CN208818972U - Phase shifter and LCD antenna - Google Patents

Abstract

The utility model provides a kind of phase shifter and liquid crystal antenna, belongs to field of communication technology.The phase shifter of the utility model, comprising: the first substrate and the second substrate being oppositely arranged, and the liquid crystal layer between the first substrate and the second substrate；The first substrate includes: the first substrate, and the first electrode of the side positioned at first substrate close to the liquid crystal layer；The second substrate includes: the second substrate, and close to the second electrode of the side of the liquid crystal layer in second substrate；The phase shifter further includes the auxiliary capacitor connecting with first electrode.The phase shifter of the utility model combines low-pass filter and high-pass filter, to improve the adjustable extent of phase shifter, and the loss of phase shifter is improved within the scope of working frequency range, to increase the phase shift degree in specific loss.

Description

Phase shifter and LCD antenna

technical field

The utility model belongs to the technical field of communication, in particular to a phase shifter and a liquid crystal antenna.

Background technique

Phase shifter is a device that regulates the phase of electromagnetic waves. It is widely used in various communication systems, such as satellite communication, phased array radar, remote sensing telemetry, etc. The transmission characteristics of traditional microstrip phase shifters are low-pass characteristics. The periodic loading structure, by adjusting some of the parameters, can achieve the effect of phase shift, but this design method is that its loss is too large, the phase shift degree within the unit loss is low, and the loss generated when the large angle phase shift is realized Therefore, improving the phase shift degree of the device within the unit loss is a key point of the phase shifter.

Utility model content

The utility model aims to solve at least one of the technical problems existing in the prior art, and provides a phase shifter and a liquid crystal antenna which can reduce the loss.

The technical solution adopted to solve the technical problem of the present invention is a phase shifter, comprising: a first substrate and a second substrate arranged oppositely, and a liquid crystal layer located between the first substrate and the second substrate; The first substrate includes: a first substrate, and a first electrode located on a side of the first substrate close to the liquid crystal layer; the second substrate includes: a second substrate, and a first electrode located on the second substrate a second electrode close to one side of the liquid crystal layer; the phase shifter further includes an auxiliary capacitor connected to the first electrode.

Preferably, the first electrode includes: a microstrip line; the second electrode includes: a plurality of periodically arranged sub-electrodes; wherein, the microstrip line and the sub-electrodes are on the first substrate The orthographic projections on are at least partially overlapping.

Preferably, the microstrip line includes: a plurality of periodically arranged transmission units are arranged in sequence along its axial direction; a slit is defined between any two adjacent transmission units;

A plurality of auxiliary electrodes corresponding to the positions of the slits are arranged on the side of the second substrate close to the liquid crystal layer;

The orthographic projection of each auxiliary electrode on the first substrate covers its corresponding slit and a part of the position of the two adjacent transmission units that define the slit; wherein,

Each of the auxiliary electrodes and their orthographic projections on the first substrate cover part of the transmission unit to form the auxiliary capacitance.

Preferably, the auxiliary electrode and the sub-electrode are arranged in the same layer and have the same material.

Preferably, both the first pole piece and the second pole piece of the auxiliary capacitor are connected to the microstrip line.

Preferably, the first pole piece and the second pole piece of each auxiliary capacitor are connected on the same side of the microstrip line.

Preferably, one auxiliary capacitor is provided in an area defined by orthographic projections of any two adjacent sub-electrodes on the first substrate.

Preferably, the first pole piece and the second pole piece of the auxiliary electrode are integrally formed with the microstrip line.

Preferably, the microstrip line includes: a main body structure; the main body structure includes: a first side and a second side oppositely disposed along its axial direction; connected on the first side and the second side of the main body structure There are periodically arranged branch structures; the second electrode includes a pair of sub-electrodes; each of the sub-electrodes corresponds to the orthographic portion of the branch structure connected to the main structure on the first substrate overlapping.

Preferably, the main body structure includes: a plurality of periodically arranged transmission units are sequentially arranged along the axial direction of the main body structure; a slit is defined between any two adjacent transmission units; the transmission unit Both are connected with branch structures;

A plurality of auxiliary electrodes corresponding to the positions of the slits are arranged on the side of the second substrate close to the liquid crystal layer;

The orthographic projection of each auxiliary electrode on the first substrate covers the corresponding slit and the partial area of the two adjacent transmission units that define the slit; wherein,

Each auxiliary electrode and its orthographic projection on the first substrate cover the partial area of the transmission unit to form the auxiliary capacitor.

Preferably, the auxiliary electrode and the sub-electrode are arranged in the same layer and have the same material.

Preferably, a ground electrode is provided on a side of the first substrate away from the liquid crystal layer.

The technical solution adopted to solve the technical problem of the present invention is a liquid crystal antenna, which includes the above-mentioned phase shifter.

Description of drawings

1 is a top view of a phase shifter according to Embodiment 2 of the present invention;

2 is a side view of the phase shifter according to Embodiment 2 of the present invention;

Fig. 3 is the equivalent circuit model of the phase shifter of Embodiment 2 of the present utility model;

Fig. 4 is the transmission characteristic curve when the variable capacitance in the phase shifter of Embodiment 2 of the present utility model takes the minimum value;

Fig. 5 is the transmission characteristic curve when the variable capacitance in the phase shifter of Embodiment 2 of the present utility model takes the maximum value;

Fig. 6 is the top view of the existing phase shifter;

Fig. 7 is the equivalent circuit model of the existing phase shifter;

Fig. 8 is the transmission characteristic curve when the variable capacitance in the existing phase shifter takes the minimum value;

Fig. 9 is the transmission characteristic curve when the variable capacitance in the existing phase shifter takes the maximum value;

10 is a top view of the phase shifter according to Embodiment 3 of the present invention;

11 is a first side view of the phase shifter according to Embodiment 3 of the present invention;

12 is a second side view of the phase shifter according to Embodiment 3 of the present invention;

13 is an equivalent circuit model of the phase shifter of Embodiment 3 of the present invention;

14 is a top view of the phase shifter according to Embodiment 2 of the present invention;

15 is a side view of the phase shifter according to Embodiment 2 of the present invention;

FIG. 16 is an equivalent circuit model of the phase shifter according to the second embodiment of the present invention.

The reference numerals are: 10, first substrate; 1, microstrip line; 11, transmission unit, 12 ground electrode, 13, branch structure; 20, second substrate; 21, sub-electrode; 22, auxiliary electrode; 30, Liquid crystal layer; 31, liquid crystal molecules; C1, variable capacitor; C2, auxiliary capacitor; Q, slit.

Detailed ways

In order to make those skilled in the art better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Unless otherwise defined, the technical terms or scientific terms used in this embodiment should have the usual meanings that can be understood by those with ordinary skills in the technical field to which the present invention belongs. "First", "second" and similar words used in this embodiment do not denote any order, quantity or importance, but are only used to distinguish different components. "Comprises" or "comprising" and similar words mean that the elements or things appearing before the word encompass the elements or things recited after the word and their equivalents, but do not exclude other elements or things. Words like "connected" or "connected" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "Down", "Left", "Right", etc. are only used to represent the relative positional relationship, and when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

It will be understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, it can be "directly on" or "under" the other element, Or intermediate elements may be present.

Example 1:

This embodiment provides a liquid crystal phase shifter, including a first substrate and a second substrate disposed opposite to each other, and a liquid crystal layer located between the first substrate and the second substrate; wherein the first substrate includes: a first substrate, and A first electrode located on the side of the first substrate close to the liquid crystal layer; the second substrate includes: a second substrate, and a second electrode located on the side of the second substrate close to the liquid crystal layer; the first electrode and the second electrode are After a voltage is applied, an electric field is formed to deflect the liquid crystal molecules in the liquid crystal layer, thereby changing the dielectric constant of the liquid crystal layer, so as to change the phase of the microwave signal transmitted into the liquid crystal layer. In particular, in this embodiment, an auxiliary capacitor is also connected to the first electrode, so as to reduce the overall loss of the phase shifter, and at the same time, it can also improve the phase shift degree within the unit loss of the phase shifter.

In order to make the specific structure of the above liquid crystal phase shifter clearer, the phase shifter will be described in detail with reference to the following embodiments.

Example 2:

1 and 2, this embodiment provides a liquid crystal phase shifter, which includes a first substrate and a second substrate disposed opposite to each other, and a liquid crystal layer 30 located between the first substrate and the second substrate.

The first substrate includes: a first substrate 10, a first electrode located on the side of the first substrate 10 close to the liquid crystal layer 30, and a ground electrode 12 located on the side of the first substrate 10 away from the liquid crystal layer 30; specifically, wherein, The first electrode is a microstrip line 1; the microstrip line 1 includes a plurality of periodically arranged transmission units 11 arranged in sequence along its axial direction, and a slit is defined between any two adjacent transmission units 11 Q, that is, the transmission units 11 are arranged at intervals, and preferably the distances are the same.

The second substrate includes a second substrate 20 , and a second electrode located on a side of the second substrate 20 close to the liquid crystal layer 30 . The second electrode includes a plurality of periodically arranged sub-electrodes 21 ; each of the sub-electrodes 21 at least partially overlaps with the orthographic projection of the microstrip line 1 on the first substrate 10 on the first substrate 10 . A plurality of auxiliary electrodes 22 are also disposed on the second substrate, and each auxiliary electrode 22 corresponds to a slit Q on the first substrate 10 . Wherein, the orthographic projection of the auxiliary electrode 22 on the first substrate 10 covers the corresponding slit Q and a part of the position of the two adjacent transmission units 11 that define the slit Q; The orthographic projection on the first substrate 10 covers the partial position of the transmission structure, ie C2 shown in FIGS. 1 and 2 .

It should be noted here that, as shown in FIG. 1 , in order to achieve a better effect, each transmission unit 11 is arranged opposite to one sub-electrode 21 , but each transmission unit 11 is not limited to be arranged opposite to one sub-electrode 21 . In this embodiment, only this setting mode is used as an example for description.

In the phase shifter of this embodiment, the microstrip line 1 and the ground electrode 12 form a transmission structure for microwave signals, so that most of the microwave signals are transmitted in the first substrate 10 , and only a small part of the microwave signals are transmitted in the liquid crystal layer 30 However, the material of the first substrate 10 is usually selected from glass, ceramics, etc. These materials do not absorb microwave signals, so the loss of microwave signals during transmission can be greatly reduced. When a voltage signal is applied to the transmission unit 11 and the sub-electrode 21 in the phase shifter of this embodiment, an electric field will be generated between the layers where the transmission unit 11 and the sub-electrode 21 are located, and at the same time, the transmission unit 11 and the auxiliary electrode 22 overlap to form an auxiliary Capacitor C2, an electric field will also be generated between the two, and the generated electric field will deflect the liquid crystal molecules 31 in the liquid crystal layer 30, thereby changing the dielectric constant of the liquid crystal layer 30, and realizing the phase shift of the microwave signal in the liquid crystal layer 30, and then the liquid crystal The microwave signal in the layer 30 and the microwave signal in the first substrate 10 are alternately transmitted, so that the phase shift of the whole microwave signal is realized.

Wherein, each transmission unit 11 is equivalent to an inductance L, the overlapping of the transmission unit 11 and the sub-electrode 21 constitutes a variable capacitor C1, the overlapping of the auxiliary electrode 22 and the transmission unit 11 constitutes an auxiliary capacitor C2, and each transmission unit 11 and The ground electrodes 12 overlap to form an overlap capacitor C; as shown in FIG. 3 , FIG. 3 is the equivalent circuit model of FIG. 1 .

As shown in FIG. 6 , it is a phase shifter in the prior art, which is composed of a first substrate and a second substrate disposed opposite to each other, and a liquid crystal layer 30 located between them; wherein, the first substrate includes a first substrate 10, the microstrip line 1 located on the side of the first substrate 10 close to the liquid crystal layer 30, the ground electrode 12 located on the side of the first substrate 10 away from the liquid crystal layer 30; the second substrate includes: a second base, located on the second substrate 20 A plurality of sub-electrodes 21 are periodically arranged on the side close to the liquid crystal layer 30 . The microstrip line 1 is equivalent to an inductance L, the microstrip line 1 and the sub-electrode 21 overlap to form a variable capacitor C1, and the microstrip line 1 and the ground electrode 12 overlap to form an overlapped capacitor C; as shown in FIG. 7 , FIG. 7 is the equivalent circuit model of FIG. 6 .

It can be seen that the equivalent circuit model of the existing phase shifter constitutes a low-pass filter; while the equivalent circuit model of the phase shifter in this embodiment is equivalent to the microstrip line 1 in the technology An auxiliary capacitor C2 is connected in series, and the equivalent circuit model of the phase shifter in this embodiment constitutes a low-pass filter combined with a high-pass filter, which is equivalent to a band-pass filter. As shown in Figures 8 and 9, the transmission characteristic curve of the existing phase shifter during operation, wherein Figure 8 is the transmission characteristic curve of the existing phase shifter when the variable capacitor C1 is at the minimum value, and Figure 9 is the transmission characteristic curve of the existing phase shifter. The transmission characteristic curve when the variable capacitor C1 in the existing phase shifter is the maximum value; the transmission characteristic curve of the phase shifter in this embodiment is shown in Figure 4 and Figure 5 during operation, wherein Figure 4 is The transmission characteristic curve when the phase shifter variable capacitance C1 is at the minimum value in this embodiment, FIG. 5 is the transmission characteristic curve when the phase shifter variable capacitance C1 is at the maximum value in this embodiment; The loss of the phase shifter at point m ₁ (that is, the operating frequency point of the phase shifter) shown in Figure 4 and Figure 8 is the loss of the phase shifter when the operating frequency is 3.5GHz. It can be seen that this implementation The loss of the phase shifter in the example is still 0 at this operating frequency, while the operating loss of the existing phase shifter has begun to deviate from 0, and loss has begun to occur; for the same reason, comparing Figure 5 and Figure 10 is the same, in This will not be described in detail. Therefore, using the phase shifter in this embodiment can improve the adjustable range of the phase shifter, and improve the loss of the phase shifter within the operating frequency range, thereby increasing the phase shift degree within the unit loss.

Wherein, in the phase shifter of the present embodiment, the sub-electrodes 21 and the auxiliary electrodes 22 on the second substrate 20 are arranged in the same layer and have the same materials. At this time, the two parts of the structure can be prepared in one patterning process, so that the production efficiency of the phase shifter can be effectively improved, and the cost can be saved.

The widths of the slits Q between the transmission units 11 in the microstrip line 1 of this embodiment are the same, that is, the periodic arrangement of the transmission units 11 is arranged with the same pitch. The periodic arrangement is not limited to this, and each transmission unit 11 may also be arranged according to a preset arrangement rule.

Wherein, the spacing between the sub-electrodes 21 in the second electrode in this embodiment is the same, that is, the periodic arrangement of the sub-electrodes 21 is arranged in a manner of the same spacing, but the periodic arrangement of the sub-electrodes 21 It is not limited to this, and each sub-electrode 21 may also be arranged according to a preset arrangement rule.

Wherein, each transmission unit 11 is arranged corresponding to at least one sub-electrode 21 (in the figure, it is illustrated that each transmission unit 11 is arranged corresponding to one sub-electrode 21 as an example), and preferably each transmission unit 11 extends along the axis The direction is perpendicular to the axial direction of the sub-electrode 21 to ensure that the transmission unit 11 and the sub-electrode 21 have a large enough overlap area, so that after the transmission unit 11 and the sub-electrode 21 are applied with a voltage, the generated electric field can make the liquid crystal molecules 31 The deflection changes the dielectric constant of the liquid crystal layer 30 to realize the phase shift of the microwave signal.

Wherein, the first substrate 10 and the second substrate 20 can use a peeling substrate with a thickness of 100-1000 microns, a sapphire substrate, or a polyethylene terephthalate substrate with a thickness of 10-500 microns, Triallyl cyanurate substrate and polyimide transparent flexible substrate. Specifically, the first substrate 10 and the second substrate 20 may use high-purity quartz glass with extremely low dielectric loss. Compared with ordinary glass substrates, the use of quartz glass for the first substrate 10 and the second substrate 20 can effectively reduce the loss of microwaves, so that the phase shifter has low power consumption and high signal-to-noise ratio.

The materials of each transmission unit 11, ground electrode 12, sub-electrode 21, and auxiliary electrode 22 in the microstrip line 1 can be made of metals such as aluminum, silver, gold, chromium, molybdenum, nickel, or iron. Moreover, each transmission unit 11 in the microstrip line 1 can also be made of transparent conductive oxide.

The liquid crystal molecules 31 in the liquid crystal layer 30 are positive liquid crystal molecules 31 or negative liquid crystal molecules 31. It should be noted that when the liquid crystal molecules 31 are positive liquid crystal molecules 31, the liquid crystal molecules 31 in the specific embodiment of the present invention are longer than The included angle between the axial direction and the second electrode is greater than 0 degrees and less than or equal to 45 degrees. When the liquid crystal molecules 31 are negative liquid crystal molecules 31, the angle between the long axis direction of the liquid crystal molecules 31 and the second electrode in the specific embodiment of the present invention is greater than 45 degrees and less than 90 degrees, which ensures that after the liquid crystal molecules 31 are deflected, the change The dielectric constant of the liquid crystal layer 30 is used to achieve the purpose of phase shifting.

Embodiment 3:

10-12, this embodiment provides a liquid crystal phase shifter, which includes a first substrate and a second substrate disposed opposite to each other, and a liquid crystal phase shifter located between the first substrate and the second substrate The liquid crystal layer 30 .

The first substrate includes: a first substrate 10, a first electrode located on the side of the first substrate 10 close to the liquid crystal layer 30, and a ground electrode 12 located on the side of the first substrate 10 away from the liquid crystal layer 30; specifically, wherein, The first electrode is a microstrip line 1; the microstrip line 1 includes a main body structure, and the main body structure includes a first side and a second side oppositely arranged along its axial direction; the microstrip line 1 also includes a first side connected to the main body structure The branch structures 13 are periodically arranged on the side and the second side; and in order to facilitate the control of the phase shifter in this embodiment, the branch structures 13 connected on the first side and the second side of the main structure can be set as It is arranged symmetrically along the axial direction of the main structure. The main structure of the microstrip line 1 includes a plurality of periodically arranged transmission units 11 arranged in sequence along its axial direction, and a slit Q is defined between any two adjacent transmission units 11 . In this embodiment, the branch structures 13 are connected to the first side and the second side of each transmission unit 11 as an example; for the convenience of the following description, the first side and the second side of each transmission structure are connected to each other. A branch structure 13 is taken as an example for description. It should be understood that each transmission structure is arranged in sequence along the axial direction of the main structure, then the first side and the second side of the transmission structure are also the first side and the second side of the main structure.

The second substrate includes: a second substrate 20 and a second electrode located on the second substrate 20 . The second electrode includes a pair of sub-electrodes 21 , and one of the pair of sub-electrodes 21 is referred to as the first sub-electrode 21 and the other is referred to as the second sub-electrode 21 for convenience of description. The first sub-electrode 21 overlaps with the orthographic projection of the branch structure 13 connected to the first side of the main structure on the substrate, and the second sub-electrode 21 and the branch structure 13 connected to the second side of the main structure are on the first substrate 10 The orthographic projections on are partially overlapped. A plurality of auxiliary electrodes 22 are also arranged on the second substrate 20 ; the position of one auxiliary electrode 22 corresponds to the position of a slit Q on the first substrate 10 ; and each auxiliary electrode 22 is on the first substrate 10 The orthographic projection of C2 covers its corresponding slit Q, and the partial positions of the two adjacent transmission units 11 that define the slit Q; the auxiliary capacitor C2 and its orthographic projection on the first substrate 10 cover the transmission units Part of the position of 11 constitutes the auxiliary capacitor C2, that is, the C2 shown in the figure.

The phase shifter in this embodiment forms a microwave signal transmission structure through the main structure of the microstrip line 1 and the ground electrode 12, so that most of the microwave signals are transmitted in the first substrate 10, and only a small part of the microwave signals are transmitted in the liquid crystal layer. 30, and the material of the first substrate 10 is usually selected from glass, ceramics, etc. These materials do not absorb microwave signals, so the loss of microwave signals during transmission can be greatly reduced. When a voltage is applied to the sub-electrodes 21 in the microstrip line 1 and the second electrode in this embodiment, an electric field will be formed between each branch structure 13 and the sub-electrodes 21 arranged opposite to it, and the auxiliary electrodes 22 and the transmission unit 11 will form an electric field. An electric field will also be formed between the liquid crystal layers 30, so that the liquid crystal molecules 31 in the liquid crystal layer 30 are deflected, thereby changing the dielectric constant of the liquid crystal layer 30, and realizing the phase shift of the microwave signal in the liquid crystal layer 30, and then the microwave signal in the liquid crystal layer 30 and the first The microwave signals in the substrate 10 are alternately transmitted, so that the phase shift of the whole microwave signal is realized.

Wherein, each transmission unit 11 of the main structure is equivalent to an inductance L, each branch structure 13 is equivalent to a branch inductance L1, the branch structure 13 overlaps with the sub-electrode 21 to form a variable capacitor C1, the auxiliary electrode 22 and the transmission The overlapping of the units 11 constitutes an auxiliary capacitor C2, and each transmission unit 11 overlaps with the ground electrode 12 to constitute an overlapping capacitor C; as shown in FIG. 14 , which is the equivalent circuit model of FIG. 11 . The equivalent circuit model of the existing phase shifter is also shown in FIG. 7 .

It can be seen that the equivalent circuit model of the existing phase shifter constitutes a low-pass filter; while the equivalent circuit model of the phase shifter in this embodiment is equivalent to the microstrip line 1 in the technology An auxiliary capacitor C2 is connected in series, and the equivalent circuit model of the phase shifter in this embodiment constitutes a low-pass filter combined with a high-pass filter, which is equivalent to a band-pass filter. The equivalent circuit model of the phase shifter in this embodiment is roughly the same as the equivalent circuit model in Embodiment 1, the difference is only that each variable capacitor is connected in series with a branch inductance L1, but the output characteristic curve of this circuit model is the same as The output characteristic curves in Embodiment 1 are not very different, and are basically the same. That is to say, the use of the phase shifter in this embodiment can also improve the adjustable range of the phase shifter, and improve the phase shift within the operating frequency range. reducer losses, thereby increasing the degree of phase shift per unit loss.

Wherein, in the phase shifter of the present embodiment, the sub-electrodes 21 and the auxiliary electrodes 22 on the second substrate 20 are arranged in the same layer and have the same materials. At this time, the two parts of the structure can be prepared in one patterning process, so that the production efficiency of the phase shifter can be effectively improved, and the cost can be saved.

The widths of the slits Q between the transmission units 11 in the microstrip line 1 of this embodiment are the same, that is, the periodic arrangement of the transmission units 11 is arranged with the same pitch. The periodic arrangement is not limited to this, and each transmission unit 11 may also be arranged according to a preset arrangement rule.

Wherein, the distances between the branch structures 13 in the microstrip line 1 in this embodiment are the same, that is, the periodic arrangement of the sub-electrodes 21 is arranged with the same distance, but the periodic arrangement of the sub-electrodes 21 It is not limited to this, and each branch structure 13 can also be arranged according to a preset arrangement rule. In addition, each transmission unit 11 in this embodiment is connected to a substructure and is integrally formed with the transmission unit 11, that is, the two can be prepared in one process, so the preparation process can be simplified and the cost can be saved.

Wherein, the first substrate 10 and the second substrate 20 can use a peeling substrate with a thickness of 100-1000 microns, a sapphire substrate, or a polyethylene terephthalate substrate with a thickness of 10-500 microns, Triallyl cyanurate substrate and polyimide transparent flexible substrate. Specifically, the first substrate 10 and the second substrate 20 may use high-purity quartz glass with extremely low dielectric loss. Compared with ordinary glass substrates, the use of quartz glass for the first substrate 10 and the second substrate 20 can effectively reduce the loss of microwaves, so that the phase shifter has low power consumption and high signal-to-noise ratio.

The materials of each transmission unit 11, branch structure 13, ground electrode 12, sub-electrode 21, and auxiliary electrode 22 in the microstrip line 1 can be made of metals such as aluminum, silver, gold, chromium, molybdenum, nickel, or iron. . Moreover, each transmission unit 11 in the microstrip line 1 can also be made of transparent conductive oxide.

The liquid crystal molecules 31 in the liquid crystal layer 30 are positive liquid crystal molecules 31 or negative liquid crystal molecules 31. It should be noted that when the liquid crystal molecules 31 are positive liquid crystal molecules 31, the liquid crystal molecules 31 in the specific embodiment of the present invention are longer than The included angle between the axial direction and the second electrode is greater than 0 degrees and less than or equal to 45 degrees. When the liquid crystal molecules 31 are negative liquid crystal molecules 31, the angle between the long axis direction of the liquid crystal molecules 31 and the second electrode in the specific embodiment of the present invention is greater than 45 degrees and less than 90 degrees, which ensures that after the liquid crystal molecules 31 are deflected, the change The dielectric constant of the liquid crystal layer 30 is used to achieve the purpose of phase shifting.

Example 4:

14 and 15, a phase shifter is provided in this embodiment, which includes a first substrate and a second substrate disposed opposite to each other, and a liquid crystal layer 30 located between the first substrate and the second substrate.

The first substrate includes: a first substrate 10, a first electrode located on the side of the first substrate 10 close to the liquid crystal layer 30, and a ground electrode 12 located on the side of the first substrate 10 away from the liquid crystal layer 30; specifically, wherein, The first electrode is a microstrip line 1 ; an auxiliary capacitor C2 is also provided on the first substrate 10 , wherein the first pole piece and the second pole piece of the auxiliary capacitor C2 are both connected to the microstrip line 1 . It should be noted here that the first pole piece and the second pole piece of the auxiliary capacitor C2 are set opposite to each other, so it can be understood that the first pole piece and the second pole piece of the auxiliary capacitor C2 are connected to the microstrip line. 1 on the same side.

The second substrate includes a second substrate 20 , and a second electrode located on a side of the second substrate 20 close to the liquid crystal layer 30 . The second electrode includes a plurality of periodically arranged sub-electrodes 21 ; each of the sub-electrodes 21 at least partially overlaps with the orthographic projection of the microstrip line 1 on the first substrate 10 on the first substrate 10 . Wherein, an auxiliary capacitor C2 is provided in the region defined by the orthographic projections of any two adjacent sub-electrodes 21 on the first substrate 10 .

In the phase shifter of this embodiment, the microstrip line 1 and the ground electrode 12 form a transmission structure for microwave signals, so that most of the microwave signals are transmitted in the first substrate 10 , and only a small part of the microwave signals are transmitted in the liquid crystal layer 30 However, the material of the first substrate 10 is usually selected from glass, ceramics, etc. These materials do not absorb microwave signals, so the loss of microwave signals during transmission can be greatly reduced. When a voltage signal is applied to the microstrip line 1 and the sub-electrode 21 in the phase shifter of this embodiment, an electric field will be generated between the layer where the microstrip line 1 and the sub-electrode 21 are located, and the generated electric field will make the liquid crystal in the liquid crystal layer 30 The molecules 31 are deflected, thereby changing the dielectric constant of the liquid crystal layer 30 to realize the phase shift of the microwave signal in the liquid crystal layer 30, and then the microwave signal in the liquid crystal layer 30 and the microwave signal in the first substrate 10 are transmitted alternately, so that the overall microwave Phase shift of the signal.

The microstrip line 1 can be equivalent to an inductance L, the microstrip line 1 and the sub-electrode 21 overlap to form a variable capacitor C1, and the first pole piece and the second pole piece connected to the microstrip line 1 form an auxiliary capacitor C2 , the microstrip line 1 and the ground electrode 12 overlap to form an overlapping capacitance C; as shown in FIG. 16 , which is the equivalent circuit model of FIG. 15 . The equivalent circuit model of the existing phase shifter is also shown in FIG. 7 .

It can be seen that the equivalent circuit model of the existing phase shifter constitutes a low-pass filter; while the equivalent circuit model of the phase shifter in this embodiment is equivalent to the microstrip line 1 in the technology An auxiliary capacitor C2 is connected in parallel, and the equivalent circuit model of the phase shifter in this embodiment constitutes a low-pass filter combined with a high-pass filter, which is equivalent to a band-pass filter. The equivalent circuit model of the phase shifter in this embodiment is roughly the same as the equivalent circuit model in Embodiment 1. In this embodiment, an auxiliary capacitor C2 is connected in parallel with the microstrip line 1. The phase shifter in Embodiment 1 It is the microstrip line 1 connected in series with an auxiliary capacitor C2, but the output characteristic curve of this circuit model is not much different from the output characteristic curve in Example 1, which is basically the same, that is to say, the phase shifter in this example is used. The adjustable range of the phase shifter can also be improved, and the loss of the phase shifter is improved in the operating frequency range, thereby increasing the phase shift degree within the unit loss.

Among them, in the phase shifter of this embodiment, the microstrip line 1 on the first substrate 10 and the first pole piece and the second pole piece of the auxiliary capacitor C2 are integrally formed, that is, the two are arranged in the same layer, and The materials are the same, in this way, the two structures can be prepared in one process, which can reduce the process cost.

Wherein, the spacing between the sub-electrodes 21 in the second electrode in this embodiment is the same, that is, the periodic arrangement of the sub-electrodes 21 is arranged in a manner of the same spacing, but the periodic arrangement of the sub-electrodes 21 It is not limited to this, and each sub-electrode 21 may also be arranged according to a preset arrangement rule.

The axial direction of the sub-electrode 21 is perpendicular to the axial direction of the microstrip line 1 to ensure that the transmission unit 11 and the sub-electrode 21 have a large enough overlap area, so that after the transmission unit 11 and the sub-electrode 21 are applied with voltage, the The electric field can deflect the liquid crystal molecules 31 and change the dielectric constant of the liquid crystal layer 30 to realize the phase shift of the microwave signal.

Wherein, the first substrate 10 and the second substrate 20 can use a peeling substrate with a thickness of 100-1000 microns, a sapphire substrate, or a polyethylene terephthalate substrate with a thickness of 10-500 microns, Triallyl cyanurate substrate and polyimide transparent flexible substrate. Specifically, the first substrate 10 and the second substrate 20 may use high-purity quartz glass with extremely low dielectric loss. Compared with ordinary glass substrates, the use of quartz glass for the first substrate 10 and the second substrate 20 can effectively reduce the loss of microwaves, so that the phase shifter has low power consumption and high signal-to-noise ratio.

The materials of the microstrip, the ground electrode 12, the sub-electrode 21, the first pole piece and the second pole piece of the auxiliary capacitor C2 can all be made of metals such as aluminum, silver, gold, chromium, molybdenum, nickel or iron. Moreover, each transmission unit 11 in the microstrip line 1 can also be made of transparent conductive oxide.

The liquid crystal molecules 31 in the liquid crystal layer 30 are positive liquid crystal molecules 31 or negative liquid crystal molecules 31. It should be noted that when the liquid crystal molecules 31 are positive liquid crystal molecules 31, the liquid crystal molecules 31 in the specific embodiment of the present invention are longer than The included angle between the axial direction and the second electrode is greater than 0 degrees and less than or equal to 45 degrees. When the liquid crystal molecules 31 are negative liquid crystal molecules 31, the angle between the long axis direction of the liquid crystal molecules 31 and the second electrode in the specific embodiment of the present invention is greater than 45 degrees and less than 90 degrees, which ensures that after the liquid crystal molecules 31 are deflected, the change The dielectric constant of the liquid crystal layer 30 is used to achieve the purpose of phase shifting.

Example 5:

This embodiment provides a liquid crystal antenna, and the liquid crystal antenna includes any one of the liquid crystal phase shifters in Embodiments 1-3. Wherein, at least two patch units are further disposed on the side of the second substrate 20 away from the liquid crystal layer 30 , wherein the gap between each two patch units is set corresponding to the gap between the electrode strips. In this way, the microwave signal whose phase has been adjusted by any of the phase shifters in Embodiments 1-4 can be radiated from the gap between the patch units.

Of course, the liquid crystal antenna also includes a feeding interface for feeding the microwave signal in the cable to the microwave transmission structure, for example, the microstrip line 1 .

It can be understood that the above embodiments are only exemplary embodiments adopted to illustrate the principle of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims (13)

1. A phase shifter, comprising: the liquid crystal display panel comprises a first substrate, a second substrate and a liquid crystal layer, wherein the first substrate and the second substrate are oppositely arranged, and the liquid crystal layer is positioned between the first substrate and the second substrate; the first substrate includes: the liquid crystal display panel comprises a first substrate and a first electrode, wherein the first electrode is positioned on one side of the first substrate close to the liquid crystal layer; the second substrate includes: the second substrate and a second electrode are positioned on one side, close to the liquid crystal layer, of the second substrate; the phase shifter is characterized by further comprising an auxiliary capacitor connected with the first electrode.

2. The phase shifter according to claim 1, wherein the first electrode comprises: a microstrip line; the second electrode includes: a plurality of sub-electrodes arranged periodically; wherein the microstrip line and the orthographic projection of the sub-electrode on the first substrate are at least partially overlapped.

3. The phase shifter according to claim 2, wherein the microstrip line comprises: a plurality of transmission units which are periodically arranged are sequentially arranged along the axial direction of the transmission unit; a slit is defined between any two adjacent transmission units;

a plurality of auxiliary electrodes corresponding to the positions of the slits are arranged on one side, close to the liquid crystal layer, of the second substrate;

the orthographic projection of each auxiliary electrode on the first substrate covers the corresponding slit and the partial positions of two adjacent transmission units for limiting the slit; wherein,

each auxiliary electrode and the partial position of the transmission unit covered by the orthographic projection of the auxiliary electrode on the first substrate form the auxiliary capacitor.

4. The phase shifter according to claim 3, wherein the auxiliary electrode and the sub-electrode are disposed in the same layer and are made of the same material.

5. The phase shifter according to claim 2, wherein the first and second pole pieces of the auxiliary capacitance are both connected to the microstrip line.

6. The phase shifter according to claim 5, wherein the first and second pole pieces of each auxiliary capacitor are connected to the same side of the microstrip line.

7. The phase shifter according to claim 5, wherein one of the auxiliary capacitors is disposed in a region defined by orthographic projections of any two adjacent sub-electrodes on the first substrate.

8. The phase shifter according to claim 5, wherein the first and second pole pieces of the auxiliary capacitor and the microstrip line are integrally formed.

9. The phase shifter according to claim 2, wherein the microstrip line comprises: a body structure; the main body structure comprises: a first side and a second side disposed opposite to each other in an axial direction thereof; the first side and the second side of the main body structure are connected with branch structures which are periodically arranged; the second electrode comprises a pair of sub-electrodes; each sub-electrode is overlapped with the orthographic projection part of the corresponding branch structure connected with the main body structure on the first substrate.

10. The phase shifter of claim 9, wherein the body structure comprises: a plurality of transmission units which are periodically arranged are sequentially arranged along the axial direction of the main body structure; a slit is defined between any two adjacent transmission units; the transmission units are connected with branch structures;

a plurality of auxiliary electrodes corresponding to the positions of the slits are arranged on one side, close to the liquid crystal layer, of the second substrate;

the orthographic projection of each auxiliary electrode on the first substrate covers the corresponding slit and partial areas of two adjacent transmission units for limiting the slit; wherein,

each auxiliary electrode and a partial area of the transmission unit covered by the orthographic projection of the auxiliary electrode on the first substrate form the auxiliary capacitor.

11. The phase shifter according to claim 10, wherein the auxiliary electrode and the sub-electrode are disposed in the same layer and are made of the same material.

12. Phase shifter as in claim 1, characterized in that a ground electrode is provided on the side of the first substrate facing away from the liquid crystal layer.

13. A liquid crystal antenna comprising the phase shifter according to any one of claims 1 to 12.