Antenna array and method of operating the antenna array
The antenna unit with sidewall electrodes and controlled electric fields aligns liquid crystal molecules with signal polarization, addressing the dual-permittivity issue to enhance signal transmission and radiation intensity.
Patent Information
- Application Number
- JP2024096503
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2023-08-24
- Filing Date
- 2024-06-14
- Publication Date
- 2025-09-29
- Estimated Expiration
- 2044-06-14
AI Technical Summary
Liquid crystal molecules used in RF or antenna applications experience a dual-permittivity problem when the polarization direction of the signal is not parallel or perpendicular to the alignment of the liquid crystal layer, leading to lower-than-expected signal transmission direction or radiation intensity.
An antenna unit with a first and second substrate, sidewalls, a liquid crystal layer, and electrodes, where sidewall electrodes apply a horizontal electric field to align liquid crystal molecules parallel to the signal polarization, and a vertical electric field adjusts the equivalent dielectric constant to modulate signal transmission and radiation intensity.
The solution effectively aligns liquid crystal molecules with the signal polarization, alleviating the dual-permittivity issue and optimizing signal transmission and radiation intensity by providing a single dielectric constant.
Smart Images

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Abstract
Description
[Technical Field]
[0001] The present invention relates to an antenna unit, an antenna array and a method of operating an antenna array. [Background technology]
[0002] Liquid crystal molecules are anisotropic materials, with different dielectric constants along their long and short axes. When liquid crystals are used as tunable dielectric materials in radio frequency (RF) or antenna applications, if the polarization direction of the signal is not parallel or perpendicular to the alignment of the liquid crystal layer, a dual-permittivity problem may occur, resulting in a lower-than-expected signal transmission direction or radiation intensity. Summary of the Invention [Problem to be solved by the invention]
[0003] The present invention provides an antenna unit, an antenna array and a method for operating the antenna array, which can adjust the orientation of a liquid crystal layer. [Means for solving the problem]
[0004] In one embodiment of the present invention, the antenna unit includes a first substrate, a second substrate, a plurality of sidewalls, a liquid crystal layer, a first electrode, a second electrode, and a plurality of sidewall electrodes. The second substrate faces the first substrate. The plurality of sidewalls are supported between the first substrate and the second substrate. The liquid crystal layer is located between the first substrate, the second substrate, and the plurality of sidewalls. The first electrode is provided on the first substrate. The second electrode is provided on the second substrate and is electrically insulated from the first electrode. The plurality of sidewall electrodes are electrically insulated from each other and provided on the plurality of sidewalls, respectively. Here, the plurality of sidewall electrodes are electrically insulated from the first electrode and the second electrode.
[0005] In one embodiment of the present invention, an antenna array includes a plurality of first antenna units and at least one second antenna unit. Each of the plurality of first antenna units includes a first substrate, a second substrate, a plurality of sidewalls, a liquid crystal layer, a first electrode, a second electrode, and a plurality of sidewall electrodes. The second substrate faces the first substrate. The plurality of sidewalls are supported between the first substrate and the second substrate. The liquid crystal layer is located between the first substrate, the second substrate, and the plurality of sidewalls. The first electrode is provided on the first substrate. The second electrode is provided on the second substrate and electrically insulated from the first electrode. The plurality of sidewall electrodes are electrically insulated from each other and provided on the plurality of sidewalls, respectively. Here, the plurality of sidewall electrodes are electrically insulated from the first electrode and the second electrode. At least one second antenna unit is provided adjacent to the plurality of first antenna units. The at least one second antenna unit includes a third electrode and a fourth electrode, and the third electrode and the fourth electrode are provided on at least one of the first substrate and the second substrate.
[0006] In one embodiment of the present invention, a method for operating an antenna array includes providing an antenna array including the first antenna unit, applying a horizontal electric field to a liquid crystal layer using a plurality of sidewall electrodes, and applying a vertical electric field to the liquid crystal layer using a first electrode and a second electrode. [Effects of the Invention]
[0007] In the embodiment of the present invention, by providing a plurality of sidewall electrodes, the orientation of the liquid crystal layer can be adjusted according to the polarization direction of the signal, which contributes to alleviating the problem of double dielectric constant.
[0008] In order to make the above-mentioned features and advantages of the present invention clearer and easier to understand, the following embodiments are shown and described in detail with reference to the accompanying drawings. [Brief explanation of the drawings]
[0009] [Figure 1] 1 is a schematic diagram of an antenna unit according to an embodiment of the present invention; [Figure 2] 2 is a schematic diagram of the antenna unit of FIG. 1 taken along a cross section R1. [Figure 3] 2 is a schematic diagram of the antenna unit of FIG. 1 taken along cross section R2. [Figure 4] 2 is a schematic diagram of the antenna unit of FIG. 1 in the XY plane, showing the state when an electric field parallel to the X direction is applied to a plurality of liquid crystal molecules. [Figure 5] 1 ] A schematic diagram of the antenna unit in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied after the alignment process of multiple liquid crystal molecules in FIG. 4. [Figure 6] 1 ] A schematic diagram of the antenna unit in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied after the alignment process of multiple liquid crystal molecules in FIG. 4. [Figure 7] 1 ] A schematic diagram of the antenna unit in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied after the alignment process of multiple liquid crystal molecules in FIG. 4. [Figure 8] 2 is a schematic diagram of the antenna unit in the XY plane of FIG. 1, showing the state when an electric field parallel to the Y direction is applied to a plurality of liquid crystal molecules. [Figure 9] 7 is a schematic diagram of the antenna unit of FIG. 1 in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied after the alignment process of multiple liquid crystal molecules of FIG. [Figure 10] 7 is a schematic diagram of the antenna unit of FIG. 1 in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied after the alignment process of multiple liquid crystal molecules of FIG. [Figure 11] 7 is a schematic diagram of the antenna unit of FIG. 1 in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied after the alignment process of multiple liquid crystal molecules of FIG. [Figure 12] 2 is a schematic diagram of the antenna unit in the XY plane of FIG. 1, showing the state when an electric field parallel to the D direction is applied to multiple liquid crystal molecules. [Figure 13] 2 is another schematic view of the antenna unit of FIG. 1 at cross section R2. [Figure 14] FIG. 2 is a top view schematic diagram of an antenna array according to an embodiment of the present invention. [Figure 15] 15A to 15C are various cross-sectional schematic views taken along the line II' in FIG. 14. [Figure 16] 15A to 15C are various cross-sectional schematic views taken along the line II' in FIG. 14. [Figure 17] 15A to 15C are various cross-sectional schematic views taken along the line II' in FIG. 14. [Figure 18] 15A to 15C are various cross-sectional schematic views taken along the line II' in FIG. 14. [Figure 19] FIG. 10 is a top view schematic diagram of an antenna array according to another embodiment of the present invention. [Figure 20] FIG. 10 is a top schematic view of an antenna array according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION
[0010] Any directional terms such as "upper," "lower," "front," "rear," "left," "right," etc. referred to herein are used solely to refer to the orientation of the drawings, and therefore, the directional terms used are exemplary and not limiting of the present invention.
[0011] In the drawings, each figure illustrates the general features of a method, structure, or material used in a particular embodiment. However, these figures should not be construed as defining or limiting the scope or nature encompassed by these embodiments. For example, the relative size, thickness, and location of each film layer, region, or structure may be reduced or exaggerated for clarity.
[0012] In the following embodiments, the same or similar elements are denoted by the same or similar reference numerals, and redundant descriptions are omitted. Furthermore, the features of different embodiments can be combined with each other without contradiction, and simple equivalent changes and modifications made according to the scope of this specification or patent application still fall within the scope of this patent.
[0013] Terms such as "first" and "second" referred to in this specification or claims are used solely to name different components or distinguish between different embodiments or scopes, and are not used to limit the upper or lower limits of the number of components, nor are they used to define the manufacturing or arrangement order of components. Furthermore, "one component / film layer being disposed on (or above) another component / film layer" includes a situation where the component / film layer is directly disposed on (or above) the other component / film layer and the two components / film layers are in direct contact, and a situation where the component / film layer is indirectly disposed on (or above) the other component / film layer and one or more components / film layers exist between the two components / film layers.
[0014] FIG. 1 is a schematic diagram of an antenna unit according to an embodiment of the present invention. FIG. 2 is a schematic diagram of the antenna unit of FIG. 1 at cross section R1. FIG. 3 is a schematic diagram of the antenna unit of FIG. 1 at cross section R2. FIG. 4 is a schematic diagram of the antenna unit of FIG. 1 in the XY plane, showing the state when an electric field parallel to the X direction is applied to a plurality of liquid crystal molecules. FIGS. 5 to 7 are schematic diagrams of the antenna unit of FIG. 1 in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied to a plurality of liquid crystal molecules after the alignment process of FIG. 4. FIG. 8 is a schematic diagram of the antenna unit of FIG. 1 in the XY plane, showing the state when an electric field parallel to the Y direction is applied to a plurality of liquid crystal molecules. FIGS. 9 to 11 are schematic diagrams of the antenna unit of FIG. 1 in the XZ plane, showing the state when a vertical electric field (electric field parallel to the Z direction) gradually increasing from 0 is applied to a plurality of liquid crystal molecules after the alignment process of FIG. 7. Fig. 12 is a schematic diagram of the antenna unit of Fig. 1 in the XY plane, showing the state when an electric field parallel to the D direction is applied to multiple liquid crystal molecules. Fig. 13 is another schematic diagram of the antenna unit of Fig. 1 at cross section R2. Fig. 14 is a schematic top view of an antenna array according to an embodiment of the present invention. Figs. 15 to 18 are various schematic cross-sectional views taken along line I-I' of Fig. 14, respectively. Figs. 19 and 20 are schematic top views of antenna arrays according to other embodiments of the present invention.
[0015] 1 to 3, an antenna unit (e.g., also referred to as a first antenna unit) 1 may include, but is not limited to, a first substrate 10, a second substrate 11, a plurality of sidewalls 12, a liquid crystal layer 13, a first electrode 14, a second electrode 15, and a plurality of sidewall electrodes 16. If necessary, the antenna unit 1 may further include other components or film layers.
[0016] The first substrate 10 may be a rigid substrate or a flexible substrate, and the material of the first substrate 10 includes, but is not limited to, glass, ceramics, plastics, etc.
[0017] The second substrate 11 faces the first substrate 10. As shown in Fig. 1, the second substrate 11 is provided so as to overlap the first substrate 10 in the Z direction, for example. The second substrate 11 may be a rigid substrate or a flexible substrate. The material of the second substrate 11 includes, but is not limited to, glass, ceramics, plastic, or the like.
[0018] The side walls 12 are supported between the first substrate 10 and the second substrate 11, and the first substrate 10, the second substrate 11, and the side walls 12 enclose a space for accommodating the liquid crystal layer 13. Taking a hexahedral antenna unit as an example, the antenna unit 1 may include four side walls 12, such as a first side wall 12-1, a second side wall 12-2, a third side wall 12-3, and a fourth side wall 12-4. These side walls 12 are connected in pairs to form a frame, as shown in FIG. 3 . However, it should be understood that the number of side walls 12 of the antenna unit 1 can be changed according to actual needs and is not limited to four. Materials for the side walls 12 include, but are not limited to, a sealant. In some embodiments, the side walls 12 may be integrally formed.
[0019] The liquid crystal layer 13 is located between the first substrate 10, the second substrate 11, and the sidewalls 12. Although not shown in FIGS. 1 to 3 , the liquid crystal layer 13 may include a plurality of liquid crystal molecules, such as, but not limited to, a plurality of positive liquid crystal molecules. The liquid crystal molecules have a long axis and a short axis perpendicular to the long axis. When no external electric field is applied to the liquid crystal layer 13, the liquid crystal molecules exhibit, for example, a random tilt state without a specific tilt direction (when no alignment film is provided). On the other hand, when an external electric field is applied to the liquid crystal layer 13, the liquid crystal molecules tilt or rotate in the direction of the external electric field, and the long axes of the liquid crystal molecules are parallel or approximately parallel to the direction of the external electric field.
[0020] The first electrode 14 is provided on the first substrate 10. In some embodiments, as shown in FIG. 2 , the first electrode 14 may be provided on an inner surface S10-1 of the first substrate 10 (e.g., the surface of the first substrate 10 facing the second substrate 11) such that the first electrode 14 is located between the first substrate 10 and the liquid crystal layer 13, but is not limited to this. In other embodiments, although not shown, the first electrode 14 may be provided on an outer surface S10-2 of the first substrate 10 (e.g., the surface of the first substrate 10 opposite the second substrate 11) such that the first electrode 14 is located between the first electrode 14 and the liquid crystal layer 13. Examples of materials for the first electrode 14 include, but are not limited to, metals, alloys, or combinations thereof. In some embodiments, the first electrode 14 may be a ground electrode, or the first electrode 14 may be a full-surface electrode, but is not limited to this.
[0021] The second electrode 15 is disposed on the second substrate 11 and is electrically insulated from the first electrode 14. In some embodiments, as shown in FIG. 2 , the second electrode 15 may be disposed on an outer surface S11-2 of the second substrate 11 (e.g., the surface of the second substrate 11 opposite the first substrate 10) such that the second substrate 11 is positioned between the second electrode 15 and the liquid crystal layer 13, but is not limited to this. In other embodiments, although not shown, the second electrode 15 may be disposed on an inner surface S11-1 of the second substrate 11 (e.g., the surface of the second substrate 11 facing the first substrate 10) such that the second electrode 15 is positioned between the second substrate 11 and the liquid crystal layer 13. Examples of materials for the second electrode 15 include, but are not limited to, metals, alloys, or combinations thereof. In some embodiments, the second electrode 15 may be a patterned electrode, and the top view shape of the second electrode 15 may include, but is not limited to, a rectangle, a circle, an annulus, or a combination thereof.
[0022] The second electrode 15 overlaps the first electrode 14 in the Z direction, and the second electrode 15 and the first electrode 14 are separated by at least the liquid crystal layer 13 and are electrically insulated from each other. By independently controlling the voltages applied to the first electrode 14 and the second electrode 15, a perpendicular electric field (the electric field direction is parallel or approximately parallel to the Z direction) can be applied to the liquid crystal layer 13, thereby changing the equivalent dielectric constant of the antenna unit 1. Changing the equivalent dielectric constant of the antenna unit 1 can modulate design parameters such as the phase delay and / or radiation intensity of the signal SG (e.g., electromagnetic wave). In the case of an antenna array including multiple antenna units, this is equivalent to modulating the transmission (reflection) direction and / or radiation intensity of the signal SG. The electromagnetic wave may be a radio frequency, millimeter wave, terahertz (THz) wave, or electromagnetic wave in another frequency range.
[0023] In an embodiment in which the antenna unit 1 is used as an electromagnetic wave reflecting unit, by providing a second electrode 15 on the surface of the second substrate 11 on the signal SG side (for example, the outer surface S11-2), it is possible to shorten the signal transmission path and reduce the loss caused by the signal SG passing through the second substrate 11, which is advantageous for signal transmission.
[0024] The sidewall electrodes 16 are electrically insulated from one another and disposed on the sidewalls 12, respectively, and are electrically insulated from the first electrode 14 and the second electrode 15. In some embodiments, as shown in FIG. 3 , the antenna unit 1 may include four sidewall electrodes 16, such as a first sidewall electrode 16-1 disposed on the first sidewall 12-1, a second sidewall electrode 16-2 disposed on the second sidewall 12-2, a third sidewall electrode 16-3 disposed on the third sidewall 12-3, and a fourth sidewall electrode 16-4 disposed on the fourth sidewall 12-4. However, it should be understood that the number of sidewall electrodes 16 of the antenna unit 1 can be changed according to actual needs and is not limited to four. Depending on the design, the number of the sidewall electrodes 16 may be equal to or greater than the number of the sidewalls 12. For example, by increasing the number of sidewall electrodes 16 provided on any one of the sidewalls 12, the adjustment range of the horizontal electric field direction (electric field direction parallel to the XY plane) can be widened.
[0025] More specifically, since the sidewall electrodes 16 are electrically insulated from one another, it is possible to independently control the voltage applied to each sidewall electrode 16. By independently controlling the voltage applied to each sidewall electrode 16, it is possible to modulate the direction of the horizontal electric field applied to the liquid crystal layer 13, thereby adjusting the orientation of the liquid crystal molecules in the liquid crystal layer 13.
[0026] By applying a horizontal electric field to the liquid crystal layer 13 before modulating the electromagnetic wave (e.g., applying a vertical electric field), the orientation direction of multiple liquid crystal molecules in the liquid crystal layer 13 becomes parallel to the polarization direction of the signal SG (the polarization direction of the electric field of the electromagnetic wave), and the problem of double dielectric constant can be improved (e.g., the liquid crystal layer 13 provides the electromagnetic wave with a single dielectric constant), and the design parameters such as the transmission direction and radiation intensity of the signal modulated by the antenna unit 1 are set to fall within a predetermined range.
[0027] For example, another antenna unit (not shown, e.g., referred to as a second antenna unit) can be used to detect the electromagnetic wave and confirm the polarization direction of the electromagnetic wave. When the polarization direction of the signal SG (see FIG. 2) incident on the antenna unit 1 is parallel to the X direction, the liquid crystal molecules 130 in the liquid crystal layer 13 can be first aligned so that the long axes AL of the liquid crystal molecules 130 (e.g., positive liquid crystal molecules) in the liquid crystal layer 13 are parallel or approximately parallel to the X direction, as shown in FIGS.
[0028] The above-mentioned step of aligning the plurality of liquid crystal molecules 130 (applying a horizontal electric field) may include applying a first voltage to the first sidewall electrode 16-1 and applying a second voltage different from the first voltage to the third sidewall electrode 16-3 to generate a horizontal electric field parallel to the X direction. In some embodiments, the step of orienting (applying a horizontal electric field to) the plurality of liquid crystal molecules 130 may further include floating sidewall electrodes (such as the second sidewall electrode 16-2 and the fourth sidewall electrode 16-2) other than the first sidewall electrode 16-1 and the third sidewall electrode 16-3, or applying a third voltage between the first voltage and the second voltage to sidewall electrodes (such as the second sidewall electrode 16-2 and the fourth sidewall electrode 16-2) other than the first sidewall electrode 16-1 and the third sidewall electrode 16-3, so as to align the long axes AL of the plurality of liquid crystal molecules 130 in at least a central region (a main region for modulating electromagnetic waves, such as a region where the second electrode is located) of the antenna unit 1 parallel or approximately parallel to the polarization direction of the signal (such as the X direction).
[0029] After applying a horizontal electric field to the liquid crystal layer 13 to align the liquid crystal molecules 130 parallel to the polarization direction of the signal SG (see FIG. 2) incident on the antenna unit 1, a vertical electric field (an electric field parallel to the Z direction) is applied to the liquid crystal layer 13 using the first electrode 14 and the second electrode 15 to change the equivalent dielectric constant of the antenna unit 1, thereby modulating design parameters such as the signal transmission direction and / or radiation intensity. FIG. 5 shows the state of the liquid crystal layer 13 when the potential difference between the first electrode 14 and the second electrode 15 is zero, and FIGS. 6 to 7 show the states of the liquid crystal layer 13 when the potential difference between the first electrode 14 and the second electrode 15 is not zero. As shown in FIGS. 5 to 7, as the vertical electric field (the potential difference between the first electrode 14 and the second electrode 15) applied to the liquid crystal layer 13 gradually increases from zero, the long axes AL of the liquid crystal molecules 130 change from a direction parallel to the X direction to a direction between the X and Z directions. If the perpendicular electric field is large enough, the long axes AL of the liquid crystal molecules 130 may even become parallel to the Z direction.
[0030] The step of applying the vertical electric field may include applying a fourth voltage to the first electrode 14 and a fifth voltage, which may be the same as or different from the fourth voltage, to the second electrode 15. When the fourth voltage is the same as the fifth voltage, the potential difference between the first electrode 14 and the second electrode 15 is zero, and the liquid crystal layer 13 assumes a state shown in FIG. 5, for example. When the fourth voltage is different from the fifth voltage, the potential difference between the first electrode 14 and the second electrode 15 is not zero, and the liquid crystal layer 13 assumes a state shown in FIG. 6, for example. In some embodiments, when the fourth voltage is applied to the first electrode 14 and the fifth voltage is applied to the second electrode 15, the plurality of sidewall electrodes 16 (including the first sidewall electrode 16-1, the second sidewall electrode 16-2, the third sidewall electrode 16-3, and the fourth sidewall electrode 16-4) can be floating. With this structure, after floating the multiple sidewall electrodes 16 for a certain period of time, a horizontal electric field is again applied to the liquid crystal layer 13 to readjust the orientation of the multiple liquid crystal molecules 130, so that the orientation direction of the liquid crystal molecules 130 can be continuously made parallel to the set polarization direction, for example, parallel to the polarization direction of the signal SG (see Figure 2) incident on the antenna unit 1, but this is not limited to this.
[0031] Alternatively, in other embodiments, when a fourth voltage is applied to the first electrode 14 and a fifth voltage is applied to the second electrode 15, the fourth voltage may be applied to the first sidewall electrode 16-1 and the fifth voltage may be applied to the third sidewall electrode 16-3 to maintain the alignment direction or reduce the number or frequency of reorientations of the liquid crystal molecules 130. In some embodiments, to shorten the alignment time or improve the consistency of the alignment, the voltage difference between the first and second voltages used for alignment (e.g., the absolute value after subtracting the second voltage from the first voltage) may be greater than the voltage difference between the fourth and fifth voltages used to maintain the alignment (e.g., the absolute value after subtracting the fifth voltage from the fourth voltage), without being limited thereto.
[0032] Furthermore, when the polarization direction of the signal SG (see Figure 2) incident on the antenna unit 1 is parallel to the Y direction, the liquid crystal molecules 130 in the liquid crystal layer 13 may be aligned first, and the long axes AL of the liquid crystal molecules 130 (such as positive liquid crystal molecules) in the liquid crystal layer 13 may be aligned parallel or approximately parallel to the Y direction, as shown in Figures 8 and 9.
[0033] The above-mentioned step of orienting the plurality of liquid crystal molecules 130 (applying a horizontal electric field) may include applying a first voltage to the second sidewall electrode 16-2 and a second voltage to the fourth sidewall electrode 16-4 to generate a horizontal electric field parallel to the Y direction. In some embodiments, the step of orienting (applying a horizontal electric field to) the plurality of liquid crystal molecules 130 may further include floating the sidewall electrodes (such as the first sidewall electrode 16-1 and the third sidewall electrode 16-3) other than the second sidewall electrode 16-2 and the fourth sidewall electrode 16-2, or applying a third voltage between the first voltage and the second voltage to the sidewall electrodes (such as the first sidewall electrode 16-1 and the third sidewall electrode 16-3) other than the second sidewall electrode 16-2 and the fourth sidewall electrode 16-2, so as to align the long axes AL of the plurality of liquid crystal molecules 130 in at least a central region of the antenna unit 1 (a main region for modulating electromagnetic waves, such as the region where the second electrode is located) parallel or approximately parallel to the polarization direction of the signal (such as the Y direction).
[0034] After applying a horizontal electric field to the liquid crystal layer 13 to align the liquid crystal molecules 130 parallel to the polarization direction of the signal SG (see FIG. 2) incident on the antenna unit 1, a vertical electric field (electric field parallel to the Z direction) is applied to the liquid crystal layer 13 using the first electrode 14 and the second electrode 15 to change the equivalent dielectric constant of the antenna unit 1, thereby modulating design parameters such as the signal transmission direction and / or radiation intensity. FIG. 9 shows the state of the liquid crystal layer 13 when the potential difference between the first electrode 14 and the second electrode 15 is zero, and FIGS. 10 and 11 show the state of the liquid crystal layer 13 when the potential difference between the first electrode 14 and the second electrode 15 is not zero. As shown in FIGS. 9 to 11, as the vertical electric field (potential difference between the first electrode 14 and the second electrode 15) applied to the liquid crystal layer 13 gradually increases from zero, the long axes AL of the liquid crystal molecules 130 change from a direction parallel to the Y direction to a direction between the Y direction and the Z direction. If the perpendicular electric field is large enough, the long axes AL of the liquid crystal molecules 130 may even become parallel to the Z direction.
[0035] The step of applying the vertical electric field may include applying a fourth voltage to the first electrode 14 and a fifth voltage to the second electrode 15. When the fourth voltage is equal to the fifth voltage, the potential difference between the first electrode 14 and the second electrode 15 is zero, and the liquid crystal layer 13 assumes a state shown in FIG. 8, for example. When the fourth voltage is different from the fifth voltage, the potential difference between the first electrode 14 and the second electrode 15 is not zero, and the liquid crystal layer 13 assumes a state shown in FIG. 9, for example. In some embodiments, when the fourth voltage is applied to the first electrode 14 and the fifth voltage is applied to the second electrode 15, the plurality of sidewall electrodes 16 (including the first sidewall electrode 16-1, the second sidewall electrode 16-2, the third sidewall electrode 16-3, and the fourth sidewall electrode 16-4) can be floating. With this structure, after floating the multiple sidewall electrodes 16 for a certain period of time, a horizontal electric field is again applied to the liquid crystal layer 13 to readjust the orientation of the multiple liquid crystal molecules 130, so that the orientation direction of the liquid crystal molecules 130 can be continuously made parallel to the set polarization direction, for example, parallel to the polarization direction of the signal SG (see Figure 2) incident on the antenna unit 1, but this is not limited to this.
[0036] Alternatively, in other embodiments, when a fourth voltage is applied to the first electrode 14 and a fifth voltage is applied to the second electrode 15, a fourth voltage may be applied to the second sidewall electrode 16-2 and a fifth voltage may be applied to the fourth sidewall electrode 16-2 to maintain the alignment direction or reduce the number or frequency of reorientations of the liquid crystal molecules 130. In some embodiments, to shorten the alignment time or improve the consistency of the alignment, the voltage difference between the first and second voltages used for alignment (e.g., the absolute value after subtracting the second voltage from the first voltage) may be greater than the voltage difference between the fourth and fifth voltages used to maintain the alignment (e.g., the absolute value after subtracting the fifth voltage from the fourth voltage), but is not limited to this.
[0037] Furthermore, when the polarization direction of the signal SG (see FIG. 2) incident on the antenna unit 1 is parallel to the D direction, and the D direction is non-parallel and non-perpendicular to the X direction and the Y direction, the liquid crystal molecules 130 in the liquid crystal layer 13 are first aligned, and the long axes AL of the liquid crystal molecules 130 (e.g., positive liquid crystal molecules) in the central region of the liquid crystal layer 13 can be aligned parallel or approximately parallel to the D direction, as shown in FIG. 12.
[0038] The above-mentioned process of aligning the plurality of liquid crystal molecules 130 (applying a horizontal electric field) may include applying a first voltage to the first sidewall electrode 16-1 and the second sidewall electrode 16-2, and applying a second voltage to the third sidewall electrode 16-3 and the fourth sidewall electrode 16-2, to generate a horizontal electric field substantially parallel to the D direction in the central region of the liquid crystal layer 13.
[0039] As described above, a horizontal electric field is applied to the liquid crystal layer 13 to align the orientation direction of the liquid crystal molecules 130 parallel to the polarization direction of the signal SG (see Figure 2) incident on the antenna unit 1, and then a vertical electric field (an electric field parallel to the Z direction) is applied to the liquid crystal layer 13 using the first electrode 14 and the second electrode 15, thereby changing the equivalent dielectric constant of the antenna unit 1 and modulating design parameters such as the phase delay and / or radiation intensity of the signal SG (such as electromagnetic waves).
[0040] The above-mentioned step of applying a vertical electric field may include applying a fourth voltage to the first electrode 14 and a fifth voltage to the second electrode 15. In some embodiments, when the fourth voltage is applied to the first electrode 14 and the fifth voltage is applied to the second electrode 15, the sidewall electrodes 16 (including the first sidewall electrode 16-1, the second sidewall electrode 16-2, the third sidewall electrode 16-3, and the fourth sidewall electrode 16-4) may be floated. In this structure, after the sidewall electrodes 16 are floated for a certain period of time, a horizontal electric field may be applied to the liquid crystal layer 13 again to readjust the alignment of the liquid crystal molecules 130 so that the alignment direction of the liquid crystal molecules 130 remains parallel to the set polarization direction, for example, but not limited to, parallel to the polarization direction of the signal SG (see FIG. 2 ) incident on the antenna unit 1.
[0041] Alternatively, in other embodiments, when a fourth voltage is applied to the first electrode 14 and a fifth voltage is applied to the second electrode 15, the fourth voltage may be applied to the first sidewall electrode 16-1 and the second sidewall electrode 16-2, and the fifth voltage may be applied to the third sidewall electrode 16-3 and the fourth sidewall electrode 16-4 to maintain the alignment direction or reduce the number or frequency of reorientations of the liquid crystal molecules 130. In some embodiments, to shorten the alignment time or improve the consistency of the alignment, the voltage difference between the first and second voltages used for alignment (e.g., the absolute value after subtracting the second voltage from the first voltage) may be greater than the voltage difference between the fourth and fifth voltages used to maintain the alignment (e.g., the absolute value after subtracting the fifth voltage from the fourth voltage), but is not limited to this.
[0042] In the above embodiment, an example has been described in which one sidewall electrode 16 is provided on each sidewall 12, but the present invention is not limited to this. As shown in Fig. 13, in the antenna unit 1A, multiple sidewall electrodes 16 may be provided on each sidewall 12. For example, a first sidewall electrode 16-1 and a second sidewall electrode 16-2 may be provided on the first sidewall 12-1, a third sidewall electrode 16-3 and a fourth sidewall electrode 16-4 may be provided on the second sidewall 12-2, a fifth sidewall electrode 16-5 and a sixth sidewall electrode 16-6 may be provided on the third sidewall 12-3, and a seventh sidewall electrode 16-7 and an eighth sidewall electrode 16-8 may be provided on the fourth sidewall 12-4, but the present invention is not limited to this. Increasing the number of sidewall electrodes 16 can increase the adjustment range of the horizontal electric field direction (electric field direction parallel to the XY plane), that is, the adjustment range / angle of the alignment direction of the liquid crystal layer 13. For example, in some embodiments, a first voltage, a second voltage, a third voltage, a fourth voltage, a fifth voltage, and a sixth voltage may be applied to the eighth sidewall electrode 16-8, the fourth sidewall electrode 16-4, the first sidewall electrode 16-1, the third sidewall electrode 16-3, the seventh sidewall electrode 16-7, and the fifth sidewall electrode 16-5, respectively, and the second sidewall electrode 16-2 and the sixth sidewall electrode 16-6 may be floating. Here, the voltage difference between the first voltage and the second voltage (e.g., the second voltage minus the first voltage) is greater than the voltage difference between the third voltage and the fourth voltage (e.g., the fourth voltage minus the third voltage), and the voltage difference between the third voltage and the fourth voltage is equal to the voltage difference between the fifth voltage and the sixth voltage (e.g., the sixth voltage minus the fifth voltage), but is not limited to this. In other embodiments, a first voltage may be applied to the first sidewall electrode 16-1 and the eighth sidewall electrode 16-8, a second voltage may be applied to the fourth sidewall electrode 16-4 and the fifth sidewall electrode 16-5, a third voltage may be applied to the third sidewall electrode 16-3 and the sixth sidewall electrode 16-6, and a fourth voltage may be applied to the second sidewall electrode 16-2 and the seventh sidewall electrode 16-7. Here, the second voltage is greater than the third voltage, the third voltage is greater than the fourth voltage, and the fourth voltage is greater than the first voltage.
[0043] 14 and 15, the antenna array AR may include, but is not limited to, a plurality of first antenna units U1 and at least one second antenna unit U2, and may further include other components or film layers as needed.
[0044] The first antenna unit U1 is used to modulate design parameters such as the transmission direction and / or radiation intensity of a signal (such as an electromagnetic wave). Each of the multiple first antenna units U1 can adopt the structure of the antenna unit 1 or antenna unit 1A described above, which will not be repeated here.
[0045] At least one second antenna unit U2 is disposed adjacent to the plurality of first antenna units U1. Fig. 12 shows a schematic diagram of the second antenna unit U2, which is disposed on one side of the plurality of first antenna units U1. However, it should be understood that the number of second antenna units U2 in the antenna array AR may be plural, and the actual structure of the plurality of second antenna units U2 and their relative installation relationship with the plurality of first antenna units U1 may be changed according to actual needs.
[0046] The second antenna unit U2 is used, for example, to detect electromagnetic waves transmitted to the antenna array AR and confirm the polarization direction of the electromagnetic waves, and the orientation direction of the liquid crystal layer 13 in each first antenna unit U1 can be controlled as needed (by blocking or reflecting the electromagnetic waves, etc.).
[0047] The configuration of the second antenna unit U2 may be different from the configuration of the first antenna unit U1. As shown in Fig. 15, the second antenna unit U2 may include a third electrode 17 and a fourth electrode 18, which may be provided on at least one of the first substrate 10 and the second substrate 11. Fig. 15 schematically illustrates that the third electrode 17 and the fourth electrode 18 are provided on the inner surface S11-1 and the outer surface S11-2 of the second substrate 11, respectively, that is, the distance DT between the third electrode 17 and the fourth electrode 18 is equal to the thickness T11 of the second substrate 11. However, it should be understood that the third electrode 17 and the fourth electrode 18 may be provided on the outer surface S10-2 and the inner surface S10-1 of the first substrate 10, respectively, i.e., the distance DT between the third electrode 17 and the fourth electrode 18 may be equal to the thickness T10 of the first substrate 10. Alternatively, the third electrode 17 and the fourth electrode 18 may be provided on the first substrate 10 and the second substrate 11, respectively.
[0048] 15, the first electrodes 14 in the first antenna units U1 are separated from each other, but the present invention is not limited to this. As shown in FIG. 16, the first electrodes 14 in the first antenna units U1 may be connected to each other.
[0049] 15 and 16, two adjacent first antenna units U1 share, for example, a side wall 12, but the present invention is not limited to this. As shown in Fig. 17, two adjacent first antenna units U1 do not need to share a side wall 12. For example, the two adjacent side walls 12 of two adjacent first antenna units U1 may be separated from each other, and the gap G between the two adjacent side walls 12 may be filled with a liquid crystal layer 13 or may not be filled with any material.
[0050] 15 to 17, the third electrode 17 and the fourth electrode 18 are respectively provided on the inner surface S11-1 and the outer surface S11-2 of the second substrate 11, but the present invention is not limited thereto. As shown in FIG. 18, the third electrode 17 and the fourth electrode 18 may be respectively provided on the first substrate 10 and the second substrate 11. For example, the third electrode 17 may be disposed on the inner surface S10-1 of the first substrate 10, and the fourth electrode 18 may be disposed on the outer surface S11-2 of the second substrate 11. In this structure, the second antenna unit U2 may further include a solid dielectric layer 19 disposed between the first substrate 10 and the second substrate 11. For appearance considerations, the dielectric constant of the solid dielectric layer 19 may be close to that of the liquid crystal layer 13. Also, the material of the solid dielectric layer 19 can be selected from fiberglass cloth (such as FR4), high frequency PCB material for antenna (such as Rogers), low temperature co-fired ceramics (LTCC) or other similar and suitable for high frequency signal dielectric materials.
[0051] 19, the plurality of first antenna units U1 can be divided into a plurality of groups, and the antenna units of different groups can be used to transmit and receive signals with different polarization directions. For example, the plurality of first antenna units U1 can be divided into a first group of antenna units G1 and a second group of antenna units G2, and the first group of antenna units G1 can be used to transmit and receive signals with a first polarization direction, and the second group of antenna units G2 can be used to transmit and receive signals with a second polarization direction.
[0052] In some embodiments, as shown in FIG. 20, the antenna array AR may include a plurality of second antenna units U2, which may be distributed among a plurality of first antenna units U1.
[0053] In summary, in the embodiment of the present invention, by providing a plurality of sidewall electrodes, the alignment of the liquid crystal layer can be adjusted according to the polarization direction of the signal, which contributes to improving the problem of double dielectric constant.
[0054] Although the present invention has been disclosed through the above embodiments, they are not intended to limit the present invention, and a person having ordinary skill in the relevant technical field can make some modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application. [Industrial Applicability]
[0055] The present invention provides an antenna unit, an antenna array and a method for operating the antenna array, which can adjust the orientation of a liquid crystal layer. [Explanation of symbols]
[0056] 1, 1A: Antenna unit 10: First substrate 11: Second board 12: Side wall 12-1: First side wall 12-2: Second side wall 12-3: Third side wall 12-4: Fourth side wall 13: Liquid crystal layer 14: First electrode 15: Second electrode 16: Side wall electrode 16-1: First sidewall electrode 16-2: Second sidewall electrode 16-3: Third sidewall electrode 16-4: Fourth sidewall electrode 16-5: Fifth sidewall electrode 16-6: Sixth sidewall electrode 16-7: Seventh sidewall electrode 16-8: Eighth sidewall electrode 17: Third electrode 18: Fourth electrode 19: Solid dielectric layer 130: Liquid crystal molecules S10-1, S11-1: Inner surface S10-2, S11-2: Outer surface AL:Long axis AR: Antenna Array D, X, Y, Z: Direction DT: distance G: Gap G1: First group antenna unit G2: Second group antenna unit R1, R2: Cross section SG:Signal T10, T11: Thickness U1: First antenna unit U2: Second antenna unit I-I': Cutting line
Claims
1. 1. An antenna array comprising: a plurality of first antenna units; Each of the plurality of first antenna units comprises: a first substrate; a second substrate facing the first substrate; a plurality of side walls supporting the first substrate and the second substrate; a liquid crystal layer located between the first substrate, the second substrate, and the plurality of side walls; a first electrode provided on the first substrate; a second electrode provided on the second substrate and electrically insulated from the first electrode; a plurality of sidewall electrodes provided on the plurality of sidewalls and electrically insulated from each other, the sidewall electrodes being electrically insulated from the first electrode and the second electrode; The antenna array further comprises: a third electrode and a fourth electrode provided adjacent to the plurality of first antenna units, the third electrode and the fourth electrode including at least one second antenna unit provided on at least one of the first substrate and the second substrate; a distance between the third electrode and the fourth electrode is equal to a thickness of the first substrate or a thickness of the second substrate; Antenna array.
2. An antenna array, a plurality of first antenna units; Each of the plurality of first antenna units comprises: a first substrate; a second substrate facing the first substrate; a plurality of side walls supporting the first substrate and the second substrate; a liquid crystal layer located between the first substrate, the second substrate, and the plurality of side walls; a first electrode provided on the first substrate; a second electrode provided on the second substrate and electrically insulated from the first electrode; a plurality of sidewall electrodes provided on the plurality of sidewalls and electrically insulated from each other, the sidewall electrodes being electrically insulated from the first electrode and the second electrode; The antenna array further comprises: a third electrode and a fourth electrode provided adjacent to the plurality of first antenna units, the third electrode and the fourth electrode including at least one second antenna unit provided on at least one of the first substrate and the second substrate; the third electrode and the fourth electrode are provided on the first substrate and the second substrate, respectively, and the at least one second antenna unit further includes a solid dielectric layer provided between the first substrate and the second substrate. Antenna array.
3. the second substrate is located between the second electrode and the liquid crystal layer; 3. An antenna array according to claim 1 or 2.
4. the number of the sidewall electrodes is equal to or greater than the number of the sidewalls; 3. An antenna array according to claim 1 or 2.
5. 1. A method of operating an antenna array, comprising: providing an antenna array including a plurality of first antenna units; Each of the plurality of first antenna units comprises: a first substrate; a second substrate facing the first substrate; a plurality of side walls supporting the first substrate and the second substrate; a liquid crystal layer positioned between the first substrate, the second substrate, and the plurality of sidewalls; a first electrode provided on the first substrate; a second electrode provided on the second substrate and electrically insulated from the first electrode; a plurality of sidewall electrodes provided on the plurality of sidewalls and electrically insulated from each other, the sidewall electrodes being electrically insulated from the first electrode and the second electrode; Including, The method of operating the antenna array may further include: applying a horizontal electric field parallel to an XY plane to the liquid crystal layer using the plurality of sidewall electrodes; applying a vertical electric field to the liquid crystal layer using the first electrode and the second electrode; Including, Applying the horizontal electric field applying a first voltage to at least one sidewall electrode of the plurality of sidewall electrodes and a second voltage different from the first voltage to at least another sidewall electrode of the plurality of sidewall electrodes; floating the sidewall electrodes other than the at least one sidewall electrode and the at least another sidewall electrode, or applying a third voltage between the first voltage and the second voltage to the sidewall electrodes other than the at least one sidewall electrode and the at least another sidewall electrode; A method of operating an antenna array, including:
6. the horizontal electric field is applied before the vertical electric field is applied; 6. A method of operating an antenna array according to claim 5.
7. applying the perpendicular electric field applying a fourth voltage to the first electrode and a fifth voltage different from the fourth voltage to the second electrode.
6. A method of operating an antenna array according to claim 5.
8. when the fourth voltage is applied to the first electrode and the fifth voltage is applied to the second electrode, the sidewall electrodes are made floating; 8. The method of operating an antenna array according to claim 7, further comprising:
9. After floating the sidewall electrodes for a certain period of time, the horizontal electric field is again applied to the liquid crystal layer to readjust the orientation of the liquid crystal molecules; 9. The method of operating an antenna array according to claim 8, further comprising:
10. applying the fourth voltage to the at least one sidewall electrode and the fifth voltage to the at least another sidewall electrode when applying the fourth voltage to the first electrode and the fifth voltage to the second electrode; 8. The method of operating an antenna array according to claim 7, further comprising:
11. a voltage difference between the first voltage and the second voltage is greater than a voltage difference between the fourth voltage and the fifth voltage; 11. A method of operating an antenna array according to claim 10.
12. The antenna array further includes at least one second antenna unit, and a method of operating the antenna array includes: using the at least one second antenna unit to detect the electromagnetic waves transmitted to the antenna array to ascertain the polarization direction of the electromagnetic waves; 6. The method of operating an antenna array according to claim 5, further comprising:
Citation Information
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