Liquid crystal phased array large-angle beam deflection system and beam deflection method

Abstract

The application discloses a liquid crystal phased array large-angle light beam deflection system, which comprises a laser, a polarizer, a first total reflection prism, a liquid crystal phased array and a second total reflection prism; the long-side transparent horizontal planes of the first total reflection prism and the second total reflection prism are in parallel and close to the two sides of the liquid crystal phased array; the line connecting the highest point of the i-th corner of the first total reflection prism and the lowest point of the i+1-th corner of the second total reflection prism is perpendicular to the long-side transparent horizontal planes of the two prisms; the polarizer is located on the upside of the liquid crystal phased array and adjacent to one end of the first total reflection prism; the liquid crystal phased array is spatially divided into a plurality of sub-aperture working areas, each sub-aperture corresponds to one or a pair of parallel reflection surfaces, and the monotonicity of the electrically controlled phase distribution of adjacent sub-apertures is mirror image about the center line. The application adopts a sub-aperture partition control mode and a light path return design, and can realize program-controlled continuous deflection of a light beam with large angle, high deflection efficiency and fast response speed based on a single spatial light modulator.

Description

Technical Field

[0001] This invention belongs to the fields of light field modulation, optical phased array control, and free-space optical communication technology, and specifically relates to a large-angle beam deflection system for a liquid crystal phased array, and a method for beam deflection using this deflection system. Background Technology

[0002] Free-space laser communication systems urgently require lightweight, agile, and large-angle beam deflection capabilities. Traditional mechanical laser control systems are slow, have low pointing accuracy, are complex, and cannot achieve multi-beam access at arbitrary angles. Optical phased array (OPA) technology not only enables fast, agile, and high-precision beam control but also allows for arbitrary beamforming. Furthermore, OPA devices are small in size, low in power consumption, lightweight, have no rotational inertia, and are easy to integrate, making them ideal for special platforms such as airborne, missile-borne, and spaceborne systems.

[0003] Currently, small deflection angles and low efficiency are the main technical bottlenecks limiting space-to-space laser communication, space-to-ground laser communication, short-range atmospheric laser communication, and quantum communication technologies. Whether it's lidar and laser collimators, laser guidance seekers and laser directed energy weapons, autonomous driving, laser communication networks, and new lidar systems, there is an unprecedented and urgent need for improved deflection angles and efficiency of space laser beams.

[0004] Currently, the deflection angle of a single optical phased array antenna is generally small, typically theoretically not exceeding ±10°. Due to manufacturing process errors and limitations in materials and equipment, the actual deflection angle is even smaller. In phased array beam deflection schemes, the deflection angle range and efficiency are generally contradictory; therefore, larger deflection angles result in lower efficiency. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a liquid crystal phased array large-angle beam deflection system that uses a refracting optical path design and a matching approach wavefront control algorithm to achieve a large deflection angle while maintaining high deflection efficiency and faster response speed, thereby enabling tracking, aiming and high-speed communication of fast targets. Furthermore, this invention provides a method for achieving large-angle beam deflection using this deflection system.

[0006] The objective of this invention is achieved through the following technical solution: a liquid crystal phased array large-angle beam deflection system, comprising a laser, a polarizer, a first total internal reflection prism, a liquid crystal phased array, and a second total internal reflection prism;

[0007] The first and second total internal reflection prisms have the same structure, each including a long transparent horizontal plane and multiple total reflection surfaces. The multiple total reflection surfaces are distributed in a sawtooth pattern. The long transparent horizontal planes of the first and second total internal reflection prisms are parallel and closely attached to the upper and lower sides of the liquid crystal phased array. The first and second total internal reflection prisms are arranged in a horizontally staggered spatial arrangement, with the first and second total internal reflection prisms offset by one total reflection surface. The line connecting the highest point of the i-th corner of the first total internal reflection prism and the lowest point of the (i+1)-th corner of the second total internal reflection prism is perpendicular to the long transparent horizontal plane of the two prisms.

[0008] The polarizer is located on the upper side of the liquid crystal phased array and is adjacent to one end of the first total internal reflection prism; the laser is located above the polarizer, and the first total internal reflection surface of the second total internal reflection prism is located below the polarizer.

[0009] The liquid crystal phased array is spatially divided into multiple sub-aperture working areas. Each sub-aperture corresponds to one or a pair of reflecting surfaces. The monotonicity of the electrically controlled phase distribution of adjacent sub-apertures is a mirror image of each other about the center line. The laser beam passes through the polarizer and the liquid crystal phased array in sequence and then enters the second total internal reflection prism. After being reflected multiple times between the second total internal reflection prism, the liquid crystal phased array, and the first total internal reflection prism, the beam exits from the last total internal reflection surface of the first total internal reflection prism.

[0010] The total reflection surfaces of the first and second total reflection prisms are coated with metal or dielectric films; the long transparent horizontal surfaces of both the first and second total reflection prisms are multi-layer coated anti-reflection surfaces.

[0011] Another objective of this invention is to provide a method for deflecting a large-angle beam using a liquid crystal phased array, which is implemented using the aforementioned large-angle beam deflection system for a liquid crystal phased array and includes the following steps:

[0012] Step 1, System Setup and Calibration: Build a large-angle beam deflection system for a liquid crystal phased array according to the optical path. Adjust the pitch and azimuth angles of the first and second total internal reflection prisms until the two ends of the prisms are aligned and in the same vertical space, and the long sides of the two prisms are parallel to the transparent horizontal planes. Move the first total internal reflection prism horizontally so that the line AB connecting the highest point A of the total reflection surface of the first total internal reflection prism and the lowest point B of the total reflection surface of the second total internal reflection prism is perpendicular to the long sides of the transparent horizontal planes of the two prisms. Then, emit a laser beam that is incident directly on the long side of the transparent horizontal plane of the second total internal reflection prism. Adjust the azimuth and pitch angles of the first total internal reflection prism so that the light emitted from the last total reflection surface of the first total internal reflection prism is parallel to the incident light from the first total reflection surface of the second total internal reflection prism.

[0013] The refractive index matching liquid is evenly coated on the outer side of the glass substrates on both sides of the liquid crystal phased array. Then it is placed between the first total reflection prism and the second total reflection prism. The first total reflection prism is moved vertically so that the liquid crystal phased array is in close contact with the long side transparent horizontal plane of the two total reflection prisms. Then it is cured by irradiation with ultraviolet light.

[0014] A polarizer is placed in close contact with the upper substrate glass of the liquid crystal phased array and one end of the first total internal reflection prism, and then cured by ultraviolet light.

[0015] Step 2: Set device parameters and operating wavelength: Set the spatial period of the liquid crystal phased array to d and the operating wavelength to λ;

[0016] Step 3: Set the target beam deflection angle, the number of sub-apertures, and the number of sub-aperture array elements: Set the target beam deflection angle to θ. xy =(θ x ,θ y The number of sub-apertures is N, and the number of sub-aperture array elements is M;

[0017] Step 4: Calculate the two-dimensional phase modulation of the target angle beam corresponding to the sub-aperture: Based on the right-hand Cartesian coordinate system, the phase at the near-field two-dimensional spatial coordinates (x′, y′) in the nth sub-aperture region is:

[0018]

[0019] in:

[0020]

[0021] Where k0 is the spatial frequency of the beam; θ x (n) and θ y (n) represent the two-dimensional spatial angle θ xy The deflection angles corresponding to the nth sub-aperture in the one-dimensional directions of x′ and y′ respectively;

[0022] The incident light amplitude is A, and the near field E of the outgoing light at the coordinates (x′, y′) of the nth sub-aperture is... near The relationship between (x′, y′), total phase φ(x′, y′), and amplitude A(x′, y′) is expressed as follows:

[0023]

[0024] Among them, T n Let be the laser transmittance of the nth sub-aperture of the liquid crystal phased array;

[0025] Step 5: Load the phase modulation signal: According to the phase-voltage mapping table of the spatial light modulator, find A(x′, y′) and A(x′, y′) for the near-field coordinate point (x′, y′). The corresponding voltage values ​​are obtained, and a voltage matrix for all regions of the liquid crystal optical phased array is generated. Finally, these are merged into a complete voltage bitmap, which is then loaded into the liquid crystal optical phased array modulator to achieve large-angle beam deflection based on a single liquid crystal phased array.

[0026] The beneficial effects of this invention are:

[0027] 1. This invention discloses a large-angle beam deflection system for a liquid crystal phased array. Based on a liquid crystal optical phased spatial light modulator, it employs a sub-aperture partitioning control method and an optical path folding design to achieve continuous spatial superposition of laser near-field phases. The optical path design is simple and can achieve large-angle, high-deflection-efficiency, and fast-response-speed programmable continuous beam deflection based on a single spatial light modulator. This method is applicable to large-angle beam deflection of other types of laser spatial light modulators, metasurface modulators, waveguide modulators, and microwave phased arrays.

[0028] 2. This invention supports continuously adjustable deflection angles and 2π-positioned outgoing light approach phase even when the phase modulation depth of a single device is extremely low or less than 2π. It solves the bottleneck problem that low-refractive-index-difference liquid crystal materials cannot be used as phased array materials under the same thickness.

[0029] 3. The system debugging steps of this invention are simple. Based on a single device, it ensures the consistency of each sub-aperture region, greatly reducing the alignment requirements of ordinary cascaded structures and the distortion problems caused by wavefront differences. Based on a spatial light modulator, a novel phase modulation algorithm with alternating phase gradient of sub-apertures is adopted, which realizes the ability to multiply the deflection angle range of a single liquid crystal phased array device. This can meet the needs of new-type lidar for large field of view and fast target tracking and aiming. Its large deflection angle and fast response capability provide theoretical feasibility support and technical guarantee for the realization of free space laser communication networking. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the large-angle beam deflection system of the liquid crystal phased array of the present invention.

[0031] Figure 2 This is a schematic diagram of the total internal reflection prism structure of the present invention;

[0032] Figure 3 This is a diagram showing the sub-aperture partitioning structure and near-field distribution of the liquid crystal phased array (OPA) in this embodiment;

[0033] Figure 4 This is a flowchart of the large-angle beam deflection method for liquid crystal phased arrays according to the present invention.

[0034] Explanation of reference numerals in the attached figures: 1: Laser; 2: First total internal reflection prism; 2-1: First total internal reflection surface of the first total internal reflection prism; 2-8: Eighth total internal reflection surface of the first total internal reflection prism; 2-9: Transparent horizontal plane of the long side of the first total internal reflection prism; 3: Polarizer; 4: Liquid crystal phased array; 5: Second total internal reflection prism; 5-1: First total internal reflection surface of the second total internal reflection prism; 5-2: Second total internal reflection surface of the second total internal reflection prism; 5-9: Transparent horizontal plane of the long side of the second total internal reflection prism. Detailed Implementation

[0035] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0036] like Figure 1 As shown, a large-angle beam deflection system for a liquid crystal phased array according to the present invention includes a laser 1, a polarizer 3, a first total internal reflection prism 2 (upper total internal reflection prism), a liquid crystal phased array (OPA) 4, and a second total internal reflection prism 5 (lower total internal reflection prism).

[0037] like Figure 2 As shown, the first total internal reflection prism 2 and the second total internal reflection prism 5 have the same structure, each including a long-side transparent horizontal plane and multiple total internal reflection surfaces. The multiple total internal reflection surfaces are serrated. The long-side transparent horizontal planes 2-9 (CD plane) and 5-9 (EF plane) of the first total internal reflection prism 2 and the second total internal reflection prism 5 are parallel and closely attached to the upper and lower sides of the liquid crystal phased array 3, that is, parallel and closely attached to the upper and lower substrate glass of the liquid crystal phased array 3. The first total internal reflection prism 2 and the second total internal reflection prism 5 are arranged in a horizontally staggered spatial arrangement, with the first total internal reflection prism 2 and the second total internal reflection prism 5 staggered by one total internal reflection surface. The line connecting the highest point of the i-th corner of the first total internal reflection prism 2 and the lowest point of the (i+1)-th corner of the second total internal reflection prism 5 is perpendicular to the long-side transparent horizontal plane of the two prisms. Figure 1 and Figure 2 As shown, the line AB connecting the highest point A of the first edge of the first total internal reflection prism 2 and the lowest point B of the second edge of the second total internal reflection prism 5 is perpendicular to the transparent horizontal plane of the long side of the two prisms; and so on, the line connecting the highest point of the second edge of the first total internal reflection prism 2 and the lowest point of the third edge of the second total internal reflection prism 5 is perpendicular to the transparent horizontal plane of the long side of the two prisms...

[0038] Polarizer 3 is located on the upper side of liquid crystal phased array 4 and is adjacent to one end of first total reflection prism 2; laser 1 is located above polarizer 3 and the first total reflection surface of second total reflection prism 5 is located below polarizer 3.

[0039] The liquid crystal phased array 4 is spatially divided into multiple sub-aperture working regions, each sub-aperture corresponding to one or a pair of parallel reflective surfaces. The monotonicity of the electrically controlled phase distribution of adjacent sub-apertures is a mirror image of each other about the center line; such as Figure 3As shown. Since the total reflection surfaces of the two reflecting prisms in this embodiment are uniformly distributed symmetrical structures with a total of 9 reflection regions, the sub-apertures of the liquid crystal phased array (OPA) are the same size and uniformly distributed on the liquid crystal phased array, represented as 4-1 to 4-9.

[0040] The emitted beam from laser 1 passes sequentially through polarizer 3 and liquid crystal phased array 4 before entering second total internal reflection prism 5. After multiple reflections between second total internal reflection prism 5, liquid crystal phased array 4, and first total internal reflection prism 2, the beam exits from the last total internal reflection surface of the first total internal reflection prism. This embodiment uses the number of reflecting surface units of the first total internal reflection prism 2 and the second total internal reflection prism 5 (8) as an example for demonstration and illustration. Figure 1 As shown, the light beam entering the second total internal reflection prism 5 first reaches the first total internal reflection surface 5-1 of the second total internal reflection prism. After total internal reflection by the first total internal reflection surface 5-1, the light beam exits to the second total internal reflection surface 5-2 of the second total internal reflection prism. After being reflected by the second total internal reflection surface 5-2, the light beam enters the liquid crystal phased array 4. After passing through the liquid crystal phased array 4, the light beam exits to the first total internal reflection surface 2-1 of the first total internal reflection prism. After being reflected by the first total internal reflection surface 2-1, the light beam exits to the second total internal reflection surface 2-2 of the first total internal reflection prism. After being reflected by the second total internal reflection surface 2-2, the light beam exits again to the liquid crystal phased array 4. The light beam then passes through the liquid crystal phased array 4 and enters the second total internal reflection prism 5. The beam is reflected sequentially through the third total reflection surface 5-3 of the total internal reflection prism, the fourth total reflection surface 5-4 of the second total internal reflection prism, the third total reflection surface 2-3 of the first total internal reflection prism, the fourth total reflection surface 2-4 of the first total internal reflection prism, the fifth total reflection surface 5-5 of the second total internal reflection prism, the sixth total reflection surface 5-6 of the second total internal reflection prism, the fifth total reflection surface 2-5 of the first total internal reflection prism, the sixth total reflection surface 2-6 of the first total internal reflection prism, the seventh total reflection surface 5-7 of the second total internal reflection prism, the eighth total reflection surface 5-8 of the second total internal reflection prism, the seventh total reflection surface 2-7 of the first total internal reflection prism, and the eighth total reflection surface 2-8 of the first total internal reflection prism, and finally exits from the eighth total reflection surface 2-8 of the first total internal reflection prism.

[0041] The total reflection surfaces of the first total reflection prism 2 and the second total reflection prism 5 are coated with metal or dielectric film. The long-side transparent horizontal surfaces 2-9 and 5-9 of the first total reflection prism 2 and the second total reflection prism 5 are both multi-layer coated anti-reflection surfaces. In this embodiment, the included angle between two adjacent total reflection surfaces is 90°, but not limited to 90°. Based on the reflection effect, the prism form is not limited to a reflecting pyramid prism, a one-piece molded prism, a one-piece molded all-metal reflector, or a discrete component adhesive structure. The reflecting surfaces of the first total reflection prism 2 and the second total reflection prism 5 are used to provide beam reflection, and the size and spatial period of adjacent reflecting surfaces are not limited to combinations such as equal, unequal, sparse, or discrete. The form of the first total reflection prism 2 and the second total reflection prism 5 is not limited to a one-dimensional prism or a one-dimensional reflecting surface, including various forms and dimensions of reflecting surfaces such as reflecting arc surfaces, trihedral pyramids, or circular arc pyramids. As long as light path reflection can be achieved, the shape, number, and other parameters of the reflecting surfaces can be set according to the application scenario.

[0042] The present invention provides a method for large-angle beam deflection of a liquid crystal phased array, which is implemented using the aforementioned large-angle beam deflection system for a liquid crystal phased array. The specific steps are as follows: Figure 4 As shown, it includes the following steps:

[0043] Step 1, System Setup and Calibration: Build a large-angle beam deflection system for the liquid crystal phased array according to the optical path. Adjust the elevation and azimuth angles of the first total internal reflection prism 2 and the second total internal reflection prism 5 until the two ends of the prisms are level and in the same vertical space (i.e., from...). Figure 1 In the middle view, the two prisms are aligned front and back respectively, and the long sides of the two prisms are parallel to the transparent horizontal plane; the first total internal reflection prism 2 is moved horizontally so that the line AB connecting the highest point A of the total reflection surface of the first total internal reflection prism 2 and the lowest point B of the total reflection surface of the second total internal reflection prism 5 is perpendicular to the long sides of the transparent horizontal plane of the two prisms; then a laser is emitted, which is incident on the long side of the transparent horizontal plane of the second total internal reflection prism 5. The azimuth and elevation angles of the first total internal reflection prism 2 are adjusted so that the light emitted from the last total reflection surface of the first total internal reflection prism 2 is parallel to the incident light from the first total reflection surface of the second total internal reflection prism 5.

[0044] The refractive index matching liquid is evenly coated on the outer side of the glass substrates on both sides of the liquid crystal phased array 4, and then placed between the first total reflection prism 2 and the second total reflection prism 5. The first total reflection prism 2 is moved vertically so that the liquid crystal phased array 4 is in close contact with the long side transparent horizontal surface of the two total reflection prisms, and then cured by ultraviolet light.

[0045] The polarizer 3 is placed in close contact with the upper substrate glass of the liquid crystal phase array 4 and one end of the first total internal reflection prism 2, and then cured by ultraviolet light.

[0046] Step 2: Set device parameters and operating wavelength: Set the spatial period of the liquid crystal phased array to d and the operating wavelength to λ;

[0047] Step 3: Set the target beam deflection angle, the number of sub-apertures, and the number of sub-aperture array elements: Set the target beam deflection angle to θ. xy =(θ x ,θ y The number of sub-apertures is N=9, and the number of sub-aperture array elements is M;

[0048] The system parameters built in this embodiment are shown in Table 1.

[0049] Table 1

[0050] caliber 45mm Number of sub-apertures 9 Sub-aperture element size 5×5μm Operating wavelength 1550nm Laser diameter 2mm

[0051] After the system is built, specific modulation information is loaded onto the spatial light modulator of the liquid crystal phased array, and the light field distribution characteristics of the outgoing light are observed. In the initial state, the liquid crystal phased array only has an initial small anchoring angle amplitude. Since the anchoring angle is consistent, the propagation direction of its outgoing light is in phase and parallel to the incident light. At this time, the system calibration is completed, the spatial position and state of the system are locked, the position of the outgoing light is recorded and marked as the far-field center 0 point;

[0052] Step 4: Calculate the two-dimensional phase modulation of the target angle beam corresponding to the sub-aperture: Based on the right-hand Cartesian coordinate system, the phase at the near-field two-dimensional spatial coordinates (x′, y′) in the nth sub-aperture region is:

[0053]

[0054] in:

[0055]

[0056] Where k0 is the spatial frequency of the beam; θ x (n) and θ y (n) represent the two-dimensional spatial angle θ xy The deflection angles corresponding to the nth sub-aperture in the one-dimensional directions of x′ and y′ respectively;

[0057] The incident light amplitude is A, and the near field E of the outgoing light at the coordinates (x′, y′) of the nth sub-aperture is... near The relationship between (x′, y′), total phase φ(x′, y′), and amplitude A(x′, y′) is expressed as follows:

[0058]

[0059] Among them, T n Let be the laser transmittance of the nth sub-aperture of the liquid crystal phased array;

[0060] Step 5: Load the phase modulation signal: According to the phase-voltage mapping table of the spatial light modulator, find A(x′, y′) and A(x′, y′) for the near-field coordinate point (x′, y′). The corresponding voltage values ​​are obtained, and a voltage matrix for all regions of the liquid crystal optical phased array is generated. Finally, these are merged into a complete voltage bitmap, which is then loaded into the liquid crystal optical phased array modulator to achieve large-angle beam deflection based on a single liquid crystal phased array.

[0061] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the spirit of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A large-angle beam deflection system for a liquid crystal phased array, characterized in that, It includes a laser (1), a polarizer (3), a first total internal reflection prism (2), a liquid crystal phased array (4), and a second total internal reflection prism (5); The first total internal reflection prism (2) and the second total internal reflection prism (5) have the same structure, each including a long side transparent horizontal plane and multiple total reflection surfaces. The multiple total reflection surfaces are distributed in a sawtooth pattern. The long side transparent horizontal planes of the first total internal reflection prism (2) and the second total internal reflection prism (5) are parallel and closely attached to the upper and lower sides of the liquid crystal phased array (4). The first total internal reflection prism (2) and the second total internal reflection prism (5) are arranged in a horizontally staggered spatial arrangement. The first total internal reflection prism (2) and the second total internal reflection prism (5) are staggered by one total reflection surface. The line connecting the highest point of the i-th corner of the first total internal reflection prism (2) and the lowest point of the (i+1)-th corner of the second total internal reflection prism (5) is perpendicular to the long side transparent horizontal plane of the two prisms. The polarizer (3) is located on the upper side of the liquid crystal phased array (4) and is adjacent to one end of the first total reflection prism (2); the laser (1) is located above the polarizer (3), and the first total reflection surface of the second total reflection prism (5) is located below the polarizer (3); The liquid crystal phased array (4) is divided into multiple sub-aperture working areas in space. Each sub-aperture corresponds to one or a pair of reflecting surfaces. The monotonicity of the electronically controlled phase distribution of adjacent sub-apertures is a mirror image of each other about the center line. The emitted beam of the laser (1) passes through the polarizer (3) and the liquid crystal phased array (4) in sequence and then enters the second total reflection prism. After the beam is reflected back and forth multiple times between the second total reflection prism (5), the liquid crystal phased array (4) and the first total reflection prism (2), it is emitted from the last total reflection surface of the first total reflection prism.

2. The large-angle beam deflection system for a liquid crystal phased array according to claim 1, characterized in that, The total reflection surfaces of the first total reflection prism (2) and the second total reflection prism (5) are coated with metal or dielectric film; the long transparent horizontal surfaces of the first total reflection prism (2) and the second total reflection prism (5) are both multi-layer coated anti-reflection surfaces.

3. A method for large-angle beam deflection of a liquid crystal phased array, implemented using the large-angle beam deflection system of a liquid crystal phased array as described in claim 1 or 2, characterized in that... Includes the following steps: Step 1, System Setup and Calibration: Build a large-angle beam deflection system for a liquid crystal phased array according to the optical path. Adjust the pitch and azimuth angles of the first total internal reflection prism (2) and the second total internal reflection prism (5) until the two ends of the prisms are aligned and in the same vertical space, and the long sides of the two prisms are parallel to each other. Move the first total internal reflection prism (2) horizontally so that the line AB connecting the highest point A of the total reflection surface of the first total internal reflection prism (2) and the lowest point B of the total reflection surface of the second total internal reflection prism (5) is perpendicular to the long sides of the two prisms. Then emit a laser beam that is incident on the long side of the transparent horizontal surface of the second total internal reflection prism (5). Adjust the azimuth and pitch angles of the first total internal reflection prism (2) so that the outgoing light from the last total reflection surface of the first total internal reflection prism (2) is parallel to the incident light from the first total reflection surface of the second total internal reflection prism (5). The refractive index matching liquid is evenly coated on the outer side of the glass substrate on both sides of the liquid crystal phase array (4), and then placed between the first total reflection prism (2) and the second total reflection prism (5). The first total reflection prism (2) is moved vertically so that the liquid crystal phase array (4) is in close contact with the long side transparent horizontal surface of the two total reflection prisms, and then cured by ultraviolet light. A polarizer (3) is placed in close contact with the upper substrate glass of the liquid crystal phase array (4) and one end of the first total internal reflection prism (2), and cured by ultraviolet light. Step 2: Set device parameters and operating wavelength: Set the spatial period of the liquid crystal phased array to d and the operating wavelength to λ; Step 3, setting target beam deflection angle, sub-aperture number and sub-aperture array unit number: setting target beam deflection angle as θ xy =(θ x , θ y ), sub-aperture number as N, and sub-aperture array unit number as M; Step 4: Calculate the two-dimensional phase modulation of the target angle beam corresponding to the sub-aperture: Based on the right-hand Cartesian coordinate system, the phase at the near-field two-dimensional spatial coordinates (x′, y′) in the nth sub-aperture region is: in: wherein k0 is the spatial frequency of the beam; θ x (n) and θ y (n) are two-dimensional spatial angles θ xy are the deflection angles in the x' and y' one-dimensional directions, respectively, corresponding to the n-th sub-aperture. The incident light amplitude is A, and the near field E of the outgoing light at the coordinates (x′, y′) of the nth sub-aperture is... near The relationship between (x′, y′), total phase φ(x′, y′), and amplitude A(x′, y′) is expressed as follows: Among them, T n Let be the laser transmittance of the nth sub-aperture of the liquid crystal phased array; Step 5: Load the phase modulation signal: According to the phase-voltage mapping table of the spatial light modulator, find A(x′, y′) and A(x′, y′) for the near-field coordinate point (x′, y′). The corresponding voltage values ​​are obtained, and a voltage matrix is ​​generated for all regions of the liquid crystal optical phased array. Finally, these are merged into a complete voltage bitmap, which is then loaded into the liquid crystal optical phased array modulator to achieve large-angle beam deflection based on a single liquid crystal phased array.

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