TWI898407B - Liquid crystal reflective array structure - Google Patents

Abstract

The present invention relates to a reflective surface structure. The structure includes a first substrate layer equipped with a first conductive patch, a second substrate layer equipped with the second conductive patch and the third conductive patch, and a liquid crystal layer. The liquid crystal layer is divided into multiple liquid crystal areas, and each liquid crystal area corresponds to a different substrate area. A reflective unit is formed through different substrate areas, the first conductive patch, the third conductive patch, or/and the second conductive patch. The first conductive patch and the second conductive patch or the first conductive patch and the third conductive patch have a voltage difference. The change in the voltage difference is used to turn the long-axis molecules of the liquid crystal in the liquid crystal area to individually change the phase of each reflective unit, thereby changing the reflection direction of the reflective unit.

Description

Liquid crystal array reflective structure

The present invention relates to a liquid crystal array reflective structure, and in particular to a liquid crystal array reflective structure having a high directivity reflective performance and capable of real-time reconstruction, with beamforming at any receiving end.

The invention of the frequency selective surface (FSS) has made it possible to design a periodic metal structure that can reduce signal interference, allow specific frequency bands to pass, filter out the remaining bands, and improve the signal-to-noise ratio. As a result, it has been widely used in equipment such as radar and antennas.

When the reflective frequency-selective surface array structure was discovered and applied to antennas, it provided the advantages of high gain, low structural complexity, low cost, and a planar structure. However, the fixed phase of the reflected wave became a disadvantage.

When electromagnetic waves propagate through the four major modes (direct radiation, diffraction, penetration, and reflection), they pass through obstacles such as walls, trees, cars, and even air in real life. These objects have dielectric constants and dielectric losses, which affect the efficiency of electromagnetic wave propagation.

In today's 5G era, higher mobile communication frequency bands offer faster speeds and greater bandwidth, but these bands also have poorer electromagnetic wave diffraction performance. This is why 5G communications require widespread deployment of base stations, which transmit signals indoors through base stations and antennas. 5G electromagnetic waves cannot directly diffract or penetrate walls to reach individual users. However, the cost of deploying base stations is often lower than expected.

Array antenna reflectors are used to enhance electromagnetic wave propagation efficiency. Their application in antennas can improve gain and directivity. This solves the problem of electromagnetic wave penetration loss. By varying the size of the antenna electrode units and thus the phase compensation, phase alignment is achieved, resolving beamforming and low gain issues.

However, the antenna electrode units of traditional reflectors cannot be resized at any time, and the fixed reflection phase becomes the main problem of array antenna reflectors.

Therefore, the liquid crystal array reflective structure of this invention can change the voltage by connecting to a voltage controller to change the dielectric constant of the liquid crystal, so that the adjusted phase of multiple reflective units can be focused on the receiving end. This will eliminate the need to produce a preset electromagnetic wave reflection direction by changing the size of the conductive patch, and therefore this invention should be an optimal solution.

A liquid crystal array reflective structure includes: a first substrate layer, on which a plurality of first conductive patches are arranged and arranged, wherein every two first conductive patches arranged one above the other are connected, and the first substrate layer is divided into a plurality of first surface units, and the first surface units correspond to the position of at least one first conductive patch; a second substrate layer, on which a plurality of second conductive patches or a plurality of third conductive patches are arranged and arranged on any surface, or a plurality of second conductive patches and a plurality of third conductive patches are arranged and arranged on different surfaces, wherein the position of the second conductive patch is corresponding to the position of the third conductive patch, and the second conductive patches are arranged and arranged on different surfaces, respectively. The substrate layer is divided into a plurality of second surface units, and the second surface units correspond to the positions of at least one second conductive patch and/or at least one third conductive patch; and a liquid crystal layer is located between the first substrate layer and the second substrate layer, and the liquid crystal layer has a grid spacer, which is used to separate a plurality of liquid crystal regions; wherein each liquid crystal region corresponds to the first surface unit of the first substrate layer and the second surface unit of the second substrate layer, and a reflective unit is formed by the first surface unit, the second surface unit, the first conductive patch, the third conductive patch and/or the second conductive patch.

More specifically, the second substrate layer is provided with at least one through-hole, the interior of which is filled with a conductive material for electrically connecting the second conductive patch and the third conductive patch, and the conductive material is a metal material with conductive properties.

More specifically, the liquid crystal array reflective structure further includes a first voltage controller and a second voltage controller. The first voltage controller is used to connect to a plurality of first conductive patches to provide a first voltage value, and the second voltage controller is used to connect to a plurality of second conductive patches or a plurality of third conductive patches to provide a second voltage value. The first voltage value of any first conductive patch has a voltage difference with the second voltage value of the second conductive patch or the third conductive patch corresponding to the first conductive patch.

More specifically, the change in the voltage difference is used to rotate the long axis molecules of the liquid crystal region of the reflective unit and change the dielectric constant of the liquid crystal region to individually change the phase of each reflective unit and thus change the reflection direction of the reflective unit.

More specifically, the first voltage controller is used to make the first conductive patches have different or the same first voltage values, and the second voltage controller is used to make the second conductive patches or the third conductive patches have different or the same second voltage values.

More specifically, the shapes of the first conductive patch, the second conductive patch, and the third conductive patch are rectangular, cross, frame, circular, or slit.

More specifically, the liquid crystal array reflective structure further includes a first alignment layer and a second alignment layer. The first alignment layer is located between the first substrate layer and the liquid crystal layer, and the second alignment layer is located between the liquid crystal layer and the second substrate layer.

More specifically, the first surface unit corresponds to a plurality of first conductive patches, which are connected vertically and horizontally to form a first conductive patch group. The horizontal spacing between every two first conductive patches in the first conductive patch group and each first conductive patch (the tilt of the center of the first conductive patch corresponds to the reflection angle) are used to change the electromagnetic wave emission direction of the reflective unit corresponding to the first surface unit.

More specifically, the center position of each liquid crystal area corresponds to the center position of the first surface unit and the center position of the second surface unit, and the center positions of the first conductive patch, the second conductive patch, and the third conductive patch correspond to the center position of the liquid crystal area.

Other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the preferred embodiments with reference to the drawings.

Please refer to Figures 1A to 1F, which are a schematic diagram of an exploded view, a schematic diagram of an assembled view, a schematic diagram of a cross-section, a schematic diagram of the scope of a first surface unit, and a schematic diagram of the scope of a second surface unit. As can be seen from the figures, the liquid crystal array reflective structure includes a first substrate layer 1, a second substrate layer 2, and a liquid crystal layer 3. The first substrate layer 1 and the second substrate layer 2 are parallel and opposite.

The first substrate layer 1 and the second substrate layer 2 are PCB boards, glass substrates, low dielectric loss boards or ceramic substrates.

The first substrate layer 1 and the second substrate layer 2 overlap and oppose each other, and have identical dimensions. The length and width of the first substrate layer 1 and the second substrate layer 2 can be set to half a wavelength of the transmission frequency (but actual use is not limited to half a wavelength), and the height of the first substrate layer 1 and the second substrate layer 2 can be set to a quarter wavelength of the transmission frequency (but actual use is not limited to a quarter wavelength). The transmission frequency is the wavelength of the designed frequency within the antenna transmission frequency in free space.

The second substrate layer 2 is provided with at least one through-hole 20, which is located at the center of the second surface unit 211. The through-hole 20 is filled with a conductive material 200 to electrically connect the second conductive patch 2111 and the third conductive patch 2211. The conductive material is a metal material with conductive properties. The second conductive patch 2111 and the third conductive patch 2211 are connected through the through-hole 20, so the voltage of the connected second conductive patch 2111 and the third conductive patch 2211 is the same.

This case has a surface unit on the surface of the substrate and a patch is set within the surface unit. However, to avoid overly complex lines in the drawings, the dotted lines of the surface unit are not shown in Figures 1A and 1B. Instead, only the patch within the surface unit is shown, and the explanations are shown in Figures 1D, 1E, and 1F, respectively.

The first substrate layer 1 is provided with a plurality of first surface units 111 on the first surface 11, and the plurality of first surface units 111 are arranged in an array to form a first surface layer.

As shown in FIG1D , the first surface unit 111 of the present invention is a preset space area used to allocate the available space of the first surface 11 and to facilitate the design of the size of the internal patch of the first surface unit 111. As shown in FIG1D , each first surface unit 111 has a first conductive patch 1111 (metal material, such as copper foil, with a thickness of 0.035 mm), and any two first conductive patches 1111 arranged vertically can be connected in series to form a first conductive patch group 112, and there is a gap between each two first conductive patch groups 112.

To further explain, since the first conductive patch group 112 is formed by multiple first conductive patches 1111 connected in series, only one first conductive patch 1111 is connected to the voltage source. The multiple first conductive patches 1111 in the first conductive patch group 112 all have the same first voltage value, and the multiple first conductive patches 1111 in different first conductive patch groups 112 can have the same or different first voltage values.

The second substrate layer 2 is provided with a plurality of second surface units 211 on the second upper surface 21 , and the plurality of second surface units 211 are arranged in an array to form a second surface layer.

As shown in FIG1E , the second surface unit 211 of the present invention is a preset space area used to allocate the available space on the second upper surface 21 , and at the same time, it is more convenient to design the size of the internal patch of the second surface unit 211 . As shown in FIG1E , each second surface unit 211 has a second conductive patch 2111 (metal material, such as copper foil), and there is a gap between every two second conductive patches 2111 .

The second substrate layer 2 is provided with a plurality of third surface units 221 on the second lower surface 22 , and the plurality of third surface units 221 are arranged in an array to form a third surface layer.

As shown in FIG1F , the third surface unit 221 of the present invention is a preset space area used to allocate the available space on the second lower surface 22 , and is more convenient for designing the size of the internal patch of the third surface unit 221 . As shown in FIG1E , each third surface unit 221 has a third conductive patch 2211 (metal material, such as copper foil), wherein the position of the second conductive patch 2111 is corresponding to the position of the third conductive patch 2211 , and there is a gap between every two third conductive patches 2211 .

As shown in FIG2A , the center pattern design of the first conductive patch 1111 is a rectangle (a), a frame (b), a cross slit (c), a cross (d), a diamond (e), or a circle (f). Since every two first conductive patches 1111 arranged vertically are connected in series, as shown in FIG1A , each first conductive patch 1111 has a rectangular line 1112 at its upper and lower ends.

As shown in FIG. 2B , the shapes of the second conductive patch 2111 are rectangle (a), frame (b), cross slit (c), cross (d), diamond (e), and circle (f).

As shown in Figure 3, the first surface unit 111 corresponds to the position of at least one first conductive patch 1111, and the length L and width W of the first surface unit 111 are greater than the length L1 and width L2 of the first conductive patch 1111 (and the length L1 plus the length of the two rectangular lines 1112 is equal to the length L. In addition, the length L and width W of the first surface unit 111 can also be designed to be equal to the length L1 and width L2 of the first conductive patch 1111), and the height of each second conductive patch 2111 is the same.

As shown in FIG3 , the second surface unit 211 corresponds to the position of the second conductive patch 2111 . As shown in the figure, since the length and width of the first surface unit 111 are the same as those of the second surface unit 211 , the length and width of the first surface unit 111 are used for comparison.

As shown in Figure 3, the length L and width W of the second surface unit 211 are greater than the length L2 and width W2 of the second conductive patch 2111 (but the length L and width W of the second surface unit 211 can also be designed to be equal to the length L2 and width W2 of the second conductive patch 2111), and the height of each second conductive patch 2111 is the same.

As shown in Figure 3, the third surface unit 221 corresponds to the position of the third conductive patch 2211. As shown in the figure, the length L and width W of the third surface unit 221 are greater than the length L3 and width W3 of the third conductive patch 2211 (but the length L and width W of the third surface unit 221 can also be designed to be equal to the length L3 and width W3 of the third conductive patch 2211), and the height of each third conductive patch 2211 is the same.

The content shown in Figure 3 is further explained as follows: (1) The boundary virtual frame of the surface unit of the reflective unit is the maximum side length (the length L and width W of the first surface unit 111, the second surface unit 211 and the third surface unit 221). (2) The third conductive patch 2211 (length L3, width W3) is smaller than the maximum side length. In addition to its function of external bias, it also prevents the loss of incident electromagnetic waves from transmission. (3) The second conductive patch 2111 (length L2, width W2) is smaller than or equal to the size of the third conductive patch 2211. The purpose is to prevent the conductive layers under adjacent units from being connected to each other. (4) The first conductive patch 1111 (length L1, width W1) is designed so that one side needs to extend to the maximum side length, and the rest is unlimited. The purpose is to connect the first conductive patches 1111 of adjacent units on one side to each other.

In this embodiment, the length and width of the multiple first conductive patches 1111 are designed to be the same (the thickness of each first conductive patch 1111 is also designed to be the same), but if applied to different embodiments, any one or more parameters of the length, width, and thickness of the multiple first conductive patches 1111 can be different.

In this embodiment, the length and width of the third conductive patch 2211 are designed to be greater than or equal to the length and width of the second conductive patch 2111 (the thickness of the second conductive patch 2111 and the third conductive patch 2211 are designed to be the same), but if applied to different embodiments, any one or more parameters of the length, width, and thickness can be different.

In addition, based on the reflection properties of electromagnetic waves, the first conductive patch 1111, the second conductive patch 2111, and the third conductive patch 2211 are generally made of a conductor, or a conductive material such as metal oxides such as indium tin oxide. Indium tin oxide is commonly used in ITO and is a transparent conductive material.

In addition, the first conductive patch 1111, the second conductive patch 2111, and the third conductive patch 2211 can all be used as reflective surfaces to prevent electromagnetic wave leakage.

In addition, there is no resistor connection between every two first conductive patch groups 112, and there is no resistor connection between every two first conductive patches 1111.

The liquid crystal layer 3 is located between the first substrate layer 1 and the second substrate layer 2 . A lattice spacer 31 is provided in the liquid crystal layer 3 . The lattice spacer 31 is used to separate a plurality of liquid crystal regions 32 .

In this embodiment, the liquid crystal layer 3 is made of thermotropic elongated nematic liquid crystal.

The center position of the liquid crystal region 32 corresponds to the center position of the first surface unit 111 and the center position of the second surface unit 211 , and the center positions of the first conductive patch 1111 , the second conductive patch 2111 , and the third conductive patch 2211 correspond to the center position of the liquid crystal region 32 .

The top and bottom surfaces of the liquid crystal layer 3 respectively have a first alignment layer 41 and a second alignment layer 42. The first alignment layer 41 is located between the first substrate layer 1 and the liquid crystal layer 3, and the second alignment layer 42 is located between the liquid crystal layer 3 and the second substrate layer 2. As shown in Figure 4, the alignment directions of the first alignment layer 41 and the second alignment layer 42 are the same, and the direction of the liquid crystal molecules in the liquid crystal layer 3 is also the same as the alignment directions of the first alignment layer 41 and the second alignment layer 42.

The first alignment layer 41 is a plane and is arranged parallel to the top surface of the liquid crystal layer 3 .

The second alignment layer 42 is a plane and is disposed parallel to the bottom surface of the liquid crystal layer 3 .

The first alignment layer 41 and the second alignment layer 42 are made of an insulating material and are coated using a rotary drum coating method. A coating machine is used to coat the alignment layers in the same direction, thereby generating a pre-tilt angle. This allows the long axis of the liquid crystal molecules to be aligned in the same direction as the alignment direction, so that they can be stably aligned when no voltage is applied (when no electric field is applied).

The thickness of the first alignment layer 41 and the second alignment layer 42 completely covers the first conductive patch 1111, the second conductive patch 2111, and the third conductive patch 2211. The hard material of the spacer can effectively prevent the conductive patches (the first conductive patch 1111, the second conductive patch 2111, and the third conductive patch 2211) from overlapping due to pressure and causing electrical connection. If the liquid crystal is in a sealed state, it will not overflow due to the application of external force and cause errors.

Because the liquid crystal in liquid crystal layer 3 is a phase-change material, it can undergo phase changes through electricity, heat, and light. In the embodiment of the present invention, electricity is used to induce phase change. The phase change occurs by changing the direction of the long axis of the liquid crystal molecules. When a bias voltage is applied to the upper and lower layers in opposite directions of the liquid crystal, the electric field becomes directional, and the long axis rotates due to the difference in the magnitude of the electric field. During this rotation, the dielectric constant changes. Simply put, within the effective applied voltage range of the liquid crystal, the maximum and minimum values are ɛ∥ and ɛ⊥, respectively. Δɛ is the parallel dielectric constant minus the perpendicular dielectric constant. When it is greater than 0, the liquid crystal is called a positive type liquid crystal, meaning that after the bias voltage is applied, the long axis of the liquid crystal molecules is aligned parallel to the direction of the electric field.

In this case, the alignment is determined by the electromagnetic wave's oscillation direction (incident direction). When the electromagnetic wave is incident (oscillated) horizontally, the liquid crystal alignment is also horizontal, and the electromagnetic wave experiences a horizontal dielectric constant. However, when the liquid crystal is deflected 90 degrees, becoming perpendicular to the incident electromagnetic wave, the electromagnetic wave experiences a perpendicular dielectric constant, altering both the phase and frequency.

If the liquid crystal is aligned vertically, the electromagnetic wave is also incident vertically. When the liquid crystal deflects, it becomes perpendicular to the incident electromagnetic wave. Therefore, no matter how the liquid crystal deflects, the electromagnetic wave will feel the vertical dielectric constant, and its characteristics will not change at all.

As shown in FIG1C , the liquid crystal array reflective structure can distinguish a plurality of reflective units 5 (only one reflective unit 5 is shown in the figure to avoid line confusion). The reflective units 5 are arranged from top to bottom to form a single unit with a reflective function, wherein each liquid crystal region 32 corresponds to the first surface unit 111, the second surface unit 211, and the third surface unit 221, and each first conductive patch 1111 corresponds to the second conductive patch 2111 and the third conductive patch 2211, so as to form the reflective unit 5 through the first surface unit 111, the second surface unit 211, the third surface unit 221, the first conductive patch 1111, the second conductive patch 2111, and the third conductive patch 2211.

As shown in Figures 5A-5C, the present embodiment can connect a first voltage controller 61 (or an independent voltage source capable of one-to-one voltage control or one-to-many voltage control) and a second voltage controller 62 (or an independent voltage source capable of one-to-one voltage control or one-to-many voltage control).

The first voltage controller 61 is used to connect to a plurality of first conductive patches 1111 to provide a first voltage value, and the second voltage controller 62 is used to connect to a plurality of third conductive patches 2211 to provide a second voltage value.

The first voltage controller 61 is used to enable the plurality of first conductive patches 1111 to have different or the same first voltage values. In this embodiment, each group of first conductive patches 1111 only needs to input a voltage, and the first voltage value is controlled by the first voltage controller 61.

The second voltage controller 62 is used to enable the plurality of third conductive patches 2211 to have different or the same second voltage values. In this embodiment, each third conductive patch 2211 needs to input a voltage and the second voltage value is controlled by the second voltage controller 62.

In this embodiment, when the dielectric constant of the liquid crystal does not change, that is, when the electric field is zero (the first voltage controller and the second voltage controller do not provide a bias), the incident electromagnetic wave will be reflected by the reflecting surface and will be scattered and reflected, and will not be able to focus on the receiving end.

Because the first voltage value and the second voltage value have a voltage difference, when the first voltage value and the second voltage value are different, an electric field is generated. The direction of the electric field changes according to the magnitude of the voltage difference, thereby causing the long-axis liquid crystal molecules in the liquid crystal region 32 of the reflective unit 5 to rotate and the dielectric constant of the liquid crystal region 32 to change. This individually changes the phase of each reflective unit 5 and changes the reflection direction of the reflective unit 5, thereby achieving phase compensation and real-time reconstruction of the receiving end phase, intelligently changing beamforming and directivity.

To further explain, the function of the alignment layer in this case is to uniformly align the liquid crystal molecules when the electric field is zero (the external voltage is zero). Therefore, when a bias voltage is applied starting from 0 volts, the liquid crystal molecules between each unit deflect, the dielectric constant changes, and the phase of the electromagnetic wave reflection also changes. Therefore, through this design, the reflection phase at the receiver can be easily calculated and combined with the phase value required for compensation of each unit. Through the voltage controller, the voltage difference is adjusted in real time to match the compensated phase value, achieving the effect of intelligent regulation, that is, any receiving end can achieve the expected antenna gain and directivity.

Therefore, by adjusting the voltage difference, the phase of each reflector unit 5 can be controlled as required and focused on the receiving end.

Further explaining FIG. 5A , the first conductive patches 1111 are connected in an array, and each of the arrayed conductive layers is externally connected to a voltage source from the first voltage controller 61 and has a first voltage value. As shown in the figure, from left to right, the first voltage values are V1 to V5.

Further explaining FIG. 5B , since the second voltage controller 62 is connected to each third conductive patch 2211 , the lines are very confusing, so a region is framed in the figure to indicate that “the second voltage controller 62 is connected to each third conductive patch 2211 .”

Further explaining Figure 5B, the second conductive patch 2111 and the third conductive patch 2211 are individually arranged and not connected to each other. The second conductive patch 2111 is connected to the third conductive patch 2211 through the through hole 20. The third conductive patch 2211 is also individually connected to the second voltage controller 62 and has a second voltage value. As shown in the figure, from the left to the right, the second voltage values are V6 to V30 respectively.

As can be seen from Figures 5A to 5C, this embodiment exemplifies the first reflective unit to the nth reflective unit (in this schematic diagram, only up to the 30th reflective unit, but not limited to this). The first voltage difference of the first unit is generated by the first conductive patch 1111 and the third conductive patch 2211 of the reflective unit 5. The voltage differences are 1(V1, V6), 2(V1, V7), 3(V1, V8), 4(V1, V9), 5(V1, V10), 6(V2, V11), 7(V2, V12), 8(V2, V13), 9(V2, V14), 10(V2, V15), 11(V3, V16), 12(V3, V17), 13(V3,V18) , 14(V3,V19) , 15(V3,V20) , 16(V4,V21) , 17(V4,V22) , 18(V4,V23) , 19(V4,V24) , 20(V4,V25) , 21(V5,V26) , 22(V5,V27) , 23(V5,V28) , 24(V5,V29) , 25(V5,V30) , and so on, where the number before the bracket is a certain unit representation, the left side of the bracket is the first voltage value of the first conductive patch 1111 arranged externally connected to the first voltage controller 61, and the right side is the second voltage value of the third conductive patch 2211 arranged individually and externally connected to the second voltage controller 62.

The above Figures 5A to 5C are an implementation mode. The first voltage controller 61 inputs a first voltage value to the first conductive patch group (including multiple first conductive patches 1111), and the second voltage controller 62 inputs a second voltage value to the individual third conductive patches 2211 to generate a reflector unit voltage difference schematic diagram as shown in Figure 5C (x in the figure represents the center position of each reflector unit). The above design will enable the voltage difference of each reflector unit to be individually controlled. For example, when adjusting the voltage difference of the sixth reflector unit (6(V2, V11)), only V11 needs to be adjusted. This will make it very convenient to individually control the phase of each reflector unit.

However, this case has another implementation mode, which is to use the third conductive patch 2211, like the first conductive patch 1111, using the structure shown in Figure 2A, and connect multiple third conductive patches 2211 in series through rectangular lines to form multiple third conductive patch groups.

Continuing with the embodiment of the specification [0059], the first voltage controller 61 can input a first voltage value to the first conductive patch group 112 (including a plurality of first conductive patches 1111), and the second voltage controller 62 can input a second voltage value to the plurality of third conductive patch groups to generate a voltage difference diagram of the reflective unit as shown in Figure 6 (x in the figure represents the center position of the reflective unit). From left to right, they are V1 to V5, and from top to bottom, they are V6 to V10. Their voltage differences are 1 (V1, V6), 2 (V1, V7), 3 (V1, V8), 4 (V1, V9), 5 (V1, V10), 6 (V2, V6), 7 (V2, V7), and 8 (V2, V8). , 9(V2,V9) , 10(V2,V10) , 11(V3,V6) , 12(V3,V7) , 13(V3,V8) , 14(V3,V9) , 15(V3,V10) , 16(V4,V6) , 17(V4,V7) , 18(V4,V8) , 19(V4,V9) , 20(V4,V10) , 21(V5,V6) , 22(V5,V7) , 23(V5,V8) , 24(V5,V9) , 25(V5,V10).

However, the design described in the specification [0059] will cause the voltage difference of each reflective unit to be dependent on each other. For example, when the voltage difference of the sixth reflective unit (6(V2, V6)) is to be adjusted, it will indirectly affect the reflective unit using V2 or the reflective unit using V6. In this way, it will be difficult and difficult to control the phase of each reflective unit individually. Therefore, it is better to control the second conductive patch 2111 and the third conductive patch 2211 individually rather than in groups. The technology of this case can be applied to either individual control or group control.

However, this case has another embodiment, as shown in FIG. 7 , in which the through hole 20 is not used. As mentioned above, the first voltage controller is connected to a plurality of first conductive patches 1111 to provide a first voltage value, and the second voltage controller is connected to a plurality of third conductive patches 2211 to provide a second voltage value, wherein the electric field of the third conductive patch 2211 is connected to the first conductive patch 111. 1 The electric field generates electric lines that deflect the liquid crystal. However, the electric field passes through the first substrate layer 1 and the second substrate layer 2. The first substrate layer 1 and the second substrate layer 2 are insulating materials, which will affect the electric field strength and will affect the electric fields of adjacent cells. Therefore, although it has the advantages of simple design and implementation, its performance is inferior to the structure described in [0020] of the specification. Since the substrate layer is an insulating material, the electric field strength is reduced.

If the structure of specification [0063] is to be adopted, the second substrate layer 2 can be omitted, and a plurality of second conductive patches 2111 do not need to be designed on the second upper surface 21 of the second substrate layer 2, as shown in FIG8 . This can reduce the difficulty and cost of the design.

In addition, the present invention has another embodiment, as shown in Figures 9A and 9B. In this embodiment, multiple first conductive patches 1111 are designed to be connected in series or in parallel within a reflective unit 7 (connected in series vertically via rectangular lines and then connected in parallel horizontally via rectangular lines). By changing the distance and angle θ between D1 and D5 (by changing the pattern of the conductive patches, the phase will have different phenomena at specific frequencies according to the principle of frequency selective surface), the direction of the reflected electromagnetic wave can be preset, so that the liquid crystal can be fine-tuned more accurately.

In addition, this case has another implementation method. When the number of third conductive patches 2211 is large, each third conductive patch 2211 must be connected to an external second voltage controller, which will increase the implementation difficulty. If this problem can be solved, a cluster design will be able to solve this problem. The phase difference of the electromagnetic wave reflected from each unit to the receiving end is extremely small, so a cluster design is possible.

The implementation is shown in FIG10A and is further described as follows: (1) A plurality of second conductive patches 2111 are grouped into a plurality of second conductive patch groups 212, wherein the second conductive patches 2111 in each second conductive patch group 212 are connected inwardly through rectangular lines, as shown in FIG10D. No two second conductive patch groups 212 are connected to each other. The pattern design is shown in FIG10C, and the pattern can be a plurality of circular connections (a), a plurality of rectangular connections (b), a plurality of diamond connections (c), and a plurality of frame connections (d). (2) A plurality of third conductive patches are replaced with a plurality of third conductive patch groups 222, wherein each third conductive patch group 222 becomes a large rectangle, as shown in FIG10F. The size of the third conductive patch group 222 does not exceed the maximum side length of the group unit. (3) Due to the grouped design of the second conductive patch group 212 and the third conductive patch group 222, the number of through-holes 20 can be reduced. As shown in FIG. 10E , at least one through-hole 20 is required in each region. Reducing the number of through-holes will prevent the substrate from being broken due to dense through-holes. (4) The grouped design of the second conductive patch group 212 and the third conductive patch group 222 can reduce the number of external second voltage controllers. (5) The first conductive patch group 112 itself is also a grouped design, which can also reduce the number of external first voltage controllers. (6) The first conductive patch group in this case can be connected to an external group voltage, as shown in Figure 10B. Therefore, the first conductive patch groups are all at the same voltage, which can be the same or different from the voltage of other first conductive patch groups. By changing the second voltage controller, the voltage of the third conductive patch is changed, so that a voltage difference is generated with the first conductive patch group. Each group has a different voltage difference and a different phase, thereby achieving the control of the electromagnetic wave reflection phase.

The advantages of the liquid crystal array reflective structure provided by the present invention compared with other conventional technologies are as follows: (1) The liquid crystal array reflective structure of the present invention can change the voltage through a voltage controller to change the dielectric constant of the liquid crystal, so that the adjusted phases of multiple reflective units can be focused on the receiving end. This eliminates the need to produce a preset electromagnetic wave reflection direction by changing the size of the conductive patch. (2) The adjusted phase of the present invention can be focused on the receiving end. More importantly, the voltage can be changed in real time through the voltage controller to achieve the performance of focusing at any receiving end. This is the principle of a smart reflective surface. (3) The present invention does not require the addition of resistors. Firstly, this is difficult to implement. Secondly, even if the voltage source is the same in each first conductive patch group, the individual bias of the third conductive patch can still achieve a different electric field for each unit. This means that there is no restriction on a gradually increasing or decreasing bias, but rather a bias of any size. (4) Unlike array reflective surfaces, the present invention does not require the size of the conductive patch to produce a preset electromagnetic wave reflection direction. In this case, the desired performance can be achieved by simply changing the dielectric constant of the liquid crystal. The design is also simple, and there is no need to calculate the size of the conductive patch for the preset reflection direction. In this embodiment, the size of the conductive patch is consistent. (5) In the present invention, since each reflective unit has a spacer, the electric field of each first conductive patch and the second conductive patch or the third conductive patch after bias is applied will not be affected by the vertical oblique electric field, making the phase more precise and the difference smaller. (6) The present invention uses a perforated substrate method to enable the liquid crystal layer sandwiched between the substrates to be individually biased between each unit, and uses spacers to separate the liquid crystal layer so that the vertical electric field direction of the molecules of the adjacent liquid crystal layer is not affected by the adjacent units. By compensating the reflection phase of each unit, the problem of traditional reflective array antennas that can only reflect a fixed phase is solved. (7) The present invention reduces the number of perforations required for the array through the design of unit clustering, while maintaining accuracy, improving cost, making the design easier, expanding the array, and preventing damage.

The present invention has been disclosed through the above embodiments, but they are not intended to limit the present invention. Anyone familiar with this technical field and having ordinary knowledge, after understanding the above technical features and embodiments of the present invention, can make certain changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of patent protection of the present invention shall be determined by the definition of the claims attached to this specification.

1: First substrate layer 11: First surface 111: First surface unit 1111: First conductive patch 1112: Rectangular line 112: First conductive patch assembly 2: Second substrate layer 20: Perforation 200: Conductive material 21: Second upper surface 211: Second surface unit 2111: Second conductive patch 212: Second conductive patch assembly 22: Second lower surface 221: Third surface unit 2211: Third conductive patch 222: Third conductive patch assembly 3: Liquid crystal layer 31: Grid spacer 32: Liquid crystal region 41: First alignment layer 42: Second alignment layer 5: Reflective unit 61: First voltage controller 62: Second voltage controller 7: Reflection unit

[Figure 1A] is a schematic exploded view of the liquid crystal array reflective structure of the present invention. [Figure 1B] is a schematic view of the assembled liquid crystal array reflective structure of the present invention. [Figure 1C] is a schematic cross-sectional view of the liquid crystal array reflective structure of the present invention. [Figure 1D] is a schematic view of the first surface unit of the liquid crystal array reflective structure of the present invention. [Figure 1E] is a schematic view of the second surface unit of the liquid crystal array reflective structure of the present invention. [Figure 1F] is a schematic view of the second surface unit of the liquid crystal array reflective structure of the present invention. [Figure 2A] is a schematic view of the shape of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 2B] is a schematic view of the shape of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 3] is a schematic diagram comparing different sizes of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 4] is a schematic diagram illustrating the alignment direction of the alignment layer of the liquid crystal array reflective structure of the present invention. [Figure 5A] is a schematic diagram illustrating the first voltage connection of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 5B] is a schematic diagram illustrating the second voltage connection of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 5C] is a schematic diagram illustrating the voltage difference of a reflective unit of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 6] is a schematic diagram illustrating the voltage difference of a reflective unit of another embodiment of the conductive patch of the liquid crystal array reflective structure of the present invention. [Figure 7] is a schematic diagram illustrating a cross-section of the conductive patch of the liquid crystal array reflective structure of the present invention without a perforation. [Figure 8] is a schematic cross-sectional view of a conductive patch without perforations and without a second conductive patch in the liquid crystal array reflective structure of the present invention. [Figure 9A] is a schematic diagram illustrating the first voltage connection of the first conductive patch in a series-parallel connection of the conductive patch in the liquid crystal array reflective structure of the present invention. [Figure 9B] is a schematic diagram illustrating the distance and angle adjustment of the first conductive patch in a series-parallel connection of the conductive patch in the liquid crystal array reflective structure of the present invention. [Figure 10A] is an exploded schematic view of another embodiment of the conductive patch in the liquid crystal array reflective structure of the present invention. [Figure 10B] is a schematic diagram illustrating the voltage difference of a reflective unit in another embodiment of the conductive patch in the liquid crystal array reflective structure of the present invention. [Figure 10C] is a schematic diagram illustrating the shape of the conductive patch in another embodiment of the liquid crystal array reflective structure of the present invention. [Figure 10D] is a schematic diagram illustrating the grouping of the second conductive patches in another embodiment of the liquid crystal array reflective structure of the present invention. [Figure 10E] is a schematic diagram illustrating the grouping of the perforations in another embodiment of the liquid crystal array reflective structure of the present invention. [Figure 10F] is a schematic diagram illustrating the grouping of the third conductive patches in another embodiment of the liquid crystal array reflective structure of the present invention.

1: First substrate layer

11: First Surface

1111: The first conductive patch

2: Second substrate layer

20: Perforation

200: Conductor material

21: Second upper surface

2111: Second conductive patch

22: Second lower surface

2211: Third Conductive Patch

31: Grid spacer

32: Liquid crystal area

41: First alignment layer

42: Second alignment layer

5: Reflection unit

Claims (8)

A liquid crystal array reflective structure includes: a first substrate layer having a plurality of first conductive patches arranged on one surface, wherein at least two first conductive patches arranged one above the other are connected, and the first substrate layer is divided into a plurality of first surface units, each of which corresponds to a position of at least one first conductive patch; and a second substrate layer having a plurality of second conductive patches or a plurality of third conductive patches arranged on any surface thereof. Alternatively, a plurality of second conductive patches and a plurality of third conductive patches are arranged on different surfaces, wherein the position of the second conductive patch is corresponding to the position of the third conductive patch, the second substrate layer is divided into a plurality of second surface units and a plurality of third surface units on different surfaces, and the second surface unit corresponds to at least one second conductive patch, and the third surface unit corresponds to the position of at least one third conductive patch; a liquid crystal layer is located on the A lattice spacer is provided between the first substrate layer and the second substrate layer, and the liquid crystal layer is provided with a lattice spacer for separating a plurality of liquid crystal regions; wherein each liquid crystal region corresponds to the first surface unit, the second surface unit, and the third surface unit, and a reflective unit is formed by the first surface unit, the second surface unit, the third surface unit, the first conductive patch, the third conductive patch, and/or the second conductive patch; and a A first voltage controller and a second voltage controller are provided. The first voltage controller is connected to a plurality of first conductive patches to provide a first voltage value. The second voltage controller is connected to a plurality of second conductive patches or a plurality of third conductive patches to provide a second voltage value. The first voltage value of any first conductive patch has a voltage difference with the second voltage value of the second conductive patch or the third conductive patch corresponding to the first conductive patch. The liquid crystal array reflective structure as described in claim 1, wherein the second substrate layer is provided with at least one through-hole, the interior of the through-hole is filled with a conductive material for electrically connecting the second conductive patch and the third conductive patch, and the conductive material is a metal material with conductive properties. A liquid crystal array reflective structure as described in claim 1, wherein the change in the voltage difference is used to rotate the long axis molecules of the liquid crystal region of the reflective unit and change the dielectric coefficient of the liquid crystal region to individually change the phase of each reflective unit to change the reflection direction of the reflective unit. A liquid crystal array reflective structure as described in claim 1, wherein the first voltage controller is used to make the plurality of first conductive patches have different or the same first voltage values, and the second voltage controller is used to make the plurality of second conductive patches or the plurality of third conductive patches have different or the same second voltage values. The liquid crystal array reflective structure as described in claim 1, wherein the shapes of the first conductive patch, the second conductive patch, and the third conductive patch are rectangular, cross-shaped, frame-shaped, circular, or slit. The liquid crystal array reflective structure as described in claim 1 further includes a first alignment layer and a second alignment layer, wherein the first alignment layer is located between the first substrate layer and the liquid crystal layer, and the second alignment layer is located between the liquid crystal layer and the second substrate layer. A liquid crystal array reflective structure as described in claim 1, wherein the first surface unit corresponds to a plurality of first conductive patches, and the plurality of first conductive patches are connected vertically and horizontally to form a first conductive patch group, wherein the lateral spacing between every two first conductive patches in the first conductive patch group and the central tilt angle of each first conductive patch are used to change the electromagnetic wave emission direction of the reflective unit corresponding to the first surface unit. The liquid crystal array reflective structure as described in claim 1, wherein the center position of each liquid crystal area corresponds to the center position of the first surface unit and the center position of the second surface unit, and the center positions of the first conductive patch, the second conductive patch, and the third conductive patch correspond to the center position of the liquid crystal area.