View field angle adjustable amplification device and method of laser beam scanning system

Abstract

The invention discloses a field angle adjustable amplification device and method for a laser beam scanning system, and the device comprises a laser transmitter which is used for enabling a collimated laser beam to enter a reflection part; the reflecting piece reflects the incident laser beam and then the reflected laser beam enters the positive focal length lens; the positive focal length lens is used for condensing the incident light beams and then enabling the light beams to enter the scanning piece; the scanning piece is used for reflecting the converged laser beams into the negative focal length plano-concave lens at different angles after rotation; the negative focal length plano-concave lens is used for collecting the incident light and amplifying the angle of the emergent light beam; the distance between the positive focal length lens and the scanning piece or the distance between the negative focal length plano-concave lens and the scanning piece is adjusted to change the amplification factor of the emergent beam angle; a refraction angle expansion and dynamic beam shrinkage structure can be adopted, the consistency of the full-view-field beam shrinkage proportion is ensured, the large-angle incidence aberration is remarkably restrained, and the beam quality is improved; based on multi-wavelength chromatic aberration correction, dispersion is eliminated while the system structure is simplified.

Description

Technical Field

[0001] The present invention relates to the technical field of laser beam scanning, and in particular to a device and method for adjusting the field angle of view of a laser beam scanning system. Background Art

[0002] Laser beam scanning (LBS) technology uses two-dimensional scanners to precisely control the direction of laser beam reflection, and has achieved three-dimensional measurement and high-resolution imaging in fields such as lidar and projection display. However, its scanning angle is limited by the physical properties and manufacturing process of the scanner: large-angle incidence will cause the system size to expand, the coating reflectivity to decrease, and the aberration distortion to increase. Increasing the mirror size to accommodate large-angle requirements will reduce the mechanical resonance frequency, increase the driving complexity, and shorten the device life.

[0003] To break through this bottleneck, the existing technology adopts a solution of configuring an optical angle expansion device at the rear end of the scanning piece, such as a double positive lens combination based on the Kepler telescope principle (i.e., Chinese patent CN201811106003.8) or a positive and negative lens group of the Galilean double telecentric system (i.e., Chinese patent CN202111021783.8). Both of them achieve the magnification of the scanning angle through the beam reduction effect, and the angle expansion ratio is determined by the focal length ratio of the lens.

[0004] However, this type of design has inherent defects: after angle expansion, the laser divergence angle increases linearly with the original scanning angle, resulting in a significant deterioration of the beam quality in the edge field of view, and the need to rely on multiple lens groups to correct aberrations, which greatly increases the complexity and volume of the system; at the same time, the long focal length requirement forces the lens size and the overall optical path length to increase, making it difficult to adapt to compact equipment; in addition, the angle expansion ratio is fixed by the lens parameters and cannot be dynamically adjusted according to the application scenario, which limits the flexibility of the equipment. Summary of the Invention

[0005] The object of the present invention is to provide a device and method for adjusting the field angle of view of a laser beam scanning system, thereby solving all or one of the above problems in the prior art.

[0006] In order to solve the above technical problems, the specific technical solutions of the present invention are as follows: In one aspect, the present invention provides a device for adjusting the field angle of view of a laser beam scanning system, comprising: Laser emitter, reflector, positive focal length lens, scanner and negative focal length plano-concave lens; The laser emitter is used to generate a collimated laser beam and direct the collimated laser beam into the reflector; The reflector is located in front of the laser emitter; the reflector is used to fold the light path, reflecting the incident laser beam and then incident on the positive focal length lens; The positive focal length lens is located in front of the entrance pupil of the reflector and is arranged at an obliquely upper position of the reflector; the positive focal length lens is used to converge the incident light beam and then make it incident on the scanning element; The scanning element is located obliquely above the positive focal length lens and is used to reflect the converged laser beam into the negative focal length plano-concave lens at different angles after rotation; The negative focal length plano-concave lens is located behind the exit pupil of the scanning piece and is arranged on one side of the scanning piece; the negative focal length plano-concave lens is used to collect incident light and magnify the angle of the outgoing light beam; the positive focal length lens is used to adjust the distance between the positive focal length lens and the scanning piece to change the magnification of the outgoing light beam angle; the negative focal length plano-concave lens is used to adjust the distance between the negative focal length plano-concave lens and the scanning piece to change the magnification of the outgoing light beam angle.

[0007] As an improved solution, the positive focal length lens includes: a spherical lens and an aspherical lens; The positive focal length lens is further configured to: converge the incident light beam and direct the incident light beam into the scanning component in a converged state; The main optical axis of the positive focal length lens coincides with the rotation center point of the scanning component.

[0008] As an improved solution, the lens of the scanning piece is provided with a reflective film; The scanning part adopts a two-dimensional MEMS galvanometer.

[0009] As an improved solution, the concave surface of the negative focal length plano-concave lens is arranged to face the scanning piece; The main optical axis of the negative focal length plano-concave lens coincides with the rotation center of the scanning component.

[0010] As an improved solution, the positive focal length lens and the negative focal length plano-concave lens are arranged in a complementary manner; The absolute value of the focal length of the positive focal length lens is greater than the absolute value of the focal length of the negative focal length plano-concave lens; When the positive focal length lens needs to meet the system space requirements, if the laser beam is in a single wavelength state, the optical path between the positive focal length lens and the negative focal length plano-concave lens satisfies the sum of the focal lengths; When the positive focal length lens needs to meet the system space requirements, if the laser beam is in a single-wavelength multi-wavelength beam combination state, the optical path between the positive focal length lens and the negative focal length plano-concave lens satisfies the sum of the focal lengths, and the positive focal length lens and the negative focal length plano-concave lens satisfy the principle of chromatic aberration complementarity.

[0011] As an improved solution, the single-wavelength state includes: the wavelengths of the multiple laser beams are the same; the multi-wavelength combined beam state includes: the wavelengths of the multiple laser beams are different.

[0012] As an improved solution, the color difference complementary principle includes: At each wavelength, the sum of the focal lengths of the positive focal length lens (301) and the negative focal length plano-concave lens (302) is equal; or, At each wavelength, the absolute value of the difference between the sums of the focal lengths corresponding to any two wavelengths is not greater than a first threshold.

[0013] As an improved solution, the negative focal length plano-concave lens is further used to adjust the field of view magnification by adjusting the distance between the negative focal length plano-concave lens and the scanning component.

[0014] As an improved solution, the scanning component is further used to achieve multi-wavelength laser scanning amplitude alignment based on a MEMS scanning galvanometer.

[0015] As an improved solution, the laser beam generated by the laser transmitter includes: a single-wavelength collimated laser beam and laser beams of multiple wavelengths collimated and combined by the laser; The optical axis directions of the laser beams of various wavelengths in the combined laser beam are consistent, and the optical axis of the laser beam is consistent with the optical axis of the positive focal length lens.

[0016] On the other hand, the present invention also provides a method for adjusting and magnifying the field angle of a laser beam scanning system, comprising the following steps: Calling a laser transmitter to generate a collimated laser beam, and directing the collimated laser beam into a reflective element; The reflector is used to fold the optical path, and the incident laser beam is reflected and then enters the positive focal length lens; A positive focal length lens is used to converge the incident light beam and then project it onto the scanned object; The scanning piece is called to reflect the converged laser beam at different angles into the negative focal length plano-concave lens after rotation; the negative focal length plano-concave lens is called to collect the incident light and magnify the angle of the outgoing light beam; during the magnification process, the magnification of the outgoing light beam angle is changed by adjusting the distance between the positive focal length lens and the scanning piece; and the magnification of the outgoing light beam angle is changed by adjusting the distance between the negative focal length plano-concave lens and the scanning piece.

[0017] The beneficial effects of the technical solution of the present invention are as follows: the present invention adopts a refractive angle expansion and dynamic beam reduction structure to ensure the consistency of the beam reduction ratio of the entire field of view, significantly suppresses large-angle incident aberrations, and improves the beam quality; based on multi-wavelength chromatic aberration correction, it eliminates dispersion while simplifying the system structure, greatly reducing the back-end space requirements; the present invention also decouples the relationship between the focal length ratio of the front and rear mirror groups and the magnification ratio, and ultimately realizes dynamic adjustment of the field of view angle, taking into account low cost, miniaturization and high image quality; it breaks through the performance bottleneck of traditional LBS systems and provides a high-precision, high-flexibility compact solution for laser scanning applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 2 is a schematic structural diagram of the field angle adjustable magnifying device of the laser beam scanning system according to Example 1 of the present invention; Figure 2 2 is a schematic structural diagram of the adjustable field angle magnifying device of the laser beam scanning system according to Example 1 of the present invention in a basic expanded angle state; Figure 3 2 is a schematic structural diagram of the adjustable field angle magnification device of the laser beam scanning system according to Example 1 of the present invention in a state where the angle magnification is reduced; Figure 4 2. It is a schematic structural diagram of the adjustable field angle magnification device of the laser beam scanning system according to Example 1 of the present invention in a state where the angle magnification is increased; Figure 5 Schematic diagram of the dispersion phenomenon of the field angle adjustable amplifying device of the laser beam scanning system according to Example 1 of the present invention; Figure 6 2 is a flow chart of a method for adjustable magnification of the field angle of view of a laser beam scanning system according to embodiment 2 of the present invention; The symbols in the accompanying drawings are described as follows: 100, laser emitter; 101, reflector; 102, scanner; 201, laser beam emitted from laser emitter; 202, laser beam emitted after scanner; 203, laser beam emitted after angle expansion; 301, positive focal length lens; 302, negative focal length plano-concave lens. DETAILED DESCRIPTION

[0020] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more precise definition of the protection scope of the present invention.

[0021] In the description of the present invention, it should be noted that the embodiments described in the present invention are only part of the embodiments of the present invention, rather than all of the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection of the present invention.

[0022] The terms "first," "second," and the like in the specification and claims herein and in the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate so that the embodiments of the present invention described herein can be implemented in orders other than those illustrated or described herein. In addition, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product, or device comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0023] 1. MEMS (Micro-electro Mechanical Systems) is a micro-electromechanical system, specifically referring to micro-electronic mechanical systems, microsystems, micromachines, etc., referring to high-tech devices with a size of several millimeters or even smaller.

[0024] 2. LBS (Laser Beam Scanning) refers to laser beam scanning, which specifically refers to a technical solution that uses reflection from the scanning piece to scan the laser beam point by point in space.

[0025] Example 1: This embodiment provides a device for adjusting the viewing angle of a laser beam scanning system. Figures 1 to 5 As shown, including: (1) A laser emitter 100, which is used to generate a collimated laser beam that enters the reflector 101 and then enters the positive focal length lens 301 after being reflected; Specifically, the laser beam generated by the laser transmitter 100 includes, but is not limited to: a collimated laser beam of a single wavelength and a laser beam of multiple wavelengths after being collimated and combined by a laser; Specifically, the optical axes of the laser beams of various wavelengths in the combined laser beam are in the same direction; the optical axis of the laser beam is consistent with the optical axis of the positive focal length lens 301 , ie, vertical incidence.

[0026] (2) A positive focal length lens 301, located in front of the entrance pupil of the reflective scanning element 102, which includes a spherical lens and an aspherical lens; the positive focal length lens 301 is used to converge the light beam, and the laser beam passes through the positive focal length lens 301 and enters the scanning element 102 in a converged state, and its main optical axis coincides with the rotation center of the scanning element 102; Specifically, the positive focal length lens 301 and the negative focal length plano-concave lens 302 are arranged in a complementary manner, and the following conditions are met: A. Setting the absolute value of the focal length of the positive focal length lens 301 to be greater than the absolute value of the focal length of the negative focal length lens; B. If the laser beam is in a single-wavelength state (i.e., multiple laser beams have the same wavelength), the positive focal length lens 301 must meet the system space requirements, and the optical path between the positive focal length lens 301 and the negative focal length plano-concave lens 302 must meet the sum of the focal lengths; C. If the laser beam is in a multi-wavelength combined state (i.e., the wavelengths of the multiple laser beams are different), then while satisfying condition B, the positive focal length lens 301 and the negative focal length lens must satisfy the principle of chromatic aberration complementarity (at each wavelength, the sum of the focal lengths of the two lenses is equal or close). The meaning of close is further explained here, that is, at each wavelength, the absolute value of the difference between the sum of the focal lengths of the two lenses corresponding to any two wavelengths (because the difference may be negative, the absolute value is required for comparison) is not greater than a preset first threshold, which can be set according to the specific situation, such as 1 micron.

[0027] (3) Reflector 101, used for folding the light path.

[0028] (4) Scanning part 102, with a reflective film, uses a two-dimensional MEMS galvanometer mirror to reflect the converged laser beam into the plano-concave lens at different angles after rotation.

[0029] (5) A negative focal length plano-concave lens 302 is located behind the exit pupil of the scanning piece 102, with its concave surface facing the scanning piece 102, and its optical axis coincides with the rotation center of the scanning piece 102; the negative focal length plano-concave lens 302 is used to collect incident light, thereby amplifying the angle of the outgoing light beam, and adjusting the distance between the positive focal length lens 301 and the scanning piece 102 and the distance between the negative focal length plano-concave lens 302 and the scanning piece 102, thereby achieving a change in the magnification ratio of the outgoing light beam angle; Specifically, based on the focal length of the negative focal length plano-concave lens 302 meeting the above conditions, the concave surface of the negative focal length plano-concave lens 302 re-collimates the incident convergent light beam, and the laser beam emerges from the plane; Specifically, when the negative focal length plano-concave lens 302 of the present device is translated along the optical axis, and the positive focal length lens 301 is also translated along the optical axis, the optical path remains unchanged; when the negative focal length plano-concave lens 302 approaches the scanned object 102, the angle expansion magnification decreases; when the negative focal length plano-concave lens 302 moves away from the scanned object 102, the angle expansion magnification increases; within the allowable range of the divergence angle of the outgoing light beam, the adjustable magnification of the field angle can be achieved in the above manner; to better illustrate the principle of the present device, the above technical effects are verified based on the following calculation process: (i) Define the focal length of the positive focal length lens 301 as F1, the absolute value of the focal length of the negative focal length plano-concave lens 302 as F2, the spherical radius of the negative focal length plano-concave lens 302 as R, the distance from the positive focal length lens 301 to the scanned object 102 as D1, and the distance from the negative focal length plano-concave lens 302 to the scanned object 102 as D2. Then, for the present adjustable angle expansion magnification device, its basic angle expansion state is: when the spherical center of the plano-concave lens coincides with the rotation center of the scanned object 102, D2 = R, and at this time , as Figure 2 ; Let the refractive index of the material of the plano-concave lens be n, n > 1; Let the original scanned field half-angle of the scanned object 102 be ; In this state, the optical axis of the laser beam is perpendicularly incident on the spherical surface, and within the lens, it is also incident on the plane at , and after refraction on the plane, it exits. The magnified field half-angle is:

[0030] The angle expansion magnification ratio α is:

[0031] The laser beam beam reduction ratio β is:

[0032] Among them, the angle expansion magnification ratio only depends on the refractive index of the material of the negative focal length plano-concave lens 302, and currently all field angles are perpendicularly incident on the plano-concave spherical lens. When the ratio of the laser beam width to the spherical radius is small, it can be regarded as a paraxial beam, with only a small spherical aberration, and the outgoing laser beams of all fields maintain consistency and excellent aberration at the same time.

[0033] (ii) For the present angle expansion adjustable magnification device, its state of reducing the angle expansion magnification is: the optical axis of the plano-concave lens coincides with the rotation center of the scanned object 102, and the distance between the two is less than the spherical radius value, that is: D2 < R, and at this time , the optical path of the lens group remains unchanged, as Figure 3 ; In this state, the optical axis of the laser beam is not perpendicularly incident on the spherical surface, and it refracts within the lens and enters the lens plane at an angle , then there is:

[0034] Based on formula (4), we can know that the material refractive index n is greater than 1, Less than , at this time the half angle of the field of view of the light beam emitted from the lens plane for:

[0035] Based on formula (5), we can know that Less than , to achieve a reduction in magnification, at which point there is partial aberration in the outer edge field of view.

[0036] (iii) For the present angle-adjustable magnifying device, the state in which the angle-adjustable magnifying ratio is increased is: the optical axis of the plano-concave lens coincides with the rotation center of the scanning element 102, and the distance between the two is greater than the spherical radius, that is, D2>R. , the optical path of the lens group remains unchanged, such as Figure 4 In this state, the laser beam axis is not perpendicular to the spherical surface and is refracted in the lens at an angle of The incident lens plane has:

[0037] Based on formula (6), we can know that the material refractive index n is greater than 1, Greater than , at this time the half angle of the field of view of the light beam emitted from the lens plane for:

[0038] Based on formula (7), we can know that Greater than , to increase the magnification, at this time there is some aberration in the outer edge field of view.

[0039] Based on (i) to (iii), it can be seen that by changing the distance between the negative focal length plano-concave lens 302 and the scanning element 102 when the lens is translated along the optical axis, dynamic adjustment of the field of view magnification can be achieved.

[0040] Specifically, the multi-wavelength laser scanning amplitude alignment is achieved based on the MEMS scanning galvanometer, as follows: Due to the dispersion of the material, the refractive index of the material at different wavelengths Different, from formula (1), we can see that the field angle magnification of different wavelengths is different, resulting in dispersion phenomenon, such as Figure 5 , then the half angle of the field of view of each wavelength after the expansion is for:

[0041] Based on the characteristic of continuous scanning of the MEMS scanning galvanometer in space, the lighting timing of laser beams of different wavelengths is modulated to achieve the alignment of the emission angles of multiple beams, that is, the alignment of the multi-wavelength laser scanning amplitude.

[0042] It should be noted that the above examples are only for explaining the present invention and are not intended to limit the scope of protection of the present invention.

[0043] Example 2: This example is based on the same inventive concept as the device for adjusting the field angle of a laser beam scanning system described in Example 1, and provides a method for adjusting the field angle of a laser beam scanning system. Figure 6 As shown, the following steps are included: S100, calling a laser transmitter to generate a collimated laser beam, and directing the collimated laser beam into a reflective element; S200, calling a reflector to fold the optical path, reflecting the incident laser beam and then causing it to enter a positive focal length lens; S300, calling a positive focal length lens to condense the incident light beam and then inject it into the scanned object; S400, calling the scanning piece to reflect the converged laser beam at different angles into the negative focal length plano-concave lens after rotation; calling the negative focal length plano-concave lens to collect the incident light and magnify the angle of the outgoing light beam; during the magnification process, changing the magnification of the outgoing light beam angle by adjusting the distance between the positive focal length lens and the scanning piece; changing the magnification of the outgoing light beam angle by adjusting the distance between the negative focal length plano-concave lens and the scanning piece.

[0044] Different from the existing technology, the field of view angle adjustable magnification device and method of the laser beam scanning system of the present application can adopt the refractive expansion angle and dynamic beam reduction structure to ensure the consistency of the beam reduction ratio of the entire field of view, significantly suppress the aberration of large-angle incidence, and improve the beam quality; based on multi-wavelength chromatic aberration correction, it eliminates dispersion while simplifying the system structure, and greatly reduces the back-end space requirements; the present invention also decouples the relationship between the focal length ratio of the front and rear mirror groups and the magnification ratio, and ultimately realizes dynamic adjustment of the field of view angle, taking into account low cost, miniaturization and high image quality; breaking through the performance bottleneck of traditional LBS systems, and providing a high-precision, high-flexibility compact solution for laser scanning applications.

[0045] It should be understood that in the various embodiments of this document, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this document.

[0046] It should also be understood that in the embodiments herein, the term "and / or" merely describes an association between associated objects, indicating that three possible relationships exist. For example, "A and / or B" could represent: A alone, A and B simultaneously, or B alone. Furthermore, the character " / " in this document generally indicates an "or" relationship between the associated objects.

[0047] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the composition and steps of each example according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this document.

[0048] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the method process described above may refer to the specific working processes of the corresponding systems, devices and units in the aforementioned method embodiments, which will not be repeated here.

[0049] In the several embodiments provided herein, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices, or units, or can be an electrical, mechanical, or other form of connection.

[0050] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments herein.

[0051] In addition, the functional units in the various embodiments herein may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0052] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this article is essentially or the part that contributes to the existing technology, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of this article. The aforementioned storage medium includes: various media that can store program code, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0053] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention's description and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A field angle adjustable magnifying device for a laser beam scanning system, characterized in that: include: A laser emitter (100), a reflector (101), a positive focal length lens (301), a scanning element (102), and a negative focal length plano-concave lens (302); The laser emitter (100) is used to generate a collimated laser beam, and to direct the collimated laser beam into the reflector (101); The reflector (101) is located directly in front of the laser emitter (100); the reflector (101) is used to fold the light path, reflecting the incident laser beam and then causing it to enter the positive focal length lens (301); The positive focal length lens (301) is located in front of the entrance pupil of the reflector (101) and is arranged at a position obliquely above the reflector (101); the positive focal length lens (301) is used to converge the incident light beam and then cause it to enter the scanning element (102); The scanning element (102) is located obliquely above the positive focal length lens (301) and is used to reflect the converged laser beam at different angles into the negative focal length plano-concave lens (302) after rotation; The negative focal length plano-concave lens (302) is located behind the exit pupil of the scanning piece (102) and is arranged at a side of the scanning piece (102); the negative focal length plano-concave lens (302) is used to collect incident light and magnify the angle of the outgoing light beam; the positive focal length lens (301) is used to adjust the distance between the positive focal length lens (301) and the scanning piece (102) to change the magnification of the angle of the outgoing light beam; the negative focal length plano-concave lens (302) is used to adjust the distance between the negative focal length plano-concave lens (302) and the scanning piece (102) to change the magnification of the angle of the outgoing light beam.

2. The field angle adjustable magnifying device of the laser beam scanning system according to claim 1, characterized in that: The positive focal length lens (301) comprises: a spherical lens and an aspherical lens; The positive focal length lens (301) is further specifically used to: converge the incident light beam, and direct the incident light beam into the scanning component (102) in a converged state; The main optical axis of the positive focal length lens (301) coincides with the rotation center point of the scanning component (102).

3. The field angle adjustable magnifying device of the laser beam scanning system according to claim 1, characterized in that: The lens of the scanning part (102) is provided with a reflective film; The scanning part (102) adopts a two-dimensional MEMS oscillating mirror.

4. The field angle adjustable magnifying device of the laser beam scanning system according to claim 1, characterized in that: The concave surface of the negative focal length plano-concave lens (302) is arranged facing the scanning part (102); The main optical axis of the negative focal length plano-concave lens (302) coincides with the rotation center of the scanning part (102).

5. The field angle adjustable magnifying device of the laser beam scanning system according to claim 1, characterized in that: The positive focal length lens (301) and the negative focal length plano-concave lens (302) are arranged in a complementary manner; The absolute value of the focal length of the positive focal length lens (301) is greater than the absolute value of the focal length of the negative focal length plano-concave lens (302); When the positive focal length lens (301) needs to meet the system space requirement, if the laser beam is in a single wavelength state, the optical path between the positive focal length lens (301) and the negative focal length plano-concave lens (302) satisfies the sum of the focal lengths; When the positive focal length lens (301) needs to meet the system space requirements, if the laser beam is in a multi-wavelength beam combining state, the optical path between the positive focal length lens (301) and the negative focal length plano-concave lens (302) satisfies the sum of the focal lengths, and the positive focal length lens (301) and the negative focal length plano-concave lens (302) satisfy the principle of chromatic aberration complementarity.

6. The field angle adjustable magnifying device of the laser beam scanning system according to claim 5, characterized in that: The single wavelength state includes: the wavelengths of the multiple laser beams are the same; The multi-wavelength beam combining state includes: the wavelengths of the multiple laser beams are different.

7. The field angle adjustable magnifying device of the laser beam scanning system according to claim 5, characterized in that: The color difference complementary principle includes: At each wavelength, the sum of the focal lengths of the positive focal length lens (301) and the negative focal length plano-concave lens (302) is equal; or, At each wavelength, the absolute value of the difference between the sums of the focal lengths corresponding to any two wavelengths is not greater than a first threshold.

8. The field angle adjustable magnifying device of the laser beam scanning system according to claim 5, characterized in that: The negative focal length plano-concave lens (302) is further specifically used to adjust the field of view angle magnification by adjusting the distance between the negative focal length plano-concave lens (302) and the scanning piece (102); The scanning component (102) is further specifically used to achieve multi-wavelength laser scanning amplitude alignment based on a MEMS scanning galvanometer.

9. The field angle adjustable magnifying device of the laser beam scanning system according to claim 1, characterized in that: The laser beam generated by the laser emitter (100) includes: a single-wavelength collimated laser beam and laser beams of multiple wavelengths collimated and combined by a laser; The optical axis directions of the laser beams of each wavelength in the combined laser beam are consistent, and the optical axis of the laser beam is consistent with the optical axis of the positive focal length lens (301).

10. A method for adjusting the field angle of view and magnifying the device for adjusting the field angle of view and magnifying the laser beam scanning system according to any one of claims 1 to 9, characterized in that: The method comprises the following steps: Calling a laser transmitter to generate a collimated laser beam, and directing the collimated laser beam into a reflective element; The reflector is used to fold the optical path, and the incident laser beam is reflected and then enters the positive focal length lens; A positive focal length lens is used to converge the incident light beam and then project it onto the scanned object; The scanning piece is called to reflect the converged laser beam at different angles into the negative focal length plano-concave lens after rotation; the negative focal length plano-concave lens is called to collect the incident light and magnify the angle of the outgoing light beam; during the magnification process, the magnification of the outgoing light beam angle is changed by adjusting the distance between the positive focal length lens and the scanning piece; and the magnification of the outgoing light beam angle is changed by adjusting the distance between the negative focal length plano-concave lens and the scanning piece.

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