Liquid crystal phase shifter and liquid crystal antenna

Abstract

The application discloses a liquid crystal phase shifter and a liquid crystal antenna, and relates to the technical field of antennas, and specifically relates to a liquid crystal phase shifter and a liquid crystal antenna. The application discloses a liquid crystal phase shifter and a liquid crystal antenna, and relates to the technical field of antennas, and specifically relates to a liquid crystal phase shifter and a liquid crystal antenna. The first orientation layer and the second orientation layer are provided with a set pre-tilt angle, and are used for pre-orienting the liquid crystal layer; when the liquid crystal ECB mode is adopted, the pre-tilt angle of the first orientation layer and the second orientation layer is set to be 2-5 degrees; when the liquid crystal VA mode is adopted, the pre-tilt angle of the first orientation layer and the second orientation layer is set to be 80-89 degrees. The liquid crystal phase shifter and the liquid crystal antenna provided by the application prevent the anti-tilt phenomenon of the liquid crystal material in the liquid crystal phase shifter by setting the orientation layer with the pre-tilt angle, and improve the phase modulation accuracy of the liquid crystal phase shifter on the electromagnetic wave signal.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology, specifically relating to a liquid crystal phase shifter and a liquid crystal antenna. Background Technology

[0002] With the gradual evolution of communication systems, phase shifters have been used more and more widely. Liquid crystal antennas are a new type of arrayed antenna based on liquid crystal phase shifters. They are devices that convert electrical signals and radio frequency signals and are now widely used in satellite receiving antennas, mobile vehicle transceiver antennas, base station antennas and other fields.

[0003] The liquid crystal phase shifter is the core component of a liquid crystal antenna, used to adjust the phase of electromagnetic waves. However, in existing liquid crystal phase shifter designs, the liquid crystal material is prone to anti-tilt phenomena. Due to intermolecular forces, the anti-tilt region affects the alignment of nearby liquid crystals, causing the liquid crystal alignment to become disordered and unable to operate according to the predetermined dielectric constant, thus affecting the modulation accuracy of the liquid crystal phase shifter on the electromagnetic wave phase. Summary of the Invention

[0004] This invention provides a liquid crystal phase shifter and a liquid crystal antenna to solve the problem that the liquid crystal material in existing liquid crystal phase shifters and liquid crystal antennas is prone to reverse tilting, resulting in low phase modulation accuracy.

[0005] To solve the above-mentioned technical problems, the present invention provides a liquid crystal phase shifter, comprising an upper substrate, a first electrode layer, a first alignment layer, a liquid crystal layer, a second alignment layer, a second electrode layer, and a lower substrate stacked together;

[0006] Both the first alignment layer and the second alignment layer have a set pretilt angle for pre-aligning the liquid crystal layer;

[0007] When using the liquid crystal ECB mode, the pretilt angle of the first alignment layer and the second alignment layer is set to 2-5°; when using the liquid crystal VA mode, the pretilt angle of the first alignment layer and the second alignment layer is set to 80-89°.

[0008] As a further improvement of the present invention, the thickness of both the first orientation layer and the second orientation layer is 20-500 nm.

[0009] As a further improvement of the present invention, the first orientation layer and the second orientation layer are provided with the same pretilt angle.

[0010] As a further improvement of the present invention, the opposite sides of the liquid crystal layer are in contact with the first alignment layer and the second alignment layer, respectively.

[0011] As a further improvement of the present invention, the liquid crystal phase shifter further includes a bezel adhesive, which is disposed around the liquid crystal layer, and the liquid crystal layer is encapsulated between the first alignment layer and the second alignment layer by the bezel adhesive.

[0012] As a further improvement of the present invention, a plurality of spacers are provided in the frame adhesive, and the spacers are used to adjust the thickness of the liquid crystal layer.

[0013] As a further improvement of the present invention, the first electrode layer and the second electrode layer form an electric field at both ends of the liquid crystal layer to regulate the torsion angle of the liquid crystal molecules in the liquid crystal layer.

[0014] As a further improvement of the present invention, the second electrode layer includes a bias electrode for connecting to a peripheral drive to control the electric field strength between the first electrode layer and the second electrode layer.

[0015] As a further improvement of the present invention, the first electrode layer includes a ground electrode layer; the second electrode layer further includes a transmission electrode, wherein the ground electrode layer covers the area where the transmission electrode is located in the vertical projection of the lower substrate.

[0016] The present invention also provides a liquid crystal antenna, which includes the liquid crystal phase shifter described above.

[0017] Compared with the prior art, the liquid crystal phase shifter and liquid crystal antenna provided by the present invention use inorganic materials as the alignment layer, which effectively improves the light stability and the weather resistance of the liquid crystal antenna. At the same time, the alignment layer with a pretilt angle of 2-5° or 85-89° is set, which effectively prevents the anti-tilt phenomenon of liquid crystal material in the liquid crystal phase shifter and improves the phase modulation accuracy of electromagnetic waves. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a liquid crystal phase shifter provided in an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of a liquid crystal phase shifter in which the pretilt angle is set by a vapor deposition method, according to an embodiment of the present invention.

[0021] Figure 3This is a schematic diagram of an array of liquid crystal phase shifters and liquid crystal antennas provided in an embodiment of the present invention.

[0022] Explanation of reference numerals in the attached figures

[0023] 10-Upper substrate; 101-Radiation electrode; 102-Radiation coupling gap; 20-First electrode layer; 30-First alignment layer; 40-Liquid crystal layer; 41-Frame adhesive; 50-Second alignment layer; 60-Second electrode layer; 601-Feed electrode; 602-Transmission electrode; 603-Bias electrode; 604-Bias electrode interface; 605-Feed coupling gap; 70-Lower substrate; 80-Feed unit; 90-Radiation unit. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] To make the description of this disclosure more detailed and complete, illustrative descriptions of embodiments and specific examples of the present invention are provided below; however, these are not the only forms of implementing or utilizing the specific examples of the present invention. The embodiments cover features of multiple specific examples and methods and steps for constructing and operating these specific examples, and their order. However, other specific examples may also be used to achieve the same or equivalent functions and order of steps.

[0026] To address the problem of low phase modulation accuracy caused by the reverse tilting of liquid crystal materials in existing liquid crystal phase shifters and liquid crystal antennas, this embodiment provides a liquid crystal phase shifter. Please refer to... Figure 1 The liquid crystal phase shifter includes an upper substrate 10 and a lower substrate 70 disposed opposite to each other, and a liquid crystal layer 40 located between the upper substrate 10 and the lower substrate 70.

[0027] Furthermore, a first electrode layer 20 and a first alignment layer 30 are sequentially disposed on the side of the upper substrate 10 facing the liquid crystal layer 40, and a second electrode layer 60 and a second alignment layer 60 are sequentially disposed on the side of the lower substrate 70 facing the liquid crystal layer 40, and the upper and lower sides of the liquid crystal layer 40 are in contact with the first alignment layer 30 and the second alignment layer 60, respectively.

[0028] In this embodiment, the upper substrate 10 and the lower substrate 70 are made of materials with good stability and insulation effect and low dielectric loss, such as quartz glass or high boron content glass. The dielectric loss value is preferably less than 0.005@10GHz. It should be noted that since high dielectric loss materials have a large dielectric loss value, the dielectric loss is also greater, resulting in a worse transmission efficiency of electromagnetic wave signals. In this embodiment, the upper substrate 10 and the lower substrate 70 are made of low dielectric loss materials. The lower the loss, the better the electromagnetic wave transmission performance. This can effectively reduce the non-radiative loss of electromagnetic wave signals caused by passing through the substrate and liquid crystal layer 40, and further improve the final transmission power of the electromagnetic wave signal.

[0029] Furthermore, a frame adhesive 41 is provided between the upper substrate 10 and the lower substrate 70. The frame adhesive 41 is disposed around the sides of the liquid crystal layer 40, encapsulating the liquid crystal layer 40 between the first alignment layer 30 and the second alignment layer 50. The upper and lower sides of the liquid crystal layer 40 are in contact with the first alignment layer 30 and the second alignment layer 50, respectively, thereby forming the liquid crystal device. At the same time, a number of spacers (not shown in the figure) are also provided in the frame adhesive 41. The spacers are used to adjust the overall thickness of the liquid crystal layer 40 and the liquid crystal device.

[0030] In this embodiment, the liquid crystal layer 40 is prepared using liquid crystal material and its Δε is set to be greater than 0.5 (@10GHz), where Δε = |ε∥-ε⊥|; Δε represents the absolute value of the difference in dielectric constant between the liquid crystal material in the two states of being parallel to the substrate and perpendicular to the substrate, ε∥ represents the dielectric constant of the liquid crystal material when it is parallel to the substrate, and ε⊥ represents the dielectric constant of the liquid crystal material when it is perpendicular to the substrate.

[0031] Since the liquid crystal molecules in the liquid crystal layer 40 are anisotropic materials with different dielectric constants, their dielectric constants can be changed by changing the twist angle of the liquid crystal molecules. When the twist directions of the liquid crystal molecules in the liquid crystal layer 40 are different, the electromagnetic wave signals passing through the liquid crystal layer 40 will have different dielectric constants, which will cause the phase of the electromagnetic wave signals to change after passing through the liquid crystal layer 40, thereby achieving the effect of phase modulation.

[0032] Furthermore, a first alignment layer 30 is disposed between the liquid crystal layer 40 and the first electrode layer 20, and a second alignment layer 50 is disposed between the liquid crystal layer 40 and the second electrode layer 60. The first alignment layer 30 and the second alignment layer 50 are used to limit the initial deflection angle of the liquid crystal molecules in the liquid crystal layer 40. After alignment, the liquid crystal molecules will be arranged in a direction parallel to or perpendicular to the substrate. Specifically, the thickness of the first alignment layer 30 and the second alignment layer 50 is preferably set in the range of 20-500 nm.

[0033] In this embodiment, a first electrode layer 20 is disposed at the bottom of the upper substrate 10, and a second electrode layer 60 is disposed at the top of the lower substrate 70. The first electrode layer 20 and the second electrode layer 60 are used to apply an electric field to the liquid crystal molecules in the liquid crystal layer 40. Specifically, the first electrode layer 20 is a ground electrode layer. The second electrode layer 60 includes a feed electrode 601, a transmission electrode 602 connected to the feed electrode 601, a bias electrode 603, and a bias electrode interface 604 used in conjunction with the bias electrode 603. The feed electrode 601 is electrically connected to the transmission electrode 602. The feed electrode 601 is used to receive external electromagnetic wave signals, the transmission electrode 602 is used to transmit electromagnetic wave signals, and the bias electrode interface 604 is used to connect to the external driving voltage.

[0034] The transmission electrode 602 can be made of a high-conductivity metal, but is not limited to metal materials. It can be set as a composite conductive layer such as indium tin oxide (ITO), conductive silver nanowires, conductive gold nanowires, graphene, or molybdenum / aluminum / molybdenum, with a thickness greater than 0.5 μm and a sheet resistance of Ω1. To ensure that the electromagnetic wave signal loss at the transmission electrode 602 is sufficiently low, the resistance Ω1 of the transmission electrode 602 must be sufficiently low. Therefore, the transmission electrode 602 needs to have a certain electrode thickness. Most high-conductivity metals have a charge accumulation thickness of about 0.5 μm at a certain frequency, so the thickness of the transmission electrode 602 should be at least greater than 0.5 μm, which can greatly reduce the loss of electromagnetic wave signal during transmission. Of course, in other embodiments, the material and thickness of the transmission electrode 602 can be adjusted according to the actual situation, and are not limited here.

[0035] The bias electrode 603 can be made of a low-conductivity metal or oxide. The bias electrode interface 604 is connected to an external driving voltage to control the electric field strength between the first electrode layer 20 and the second electrode layer 60, thereby changing the torsion angle of the liquid crystal molecules in the liquid crystal layer 40. Its electrode thickness is <0.2um and its sheet resistance is Ω2.

[0036] It should be noted that the aforementioned transmission electrode 602 and bias electrode 603 should satisfy σ h >σ l Ω2 / Ω1>100; This setting is to ensure that the electromagnetic wave signal is transmitted on the transmission electrode 602 as much as possible and does not fall on the bias electrode 603, so as to prevent the electromagnetic signal from causing more loss at the bias electrode 603. Therefore, the transmission electrode 602 needs to have a higher conductivity and a lower resistance, and the bias electrode 603 needs to have a lower conductivity and a higher resistance. This can effectively reduce the loss of electromagnetic wave signal during transmission, so that the liquid crystal phase shifter has lower power consumption and a higher signal-to-noise ratio.

[0037] Furthermore, the ground electrode layer is made of the same material as the transmission electrode 602, which is also made of a high-conductivity metal; at the same time, the vertical projection of the ground electrode layer on the lower substrate 70 should cover the area where the transmission electrode 602 is located, that is, the area where the transmission electrode 602 is located should be included by the vertical projection of the ground electrode layer.

[0038] Furthermore, the transmission electrode 602 and the bias electrode 603 should be disposed on the same plane. The bias electrode interface 604 is used to connect the external driving voltage. When a low-frequency AC current of less than 1kHz is applied to the bias electrode 603, since the electromagnetic wave operating frequency is above 1GHz, the applied low-frequency AC current and the transmitted electromagnetic wave signal do not interfere with each other. At this time, there is a voltage difference between the first electrode layer 20 and the second electrode layer 60, which will form an electric field at both ends of the liquid crystal layer 40. The electric field drives the liquid crystal molecules in the liquid crystal layer 40 to change the torsion angle, which is equivalent to changing the equivalent dielectric constant of the liquid crystal layer 40. The phase of the electromagnetic wave signal changes after passing through the liquid crystal layer 40, thereby achieving the effect of modulating the phase of the electromagnetic wave signal. It should be noted that when no electric field is applied between the first electrode layer 20 and the second electrode layer 60, the liquid crystal molecules in the liquid crystal layer 40 are arranged parallel or perpendicularly along a preset direction under the action of the first alignment layer 30 and the second alignment layer 50.

[0039] Specifically, the phase modulation principle here can be expressed by the formula... Explanation: The left side of the equation For phase, f on the right side of the equation is the electromagnetic wave frequency, ε r Let ε be the dielectric constant of the medium, L be the electrical length of the liquid crystal phase shifter, and c be the speed of light. r The dielectric constant of the liquid crystal material can be connected to the external driving voltage through the bias electrode 603. By changing the electric field strength between the first electrode layer 20 and the second electrode layer 60, the deflection angle of the liquid crystal molecules in the liquid crystal layer 40 can be controlled, thereby modulating the phase of the electromagnetic wave signal during the phase shift process.

[0040] In this embodiment, the feed electrode 601 is used to feed in external electromagnetic wave signals. It can be made of high conductivity materials such as Au, Cu, Ag, etc., and its electrode thickness is >0.5um. The external electromagnetic wave signals are transmitted to the feed electrode 601 through a standard connector SMA. A feed coupling gap 605 is also provided between the feed electrode 601 and the transmission electrode 602. The electromagnetic wave signals are fed into the transmission electrode 602 after passing through the feed coupling gap 605. The feed coupling gap 605 is equivalent to a specific capacitor. Under high frequency conditions, the impedance of the capacitor is small and the coupling loss is also small.

[0041] To prevent the liquid crystal molecules in the liquid crystal layer 40 from exhibiting reverse tilting, which could affect the alignment of nearby liquid crystal molecules and cause disordered arrangement of the liquid crystal material within the liquid crystal layer 40, thus preventing the liquid crystal device from operating according to the predetermined dielectric constant, the first alignment layer 30 and the second alignment layer 50 provided in this embodiment of the invention are both provided with the same pretilt angle. Furthermore, the liquid crystal molecules in the liquid crystal layer 40 will align in a specific direction under the action of the first alignment layer 30 and the second alignment layer 50. Software fitting shows that this specific direction is determined by the pretilt angle direction of the alignment layer. At the same time, the liquid crystal molecules after alignment by the first alignment layer 30 and the second alignment layer 50 will align in a direction parallel to or perpendicular to the substrate.

[0042] Specifically, when using the liquid crystal ECB mode, i.e., the liquid crystal flat mode, in order to align the liquid crystal molecules after alignment along the parallel direction of the substrate, the pretilt angle of the first alignment layer 30 and the second alignment layer 50 should be set in the range of 2 to 5°; when using the VA mode, i.e., the liquid crystal vertical mode, in order to align the liquid crystal molecules after alignment along the vertical direction of the substrate, the pretilt angle of the first alignment layer 30 and the second alignment layer 50 should be set in the range of 80 to 89°.

[0043] Software fitting results show that for the liquid crystal ECB mode, when the pretilt angle is set to 0° and the applied voltage is applied, there is a 50% probability of anti-tilt phenomenon. Therefore, the larger the pretilt angle, the less likely anti-tilt will occur. Thus, the pretilt angle of the first alignment layer 30 and the second alignment layer 50 should be set in the range of 2 to 5°. Similarly, for the liquid crystal VA mode, when the pretilt angle is set to 90° and the applied voltage is applied, there is a 50% probability of anti-tilt phenomenon. Therefore, the smaller the pretilt angle, the less likely anti-tilt will occur. Thus, the pretilt angle of the first alignment layer 30 and the second alignment layer 50 should be set in the range of 80 to 89°.

[0044] It should be noted that the 2-5° and 80-89° provided in this embodiment of the invention are the optimal pretilt angle selection ranges obtained after multiple fitting operations, and are not intended to limit the pretilt angle to be adjusted only within this range. Those skilled in the art can adjust the pretilt angle of the first orientation layer 30 and the second orientation layer 50 according to their needs, and no further restrictions are imposed here.

[0045] In one specific embodiment of this example, the first alignment layer 30 and the second alignment layer 50 can be made using the PI friction process in the prior art, specifically made of polyimide material, abbreviated as PI material. During alignment, the first alignment layer 30 and the second alignment layer 50 are rubbed together, and the polyimide material moves in one direction, so that the liquid crystal molecules in the liquid crystal layer 40 are arranged according to the direction of the preset top. The above-mentioned PI friction process steps are known to those skilled in the art, so they will not be described in detail here.

[0046] Please refer to Figure 2 In one specific embodiment of this example, in order to improve the light stability of the liquid crystal device and the weather resistance of the liquid crystal antenna, the first alignment layer 30 and the second alignment layer 50 can be aligned by tilting the deposition of inorganic oxide SiO2. Specifically, SiO2 material is deposited in a high vacuum of less than 5×10e-3Pa, and the deposition rate is controlled at 0.5nm / s. The substrate is tilted above the deposition source, and the angle between the normal of the plane on which the substrate is located and the line connecting the center of the substrate and the deposition source is β. The pretilt angle of the first alignment layer 30 and the second alignment layer 50 is determined by this β.

[0047] In another specific embodiment of this example, the first alignment layer 30 and the second alignment layer 50 can also be aligned by UV light irradiation. A photoalignment material, such as a polymer containing azo groups, a polymer containing cinnamic yl groups, or a polyimide material, is uniformly coated on a substrate on which an electrode layer has been laid. Then, the substrate is pre-cured to evaporate the solvent and form a solid film. Finally, the substrate with the alignment material is irradiated with UV light to form the final alignment layer.

[0048] Furthermore, a radiation electrode 101 is provided on the side of the upper substrate 10 away from the liquid crystal layer 40. The radiation electrode 101 is used in conjunction with the feed electrode 601. The feed electrode 601 is used to feed in electromagnetic wave signals, and the radiation electrode 101 is used to radiate outward electromagnetic wave signals after the phase is modulated by the liquid crystal device.

[0049] A radiation coupling gap 102 is also provided between the transmission electrode 602 and the radiation electrode 101. The radiation coupling gap 102 is equivalent to a specific capacitor. In the case of high frequency, the impedance of the specific capacitor is small and the coupling loss is also small. The electromagnetic wave signal after phase modulation is transmitted to the radiation electrode 101 through the radiation coupling gap 102, and then radiated outward by the radiation electrode 101.

[0050] The working principle of this liquid crystal phase shifter is as follows: An electromagnetic wave signal is fed into the feed electrode 601 in the feed unit 80. The electromagnetic wave signal is transmitted to the liquid crystal layer 40 via the transmission electrode 602. Under the action of the bias electrode 603, an electric field is formed between the first electrode layer 20 and the second electrode layer 60. The deflection direction of the liquid crystal molecules in the liquid crystal layer 40 changes, causing a change in their equivalent dielectric constant. The phase of the electromagnetic wave signal changes after passing through the liquid crystal layer 40, thus achieving phase modulation. After phase modulation ends, the electromagnetic wave signal is radiated outward through the radiation electrode 101 in the radiation unit 90. It should be further noted that the feed unit 80 specifically includes the feed electrode 601 and the feed coupling gap 605, and the radiation unit 90 specifically includes the radiation electrode 101 and the radiation coupling gap 102.

[0051] Please continue to refer to Figure 3This embodiment also provides a liquid crystal antenna. Figure 3 This is a schematic diagram of a liquid crystal antenna consisting of 2×2 of the above-mentioned liquid crystal phase shifter arrays; of course, the antenna structure provided in this embodiment can also be composed of M×N of the above-mentioned liquid crystal phase shifter arrays, where M and N are both natural numbers greater than or equal to 2; the arrows in the figure indicate the direction of electromagnetic wave signal transmission.

[0052] The liquid crystal antenna includes a feed system, a phase shifter system, a bias system, and a radiation system. The feed system is composed of an array of feed electrodes 601 in the liquid crystal phase shifter, used to feed electromagnetic wave signals into the phase shifter system. The phase shifter system is composed of an array of transmission electrodes 602 and liquid crystal layers 40 in the liquid crystal phase shifter, and the electromagnetic wave signals are transmitted to the liquid crystal layers 40 in each liquid crystal phase shifter via the transmission electrodes 602. The bias system is composed of an array of bias electrodes 603 in the liquid crystal phase shifter. Under the action of the bias electrodes 603, the equivalent dielectric constant of the liquid crystal layer 40 changes, causing the phase of the electromagnetic wave signals to change after passing through the liquid crystal layer 40. The radiation system is composed of an array of radiation electrodes 101 in the liquid crystal phase shifter, and the electromagnetic wave signals after phase modulation are radiated outward through the radiation system.

[0053] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A liquid crystal phase shifter, characterized in that, It includes an upper substrate, a first electrode layer, a first alignment layer, a liquid crystal layer, a second alignment layer, a second electrode layer, and a lower substrate, which are stacked together. Both the first alignment layer and the second alignment layer are provided with the same pretilt angle for pre-aligning the liquid crystal layer; When using the liquid crystal ECB mode, the pretilt angle of the first alignment layer and the second alignment layer is set to 2~5°; when using the liquid crystal VA mode, the pretilt angle of the first alignment layer and the second alignment layer is set to 80~89°; and, The second electrode layer includes a feed electrode and a transmission electrode connected to the feed electrode. A feed coupling gap is provided between the feed electrode and the transmission electrode. A radiation electrode is provided on the side of the upper substrate away from the liquid crystal layer. A radiation coupling gap is provided between the transmission electrode and the radiation electrode.

2. A liquid crystal phase shifter as described in claim 1, characterized in that, The thickness of both the first alignment layer and the second alignment layer is 20-500 nm.

3. A liquid crystal phase shifter as described in claim 1, characterized in that, The liquid crystal layer is in contact with the first alignment layer and the second alignment layer on opposite sides, respectively.

4. A liquid crystal phase shifter as described in claim 1, characterized in that, The liquid crystal phase shifter also includes a bezel adhesive, which is disposed around the liquid crystal layer, and the liquid crystal layer is encapsulated between the first alignment layer and the second alignment layer by the bezel adhesive.

5. A liquid crystal phase shifter as described in claim 4, characterized in that, The frame adhesive has a plurality of spacers inside, which are used to adjust the thickness of the liquid crystal layer.

6. A liquid crystal phase shifter as described in claim 1, characterized in that, The first electrode layer and the second electrode layer form an electric field at both ends of the liquid crystal layer, which is used to control the twist angle of the liquid crystal molecules in the liquid crystal layer.

7. A liquid crystal phase shifter as described in claim 6, characterized in that, The second electrode layer includes a bias electrode for controlling the electric field strength between the first electrode layer and the second electrode layer.

8. A liquid crystal phase shifter as described in claim 7, characterized in that, The first electrode layer includes a ground electrode layer, the ground electrode layer covering the area where the transmission electrode is located in the vertical projection of the lower substrate.

9. A liquid crystal antenna, characterized in that, The liquid crystal antenna includes a liquid crystal phase shifter as described in any one of claims 1-8.

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