Beam pointing adjustment structure and adjustment method, scanning device

Abstract

The present application relates to a kind of beam pointing adjustment structures, including first electrode layer and second electrode layer, super surface functional structure is arranged between first electrode layer and second electrode layer;First electrode layer includes at least one row of periodically arranged multiple block electrodes, second electrode layer is surface electrode, or includes with the block electrode of first electrode layer one-to-one corresponding block electrode;Super surface functional structure includes dielectric elastomer, multiple functional units embedded in dielectric elastomer, multiple functional units are set up one by one with multiple block electrodes, each functional unit includes periodically arranged multiple sub-functional units;Further include control structure, for using holographic principle, according to the pointing of required target wave, corresponding block electrode in first electrode layer and second electrode layer are applied voltage, so that dielectric elastomer and corresponding area deformation, to change the arrangement period of multiple sub-functional units in corresponding functional unit.The present application also relates to scanning device and beam pointing adjustment method.

Description

Technical Field

[0001] This invention relates to the field of holographic technology, and in particular to a beam pointing adjustment structure and method, and a scanning device. Background Technology

[0002] Beam control has been widely applied in radar technology, while recent advancements in optical detection and ranging technologies have built upon previous radar technologies. Traditional LiDAR technology uses a laser source to illuminate a target object and calculates the object's distance by detecting the return time (time of flight) of the reflected light pulse. This technology is already used in ground-based, aircraft, and space devices for environmental perception. Ground-based LiDAR technology, initially used for simple measurements (distance or vehicle speed), is now widely used in various advanced devices, such as autonomous driving and AI robots. Consumer electronics applications include iPhones, iPads, Microsoft's indoor motion capture sensors, and AR / VR displays.

[0003] Currently, several LiDAR systems have been optimized to meet the requirements of various applications. For example, while cost and size are important for consumer electronics, measurement accuracy, measurable range, and system stability are also crucial for precision devices. Considering the real-world applications and potential economic impact of LiDAR, research and development in both hardware and software are expected to experience rapid growth, even in the near future.

[0004] For certain specialized applications, the decision time of LiDAR systems for autonomous vehicles needs to be fast enough to ensure safe stopping in dangerous situations. Specifically, for personal safety, it is essential to meet requirements such as safe measurement distance, high accuracy, a 360° real-time operating range, and an optical system capable of withstanding adverse weather conditions and maintaining stable operation under varying sunlight conditions. Based on these requirements, it is desirable for LiDAR systems to be manufactured as compact and affordable chip-scale sensors. However, currently, no commercially available LiDAR system meets these requirements. The vast majority of commercially available LiDAR systems are primarily based on MEMS systems, which are bulky and susceptible to environmental influences. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a beam pointing adjustment structure and method, as well as a scanning device, which solves the problems of non-adjustable beam pointing and susceptibility to environmental influences.

[0006] To achieve the above objectives, the technical solution adopted in this embodiment of the invention is: a beam pointing adjustment structure, characterized in that it includes a first electrode layer and a second electrode layer disposed opposite to each other, and a metasurface functional structure disposed between the first electrode layer and the second electrode layer;

[0007] The first electrode layer includes at least one row of periodically arranged block electrodes, and the second electrode layer is a planar electrode, or the second electrode layer includes a plurality of block electrodes that correspond one-to-one with the block electrodes in the first electrode layer.

[0008] The metasurface functional structure includes a dielectric elastomer and multiple functional units embedded in the dielectric elastomer. The multiple functional units are arranged in a one-to-one correspondence with the multiple block electrodes. Each functional unit includes multiple sub-functional units arranged periodically.

[0009] The beam pointing adjustment structure also includes a control structure for applying voltage to the corresponding block electrode and the second electrode layer in the first electrode layer according to the direction of the desired target wave using the holographic principle, so that the dielectric elastomer and the region corresponding to the corresponding block electrode deform, thereby changing the arrangement period of the plurality of sub-functional units in the functional unit corresponding to the corresponding block electrode.

[0010] Optionally, a voltage is applied to the corresponding block electrode in the first electrode layer and the second electrode layer, thereby increasing the arrangement period of the plurality of sub-functional units in the functional unit corresponding to the block electrode.

[0011] Optionally, the control structure includes:

[0012] The target wave function expression acquisition unit is used to obtain the function expression of the target wave in free space based on the beam azimuth angle Φ and elevation angle θ of the desired target wave.

[0013] The interference wave function expression acquisition unit is used to obtain the expression of the known reference wave A. ref =e -ikz

[0014] Based on the principle of holography, the expression for the interference wave formed by the reference wave and the target wave is obtained:

[0015]

[0016] Based on the above formula (1), the following formula is obtained by taking the real part using Euler's formula:

[0017]

[0018] The control signal generation unit is used to obtain the two-dimensional coordinates (x, y, y) according to the formula (2). i y i The result corresponding to the functional unit of the function is compared with a preset threshold using a binary method, and a voltage signal is generated when the result is greater than the preset threshold, wherein the preset threshold is less than 1 and greater than zero.

[0019] An execution unit is configured to apply voltage to the corresponding block electrode in the first electrode layer and the second electrode layer according to the signal issued by the control signal generation unit.

[0020] Optionally, the sub-functional unit includes a surface plasmon, which includes a substrate layer, a dielectric layer, and a metal layer stacked sequentially along a first direction, where the first direction is the incident direction of the reference wave onto the metasurface functional structure.

[0021] Optionally, the dielectric layer is made of SiN. x The metal layer is made of Al, Ag, or Au.

[0022] Optionally, the substrate layer is made of Al2O3.

[0023] This invention also provides a scanning device, including the beam pointing adjustment structure described above.

[0024] This invention also provides a beam pointing adjustment method, which uses the above-described beam pointing adjustment structure for adjustment, and includes the following steps:

[0025] The functional expression of the target wave in free space is obtained based on the beam azimuth angle Φ and elevation angle θ of the desired target wave.

[0026] Based on the known expression for the reference wave, Aref = e^(-ikz), and the holographic principle, the expression for the interference wave formed by the reference wave and the target wave is obtained:

[0027]

[0028] Based on the above formula (1), the following formula is obtained by taking the real part using Euler's formula:

[0029]

[0030] According to the formula (2), the two-dimensional coordinates are obtained as (x i y iThe result corresponding to the functional unit of ) is compared with a preset threshold using a binary method, and a voltage application signal is generated when the result is greater than the preset threshold, wherein the preset threshold is less than 1 and greater than zero;

[0031] Based on the received signal of applied voltage, voltage is applied to the corresponding block electrode and the second electrode layer in the first electrode layer, thereby increasing the arrangement period of the sub-functional units in the corresponding functional unit.

[0032] Optionally, the preset threshold is 0.5.

[0033] Optionally, based on the received signal of the applied voltage, an insertion voltage of 15-30V is applied to the corresponding block electrode in the first electrode layer and the second electrode layer.

[0034] The beneficial effects of this invention are: based on the principle of holography, the beam direction can be easily adjusted, avoiding environmental influences. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the beam pointing adjustment structure in an embodiment of the present invention;

[0036] Figure 2 A schematic diagram showing the structure of sub-functional units within a functional unit. Figure 1 ;

[0037] Figure 3 A schematic diagram showing the structure of sub-functional units within a functional unit. Figure 2 ;

[0038] Figure 4 express Figure 3 A schematic diagram of light transmittance at the location of the central functional unit;

[0039] Figure 5 express Figure 3 The diagram shows the state of the functional units shown.

[0040] Figure 6 A schematic diagram showing the distribution of sub-functional units of a functional unit after voltage is applied;

[0041] Figure 7 express Figure 6 A schematic diagram of light transmittance at the location of the central functional unit;

[0042] Figure 8 express Figure 6 The diagram shows the state of the functional units shown.

[0043] Figure 9 A schematic diagram illustrating amplitude modulation, representing the principle of holography;

[0044] Figure 10 A simulation diagram showing the target table angle as -30 degrees;

[0045] Figure 11 A simulation diagram showing the target table angle as 0 degrees;

[0046] Figure 12 A simulation diagram showing the target table angle of 30 degrees;

[0047] Figure 13 A partial schematic diagram showing the beam pointing adjustment structure;

[0048] Figure 14 A schematic diagram showing the process of depositing GeO2 on a substrate;

[0049] Figure 15 A schematic diagram showing spin-coated photoresist and patterning;

[0050] Figure 16 A schematic diagram showing the deposition of AL2O3;

[0051] Figure 17 A schematic diagram showing the deposition of SiNx;

[0052] Figure 18 A schematic diagram showing the Al vapor deposition process;

[0053] Figure 19 This is a schematic diagram showing the functional units after they have been formed.

[0054] Figure 20 A schematic diagram illustrating a water bath;

[0055] Figure 21 A schematic diagram illustrating the formation of metasurface functional structures. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0057] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0058] like Figures 1-13 As shown, this embodiment provides a beam pointing adjustment structure, characterized in that it includes a first electrode layer 1 and a second electrode layer 2 disposed opposite to each other, and a metasurface functional structure disposed between the first electrode layer 1 and the second electrode layer 2.

[0059] The first electrode layer 1 includes at least one row of periodically arranged block electrodes, and the second electrode layer 2 is a planar electrode, or the second electrode layer 2 includes block electrodes that correspond one-to-one with the block electrodes in the first electrode layer 1.

[0060] The metasurface functional structure includes a dielectric elastomer 3 and a plurality of functional units 4 embedded in the dielectric elastomer 3. The plurality of functional units 4 are arranged in a one-to-one correspondence with the plurality of block electrodes. Each functional unit 4 includes a plurality of sub-functional units 5 arranged periodically.

[0061] The beam pointing adjustment structure also includes a control structure, which uses the holographic principle to apply voltage to the corresponding block electrode in the first electrode layer 1 and the second electrode layer 2 according to the direction of the desired target wave, so that the dielectric elastomer 3 and the region corresponding to the corresponding block electrode undergo compression deformation, thereby changing the arrangement period of the plurality of sub-functional units 5 in the functional unit 4 corresponding to the corresponding block electrode.

[0062] The holographic principle originates from the field of optics and refers to the technique of using certain photosensitive materials to record the interference field formed by the interference of a reference wave and a target wave to obtain an interference surface, and then using the reference wave to illuminate the interference surface to invert and obtain the target wave. This embodiment utilizes the holographic principle to obtain the structural state of the corresponding functional unit by inversely calculating the direction of the desired target wave, thereby achieving adjustable direction of the target wave.

[0063] In order to achieve adjustable target wave direction, the state of each functional unit 4 needs to be independently controlled. This means that the arrangement period of multiple sub-functional units 5 of one functional unit 4 can be changed individually, or the arrangement period of multiple sub-functional units 5 of at least two functional units 4 can be changed, dividing at least one electrode layer of the first electrode layer 1 and the second electrode layer 2 into multiple block electrodes arranged in at least one row periodically.

[0064] For example, the first electrode layer 1 includes at least one row of periodically arranged block electrodes, and the second electrode layer 2 is a planar electrode, as shown in the reference. Figure 1 .

[0065] When a voltage is applied, a voltage is applied to a plurality of block electrodes and planar electrodes, causing the dielectric elastomer 3 to be compressed and deformed in a first portion between the plurality of block electrodes and planar electrodes, thereby changing the arrangement period of the plurality of sub-functional units 5 of the functional unit 4 located in the first portion.

[0066] For example, the first electrode layer 1 includes at least one row of periodically arranged block electrodes, and the second electrode layer 2 includes block electrodes that correspond one-to-one with the block electrodes in the first electrode layer 1. That is, the first electrode layer 1 has a first block electrode, and the second electrode layer 2 has a second block electrode that corresponds to the first block electrode. The projection of the first block electrode on the second electrode layer coincides with the second block electrode.

[0067] When a voltage is applied, a voltage is applied to the first block electrode and the second block electrode so that the first portion of the dielectric elastomer 3 located between the first block electrode and the second block electrode is compressed and deformed, thereby changing the arrangement period of the plurality of sub-functional units 5 of the functional unit 4 located in the first portion.

[0068] For example, the first electrode layer 1 includes a plurality of block electrodes arranged in a row periodically, or it may include a plurality of block electrodes distributed in a matrix, and the second electrode layer 2 is disposed correspondingly to the first electrode layer 1. Figure 1 and Figure 9 The diagram shown is a schematic representation of the first electrode layer 1 comprising a plurality of block electrodes arranged in a periodic row. Figure 13 It only represents one functional unit extending in the x-direction, and eight functional units arranged in the y-direction. Figure 13 This is a partial illustration and is not intended to be limited to this.

[0069] It should be noted that by applying voltage to the corresponding block electrode and the second electrode layer 2 in the first electrode layer 1, the dielectric elastomer 3 undergoes compression deformation in the region corresponding to the block electrode, thereby changing the arrangement period of the plurality of sub-functional units 5 in the functional unit 4 corresponding to the block electrode. This change in the arrangement period of the plurality of sub-functional units 5 can be increased or decreased, depending on the direction of the target wave and the required transmittance of the light wave at the corresponding position. In this embodiment, for example, voltage is applied to the corresponding block electrode and the second electrode layer 2 in the first electrode layer 1, causing the dielectric elastomer 3 to undergo compression deformation in the region corresponding to the block electrode, thereby increasing the arrangement period of the plurality of sub-functional units 5 in the functional unit 4 corresponding to the block electrode. This increases the light transmittance of the corresponding functional unit 4 by at least three times, facilitating the adjustment of the target wave direction.

[0070] In this embodiment, the sub-functional unit 5, by way of example, includes a surface plasmon, which comprises a base layer 51, a dielectric layer 52, and a metal layer 53 stacked sequentially along a first direction. The first direction is the incident direction of a reference wave onto the metasurface functional structure. Figure 2 .

[0071] The surface plasmon allows the reference wave to be incident on the beam pointing adjustment structure along the first direction (Z-axis direction). A surface plasmon polariton effect occurs on the side of the metal layer away from the dielectric layer, forming a surface wave. The reference wave interferes with the target wave. Amplitude sampling is performed using the interference wave function to obtain a cosine function based on the position coordinates of the functional unit 4. Binary sampling is then used to obtain the amplitude value (i.e., light transmittance) at the position of the functional unit 4. When the amplitude is less than a preset threshold, the state of the corresponding functional unit 4 is set to 0; when the amplitude is greater than the preset threshold, the state of the corresponding functional unit 4 is set to 1. This applies a voltage to the block electrode of the first electrode layer and the second electrode layer corresponding to the functional unit 4, increasing the arrangement period of the multiple sub-functional units 5 of the functional unit 4, thereby increasing the light transmittance at the position of the functional unit 4, thus reconstructing the target wave (i.e., adjusting its pointing). Figures 3-9 .

[0072] In this embodiment, the dielectric layer is exemplarily made of SiN. x The metal layer is made of a high-conductivity material such as Al, Ag, or Au.

[0073] In this embodiment, the substrate layer is made of Al2O3, which ensures that the substrate layer has high light transmittance.

[0074] In this embodiment, the control structure, as exemplified, includes:

[0075] The target wave function expression acquisition unit is used to obtain the function expression of the target wave in free space based on the beam azimuth angle Φ and elevation angle θ of the desired target wave.

[0076] The interference wave function expression acquisition unit is used to obtain the expression of the known reference wave A. ref =e -ikz

[0077] Based on the principle of holography, the expression for the interference wave formed by the reference wave and the target wave is obtained:

[0078]

[0079] Based on the above formula (1), the following formula is obtained by taking the real part using Euler's formula:

[0080] refer to Figure 9 ;

[0081] The control signal generation unit is used to obtain the two-dimensional coordinates (x, y, y) according to the formula (2). i y i The result corresponding to the functional unit 4 of the ) is compared with a preset threshold using a binary method, and a voltage signal is generated when the result is greater than the preset threshold, wherein the preset threshold is less than 1 and greater than zero;

[0082] An execution unit is configured to apply voltage to the corresponding block electrode in the first electrode layer 1 and the second electrode layer 2 according to the signal issued by the control signal generation unit.

[0083] The position coordinates (x) of the functional unit 4 i y i Substituting into formula (2), the result corresponding to the position of functional unit 4 is obtained. The result of the cosine function is between [0,1]. A preset threshold (e.g., 0.5) is set between [0,1], and the binary method is used to convert the position coordinates (x,y) of functional unit 4 into the result. i y iThe obtained result is compared with the preset threshold. When the result is greater than the preset threshold, the state of the functional unit is set to 1. When the result is less than the preset threshold, the state of the functional unit is set to 0. By continuously sampling the 0 and 1, voltage is applied to the block electrode of the first electrode layer 1 and the second electrode layer 2 corresponding to the position of the functional unit set to 1, so as to increase the arrangement period of the multiple sub-functional units 5 of the functional unit 4, thereby increasing the light transmittance at the position of the functional unit 4, so as to achieve the beam pointing angle of the target wave as θ.

[0084] In one specific embodiment, the first electrode layer 1 includes a row of block electrodes, and in the row direction, the first electrode layer 1 includes 96 block electrodes. When the angle of the target wave is -30 degrees, the state of the functional unit corresponding to the first 20 block electrodes from left to right is: 0 1 0 0 1 1 0 1 1 0 0 1 0 0 1 0 0 1 1 0 (-30°). See the simulation diagram for reference. Figure 10 When the target wave angle is 0 degrees, the state of the functional units corresponding to the first 20 block electrodes from left to right is: 01 1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 (0°). See the simulation diagram for reference. Figure 11 When the target wave angle is 30 degrees, the state of the functional units corresponding to the first 20 block electrodes from left to right is: 0 1 1 0 0 1 1 0 0 1 1 0 01 1 0 0 1 1 0 (30°). See the simulation diagram for reference. Figure 12 .

[0085] It should be noted that for functional unit 4 in state 1, when a voltage is applied to the corresponding electrode, the dielectric elastomer 3 and the part corresponding to the functional unit 4 deform, and the arrangement period of the multiple sub-functional units 5 of the functional unit 4 increases. The light transmission intensity at different positions of functional unit 4 is tuned by the arrangement period of the multiple sub-functional units 5 of the functional unit 4 at that position. The larger the arrangement period, the higher the transmittance.

[0086] In one specific embodiment, the reference wave is a light wave in the visible light range of 0.45-0.7 μm. When no voltage is applied, the arrangement period of the multiple sub-functional units 5 in the corresponding functional unit 4 is 100 nm. The transmittance obtained according to the above formula is 0.15, which, in the holographic amplitude modulation principle, indicates that light cannot pass through; this state is 0. Figure 3 This diagram illustrates the distribution of sub-functional units within a functional unit without applied voltage. Figure 4 A schematic diagram showing light transmittance. Figure 5This diagram illustrates the state of a functional unit. When a voltage is applied, the arrangement period of multiple sub-functional units within the corresponding functional unit increases to 300nm, and the transmittance increases to 0.75. In the principle of holographic amplitude modulation, this indicates that light can pass through; this state is represented by 1. Figure 6 This diagram illustrates the distribution of sub-functional units within a functional unit that applies voltage. Figure 6 and Figure 3 In contrast, after applying voltage, the distribution period of the sub-functional unit increases. Figure 7 A schematic diagram showing light transmittance. Figure 7 and Figure 4 In contrast, after applying voltage, the light transmittance increases. Figure 8 A schematic diagram showing the state of a functional unit. Figure 8 and Figure 5 In contrast, the functional unit state is 0 before the voltage is applied and 1 after the voltage is applied. By adjusting the voltage, the functional unit 4 can be dynamically adjusted, thereby making the direction of the target wave adjustable.

[0087] The fabrication process of the metasurface functional structure in this embodiment is as follows, refer to... Figures 14-21 :

[0088] A sacrificial layer 102 is formed by electron beam evaporation of GeO2 on a Si substrate 101;

[0089] Photoresist is spin-coated onto the sacrificial layer 102 using spin coating, and then patterned using exposure and development to obtain a patterned structure 103.

[0090] An Al2O3 layer 104 is deposited on the patterned structure 103 using ALD atomic layer deposition;

[0091] Then, a SiNx layer 105 was deposited by plasma-enhanced coupled vapor deposition (PECVD).

[0092] Then, an Al layer 106 was deposited using metal electron beam evaporation.

[0093] The sub-functional unit (comprising a substrate layer 51, a dielectric layer 52, and a metal layer 53) is fabricated using a lift-off process, see reference. Figure 19 ,

[0094] The fabricated sub-functional units were immersed in an acrylate elastomer (VHB 4905) liquid doped with NH4OH, as referenced. Figure 20 Under the action of NH4OH, the sacrificial layer 102 decomposes, and the elastomer is cured by heating (the temperature can be set according to actual needs, such as 50 degrees Celsius), thereby finally producing a metasurface functional structure. Figure 21The diagram only shows one sub-functional unit; in reality, it includes more than one sub-functional unit, it is just for illustration.

[0095] This invention also provides a scanning device, including the beam pointing adjustment structure described above.

[0096] This invention also provides a beam pointing adjustment method, which uses the above-described beam pointing adjustment structure for adjustment, and includes the following steps:

[0097] The functional expression of the target wave in free space is obtained based on the beam azimuth angle Φ and elevation angle θ of the desired target wave.

[0098] Based on the known expression for the reference wave, Aref = e^(-ikz), and the holographic principle, the expression for the interference wave formed by the reference wave and the target wave is obtained:

[0099]

[0100] Based on the above formula (1), the following formula is obtained by taking the real part using Euler's formula:

[0101]

[0102] According to the formula (2), the two-dimensional coordinates are obtained as (x i y i The result corresponding to the functional unit of ) is compared with a preset threshold using a binary method, and a voltage application signal is generated when the result is greater than the preset threshold, wherein the preset threshold is less than 1 and greater than zero;

[0103] Based on the received signal of applied voltage, voltage is applied to the corresponding block electrode in the first electrode layer 1 and the second electrode layer 2, thereby increasing the arrangement period of the sub-functional unit 5 in the corresponding functional unit 4.

[0104] For example, the preset threshold is 0.5. The setting of this preset threshold is not limited, as long as it is between 0 and 1.

[0105] For example, based on the received signal of the applied voltage, a voltage of 15-30V is applied to the corresponding block electrode in the first electrode layer 1 and the second electrode layer 2. The magnitude of the applied voltage is not limited here, and the magnitude of the applied voltage is related to the characteristics, thickness and degree of compression of the dielectric elastomer 3.

[0106] The development of nanophotonics and advanced manufacturing processes is considered capable of supporting or even replacing traditional LiDAR systems. In particular, several miniaturized beam control platforms, such as chip optical arrays and planar optics, can significantly reduce device size. Nanophotonics LiDAR platforms can achieve high image quality. This patent utilizes holographic principles to dynamically control the intensity of pixel units through the electrical properties of dielectric materials, thereby achieving dynamic digital beam focusing direction control across the visible light band for future advanced LiDAR systems.

[0107] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of the present invention, and the present invention is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A beam pointing adjustment structure, characterized in that, It includes a first electrode layer and a second electrode layer disposed opposite to each other, and a metasurface functional structure disposed between the first electrode layer and the second electrode layer; The first electrode layer includes at least one row of periodically arranged block electrodes, and the second electrode layer is a planar electrode, or the second electrode layer includes a plurality of block electrodes that correspond one-to-one with the block electrodes in the first electrode layer. The metasurface functional structure includes a dielectric elastomer and multiple functional units embedded in the dielectric elastomer. The multiple functional units are arranged in a one-to-one correspondence with the multiple block electrodes. Each functional unit includes multiple sub-functional units arranged periodically. The beam pointing adjustment structure also includes a control structure, which uses the holographic principle to apply voltage to the corresponding block electrode and the second electrode layer in the first electrode layer according to the direction of the desired target wave, so that the dielectric elastomer and the region corresponding to the corresponding block electrode deform, thereby changing the arrangement period of the multiple sub-functional units in the functional unit corresponding to the corresponding block electrode. The sub-functional unit includes a surface plasma, which comprises a substrate layer, a dielectric layer, and a metal layer stacked sequentially along a first direction, the first direction being the incident direction of the reference wave onto the metasurface functional structure.

2. The beam pointing adjustment structure according to claim 1, characterized in that, When a voltage is applied to the corresponding block electrode in the first electrode layer and the second electrode layer, the arrangement period of the plurality of sub-functional units in the functional unit corresponding to the block electrode increases.

3. The beam pointing adjustment structure according to claim 1, characterized in that, The dielectric layer is made of SiN. x The metal layer is made of Al, Ag, or Au.

4. The beam pointing adjustment structure according to claim 1, characterized in that, The base layer is made of Al2O3.

5. The beam pointing adjustment structure according to claim 1, characterized in that, The control structure includes: The target wave function expression acquisition unit is used to obtain the function expression of the target wave in free space based on the beam azimuth angle Φ and elevation angle θ of the desired target wave. ; The interferometric wave function expression acquisition unit is used to obtain the expression of the known reference wave. Based on the principle of holography, the expression for the interference wave formed by the reference wave and the target wave is obtained: (1), And according to formula (1), the following formula is obtained by taking the real part of Euler's formula: （2）； The control signal generation unit is used to obtain the two-dimensional coordinates as follows, according to formula (2): The result corresponding to the functional unit of the function is compared with a preset threshold using a binary method, and a voltage signal is generated when the result is greater than the preset threshold, wherein the preset threshold is less than 1 and greater than zero. An execution unit is configured to apply voltage to the corresponding block electrode in the first electrode layer and the second electrode layer according to the signal issued by the control signal generation unit.

6. A scanning device, characterized in that, Includes the beam pointing adjustment structure as described in any one of claims 1-5.

7. A beam pointing adjustment method, characterized in that, The beam pointing adjustment structure according to any one of claims 1-5 is used for adjustment, comprising the following steps: The functional expression of the target wave in free space is obtained based on the beam azimuth angle Φ and elevation angle θ of the desired target wave. ; Based on the known expression for the reference wave, Aref = e^(-ikz), and the holographic principle, the expression for the interference wave formed by the reference wave and the target wave is obtained: （1）， And based on the above formula (1), the following formula is obtained by taking the real part of Euler's formula: （2）； According to the formula (2), the two-dimensional coordinates are obtained as ( The result corresponding to the functional unit of ) is compared with a preset threshold using a binary method, and a voltage signal is generated when the result is greater than the preset threshold, wherein the preset threshold is less than 1 and greater than zero; Based on the received signal of applied voltage, voltage is applied to the corresponding block electrode and the second electrode layer in the first electrode layer, thereby increasing the arrangement period of the sub-functional units in the corresponding functional unit.

8. The beam pointing adjustment method according to claim 7, characterized in that, The preset threshold is 0.

5.

9. The beam pointing adjustment method according to claim 7, characterized in that, Based on the received signal of the applied voltage, an insertion voltage of 15-30V is applied to the corresponding block electrode in the first electrode layer and the second electrode layer.

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