Phase shifting unit, phase shifter array and phased array antenna

Abstract

The invention discloses a phase shifting unit, a phase shifter array and a phased-array antenna, and belongs to the technical field of antennas. The second substrate is arranged opposite to the first substrate; the liquid crystal layer is arranged between the first substrate and the second substrate; the signal transmission structure is arranged on the side, close to the liquid crystal layer, of the first substrate and / or the second substrate and comprises at least one signal line and a cantilever branch knot connected to the side, close to the liquid crystal layer, of the signal line; wherein the orthographic projection of the signal line on the first substrate is overlapped with the orthographic projection of the liquid crystal layer on the first substrate, the size of the cantilever branch knot is micron-scale or nano-scale, and the cantilever branch knot is configured to vibrate in the thickness direction of the liquid crystal layer under the driving of an electric signal.

Description

Phase shifter unit, phase shifter array, and phased array antenna Technical Field

[0001] The present disclosure relates to the field of antenna technology, and in particular to a phase shift unit, a phase shifter array, and a phased array antenna. Background Art

[0002] Phase shifters are generally classified into two types: digital and analog. Digital phase shifters typically utilize microwave switches to direct microwaves along different paths, with the lengths of these paths optimally designed to achieve phase control. Analog phase shifters, on the other hand, utilize materials with adjustable dielectric constants or magnetic permeabilities. By applying an external voltage or magnetic field to alter the material properties, the wavelength of the dielectric medium can be altered, thereby achieving phase control.

[0003] Among them, the liquid crystal phase shifter achieves continuous phase adjustment by changing the dielectric constant of liquid crystal.

[0004] Overview

[0005] The present disclosure provides a phase shift unit, comprising:

[0006] a first substrate;

[0007] a second substrate, disposed opposite to the first substrate;

[0008] a liquid crystal layer disposed between the first substrate and the second substrate; and

[0009] a signal transmission structure, disposed on a side of the first substrate and / or the second substrate close to the liquid crystal layer, comprising at least one signal line and a cantilever branch connected to the signal line on a side close to the liquid crystal layer;

[0010] The orthographic projection of the signal line on the first substrate overlaps with the orthographic projection of the liquid crystal layer on the first substrate, and the size of the cantilever branch is in the micrometer or nanometer order, and is configured to vibrate in the thickness direction of the liquid crystal layer under the drive of an electrical signal.

[0011] Exemplarily, the orthographic projection of the cantilever branch on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate;

[0012] The signal transmission structure is constructed with a capacitor structure, two electrodes of the capacitor structure are arranged opposite to each other in the thickness direction of the liquid crystal layer, and at least one of the electrodes is the cantilever branch.

[0013] Exemplarily, the signal transmission structure is located on the first substrate, and the phase shifting unit further includes:

[0014] a flat panel layer located on a side of the second substrate close to the liquid crystal layer, wherein an orthographic projection of the flat panel layer on the second substrate overlaps an orthographic projection of the cantilever branch on the second substrate;

[0015] Wherein, one electrode of the capacitor structure is the cantilever branch, and the other electrode is the flat layer.

[0016] Exemplarily, the flat plate layer includes:

[0017] a metal floor layer having a slotted area, wherein an orthographic projection of the slotted area on the second substrate does not overlap with an orthographic projection of the cantilever branch on the second substrate and covers an orthographic projection of the microstrip line on the second substrate;

[0018] A metal isolation layer is located on a side of the metal floor layer close to the liquid crystal layer, and an orthographic projection of the metal isolation layer on the second substrate at least covers an orthographic projection of the cantilever branch on the second substrate.

[0019] Exemplarily, the signal transmission structure includes two symmetrically arranged signal lines, a microstrip gap is provided between the two signal lines, and the cantilever branches are distributed within the microstrip gap or outside the microstrip gap.

[0020] Exemplarily, the cantilever branches are distributed in the microstrip gap; wherein the cantilever branches to which the two signal lines are respectively connected are arranged at intervals in the extension direction of the signal line.

[0021] Exemplarily, the microstrip gap has a first size in a target direction, and the signal line has a second size in the target direction;

[0022] The first size and the second size are both smaller than λ / 100, λ is the wavelength of the center frequency, and the target direction is a direction orthogonal to the extension direction of the signal line.

[0023] Exemplarily, the target region in the liquid crystal layer, located between the cantilever branch and the flat layer, has a target size in the thickness direction of the liquid crystal layer;

[0024] The ratio of the first size to the target size is greater than 0.005, and the ratio of the second size to the target size is less than 5.

[0025] Exemplarily, the signal transmission structure is located on the first substrate or the second substrate, and the signal line includes a first signal line, a second signal line, and a third signal line connected between the first signal line and the second signal line;

[0026] Two ends of the cantilever branch are connected to the first signal line and the second signal line respectively, and there is a gap between the cantilever branch and the third signal line in the thickness direction of the liquid crystal layer, and the liquid crystal layer includes a liquid crystal region located in the gap;

[0027] Wherein, one electrode of the capacitor structure is the cantilever branch, and the other electrode is the third signal line.

[0028] Exemplarily, the signal lines include a fourth signal line located on a side of the first substrate close to the liquid crystal layer, and a fifth signal line located on a side of the second substrate close to the liquid crystal layer;

[0029] The cantilever branches include a first cantilever branch connected to the fourth signal line, and a second cantilever branch connected to the fifth signal line;

[0030] The orthographic projection of the first cantilever branch on the first substrate overlaps with the orthographic projection of the second cantilever branch on the first substrate, so that the first cantilever branch and the second cantilever branch constitute the capacitor structure.

[0031] Exemplarily, the orthographic projection of the cantilever branch on the first substrate does not overlap with the orthographic projection of the liquid crystal layer on the first substrate, and the cantilever branch is stacked on a side of the signal line close to the liquid crystal layer and is parallel to the signal line.

[0032] Exemplarily, the signal line includes two symmetrically arranged signal lines, and the cantilever branches connected to the two signal lines are symmetrically structured relative to the signal lines.

[0033] Exemplarily, the phase shifting unit further includes:

[0034] a reverse stress layer formed on a side of a target substrate close to the liquid crystal layer; wherein the target substrate includes at least one of the first substrate and the second substrate on which the signal transmission structure is formed;

[0035] Wherein, the signal transmission structure is located on a side of the reverse stress layer close to the liquid crystal layer.

[0036] Exemplarily, an orthographic projection of the cantilever branch on the first substrate is located within an orthographic projection of the liquid crystal layer on the first substrate and is orthogonal to the signal line, and the cantilever branch has a third dimension in a target direction and a fourth dimension in a direction orthogonal to the target direction;

[0037] The third dimension and the fourth dimension are both smaller than λ / 10, λ is the wavelength of the center frequency, and the target direction is a direction orthogonal to the extension direction of the signal line.

[0038] Exemplarily, a dimension of the signal line in the extension direction is greater than λ / 2, where λ is the wavelength of the center frequency.

[0039] Another phase shifter array in the present disclosure includes any of the multiple phase shifting units described above; wherein the multiple phase shifting units are arranged in an array, and the signal transmission structures of the multiple phase shifting units located in the same row or column share the same signal line.

[0040] Exemplarily, the orthographic projection of the cantilever branch in the phase shift unit on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate, and the signal transmission structure is constructed with a capacitor structure;

[0041] The cantilever branches in different phase shifting units have different sizes, including a third size in a target direction and / or a fourth size in a direction orthogonal to the target direction, where the target direction is a direction orthogonal to the extension direction of the signal line.

[0042] Exemplarily, the orthographic projection of the cantilever branch in the phase shift unit on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate, and the signal transmission structure is constructed with a capacitor structure;

[0043] Among the multiple phase shifting units sharing the same signal line, the spacing between the cantilever branches in every two adjacent phase shifting units is less than λ / 10; wherein λ is the wavelength corresponding to the center frequency.

[0044] Exemplarily, the distances between the cantilever branches in every two adjacent phase-shifting units are the same.

[0045] Another phased array antenna disclosed in the present invention comprises a plurality of antenna array elements and any one of the plurality of phase shifting units corresponding to each of the antenna elements.

[0046] The phase shifter provided by the present disclosure includes a first substrate, a second substrate, and a liquid crystal layer located between the first and second substrates, and also includes a signal transmission structure located on the side of the first substrate and / or the second substrate close to the liquid crystal layer. The signal transmission structure may include at least one signal line and a cantilever branch connected to the side of the signal line close to the liquid crystal layer. The orthographic projection of the signal line on the first substrate overlaps with the orthographic projection of the liquid crystal layer on the first substrate. The cantilever branch has a size on the order of micrometers or nanometers and is configured to vibrate in the thickness direction of the liquid crystal layer under the drive of an electrical signal. Because the cantilever branch is on the order of micrometers or nanometers, the cantilever branch can respond quickly under the drive of the electrical signal, for example, it can respond in microseconds, thereby greatly improving the response time of the liquid crystal phase shifter. As a result, the phase shifter can combine the advantages of the liquid crystal phase shifter and the microsecond fast adjustment of the microelectromechanical system, so that the antenna system composed of the phase shifter has high beam pointing accuracy and overall efficiency.

[0047] The above description is only an overview of the technical solution of the present disclosure. In order to more clearly understand the technical means of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present disclosure more obvious and easy to understand, the specific implementation methods of the present disclosure are listed below.

[0048] BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or related technologies, the following is a brief introduction to the drawings required for the description of the embodiments or related technologies. Obviously, the drawings described below are some embodiments of the present disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without inventive efforts. It should be noted that the scales in the drawings are for illustration only and do not represent the actual scale.

[0050] FIG1 shows a schematic top plan view of a phase shift unit;

[0051] FIG2 shows a schematic diagram of the BB cross-sectional structure of the phase shift unit shown in FIG1 ;

[0052] FIG3 shows a schematic cross-sectional structure diagram of a phase shift unit in Example 1;

[0053] FIG4 shows a schematic cross-sectional structure diagram of a phase shift unit in Example 2;

[0054] FIG5 shows a schematic cross-sectional structure diagram of a phase shift unit in Example 3;

[0055] FIG6 shows a schematic top view of the structure of a phase shift unit of Example 1;

[0056] FIG7 is a schematic top plan view of the metal floor layer in the phase shift unit shown in FIG6 ;

[0057] FIG8 shows a schematic diagram of the AA cross-sectional structure of the phase shift unit shown in FIG7 ;

[0058] 9a and 9b are schematic top plan views of two further phase shifting units of Example 1;

[0059] FIG10 shows a schematic cross-sectional structure diagram of a phase shift unit in Example 2;

[0060] FIG11 is a schematic diagram showing a top plan structure of a phase shifting unit in Example 3;

[0061] FIG12 is a schematic diagram showing a cross-sectional structure of the phase shift unit in FIG11 in a direction;

[0062] FIG13 is a schematic top plan view of yet another phase shifting unit of Example 3;

[0063] FIG14 shows a schematic top plan view of a phase shifting unit in yet another example;

[0064] FIG15 shows a schematic cross-sectional structure diagram of a phase shift unit A;

[0065] FIG16 is a schematic top view of the metal floor layer in the phase shift unit A;

[0066] FIG17 shows a schematic cross-sectional structure diagram of a phase shift unit B;

[0067] FIG18 shows a pattern layer of the metal floor layer in the phase shift unit B;

[0068] FIG19a and FIG19b respectively show schematic top views of two phase shifter arrays;

[0069] FIG20 shows an equivalent circuit diagram of a phase shifter array;

[0070] FIG21 shows a variation of the phase shifter array shown in FIG19a;

[0071] FIG22 shows a schematic top plan view of yet another phase shifter array.

[0072] Detailed description

[0073] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure more clear, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present disclosure, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present disclosure without making any creative efforts shall fall within the scope of protection of the present disclosure.

[0074] In related technologies, since the adjustable range of the dielectric constant of liquid crystal is relatively small, a larger physical size is required to achieve a 360° phase difference. However, this design leads to problems such as long response time and insufficient phase shifting of the liquid crystal phase shifter, which in turn leads to low beam switching efficiency of the antenna system composed of this phase shifter and difficulty in achieving multi-beam scanning.

[0075] In view of this, the inventors have improved the signal transmission structure of the liquid crystal phase shifter to solve the problems of response time and phase shift amount of the liquid crystal phase shifter. By coupling micro-electromechanical branches to traditional signal lines, a new liquid crystal phase shifter with the advantages of both can be prepared. Specifically, it can utilize the adjustable characteristics and fast response speed of the micro-electromechanical branches to greatly improve the phase shift amount of the liquid crystal phase shifter, thereby improving the beam switching response speed and reducing the beam switching time.

[0076] 1 and 2 , FIG1 shows a schematic top plan view of a phase shift unit, and FIG2 shows a schematic BB cross-sectional structure diagram of the phase shift unit shown in FIG1 . As shown in FIG1 and FIG2 , the phase shift unit 100 of the present disclosure may include:

[0077] a first substrate 11;

[0078] The second substrate 12 is arranged opposite to the first substrate 11;

[0079] a liquid crystal layer 2 disposed between the first substrate and the second substrate; and

[0080] The signal transmission structure 3 is provided on the side of the first substrate and / or the second substrate close to the liquid crystal layer, and includes at least one signal line 31 and a cantilever branch 32 connected to the side of the signal line 31 close to the liquid crystal layer 2;

[0081] The orthographic projection of the signal line on the first substrate overlaps with the orthographic projection of the liquid crystal layer on the first substrate. The size of the cantilever branch is in the micrometer or nanometer order and is configured to vibrate in the thickness direction of the liquid crystal layer under the drive of the electrical signal.

[0082] In this embodiment, the materials of the first substrate and the second substrate can be the same or different. The materials can be commonly used PCB (Printed Circuit Board) insulating materials such as polytetrafluoroethylene glass fiber laminates, phenolic paper laminates, phenolic glass cloth laminates, etc., or can be hard materials with low microwave loss such as quartz and glass. The thicknesses of the first substrate and the second substrate can be the same or different. Specifically, the thicknesses of the first substrate and the second substrate are both 100 microns to 10 mm.

[0083] Liquid crystal can be filled between the first substrate and the second substrate to form a liquid crystal layer. It should be noted that a plurality of spacer columns can be provided between the first substrate and the second substrate. The plurality of spacer columns can be used to support a certain filling space for the liquid crystal layer, thereby facilitating the filling of liquid crystal in the filling space to form a liquid crystal layer. The thickness of the liquid crystal layer is 1 to 100 μm, specifically 5 to 15 μm. The preparation process of 5 to 15 μm is relatively mature. Compared with a liquid crystal layer of >40 μm, it can effectively reduce the liquid crystal response time, thereby improving the device response speed. In this example, the thickness of the liquid crystal layer can be less than 1 / 1000 of the operating wavelength of the center frequency.

[0084] In this embodiment, a signal transmission structure is also included. The signal transmission structure can be arranged on the side of the first substrate close to the liquid crystal layer, or on the side of the second substrate close to the liquid crystal layer. Alternatively, the signal transmission structure may include a partial structure arranged on the side of the first substrate close to the liquid crystal layer, and a partial structure arranged on the side of the second substrate close to the liquid crystal layer. The specific arrangement can be based on actual needs.

[0085] Among them, the signal transmission structure is mainly used to transmit signals, which may include at least one signal line and a cantilever branch connected to the signal line. The cantilever branch can be connected to the side of the signal line close to the liquid crystal layer, so that the cantilever branch can be set closer to the liquid crystal. Specifically, the signal line and the cantilever branch can be made of metal materials. The two can use the same metal material or different metal materials. For example, the signal line can use a metal material with low resistance characteristics such as copper, gold, and silver, and the material of the cantilever branch can be Mo-Al-Mo alloy. In addition to the alloy, it can also be a metal material with low resistance characteristics such as copper, gold, and silver, or a low-loss metal or other alloy. Among them, the signal line and the cantilever branch can be prepared by magnetron sputtering, thermal evaporation, electroplating and other methods.

[0086] The signal transmission structure may include one signal line or multiple signal lines. As shown in FIG1 and FIG2 , a case where one signal line is included is shown. In the case where one signal line is included, the signal transmission structure may be provided on the first substrate or the second substrate. In the case where multiple signal lines are included, the multiple signal lines may all be located on the first substrate or the second substrate, or the multiple signal lines may be distributed on the first substrate and the second substrate. In the case where the multiple signal lines are distributed on the first substrate and the second substrate, the signal transmission structure may be configured as a differential signal transmission structure, thereby forming a signal transmission structure on both the first substrate and the second substrate.

[0087] In the case of including multiple signal lines, each signal line may be connected to a cantilever stub; alternatively, some signal lines may be connected to cantilever stubs while others may not be connected to cantilever stubs. In this case, the signal lines connected to the cantilever stubs may be located on the same substrate, or the signal lines connected to the cantilever stubs may be located on different substrates. For example, if the signal transmission structure is configured as a differential signal transmission structure, the signal lines connected to the cantilever stubs may be distributed on different substrates.

[0088] Among them, for each signal line, the orthographic projection of the signal line on the first substrate overlaps with the orthographic projection of the liquid crystal layer on the first substrate. The overlap may mean that the signal line includes a signal segment located in the area where the liquid crystal layer is located, and a signal segment not located in the area where the liquid crystal layer is located. The signal line can load the signal and is responsible for transmitting the signal, wherein the transmitted signal can change the phase of the signal as the dielectric constant of the liquid crystal in the liquid crystal layer changes.

[0089] The cantilever branches in this example can be of micron scale or nanometer scale, such as MEMS (Micro-Electro-Mechanical System) cantilever branches. The specific size scale can be determined according to the wavelength of the center frequency point of the antenna corresponding to its phase shift unit. Of course, no matter it is of micron scale or nanometer scale, its cantilever branches are configured as micro-electromechanical mechanical structures, thus having the characteristics of micro-electromechanical mechanical structures, such as short response time.

[0090] Among them, one connection method between the cantilever branch and the signal line can be that both ends of the cantilever branch are connected to the signal line. In this way, there can be a gap between the cantilever branch and the signal line so that the cantilever branch can vibrate in the thickness direction of the liquid crystal layer; another connection method can be that one end of the cantilever branch is connected to the signal line, and the other end is suspended in the air as a free end, so that the cantilever branch can vibrate in the thickness direction of the liquid crystal layer.

[0091] The cantilever branch can also be connected to a control circuit. Specifically, the control circuit can output an electrical signal for the cantilever branch, which can be a control voltage. When the control voltage is loaded onto the cantilever branch, the cantilever branch can vibrate in the thickness direction of the liquid crystal layer.

[0092] In this embodiment, the cantilever branch may or may not overlap with the liquid crystal layer. In the case of overlap, the cantilever branch can generate displacement in the thickness direction of the liquid crystal layer when it vibrates, thereby changing the thickness of the liquid crystal covered by the cantilever branch, so that the capacitance in the area changes within microseconds, thereby increasing the phase shift of the phase shift unit; in the case of no overlap, the cantilever branch can still generate displacement in the thickness direction of the liquid crystal layer, and because it can generate a microsecond response and is connected to the signal line, it can adjust the signal transmission of the signal line itself, bringing a microsecond response to the signal transmission, thereby improving the response speed of the phase shift unit.

[0093] In this embodiment, the length and width of the signal line, as well as the length and width of the cantilever branch, can be determined according to the operating wavelength of the center frequency point of the phase shift unit, and are not particularly limited here.

[0094] For example, as shown in Figures 1 and 2, a first substrate 11 and a second substrate 12 are arranged relative to each other, and a plurality of isolation columns can be provided between the first substrate 11 and the second substrate 12. The area enclosed by the plurality of isolation columns is filled with liquid crystal to form a liquid crystal layer 2. A signal transmission structure 3 is provided on the side of the first substrate 11 close to the liquid crystal layer 2. The signal transmission structure includes a signal line 31 and a cantilever branch 32 connected to the signal line; wherein the orthographic projection of the signal line on the first substrate overlaps with the liquid crystal layer, and the orthographic projection of the cantilever branch on the first substrate is covered by the liquid crystal layer. The cantilever branch can respond in microseconds under the drive of an electrical signal and then vibrate. The vibration can change the thickness of the liquid crystal layer covered by the cantilever branch, so that the capacitance of this area (the area where the dotted box in Figure 2 is located) can change in microseconds. As a result, the response time of the phase shift unit can be reduced. Since its capacitance changes in microseconds, the capacitance change causes the differential phase shift (phase shift amount) of the phase shift unit to change, thereby increasing the phase shift amount. As a result, the antenna system composed of this phase shift unit has higher beam pointing accuracy and overall efficiency.

[0095] As another example, referring to Figures 1 and 2, a first substrate and a second substrate are positioned relative to each other, with a plurality of spacer columns disposed between the first and second substrates. The area enclosed by the plurality of spacer columns is filled with liquid crystal to form a liquid crystal layer. A signal transmission structure is disposed on the side of the first substrate proximal to the liquid crystal layer. The signal transmission structure includes a signal line and a cantilever branch connected to the signal line. The orthographic projection of the signal line on the first substrate overlaps with the liquid crystal layer, while the orthographic projection of the cantilever branch on the first substrate does not overlap with the liquid crystal layer. This means that the cantilever branch can be mounted on the ends of the signal line that are away from the liquid crystal. Similarly, the cantilever branch can respond within microseconds when driven by an electrical signal. While this does not change the thickness of the liquid crystal layer, its microsecond response improves signal transmission along the signal line and thus the response speed of the phase shifter.

[0096] It can be seen that the phase shifter provided in this embodiment has a faster response rate and improved phase shift speed due to the microsecond-level response of the cantilever branches coupled to the signal lines in the signal transmission structure. In addition, by designing the position of the cantilever branches relative to the liquid crystal layer, it is possible to increase both the phase shift speed and the phase shift amount. As a result, the phase shifter can combine the advantages of microsecond-level rapid adjustment of the liquid crystal phase shifter and the microelectromechanical system, and thus the antenna system composed of this phase shifter can have higher beam pointing accuracy and overall efficiency.

[0097] In some examples, the signal line may be a microstrip line, a stripline, or other types of signal lines.

[0098] In some other examples, the size of the signal line in the extension direction may be greater than λ / 2, where λ is the wavelength of the center frequency.

[0099] As described above, the cantilever branches can be arranged directly opposite the liquid crystal layer, so that when the cantilever branches vibrate in the thickness direction of the liquid crystal, the thickness of the liquid crystal layer can be changed. Based on this, in some examples, a capacitor structure can be coupled to the signal transmission structure so that when the cantilever branches change the thickness of the liquid crystal layer, the capacitor structure converts the change in thickness into a change in capacitance, thereby achieving the above-mentioned embodiment of changing the thickness of the liquid crystal layer covered by the cantilever branches, so that the capacitance of this area (the liquid crystal layer covered by the cantilever branches) can change within microseconds to increase the phase shift.

[0100] Specifically, in this example, the orthographic projection of the cantilever branch on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate; wherein, the signal transmission structure is constructed with a capacitor structure, the two electrodes of the capacitor structure are arranged relative to each other in the thickness direction of the liquid crystal layer, and at least one electrode is a cantilever branch.

[0101] In this example, the cantilever branch can serve as an electrode of the capacitor structure. Since the cantilever branch can vibrate in the thickness direction of the liquid crystal layer, the cantilever branch is displaced in the thickness direction of the liquid crystal layer, thereby changing the distance between the two electrodes of the capacitor structure, thereby changing the capacitance. For example, the thickness of the liquid crystal region covered by the cantilever branch in the liquid crystal layer changes, which in turn causes a change in capacitance. The change in capacitance causes a change in the differential phase shift (phase shift amount), thereby increasing the phase shift amount while achieving a microsecond phase shift response.

[0102] In Example 1 of this example, the signal transmission structure can form a capacitor structure between the cantilever branch and the other structural layers with the help of other structural layers. Specifically, the capacitor structure can include cantilever branches and flat layers distributed on opposite sides of the thickness direction of the liquid crystal layer. In this way, one electrode of the capacitor structure is the cantilever branch, and the other electrode is the flat layer. Referring to Figure 3, a schematic cross-sectional structure diagram of a phase shift unit in Example 1 is shown. As shown in Figure 3, the signal transmission structure is located on either substrate of the two substrates, and one electrode of the capacitor structure is the cantilever branch, and the other electrode can be a flat layer. Therefore, when the cantilever branch generates vibration in the thickness direction of the liquid crystal layer, the thickness of the liquid crystal region between the cantilever branch and the flat layer can be changed, thereby causing the capacitance of this region to change, thereby increasing the phase shift amount.

[0103] In another specific example 2 of this example, a capacitor structure can be constructed by setting the positions of the signal line and the cantilever branch. Specifically, the capacitor structure may include cantilever branches and signal lines spaced apart in the thickness direction of the liquid crystal layer, and the cantilever branches and the signal lines may be located on the same substrate (the first substrate or the second substrate), so that one electrode of the capacitor structure is a cantilever branch, and the other electrode is a signal line. Referring to Figure 4, a schematic cross-sectional structure diagram of a phase shift unit in Example 2 is shown. As shown in Figure 4, the signal transmission structure is located on either substrate of the two substrates, and one electrode of the capacitor structure is a cantilever branch, and the other electrode can be a signal line. Thus, when the cantilever branch generates vibration in the thickness direction of the liquid crystal layer, the thickness of the liquid crystal region between the cantilever branch and the signal line can be changed, thereby causing the capacitance of this region to change, thereby increasing the phase shift amount.

[0104] In a specific example 3 of this example, the capacitor structure may include two cantilever branches spaced apart in the thickness direction of the liquid crystal layer. The two cantilever branches may be located on the first substrate and the second substrate. In this way, both electrodes of the capacitor structure are cantilever branches. Referring to FIG5 , a schematic cross-sectional structure diagram of the phase shift unit in Example 3 is shown. As shown in FIG5 , in this case, the cantilever branches included in the signal transmission structure itself form a capacitor structure.

[0105] The following is an illustrative description of the structures of the three examples above.

[0106] First, with respect to Example 1, in a further example of Example 1, the signal transmission structure may be located on the first substrate, and the phase shifter unit further includes a flat layer, which is located on the side of the second substrate close to the liquid crystal layer, and whose orthographic projection on the second substrate overlaps with the orthographic projection of the cantilever branch on the second substrate; wherein, one electrode of the capacitor structure is the cantilever branch, and the other electrode is the flat layer.

[0107] As shown in Figure 3, in Example 1, the signal transmission structure can be located on the side of the first substrate close to the liquid crystal layer, and a flat layer 40 is set on the second substrate. The capacitor structure formed between the flat layer 40 and the cantilever branch can be a flat capacitor.

[0108] In this example 1, one end of the cantilever branch can be connected to the signal line, and the other end can be a free end, thereby allowing the cantilever branch to vibrate in the thickness direction of the liquid crystal. Specifically, the cantilever branch can be connected to the signal line orthogonally or non-orthogonally, but as a branch of the signal line, the angle formed between it and the signal line may not be 0 degrees.

[0109] In this example 1, the side of the cantilever branch close to the first substrate can be filled with liquid crystal or not. When not filled with liquid crystal, a protective film layer can be set. On the one hand, the protective film layer can allow the cantilever branch to vibrate, and on the other hand, it can prevent the cantilever branch from excessive deformation.

[0110] Referring to FIG6 , a schematic top view of the phase shifter unit of Example 1 is shown. As shown in FIG6 and FIG3 , the signal transmission structure is disposed on the side of the first substrate close to the liquid crystal layer. A flat plate layer 40 is disposed on the second substrate. The orthographic projection of the flat plate layer on the second substrate can overlap with the orthographic projection of the cantilever branch 32 on the second substrate. One end of the cantilever branch is orthogonally connected to the signal line, and the other end of the cantilever branch is free. Thus, a flat plate capacitor structure can be formed between the cantilever branch 32 and the flat plate layer 40.

[0111] In another example of Example 1, referring to FIG7 , a schematic top view of the metal floor layer in the phase shift unit shown in FIG6 is shown. As shown in FIG7 , the flat plate layer may include:

[0112] The metal floor layer 41 has a slotted area 42 , wherein the orthographic projection of the slotted area 42 on the second substrate does not overlap with the orthographic projection of the cantilever branch 32 on the second substrate and covers the orthographic projection of the signal line 31 on the second substrate;

[0113] The metal isolation layer 43 is located on a side of the metal floor layer 41 close to the liquid crystal layer 2 . The orthographic projection of the metal isolation layer 43 on the second substrate 12 at least covers the orthographic projection of the cantilever branches 32 on the second substrate 12 .

[0114] The metal floor layer may be made of metal materials such as copper, silver, etc. The thickness of the metal floor layer may be 0.2 μm to 5 μm and less than 1 / 1000 of the working wavelength of the center frequency.

[0115] Among them, the groove area can refer to the isolation zone of the metal floor layer, which is used to insulate the metal floors on both sides, thereby making the metal floor layer have a certain pattern. When forming the metal floor layer on the second substrate, a mask plate with a corresponding pattern can be used.

[0116] Among them, the orthographic projection of the slotted area on the second substrate does not overlap with the cantilever branch, and covers the orthographic projection of the microstrip line on the second substrate. Since the orthographic projection of the slotted area of ​​the metal floor layer on the second substrate covers the signal line and does not overlap with the orthographic projection of the cantilever branch on the second substrate, the corresponding areas of the cantilever branch 32 and the metal floor layer 41 can be separated to avoid the formation of a flat plate capacitor between the two, and the corresponding areas of the cantilever branch and the metal floor layer are constructed as flat plate capacitors.

[0117] As shown in Figure 7, a metal isolation layer can be located on the side of the metal floor layer closest to the liquid crystal layer. The orthographic projection of the metal isolation layer on the second substrate at least covers the orthographic projection of the cantilever branch on the second substrate. Specifically, the metal isolation layer can be used to prevent the cantilever branch from being grounded. In addition, it can be used to isolate the cantilever branch from the metal floor layer. Specifically, the metal isolation layer can only cover the location of the cantilever branch, or it can be global, that is, covering the orthographic projection of the signal transmission structure on the second substrate, thereby reducing the number of process mask layers and thus reducing costs.

[0118] The metal isolation layer can be made of an insulating material. Referring to FIG8 , which shows a schematic diagram of the AA cross-sectional structure of the phase shifter shown in FIG7 , a metal floor layer is located on the side of the second substrate closest to the liquid crystal layer. A slotted area is provided on the metal floor layer. A metal isolation layer can then be provided on the side of the metal floor layer closest to the liquid crystal layer. The metal isolation layer may or may not cover the slotted area, but the orthographic projection of the metal isolation layer on the second substrate must cover the orthographic projection of the cantilever branch on the second substrate. The area indicated by the dotted box in FIG8 is the target area 21 covered by the cantilever branch in the liquid crystal layer. This area can be understood as the area between the cantilever branch and the metal isolation layer. When the cantilever branch vibrates in the thickness direction of the liquid crystal layer, the thickness of this target area 21 changes.

[0119] In this example, since the slotted area can separate the cantilever branch strips from the corresponding area of ​​the metal floor, the metal isolation layer can prevent the cantilever branch strips from being grounded, thereby ensuring the electrical performance of the capacitor structure in the phase shift unit.

[0120] In some examples of Example 1, the signal transmission structure includes two symmetrically arranged signal lines 31 , with a microstrip gap 33 between the two signal lines, and the cantilever branches 32 are distributed in the microstrip gap 33 or outside the microstrip gap 33 .

[0121] In this example, the sizes of the cantilever branches connected to the two signal lines may be different, thereby making the structures of the cantilever branches connected to the two signal lines inconsistent, and the size of the cantilever branches may include the length and / or width of the cantilever branches; in another implementation of this example, the sizes of the cantilever branches connected to the two signal lines may be consistent, thereby making the structures of the cantilever branches connected to the two signal lines consistent, and the size of the cantilever branches mentioned above may include the length and width of the cantilever branches.

[0122] Of course, in a further example, if the cantilever branches connected to the two signal lines are of the same size, the cantilever branches connected to the two signal lines can be symmetrically located on both sides of the signal lines. In other words, the cantilever branches are symmetrical with respect to the signal lines. This structure can reduce manufacturing difficulty and improve the manufacturing efficiency of the phase shift unit.

[0123] In this example, the cantilever branch may be orthogonal to the signal line. Specifically, one end of the cantilever branch may be connected to the signal line, and the other end may be a free end.

[0124] 9a and 9b , there are shown schematic top-view diagrams of two more phase-shifting units of Example 1. As shown in FIG9a , the signal transmission structure is located on the side of the first substrate close to the liquid crystal layer, wherein the structure includes two symmetrically arranged signal lines, each signal line is connected to a cantilever branch, one end of the cantilever branch is orthogonally connected to the signal line, and the other end is a free end, and the cantilever branch can be symmetrical with respect to the signal line; wherein the cantilever branches on the two signal lines are distributed outside the microstrip gap; as shown in FIG9b , different from FIG9a , the cantilever branches on the two signal lines are distributed within the microstrip gap, and the cantilever branches can be asymmetrical with respect to the signal line.

[0125] When the cantilever branches are located within the microstrip gap, in one example, the two cantilever branches can be spaced apart in the direction of the signal line. In other words, the two cantilever branches are arranged at intervals in the direction of the signal line. Figure 9b shows this situation. When this structure is used, since the cantilever branches are distributed within the microstrip gap, their wiring space is relatively small. If they are arranged at intervals in the direction of the signal line, the wiring space for each cantilever branch can be appropriately increased, thereby reducing the manufacturing difficulty.

[0126] Of course, in another example, the two cantilever branches may also be arranged at intervals in a direction orthogonal to the extension direction of the signal line.

[0127] When the cantilever branches are arranged in the microstrip gap, the interference of the cantilever branches on the signal line transmission can be reduced, which is more convenient for simulation design.

[0128] Among them, the size relationship between the microstrip line gap, signal line and cantilever branch can be set as follows:

[0129] In one configuration, as shown in FIG9a and FIG9b , the microstrip gap has a first size S in the target direction, and the signal line has a second size in the target direction; wherein both the first size and the second size are less than λ / 100, λ is the wavelength of the center frequency, and the target direction is an orthogonal direction to the extension direction of the signal line.

[0130] It should be noted that, in this example, the extension direction of the signal line shown in Figures 9a and 9b is the x direction in the figure, and the target direction is the y direction, and the extension direction of the signal line (x direction) is applicable to the extension direction of the signal line described in other examples of the present disclosure.

[0131] Assuming that the signal line has a second dimension W in the target direction, the first dimension S < λ / 100, and the second dimension W < λ / 100; wherein the first dimension and the second dimension may be different, specifically, the first dimension may be larger than the second dimension or smaller than the second dimension, but both are smaller than one percent of the wavelength of the center frequency.

[0132] In another setting, the target area 21 located between the cantilever branch and the flat layer in the liquid crystal layer has a target size in the thickness direction of the liquid crystal layer; wherein the ratio between the first size and the target size is greater than 0.005, and the ratio between the second size and the target size is less than 5.

[0133] For example, if the signal line has a second dimension W in the target direction and the target dimension is h_LCV, then S / h_LCV>0.005 and W / h_LCV<5. This shows that the first dimension of the microstrip gap in the target direction can be smaller than the thickness of the liquid crystal in the target area 21, while the second dimension of the signal line in the target direction can be larger than the thickness of the liquid crystal in the target area 21. That is, in this example, the spacing between signal lines can be smaller than the width of the signal line itself.

[0134] The size setting in this example can improve the signal transmission quality of the signal line.

[0135] In another setting, the cantilever branch can be orthogonal to the signal line, and the cantilever branch has a third dimension in the target direction and a fourth dimension in the orthogonal direction of the target direction; wherein, the third dimension and the fourth dimension are both less than λ / 10, λ is the wavelength of the center frequency, and the target direction is the orthogonal direction of the extension direction of the signal line.

[0136] In this setting, the cantilever branch can be located within the microstrip gap. When located within the microstrip gap, the third dimension and the fourth dimension of the cantilever branch can both be less than λ / 100, thereby matching the space of the microstrip gap; wherein, the arm branch can also be located outside the microstrip gap. When located outside the microstrip gap, the third dimension and the fourth dimension of the cantilever branch can both be less than λ / 10 and greater than λ / 100, thereby resulting in a larger capacitor structure.

[0137] Of course, in this example, the third dimension of the cantilever branch can be understood as the width of the cantilever branch, and the fourth dimension can be understood as the length of the cantilever branch, wherein the third dimension can be the same as or different from the fourth dimension, specifically, the third dimension can be larger than the fourth dimension.

[0138] As described above, in Example 2, one electrode of the capacitor structure is a cantilever branch, and the other electrode is a signal line. In one implementation structure of Example 2, the cantilever branch can be erected on the signal line and constructed as a membrane bridge, thereby forming a capacitor structure between the signal line and the cantilever branch.

[0139] Referring to Figure 10, a schematic cross-sectional structure diagram of a phase shift unit in Example 2 is shown. As shown in Figure 10, the signal transmission structure is located on the first substrate or the second substrate, and the signal line includes a first signal line 311, a second signal line 312, and a third signal line 313 connected between the first signal line 311 and the second signal line 312; wherein, the two ends of the cantilever branch 32 are respectively connected to the first signal line 311 and the second signal line 312, and are spaced apart from the third signal line 313 in the thickness direction of the liquid crystal layer, and the liquid crystal layer includes a liquid crystal region located within the space; then one electrode of the constituted capacitor structure is the cantilever branch, and the other electrode is the third signal line.

[0140] The interval in this example is the target area 21 shown above, as marked in FIG10 .

[0141] In this example, the first signal line, the second signal line, and the third signal line may be connected to each other, or the third signal line may be connected to either the first signal line or the second signal line. The dimensions of the first signal line and the second signal line in the thickness direction of the liquid crystal layer are both greater than the dimensions of the third signal line in the thickness direction of the liquid crystal layer. Of course, the dimensions of the first signal line and the second signal line in the thickness direction of the liquid crystal layer may be the same or different.

[0142] Among them, in the thickness direction of the liquid crystal layer, there is a gap between the cantilever branch and the third signal line. The liquid crystal located in the gap can change its thickness as the cantilever branch vibrates, thereby changing the size of the capacitance formed between the third signal line and the cantilever branch, thereby bringing about a fast and large phase shift.

[0143] It should be noted that in this example, the side of the cantilever branch away from the third signal line may be filled with liquid crystal or not. When liquid crystal is not filled, a protective film layer may be provided to prevent the cantilever branch from being damaged due to excessive deformation.

[0144] When manufacturing the phase shifter in this example, the signal transmission structure can be integrated with the substrate, eliminating the need for additional processing on the opposite substrate. For example, the opposite substrate does not need a metal pattern layer; it can simply serve as an encapsulation layer. For example, if the signal transmission structure is located on the side of the second substrate closest to the liquid crystal layer, it can be integrated with the second substrate, while the first substrate can function directly as an encapsulation layer without requiring additional processing. This reduces processing costs, streamlines the process, and reduces manufacturing complexity, improving efficiency.

[0145] The phase shift unit of this example can be used in a coplanar waveguide-based liquid crystal phase shifter, or in a coupled microstrip line liquid crystal phase shifter. Moreover, since no additional processing is required on the opposite substrate, when the liquid crystal box is aligned, there is no need to align the first substrate and the second substrate; they can be directly aligned and packaged, thereby greatly improving the processing yield and process stability of the product.

[0146] In this Example 3, one electrode of the capacitor structure is a cantilever branch, and the other electrode is also a cantilever branch. In one implementation structure of this Example 3, the signal transmission structure can be configured as a differential signal transmission structure, including two differential signal lines, and the cantilever branches can be mounted on the differential signal lines, so that the cantilever branches are located on opposite sides in the thickness direction of the liquid crystal layer, forming a capacitor structure between the cantilever branches.

[0147] In a specific structural implementation, referring to FIG11 and FIG12 , FIG11 shows a schematic top planar structural diagram of a phase shift unit in Example 3, and FIG12 shows a schematic cross-sectional structural diagram of the phase shift unit in FIG11 in a direction. As shown in FIG11 and FIG12 , the signal line may include a fourth signal line 314 located on a side of the first substrate 11 close to the liquid crystal layer 2, and a fifth signal line 315 located on a side of the second substrate 12 close to the liquid crystal layer 2; the cantilever branch 32 may include a first cantilever branch 321 connected to the fourth signal line 314, and a second cantilever branch 322 connected to the fifth signal line 315;

[0148] The orthographic projection of the first cantilever branch on the first substrate overlaps with the orthographic projection of the second cantilever branch on the first substrate, so that the first cantilever branch and the second cantilever branch form a capacitor structure.

[0149] The signal transmission structure is located on the first substrate and the second substrate, the signal line includes a fourth signal line and a fifth signal line, and a differential signal line is formed between the fourth signal line and the fifth signal line.

[0150] Specifically, the orthographic projection of the fourth signal line on the second substrate may overlap or not overlap with the orthographic projection of the fifth signal line on the second substrate. Both the fourth and fifth signal lines are connected to cantilever branches, which may be orthogonal or parallel to the connected signal lines.

[0151] Specifically, to form a capacitor structure, the orthographic projection of the first cantilever branch on the second substrate may overlap with the orthographic projection of the second cantilever branch on the second substrate. The overlap may mean that the orthographic projections of the two completely overlap or completely do not overlap.

[0152] Among them, the liquid crystal area covered by the overlapping area of ​​the cantilever branches on both sides of the liquid crystal layer is the target area 21, such as the area shown by the dotted box in Figures 11 and 12. The thickness of the liquid crystal in the target area 21 will vibrate with the vibration of the cantilever branches, thereby changing the thickness.

[0153] It should be noted that, in this example, the cantilever branches on both sides of the liquid crystal layer can be loaded with control voltages at the same time, thereby causing vibrations. The vibration amplitudes of the cantilever branches on both sides can be different, thereby causing the thickness of the target area in the liquid crystal layer to change.

[0154] In another example of Example 3, the fourth signal line and the fifth signal line may have multiple branches. In the case of including multiple branches, the cantilever branches may be connected to a side of the branches close to the liquid crystal layer.

[0155] 13 , a top plan view of another phase shifting unit of Example 3 is shown. As shown in FIG13 , the fourth signal line 314 includes a first main signal line 314 a and a first signal line branch 314 b connected to the first main signal line, and the fifth signal line 315 includes a second main signal line 315 a and a second signal line branch 315 b connected to the second main signal line.

[0156] The first cantilever branch 321 is connected to a side of the first signal line branch 314 b close to the liquid crystal layer, and the second cantilever branch 322 is connected to a side of the second signal line branch 315 b close to the liquid crystal layer.

[0157] As shown in FIG13 , the orthographic projection of the first main signal line on the second substrate does not overlap with the orthographic projection of the second main signal line on the second substrate, and the orthographic projection of the first signal line branch on the second substrate overlaps with the orthographic projection of the second signal line branch on the second substrate;

[0158] Among them, the first cantilever branch is overlapped on the side of the first signal line branch close to the liquid crystal layer. Specifically, one end of the first cantilever branch is overlapped with the first signal line branch, and the other end can be a free end. Similarly, the second cantilever branch is overlapped on the side of the second signal line branch close to the liquid crystal layer. Specifically, one end of the second cantilever branch is overlapped with the second signal line branch, and the other end can be a free end.

[0159] The first signal line branch may be orthogonal to the first main signal line, the second signal line branch may be orthogonal to the second main signal line, the first cantilever branch may be parallel to the connected first signal line branch, and the second cantilever branch may be parallel to the connected second signal line branch.

[0160] In one example, the first cantilever branch and the second cantilever branch are both arranged closer to the liquid crystal layer than the signal line, and the overlapping region therebetween may be an overlapping region formed by a portion that is not overlapped with the signal line branch.

[0161] In the phase-shifting unit of Example 3, the signal transmission structure is constructed as a differential structure, and cantilever branches can be arranged on the branches of the differential signal lines. The signal transmission structure can be integrated with the substrates (first and second substrates). This signal transmission line structure results in a higher FoM value for the phase-shifting unit, resulting in lower losses for the same designed phase shift. Furthermore, when aligning the liquid crystal cell, there is no need for precise alignment of the first and second substrates, reducing the difficulty of cell packaging and significantly improving the product's processing yield and process stability.

[0162] It should be noted that, in some examples, in Examples 1 to 3 above, the cantilever branches can be set up as follows: orthogonal to the signal line, and their dimensions include a third dimension in the target direction and a fourth dimension in the orthogonal direction of the target direction; wherein the third dimension and the fourth dimension are both less than λ / 10, where λ is the wavelength of the center frequency, and the target direction is the orthogonal direction of the extension direction of the signal line.

[0163] In this way, no matter which capacitor structure is used, the size of the cantilever branch can be determined according to the wavelength of the set center frequency point.

[0164] As described above, the cantilever branches can be arranged at the edge of the liquid crystal layer, without overlapping with the liquid crystal layer. In this example, the cantilever branches can be loaded at the beginning and end of the signal line. Specifically, referring to FIG14 , a top plan view of a phase shifter in another example is shown. As shown in FIG14 , the orthographic projection of the cantilever branches on the first substrate does not overlap with the orthographic projection of the liquid crystal layer on the first substrate. The cantilever branches are stacked on the side of the signal line closest to the liquid crystal layer and are parallel to the signal line.

[0165] In this example, the signal transmission structure can be provided on the first substrate or the second substrate. The signal line can be one or more, such as two. The two signal lines can be symmetrically arranged, as shown in FIG13 , which illustrates the case of two signal lines. When two signal lines are included, a cantilever branch can be overlapped on at least one of the signal lines, such as cantilever branches can be overlapped on both signal lines.

[0166] The cantilever branch is parallel to the signal line. Specifically, the extension direction of the signal line can be the same as the extension direction of the cantilever branch. Specifically, the size of the signal line in the target direction can be the same as the size of the cantilever branch in the target direction, thereby making the cantilever branch parallel to the signal line. Of course, the size of the signal line in the target direction can also be different from the size of the cantilever branch in the target direction.

[0167] In this example, the cantilever branches are attached to the signal line in an area outside the liquid crystal layer and arranged parallel to the signal line. This increases the total length of the signal line, thereby improving signal transmission. Furthermore, when driven by a control voltage, the cantilever branches can still vibrate in the thickness direction of the liquid crystal layer, with a microsecond response time, thus improving the phase shift response of the phase shifter.

[0168] In both Example 1 and this example, the signal lines can include two symmetrically arranged signal lines, and the cantilever branches connected to the two signal lines are symmetrically arranged relative to the signal lines. Specifically, as shown in Figures 9a and 14, a symmetrical structure can reduce the complexity of the manufacturing process and improve manufacturing efficiency.

[0169] In some other examples, cantilever branches can be loaded on the portion of the signal line located in the liquid crystal region to construct a capacitor structure, so that the cantilever branches are called an electrode of the capacitor structure. At the same time, cantilever branches can also be loaded on the portion of the signal line away from the liquid crystal region, such as loading on the head and tail ends of the signal line. In this way, the cantilever branches can include cantilever branches whose projections are located on the liquid crystal layer, and cantilever branches whose projections do not overlap with the liquid crystal layer. In this way, the length of the signal line can be increased to improve the signal quality, and the phase shift amount can be increased through the cantilever branches in the capacitor structure, and a phase shift with a microsecond response can be obtained.

[0170] In a further example, in order to protect the cantilever branches, a reverse stress layer can be set on the side of the first substrate and the second substrate close to the liquid crystal layer. The reverse stress layer can prevent the substrate from warping and protect the metal layer from cracking and improve the product yield, wherein the metal layer can include a signal transmission structure, a feeding structure, etc.

[0171] It should be noted that the above example 1 and example 2 can be combined according to actual conditions.

[0172] Specifically, a reverse stress layer is formed on a side of a target substrate adjacent to the liquid crystal layer. The target substrate includes at least one of a first substrate and a second substrate on which the signal transmission structure is formed. For example, if the signal transmission structure is disposed on the first substrate, the target substrate is the first substrate; if the signal transmission structure is disposed on the second substrate, the target substrate is the second substrate; and if the signal transmission structure is disposed on both the first and second substrates, the target substrate includes both the first and second substrates.

[0173] Of course, if the signal transmission structure is located in only one of the first and second substrates, a reverse stress layer can still be provided on both the first and second substrates on the side closest to the liquid crystal layer, thereby achieving comprehensive protection for the metal structure in the phase shifter. The reverse stress layer can be made of an inorganic material.

[0174] Several phase shifting units provided in this embodiment are exemplarily described below.

[0175] Phase shift unit A

[0176] FIG15 shows a schematic cross-sectional structure diagram of a phase shifter unit A. A top plan view of the phase shifter unit A can be seen in FIG9a . The phase shifter unit A includes a first substrate 11, a second substrate 12, and a liquid crystal layer 2 disposed between the first and second substrates. A signal transmission structure 30 is disposed on a side of the first substrate close to the second substrate. A flat panel layer 40 is disposed on the second substrate.

[0177] A reverse stress layer 13 made of an inorganic material is provided on both the first substrate and the second substrate near the liquid crystal layer;

[0178] The signal transmission structure includes two symmetrically arranged signal lines 31, a microstrip gap is formed between the two signal lines, and the signal lines are microstrip lines;

[0179] Each signal line is connected to a cantilever branch, which is orthogonal to the signal line. Specifically, one end of the cantilever branch is connected to the signal line, and the other end is suspended. The cantilever branch is connected to the side of the signal line close to the liquid crystal layer, and the orthographic projection of the cantilever branch on the second substrate is located within the orthographic projection of the liquid crystal layer on the second substrate and is located outside the microstrip gap.

[0180] Wherein, the first substrate and the second substrate are both glass substrates with a thickness of 100 microns;

[0181] The thickness of the liquid crystal layer is 2 μm, the thickness of the flat panel layer is 0.2 μm, and the thicknesses of the liquid crystal layer and the flat panel layer need to be less than 1 / 1000 of the wavelength of the center frequency.

[0182] As shown in FIG15 , the flat panel layer includes a metal floor layer 41 and a metal isolation layer 43 located on a side of the metal floor layer close to the liquid crystal layer. Slotted areas 42 are provided on the metal floor layer, and the orthographic projection of each slotted area on the second substrate coincides with the orthographic projection of the corresponding signal line on the second substrate. For details, see FIG16 , which shows a top-down plan view of the metal floor layer. The orthographic projection of the metal isolation layer on the second substrate covers the orthographic projection of the cantilever branch on the second substrate.

[0183] The radiation branches, the metal isolation layer and the metal floor layer form a flat plate capacitor, which can change the thickness of the liquid crystal layer in the target area, causing the thickness to change and then causing the capacitance to change.

[0184] The phase shift unit A is simulated. Specifically, based on HFSS simulation software analysis, it is found that the phase shift unit A has a phase shift greater than 100° at the design center frequency f0.

[0185] Phase shift unit B

[0186] 17 and 18 , FIG17 shows a schematic cross-sectional structure diagram of the phase shift unit B, and FIG18 shows a pattern layer of the metal floor layer in the phase shift unit B. As shown in FIG18 and 19 , unlike the phase shift unit A, the cantilever branches are located within the microstrip gap of the signal line. When this arrangement is adopted, the cantilever branches connecting the two signal lines are spaced apart in the extension direction of the signal line.

[0187] Phase shift unit C

[0188] As shown in FIG16 , the system includes a first substrate, a second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, and the signal transmission structure is disposed on a side of the second substrate close to the liquid crystal layer;

[0189] A reverse stress layer is provided on each of the first substrate and the second substrate on a side close to the liquid crystal layer. The reverse stress layer is made of an inorganic material, and a signal transmission structure is provided on a side of the reverse stress layer close to the liquid crystal layer.

[0190] In which, the signal transmission structure includes a first signal line, a second signal line and a third signal line. The size of the first signal line in the thickness direction of the liquid crystal layer and the size of the second signal line in the thickness direction of the liquid crystal layer are both larger than the size of the third signal line in the thickness direction of the liquid crystal layer, and the size of the first signal line in the thickness direction of the liquid crystal layer and the size of the second signal line in the thickness direction of the liquid crystal layer can be the same.

[0191] The cantilever branch is overlapped between the first signal line and the second signal line, and is spaced apart from the third signal line, and is filled with liquid crystal in the space;

[0192] The thickness of the liquid crystal is 10 μm, and the thickness of the liquid crystal layer is less than 1 / 1000 of the wavelength of the center frequency.

[0193] Phase shift unit D

[0194] 13 , the system includes a first substrate, a second substrate, and a liquid crystal layer disposed between the first substrate and the second substrate, and the signal transmission structure is disposed on a side of the second substrate close to the liquid crystal layer;

[0195] A reverse stress layer is provided on each of the first substrate and the second substrate on a side close to the liquid crystal layer. The reverse stress layer is made of an inorganic material, and a signal transmission structure is provided on a side of the reverse stress layer close to the liquid crystal layer.

[0196] Wherein, the signal transmission structure includes a fourth signal line and a fifth signal line, and a differential signal line is formed between the fourth signal line and the fifth signal line;

[0197] The fourth signal line includes a first main signal line and a first signal line branch connected to the first main signal line, and the fifth signal line includes a second main signal line and a second signal line branch connected to the second main signal line.

[0198] Among them, the first signal line branch overlaps the first cantilever branch on the side close to the liquid crystal layer, and the second signal line branch overlaps the second cantilever branch on the side close to the liquid crystal layer; the orthographic projection of the first cantilever branch on the second substrate overlaps with the orthographic projection of the second cantilever branch on the second substrate.

[0199] The thickness of the liquid crystal is 15 μm, and the thickness of the liquid crystal layer is less than 1 / 1000 of the wavelength of the center frequency.

[0200] In this embodiment, the process steps for producing the phase shift unit of the above example may include: ① substrate input and cleaning; ② metal magnetron sputtering / electroplating MTD-Cu / Mo-Al / Ag; ③ CF film production process: cleaning, glue coating, Photo, development, cleaning, and post-baking; ④ Strip peeling; ⑤ spacer column preparation: CF film production process * 2; ⑥ testing the spacer column height; ⑦ CELL section process: PI, Rubbing, glue coating, ODF alignment, liquid crystal filling, vacuum annealing, ⑧ cutting and molding; ⑨ testing.

[0201] Based on the same inventive concept, the present disclosure also provides a phase shifter array, as shown in Figures 19a and 19b, which respectively show top-view structural schematic diagrams of two phase shifter arrays, as shown in Figures 19a and 19b, including multiple phase shifter units 100; wherein, the multiple phase shifter units 100 are arranged in an array, and the signal transmission structures of the multiple phase shifter units located in the same row or column share the same signal line 31.

[0202] The phase shift unit described in this embodiment is any exemplary phase shift unit in the above-mentioned phase shift unit embodiments.

[0203] As shown in Figure 19a, taking the above-mentioned phase shift unit A as an example, it includes multiple phase shift units, the phase shift unit has a capacitor structure, and is the capacitor structure in Example 1. As shown in Figure 19b, taking the above-mentioned phase shift unit C as an example, it includes multiple phase shift units, the phase shift unit has a capacitor structure, and is the capacitor structure in Example 3.

[0204] Multiple phase shifting units can be arranged in an array. Figure 19a only illustrates a column-based arrangement. The signal transmission structures of multiple phase shifting units in the same row or column share the same signal line. Specifically, the signal transmission structures of the phase shifting units in each row or column can share the same signal line, or the signal transmission structures of the phase shifting units in each column can share the same signal line. This allows the cantilever branches of different phase shifting units in the same row or column to be connected to the same signal line.

[0205] Among them, the signal transmission structures in different phase shift units are the same, such as signal transmission structures with capacitor structures or signal transmission structures without capacitor structures. Referring to FIG20 , an equivalent circuit diagram of a phase shifter array is shown, and as shown in FIG21 , the signal transmission structure is constructed with a capacitor structure. In FIG20 , C1ΔZ~C n ΔZ is the equivalent capacitance of each capacitance structure of the n phase shift units.

[0206] In one example of this embodiment, the signal transmission structure in the phase shift unit can be constructed with a capacitor structure. In this case, the sizes of the cantilever branches in different phase shift units are different, and the sizes include a third size in the target direction and / or a fourth size in the orthogonal direction of the target direction, and the target direction is the orthogonal direction of the extension direction of the signal line.

[0207] In this example, the capacitor structures constructed by different phase shifting units are consistent, such as the capacitor structure in the above example 1, or the capacitor structure in the above example 2, or the capacitor structure in the above example 3.

[0208] Since all cantilever branches need to be connected to a signal line and share a common signal line, the cantilever branches of multiple phase shifting units sharing the same signal line may have different sizes. Specifically, the sizes may include a third size in a target direction and / or a fourth size in a direction orthogonal to the target direction, where the target direction is a direction orthogonal to the extension direction of the signal line.

[0209] FIG21 illustrates a variation of the phase shifter array shown in FIG19a. As shown in FIG21 , the cantilever branches of different phase shifters sharing the same signal line have different third and fourth dimensions. More specifically, the cantilever branches of the phase shifters can have a periodic structure along the direction from the end of the signal line to the middle of the signal line, while the fourth dimension can increase sequentially.

[0210] The phase shifter array of this embodiment can be used for phase shifter impedance matching and reduce device insertion loss because the size of the cantilever branches can be different according to different phase shift units.

[0211] In another example of this embodiment, the signal transmission structure in the phase shifter unit may be configured with a capacitor structure. In this case, the cantilever branches of multiple phase shifters connected to the same signal line may have the same dimensions, including a third dimension in the target direction and a fourth dimension in a direction orthogonal to the target direction. Of course, in a further example of this embodiment, the cantilever branches of multiple phase shifters connected to the same signal line may also be spaced the same distance apart, so that the cantilever branches in the phase shifter array are equally spaced and of the same size.

[0212] As shown in FIG19a , a structure is shown in which the cantilever branches of multiple phase shifting units connected to the same signal line have the same size. With this exemplary structure, the cantilever branches are easy to process and have high fault tolerance and process yield.

[0213] Of course, in another example of this embodiment, the signal transmission structure in the phase shifter unit can be constructed with a capacitor structure. In this case, among the multiple phase shifters connected to the same signal line, the spacing between the cantilever branches in each two adjacent phase shifters is less than λ / 10; where λ is the wavelength corresponding to the center frequency.

[0214] In this example, the spacing between the cantilever branches in every two adjacent phase-shifting units may be the same or different, and the spacing is smaller than λ / 10.

[0215] More specifically, in a further implementation of this example, in a plurality of phase-shifting units connected to the same signal line, when the spacing between the cantilever branches in each two adjacent phase-shifting units is the same, the sizes of the cantilever branches in each two adjacent phase-shifting units in the plurality of phase-shifting units connected to the same signal line can be the same or different, which will not be elaborated here.

[0216] Of course, in some other examples, when the signal transmission structure is configured with a capacitor structure, each phase shift unit has a capacitor structure. In this case, the cantilever branches of multiple phase shift units connected to the same signal line can be constructed as a periodic structure.

[0217] In some further examples of this embodiment, referring to FIG22 , a top plan view schematic diagram of a phase shifter array is shown. As shown in FIG22 , a plurality of phase shifting units all have a signal transmission structure, wherein the signal transmission structure is not constructed with a capacitor structure, and its radiation branches can be connected to the outside of the liquid crystal layer, that is, the orthographic projection of the radiation branch on the second substrate does not overlap with the orthographic projection of the liquid crystal layer on the second substrate, thereby, a plurality of phase shifting units can share the radiation branch.

[0218] As shown in Figure 22, multiple phase shifting units share two signal lines, which are microstrip lines. Cantilever branches are connected to both ends of each signal line. The cantilever branches are located on the outside of the liquid crystal layer. In this way, the phase shift speed of the entire phase shifter array can be adjusted through the cantilever branches.

[0219] As shown in Figure 22, the substrate (first substrate or second substrate) provided with the signal transmission structure can be obtained by separating the special-shaped substrate, or by a cutting process, that is, the area corresponding to the liquid crystal layer is a whole piece of glass, and the cantilever branches are encapsulated outside the liquid crystal area.

[0220] In addition, in another example, compared to the method of Figure 20, the substrate (first substrate or second substrate) provided with the signal transmission structure can be a whole substrate, the cantilever branch is encapsulated outside the liquid crystal area, and the area where the cantilever branch is located does not need to be encapsulated, but is exposed to the outside, which can be used for testing and microscopic imaging analysis of the cantilever branch, and can be used for defect analysis and process verification of early processing technology.

[0221] Based on the same inventive concept, the present disclosure also provides a phased array antenna, which includes a plurality of phase shifting units and an antenna unit corresponding to each phase shifting unit.

[0222] Among them, since the cantilever branches in the phase shifter are on the micron or nanometer scale, the cantilever branches can respond quickly under the drive of electrical signals, so that the phase shifter can have the advantages of microsecond-level rapid adjustment of liquid crystal phase shifters and microelectromechanical systems, so that the phased array antenna composed of this phase shifter can have higher beam pointing accuracy and overall efficiency, which is very beneficial to improving the performance of passive phased array antennas based on liquid crystal phase shifters or multi-beam antennas based on liquid crystal phase shifters, and has high use value.

[0223] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0224] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity, or device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, commodity, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, commodity, or device that includes the element.

[0225] The above describes in detail a phase shifting unit, a phase shifter array, and a phased array antenna provided by the present disclosure. Specific examples are used herein to illustrate the principles and implementation methods of the present disclosure. The description of the above embodiments is only intended to help understand the method and core concept of the present disclosure. At the same time, for those skilled in the art, based on the concept of the present disclosure, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present disclosure.

[0226] Other embodiments of the present disclosure will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the following claims.

[0227] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

[0228] References herein to "one embodiment," "an embodiment," or "one or more embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Furthermore, please note that instances of the phrase "in one embodiment" do not necessarily all refer to the same embodiment.

[0229] In the description provided herein, numerous specific details are described. However, it is understood that embodiments of the present disclosure may be practiced without these specific details. In some instances, well-known methods, structures, and techniques are not shown in detail so as not to obscure the understanding of this description.

[0230] In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in the claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present disclosure may be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third etc. does not indicate any order. These words may be interpreted as names.

[0231] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present disclosure.

Claims

1. A phase shift unit, wherein: include: a first substrate; a second substrate, disposed opposite to the first substrate; a liquid crystal layer, disposed between the first substrate and the second substrate; as well as, a signal transmission structure, disposed on a side of the first substrate and / or the second substrate close to the liquid crystal layer, comprising at least one signal line and a cantilever branch connected to the signal line on a side close to the liquid crystal layer; The orthographic projection of the signal line on the first substrate overlaps with the orthographic projection of the liquid crystal layer on the first substrate, and the size of the cantilever branch is in the micrometer or nanometer order, and is configured to vibrate in the thickness direction of the liquid crystal layer under the drive of an electrical signal.

2. The phase shift unit according to claim 1, wherein: The orthographic projection of the cantilever branch on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate; The signal transmission structure is constructed with a capacitor structure, two electrodes of the capacitor structure are arranged opposite to each other in the thickness direction of the liquid crystal layer, and at least one of the electrodes is the cantilever branch.

3. The phase shift unit according to claim 2, wherein: The signal transmission structure is located on the first substrate, and the phase shifting unit further includes: a flat panel layer located on a side of the second substrate close to the liquid crystal layer, wherein an orthographic projection of the flat panel layer on the second substrate overlaps an orthographic projection of the cantilever branch on the second substrate; Wherein, one electrode of the capacitor structure is the cantilever branch, and the other electrode is the flat layer.

4. The phase shift unit according to claim 3, wherein: The flat plate layer comprises: a metal floor layer having a slotted area, wherein an orthographic projection of the slotted area on the second substrate does not overlap with an orthographic projection of the cantilever branch on the second substrate and covers an orthographic projection of the microstrip line on the second substrate; A metal isolation layer is located on a side of the metal floor layer close to the liquid crystal layer, and an orthographic projection of the metal isolation layer on the second substrate at least covers an orthographic projection of the cantilever branch on the second substrate.

5. The phase shift unit according to claim 3, wherein: The signal transmission structure includes two symmetrically arranged signal lines, a microstrip gap is provided between the two signal lines, and the cantilever branches are distributed within the microstrip gap or outside the microstrip gap. The phase shift unit according to claim 5 , wherein: The cantilever branches are distributed in the microstrip gap; wherein the cantilever branches to which the two signal lines are respectively connected are arranged at intervals in the extending direction of the signal line.

7. The phase shift unit according to claim 5, wherein: The microstrip gap has a first size in a target direction, and the signal line has a second size in the target direction; The first size and the second size are both smaller than λ / 100, λ is the wavelength of the center frequency, and the target direction is a direction orthogonal to the extension direction of the signal line.

8. The phase shift unit according to claim 7, wherein: A target region in the liquid crystal layer between the cantilever branch and the flat layer has a target size in the thickness direction of the liquid crystal layer; The ratio of the first size to the target size is greater than 0.005, and the ratio of the second size to the target size is less than 5.

9. The phase shift unit according to claim 2, wherein: The signal transmission structure is located on the first substrate or the second substrate, and the signal line includes a first signal line, a second signal line, and a third signal line connected between the first signal line and the second signal line; Two ends of the cantilever branch are connected to the first signal line and the second signal line respectively, and there is a gap between the cantilever branch and the third signal line in the thickness direction of the liquid crystal layer, and the liquid crystal layer includes a liquid crystal region located in the gap; Wherein, one electrode of the capacitor structure is the cantilever branch, and the other electrode is the third signal line.

10. The phase shift unit according to claim 2, wherein: The signal lines include a fourth signal line located on a side of the first substrate close to the liquid crystal layer, and a fifth signal line located on a side of the second substrate close to the liquid crystal layer; The cantilever branches include a first cantilever branch connected to the fourth signal line, and a second cantilever branch connected to the fifth signal line; The orthographic projection of the first cantilever branch on the first substrate overlaps with the orthographic projection of the second cantilever branch on the first substrate, so that the first cantilever branch and the second cantilever branch overlap. The cantilever branches constitute the capacitor structure.

11. The phase shift unit according to any one of claims 1 to 10, wherein: The orthographic projection of the cantilever branch on the first substrate does not overlap with the orthographic projection of the liquid crystal layer on the first substrate. The cantilever branch is stacked on a side of the signal line close to the liquid crystal layer and is parallel to the signal line.

12. The phase shift unit according to claim 3 or 11, wherein: The signal line includes two symmetrically arranged signal lines, and the cantilever branches connected to the two signal lines are symmetrically structured relative to the signal lines.

13. The phase shift unit according to claim 1, wherein: The phase shifting unit further includes: a reverse stress layer formed on a side of a target substrate close to the liquid crystal layer; wherein the target substrate includes at least one of the first substrate and the second substrate on which the signal transmission structure is formed; Wherein, the signal transmission structure is located on a side of the reverse stress layer close to the liquid crystal layer.

14. The phase shift unit according to claim 1, wherein: An orthographic projection of the cantilever branch on the first substrate is located within an orthographic projection of the liquid crystal layer on the first substrate and is orthogonal to the signal line. The cantilever branch has a third dimension in a target direction and a fourth dimension in a direction orthogonal to the target direction. The third dimension and the fourth dimension are both smaller than λ / 10, λ is the wavelength of the center frequency, and the target direction is a direction orthogonal to the extension direction of the signal line.

15. The phase shift unit according to claim 1, wherein: The dimension of the signal line in the extension direction is greater than λ / 2, where λ is the wavelength of the center frequency.

16. A phase shifter array, wherein: It comprises a plurality of phase shifting units as described in any one of claims 1 to 15; wherein the plurality of phase shifting units are arranged in an array, and the signal transmission structures of the plurality of phase shifting units located in the same row or the same column share the same signal line.

17. The phase shifter array according to claim 16, wherein: The orthographic projection of the cantilever branch in the phase shift unit on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate, and the signal transmission structure is constructed with a capacitor structure; The cantilever branches in different phase shifting units have different sizes, including a third size in a target direction and / or a fourth size in a direction orthogonal to the target direction, where the target direction is a direction orthogonal to the extension direction of the signal line.

18. The phase shifter array according to claim 16, wherein: The orthographic projection of the cantilever branch in the phase shift unit on the first substrate is located within the orthographic projection of the liquid crystal layer on the first substrate, and the signal transmission structure is constructed with a capacitor structure; Among the multiple phase shifting units sharing the same signal line, the spacing between the cantilever branches in every two adjacent phase shifting units is less than λ / 10; wherein λ is the wavelength corresponding to the center frequency.

19. The phase shifter array according to claim 18, wherein: The distances between the cantilever branches in every two adjacent phase-shifting units are the same.

20. A phased array antenna, wherein: The invention comprises a plurality of antenna array elements, and a plurality of phase shifting units as described in any one of claims 1 to 15 corresponding to each of the antenna elements.

Images