to 28 GHz. The directivity shown in Fig. 32 is the directivity of the main lobe of the antenna device 100M3. The 0 degree direction corresponds to the +Z direction (endfire direction), the 90 degree direction corresponds to the +X direction, and 180 degrees corresponds to the -Z direction (backfire direction). As shown in Fig. 32, it can be seen that directivity in the -Z direction (backfire direction) has been obtained.

[0154] It is believed that the directivity in the backfire direction is achieved due to the synergistic effect of the antenna device 100M3 including the reflector 116 and the ground layer 122 being bent 90 degrees relative to the antenna element 110, thereby shifting the direction from the backfire direction of the antenna element 110.

[0155] The antenna device 100M3 has a configuration in which a reflector 116 is added to and folded over the antenna device 100. The transparent antenna element 110 and the reflector 116 can be provided in a position visible from the outside of the transparent cover 220.

[0156] Therefore, an antenna device 100M3 can be provided, which includes a transparent antenna element 110 that can be positioned in a position visible from the outside of the transparent cover 220 of the electronic device 200, a transparent reflector 116, a transparent portion of the microstrip line 120 on the +Z direction side, and a transparent substrate 101.

[0157] Moreover, the antenna element 110, the reflector 116, and the microstrip line 120 can be formed very thin. For example, if there are significant restrictions on the allowable thickness of the antenna device 100M3, such as 100 μm or less, it is difficult to use an antenna device that requires a certain degree of thickness in the ground layer, such as a patch antenna. In this respect, the antenna device 100M3 including the antenna element 110, the reflector 116, and the microstrip line 120, which can be formed very thin, is very advantageous in terms of thinning.

[0158] 33 and 34 are diagrams showing an antenna device 100M4. The antenna device 100M4 includes a substrate 101, an antenna element 110, a director 115, and a microstrip line 120. The antenna device 100M4 is a Yagi-Uda antenna, and has a configuration for use in the sub-6 GHz band (Sub6) of the fifth generation mobile communication system (5G).

[0159] The antenna device 100M4 includes portions 100M4A and 100M4B. The portions 100M4A and 100M4B are similar to the portions 100A and 100B shown in Fig. 1, Fig. 2, Fig. 4, and Fig. 5. The portion 100M4A is a portion that is visible from the outside of the electronic device 200 or 200A through the transparent cover 220 or 220A of the electronic device 200 or 200A when attached to the electronic device 200 or 200A, and the portion 100M4B is a portion that is disposed on the back side of the display operation unit 230 or 230A and is not visible from the outside of the electronic device 200 or 200A.

[0160] 33 and 34, as an example, a configuration in which the boundary between the portion 100M4A and the portion 100M4B is 1 / 2 of the way from the end of the microstrip line 120 on the +Z direction side in the Z direction is shown.

[0161] Fig. 34(A) shows substrate 101 and components arranged on the surface of substrate 101 in the +X direction, and Fig. 34(B) shows components arranged on the surface of substrate 101 in the +X direction. Note that in Fig. 34(B), the position of substrate 101 is indicated by a dashed line.

[0162] The antenna device 100M4 includes one director 115, for example.

[0163] Fig. 35 is a diagram showing the frequency characteristics of the S11 parameter of an antenna device 100M4 for Sub6 having one director 115. Fig. 35 shows the frequency characteristics of the S11 parameter obtained by an electromagnetic field simulation performed with the resonant frequency of the antenna device 100M4 set to 3.5 GHz. A good band was obtained in which the S11 parameter was -5 dB or less around 3.5 GHz.

[0164] Fig. 36 is a diagram showing the directivity obtained by an electromagnetic field simulation performed by setting the resonant frequency of Sub6 antenna device 100M4, which has one director 115, to 3.5 GHz. The directivity shown in Fig. 36 is the directivity of the main lobe of antenna device 100M4. The 0 degree direction corresponds to the +Z direction, and the 90 degree direction corresponds to the +X direction. As shown in Fig. 36, it can be seen that directivity in the +Z direction (0 degree direction) has been obtained.

[0165] The directivity when an antenna device 100M4 for Sub6 having one director 115 is attached to electronic device 200 is considered to be approximately the same as the directivity when antenna device 100 is attached to electronic device 200 as shown in FIG.

[0166] Antenna device 100M4 has a configuration in which director 115 is added to antenna device 100 to make it sized for Sub6. Transparent antenna element 110 and director 115 are provided in a position visible from the outside of transparent cover 220, and are provided overlapping display panel 231 (see FIG. 3).

[0167] Therefore, an antenna device 100M4 can be provided, which includes a transparent antenna element 110 that can be arranged in a position visible from the outside of the transparent cover 220 of the electronic device 200, a transparent director 115, a transparent portion of the microstrip line 120 on the +Z direction side, and a transparent substrate 101.

[0168] Moreover, the antenna element 110, the director 115, and the microstrip line 120 can be formed very thin. For example, if there are significant restrictions on the allowable thickness of the antenna device 100M4, such as 100 μm or less, it is difficult to use an antenna device that requires a certain degree of thickness in the ground layer, such as a patch antenna. In this respect, the antenna device 100M4 including the antenna element 110, the director 115, and the microstrip line 120, which can be formed very thin, is very advantageous in terms of thinning.

[0169] 37 is a diagram showing an electronic device 200C according to a modified example of the embodiment. The electronic device 200C includes an antenna device 100M3 (see FIG. 29) having directivity in the backfire direction, instead of the antenna device 100 of the electronic device 200A shown in FIG.

[0170] Antenna device 100M3 is disposed such that the folded portion of antenna device 100M3 is located behind curved portion 220A2 on the -Z direction side of transparent cover 220A, and is capable of emitting radio waves in the direction indicated by (3) and receiving radio waves in the direction indicated by (3). The direction indicated by (3) is the direction of radiation from curved portion 220A2 of transparent cover 220 of electronic device 200A toward the outside of electronic device 200A. Since antenna device 100M3 has directivity toward such direction (3), it is easy for antenna device 100M3 to communicate with a communication device outside electronic device 200A.

[0171] In this way, by disposing antenna device 100M3 having directivity in the backfire direction on the back side of curved portion 220A2 of transparent cover 220A, directivity facing outward, farther away from transparent cover 220 and housing 210, can be obtained.

[0172] Fig. 38 is a diagram showing an electronic device 200D according to a modified example of the embodiment. In electronic device 200D, antenna device 100M3 of electronic device 200C shown in Fig. 37 is changed to antenna device 100 shown in Fig. 4 and Fig. 5. Antenna device 100 has directivity in the endfire direction.

[0173] The antenna device 100 is disposed on the back side of the curved portion 220A2 on the -Z direction side of the transparent cover 220A, gently bent between the portion 100A and the portion 100B, and can radiate radio waves in the direction indicated by (4) and can receive radio waves in the direction indicated by (4). The direction indicated by (4) is the direction in which radio waves are radiated from the upper surface portion 220A1 and the curved portion 220A2 of the transparent cover 220 of the electronic device 200A toward the outside of the electronic device 200A. Since the antenna device 100M3 has directivity toward such direction (4), it is easy for the antenna device 100M3 to communicate with a communication device outside the electronic device 200A.

[0174] In this way, by disposing antenna device 100 having directivity in the endfire direction on the back side of curved portion 220A2 of transparent cover 220A, directivity facing outward, away from transparent cover 220 and housing 210, can be obtained.

[0175] The above describes an antenna device according to an exemplary embodiment of the present invention. However, the present invention is not limited to the specifically disclosed embodiment, and various modifications and variations are possible without departing from the scope of the claims.

[0176] This international application claims priority to Japanese Patent Application No. 2020-016621, filed on February 3, 2020, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0177] 100, 100M1, 100M2, 100M3, 100M4 Antenna Equipment 101, 101B board 110, 110M1 Antenna Elements 111, 111M1, 112, 112M1 elements 120, 120M1 Microstrip Line 121 Transmission Line 122 Ground Layer 200, 200A, 200B, 200C, 200D Electronic equipment 210 Cabinet 220 Transparent Cover 230 Display operation section

Claims

1. A transparent flexible substrate provided on an inner surface side opposite to an outer surface of a glass or resin transparent cover of an electronic device; a transparent antenna element provided at a position on the flexible substrate that can be seen from the outside of the transparent cover and has directivity facing the outside of the electronic device; Including, An antenna device, wherein the directivity of the antenna element is an endfire direction, and the endfire direction faces outside the electronic device.

2. a power supply line having a ground layer and a transmission line provided on the flexible substrate and having a predetermined characteristic impedance, the power supply line supplying power to the antenna element; the flexible substrate is bent between a tip side of the antenna element and an end of the ground layer farther from the antenna element, The antenna device according to claim 1 , wherein the endfire direction is a direction radiated from an outer surface of the transparent cover.

3. A transparent flexible substrate provided on an inner surface side opposite to an outer surface of a glass or resin transparent cover of an electronic device; a transparent antenna element provided at a position on the flexible substrate that can be seen from the outside of the transparent cover and has directivity facing the outside of the electronic device; Including, An antenna device, wherein the directivity of the antenna element is a backfire direction, and the backfire direction faces an outside of the electronic device.

4. a power supply line having a ground layer and a transmission line provided on the flexible substrate and having a predetermined characteristic impedance, the power supply line supplying power to the antenna element; the flexible substrate is bent between a tip side of the antenna element and an end of the ground layer farther from the antenna element, The antenna device according to claim 3 , wherein the backfire direction is a direction radiated from an outer surface of the transparent cover.

5. The transparent cover has a curved portion that is three-dimensionally curved, the electronic device includes a display panel curved along an inner surface of the curved transparent cover; 5. The antenna device according to claim 2, wherein the bent portion of the flexible substrate is provided on a rear side of the curved portion of the display panel.

6. A transparent flexible substrate provided on an inner surface side opposite to an outer surface of a glass or resin transparent cover of an electronic device; a transparent antenna element provided at a position on the flexible substrate that can be seen from the outside of the transparent cover and has directivity facing the outside of the electronic device; Including, The directivity of the antenna element is a direction radiated from a surface of the flexible substrate, A section of the flexible substrate on which the antenna element is provided is aligned along an inner surface of the transparent cover, An antenna device, wherein the directivity of the antenna element is a direction radiated from the outer surface of the transparent cover.

7. 7. The antenna device according to claim 1, wherein said antenna element is realized by a mesh-shaped conductive line having a transmittance equal to or greater than a predetermined value.

8. 5. The antenna device according to claim 2, wherein a section of said feed line that is provided in a position visible from outside said transparent cover is transparent.

9. 9. The antenna device according to claim 8, wherein a section of said feed line that is provided at a position visible from outside said transparent cover is realized by a mesh-shaped conductive line having a transmittance equal to or greater than a predetermined value.

10. 10. The antenna device according to claim 2, wherein a section of the power supply line that is located in a position that cannot be seen from outside the transparent cover has a pair of conductive layers provided on both sides of the flexible substrate and a plurality of cylindrical or cylindrical conductors that penetrate the flexible substrate and connect the pair of conductive layers, and is composed of a transmission line shielded by the pair of conductive layers and the plurality of cylindrical or cylindrical conductors.

11. The transparent cover has a curved portion that is three-dimensionally curved, the electronic device includes a display panel curved along an inner surface of the curved transparent cover; the flexible substrate is provided between the transparent cover and the display panel and covers the entire display surface of the display panel; 11. The antenna device according to claim 1, wherein an end edge of the flexible substrate is provided on a rear side of the display panel when viewed from the outer surface of the transparent cover.

12. 12. The antenna device according to claim 1, wherein the antenna element is a dipole antenna, a Vivaldi antenna, a Yagi-Uda antenna, a monopole antenna, a tapered slot antenna, a slot antenna, or a log-periodic antenna.

13. The antenna further includes one or more parasitic elements fed by the antenna element, 12. The antenna device according to claim 1, wherein the antenna element and the one or more parasitic elements provide a directivity toward an outside of the electronic device.

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