Electromagnetic wave modulation structure

Abstract

An electromagnetic wave modulation structure includes a liquid crystal cell. The liquid crystal box comprises a plurality of modulation units. Each modulation unit comprises a first conductive pattern, a second conductive pattern and a liquid crystal layer. The first conductive pattern is configured on the first surface of the first substrate, wherein the first conductive pattern comprises a plurality of phase shift sheets which are separated and arranged along a direction, and a serial connection wire for connecting the phase shift sheets in series. The second conductive pattern is disposed on the second surface of the second substrate, wherein the first surface faces the second surface. The second conductive pattern includes dipoles corresponding to the phase shift sheets. The liquid crystal layer is disposed between the first conductive pattern and the second conductive pattern. The serial leads of the modulation units are electrically connected with a common lead.

Description

Technical Field

[0001] This invention relates to a communication device, and more particularly to an electromagnetic wave modulation structure. Background Technology

[0002] In recent years, reconfigurable intelligent surfaces (RIS) have been used to address the signal dead zone problem caused by the poor diffraction of high-frequency signals due to their ability to flexibly manipulate electromagnetic waves. The dielectric properties of the liquid crystal molecules within a RIS can be controlled by changing the voltage. RIS with variable capacitance plays an important role in communication systems.

[0003] In certain environments, frequent switching of liquid crystal molecule orientation is not required, so high-frequency liquid crystals with bistable properties can be selected. However, these liquid crystal molecules require a relatively high driving voltage. If the driving voltage is too low, the liquid crystal molecules may not be driven accurately, affecting communication quality. Summary of the Invention

[0004] This invention provides an electromagnetic wave modulation structure that offers excellent communication quality.

[0005] According to an embodiment of the present invention, an electromagnetic wave modulation structure is provided, including a liquid crystal cell. The liquid crystal cell includes a first substrate, a second substrate, and a plurality of modulation units sandwiched between the first substrate and the second substrate. Each modulation unit includes a first conductive pattern, a second conductive pattern, and a liquid crystal layer. The first conductive pattern is disposed on a first surface of the first substrate, wherein the first conductive pattern includes a plurality of discrete phase shifters arranged along a direction, and series wires connecting the phase shifters. The second conductive pattern is disposed on a second surface of the second substrate, wherein the first surface faces the second surface. The second conductive pattern includes dipoles corresponding to the phase shifters. The liquid crystal layer is disposed between the first conductive pattern and the second conductive pattern. The series wires of the modulation units are electrically connected to a common wire.

[0006] Based on the above, the electromagnetic wave modulation structure provided in this embodiment of the invention utilizes dipoles and phase shifters to drive the liquid crystal layer. Multiple phase shifters are connected in series with connecting wires, and these connecting wires are electrically connected to a common wire. Accordingly, the transistor can drive the liquid crystal layer with a higher driving voltage, and the electromagnetic wave modulation structure can provide good communication quality.

[0007] To make the above features and advantages of the present invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0008] Figure 1 A schematic diagram of an electromagnetic wave modulation structure according to some embodiments of the present invention is shown.

[0009] Figure 2 An exploded view of a liquid crystal cell according to some embodiments of the present invention is shown.

[0010] Figure 3A A partial top view of a liquid crystal cell according to an embodiment of the present invention is shown. Figure 3B Show along Figure 3A A schematic diagram of the cross-section of line AA'. Figure 3C Show along Figure 3A A schematic diagram of the cross-section of line B'B. Figure 3D Show Figure 3A A plan view of some of the structures in the diagram. Figure 3E Show Figure 3A A planar schematic diagram of some of the structures.

[0011] Figure 4 A partial top view of a liquid crystal cell according to an embodiment of the present invention is shown.

[0012] Figure 5 A schematic diagram of the driving voltage according to some embodiments of the present invention is shown.

[0013] Explanation of reference numerals in the attached figures: 1: Electromagnetic wave modulation structure 10: LCD box 20: Reflective sheet 100: Modulation Unit 101: First conductive pattern 101A: Photo Shifter 101B: Impedance matching element 101C: Series wire 102: Second conductive pattern 102A: Dipole component 102B: Dipole component 102D: Dipole A1: Face A2: Face C1: Curve C2: Curve EB: Electromagnetic waves I1: Insulating layer I2: Insulating layer LC: Liquid Crystal Layer L1: Data cable L11: Part 1 L12: Part Two L2: Data cable L21: Part 1 L22: Part Two L com Common conductor S1: First substrate S2: Second substrate T1: Transistor T2: Transistor V c Common voltage Detailed Implementation

[0014] Reference Figure 1 , Figure 2 , Figure 3A , Figure 3B , Figure 3C , Figure 3D , Figure 3E as well as Figure 4 ,in Figure 1 A schematic diagram of an electromagnetic wave modulation structure according to some embodiments of the present invention is shown. Figure 2 An exploded view of a liquid crystal cell according to some embodiments of the present invention is shown. Figure 3A A partial top view of a liquid crystal cell according to an embodiment of the present invention is shown. Figure 3B Show along Figure 3A A schematic diagram of the cross-section of line AA'. Figure 3C Show along Figure 3A A schematic diagram of the cross-section of line B'B. Figure 3D Show Figure 3A A plan view of some of the structures in the diagram. Figure 3E Show Figure 3A A plan view of some of the structures in the diagram. Figure 4 A partial top view of a liquid crystal cell according to an embodiment of the present invention is shown.

[0015] In one embodiment of the present invention, the electromagnetic wave modulation structure 1 includes a liquid crystal cell 10 and a reflective sheet 20, wherein the liquid crystal cell 10 is disposed between the reflective sheet 20 and the incident side of the electromagnetic wave EB. The liquid crystal cell 10 includes a first substrate S1, a second substrate S2, and a plurality of modulation units 100 sandwiched between the first substrate S1 and the second substrate S2. Each modulation unit 100 includes a first conductive pattern 101, a second conductive pattern 102, and a liquid crystal layer LC.

[0016] like Figure 2 As shown. The first conductive pattern 101 of each modulation unit 100 is disposed on surface A1 of the first substrate S1. The second conductive pattern 102 of each modulation unit 100 is disposed on surface A2 of the second substrate S2, wherein surface A2 faces surface A1. The liquid crystal layer LC is located between the first conductive pattern 101 and the second conductive pattern 102. An insulating layer I1 is disposed between the liquid crystal layer LC and the first conductive pattern 101, and an insulating layer I2 is disposed between the liquid crystal layer LC and the second conductive pattern 102.

[0017] Simultaneously refer to Figure 2, Figure 3A , Figure 3C as well as Figure 3D The first conductive pattern 101 includes a plurality of discrete phase shifters 101A, a plurality of impedance matching elements 101B, and a series conductor 101C arranged along the Y direction. The series conductor 101C connects the phase shifters 101A in series. (See also...) Figure 2 , Figure 3A , Figure 3B as well as Figure 3E The second conductive pattern 102 includes dipole components 102A and 102B, wherein dipole components 102A and 102B constitute a dipole 102D, and dipole components 102A and 102B are electrically connected to transistors T1 and T2 through data lines L1 and L2, respectively.

[0018] like Figure 3A As shown, the dipole 102D on surface A2 corresponds to the phase shifters 101A and impedance matching elements 101B on surface A1, wherein data lines L1 and L2 are electrically connected to the portions of the dipole members 102A and 102B corresponding to the phase shifters 101A, respectively. Accordingly, the liquid crystal layer LC located between the first conductive pattern 101 and the second conductive pattern 102 can be driven by transistors T1 and T2.

[0019] It should be noted that you should also refer to Figure 2 , Figure 3A , Figure 3D as well as Figure 4 The series wires 101C that connect the phase shifters 101A in series within the modulation units 100 are all electrically connected to a common wire L of the liquid crystal cell 10. com And the common conductor L com Connect a common voltage V c In a comparative example (not shown), the phase shifters 101A within the modulation unit 100 are configured with a floating ground, making it difficult for transistors T1 and T2 to provide a large drive voltage. In contrast, in the electromagnetic wave modulation structure 1 provided by this invention, the phase shifters 101A are connected to a common voltage V. c Common voltage V c This can be the ground voltage. In this configuration, transistors T1 and T2 can drive the liquid crystal layer LC with a higher driving voltage. In some embodiments, the liquid crystal layer LC includes a bistable high-frequency liquid crystal (e.g., cholesteric liquid crystal). With the above configuration, transistors T1 and T2 can provide sufficient driving voltage to drive the high-frequency liquid crystal.

[0020] In some embodiments, when the liquid crystal layer LC of the electromagnetic wave modulation structure 1 requires a higher driving voltage, it can utilize... Figure 5 The common modulation architecture shown is used to configure the common voltage V. c (as shown in curve C1) and the drive voltage transmitted by data lines L1 and L2 (as shown in curve C2) to reduce the load on transistors T1 and T2.

[0021] Reference Figure 3A as well as Figure 3D In a preferred embodiment, the resistance per unit length of the series conductor 101C is greater than that of the common conductor L. com Resistance per unit length. A series conductor 101C with higher impedance can prevent coupling losses in high-frequency signals. A common conductor L with lower impedance... com This avoids RC delay and ensures driving performance. In some embodiments, the series conductor 101C may include indium tin oxide, and the common conductor L... com It can include, but is not limited to, metallic copper.

[0022] It should also be noted that the series conductor 101C is not connected in series with the impedance matching elements 101B to avoid excessive resistance due to excessive length of the series conductor 101C, which could lead to uneven driving. However, the present invention is not limited thereto. In some embodiments, the series conductor 101C is connected in series with the phase shifters 101A and the impedance matching elements 101B.

[0023] Reference Figure 3A as well as Figure 3E In a preferred embodiment, data line L1 includes a first portion L11 near dipole member 102A and a second portion L12 away from dipole member 102A, wherein the resistance of the first portion L11 per unit length is greater than the resistance of the second portion L12 per unit length. Similarly, data line L2 includes a first portion L21 near dipole member 102B and a second portion L22 away from dipole member 102B, wherein the resistance of the first portion L21 per unit length is greater than the resistance of the second portion L22 per unit length. Because the first portion L11 near dipole member 102A and the first portion L21 near dipole member 102B have higher impedance, coupling loss of high-frequency signals can be avoided. In some embodiments, the first portion L11 and the first portion L21 may comprise indium tin oxide, and the second portion L12 and the second portion L22 may comprise metallic copper, but are not limited thereto.

[0024] In summary, the electromagnetic wave modulation structure provided in this embodiment of the invention utilizes dipoles, phase shifters, and impedance matching elements to drive the liquid crystal layer. Multiple phase shifters are connected in series with a series wire, and the series wire is electrically connected to a common wire. Accordingly, the transistor can drive the liquid crystal layer with a higher driving voltage, and the electromagnetic wave modulation structure can provide good communication quality.

Claims

1. An electromagnetic wave modulation structure, comprising a liquid crystal cell, the liquid crystal cell comprising a first substrate, a second substrate, and a plurality of modulation units sandwiched between the first substrate and the second substrate, each modulation unit comprising: A first conductive pattern is disposed on a first surface of the first substrate, wherein the first conductive pattern includes a plurality of discrete phase shifters arranged along one direction, and a series wire connecting the plurality of phase shifters in series. A second conductive pattern is disposed on a second surface of the second substrate, wherein the second surface faces the first surface, and the second conductive pattern includes a dipole corresponding to the plurality of phase shifters; as well as A liquid crystal layer is disposed between the first conductive pattern and the second conductive pattern. The multiple series wires of the multiple modulation units are electrically connected to a common wire.

2. The electromagnetic wave modulation structure as described in claim 1, wherein the resistance of the series conductor per unit length is greater than the resistance of the common conductor per unit length.

3. The electromagnetic wave modulation structure according to any one of claims 1 or 2, wherein the series conductor comprises indium tin oxide.

4. The electromagnetic wave modulation structure as claimed in claim 1, wherein the dipole comprises two dipole members, each dipole member being electrically connected to a data line, the data line comprising a first portion close to the dipole member and a second portion away from the dipole member, wherein the resistance of the first portion per unit length is greater than the resistance of the second portion per unit length.

5. The electromagnetic wave modulation structure of claim 4, wherein the first portion of the data line comprises indium tin oxide.

6. The electromagnetic wave modulation structure as claimed in claim 4, wherein the common conductor is connected to a common voltage, and the common voltage and a driving voltage transmitted by the data line are configured using a common electrode voltage modulation architecture.

7. The electromagnetic wave modulation structure of claim 1, wherein the first conductive pattern further comprises a plurality of discrete impedance matching elements arranged along the direction, the plurality of impedance matching elements being arranged corresponding to the dipole.

8. The electromagnetic wave modulation structure of claim 7, wherein the dipole comprises two dipole components, each dipole component comprising a first portion corresponding to the plurality of phase shifters and a second portion corresponding to the plurality of impedance matching elements, and a data line electrically connecting the first portion of each dipole component.

9. The electromagnetic wave modulation structure as described in claim 7, wherein the series conductor is not connected in series with the plurality of impedance matching elements.

10. The electromagnetic wave modulation structure of claim 1, wherein the liquid crystal layer comprises a high-frequency liquid crystal having a bistable state.

11. The electromagnetic wave modulation structure of claim 10, wherein the liquid crystal layer comprises cholesterol liquid crystal.

12. The electromagnetic wave modulation structure of claim 1 further includes a reflector, wherein the liquid crystal cell is disposed between the reflector and the electromagnetic wave incident side.

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