Two-dimensional scanning OPA system based on superlens array

Abstract

The present invention discloses a two-dimensional scanning OPA system based on a superlens array, which belongs to the field of superlens technology and OPA technology. By combining the superlens array with OPA (synthetic aperture laser radar), two-dimensional scanning of the light beam is realized, and the scanning angle can reach ±30°. The superlens array is composed of a plurality of superlens unit structures, each superlens unit structure corresponds to an OPA transmitting unit, and the deflection angle of the outgoing light beam can be changed by horizontally moving the superlens unit structure. The invention solves the problem of the small deflection angle of the OPA outgoing light beam, which is conducive to realizing a laser radar system with large-angle two-dimensional scanning.

Description

Technical Field

[0001] The present invention relates to the fields of superlens technology and OPA technology, and in particular to a two-dimensional scanning OPA system based on a superlens array. Background Art

[0002] LiDAR is an advanced detection method that integrates laser technology and modern photoelectric detection technology. It is mainly composed of a transmitting system, a receiving system and an information processing module. It detects the target by emitting a laser beam and obtains the target's position information, speed and other characteristic parameters from the reflected light. LiDAR usually uses a wavelength in the range of 800-1550nm, with the most commonly used wavelengths being 905nm and 1550nm. The key indicators for its performance evaluation include detection distance, scanning angle, resolution and scanning rate.

[0003] Traditional LiDAR relies on complex mechanical beam scanning modules, which leads to complex system structure, difficult assembly, large size, high power consumption, high cost, and low scanning rate, which makes it difficult to meet the modern demand for miniaturization and lightweight. With the continuous advancement of silicon-based optoelectronics, all-solid-state LiDAR has gradually attracted widespread attention, especially the scanning scheme based on optical phased array (OPA), which has achieved remarkable research results due to its advantages of compactness, stability, durability and low cost. However, the current all-solid-state LiDAR still has limitations in terms of field of view. The scanning angle of high-resolution systems usually does not exceed 10°, and the resolution inevitably decreases as the angle increases. Therefore, how to maintain high resolution and compact design while expanding the scanning angle has become a problem that needs to be solved urgently.

[0004] In order to solve the above problems, some solutions have been proposed. For example, the liquid crystal metasurface changes the arrangement direction of the liquid crystal by regulating the external electric field, thereby controlling the deflection of light, but due to the long response time of the liquid crystal, this solution will lead to a decrease in the scanning rate. If an optical system composed of refractive lenses is used, although it will not affect the scanning rate, it will significantly increase the volume of the system. In contrast, the superlens optical system can expand the scanning angle of the lidar in a smaller volume without sacrificing the scanning rate. However, the direct manufacture of large-aperture superlenses faces process challenges and high costs. The present invention achieves the expansion of the scanning angle by mechanically moving the superlens array, significantly reducing the system volume, and can be combined with the OPA array to provide a higher scanning rate, which has important scientific significance and practical application value. Summary of the invention

[0005] The purpose of the present invention is to address the deficiencies of the prior art and propose a two-dimensional scanning OPA system based on a superlens array, which solves the problem of small deflection angle of the OPA output light beam.

[0006] The present invention solves the above technical problems through the following technical means: a two-dimensional scanning OPA system based on a superlens array, the system comprising:

[0007] On-chip two-dimensional OPA array for outgoing beams;

[0008] A superlens array is placed at intervals from the on-chip two-dimensional OPA array, and is used to receive the light beam emitted from the OPA and deflect the light beam;

[0009] The OPA array phase measurement compensation module is used to compensate the piston phase of the OPA array to achieve large-angle continuous scanning of the output beam.

[0010] Furthermore, the super lens array includes one or two layers of double-sided super lens arrays.

[0011] Furthermore, the double-sided superlens array comprises a first nanostructure layer, a base layer, and a second nanostructure layer, wherein the first nanostructure layer and the second nanostructure layer are respectively connected to the front and rear surfaces of the base layer to achieve light beam deflection.

[0012] Furthermore, the superlens array is placed in parallel with the OPA, and the superlens array units correspond to the OPA units one by one, and the distance between them is a preset lens focal length f.

[0013] Furthermore, the superlens array can be translated relative to the OPA, and for any scanning angle of the OPA unit within a set angle range, the corresponding superlens unit adjusts the deflection angle of the outgoing light beam through relative translation.

[0014] Furthermore, the OPA array phase measurement and compensation module includes a laser generating device, an optical fiber beam splitter, an optical fiber amplifier, an integrated optical chip, a phase measurement chip, and a phase compensation chip; the integrated optical chip includes an optical fiber-waveguide coupler, an OPA unit, an on-chip thin-film lithium niobate phase modulator, and an on-chip photodetector; the phase measurement chip includes an on-chip phase modulator and an on-chip photodetector; the laser generated by the laser generating device is divided into N paths by the optical fiber beam splitter, and each path passes through the optical fiber amplifier and then enters the on-chip photodetector of the integrated optical chip through the optical fiber-waveguide coupler, and the laser passes through the on-chip thin-film lithium niobate phase modulator and then is emitted from the OPA unit on the integrated optical chip; a small part of each laser entering the integrated optical chip is separated and enters the phase measurement chip; the phase measurement chip calculates the phase difference between two adjacent laser paths and outputs the signal to the phase compensation chip; the phase compensation chip outputs a control signal to the on-chip thin-film lithium niobate phase modulator on the integrated optical chip to compensate for the phase difference.

[0015] Furthermore, the OPA array phase measurement chip detects and calculates the phase difference of adjacent OPA main laser light paths through a phase shift measurement method or a frequency mixing method.

[0016] Furthermore, the phase compensation chip uses a PID control algorithm, an SPGD algorithm, a hill climbing algorithm or a particle swarm optimization algorithm to output a control signal to a phase modulator on an integrated optical chip, so that the phase difference between adjacent OPA main laser optical paths is locked at a fixed value to compensate for the OPA array piston phase, thereby achieving large-angle continuous scanning.

[0017] Furthermore, the OPA array phase measurement compensation module can individually control the phase of each OPA unit, allowing it to have any phase shift of 0 to 2π radians with adjacent OPA units.

[0018] Furthermore, the metalens unit deflects all OPA unit outgoing light beams within the divergence angle range to the same outgoing angle under the same relative translation amount.

[0019] The beneficial effects of the present invention are:

[0020] 1. The present invention allows the light beam emitted by the OPA to pass through the superlens array, deflects the emitted light beam, and the light beam divergence angle is small, which solves the problem of the small deflection angle of the OPA light beam, and is conducive to realizing a laser radar system with large-angle two-dimensional scanning.

[0021] 2. By translating the superlens array and changing the relative position of the superlens array and OPA, the deflection angle of the outgoing beam can be adjusted. Therefore, the movement of the superlens array can be mechanically controlled to automatically adjust the outgoing beam angle, which is convenient and quick.

[0022] 3. Using super lenses instead of traditional lenses has fewer structural parts and is smaller in mass and volume. It meets the current requirements for small and lightweight optical devices and is easy to integrate into detection equipment such as autonomous driving vehicles and security monitoring.

[0023] 4. The present invention controls the phase of each OPA unit individually through a phase measurement compensation chip to compensate for the piston phase of the sub-aperture, thereby avoiding the scanning discontinuity phenomenon caused by a blazed grating-like phase structure when multiple sub-apertures form an equivalent large aperture, thereby achieving continuous scanning at a large angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the unit structure of a two-dimensional scanning OPA system (two-layer double-sided superlens array) based on a superlens array according to an embodiment of the present invention.

[0025] Figure 2 1 is a top view of a nanostructure array according to an embodiment of the present invention.

[0026] Figure 3 It is a schematic diagram of the nano unit structure in the nano structure array according to an embodiment of the present invention.

[0027] Figure 4 It is a unit operation diagram of a two-dimensional scanning OPA system (two-layer double-sided superlens array) based on a superlens array according to an embodiment of the present invention.

[0028] Figure 5 It is an inverse point spread function image of a two-dimensional scanning OPA system (two-layer double-sided superlens array) based on a superlens array in an embodiment of the present invention.

[0029] Figure 6 It is an inverse MTF image of a two-dimensional scanning OPA system (two-layer double-sided superlens array) based on a superlens array in an embodiment of the present invention.

[0030] Figure 7 It is a reverse Strehl ratio curve of a two-dimensional scanning OPA system (two-layer double-sided superlens array) based on a superlens array in an embodiment of the present invention.

[0031] Figure 8 It is a unit operation diagram of a two-dimensional scanning OPA system (a layer of double-sided superlens array) based on a superlens array according to an embodiment of the present invention.

[0032] Fig. 9 It is an inverse point spread function image of a two-dimensional scanning OPA system (a layer of double-sided superlens array) based on a superlens array in an embodiment of the present invention.

[0033] Fig.10 It is an inverse MTF image of a two-dimensional scanning OPA system (a layer of double-sided superlens array) based on a superlens array in an embodiment of the present invention.

[0034] Fig.11 It is a reverse Strehl ratio curve of a two-dimensional scanning OPA system (a layer of double-sided superlens array) based on a superlens array in an embodiment of the present invention.

[0035] Fig.12 It is a schematic diagram of the principle structure of a phase measurement compensation module in one embodiment of the present invention.

[0036] Fig.13 It is a schematic diagram of the beam expansion effect of an OPA array superimposed on a superlens array in one embodiment of the present invention.

[0037] Fig.14 It is a schematic diagram of the principle of OPA unit compensation piston phase in one embodiment of the present invention.

[0038] Numbers in the figure:

[0039] 100, OPA unit;

[0040] 200, first super lens array unit; 210, first nanostructure array unit; 220, base layer; 230, second nanostructure array;

[0041] 300, second super lens array unit; 310, first nanostructure array unit; 320, base layer; 330, second nanostructure array;

[0042] S, beam; S1, normal beam; S2, partial beam;

[0043] 1. Laser generating device; 2. Fiber beam splitter; 3. Fiber amplifier; 4. Fiber-waveguide coupler; 5. On-chip phase shifter; 6. On-chip photodetector; 7. OPA unit; 8. Phase measurement chip; 9. Phase compensation chip. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] Embodiment 1:

[0046] like Figure 1 As shown, the present invention provides a two-dimensional scanning OPA system based on a superlens array, which adopts a two-layer double-sided superlens array, including an OPA unit 100, a first superlens array unit 200 and a second superlens array unit 300 arranged at intervals.

[0047] The OPA unit 100 emits light in the form of a point light source;

[0048] The first super lens array unit 200 is spaced apart from the OPA 100 and is used to perform a first deflection on the light emitted by the OPA unit 100, and the distance between the two is a preset lens focal length f;

[0049] The second super lens array unit 300 is placed at an interval with the first super lens array unit 200, and is used to perform a second deflection on the light deflected for the first time by the first super lens array unit 200, and the distance between the two is a preset lens spacing d.

[0050] In this embodiment, the light beam S includes a positive light beam S1 and a deflected light beam S2, so as to meet the deflection of incident light beams at various positions and achieve a two-dimensional scanning effect.

[0051] The first super lens array unit 200 includes a first nanostructure array 210, a first substrate layer 220 and a second nanostructure array 230; the first nanostructure array 210 and the second nanostructure array 230 are respectively connected to the front and back surfaces of the substrate layer 220;

[0052] The second super lens array unit 300 includes a third nanostructure array 310, a second substrate layer 320 and a fourth nanostructure array 330; the first nanostructure array 310 and the second nanostructure array 330 are connected to the front and back surfaces of the substrate layer 320 respectively;

[0053] The first substrate layer 220 and the second substrate layer 320 are used to transmit the light beam, and the first nanostructure array 210 and the second nanostructure array 230 , the third nanostructure array 310 and the fourth nanostructure array 330 are used to deflect the light beam.

[0054] The wavelength of the OPA output beam is selected as the central wavelength of the two-dimensional scanning OPA system based on the superlens array in this embodiment, and the lens focal length f and the lens spacing d are preset.

[0055] The OPA unit 100 , the first super lens array unit 200 , and the second super lens array unit 300 are of equal size.

[0056] like Figure 2 As shown, the first super lens array unit 200 and the second super lens array unit 300 have substantially the same structure, but have different thickness dimension parameters and nanostructure array arrangements.

[0057] The first substrate layer 220 and the second substrate layer 320 are used to transmit light beams and are made of low-loss materials with low dielectric constants, such as quartz glass.

[0058] The first nanostructure array 210 and the second nanostructure array 230 , the third nanostructure array 310 and the fourth nanostructure array 330 are used to realize beam deflection. The working wavelength is designed as the central wavelength, and the beam deflection function is realized by periodically arranging nanostructure units.

[0059] In order to meet the need of beam deflection, the polynomial coefficients of the phase distribution are optimized so that the response of the light at different angles meets the requirements. The phase distributions satisfied by the first nanostructure array 210 and the second nanostructure array 230, the third nanostructure array 310 and the fourth nanostructure array 330 are as follows:

[0060]

[0061] Wherein, k=N, N is an integer greater than or equal to 1, (k=1, 2, 3, 4) are the phase distributions of the first nanostructure array 210, the second nanostructure array 230, the third nanostructure array 310 and the fourth nanostructure array 330, respectively. is the diffraction order, are the polynomial coefficients, is the actual annulus radius, is the normalized radius.

[0062] Polynomial coefficients It is determined through system optimization. During optimization, the light is transmitted in reverse, which is equivalent to focusing parallel light beams incident from different fields of view at different positions on the OPA. The weighted sum of the imaging quality (characterized by Strehl ratio) of light rays at different incident angles is used as the evaluation function for optimization:

[0063]

[0064] in For different incident angles, is the corresponding weight, is the corresponding Strehl ratio. In this embodiment, it is calculated every 5° The sum is then used to obtain the total optimization function value. The larger the Strehl ratio, the higher the imaging quality. Therefore, the polynomial coefficients of the nanostructure array are adjusted. To increase the optimization function FOM, and at the same time adjust , so that the Strehl ratio for all incident angles from 0° to 30° can be above 0.8, that is, there is a high imaging effect within the 60° field of view, that is, when the OPA emits light at different positions, it can obtain output light with different deflection angles.

[0065] like Figure 3 As shown, the first nanostructure array 210 and the second nanostructure array 230, the third nanostructure array 310 and the fourth nanostructure array 330 can be made of the same material or different materials, and the preparation material can be a high dielectric constant, low loss visible light dielectric material or semiconductor material, such as single crystal silicon, titanium dioxide or silicon nitride, etc. In this embodiment, the first nanostructure array 210 and the second nanostructure array 230, the third nanostructure array 310 and the fourth nanostructure array 330 are made of single crystal silicon, and the cross-sectional shape of the nanocolumn can be a square, a circle or a hole-shaped structure, etc., and can be specifically designed according to the actual functional effect.

[0066] The working process of this embodiment:

[0067] refer to Figure 4As shown in a, when the first super lens array unit 200 and the second super lens array unit 300 are facing the OPA unit 100, the positive light beam S1 emitted by the OPA passes through the second nanostructure array 230, the first substrate layer 220, the first nanostructure array 210, the fourth nanostructure array 330, the second substrate layer 320, and the third nanostructure array 310 in sequence, and is emitted as parallel light with a deflection angle of 0°.

[0068] refer to Figure 4 As shown in b, when the first super lens array unit 200 and the second super lens array unit 300 are translated a certain distance relative to the OPA unit 100, the light S2 emitted by the OPA passes through the second nanostructure array 230, the first substrate layer 220, the first nanostructure array 210, the fourth nanostructure array 330, the second substrate layer 320, and the third nanostructure array 310 in sequence, and is emitted as parallel light with a deflection angle of 30°.

[0069] Therefore, by changing the positions of the first super lens array unit 200 and the second super lens array unit 300 relative to the OPA unit 100, the deflection angle of the emitted light can be adjusted to obtain parallel light beams of different angles. Since the system is rotationally symmetric, a two-dimensional scanning effect can be achieved.

[0070] Embodiment 2:

[0071] In this embodiment, based on the above embodiment, the working wavelength is selected as 1550nm for testing.

[0072] The side lengths of the first super lens array unit 200, the second super lens array unit 300, and the OPA unit 100 are 0.4 mm.

[0073] The first base layer 220 is made of silicon dioxide and has a thickness of 0.1 mm.

[0074] The second base layer 320 is made of silicon dioxide and has a thickness of 0.1 mm.

[0075] The first nanostructure array 210 and the second nanostructure array 230 , the third nanostructure array 310 and the i-th nanostructure array 330 are made of single crystal silicon with a diameter of 0.4 mm.

[0076] The distance between the OPA unit 100 and the first super lens array unit 200 is preset to have a lens focal length f of 0.1 mm.

[0077] The preset lens spacing d between the first super lens array unit 200 and the second super lens array unit 300 is 0.1 mm.

[0078] In this embodiment, a two-dimensional scanning OPA system based on a superlens array has an f-number of 0.8, and a ratio of the clear aperture to the unit diameter is 0.8, indicating that the system utilization rate is high.

[0079] In this embodiment, an inverse point spread function image of a two-dimensional scanning OPA system based on a superlens array is shown as follows: Figure 5 As shown, the point spread function image of the incident light at 0° field of view is as follows Figure 5 As shown in a in the figure, the point spread function image of the incident light with a 30° field of view is as follows Figure 5 As shown in b, both have good focusing effects, indicating that when the system is running in the forward direction, the light emitted by the OPA can eventually obtain a good output parallel beam.

[0080] In this embodiment, the inverse MTF image of a two-dimensional scanning OPA system based on a superlens array is as follows: Figure 6 As shown, there is a good imaging effect, indicating that the light emitted by the OPA can eventually obtain a good output parallel beam when the system is running in the forward direction.

[0081] In this embodiment, a reverse Strehl ratio curve of a two-dimensional scanning OPA system based on a superlens array is as follows: Figure 7 As shown, they are all greater than 0.88, with good imaging effects, indicating that the light emitted by the OPA can eventually obtain a good output parallel beam when the system is running in the forward direction.

[0082] According to the above test results, when using two layers of double-sided metalenses, the light emitted by the OPA when the system is running in the forward direction can eventually obtain a good output parallel light beam, and by changing the position of the first metalens array unit 200 and the second metalens array unit 300 relative to the OPA unit 100, the deflection angle of the output light can be adjusted to obtain parallel light beams at different angles, thereby achieving a two-dimensional scanning effect.

[0083] Embodiment three:

[0084] In this embodiment, based on the above embodiment, the second super lens array unit 300 is removed, and only the first super lens array unit 200 is left, that is, a layer of double-sided super lens, such as Figure 8 shown.

[0085] The working wavelength was selected as 1550nm for the test.

[0086] The side length of the first super lens array unit 200 and the OPA unit 100 is 0.65 mm.

[0087] The first base layer 220 is made of silicon dioxide and has a thickness of 0.45 mm.

[0088] The first nanostructure array 210 and the second nanostructure array 230 are made of single crystal silicon with a diameter of 0.65 mm.

[0089] The distance between the OPA unit 100 and the first super lens array unit 200 is preset to have a lens focal length f of 0.35 mm.

[0090] In this embodiment, a two-dimensional scanning OPA system based on a superlens array has an f-number of 1.2, a ratio of the light aperture to the unit diameter of 0.5, and a system utilization rate that is lower than that of a two-layer double-sided superlens.

[0091] In this embodiment, an inverse point spread function image of a two-dimensional scanning OPA system based on a superlens array is shown as follows: Fig. 9 As shown, the point spread function image of the incident light at 0° field of view is as follows Fig. 9 As shown in a in the figure, the point spread function image of the incident light with a 30° field of view is as follows Fig. 9 As shown in b, both have good focusing effects, indicating that when the system is running in the forward direction, the light emitted by the OPA can eventually obtain a good output parallel beam.

[0092] In this embodiment, the inverse MTF image of a two-dimensional scanning OPA system based on a superlens array is as follows: Fig.10 As shown, there is a good imaging effect, indicating that the light emitted by the OPA can eventually obtain a good output parallel beam when the system is running in the forward direction.

[0093] In this embodiment, a reverse Strehl ratio curve of a two-dimensional scanning OPA system based on a superlens array is as follows: Fig.11 As shown, they are all greater than 0.8, with good imaging effects, indicating that the light emitted by the OPA can eventually obtain a good output parallel beam when the system is running in the forward direction.

[0094] According to the above test results, when using a layer of double-sided metalens, the light emitted by the OPA when the system is running in the forward direction can eventually obtain a good output parallel light beam, and by changing the position of the first metalens array unit 200 and the second metalens array unit 300 relative to the OPA unit 100, the deflection angle of the output light can be adjusted to obtain parallel light beams at different angles, thereby achieving a two-dimensional scanning effect, but the effect is slightly worse than that of two layers of double-sided metalens.

[0095] In one embodiment, the combined shape of the OPA array on the plane includes a circular, rectangular or any regular polygonal close-packed array; Fig.13 As shown, after the OPA array is combined with the superlens array, since each unit in the OPA array has a similar phase increment distribution when scanning a certain angle, a phase structure similar to a blazed grating will be formed, resulting in the inability to perform continuous scanning within a large angle range; therefore, it is necessary to compensate the corresponding piston phase of each OPA unit individually to achieve continuous scanning within a large angle range.

[0096] Fig.14 A schematic diagram of the principle of OPA unit compensation of piston phase is presented. The number of OPA units is at least 4. For a two-dimensional on-chip OPA array, the piston phase that needs to be compensated for a certain OPA unit is expressed by the following formula:

[0097]

[0098] in is the wavelength emitted by the laser generator; , It is the coordinate of the geometric center of the OPA unit relative to the equivalent large-aperture geometric center of the OPA array. In the plane of the OPA array, the direction of the plane rectangular coordinate system established with the equivalent large-aperture geometric center of the OPA array as the origin is not fixed, and the Z axis is always perpendicular to the plane of the OPA array; It is the angle between the output direction vector of the OPA unit output light beam after being deflected by the super lens unit and the X-axis; It is the angle between the output direction vector of the OPA unit output light beam after being deflected by the super lens unit and the Z axis;

[0099] Fig.12 A schematic diagram of the principle structure of the phase measurement and compensation module is shown, including a laser generating device 1, an optical fiber beam splitter 2, an optical fiber amplifier 3, an integrated optical chip, a phase measurement chip 8, and a phase compensation chip 9; the integrated optical chip includes an optical fiber-waveguide coupler 4, an OPA unit 7, an on-chip thin-film lithium niobate phase modulator 5, and an on-chip photodetector 6; the laser generated by the laser generating device 1 is divided into N paths by the optical fiber beam splitter 2, and each path passes through the optical fiber amplifier 3 and then passes through the optical fiber-waveguide coupler 4 to enter the on-chip photodetector 6 of the integrated optical chip, and the laser passes through the on-chip thin-film lithium niobate phase modulator 5 and then is emitted from the OPA unit 7 on the integrated optical chip; a small part of each laser entering the integrated optical chip is separated and enters the phase measurement chip 8; after the phase difference between two adjacent laser paths is calculated by the phase measurement chip, the signal is output to the phase compensation chip 9; the phase compensation chip 9 outputs a control signal to the on-chip thin-film lithium niobate phase modulator 5 on the integrated optical chip to compensate for the phase difference.

[0100] In one embodiment of the present invention, the OPA array phase measurement and compensation module detects and calculates the phase difference of adjacent OPA main laser optical paths through a phase measurement chip using a phase shift measurement method, a frequency mixing method, etc.; the phase compensation chip uses a PID control algorithm, an SPGD algorithm, a hill climbing algorithm, a particle swarm optimization algorithm, etc. to output a control signal to a phase modulator on an integrated optical chip, so that the phase difference of adjacent OPA main laser optical paths is locked at a fixed value to compensate for the OPA array piston phase, thereby achieving large-angle continuous scanning;

[0101] The OPA array phase measurement compensation module can control the phase of each OPA unit individually, allowing it to have any phase shift of 0 to 2π radians with adjacent OPA units;

[0102] In summary, a two-dimensional scanning OPA system based on a superlens array can adjust the deflection angle of the outgoing light beam for any scanning angle of the OPA unit within a certain angle range by translating the corresponding superlens array and changing the relative position of the superlens array and the OPA, and the beam divergence angle is small. Both one-layer and two-layer double-sided superlenses can achieve good results. The system has few structural parts, small mass and volume, which meets the current requirements for small and lightweight optical devices, and is easy to integrate into detection equipment such as autonomous driving vehicles and security monitoring.

[0103] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A two-dimensional scanning OPA system based on a superlens array, characterized in that: The system includes: On-chip two-dimensional OPA array for outgoing beams; A superlens array is placed at intervals with the on-chip two-dimensional OPA array, and is used to receive the light beam emitted from the OPA and deflect the light beam; the superlens array is placed parallel to the OPA, and the superlens array units correspond to the OPA units one by one, and the distance between them is a preset lens focal length f; An OPA array phase measurement and compensation module is used to compensate for the piston phase of the OPA array to achieve continuous scanning of the outgoing light beam at a large angle; the OPA array phase measurement and compensation module can individually control the phase of each OPA unit, allowing it to have any phase shift of 0 to 2π radians with adjacent OPA units; the phase compensation chip in the phase measurement and compensation module adopts PID control algorithm, SPGD algorithm, hill climbing algorithm or particle swarm optimization algorithm to output a control signal to the phase modulator on the integrated optical chip, so that the phase difference of the adjacent OPA main laser light paths is locked at a fixed value to compensate for the OPA array piston phase, thereby achieving continuous scanning at a large angle.

2. A two-dimensional scanning OPA system based on a superlens array according to claim 1, characterized in that: The metalens array comprises one or two layers of double-sided metalens arrays.

3. A two-dimensional scanning OPA system based on a superlens array according to claim 2, characterized in that: The double-sided superlens array comprises a first nanostructure layer, a base layer, and a second nanostructure layer. The first nanostructure layer and the second nanostructure layer are respectively connected to the front and back surfaces of the base layer to achieve light beam deflection.

4. A two-dimensional scanning OPA system based on a superlens array according to claim 1, characterized in that: The super lens array can be translated relative to the OPA. For any scanning angle of the OPA unit within a set angle range, the corresponding super lens unit adjusts the deflection angle of the outgoing light beam through relative translation.

5. The two-dimensional scanning OPA system based on a superlens array according to claim 1, characterized in that: The OPA array phase measurement and compensation module includes a laser generating device, an optical fiber beam splitter, an optical fiber amplifier, an integrated optical chip, a phase measurement chip and a phase compensation chip; the integrated optical chip includes an optical fiber-waveguide coupler, an OPA unit, an on-chip thin-film lithium niobate phase modulator and an on-chip photodetector; the laser generated by the laser generating device is divided into N paths by the optical fiber beam splitter, and each path passes through the optical fiber amplifier and then enters the on-chip photodetector of the integrated optical chip through the optical fiber-waveguide coupler, and the laser passes through the on-chip thin-film lithium niobate phase modulator and then is emitted from the OPA unit on the integrated optical chip; a small part of each laser entering the integrated optical chip is separated and enters the phase measurement chip; the phase measurement chip calculates the phase difference between two adjacent laser paths and outputs the signal to the phase compensation chip; the phase compensation chip outputs a control signal to the on-chip thin-film lithium niobate phase modulator on the integrated optical chip to compensate for the phase difference.

6. A two-dimensional scanning OPA system based on a superlens array according to claim 5, characterized in that: The OPA array phase measurement chip detects and calculates the phase difference of adjacent OPA main laser light paths through a phase shift measurement method or a frequency mixing method.

7. A two-dimensional scanning OPA system based on a superlens array according to claim 4, characterized in that: The metalens unit deflects all the OPA unit outgoing light beams within the divergence angle range to the same outgoing angle at the same relative translation amount.

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