Radio wave reflecting device

Abstract

The radio wave reflecting device includes: a plurality of first patch electrodes; a plurality of second patch electrodes having a different size from the plurality of first patch electrodes; a ground electrode facing the plurality of first patch electrodes and the plurality of second patch electrodes and provided separately from the plurality of first patch electrodes and the plurality of second patch electrodes; and a liquid crystal layer provided between the plurality of first patch electrodes and the plurality of second patch electrodes and the ground electrode, the plurality of first patch electrodes and the plurality of second patch electrodes being arranged in a first direction and a second direction in a plan view, and the liquid crystal layer being arranged in the first direction and the second direction when the distance between the centers of two adjacent first patch electrodes is set as a distance W1. The second patch electrode is disposed at a position separated from the first patch electrode by a distance (W1 / 2) parallel to the first direction and by a distance (W1 / 2) parallel to the second direction.

Description

Technical Field

[0001] One embodiment of the present invention relates to a radio wave reflecting device capable of controlling the traveling direction of reflected radio waves. Background Art

[0002] A phased array antenna device includes a plurality of antenna elements arranged in a planar shape. In a phased array antenna device, the amplitude and phase of a high-frequency signal applied to each of the plurality of antenna elements are adjusted. As a result, the phased array antenna device can control the directivity of the antenna while the plurality of antenna elements are each fixed.

[0003] Phased array antenna devices require phase shifters to adjust the amplitude and phase of high frequency signals applied to each of the plurality of antenna elements. For example, Patent Document 1 discloses a phased array antenna device using a phase shifter that utilizes a change in dielectric constant caused by the orientation state of liquid crystal.

[0004] The antenna element of the phased array antenna device disclosed in Patent Document 1 includes a plurality of strip-shaped wirings, a planar electrode facing the plurality of strip-shaped wirings, and a liquid crystal layer provided between the plurality of strip-shaped wirings and the planar electrode. Different voltages are applied to the plurality of strip-shaped wirings, for example. As a result, the reflected waves generated by adjusting the liquid crystal orientation of the liquid crystal layer according to the antenna element can be overlapped, thereby changing the phase of the radio wave. As a result, the reflection direction of the radio wave can be set to an arbitrary direction.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Laid-Open No. 11-103201 Summary of the invention

[0008] In the field of communications, the introduction of the fifth generation communication standard known as 5G is being promoted. In this communication standard, for example, the frequency of the millimeter wave band of 26GHz to 28GHz is adopted. Communications based on the 5G standard can achieve very high throughput by adopting the frequency of the millimeter wave band, and can be transmitted with a large bandwidth. However, the radio waves obtained based on the frequency of the millimeter wave band have the characteristics of high straightness and difficulty in propagating around obstacles. Therefore, in urban areas, etc., the small communication area that can be covered by the 5G standard has become a problem.

[0009] In order to avoid obstacles and expand the communication area, a reflector is used to change the propagation direction of radio waves. However, in the phased array antenna device described in Patent Document 1, the phase change of radio waves is not sufficient and the radio waves cannot be reflected in the target direction.

[0010] In view of this problem, one of the objects of one embodiment of the present invention is to improve the reflection gain of a radio wave reflection device.

[0011] An electric wave reflecting device according to one embodiment of the present invention includes: a plurality of first patch electrodes; a plurality of second patch electrodes having a size different from that of the plurality of first patch electrodes; a ground electrode, which is opposite to the plurality of first patch electrodes and the plurality of second patch electrodes and is separated from the plurality of first patch electrodes and the plurality of second patch electrodes; and a liquid crystal layer, which is arranged between the plurality of first patch electrodes and the plurality of second patch electrodes and the ground electrode, wherein the plurality of first patch electrodes and the plurality of second patch electrodes are arranged in a matrix in a first direction and in a second direction intersecting the first direction when viewed from above, and when the distance between the centers of two adjacent first patch electrodes is set to a distance W1, the second patch electrode is arranged at a position which is a distance W1 / 2 away from the first patch electrode parallel to the first direction and a distance W1 / 2 away from the second direction with respect to the position of the first patch electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a plan view showing a reflector unit cell used in the radio wave reflecting device according to the first embodiment of the present invention.

[0013] Figure 2 Yes means Figure 1 A cross-sectional view taken along line A1-A2 is shown.

[0014] Figure 3 Yes means Figure 1 A cross-sectional view taken along the B1-B2 line shown.

[0015] Figure 4 Yes means Figure 1 A cross-sectional view of the cross-sectional plane along the C1-C2 line or the cross-sectional view of the cross-sectional plane along the C3-C4 line shown.

[0016] Figure 5 It is a diagram for explaining the first sub-cell included in the reflector unit cell according to the first embodiment of the present invention.

[0017] Figure 6 It is a diagram for explaining the second sub-cell included in the reflector unit cell according to the first embodiment of the present invention.

[0018] Figure 7 This is a diagram showing a state in which no voltage is applied between the patch electrode and the ground electrode in the reflector unit cell used in the radio wave reflection device according to the first embodiment of the present invention.

[0019] Figure 8This is a diagram showing a state where a voltage is applied between a patch electrode and a ground electrode in a reflector unit cell used in the radio wave reflecting device according to the first embodiment of the present invention.

[0020] Fig. 9 This is a diagram schematically showing how the traveling direction of the reflected wave changes by the radio wave reflecting device according to the first embodiment of the present invention.

[0021] Fig.10 It is a plan view showing the structure of the radio wave reflection device according to the first embodiment of the present invention.

[0022] Fig.11 Yes means Fig.10 A top view of the structure of the reflector unit cell is shown.

[0023] Fig.12 It is a cross-sectional view showing a cut surface of a reflector unit cell in the radio wave reflecting device according to the first embodiment of the present invention.

[0024] Fig.13 The structure of a radio wave reflection device according to a second embodiment of the present invention is shown.

[0025] Fig.14 It is a plan view showing a reflector unit cell used in the radio wave reflecting device according to the second embodiment of the present invention.

[0026] Fig.15 Yes means Fig.14 A cross-sectional view of a section taken along line D1 - D2 is shown.

[0027] Fig.16 Yes means Fig.14 A cross-sectional view of the section plane along the E1-E2 line shown. DETAILED DESCRIPTION

[0028] Hereinafter, the embodiments of the present invention will be described with reference to the accompanying drawings, etc. Among them, the present invention can be implemented in a plurality of different forms, and is not limited to the contents of the following embodiments and is explained. In order to make the description clearer, there is a case where the width, thickness, shape, etc. of each part are schematically shown in the accompanying drawings compared with the actual form, but it is only an example and does not limit the interpretation of the present invention. In addition, in this specification and each figure, sometimes the same figure mark (or a, b, etc. are marked after the number) is used to mark the same elements as the elements described in the figures that have appeared, and the detailed description is appropriately omitted. And the text marked as "the first" and "the second" for each element is a convenient mark for distinguishing each element, and does not have any meaning other than this unless otherwise specified.

[0029] In this specification, when a certain component or region is located "on (or below)" other components or regions, unless otherwise specified, it includes not only the case where it is located directly above (or directly below) other components or regions, but also the case where it is located above (or below) other components or regions, that is, it also includes the case where it is above (or below) other components or regions and includes other structural elements in between.

[0030] In the specification of the present application, the X direction intersects with the Y direction. The X direction is referred to as a first direction, and the Y direction is referred to as a second direction.

[0031] In the specification of the present application, when the expressions “same” and “identical” are used, “same” and “identical” may include errors within a designed range.

[0032] <First Embodiment>

[0033] In the first embodiment, referring to Figures 1 to 12 A radio wave reflection device 100a capable of dual-axis reflection control (see Fig.10 ).

[0034] <1. Reflector unit>

[0035] First, the reflection plate unit cell 102 used in the radio wave reflection device 100a according to the first embodiment of the present invention will be described. The radio wave reflection device 100a includes a plurality of reflection plate unit cells 102.

[0036] Figure 1 This is a plan view of the reflector unit cell 102 as viewed from above (the side where radio waves are incident). Figure 2 Yes means Figure 1 The cross-sectional view of the section plane along the A1-A2 line shown, Figure 3 Yes means Figure 1 The cross-sectional view of the section plane along the B1-B2 line shown, Figure 4 Yes means Figure 1 A cross-sectional view of the cross-sectional plane along the C1-C2 line or the cross-sectional view of the cross-sectional plane along the C3-C4 line shown. Figure 5 1 is a diagram for explaining the first sub-cell 103a included in the reflector cell 102. Figure 6 This is a diagram for explaining the second sub-cell 103 b included in the reflector cell 102 .

[0037] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 or Figure 6As shown, the reflector unit cell 102 includes a first sub-cell 103a and a second sub-cell 103b. A portion of the first sub-cell 103a overlaps with the second sub-cell 103b, and a portion of the second sub-cell 103b overlaps with the first sub-cell 103a. The first sub-cell 103a includes an opposing substrate 106, a ground electrode 110, a second orientation film 112b, a liquid crystal layer 114, a first orientation film 112a, a patch electrode 108a, an array layer 180, and a dielectric substrate 104. In addition, the second sub-cell 103b includes a dielectric substrate 104, an opposing substrate 106, a ground electrode 110, a second orientation film 112b, a liquid crystal layer 114, a first orientation film 112a, a patch electrode 108b, an array layer 180, and a dielectric substrate 104. In the first sub-cell 103a and the second sub-cell 103b, the dielectric substrate 104 can also be constituted as a single layer and regarded as a dielectric layer. Therefore, the dielectric substrate 104 may be referred to as a dielectric layer. Although the details will be described later, the array layer 180 includes a switch element 134 (see FIG. 1 ) electrically connected to the patch electrodes 108a and 108b, respectively. Fig.11 ). In some cases, the patch electrode 108a is referred to as a first patch electrode, and the patch electrode 108b is referred to as a second patch electrode.

[0038] like Figure 2 to Figure 4 As shown, the array layer 180 is provided on the dielectric substrate 104. The patch electrodes 108a and 108b are provided on the array layer 180. The first orientation film 112a is provided to cover the patch electrodes 108a and 108b. The ground electrode 110 is provided on the counter substrate 106. The second orientation film 112b is provided to cover the ground electrode 110. The patch electrodes 108a and 108b are arranged to face the ground electrode 110. A liquid crystal layer 114 is provided between the patch electrodes 108a and 108b and the ground electrode 110. The first orientation film 112a is sandwiched between the patch electrodes 108a and 108b and the liquid crystal layer 114. The second orientation film 112b is sandwiched between the ground electrode 110 and the liquid crystal layer 114. The thickness T of the dielectric substrate 104 is set to be, for example, the length from the surface of the patch electrode 108 on the liquid crystal layer 114 side to the surface of the dielectric substrate 104 opposite to the surface where the patch electrode 108 is provided.

[0039] In the radio wave reflection device 100a, the difference between the first sub-cell 103a and the second sub-cell 103b is, for example, the size of the patch electrode 108a and the patch electrode 108b. Figure 1In the example shown, the size of the patch electrode 108a is larger than the size of the patch electrode 108b. In addition, the size of the patch electrode 108a may be smaller than the size of the patch electrode 108b. In the specification of the present application, when the first sub-cell 103a and the second sub-cell 103b are not particularly distinguished, they are simply described as the reflector cell 102. In addition, when there is no need to particularly distinguish between the patch electrode 108a and the patch electrode 108b, they are simply described as the patch electrode 108.

[0040] like Figure 5 As shown in FIG. 1 , when the plurality of first sub-unit cells 103a are viewed from above, the plurality of patch electrodes 108a are arranged in a matrix in the X direction (first direction) and the Y direction (second direction) intersecting the X direction. The distance between the center O1 of the patch electrode 108a parallel to the X direction and the center O1 of the adjacent patch electrode 108a is the distance W1. In addition, similarly to the X direction, the distance between the center O1 of the patch electrode 108a parallel to the Y direction and the center O1 of the adjacent patch electrode 108a is the distance W1. That is, the plurality of patch electrodes 108a are arranged at the same pitch (distance W1) in the X direction and the Y direction. In other words, the plurality of first sub-unit cells 103a are arranged at the same pitch (distance W1) in the X direction and the Y direction.

[0041] The shape of the patch electrode 108a is, for example, a cross shape. The length of the cross-shaped pattern parallel to the X direction is the same as the length of the cross-shaped pattern parallel to the Y direction, and the length is length W3. The width of the cross-shaped pattern parallel to the X direction is the same as the width of the cross-shaped pattern parallel to the Y direction, and the width is width W4. In addition, the distance between the patch electrode 108a and the adjacent patch electrode 108a is distance W2.

[0042] like Figure 6 As shown in FIG. 1 , when the plurality of second sub-cells 103b are viewed from above, the plurality of patch electrodes 108b are arranged in a matrix in the X direction and the Y direction in the same manner as the plurality of patch electrodes 108a. The distance between the center O2 of the patch electrode 108b parallel to the X direction and the center O2 of the adjacent patch electrode 108b, and the distance between the center O2 of the patch electrode 108b parallel to the Y direction and the center O2 of the adjacent patch electrode 108a are distance W5. That is, the plurality of patch electrodes 108b are arranged at the same pitch (distance W5) in the X direction and the Y direction. In other words, the plurality of second sub-cells 103b are arranged at the same pitch (distance W5) in the X direction and the Y direction. In this specification, the distance W5 is the same as the distance W1. That is, the second sub-cells 103b are arranged at the same pitch as the first sub-cells 103a.

[0043] The shape of the patch electrode 108b is similar to the shape of the patch electrode 108a, for example, a cross shape. In the patch electrode 108b, the length of the cross-shaped pattern parallel to the X direction is the same as the length of the cross-shaped pattern parallel to the Y direction, and the length is length W7. The width of the cross-shaped pattern parallel to the X direction is the same as the width of the cross-shaped pattern parallel to the Y direction, and the width is width W8. In addition, the distance between the patch electrode 108b and the adjacent patch electrode 108b is distance W6.

[0044] For example, the distance W1 is the same as the distance W5 , the distance W2 is shorter than the distance W6 , the width W3 is longer than the length W7 , and the width W4 is longer than the width W8 .

[0045] The cross shape is a shape having four-fold rotational symmetry with respect to the center O1 of the patch electrode 108a and the center O2 of the patch electrode 108b. Since the patch electrode 108a has rotational symmetry with respect to the center O1 of the patch electrode 108a, the anisotropy related to the reflection of the radio wave can be reduced with respect to the vertical polarization wave and the horizontal polarization wave of the incident radio wave. Similarly to the patch electrode 108a, since the patch electrode 108b has rotational symmetry with respect to the center O2 of the patch electrode 108b, the anisotropy related to the reflection of the radio wave can be reduced with respect to the vertical polarization wave and the horizontal polarization wave of the incident radio wave. That is, it is possible to suppress the anisotropy related to the reflection of the radio wave. Figure 1 , Figure 5 and Figure 6 The bias of the vertically polarized waves and the horizontally polarized waves in the XY plane makes the vertically polarized waves and the horizontally polarized waves reflected evenly.

[0046] like Figure 1 , Figure 5 and Figure 6 As shown, when the radio wave reflection device 100a is viewed from above, the plurality of patch electrodes 108a and the plurality of patch electrodes 108b are arranged in a hounds tooth check pattern or a checkered pattern. Specifically, the patch electrode 108b is arranged in a manner of being spaced apart from the patch electrode 108a by a distance W1 / 2 (W5 / 2) in parallel with the X direction and by a distance W1 / 2 (W5 / 2) in parallel with the Y direction. In addition, in a square formed by connecting the centers O2 of the four patch electrodes 108b around one patch electrode 108a with a line, the intersection of the diagonal lines of the square coincides with the center O1 of one patch electrode 108a. Similarly, in a square formed by connecting the centers O1 of the four patch electrodes 108a around one patch electrode 108b with a line, the intersection of the diagonal lines of the square coincides with the center O2 of one patch electrode 108b.

[0047] In the radio wave reflection device 100a, as an example, the shapes of the plurality of patch electrodes 108a and the shapes of the plurality of patch electrodes 108b are cross-shaped, but the shapes of the plurality of patch electrodes 108a and the shapes of the plurality of patch electrodes 108b are not limited to the cross-shaped. For example, the shapes of the patch electrodes 108a and the shapes of the patch electrodes 108b may be polygons obtained by rotating a square having the same length in the X direction and the Y direction by 45 degrees, or may be rhombuses having four-fold rotational symmetry with respect to the patch electrode 108a and rhombuses having four-fold rotational symmetry with respect to the center O2 of the patch electrode 108b.

[0048] In addition, there is no limitation on the shape of the ground electrode 110. For example, the ground electrode 110 may be shaped as long as it has an area larger than the patch electrode 108a. In the radio wave reflection device 100a, the ground electrode 110 is disposed on the entire surface or substantially the entire surface of the opposing substrate 106 on which the liquid crystal layer 114 is disposed.

[0049] There is no limitation on the material forming the patch electrode 108 and the ground electrode 110. For example, the patch electrode 108 and the ground electrode 110 are formed using a conductive metal or metal oxide.

[0050] In addition, as will be described in detail later, the dielectric substrate 104 may be provided with first wirings 118a and 118b. For example, the first wiring 118a connects the patch electrodes 108a arranged in the same column, and the first wiring 118b connects the patch electrodes 108b arranged in the same column. The first wirings 118a and 118b can be used when applying control signals to the patch electrodes 108a and 108b. In addition, the first wirings 118a and 118b can be used when connecting the patch electrodes 108a and 108b.

[0051] The reflector unit cell 102 is used as a reflector 120 that reflects radio waves in a predetermined direction. Therefore, the reflector unit cell 102 preferably does not attenuate the amplitude of the reflected radio waves as much as possible. Figure 2 to Figure 4 As is clear from the structure shown, when radio waves propagating in the air are reflected by the reflector unit cells 102, the radio waves pass through the dielectric substrate 104 twice. The dielectric substrate 104 is preferably formed of a dielectric material such as glass or resin.

[0052] The dielectric substrate 104 is provided with a sealing material 128 (see Fig.10) is attached to the opposing substrate 106. The dielectric substrate 104 and the opposing substrate 106 are arranged opposite to each other in a manner that a gap is included between the dielectric substrate 104 and the opposing substrate 106. The liquid crystal layer 114 is provided in a region surrounded by the sealing material 128. When viewed from the side, the gap between the dielectric substrate 104 and the opposing substrate 106 is greater than 20 μm and less than 100 μm. In the radio wave reflection device 100a, the gap between the dielectric substrate 104 and the opposing substrate 106 is, for example, 75 μm. A patch electrode 108, a ground electrode 110, a first orientation film 112a, and a second orientation film 112b are provided between the dielectric substrate 104 and the opposing substrate 106. More precisely, the gap between the first orientation film 112a and the second orientation film 112b provided on the dielectric substrate 104 and the opposing substrate 106, respectively, becomes the thickness of the liquid crystal layer 114. Although not shown in the figure, a spacer for maintaining a constant distance between the dielectric substrate 104 and the counter substrate 106 may be provided.

[0053] A control signal for controlling the orientation of the liquid crystal molecules of the liquid crystal layer 114 is applied to the patch electrode 108. The control signal is a DC voltage signal, or a polarity reversal signal in which a positive DC voltage and a negative DC voltage are alternately reversed. A voltage of an intermediate level of the ground or polarity reversal signal is applied to the ground electrode 110. The orientation state of the liquid crystal molecules contained in the liquid crystal layer 114 changes by applying the control signal to the patch electrode 108. A liquid crystal material having dielectric anisotropy is used for the liquid crystal layer 114. For example, nematic liquid crystal, smectic liquid crystal, cholesterol liquid crystal, or discotic liquid crystal is used as the liquid crystal layer 114. The dielectric constant of the liquid crystal layer 114 having dielectric anisotropy changes according to the change in the orientation state of the liquid crystal molecules. The reflector unit cell 102 can change the dielectric constant of the liquid crystal layer 114 according to the control signal applied to the patch electrode 108. As a result, when reflecting radio waves, the phase of the reflected wave can be delayed.

[0054] The frequency band of the radio wave reflected by the reflector unit cell 102 is the very short wave (VHF: Very High Frequency) band, the ultra-short wave (UHF: Ultra-High Frequency) band, the microwave (SHF: Super High Frequency) band, the submillimeter wave (THF: Tremendously high frequency), and the millimeter wave (EHF: Extra High Frequency) band. Millimeter waves are, for example, referred to as the frequency band of 30GHz to 300GHz. In addition, the frequency band of the fifth generation communication standard called 5G includes the 26GHz band to the 29GHz band, and there is a case where the frequencies above the 26GHz band are collectively referred to as millimeter waves. The orientation of the liquid crystal molecules of the liquid crystal layer 114 changes in response to the control signal applied to the patch electrode 108, but hardly follows the frequency of the radio wave incident on the patch electrode 108. Therefore, the reflector unit cell 102 can control the phase of the reflected radio wave without being affected by the radio wave.

[0055] In addition, the plurality of patch electrodes 108a and the plurality of patch electrodes 108b are electrodes capable of reflecting the frequency of radio waves corresponding to the 5G communication standard. The frequency is as described above, for example, a frequency in the millimeter wave band, a frequency above 26 GHz, or a frequency in the range of 26 GHz to 36 GHz.

[0056] Figure 7 A state (referred to as a “first state”) in which no voltage is applied between the patch electrode 108 and the ground electrode 110 is shown. Figure 7 The first and second alignment films 112a and 112b are horizontal alignment films. In the first state, the long axes of the liquid crystal molecules 116 are aligned horizontally with respect to the surfaces of the patch electrode 108 and the ground electrode 110 by the first and second alignment films 112a and 112b. Figure 8 The state (referred to as "second state") in which a control signal (voltage signal) is applied to the patch electrode 108 is shown. In the second state, the liquid crystal molecules 116 are acted upon by the electric field and the long axis is oriented perpendicularly to the surface of the patch electrode 108 and the ground electrode 110. The angle of the long axis orientation of the liquid crystal molecules 116 can also be oriented in a direction intermediate between the horizontal direction and the vertical direction according to the magnitude of the control signal applied to the patch electrode 108 (the magnitude of the voltage between the ground electrode and the patch electrode).

[0057] When the liquid crystal molecules 116 have positive dielectric anisotropy, the dielectric constant of the second state becomes larger than that of the first state. In addition, when the liquid crystal molecules 116 have negative dielectric anisotropy, the apparent dielectric constant of the second state becomes smaller than that of the first state. The liquid crystal layer 114 having dielectric anisotropy can also be regarded as a variable dielectric layer. The reflector unit cell 102 can utilize the dielectric anisotropy of the liquid crystal layer 114 to control the phase of the reflected wave to be delayed (or not delayed).

[0058] Fig. 9 The following schematically shows that the traveling direction of the reflected wave changes due to the arbitrary first subcell 103a and the first subcell 103a adjacent to the arbitrary first subcell 103a. The arbitrary first subcell 103a and the first subcell 103a adjacent to the arbitrary first subcell 103a are adjacent in the X direction. That is, the arbitrary patch electrode 108a and the patch electrode 108a adjacent to the arbitrary patch electrode 108a are connected to different first wirings 118 (first wiring 118a, first wiring 118b). When the radio wave is incident on the arbitrary first subcell 103a and the adjacent first subcell 103a with the same phase, since different control signals (V1≠V2) are applied to the arbitrary first subcell 103a and the adjacent first subcell 103a, the phase change of the reflected wave generated by the arbitrary first subcell 103a is greater than the phase change of the reflected wave generated by the adjacent first subcell 103a. As a result, the phase of the reflected wave R1 reflected by an arbitrary first sub-cell 103a is different from the phase of the reflected wave R2 reflected by the adjacent first sub-cell 103a (in Fig. 9 In the embodiment, the phase of the reflected wave R2 is more advanced than the phase of the reflected wave R1), and the traveling direction of the reflected wave changes in an oblique direction. In addition, in the radio wave reflection device 100a, when the first wiring is distinguished, it is represented as the first wiring 118a and the first wiring 118b, and when the first wiring is not distinguished, it is represented as the first wiring 118.

[0059] Next, the results of simulating the phase change (deg) using the patch electrodes 108a and 108b of the above dimensions in the radio wave reflection device 100a are described. Figure 1 The reflection plates arranged as shown were simulated using CST Studio Suite (manufactured by Dassault Systèmes).

[0060] Although not shown in the figure, in the radio wave reflection device 100a, as an example, it is shown that when the frequency of the radio wave is 31 GHz, the phase change amount in the state where the voltage is applied to the liquid crystal layer is -416 degrees, based on the phase in the state where the voltage is not applied to the liquid crystal layer. On the other hand, as a comparative example, a radio wave reflection device including a square patch electrode is shown, and the result of performing the same simulation as the radio wave reflection device 100a is -270 degrees. That is, using cross-shaped patch electrodes 108a and 108b of different sizes as in the radio wave reflection device 100a is effective in increasing the phase change amount. In addition, although not shown in the figure, for example, by using cross-shaped patch electrodes 108a and 108b of different sizes, it is possible to make two peaks (points with the minimum reflectivity) of the resonance frequency in the millimeter wave band by using the resonance generated in the patch electrode 108a and the resonance generated in the patch electrode 108b, so that the attenuation of the amplitude of the reflected wave can be suppressed and the phase change amount can be increased.

[0061] In addition, if Figure 1 , Figure 5 and Figure 6 As shown, in the radio wave reflection device 100a, by using cross-shaped patch electrodes 108a and 108b of different sizes, the patch electrode 108b with a size smaller than the patch electrode 108a can be arranged at a position away from the patch electrode 108a by a distance W1 / 2 in the X direction and the Y direction. As a result, Figure 1 As shown, the cross-shaped convex portion 109a of the patch electrode 108a and the cross-shaped convex portion 109b of the patch electrode 108b can be alternately arranged along the C1-C2 line parallel to the X direction, and the cross-shaped convex portion 109a of the patch electrode 108a and the cross-shaped convex portion 109b of the patch electrode 108b can be alternately arranged along the C3-C4 line parallel to the Y direction. As a result, the radio wave reflection device 100a can increase the density of the patch electrodes in the reflection plate 120 (the occupancy rate of the patch electrodes in the reflection plate 120, the ratio of the area where the patch electrodes are arranged to the area where the patch electrodes are not arranged in the reflection plate 120) compared with the case where the patch electrodes are arranged in a square shape as in the comparative example. By using the cross-shaped patch electrodes 108a and 108b of different sizes, the area of ​​the electrode that can reflect the radio wave becomes larger, so the reflection intensity of the radio wave can be enhanced.

[0062] Moreover, if Figure 1 , Figure 5 and Figure 6 As shown in FIG. 1 , the plurality of patch electrodes 108a and the plurality of patch electrodes 108b are arranged adjacent to each other. Preferably, the plurality of patch electrodes 108a and the plurality of patch electrodes 108b are arranged adjacent to each other with respect to the center of the reflector unit cell 102 (at Figure 1 , Figure 5 and Figure 6 The center (02) of the patch electrode 108b arranged at the center is arranged twice or four times rotationally symmetrically. By arranging the plurality of patch electrodes 108a and the plurality of patch electrodes 108b twice or four times rotationally symmetrically, it is possible to set the plurality of patch electrodes 108a and 108b to be symmetrical with respect to the vertical polarization wave and the horizontal polarization wave.

[0063] In the radio wave reflection device 100a, as an example, an example is shown in which the reflection plate unit cell 102 includes two types of patch electrodes, the patch electrode 108a and the patch electrode 108b, but the patch electrodes are not limited to two types. The reflection plate unit cell 102 may also include a third patch electrode (not shown) different from the patch electrode 108a and the patch electrode 108b. Here, the size of the third patch electrode is different from the size of the patch electrode 108a and the size of the patch electrode 108b. For example, the size of the third patch electrode may be smaller than the size of the patch electrode 108a, or may be larger than the size of the patch electrode 108b and smaller than the size of the patch electrode 108a. In addition, the third patch electrode may be arranged between the shape of the patch electrode 108a and the patch electrode 108b. In the case where the radio wave reflection device 100a includes the third patch electrode, the size and arrangement of the third patch electrode are appropriately adjusted according to the size and arrangement of the patch electrode 108a and the patch electrode 108b, thereby constituting a radio wave reflection device of one embodiment of the present invention.

[0064] As described above, in the radio wave reflection device 100a, the sizes of the patch electrodes of the reflector unit cell 102 are set to at least two types. The radio wave reflection device 100a using the first embodiment of the present invention is effective in suppressing the attenuation of the amplitude of the reflected wave, increasing the phase change amount, and enhancing the reflection intensity of the radio wave. By using the radio wave reflection device 100a, even when a plurality of radio wave reflection devices 100a are combined to form a transmission path in the air, the attenuation of the radio wave can be suppressed, so that the communication device can perform good communication.

[0065] In addition, in the radio wave reflection device 100a, the patch electrode 108 and the ground electrode 110 are formed using a transparent conductive film, and the liquid crystal layer 114 has light transmittance, so it is possible to reflect radio waves without damaging the lighting. Therefore, the radio wave reflection device 100a can be installed in the window of a high-rise building such as a building. As a result, it is possible to reflect radio waves with high straightness in a predetermined direction at a high place with relatively few obstacles. Therefore, the radio wave reflection device 100a can be used in the urban area to eliminate the quiet zone of radio waves (a place where radio waves cannot reach).

[0066] <2. Radio wave reflection device>

[0067] Next, a description will be given of the structure of a radio wave reflection device 100a in which the reflection plate unit cells 102 are integrated. The radio wave reflection device 100a is a radio wave reflection device capable of performing two-axis reflection control. Fig.10 It is a plan view showing the structure of the radio wave reflection device 100a. Fig.11 Yes Fig.10 The reflector unit cell 102 shown is enlarged to show a top view of the structure of the reflector unit cell 102 . Fig.12 is a cross-sectional view showing a cut surface of the reflector unit cell 102. Figures 1 to 9 The same or similar structures are omitted from description here.

[0068] As described in “1. Reflection plate unit cell”, the reflection plate 120 is provided between the dielectric substrate 104 and the counter substrate 106. Fig.10 As shown, the reflector 120 has a structure in which a plurality of reflector units 102 are integrated. The reflector unit 102 includes a first sub-unit 103a and a second sub-unit 103b. For example, the plurality of reflector units 102 (a plurality of first sub-units 103a and a plurality of second sub-units 103b) are arranged along the X direction and the Y direction. The first sub-unit 103a includes a ground electrode 110, a second orientation film 112b arranged on the ground electrode 110, a patch electrode 108a, a first orientation film 112a arranged on the patch electrode 108a, an array layer 180, and a liquid crystal layer (not shown) provided between the first orientation film 112a and the second orientation film 112b. In addition, the second subcell 103b includes a ground electrode 110, a second orientation film 112b disposed on the ground electrode 110, a patch electrode 108b, a first orientation film 112a disposed on the patch electrode 108b, an array layer 180, and a liquid crystal layer (not shown) disposed between the first orientation film 112a and the second orientation film 112b. The patch electrodes 108a and 108b are disposed on the array layer 180 disposed on the dielectric substrate 104, and the ground electrode 110 is disposed on the counter substrate 106. In addition, the dielectric substrate 104 is bonded to the counter substrate 106 using a sealing material 128. The liquid crystal layer is disposed in the inner region of the sealing material 128.

[0069] In the reflector unit cell 102, the patch electrodes 108a and 108b are arranged facing the incident surface of the radio wave. The ground electrode 110 is a flat plate. The plurality of patch electrodes 108a and 108b are arranged in a matrix in the surface of the flat ground electrode 110 and in the region inside the sealing material 128.

[0070] As described in "1. Reflector Cell", when the radio wave reflection device 100a is viewed from above, the plurality of patch electrodes 108a and the plurality of patch electrodes 108b are arranged in a houndstooth pattern or a checkerboard pattern. Specifically, the patch electrode 108b is arranged in a manner parallel to the X direction and away from the patch electrode 108a by a distance W1 / 2 (W5 / 2), and parallel to the Y direction and away from the patch electrode 108a by a distance W1 / 2 (W5 / 2). In addition, each patch electrode 108a is adjacent to each patch electrode 108b in the X direction or the Y direction.

[0071] A plurality of first wirings 118a and a plurality of first wirings 118b extending in the Y direction are arranged on the dielectric substrate 104. The first wirings 118a and the first wirings 118b are arranged alternately in the X direction. The plurality of first wirings 118a are electrically connected to the plurality of patch electrodes 108a arranged in the second direction, respectively, and the plurality of first wirings 118b are electrically connected to the plurality of patch electrodes 108b arranged in the second direction, respectively. The reflector 120 has a structure in which a plurality of patch electrode arrays connected by the first wirings 118a and 118b are arranged in the Y direction.

[0072] In addition, a plurality of second wirings 132a and a plurality of second wirings 132b extending in the X direction are arranged on the dielectric substrate 104. The second wirings 132a and the second wirings 132b are arranged alternately in the Y direction. The plurality of second wirings 132a are electrically connected to the plurality of patch electrodes 108a arranged in the second direction, respectively, and the plurality of second wirings 132b are electrically connected to the plurality of patch electrodes 108b arranged in the second direction, respectively. The reflector 120 has a structure in which a plurality of patch electrode arrays connected by the second wirings 132a and the second wirings 132b are arranged in the X direction.

[0073] In the dielectric substrate 104, the area other than the area where the reflector 120 is provided is referred to as a peripheral area 122. The peripheral area 122 is provided with a first drive circuit 124 and a terminal portion 126. The terminal portion 126 is an area where a connection with an external circuit is formed, and for example, a flexible printed circuit is connected to the terminal portion 126 (not shown). A signal for controlling the first drive circuit 124 is input from the flexible printed circuit to the terminal portion 126.

[0074] The plurality of first wirings 118a and 118b disposed on the reflector 120 extend in the Y-axis direction and extend to the peripheral region 122, and are connected to the first drive circuit 124. The first drive circuit 124 outputs a control signal to the patch electrodes 108a and 108b via the first wirings 118a and 118b. The first drive circuit 124 can output control signals of different voltage levels to the plurality of first wirings 118a and 118b, respectively. The control signals of different voltage levels are, for example, a control signal of the first voltage level and a control signal during the second voltage level.

[0075] The plurality of second wirings 132a and 132b extending in the X direction and arranged on the reflector 120 extend in the X direction and are connected to the second drive circuit 130. The second drive circuit 130 outputs a scanning signal to the plurality of second wirings 132a and 132b.

[0076] Fig.11 The diagram shows an enlarged arrangement of two patch electrodes 108a and two patch electrodes 108b, first wirings 118a and 118b, and second wirings 132a and 132b. Switching elements 134 are provided at the two patch electrodes 108a and the two patch electrodes 108b, respectively. The switching (on and off) of the switching elements 134 is controlled by the scanning signal applied to the second wirings 132a and 132b. According to the scanning signal applied to the second wiring 132a, the patch electrode 108a turned on by the switching element 134 is conducted with the first wiring 118a and a control signal is applied. In addition, according to the scanning signal applied to the second wiring 132b, the patch electrode 108b turned on by the switching element 134 is conducted with the first wiring 118b and a control signal is applied. The switching element 134 is formed of, for example, a thin film transistor. According to such a configuration, a plurality of patch electrodes 108 a and 108 b arranged in the X direction can be selected row by row, and control signals having different voltage levels can be applied to the respective rows.

[0077] The radio wave reflection device 100a can control the traveling direction of the reflected wave in the left-right direction of the drawing with the reflection axis VR parallel to the Y direction as the center for the radio wave incident on the reflection plate 120, and on this basis, can also control the traveling direction of the reflected wave in the up-down direction of the drawing with the reflection axis HR parallel to the X direction as the center for the radio wave incident on the reflection plate 120. That is, the radio wave reflection device 100a includes a reflection axis VR parallel to the Y direction and a reflection axis VH parallel to the X direction, and can control the reflection angle in the direction in which the reflection axis VR is set as the rotation axis and in the direction in which the reflection axis HR is set as the rotation axis.

[0078] In addition, Fig.10 In the example of the radio wave reflection device 100a shown in FIG. 1 , a patch electrode 108a is arranged parallel to the X direction on the side far from the first drive circuit 124 in the Y direction, and a patch electrode 108b is arranged parallel to the X direction on the side close to the first drive circuit 124. Fig.10 In the example of the radio wave reflection device 100a shown in FIG. 1 , the patch electrode 108a is arranged parallel to the Y direction on the side far from the second driving circuit 130 in the X direction, and the patch electrode 108b is arranged parallel to the Y direction on the side close to the second driving circuit 130. The arrangement of the patch electrodes 108a and 108b is not limited to Fig.10. For example, the patch electrode 108b may be arranged parallel to the X direction on the side far from the first drive circuit 124, and the patch electrode 108a may be arranged parallel to the X direction on the side close to the first drive circuit 124. In addition, the patch electrode 108b may be arranged parallel to the Y direction on the side far from the second drive circuit 130, and the patch electrode 108b may be arranged parallel to the Y direction on the side close to the second drive circuit 130. The structure of the radio wave reflection device 100a is not limited as long as it includes a structure for controlling the reflection angle in the direction in which the reflection axis VR is set as the rotation axis and in the direction in which the reflection axis HR is set as the rotation axis.

[0079] Fig.12 An example of a cross-sectional structure of a reflector unit cell 102 in which a switch element 134 is connected to a patch electrode 108 is shown. The reflector unit cell 102 includes a first sub-cell 103a and a second sub-cell 103b, and the cross-sectional surface of the first sub-cell 103a is the same as the cross-sectional surface of the second sub-cell 103b. Here, the cross-sectional surface of the first sub-cell 103a is mainly described. The switch element 134 is provided on the dielectric substrate 104. The switch element 134 is a transistor. The switch element 134 includes a structure in which a first gate electrode 138, a second gate insulating layer 146, a semiconductor layer 142, a second gate insulating layer 146, and a second gate electrode 148 are stacked. A primer layer 136 may be provided between the first gate electrode 138 and the dielectric substrate 104. A first wiring 118a is provided between the first gate insulating layer 140 and the second gate insulating layer 146. The first wiring 118a is provided in contact with the semiconductor layer 142. In addition, a first connection wiring 144 is provided in the same conductive layer as the conductive layer forming the first wiring 118a. The first connection wiring 144 is provided in contact with the semiconductor layer 142. Regarding the connection structure of the first wiring 118a and the first connection wiring 144 with respect to the semiconductor layer 142, a structure in which one wiring is connected to the source of the transistor and the other wiring is connected to the drain is shown.

[0080] The first interlayer insulating layer 150 is provided so as to cover the switch element 134. The second wiring 132a is provided on the first interlayer insulating layer 150. The second wiring 132a is connected to the second gate electrode 148 via a contact hole formed in the first interlayer insulating layer 150. In addition, although not shown, the first gate electrode 138 and the second gate electrode 148 are electrically connected to each other in a region that does not overlap with the semiconductor layer 142. On the first interlayer insulating layer 150, a second connection wiring 152 is provided on the same conductive layer as the second wiring 132a. The second connection wiring 152 is connected to the first connection wiring 144 via a contact hole formed in the first interlayer insulating layer 150.

[0081] The second interlayer insulating layer 154 is provided so as to cover the second wiring 132a and the second connection wiring 152. Furthermore, the planarizing layer 156 is provided so as to fill in the level difference generated by the formation of the switching element 134. By providing the planarizing layer 156, the level difference of the switching element 134 can be filled in, so that the surface of the planarizing layer 156 becomes flat. Thus, the patch electrode 108a can be formed on the flat surface (surface) of the planarizing layer 156 without being affected by the level difference of the switching element 134. The passivation layer 158 is provided on the flat surface of the planarizing layer 156. In the radio wave reflection device 100a, the array layer 180 includes, for example, a primer layer 136, a conductive layer including a first gate electrode 138, a first gate insulating layer 140, a semiconductor layer 142, a conductive layer including a first connection wiring 144, a second gate insulating layer 146, a conductive layer including a second gate electrode 148, a first interlayer insulating layer 150, a conductive layer including a second connection wiring 152, a second interlayer insulating layer 154, a planarizing layer 156, and a passivation layer 158. The array layer 180 may also include a conductive layer of a patch electrode 108 formed at a contact hole penetrating the passivation layer 158, the planarizing layer 156, and the second interlayer insulating layer 154.

[0082] The patch electrode 108 is provided on the passivation layer 158. The patch electrode 108 is connected to the second connection wiring 152 via a contact hole penetrating the passivation layer 158, the planarization layer 156, and the second interlayer insulating layer 154. On the patch electrode 108, a first alignment film 112a is provided.

[0083] On the counter substrate 106, Figure 2 to Figure 4 The structure of the cross-section shown in FIG. 1 is similar to that of the cross-section shown in FIG. 1 , and a ground electrode 110 and a second orientation film 112b are provided. The surface of the dielectric substrate 104 provided with the switching element 134 and the patch electrode 108a is arranged to be opposite to the surface of the counter substrate provided with the ground electrode 110, and a liquid crystal layer 114 is provided between the surface provided with the switching element 134 and the patch electrode 108a and the surface provided with the ground electrode 110. The thickness T of the dielectric substrate 104 can be set to be the length from the surface of the patch electrode 108a on the liquid crystal layer 114 side to the surface of the dielectric substrate 104 on the opposite side to the surface provided with the patch electrode 108. In this case, the thickness of at least one insulating layer (primer layer 136, first gate insulating layer 140, second gate insulating layer 146, first interlayer insulating layer 150, second interlayer insulating layer 154, planarizing layer 156, passivation layer 158) between the patch electrode 108 and the dielectric substrate 104 can also be considered.

[0084] Each layer formed on the dielectric substrate 104 is formed using the following materials. The base coat 136 is formed of, for example, a silicon oxide film. The first gate insulating layer 140 and the second gate insulating layer 146 are formed of, for example, a silicon oxide film or a stacked structure of a silicon oxide film and a silicon nitride film. The semiconductor layer is formed of a silicon semiconductor such as amorphous silicon and polycrystalline silicon, and an oxide semiconductor containing metal oxides such as indium oxide, zinc oxide, and gallium oxide. The first gate electrode 138 and the second gate electrode 148 can be formed of, for example, molybdenum (Mo), tungsten (W) or their alloys. The first wiring 118, the second wiring 132, the first connecting wiring 144 and the second connecting wiring 152 are formed using metal materials such as titanium (Ti), aluminum (Al), and molybdenum (Mo). For example, it can be composed of a stacked structure of titanium (Ti) / aluminum (Al) / titanium (Ti), or a stacked structure of molybdenum (Mo) / aluminum (Al) / molybdenum (Mo). The planarization layer 156 is formed of a resin material such as acrylic resin and polyimide. The passivation layer 158 is formed of, for example, a silicon nitride film, etc. The patch electrode 108a and the ground electrode 110 are formed of a metal film such as aluminum (Al) or copper (Cu), or a transparent conductive film such as indium tin oxide (ITO).

[0085] like Fig.12 As shown, by connecting the second wiring 132a to the gate of the transistor used as the switching element 134, connecting the first wiring 118a to one of the source and drain of the transistor, and connecting the patch electrode 108a to the other of the source and drain, it is possible to select a predetermined patch electrode from a plurality of patch electrodes 108a arranged in a matrix and apply a control signal. Furthermore, by providing the switching element 134 to each patch electrode 108a in the reflector 120, it is possible to apply a control voltage to each patch electrode 108a arranged in a horizontal row parallel to the X direction, or to each patch electrode 108a arranged in a vertical row parallel to the Y direction. For example, when the reflector 120 is upright, the reflection direction of the reflected wave can be controlled in the left-right direction and the up-down direction.

[0086] Furthermore, in the second sub-cell 103b, the patch electrode 108a, the first wiring 118a, and the second wiring 132a are replaced with the patch electrode 108b, the first wiring 118b, and the second wiring 132b.

[0087] <Second Embodiment>

[0088] In the second embodiment, as an example, a radio wave reflection device 100b capable of uniaxial reflection control is described. The reflection axis RY of the radio wave reflection device 100b is uniaxial. In the radio wave reflection device 100b, the reflection angle can be controlled in the direction in which the reflection axis RY is set as the rotation axis. The radio wave reflection device 100b of the second embodiment does not include at least the array layer 180, the plurality of second wirings 132a and the plurality of second wirings 132b, and the second driving circuit 130 relative to the radio wave reflection device 100a of the first embodiment. In the second embodiment, the difference from the first embodiment is mainly described.

[0089] Fig.13 It is a plan view showing the structure of a radio wave reflection device 100b according to the second embodiment. Fig.14 1 is a plan view showing a reflector unit cell 102b used in the radio wave reflection device 100b. Fig.15 Yes means Fig.14 The cross-sectional view of the cut surface along the D1-D2 line shown, Fig.16 Yes means Fig.14 The cross-sectional view of the section plane of the E1-E2 line shown. Figures 1 to 12 The same or similar structures are omitted from description here.

[0090] like Fig.13 As shown in FIG. 1 , the reflector 120 of the second embodiment includes a plurality of reflector units 102 b. The reflector 120 of the second embodiment includes a structure in which the plurality of reflector units 102 of the reflector 120 of the first embodiment are replaced with a plurality of reflector units 102 b.

[0091] like Fig.13 and Fig.14As shown, a plurality of patch electrodes 108a arranged in the Y direction are electrically connected to the first wiring 118a, and a plurality of patch electrodes 108b arranged in the Y direction are electrically connected to the first wiring 118b. In the reflector 120 of the second embodiment, a plurality of patch electrodes 108a electrically connected to the first wiring 118a and a plurality of patch electrodes 108b electrically connected to the first wiring 118b are set as a set of voltage applying units 190a, and a plurality of sets of voltage applying units 190a are arranged in the X direction. The first wiring 118a is electrically connected to the first wiring 118b in the peripheral region 122. In addition, in the reflector 120 of the second embodiment, the voltage applying unit 190b includes the same structure as the voltage applying unit 190a, and the voltage applying units 190a and the voltage applying units 190b are alternately arranged in the X direction. There is a case where the first wiring 118a contained in the voltage applying unit 190a is called the 1-1 wiring, the first wiring 118b contained in the voltage applying unit 190a is called the 1-2 wiring, the first wiring 118a contained in the voltage applying unit 190b is called the 1-3 wiring, and the first wiring 118b contained in the voltage applying unit 190b is called the 1-4 wiring.

[0092] Similar to the reflector 120 described in “1. Reflector Cell”, the reflector 120 of the second embodiment is provided between the dielectric substrate 104 and the counter substrate 106. Fig.13 and Fig.14 As shown in FIG. 1 , the reflector 120 of the second embodiment has a structure in which a plurality of reflector units 102 b are integrated. Similar to the reflector unit unit 102 , the reflector unit unit 102 b includes a first sub-unit unit 103 a and a second sub-unit unit 103 b .

[0093] like Fig.15 and Fig.16 As shown, the first sub-cell 103a includes a ground electrode 110, a second orientation film 112b disposed on the ground electrode 110, a patch electrode 108a, a first orientation film 112a disposed on the patch electrode 108a, and a liquid crystal layer 114 disposed between the first orientation film 112a and the second orientation film 112b. In addition, the second sub-cell 103b includes a ground electrode 110, a second orientation film 112b disposed on the ground electrode 110, a patch electrode 108b, a first orientation film 112a disposed on the patch electrode 108b, and a liquid crystal layer (not shown) disposed between the first orientation film 112a and the second orientation film 112b. The patch electrodes 108a and 108b are disposed on the dielectric substrate 104, and the ground electrode 110 is disposed on the counter substrate 106. In addition, the dielectric substrate 104 is bonded to the counter substrate 106 using a sealing material 128. The liquid crystal layer is provided in a region inside the sealant 128 .

[0094] In the reflector unit cell 102b, the patch electrodes 108a and 108b are arranged facing the incident surface of the radio wave. The ground electrode 110 is a flat plate. The plurality of patch electrodes 108a and 108b are arranged in a matrix in the region inside the sealing material 128 within the plane of the flat ground electrode 110.

[0095] The plurality of first wirings 118a and 118b disposed on the reflector 120 of the second embodiment extend to the peripheral region 122 and are connected to the first drive circuit 124. The first drive circuit 124 outputs control signals to the patch electrodes 108a and 108b via the first wirings 118a and 118b. As a result, in the reflector 120, the control signals are applied to the patch electrodes 108a and 108b disposed in the X direction and the Y direction, and to the patch electrodes 108a and 108b disposed in the Y direction.

[0096] In the radio wave reflection device 100b, the first driving circuit 124 can apply a control signal to each voltage applying unit 190a (voltage applying unit 190b) arranged in the second direction. The reflection direction of the reflected wave of the radio wave incident on the reflector 120 can be controlled for each voltage applying unit 190a (voltage applying unit 190b) arranged in the second direction. That is, in the radio wave reflection device 100a, the first driving circuit 124 can apply (supply) different voltages (first voltage and second voltage) to the voltage applying unit 190a and the voltage applying unit 190b, and therefore, the traveling direction of the reflected wave of the radio wave incident on the reflector 120 can be controlled in the left and right directions of the drawing with the reflection axis VR parallel to the Y direction as the center.

[0097] The plurality of patch electrodes 108a and 108b arranged along the second direction in one voltage applying unit 190a (voltage applying unit 190b) are electrically connected in the peripheral region 122 using the first wirings 118a and 118b to be electrically equipotential. Fig.13 As shown, the patch electrodes 108a and the patch electrodes 108b are set to be symmetrical with respect to the vertical polarization wave and the horizontal polarization wave and are arranged in an array, and a plurality of patch electrodes 108a and a plurality of patch electrodes 108b arranged parallel to the reflection axis RY are connected with the first wiring 118a and the first wiring 118b. Thus, the traveling direction of the reflected wave of the radio wave incident on the reflecting plate 120 can be controlled in the left and right directions of the drawing with the reflection axis VR parallel to the Y direction as the center.

[0098] As one embodiment of the present invention, the various structures of the radio wave reflection device and the reflection plate unit illustrated can be appropriately combined as long as they do not contradict each other. In addition, the scheme obtained by the technicians in this specification and the radio wave reflection device and the reflection plate unit disclosed in the drawings appropriately adding, deleting or changing the design of the components, or the scheme obtained by adding, omitting or changing the conditions of the process is also included in the scope of the present invention as long as it has the gist of the present invention.

[0099] Even if there are other effects different from the effects brought about by the scheme of the implementation method disclosed in this specification, the effects that are clear from the description of this specification or the effects that are easily anticipated by those skilled in the art are of course interpreted as being brought about by the present invention.

[0100] Description of Reference Numerals

[0101] 100a: radio wave reflecting device, 100b: radio wave reflecting device, 102: reflecting plate unit cell, 102b: reflecting plate unit cell, 103a: first sub-unit cell, 103b: second sub-unit cell, 104: dielectric substrate, 106: opposing substrate, 108: patch electrode, 108a: patch electrode, 108b: patch electrode, 109a: convex portion, 109b: convex portion, 110: ground electrode, 112a: first orientation film, 112b: second orientation film, 114: liquid crystal layer, 116: liquid crystal molecules, 118: first wiring, 118a: first wiring, 118b: first wiring, 120: reflecting plate, 122: peripheral area, 124 : 1st driving circuit, 126: terminal part, 128: sealing material, 130: 2nd driving circuit, 132: 2nd wiring, 132a: 2nd wiring, 132b: 2nd wiring, 134: switching element, 136: primer layer, 138: 1st gate electrode, 140: 1st gate insulating layer, 142: semiconductor layer, 144: 1st connecting wiring, 146: 2nd gate insulating layer, 148: 2nd gate electrode, 150: 1st interlayer insulating layer, 152: 2nd connecting wiring, 154: 2nd interlayer insulating layer, 156: planarization layer, 158: passivation layer, 180: array layer, 190a: voltage applying unit, 190b: voltage applying unit.

Claims

1. A radio wave reflection device, wherein: include: A plurality of first patch electrodes; a plurality of second patch electrodes having a size different from that of the plurality of first patch electrodes; a ground electrode, which is opposite to the plurality of first patch electrodes and the plurality of second patch electrodes and is disposed separately from the plurality of first patch electrodes and the plurality of second patch electrodes; and a liquid crystal layer provided between the plurality of first patch electrodes, the plurality of second patch electrodes and the ground electrode, In a plan view, the plurality of first patch electrodes and the plurality of second patch electrodes are arranged in a matrix in a first direction and a second direction intersecting the first direction. When the distance between the centers of two adjacent first patch electrodes is set to distance W1, the second patch electrode is arranged at a position that is away from the first patch electrode by a distance W1 / 2 parallel to the first direction and by a distance W1 / 2 parallel to the second direction, with reference to the position of the first patch electrode.

2. The radio wave reflection device according to claim 1, wherein: In a square formed by connecting the centers of four second patch electrodes adjacent to one of the plurality of first patch electrodes with a line, The intersection point of the diagonal lines of the square coincides with the center of the one first patch electrode.

3. The radio wave reflection device according to claim 1, wherein: In a square formed by connecting the centers of four first patch electrodes adjacent to one of the plurality of second patch electrodes with a line, The intersection point of the diagonal lines of the square coincides with the center of the one second patch electrode.

4. The radio wave reflection device according to claim 1, wherein: The size of the plurality of first patch electrodes is larger than the size of the plurality of second patch electrodes.

5. The radio wave reflection device according to claim 1, wherein: The shapes of the plurality of first patch electrodes and the plurality of second patch electrodes are cross-shaped in a plan view.

6. The radio wave reflection device according to claim 1, wherein: The plurality of first patch electrodes and the plurality of second patch electrodes are arranged in a checkerboard pattern.

7. The radio wave reflection device according to claim 6, wherein: Also includes: a 1-1 wiring electrically connected to at least two of the plurality of first patch electrodes; a 1-2 wiring electrically connected to at least two of the plurality of second patch electrodes and arranged in parallel with the 1-1 wiring; and a driving circuit electrically connected to the 1-1 wiring and the 1-2 wiring, The driving circuit supplies a first voltage to the 1-1 wiring and the 1-2 wiring.

8. The radio wave reflection device according to claim 7, wherein: Also includes: a 1-3 wiring electrically connected to at least two first patch electrodes different from the at least two first patch electrodes among the plurality of first patch electrodes and arranged in parallel with the 1-2 wiring; and a 1-4 wiring electrically connected to at least two second patch electrodes different from the at least two second patch electrodes among the plurality of second patch electrodes and arranged in parallel with the 1-3 wiring, The 1-3 wiring and the 1-4 wiring are electrically connected to the driving circuit. The driving circuit supplies a second voltage different from the first voltage to the 1-3 wiring and the 1-4 wiring.

9. The radio wave reflection device according to claim 1, wherein: The plurality of first patch electrodes and the plurality of second patch electrodes are each electrically connected to a switching element.

10. The radio wave reflection device according to claim 1, wherein: The plurality of first patch electrodes and the plurality of second patch electrodes are capable of reflecting the frequency of radio waves corresponding to the 5G communication standard.

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