Metasurface implementation method and device based on beam shaping, equipment and medium

Abstract

The invention discloses a metasurface implementation method and device based on beam shaping, equipment and a medium. The method comprises the following steps: acquiring light source parameters of an array light source incident to the metasurface device; calculating an initial focal length of a first phase of the metasurface device according to the light source parameters, and optimizing the distribution of the first phase; calculating an inter-hole angular spectrum difference and an angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameter and the initial focal length; and calculating angular spectrum distribution of a second phase of the metasurface device according to the inter-hole angular spectrum difference and the angular spectrum difference occupied by the single hole, and then optimizing the second phase distribution of the metasurface device by adopting a weighted angular spectrum component mode. On the basis, under the combined action of the optimized first phase distribution and second phase distribution, the incident light of the array light source is subjected to beam shaping, and the projection effect of high-cutoff line laser or homogenized light spots can be formed.

Description

Technical Field

[0001] The present invention relates to the field of optical technologies, and in particular, to a method, device, equipment, and medium for implementing a metasurface based on beam shaping. Background Art

[0002] Line lasers are widely used in fields such as three-dimensional scanning and ranging. In the traditional method of converting a point laser into a line laser, a cylindrical lens is required, but its total length and structural size do not meet the requirements of miniaturized design. In scenarios of working at a long distance, stray light and low cut-off performance lead to low energy utilization efficiency. Uniform spotlights are also widely used in lighting and measurement. Good cut-off performance can improve measurement accuracy and efficiency. The use of a Vcsel array light source provides a new solution to solve the problem of long-distance transmission caused by power. However, the beam shaping schemes for Vcsel array light sources often have problems such as complex devices, large system volume, low efficiency, and poor cut-off performance. Diffractive optical elements (DOEs) have the potential to replace optical lenses, but it is often difficult to improve their diffraction efficiency.

[0003] Line lasers are widely used in fields such as three-dimensional scanning and ranging. The traditional method of converting a point laser into a line laser is achieved through a cylindrical lens, but its total length and structural size are difficult to meet the requirements of miniaturized design. In scenarios of working at a long distance, stray light and low cut-off performance result in low energy utilization efficiency. Uniform spotlights are also widely used in the fields of lighting and measurement. Good cut-off performance can improve measurement accuracy and efficiency.

[0004] In the prior art, the use of a Vcsel array light source provides a new solution to solve the power problem in long-distance transmission. However, the beam shaping schemes for Vcsel array light sources generally have problems such as complex devices, large system volume, low efficiency, and poor cut-off performance. Diffractive optical elements (DOEs) have the potential to replace traditional optical lenses, but it is often difficult to improve their diffraction efficiency. Therefore, there is an urgent need for a scheme to perform beam shaping on a Vcsel array light source to improve the projection effect. Summary of the Invention

[0005] The objective of the present invention is to provide a method, device, equipment, and medium for implementing a metasurface based on beam shaping, aiming to solve the problem of how to perform efficient beam shaping on an array light source to improve the projection effect.

[0006] In a first aspect, an embodiment of the present invention provides a method for implementing a metasurface based on beam shaping, including: Obtaining the light source parameters of an array light source incident on a metasurface device; Calculating the initial focal length of the first phase of the metasurface device according to the light source parameters; Optimizing the first phase according to a set target focal length and modulation transfer function to confirm the first phase distribution; Calculate the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length; Calculate the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole; Perform beam shaping on the incident light of the array light source according to the angular spectrum distribution of the second phase and the optimized first phase distribution to form a line laser projection effect.

[0007] In a second aspect, an embodiment of the present invention provides a metasurface implementation device based on beam shaping, including: A parameter acquisition unit for acquiring the light source parameters of the array light source incident on the metasurface device; A focal length calculation unit for calculating the initial focal length of the first phase of the metasurface device according to the light source parameters; A first phase confirmation unit for optimizing the first phase according to the set target focal length and modulation transfer function to confirm the first phase distribution; An angular spectrum difference calculation unit for calculating the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length; An angular spectrum distribution calculation unit for calculating the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole; A first beam shaping unit for performing beam shaping on the incident light of the array light source according to the angular spectrum distribution of the second phase and the optimized first phase distribution to form a line laser projection effect.

[0008] In a third aspect, an embodiment of the present invention provides a computer device, which includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it implements the metasurface implementation method based on beam shaping described in the first aspect above.

[0009] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, where the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the processor executes the metasurface implementation method based on beam shaping described in the first aspect above.

[0010] The embodiment of the present invention discloses a method for realizing a metasurface based on beam shaping. The method includes: obtaining the light source parameters of an array light source incident on a metasurface device; calculating the initial focal length of the first phase of the metasurface device according to the light source parameters and optimizing the first phase distribution; calculating the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length; calculating the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole, and then optimizing the second phase distribution of the metasurface device by weighting the angular spectrum components. Based on this, under the combined action of the optimized first phase distribution and the second phase distribution, the present invention performs beam shaping on the incident light of the array light source, and can form a line laser with high cut-off performance or a projection effect of a homogenized light spot. Moreover, compared with the existing DOE device, the metasurface device improves the continuity of the phase distribution and effectively improves the diffraction efficiency. Description of the Drawings

[0011] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to these drawings.

[0012] Figure 1 A phase and transmittance curve diagram provided by an embodiment of the present invention; Figure 2 A schematic structural diagram of an array light source provided by an embodiment of the present invention; Figure 3 A schematic diagram of a line laser projection module provided by an embodiment of the present invention; Figure 4 A schematic diagram of the metasurface phase arrangement provided by an embodiment of the present invention; Figure 5 A schematic diagram of the projection effect of the shaped line laser provided by an embodiment of the present invention; Figure 6 A schematic flowchart of a method for realizing a metasurface based on beam shaping provided by an embodiment of the present invention; Figure 7 A schematic sub-flowchart of step S605 provided by an embodiment of the present invention; Figure 8 A schematic block diagram of a device for realizing a metasurface based on beam shaping provided by an embodiment of the present invention; Figure 9 A schematic block diagram of a computer device provided by an embodiment of the present invention. Detailed Embodiments

[0013] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0014] It should be understood that when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0015] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0016] It should be further understood that the term " / and" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0017] For the convenience of understanding the present invention, the metasurface device related to the present invention will be introduced first. The metasurface device includes a transparent substrate and nanostructures disposed on the substrate. The nanostructures are nanocolumns or nanopores. The material of the transparent substrate can be materials such as silicon dioxide and silicon nitride. Taking the nanocolumns as an example, the nanocolumns can be made of amorphous silicon. The size range of the nanocolumns is between 180 nm and 300 nm, and the specific value is determined by the phase and transmittance curve diagram as Figure 1 shown. The nanocolumns can be in the shapes of cylinders, rectangles, hexagons, triangles, etc. The height range of the nanocolumns is between 500 nm and 700 nm, and a height with a high transmittance is preferably selected within this range. The metasurface device of the present invention can perform beam shaping on the incident light of an array light source (refer to the vcsel light source shown in Figure 2 ) based on the following metasurface implementation method for beam shaping to form a projection effect of a line laser or a homogenized light spot.

[0018] Please refer to Figure 6 , Figure 6 , which is a schematic flowchart of the metasurface implementation method for beam shaping provided by the embodiment of the present invention.

[0019] As Figure 6 shown, the method includes steps S601 - S606.

[0020] S601. Obtain the light source parameters of the array light source incident on the metasurface device; In step S601, the array light source can be a lamp board with a plurality of light-emitting lamps arranged in an array, and the light source parameters include the length L x and width L y of the light-emitting area, the distribution of light-emitting holes in the light-emitting area, the diameter r of the light-emitting holes, and the hole pitch D of the light-emitting holes. Secondly, it is necessary to determine the line length z of the projected light (such as line laser) at a specified distance L z and line width V , or determine the length and width dimensions of the homogenized light spot.

[0021] S602. Calculate the initial focal length of the first phase of the metasurface device according to the light source parameters; For step S602, calculate the initial focal length of the first phase of the metasurface device according to the following formula f : ; ; Among them, L x represents the length of the light-emitting area, θ represents the opening angle of each line, z represents the specified distance to be projected, L z represents the specified distance z and the line length of the line laser at this distance.

[0022] S603. Optimize the first phase according to the set target focal length and modulation transfer function to confirm the first phase distribution; In step S603, the first phase is used to modulate the incident light to achieve operations such as focusing, deflecting, or homogenizing the incident light. Through simulation and iterative calculation, the first phase distribution is adjusted to meet the predetermined performance indicators in terms of the target focal length and modulation transfer function (MTF value).

[0023] For step S603, optimize the first phase distribution according to the following formula : ; Among them, M represents the weight coefficient, N represents the maximum number of even terms, i represents the number of even terms, A is a constant coefficient, ABelongs to the optimization variable; ρ is the normalized radius. By adjusting the constant coefficient A value, the first phase distribution is made to reach the set target focal length and modulation transfer function. The coverage range of the optimized first phase should be at least larger than the illuminated area of the light spot.

[0024] S604. Calculate the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length; In step S604, calculate the angular spectrum difference between holes according to the following formula and the angular spectrum difference occupied by a single hole : ; ; wherein, D represents the hole pitch of the light-emitting holes in the array light source, f represents the initial focal length of the first phase, r represents the diameter of the light-emitting holes in the array light source, λ represents the design wavelength, λ is determined by the wavelength of the array light source.

[0025] S605. Calculate the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole; In step S605, the angular spectrum distribution of the second phase is used to further determine the light field regulation characteristics of the metasurface device, including effects such as light focusing, deflection, beam splitting, and beam expansion.

[0026] As Figure 7 shown, step S605 may include: S701. Set the overlapping ratio of adjacent angular spectrum positions in the angular spectrum distribution of the second phase of the metasurface device; S702. Take the product of the angular spectrum difference occupied by a single hole and the overlapping ratio as the minimum angular spectrum of the angular spectrum distribution of the second phase; S703. Take the angular spectrum difference between holes as the maximum angular spectrum of the angular spectrum distribution of the second phase; S704. Obtain the angular spectrum distribution of the second phase according to the minimum angular spectrum and the maximum angular spectrum.

[0027] In steps S701 - S704, in order to ensure the uniform distribution of the line laser, the overlapping ratio of adjacent angular spectrum positions in the angular spectrum distribution of the second phase needs to reach more than 40%, and is distributed within the range determined by the angular spectrum difference between holes .

[0028] In some preferred embodiments, if the overlapping ratio in step S701 is set to 50%, the angular spectrum distribution of the second phase can be expressed as: ; Among them, F min represents the minimum angular spectrum of the second phase angular spectrum distribution, F max represents the maximum angular spectrum of the second phase angular spectrum distribution. It should be noted that the minimum angular spectrum and the maximum angular spectrum are not fixed values, and the minimum angular spectrum can float slightly; the value of the maximum angular spectrum can be the angular spectrum difference between holes , but generally it is smaller than the angular spectrum difference between holes to avoid overmodulation during the beam shaping process.

[0029] S606. According to the angular spectrum distribution of the second phase and the optimized first phase distribution, perform beam shaping on the incident light of the array light source to form a linear laser projection effect; In step S606, under the simultaneous action of the first phase and the second phase, the first phase is used to determine the outer contour of the final light spot, and the second phase is used to control the intensity distribution within the contour. For example, assuming that a linear laser projection needs to be projected, the first phase is used to focus the incident light of the array light source into discrete points at different angles, and the second phase is used to connect the discrete points through horizontal / vertical beam splitting and beam expansion to form a line, so as to obtain a high-cutoff linear laser projection.

[0030] The above steps S601 - S606 are mainly used to form a linear laser, which only needs to be operated in one dimension and can be extended to two dimensions for application to the formation of a homogenized light spot, and can be operated twice in one dimension.

[0031] In one embodiment, the metasurface implementation method based on beam shaping further includes steps S607 - S608.

[0032] S607. Optimize the second phase distribution of the metasurface device by weighting different angular spectrum components; In step S607, calculate the second phase distribution according to the following formula : ; Among them, m represents the total number of phase distributions superimposed, α represents the weight coefficient, α the larger the value, the larger the corresponding angular spectrum component, λ represents the design wavelength, λ which is determined by the wavelength of the array light source, a i represents the tilt coefficient, j represents the imaginary unit, and all other parameters except the wavelength λ can participate in the optimization to optimize the second phase distribution.

[0033] S608. According to the optimized second phase distribution and the first phase distribution, perform beam shaping on the incident light of the array light source to form a homogenized spot projection effect.

[0034] In steps S607 - S608, by finely adjusting the weight coefficients of different angular spectrum components, the second phase distribution of the metasurface device can be further optimized, enabling it to cooperate with the first phase distribution to achieve more precise control of the incident light. This cooperative effect enables the incident light of the array light source to not only form a high - cutoff line laser projection but also a homogenized spot projection effect after passing through the metasurface device. The characteristic of the homogenized spot projection effect is that its light intensity distribution is uniform, without obvious hot spots or dark areas, which is particularly important for application scenarios requiring uniform illumination. In addition, by optimizing through weighting different angular spectrum components, the diffraction efficiency of the metasurface device can be further improved, making the beam shaping process more efficient and precise.

[0035] Based on the above steps S601 - S608, precise beam shaping of the incident light of the array light source is achieved, thereby enabling the formation of a projection effect of a high - cutoff line laser or a homogenized spot.

[0036] Based on the above - described metasurface implementation method based on beam shaping, taking the formation of a line laser as an example, the obtained metasurface device and the array light source can form a Figure 3 line laser projection module as shown; where 21 represents the array light source, 22 represents the metasurface device, and 23 represents the receiving screen.

[0037] Based on the above - described metasurface implementation method based on beam shaping, the first phase and the second phase jointly achieve the overall beam function of the metasurface device, and can achieve a Figure 4 joint display effect as shown. Due to the unique metasurface implementation method of the present invention, the continuity of the phase distribution is extremely good, effectively improving the diffraction efficiency of the metasurface and reducing the design difficulty.

[0038] Based on the above - described metasurface implementation method based on beam shaping, taking the formation of a line laser as an example, the first phase and the second phase jointly achieve the overall beam function of the metasurface device, and can achieve a Figure 5 line laser projection effect as shown, which can achieve high cutoff and uniformity.

[0039] The embodiment of the present invention further provides a metasurface implementation device based on beam shaping. This metasurface implementation device based on beam shaping is used to execute any embodiment of the foregoing metasurface implementation method based on beam shaping. Specifically, please refer to Figure 8 , Figure 8 which is a schematic block diagram of the metasurface implementation device based on beam shaping provided by the embodiment of the present invention.

[0040] As shown Figure 8 in FIG. 2, the device 800 for implementing a metasurface based on beam shaping includes: a parameter acquisition unit 801, a focal length calculation unit 802, a first phase confirmation unit 803, an angular spectrum difference calculation unit 804, an angular spectrum distribution calculation unit 805, and a first beam shaping unit 806.

[0041] The parameter acquisition unit 801 is configured to acquire the light source parameters of the array light source incident on the metasurface device; The focal length calculation unit 802 is configured to calculate the initial focal length of the first phase of the metasurface device according to the light source parameters; The first phase confirmation unit 803 is configured to optimize the first phase according to the set target focal length and modulation transfer function to confirm the first phase distribution; The angular spectrum difference calculation unit 804 is configured to calculate the inter-aperture angular spectrum difference and the angular spectrum difference occupied by a single aperture under the action of the first phase according to the light source parameters and the initial focal length; The angular spectrum distribution calculation unit 805 is configured to calculate the angular spectrum distribution of the second phase of the metasurface device according to the inter-aperture angular spectrum difference and the angular spectrum difference occupied by a single aperture; The first beam shaping unit 806 is configured to perform beam shaping on the incident light of the array light source according to the angular spectrum distribution of the second phase and the optimized first phase distribution to form a line laser projection effect.

[0042] As shown Figure 8 in FIG. 3, the metasurface device 800 based on beam shaping further includes: a second phase confirmation unit 807 and a second beam shaping unit 808.

[0043] The second phase confirmation unit 807 is configured to optimize the second phase distribution of the metasurface device by weighting different angular spectrum components; The second beam shaping unit 808 is configured to perform beam shaping on the incident light of the array light source according to the optimized second phase distribution and the first phase distribution to form a homogenized spot projection effect.

[0044] Under the combined action of the optimized first phase distribution and the second phase distribution, the device performs beam shaping on the incident light of the array light source, and can form a projection effect of a high-cutoff line laser or a homogenized spot. Moreover, the metasurface device improves the continuity of the phase distribution compared with the existing DOE device, effectively improving the diffraction efficiency.

[0045] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working processes of the above-described device and units can refer to the corresponding processes in the foregoing method embodiments, and will not be described herein again.

[0046] The above-mentioned device for implementing a metasurface based on beam shaping can be implemented in the form of a computer program, which can run on a computer device as shown in Figure 9 .

[0047] Please refer to Figure 9 , Figure 9 , which is a schematic block diagram of the computer device provided by an embodiment of the present invention. The computer device 900 is a server, and the server can be an independent server or a server cluster composed of multiple servers.

[0048] Referring to Figure 9 , the computer device 900 includes a processor 902, a memory, and a network interface 905 connected through a system bus 901. Among them, the memory can include a non-volatile storage medium 903 and an internal memory 904.

[0049] The non-volatile storage medium 903 can store an operating system 9031 and a computer program 9032. When the computer program 9032 is executed, the processor 902 can be caused to execute a method for implementing a metasurface based on beam shaping.

[0050] The processor 902 is used to provide computing and control capabilities to support the operation of the entire computer device 900.

[0051] The internal memory 904 provides an environment for the operation of the computer program 9032 in the non-volatile storage medium 903. When the computer program 9032 is executed by the processor 902, the processor 902 can be caused to execute a method for implementing a metasurface based on beam shaping.

[0052] The network interface 905 is used for network communication, such as providing the transmission of data information, etc. Those skilled in the art can understand that Figure 9 the structure shown in

[0053] is only a block diagram of some structures related to the solution of the present invention, and does not constitute a limitation on the computer device 900 to which the solution of the present invention is applied. The specific computer device 900 may include more or fewer components than those shown in the figure, or combine some components, or have different component arrangements. Figure 9 Those skilled in the art can understand that Figure 9 the embodiment of the computer device shown in

[0054] It should be understood that in the embodiments of the present invention, the processor 902 may be a central processing unit (CPU), and the processor 902 may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0055] In another embodiment of the present invention, a computer-readable storage medium is provided. The computer-readable storage medium may be a non-volatile computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for implementing a metasurface based on beam shaping according to the embodiments of the present invention is realized.

[0056] The storage medium is a physical, non-transitory storage medium, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a magnetic disk, or an optical disc, etc., which are all physical storage media that can store program codes.

[0057] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described devices, apparatuses, and units can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein.

[0058] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of various equivalent modifications or substitutions within the technical scope disclosed by the present invention, and these modifications or substitutions should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for implementing a metasurface based on beam shaping, characterized in that Comprising: Obtaining the light source parameters of the array light source incident on the metasurface device; Calculating the initial focal length of the first phase of the metasurface device according to the light source parameters; Optimizing the first phase according to the set target focal length and modulation transfer function to confirm the first phase distribution; Calculating the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length; Calculating the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole; Performing beam shaping on the incident light of the array light source according to the angular spectrum distribution of the second phase and the optimized first phase distribution to form a line laser projection effect.

2. The method for realizing a metasurface based on beam shaping according to claim 1, wherein Further comprising: Optimizing the second phase distribution of the metasurface device by weighting different angular spectrum components; Performing beam shaping on the incident light of the array light source according to the optimized second phase distribution and the first phase distribution to form a homogenized spot projection effect.

3. The method for realizing a metasurface based on beam shaping according to claim 2, characterized in that The calculating the initial focal length of the first phase of the metasurface device according to the light source parameters includes: Calculate the initial focal length of the first phase of the metasurface device according to the following formula f :[[]]END]] ； ； Among them, L x represents the length of the light-emitting area, θ represents the opening angle of each line, z represents the specified distance to be projected, L z represents the specified distance z and the line length of the line laser under the specified distance.

4. The method for realizing a metasurface based on beam shaping according to claim 1, wherein The optimizing the first phase according to the set target focal length and modulation transfer function to confirm the first phase distribution includes: Calculate the first phase distribution according to the following formula : ； Among them, M represents the weight coefficient, N represents the maximum number of terms of the even terms, i represents the number of terms of the even terms, A is the constant coefficient, A belongs to the optimization variable; ρ is the normalization radius.

5. The method for realizing a metasurface based on beam shaping according to claim 1, characterized in that, The calculating the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length includes: Calculate the angular spectrum difference between the holes according to the following formula and the angular spectrum difference occupied by a single hole : ； ； Among them, D represents the pitch of the light-emitting holes in the array light source, f represents the initial focal length of the first phase, r represents the diameter of the light-emitting holes in the array light source, λ represents the design wavelength, λ which is determined by the wavelength of the array light source.

6. The method for implementing a metasurface based on beam shaping according to claim 1, wherein The calculating the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole includes: Setting the overlapping ratio of adjacent angular spectrum positions in the angular spectrum distribution of the second phase of the metasurface device; Taking the product of the angular spectrum difference occupied by a single hole and the overlapping ratio as the minimum angular spectrum of the angular spectrum distribution of the second phase; Taking the angular spectrum difference between holes as the maximum angular spectrum of the angular spectrum distribution of the second phase; Obtaining the angular spectrum distribution of the second phase according to the minimum angular spectrum and the maximum angular spectrum.

7. The method for implementing a metasurface based on beam shaping according to claim 2, wherein The optimizing the second phase distribution of the metasurface device by weighting different angular spectrum components includes: Calculate the second phase distribution according to the following formula : ； Among them, m represents the total number of phase distributions superimposed, α represents the weight coefficient, α The larger the value, the larger the corresponding angular spectrum component, λ represents the designed wavelength, λ which is determined by the wavelength of the array light source, a i represents the tilt coefficient, j represents the imaginary unit.

8. The method for realizing a metasurface based on beam shaping according to any one of claims 1 to 7, characterized in that The metasurface device includes a transparent substrate and nanostructures provided on the substrate, and the metasurface device is used for performing phase modulation on incident light to achieve the beam shaping.

9. A metasurface implementation device based on beam shaping, characterized in that, Comprising: A parameter acquisition unit for obtaining the light source parameters of the array light source incident on the metasurface device; A focal length calculation unit for calculating the initial focal length of the first phase of the metasurface device according to the light source parameters; A first phase confirmation unit for optimizing the first phase according to the set target focal length and modulation transfer function to confirm the first phase distribution; An angular spectrum difference calculation unit for calculating the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole under the action of the first phase according to the light source parameters and the initial focal length; An angular spectrum distribution calculation unit for calculating the angular spectrum distribution of the second phase of the metasurface device according to the angular spectrum difference between holes and the angular spectrum difference occupied by a single hole; A first beam shaping unit for performing beam shaping on the incident light of the array light source according to the angular spectrum distribution of the second phase and the optimized first phase distribution to form a line laser projection effect.

10. A computer device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, When the processor executes the computer program, the method for implementing a beam shaping-based metasurface according to any one of claims 1 to 8 is realized.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, causes the processor to execute the method for implementing a beam shaping-based metasurface according to any one of claims 1 to 8.

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