Electromagnetic wave modulation device

Abstract

An electromagnetic wave modulation device includes a liquid crystal antenna device and a first metasurface structure disposed on a first side of the liquid crystal antenna device. The liquid crystal antenna device includes a first antenna electrode, a second antenna electrode, a first common electrode, a second common electrode and a liquid crystal layer. The liquid crystal layer is located between the first antenna electrode and the first common electrode and between the second antenna electrode and the second common electrode. The first metasurface structure includes a first auxiliary electrode, a second auxiliary electrode, a first counter electrode, a second counter electrode and a first dielectric layer. The first dielectric layer is located between the first auxiliary electrode and the first counter electrode and between the second auxiliary electrode and the second counter electrode. The dielectric constant of the first dielectric layer is a fixed value.

Description

[Technical Field]

[0001] This invention relates to an electromagnetic wave modulation device. [Previous Technology]

[0002] With the accelerated commercialization of fifth-generation mobile communication technology (5G), applications such as remote medical care, VR live streaming, 4K ultra-high-definition live streaming, and smart homes have ushered in unprecedented development opportunities. Leveraging its superior performance in high data transmission rates, low latency, high energy efficiency, low cost, increased system capacity, and support for large-scale device connections, 5G technology has promoted cross-industry collaboration, jointly driving the construction of a new generation of 5G ecosystem. To further improve the coverage of 5G millimeter wave technology, various advanced antenna technologies have emerged, including reflective antennas and penetrating array antennas.

[0003] Penetrating array antennas are a key technology. Their core feature is that they allow electromagnetic waves to penetrate the antenna structure and propagate, thereby achieving multi-directional and multi-angle signal coverage. These antennas are typically installed on the exterior windows of buildings (exterior windows), enabling them to directly receive electromagnetic wave signals from base stations outside the building and redirect the signals to the location of indoor users. The application of penetrating array antennas not only improves the coverage range of 5G millimeter waves but also provides a reliable solution to overcome the shielding effect of building walls on indoor signals. [Summary of the Invention]

[0004] The present invention provides an electromagnetic wave modulation device, which has the advantage of large phase modulation.

[0005] At least one embodiment of the present invention provides an electromagnetic wave modulation device, which includes a liquid crystal antenna device and a first metasurface structure disposed on a first side of the liquid crystal antenna device. The liquid crystal antenna device includes a first antenna electrode, a second antenna electrode, a first common electrode, a second common electrode, and a liquid crystal layer. The first antenna electrode and the second antenna electrode are respectively located in a first liquid crystal control region and a second liquid crystal control region of the liquid crystal antenna device. The first common electrode and the second common electrode are respectively located in the first liquid crystal control region and the second liquid crystal control region of the liquid crystal antenna device. The first common electrode includes a first opening overlapping the first antenna electrode, and the second common electrode includes a second opening overlapping the second antenna electrode. The liquid crystal layer is located between the first antenna electrode and the first common electrode and between the second antenna electrode and the second common electrode. The first metasurface structure includes a first auxiliary electrode, a second auxiliary electrode, a first opposing electrode, a second opposing electrode, and a first dielectric layer. The first auxiliary electrode and the second auxiliary electrode are respectively overlapping the first liquid crystal control region and the second liquid crystal control region of the liquid crystal antenna device. The first opposing electrode includes a first through-hole overlapping the first auxiliary electrode, and the second opposing electrode includes a second through-hole overlapping the second auxiliary electrode. The first dielectric layer is located between the first auxiliary electrode and the first counter electrode, and between the second auxiliary electrode and the second counter electrode. The dielectric constant of the first dielectric layer is a fixed value.

Implementation Method

[0006] FIG1 is a schematic diagram of an electromagnetic wave modulation device 10A according to an embodiment of the present invention. Referring to FIG1, in this embodiment, the electromagnetic wave modulation device 10A is a penetrating array antenna, which includes a plurality of antenna elements AU arranged in an array. In some embodiments, the electromagnetic wave modulation device 10A is disposed on the outer surface of a building, the outer surface of a vehicle, or other suitable locations. In some embodiments, the electromagnetic wave modulation device 10A is disposed on a window of a building or vehicle, and visible light can also pass through the electromagnetic wave modulation device 10A, in addition to electromagnetic wave signals emitted by the base station 30.

[0007] The controller 20 is electrically connected to the electromagnetic wave modulation device 10A and is used to control the liquid crystal antenna device in the electromagnetic wave modulation device 10A. The liquid crystal antenna device will be described in conjunction with the following embodiments.

[0008] The electromagnetic wave modulation device 10A is used to perform beam control on the electromagnetic wave signal emitted by the base station 30, thereby improving the coverage of the electromagnetic wave signal in the room (or vehicle). Therefore, the electronic devices 40 in the room (or vehicle) can receive signals from more angles.

[0009] FIG2A is a schematic cross-sectional view of an electromagnetic wave modulation device 10A according to an embodiment of the present invention. Specifically, FIG2A shows a schematic cross-sectional view of one of the antenna elements AU of the electromagnetic wave modulation device 10A. However, in practice, the electromagnetic wave modulation device 10A may include an array of multiple antenna elements AU, as shown in FIG1. ​​FIG2B to FIG2C are respectively top views of a first metasurface structure 200A, a liquid crystal antenna device 100A, and a second metasurface structure 300A according to an embodiment of the present invention.

[0010] Referring to FIG. 2A, the electromagnetic wave modulation device 10A includes a liquid crystal antenna device 100A and a first metasurface structure 200A disposed on a first side 102 of the liquid crystal antenna device 100A. In this embodiment, the electromagnetic wave modulation device 10A further includes a second metasurface structure 300A disposed on a second side 104 of the liquid crystal antenna device 100A opposite to the first side 102. The liquid crystal antenna device 100A is located between the first metasurface structure 200A and the second metasurface structure 300A.

[0011] Referring to Figures 2A and 2C, the liquid crystal antenna device 100A includes a first antenna electrode 112, a second antenna electrode 114, a first common electrode 122, a second common electrode 124, and a liquid crystal layer 130. In this embodiment, the liquid crystal antenna device 100A further includes a first substrate 140, a second substrate 150, and an active element layer 160.

[0012] The first substrate 140 and the second substrate 150 include glass, organic polymer or other materials that electromagnetic waves can penetrate.

[0013] An active element layer 160 is disposed on the first substrate 140 and includes a first active element 162 and a second active element 164. The first active element 162 and the second active element 164 are, for example, thin-film transistors.

[0014] The first antenna electrode 112 and the second antenna electrode 114 are located on the active element layer 160 and are electrically connected to the first active element 162 and the second active element 164, respectively. In this embodiment, the first antenna electrode 112 and the second antenna electrode 114 are located in the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A, respectively. In FIG. 2A, the first active element 162 and the second active element 164 are only for illustration, and their positions can be adjusted as needed. For example, in order to reduce the interference of the signals operating the first active element 162 and the second active element 164 on the antenna radiation, the positions of the first active element 162 and the second active element 164 are adjusted so that the first active element 162 and the second active element 164 are not directly located below the first antenna electrode 112 and the second antenna electrode 114, thereby increasing the lateral distance between the first active element 162 and the first antenna electrode 112 and the lateral distance between the second active element 164 and the second antenna electrode 114.

[0015] In some embodiments, the shape of the first antenna electrode 112 is equal to the shape of the second antenna electrode 114. In some embodiments, the first antenna electrode 112 and the second antenna electrode 114 each have a symmetrical shape, such as a square, a circle, a hexagon, etc.

[0016] In this embodiment, the size of the first antenna electrode 112 is not equal to the size of the second antenna electrode 114. In other words, the length PL1a and width PW1a of the first antenna electrode 112 are the same as or different from the length PL1b and width PW1b of the second antenna electrode 114. In this embodiment, the length PL1a is equal to the width PW1a and is in the range of 300 micrometers to 600 micrometers, for example, 455 micrometers; the length PL1b is equal to the width PW1b and is in the range of 350 micrometers to 650 micrometers, for example, 472.5 micrometers. In this embodiment, the length PL1b and width PW1b of the second antenna electrode 114 are greater than the length PL1a and width PW1a of the first antenna electrode 112.

[0017] The first common electrode 122 and the second common electrode 124 are respectively located in the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A. The first common electrode 122 includes a first opening 122h that overlaps with the first antenna electrode 112, and the second common electrode 124 includes a second opening 124h that overlaps with the second antenna electrode 114.

[0018] In this embodiment, the first common electrode 122 and the second common electrode 124 are electrically connected to each other. For example, both are simultaneously electrically connected to ground voltage or other reference voltage. In some embodiments, in order to improve the transmittance of the liquid crystal antenna device 100A for visible light, the first common electrode 122, the second common electrode 124, or the space between them are designed to allow more visible light to pass through.

[0019] In some embodiments, the shape of the first opening 122h is equal to the shape of the second opening 124h. In this embodiment, both the first opening 122h and the second opening 124h are cross-shaped, which can correspond to horizontal polarization signals and vertical polarization signals. In other embodiments, the first opening 122h and the second opening 124h have other shapes. For example, in this embodiment, the four endpoints of the cross shape are arc-shaped, but the invention is not limited thereto. In other embodiments, the four endpoints of the cross shape are rectangular, trapezoidal, or other symmetrical shapes. When the four endpoints of the cross shape are trapezoidal, its shape resembles two bow ties overlapping each other perpendicularly.

[0020] In some embodiments, the size of the first opening 122h is equal to the size of the second opening 124h. For example, the width SL1a of the first opening 122h and the width SL1b of the second opening 124h are 950 micrometers to 1350 micrometers, such as 1136 micrometers. For example, the first opening 122h and the second opening 124h each include four extensions extending outward from the center, and the width SW1a of the extension of the first opening 122h and the width SW1b of the extension of the second opening 124h are 150 micrometers to 450 micrometers, such as 236 micrometers.

[0021] The liquid crystal layer 130 is located between the first substrate 140 and the second substrate 150. The liquid crystal layer 130 is located between the first antenna electrode 112 and the first common electrode 122, and between the second antenna electrode 114 and the second common electrode 124. In this embodiment, the liquid crystal molecules in the liquid crystal layer 130 in the first liquid crystal control region X1 can be controlled by the electric field between the first antenna electrode 112 and the first common electrode 122, thereby changing the dielectric constant of the liquid crystal layer 130 in the first liquid crystal control region X1. On the other hand, the liquid crystal molecules in the liquid crystal layer 130 in the second liquid crystal control region X2 can be controlled by the electric field between the second antenna electrode 114 and the second common electrode 124, thereby changing the dielectric constant of the liquid crystal layer 130 in the second liquid crystal control region X2. The liquid crystal layer 130 in the first liquid crystal control region X1 and the liquid crystal layer 130 in the second liquid crystal control region X2 can be controlled separately, so that the liquid crystal layer 130 has the same or different dielectric constants in the first liquid crystal control region X1 and the second liquid crystal control region X2.

[0022] Please refer to Figures 2A and 2B. The first metasurface structure 200A includes a first auxiliary electrode 212, a second auxiliary electrode 214, a first opposing electrode 222, a second opposing electrode 224, and a first dielectric layer 230.

[0023] The first auxiliary electrode 212 and the second auxiliary electrode 214 are respectively superimposed on the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A. In this embodiment, the first auxiliary electrode 212 and the second auxiliary electrode 214 are respectively superimposed on the first antenna electrode 112 and the second antenna electrode 114.

[0024] In some embodiments, the shape of the first auxiliary electrode 212 is equal to the shape of the second auxiliary electrode 214. In some embodiments, the first auxiliary electrode 212 and the second auxiliary electrode 214 each have a symmetrical shape, such as a square, a circle, a hexagon, etc.

[0025] In this embodiment, the size of the first auxiliary electrode 212 is not equal to the size of the second auxiliary electrode 214. In other words, the length PL2a and width PW2a of the first auxiliary electrode 212 are the same as or different from the length PL2b and width PW2b of the second auxiliary electrode 214. In this embodiment, the length PL2a is equal to the width PW2a and is in the range of 600 micrometers to 1000 micrometers, for example, 835 micrometers; the length PL2b is equal to the width PW2b and is in the range of 700 micrometers to 1100 micrometers, for example, 870 micrometers. In this embodiment, the length PL2b and width PW2b of the second auxiliary electrode 214 are greater than the length PL2a and width PW2a of the first auxiliary electrode 212, and the length PL2a and width PW2a of the first auxiliary electrode 212 are greater than the length PL1b and width PW1b of the second antenna electrode 114 (see Figure 2C).

[0026] The first opposing electrode 222 and the second opposing electrode 224 are respectively superimposed on the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A. The first opposing electrode 222 includes a first through hole 222h superimposed on the first auxiliary electrode 212, and the second opposing electrode 224 includes a second through hole 224h superimposed on the second auxiliary electrode 214. The first through hole 222h and the second through hole 224h are respectively superimposed on the first opening 122h and the second opening 124h.

[0027] The first opposing electrode 222 is connected to the second opposing electrode 224. In some embodiments, in order to improve the transmittance of the first metasurface structure 200A for visible light, the first opposing electrode 222, the second opposing electrode 224, or both are designed with a slit to allow more visible light to pass through.

[0028] In some embodiments, the first auxiliary electrode 212, the second auxiliary electrode 214, the first opposing electrode 222, and the second opposing electrode 224 in the first metasurface structure 200A are not directly connected to an external power source. That is, voltage is not directly supplied to the first auxiliary electrode 212, the second auxiliary electrode 214, the first opposing electrode 222, and the second opposing electrode 224. In some embodiments, the first auxiliary electrode 212, the second auxiliary electrode 214, the first opposing electrode 222, and the second opposing electrode 224 are floating electrodes (or floatingly grounded). In some embodiments, the first metasurface structure 200A does not contain active elements.

[0029] In some embodiments, the shape of the first through-hole 222h is equal to the shape of the second through-hole 224h. In this embodiment, both the first through-hole 222h and the second through-hole 224h are cross-shaped, which can correspond to horizontal polarization signals and vertical polarization signals. In other embodiments, the first through-hole 222h and the second through-hole 224h have other shapes. For example, in this embodiment, the four endpoints of the cross shape are arc-shaped, but the invention is not limited thereto. In other embodiments, the four endpoints of the cross shape are rectangular, trapezoidal, or other symmetrical shapes. When the four endpoints of the cross shape are trapezoidal, its shape resembles two bow ties overlapping each other perpendicularly.

[0030] In some embodiments, the size of the first through-hole 222h is equal to the size of the second through-hole 224h. For example, the width SL2a of the first through-hole 222h and the width SL2b of the second through-hole 224h are 1000 micrometers to 1600 micrometers, such as 1300 micrometers. For example, the first through-hole 222h and the second through-hole 224h each include four extensions extending outward from the center, and the width SW2a of the extension of the first through-hole 222h and the width SW2b of the extension of the second through-hole 224h are 200 micrometers to 600 micrometers, such as 400 micrometers.

[0031] The first dielectric layer 230 is located between the first auxiliary electrode 212 and the first counter electrode 222, and between the second auxiliary electrode 214 and the second counter electrode 224. In some embodiments, the material of the first dielectric layer 230 includes liquid crystal polymer (LCP), polyimide (PI), modified polyimide (MPI), an air layer, or a combination thereof, or other dielectric layers. In this embodiment, unlike the liquid crystal layer 130 whose dielectric constant changes with the electric field between the antenna electrode and the common electrode, the dielectric constant of the first dielectric layer 230 is a fixed value. In FIG. 2A, the first dielectric layer 230 is not filled in the first via 222h, the second via 224h, or between the first auxiliary electrode 212 and the second auxiliary electrode 214, but this disclosure is not limited thereto. In other embodiments, the first dielectric layer 230 is filled in the first via 222h, the second via 224h, and between the first auxiliary electrode 212 and the second auxiliary electrode 214.

[0032] In some embodiments, the first metasurface structure 200A is formed directly on the first side 102 of the liquid crystal antenna device 100A. For example, a first opposing electrode 222 and a second opposing electrode 224 are first formed. Then, a first dielectric layer 230 is formed on the first opposing electrode 222 and the second opposing electrode 224. Finally, a first auxiliary electrode 212 and a second auxiliary electrode 214 are formed on the first dielectric layer 230 on the second substrate 150. In other embodiments, the first metasurface structure 200A is attached to the first side 102 of the liquid crystal antenna device 100A by an adhesive layer (not shown).

[0033] Please refer to Figures 2A and 2D. The second metasurface structure 300A includes a third auxiliary electrode 312, a fourth auxiliary electrode 314, a third opposing electrode 322, a fourth opposing electrode 324, and a second dielectric layer 330.

[0034] The third auxiliary electrode 312 and the fourth auxiliary electrode 314 are respectively superimposed on the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A. In this embodiment, the third auxiliary electrode 312 and the fourth auxiliary electrode 314 are respectively superimposed on the first antenna electrode 112 and the second antenna electrode 114.

[0035] In some embodiments, the shape of the third auxiliary electrode 312 is equal to the shape of the fourth auxiliary electrode 314. In some embodiments, the third auxiliary electrode 312 and the fourth auxiliary electrode 314 each have a symmetrical shape, such as a square, a circle, a hexagon, etc.

[0036] In this embodiment, the size of the third auxiliary electrode 312 is not equal to the size of the fourth auxiliary electrode 314. In other words, the length PL3a and width PW3a of the third auxiliary electrode 312 are the same as or different from the length PL3b and width PW3b of the fourth auxiliary electrode 314. In this embodiment, the length PL3a is equal to the width PW3a and is in the range of 500 micrometers to 1100 micrometers, for example, 835 micrometers; the length PL3b is equal to the width PW3b and is in the range of 600 micrometers to 1200 micrometers, for example, 870 micrometers. In this embodiment, the length PL3a and width PW3a of the third auxiliary electrode 312 are equal to the length PL2a and width PW2a of the first auxiliary electrode 212 that overlaps with it (see FIG. 2C), and the length PL3b and width PW3b of the fourth auxiliary electrode 314 are equal to the length PL2b and width PW2b of the second auxiliary electrode 214 that overlaps with it (see FIG. 2C).

[0037] The third opposing electrode 322 and the fourth opposing electrode 324 are respectively superimposed in the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A. The third opposing electrode 322 includes a third through hole 322h superimposed on the third auxiliary electrode 312, and the fourth opposing electrode 324 includes a fourth through hole 324h superimposed on the fourth auxiliary electrode 314. The third through hole 322h and the fourth through hole 324h are respectively superimposed on the first opening 122h and the second opening 124h.

[0038] The third opposing electrode 322 is connected to the fourth opposing electrode 324. In some embodiments, in order to improve the transmittance of the second metasurface structure 300A for visible light, the third opposing electrode 322, the fourth opposing electrode 324, or both are designed with a slit to allow more visible light to pass through.

[0039] In some embodiments, the third auxiliary electrode 312, the fourth auxiliary electrode 314, the third opposing electrode 322, and the fourth opposing electrode 324 in the second metasurface structure 300A are not directly connected to an external power source. That is, voltage is not directly supplied to the third auxiliary electrode 312, the fourth auxiliary electrode 314, the third opposing electrode 322, and the fourth opposing electrode 324. In some embodiments, the third auxiliary electrode 312, the fourth auxiliary electrode 314, the third opposing electrode 322, and the fourth opposing electrode 324 are floating electrodes (or floatingly grounded). In some embodiments, the second metasurface structure 300A does not contain active elements.

[0040] In some embodiments, the shape of the third through-hole 322h is equal to the shape of the fourth through-hole 324h. In this embodiment, both the third through-hole 322h and the fourth through-hole 324h are cross-shaped, which can correspond to horizontal polarization signals and vertical polarization signals. In other embodiments, the third through-hole 322h and the fourth through-hole 324h have other shapes. For example, in this embodiment, the four endpoints of the cross shape are arc-shaped, but the invention is not limited thereto. In other embodiments, the four endpoints of the cross shape are rectangular, trapezoidal, or other symmetrical shapes. When the four endpoints of the cross shape are trapezoidal, its shape resembles two bow ties overlapping each other perpendicularly.

[0041] In some embodiments, the size of the third through-hole 322h is equal to the size of the fourth through-hole 324h. For example, the width SL3a of the third through-hole 322h and the width SL3b of the fourth through-hole 324h are 1000 micrometers to 2000 micrometers, such as 1300 micrometers. For example, the third through-hole 322h and the fourth through-hole 324h each include four extensions extending outward from the center, and the width SW3a of the extension of the third through-hole 322h and the width SW3b of the extension of the fourth through-hole 324h are 200 micrometers to 800 micrometers, such as 400 micrometers. In some embodiments, the first through-hole 222h, the second through-hole 224h, the third through-hole 322h, and the fourth through-hole 324h have the same shape and size. In some embodiments, the size of the first through-hole 222h, the second through-hole 224h, the third through-hole 322h, and the fourth through-hole 324h is larger than the size of the first opening 122h and the second opening 124h.

[0042] The second dielectric layer 330 is located between the third auxiliary electrode 312 and the third counter electrode 322, and between the fourth auxiliary electrode 314 and the fourth counter electrode 324. In some embodiments, the material of the second dielectric layer 330 includes liquid crystal polymer, polyimide, modified polyimide, an air layer, or a combination thereof, or other dielectric layers. In this embodiment, unlike the liquid crystal layer 130, whose dielectric constant changes in response to the electric field between the antenna electrode and the common electrode, the dielectric constant of the second dielectric layer 330 is a fixed value. In some embodiments, the first dielectric layer 230 and the second dielectric layer 330 comprise the same or different materials. In some embodiments, the thickness of the first dielectric layer 230 is the same as or different from the thickness of the second dielectric layer 330. In FIG. 2A, the second dielectric layer 330 is not filled in the third via 322h, the fourth via 324h, or between the third auxiliary electrode 312 and the fourth auxiliary electrode 314, but this disclosure is not limited thereto. In other embodiments, the second dielectric layer 330 is filled in the third via 322h, the fourth via 324h, and between the third auxiliary electrode 312 and the fourth auxiliary electrode 314.

[0043] In some embodiments, the second metasurface structure 300A is formed directly on the second side 104 of the liquid crystal antenna device 100A. For example, a third opposing electrode 322 and a fourth opposing electrode 324 are first formed on the first substrate 140. Then, a second dielectric layer 330 is formed on the third opposing electrode 322 and the fourth opposing electrode 324. Finally, a third auxiliary electrode 312 and a fourth auxiliary electrode 314 are formed on the second dielectric layer 330. In other embodiments, the second metasurface structure 300A is attached to the second side 104 of the liquid crystal antenna device 100A by an adhesive layer (not shown).

[0044] In some embodiments, the materials of the first antenna electrode 112, the second antenna electrode 114, the first common electrode 122, the second common electrode 124, the first auxiliary electrode 212, the second auxiliary electrode 214, the first opposing electrode 222, the second opposing electrode 224, the third auxiliary electrode 312, the fourth auxiliary electrode 314, the third opposing electrode 322, and the fourth opposing electrode 324 include metals, alloys, conductive oxides, conductive polymers, or combinations thereof, or other suitable conductive materials.

[0045] Figures 3A to 3D are schematic diagrams of the first to fourth operating modes of the electromagnetic wave modulation device of Figure 2A. In this embodiment, the first metasurface structure 200A and the second metasurface structure 300A provide a 180-degree phase shift to the electromagnetic wave signal at the position overlapping the first liquid crystal control area X1, and provide a 0-degree phase shift (or no phase shift) to the electromagnetic wave signal at the position overlapping the second liquid crystal control area X2. On the other hand, the first liquid crystal control area X1 and the second liquid crystal control area X2 of the liquid crystal antenna device 100A each have an on mode and an off mode. In the off mode, the electromagnetic wave signal cannot pass through the liquid crystal control area, while in the on mode, a 90-degree or 0-degree phase shift can be provided to the electromagnetic wave signal by controlling the liquid crystal layer in the liquid crystal control area. It should be noted that in the embodiments of Figures 3A to 3D, the phase shift angle is only for illustration and not for limiting the present invention; the actual phase shift angle can be adjusted as needed.

[0046] Please refer to Figure 3A. In the first operating mode, the first liquid crystal control area X1 of the liquid crystal antenna device 100A is switched to the off mode, and the second liquid crystal control area X2 is switched to the on mode, so that the electromagnetic wave signal MS emitted by the base station 30 can pass through the second liquid crystal control area X2 but cannot pass through the first liquid crystal control area X1.

[0047] In this embodiment, the first metasurface structure 200A and the second metasurface structure 300A provide a 0-degree phase shift to the electromagnetic wave signal at the position overlapping the second liquid crystal control area X2, and the second liquid crystal control area X2 of the liquid crystal antenna device 100A also provides a 0-degree phase shift in the first operating mode. Therefore, the electromagnetic wave signal emitted by the base station 30 exhibits a 0-degree phase shift (or no phase shift) after passing through the electromagnetic wave modulation device 10A in the first operating mode.

[0048] Please refer to Figures 2A and 3A. In some embodiments, in the first operating mode, the voltage difference between the first antenna electrode 112 and the first common electrode 122 is 0 volts, while the voltage difference between the second antenna electrode 114 and the second common electrode 124 is V1.

[0049] Figure 3B shows the second operating mode of the liquid crystal antenna device 100A. Unlike the first operating mode, in the second operating mode, the second liquid crystal control area X2 of the liquid crystal antenna device 100A provides a 90-degree phase shift, so the electromagnetic wave signal transmitted by the base station 30 experiences a 90-degree phase shift after passing through the electromagnetic wave modulation device 10A in the second operating mode.

[0050] Referring to Figures 2A and 3B, in some embodiments, in the second operating mode, the voltage difference between the first antenna electrode 112 and the first common electrode 122 is 0 volts, while there is a voltage difference V2 between the second antenna electrode 114 and the second common electrode 124. The voltage difference V2 is not equal to the voltage difference V1.

[0051] Please refer to Figure 3C. In the third operating mode, the second liquid crystal control area X2 of the liquid crystal antenna device 100A is switched to the off mode, and the first liquid crystal control area X1 is switched to the on mode, so that the electromagnetic wave signal emitted by the base station 30 can pass through the first liquid crystal control area X1 but cannot pass through the second liquid crystal control area X2.

[0052] In this embodiment, the first metasurface structure 200A and the second metasurface structure 300A provide a 180-degree phase shift to the electromagnetic wave signal at the position overlapping the first liquid crystal control area X1, and the first liquid crystal control area X1 of the liquid crystal antenna device 100A provides a 0-degree phase shift in the third operating mode. Therefore, the electromagnetic wave signal emitted by the base station 30 exhibits a 180-degree phase shift after passing through the electromagnetic wave modulation device 10A in the third operating mode.

[0053] Please refer to Figures 2A and 3C. In some embodiments, in the third operating mode, there is a voltage difference V3 between the first antenna electrode 112 and the first common electrode 122, while the voltage difference between the second antenna electrode 114 and the second common electrode 124 is 0 volts.

[0054] Figure 3D shows the fourth operating mode of the liquid crystal antenna device 100A. Unlike the third operating mode, in the fourth operating mode, the first liquid crystal control area X1 of the liquid crystal antenna device 100A provides a 90-degree phase shift, so the electromagnetic wave signal transmitted by the base station 30 experiences a 270-degree phase shift after passing through the electromagnetic wave modulation device 10A in the fourth operating mode.

[0055] Referring to Figures 2A and 3D, in some embodiments, in the fourth operating mode, there is a voltage difference V4 between the first antenna electrode 112 and the first common electrode 122, while the voltage difference between the second antenna electrode 114 and the second common electrode 124 is 0 volts. The voltage difference V4 is different from the voltage difference V3.

[0056] In some embodiments, voltage difference V1 is equal to voltage difference V3, and voltage difference V2 is equal to voltage difference V4. In some embodiments, voltage difference V1 is not equal to voltage difference V3, and voltage difference V2 is not equal to voltage difference V4.

[0057] Figure 4A is an amplitude diagram of the S21 parameter of an electromagnetic wave modulation device according to an embodiment of the present invention under different first to fourth operating modes. Figure 4B is a diagram of the phase in degree of the S21 parameter of an electromagnetic wave modulation device according to an embodiment of the present invention under different first to fourth operating modes. The first to fourth operating modes of the electromagnetic wave modulation device in Figures 4A and 4B can be referred to the embodiments in Figures 3A to 3D, the only difference being the phase shift angle.

[0058] Referring to Figure 4A, in this embodiment, for electromagnetic waves with a frequency of 28 GHz, the relative permittivity of the liquid crystal layer in the liquid crystal control region is 3.61 in the first and third operating modes, and 3.01 in the second and fourth operating modes. Furthermore, for electromagnetic waves with a frequency of 28 GHz, the amplitudes of parameter S21 in the first to fourth operating modes are -5 dB, -7 dB, -5 dB, and -4 dB, respectively. Ideally, the amplitude of parameter S21 in all four operating modes is 0 dB.

[0059] Referring to Figure 4B, in this embodiment, for electromagnetic waves with a frequency of 28 GHz, the electromagnetic wave modulation device provides phase shifts (or phase modulation values) of 0 degrees, 52 degrees, 183 degrees, and 229 degrees in the first to fourth operating modes, respectively. Ideally, the electromagnetic wave modulation device provides phase shifts of 0 degrees, 90 degrees, 183 degrees, and 270 degrees in the first to fourth operating modes, respectively.

[0060] Figure 5 is a schematic diagram of an electromagnetic wave modulation device according to an embodiment of the present invention. It should be noted that the embodiment in Figure 5 uses the component reference numerals and some content from the embodiments in Figures 2A to 2D, wherein the same or similar reference numerals are used to represent the same or similar components, and descriptions of the same technical content are omitted. For explanations of the omitted parts, please refer to the foregoing embodiments, which will not be repeated here.

[0061] Please refer to Figure 5. In this embodiment, the electromagnetic wave signal emitted by the base station 30 is modulated using an electromagnetic wave modulation device 10A. For example, after the modulated electromagnetic wave passes through the electromagnetic wave modulation device 10A, the direction of the main lobe M is at an angle θ (e.g., 30 degrees) with the normal direction of the electromagnetic wave modulation device 10A, while the radiation intensity of the side lobe S is less than about -13.2 dB.

[0062] FIG6 is an exploded view of an electromagnetic wave modulation device according to an embodiment of the present invention. It should be noted that the embodiment of FIG6 uses the component reference numerals and some contents of the embodiments of FIG2A to FIG2D, wherein the same or similar reference numerals are used to represent the same or similar components, and the description of the same technical content is omitted. For the description of the omitted parts, please refer to the foregoing embodiments, which will not be repeated here.

[0063] Please refer to FIG6. In this embodiment, the electromagnetic wave modulation device 10B includes a liquid crystal antenna device 100A, a first metasurface structure 200B disposed on a first side 102 of the liquid crystal antenna device 100A, and a second metasurface structure 300B disposed on a second side 104 of the liquid crystal antenna device 100A. The contents of the liquid crystal antenna device 100A are described in the preceding descriptions of FIG2A and 2C, and will not be repeated here.

[0064] In this embodiment, the first dielectric layer 230 in the first metasurface structure 200B is an air layer with a fixed dielectric constant.

[0065] In this embodiment, the first metasurface structure 200B further includes a first substrate 240 and a second substrate 250, wherein the first auxiliary electrode 212, the second auxiliary electrode 214, the first counter electrode 222, the second counter electrode 224 and the first dielectric layer 230 are located between the first substrate 240 and the second substrate 250.

[0066] In some embodiments, the first substrate 240 is attached to the liquid crystal antenna device 100A via an adhesive layer (not shown), but the present invention is not limited thereto. In other embodiments, the first substrate 240 may be omitted, and the first opposing electrode 222 and the second opposing electrode 224 are formed directly on the second substrate 150 of the liquid crystal antenna device 100A.

[0067] In this embodiment, the second dielectric layer 330 in the second metasurface structure 300B is an air layer with a fixed dielectric constant.

[0068] In this embodiment, the second metasurface structure 300B further includes a first substrate 340 and a second substrate 350, wherein the third auxiliary electrode 312, the fourth auxiliary electrode 314, the third counter electrode 322, the fourth counter electrode 324 and the second dielectric layer 330 are located between the first substrate 340 and the second substrate 350.

[0069] In some embodiments, the second substrate 340 is attached to the liquid crystal antenna device 100A via an adhesive layer (not shown), but the present invention is not limited thereto. In other embodiments, the second substrate 340 may be omitted, and the third opposing electrode 322 and the fourth opposing electrode 324 are formed directly on the first substrate 140 of the liquid crystal antenna device 100A.

[0070] In summary, in this embodiment, by incorporating the metasurface structure into the liquid crystal antenna device, the phase modulation of the electromagnetic wave modulation device can be improved. [Simplified Explanation of the Diagram]

[0071] Figure 1 is a schematic diagram of an electromagnetic wave modulation device according to an embodiment of the present invention. Figure 2A is an exploded view of an electromagnetic wave modulation device according to an embodiment of the present invention. Figure 2B is a top view of a first metasurface structure according to an embodiment of the present invention. Figure 2C is a top perspective view of a liquid crystal antenna device structure according to an embodiment of the present invention. Figure 2D is a top view of a second metasurface structure according to an embodiment of the present invention. Figures 3A to 3D are schematic diagrams of the first to fourth operating modes of the electromagnetic wave modulation device of Figure 2A, respectively. Figure 4A is a graph of the magnitude of the S21 parameter of an electromagnetic wave modulation device according to an embodiment of the present invention under different first to fourth operating modes. Figure 4B is a graph of the phase in degree of the S21 parameter of an electromagnetic wave modulation device according to an embodiment of the present invention under different first to fourth operating modes. Figure 5 is a schematic diagram of an electromagnetic wave modulation device according to an embodiment of the present invention. Figure 6 is an exploded view of an electromagnetic wave modulation device according to an embodiment of the present invention.

Claims

1. An electromagnetic wave modulation device, comprising: A liquid crystal antenna device includes: a first antenna electrode and a second antenna electrode, respectively located in a first liquid crystal control region and a second liquid crystal control region of the liquid crystal antenna device; a first common electrode and a second common electrode, respectively located in the first liquid crystal control region and the second liquid crystal control region of the liquid crystal antenna device, wherein the first common electrode includes a first opening overlapping the first antenna electrode, and the second common electrode includes a second opening overlapping the second antenna electrode; a liquid crystal layer located between the first antenna electrode and the first common electrode and between the second antenna electrode and the second common electrode; and a first metasurface structure disposed on a first side of the liquid crystal antenna device, and including: a first auxiliary electrode and a second auxiliary electrode, respectively overlapping the first liquid crystal control region and the second liquid crystal control region of the liquid crystal antenna device; A first opposing electrode and a second opposing electrode, wherein the first opposing electrode includes a first through-hole overlapping the first auxiliary electrode, and the second opposing electrode includes a second through-hole overlapping the second auxiliary electrode; and a first dielectric layer located between the first auxiliary electrode and the first opposing electrode and between the second auxiliary electrode and the second opposing electrode, wherein the dielectric constant of the first dielectric layer is a fixed value.

2. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the first common electrode is electrically connected to the second common electrode, and the size and shape of the first opening are equal to the size and shape of the second opening.

3. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the size of the first antenna electrode is not equal to the size of the second antenna electrode.

4. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the first opposing electrode is connected to the second opposing electrode, and the size and shape of the first through hole are equal to the size and shape of the second through hole.

5. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the size of the first auxiliary electrode is not equal to the size of the second auxiliary electrode.

6. The electromagnetic wave modulation apparatus of claim 1, wherein the size of the first auxiliary electrode is smaller than the size of the second auxiliary electrode, and the size of the first antenna electrode is smaller than the size of the second antenna electrode.

7. The electromagnetic wave modulation apparatus as described in claim 1, further comprising: A second metasurface structure is disposed on the second side of the liquid crystal antenna device, wherein the liquid crystal antenna device is located between the first metasurface structure and the second metasurface structure, and the second metasurface structure includes: a third auxiliary electrode and a fourth auxiliary electrode, respectively overlapping the first liquid crystal control region and the second liquid crystal control region of the liquid crystal antenna device; a third opposing electrode and a fourth opposing electrode, wherein the third opposing electrode includes a third through-hole overlapping the third auxiliary electrode, and the fourth opposing electrode includes a fourth through-hole overlapping the fourth auxiliary electrode; and a second dielectric layer is located between the third auxiliary electrode and the third opposing electrode and between the fourth auxiliary electrode and the fourth opposing electrode, wherein the dielectric constant of the second dielectric layer is a fixed value.

8. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the liquid crystal antenna apparatus comprises: First substrate; An active element layer is located on the first substrate and includes a first active element electrically connected to the first antenna electrode and a second active element electrically connected to the second antenna electrode; and a second substrate, wherein the liquid crystal layer is located between the first substrate and the second substrate.

9. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the material of the first dielectric layer comprises a liquid crystal polymer, polyamide, modified polyamide, an air layer, or a combination thereof.

10. The electromagnetic wave modulation apparatus as claimed in claim 1, wherein the first auxiliary electrode and the second auxiliary electrode are floating electrodes.

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