Reflective beam shaping method and shaping mirror insensitive to light source and capable of generating multiple focuses

Abstract

The invention belongs to the technical field of laser processing, and discloses a reflective beam shaping method insensitive to a light source and capable of generating multiple focuses and a shaping mirror, and the method comprises the steps: pre-dividing a reflecting surface of a reflective beam shaping mirror into a plurality of sub-reflecting surfaces; wherein after the light source enters each sub-reflecting surface, a plurality of target focuses are formed at preset positions of the working surface; constructing a mapping relation between each sub-reflecting surface and the target focus; and determining a surface type function of each sub-reflecting surface according to an initial surface type equation of the sub-reflecting surfaces and the mapping relation, and calculating an accurate analytical solution of boundaries of all adjacent sub-reflecting surfaces so as to ensure the continuity of the whole surface type. Multi-focus beam shaping can be achieved only through one reflecting mirror, optical elements are few, an integral form is adopted, the device is not sensitive to an incident light source and is not affected by light source fluctuation, more ideal and stable effects can be achieved, and the device can be widely applied to laser machining scenes such as laser cutting and laser welding.

Description

Technical Field

[0001] The present invention belongs to the field of laser processing technology, and more specifically, relates to a reflective beam shaping method and shaping mirror for generating multiple focal points that are insensitive to light sources. Background Art

[0002] In the field of industrial processing, 10,000-watt lasers are widely used in automobile manufacturing, shipbuilding, aircraft manufacturing, etc. In the face of high-power laser cutting and welding applications, beam shaping is becoming more and more common in achieving high-quality laser processing. Studies have shown that transverse or axial beam shaping to achieve multi-focus can significantly improve the stability of the laser processing process. Beam shaping optimizes the energy distribution of the laser spot and improves the balance of keyhole formation in laser processing, thereby improving the stability and forming quality of the laser processing process.

[0003] However, the laser output of high-power lasers often has non-ideal beam characteristics, such as poor beam quality and the presence of pattern noise. The conventional method for generating multiple focal points generally uses the field mapping method. Since there is a one-to-one mapping relationship between the incident light and the target focus in the field mapping method, the field mapping method is sensitive to the input light source and cannot fully guarantee the energy uniformity of each focus. Summary of the Invention

[0004] In response to the above defects or improvement needs of the prior art, the present invention provides a reflective beam shaping method and shaping mirror for generating multiple focal points that are insensitive to the light source. The purpose is to make the generated light spot insensitive to the input light source and improve the uniformity of the light spot energy to achieve high-quality laser cutting and welding process requirements.

[0005] To achieve the above objectives, the present invention provides a method for designing a reflective beam shaping mirror that is insensitive to light sources and generates multiple focal points, comprising:

[0006] The reflective surface of the reflective beam shaping mirror is pre-divided into a plurality of sub-reflective surfaces; wherein, after the light source is incident on each sub-reflective surface, a plurality of target focal points are formed at preset positions on the working surface, all the target focal points form a target focal point array A, and a plurality of adjacent sub-reflective surfaces form a reflective surface array B;

[0007] Constructing a mapping relationship between each sub-reflecting surface and the target focus, wherein the mapping relationship is: the number and position of each sub-reflecting surface in the reflecting surface array B respectively correspond to the number and position of the target focus in the target focus array A;

[0008] The surface shape function of each sub-reflecting surface is determined according to the initial surface shape equation of the sub-reflecting surface and the mapping relationship, thereby obtaining a designed reflective beam shaping mirror; wherein, when the light source is a collimated incident light source, the initial surface shape of each sub-reflecting surface is a parabola; when the light source is an ideal point light source, the initial surface shape of each sub-reflecting surface is an ellipsoid.

[0009] Furthermore, the surface function of each sub-reflecting surface is determined according to the initial surface equation of the sub-reflecting surface and the mapping relationship to obtain a designed reflective beam shaping mirror, including:

[0010] Establishing a spatial rectangular coordinate system with the center of the reflecting surface as the coordinate system zero point O(0,0,0), and taking the sub-reflecting surface passing through the coordinate system zero point O(0,0,0) as the central sub-reflecting surface;

[0011] For the current sub-reflector, based on the determined surface function of the sub-reflector F* adjacent to the current sub-reflector, the coordinates of the intersection of the sub-reflector F* and the current sub-reflector are calculated, and the intersection coordinates and the target focus coordinates corresponding to the current sub-reflector are substituted into the initial surface equation of the sub-reflector to determine the surface function of the current sub-reflector; initially, the surface function of the central sub-reflector is first determined, and its surface function is determined by substituting the zero point O(0, 0, 0) of the coordinate system and the target focus coordinates corresponding to the central sub-reflector into the initial surface equation of the sub-reflector; wherein, the target focus coordinates corresponding to each sub-reflector are determined based on the mapping relationship.

[0012] Furthermore, when the light source is a collimated incident light source, the initial surface equation of the sub-reflecting surface is a parabolic surface equation:

[0013]

[0014] Where (x, y, z) is the three-dimensional coordinate of the parabola equation, F(x F ,y F ,z F ) is the target focus corresponding to the sub-reflection surface, D(x D ,y D ,z D ) is the vertex of the parabola equation, and x D =x F ,y D =y F ; The xoy plane of the spatial rectangular coordinate system is a plane perpendicular to the incident light, and the incident direction of the light is the negative direction of the z axis;

[0015] The surface shape function of the central sub-reflecting surface is determined by substituting the coordinate system zero point O(0, 0, 0) and the target focus coordinates corresponding to the central sub-reflecting surface into the initial surface shape equation of the sub-reflecting surface, including:

[0016] The coordinate system zero point O(0, 0, 0) and the target focus coordinate F(x F ,y F ,z F ) into the parabolic surface equation, we get z D , and then the surface function of the central sub-reflection surface is obtained:

[0017] Furthermore, the method further includes determining the boundary shapes of two adjacent sub-reflection surfaces, specifically including:

[0018] By making the surface functions of two adjacent sub-reflecting surfaces equal, an accurate analytical solution of the boundaries of the two adjacent sub-reflecting surfaces is obtained, and the accurate analytical solution constitutes the boundary shape of the two adjacent sub-reflecting surfaces.

[0019] Furthermore, the reflective surface of the reflective beam shaping mirror is pre-divided into a plurality of sub-reflective surfaces according to the number, position, and energy distribution of the target focal points in the target focal point array A; wherein the energy distribution is used to determine the area of ​​each sub-reflective surface, and the ratio of the area of ​​each sub-reflective surface in the reflective surface array B is proportional to the ratio of the energy value of each corresponding focal point in the target focal point array A. The number and position are used to determine the pre-division method, and the pre-division method includes:

[0020] When the target focus array A is distributed in M*N horizontal and vertical directions, the reflecting surface is divided horizontally and vertically; wherein M>1, N>1;

[0021] When the target focus array A is distributed in a 1*N horizontal pattern or in an M*1 vertical pattern, the reflection surface is correspondingly divided into horizontal or vertical rows;

[0022] When the target focus array A is axially distributed along the light propagation direction, the reflecting surface is divided into annular parts.

[0023] Furthermore, when the energy distribution of each target focus in the target focus array A is the same, the areas of each sub-reflection surface divided horizontally and vertically and divided in an annular manner are the same, and the distances of each sub-reflection surface divided in horizontal or vertical columns along the dividing direction are equal.

[0024] The present invention also provides a reflective beam shaping mirror that is insensitive to light sources and generates multiple focuses, comprising a reflective surface, wherein the reflective surface is designed using any of the above-mentioned methods for designing a reflective beam shaping mirror that generates multiple focuses.

[0025] Furthermore, it also includes a cylindrical base, and the reflecting surface is arranged on the cylindrical base.

[0026] The present invention also provides a reflective beam shaping system for generating multiple focal points that is insensitive to light sources, comprising: a light source and a reflective beam shaping mirror;

[0027] The reflective surface of the reflective beam shaping mirror is designed using any of the above-mentioned methods for designing a reflective beam shaping mirror for generating multiple focal points, or the reflective beam shaping mirror is the above-mentioned reflective beam shaping mirror.

[0028] Furthermore, the light source is a collimated incident light source, or an ideal point light source; when the light source is a collimated incident light source, the light source includes a laser and a parabolic collimator for collimating the light emitted by the laser.

[0029] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

[0030] (1) The reflective beam shaping mirror designed by the present invention for generating multiple focal points divides the reflective surface into several sub-reflective surfaces and constructs a mapping relationship between each sub-reflective surface and the target focus. Only one reflective mirror is needed to generate multiple target focuses, and the reflective mirror is insensitive to the input light source. Specifically, after the light source is incident on the reflective surface, the incident light is divided into different energy blocks, and the same target focus has a plurality of light spots in different regions (corresponding to different sub-reflective surfaces) superimposed, that is, the target focus is formed by the superposition of light spots in different regions. This form of beam integration ensures that the target focus formed is not affected by light source fluctuations and is insensitive to the input light source, thereby ensuring the energy uniformity of each focus, and can effectively improve the focal depth of the focused light spot and improve the processing quality. The present invention only requires one reflective mirror to achieve beam shaping, has fewer optical components, a streamlined optical path structure, and strong anti-interference ability.

[0031] (2) Furthermore, the boundary shape of the two adjacent sub-reflecting surfaces is determined by calculating the precise analytical solution of the two adjacent sub-reflecting surfaces, thereby ensuring the continuity of the entire reflective surface shape. The surface shape can be processed by an ultra-precision diamond lathe, which reduces the difficulty of surface processing and has practical application scenarios.

[0032] (3) Furthermore, the present invention can design the number, position and energy distribution of the required target focus, with a high degree of design freedom, including the design and generation of different types of target focus, such as quad-focus, lateral multi-focus, axial multi-focus, etc., thereby adapting to the needs of different scenarios in actual processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A reflective beam shaping mirror designed in an embodiment of the present invention that is insensitive to light sources and generates multiple focal points;

[0034] Figure 2 1 is a schematic structural diagram of an optical system for generating four-focal spot light provided in Example 1 of the present invention;

[0035] Figure 3 This is a schematic diagram of a simulation of generating a four-focus light spot provided in Example 1 of the present invention;

[0036] Figure 4 Schematic diagram of the structure of the optical system for generating a transverse trifocal spot provided by Example 2 of the present invention;

[0037] Figure 5 This is a schematic diagram of a simulation of generating a lateral trifocal spot provided by Example 2 of the present invention;

[0038] Figure 6 Schematic diagram of the structure of an optical system for generating axial two-focus light spots provided by Example 3 of the present invention;

[0039] Figure 7 This is a simulation diagram of generating axial two-focus light spots provided by Example 3 of the present invention.

[0040] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0041] 1-laser, 2-parabolic collimator, 3-reflective beam shaping mirror, 4-working surface, 5-reflecting mirror surface curvature, 6-first target focus, 7-second target focus, 31-reflecting surface, 32-base, 33-sub-reflecting surface, 34-boundary between adjacent sub-reflecting surfaces. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0043] In the present invention, the terms "first", "second", etc. in the present invention and the accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0044] Example 1

[0045] like Figure 1 As shown, an embodiment of the present invention provides a design method for a reflective beam shaping mirror that is insensitive to light sources and generates multiple focal points, wherein the reflective beam shaping mirror 3 includes: a cylindrical base 32 and a reflective surface 31 on the base. The design method includes:

[0046] The reflective surface 31 is pre-divided into a plurality of sub-reflective surfaces 33; wherein, after the light source is incident on each sub-reflective surface, a plurality of target focal points are formed at preset positions on the working surface, all target focal points form a target focal point array A, and a plurality of adjacent sub-reflective surfaces form a reflective surface array B;

[0047] A mapping relationship is established between each sub-reflecting surface and the target focal point so that the light reflected by each sub-reflecting surface can be focused to the preset target focal point on the working surface. This mapping relationship is as follows: the number and position of sub-reflecting surfaces in each reflective surface array B correspond to the number and position of target focal points in the target focal point array A. In the reflective surface array B, each sub-reflecting surface corresponds to a focal point, and its adjacent sub-reflecting surfaces correspond to adjacent target focal points.

[0048] The surface shape function of each sub-reflector is determined based on the initial surface shape equation of the sub-reflector and the mapping relationship between each sub-reflector and the target focus. When the light source is a collimated incident light source, the initial surface shape of the sub-reflector is a parabola; when the light source is an ideal point light source, the initial surface shape of the sub-reflector is an ellipsoid. The boundary 34 between adjacent sub-reflectors is irregular in shape. The boundary shape is calculated using the precise analytical solution of the two sub-reflectors adjacent to the boundary, including:

[0049] For a sub-reflector, the surface function is F1(x,y), and the surface function of the sub-reflector adjacent to the sub-reflector is F2(x,y). By solving F1(x,y)=F2(x,y), the precise analytical solution of the boundary where the two sub-reflectors intersect is calculated to ensure the continuity of the entire reflector surface and complete the design of the reflective beam shaping mirror.

[0050] As a specific implementation method, the surface function of each sub-reflecting surface is determined according to the initial surface equation of the sub-reflecting surface and the mapping relationship between each sub-reflecting surface and the target focus, including:

[0051] Establish a spatial rectangular coordinate system with the center of the reflecting surface as the coordinate system zero point O, take the sub-reflecting surface passing through the coordinate system zero point O as the central sub-reflecting surface, substitute the coordinate system zero point O (0, 0, 0) and the target focus coordinates corresponding to the central sub-reflecting surface into the initial surface equation of the sub-reflecting surface to determine the surface function of the central sub-reflecting surface; based on the determined surface function of the central sub-reflecting surface, calculate the relationship between the central sub-reflecting surface and its adjacent sub-reflecting surface F * The intersection coordinates of the sub-reflection surface F * The corresponding target focus coordinates are substituted into the initial surface equation of the sub-reflector to determine the sub-reflector F * Surface function; based on the determined sub-reflection surface F * Surface function, calculate the sub-reflection surface F *The surface function of each sub-reflecting surface is obtained by comparing the coordinates of the intersection points with the adjacent sub-reflecting surfaces and so on.

[0052] The target focus coordinates corresponding to each sub-reflecting surface are determined based on a mapping relationship between each sub-reflecting surface and the target focus.

[0053] For a collimated incident light source, the initial surface shape of each sub-reflecting surface is a parabola; for an ideal point light source, the initial surface shape of each sub-reflecting surface is an ellipsoid.

[0054] The following takes a collimated incident light source as an example to further illustrate the method for determining the surface shape function of each sub-reflecting surface in the embodiment of the present invention.

[0055] A spatial rectangular coordinate system is constructed with the incident direction of the light being the negative direction of the z-axis, that is, the light source being located in the positive direction of the z-axis, the center of the reflective surface being located at the zero point O of the coordinate system, and the xoy plane being a plane perpendicular to the incident light. In other embodiments, a corresponding spatial rectangular coordinate system can also be constructed according to actual conditions, ensuring that the zero point O of the coordinate system is the center of the reflective surface. Preferably, when the incident light is incident along the negative direction of the z-axis, the initial surface shape of the sub-reflective surface is a parabola, and the parabolic surface equation is:

[0056]

[0057] Among them, (x, y, z) are the three-dimensional coordinates of the parabola equation, and the focus of the parabola equation is F(x F ,y F ,z F ) and the vertex is D(x D ,y D ,z D ), F(x F ,y F ,z F ) is the target focus corresponding to the sub-reflection surface. Since the line connecting the incident light and the target focus and the vertex is parallel, x D =x F ,y D =y F For the central sub-reflector (the sub-reflector passing through the coordinate system zero point O), which passes through the center point (0, 0, 0), the z-axis coordinate z of the vertex D corresponding to the central sub-reflector can be obtained by substituting it into the parabolic surface equation. D , the surface function of the central sub-reflector can be expressed as follows:

[0058]

[0059] Among them, (x F ,y F ,z F ) is the target focus corresponding to the central sub-reflection surface.

[0060] Furthermore, by obtaining the surface function of the central sub-reflecting surface, the intersection point of the central sub-reflecting surface and the adjacent (adjacent) sub-reflecting surface can be obtained, and the intersection point and the target focus corresponding to the adjacent sub-reflecting surface are substituted into the parabolic surface equation to obtain the z-axis coordinate z of the vertex D corresponding to the adjacent sub-reflecting surface. D , get the surface function of the adjacent sub-reflecting surface, and so on, get the surface function of all sub-reflecting surfaces.

[0061] Furthermore, for a sub-reflector with a surface function of F1(x,y), its adjacent sub-reflector has a surface function of F2(x,y). By solving F1(x,y) = F2(x,y), we can calculate the exact analytical solution for the boundary where the two sub-reflectors intersect, thus ensuring the continuity of the entire surface shape. For the case of an ideal point light source, where each surface shape is an ellipsoid, the same method can be used to infer the same.

[0062] In an embodiment of the present invention, the reflective surface is pre-divided based on the number, location, and energy distribution of target focal points. The energy distribution is used to determine the area of ​​each sub-reflective surface. Specifically, the ratio of the energy values ​​of each focal point is directly proportional to the ratio of the areas of the pre-divided regions corresponding to the focal point through the aforementioned mapping relationship. That is, the area ratio of the sub-reflective surfaces in each reflective surface array B is directly proportional to the energy ratio of the corresponding focal points in the target focal point array A. Three pre-dividing methods are available: The first method involves a rectangular array of M*N targets, where M>1 and N>1, for example, four target focal points arranged in a 2*2 pattern. The reflective surface is divided horizontally and vertically, with each sub-region having a rectangular boundary. The second method involves a 1*N or M*1 array. In this case, the target focal points on the working surface are distributed horizontally or vertically, and the reflective surface is correspondingly divided into horizontal or vertical rows, with each sub-region having a strip-like shape. The third method involves an axial distribution of the target focal point array A along the light propagation direction, where the reflective surface is divided into an annular sub-region.

[0063] Example 2

[0064] An embodiment of the present invention provides a reflective beam shaping mirror that is insensitive to light sources and generates multiple focal points, comprising: a cylindrical base 32 and a reflective surface 31 on the base 32, wherein the reflective surface 31 is designed using the design method for a reflective beam shaping mirror that is insensitive to light sources and generates multiple focal points in the above-mentioned embodiment 1.

[0065] The relevant technical solutions are the same as above and will not be repeated here.

[0066] Example 3

[0067] An embodiment of the present invention provides a reflective beam shaping system that is insensitive to light sources and generates multiple focal points, including: a light source and a reflective beam shaping mirror 3; for a collimated incident light source, the light source includes a laser 1 and a parabolic collimator 2, the parabolic collimator 2 is used to collimate the light beam emitted by the laser 1, and the collimated light beam is incident on the reflective beam shaping mirror 3 to generate preset multiple target focal points on the working surface 4.

[0068] The reflective beam shaping mirror 3 is designed by the design method of the reflective beam shaping mirror that is insensitive to light source and generates multiple focuses in Example 1, or is the reflective beam shaping mirror that is insensitive to light source and generates multiple focuses in Example 2.

[0069] The relevant technical solutions are the same as above and will not be repeated here.

[0070] The technical solutions provided in the embodiments of the present invention are introduced below with specific examples. The light sources in Examples 1 to 3 are all collimated incident light sources.

[0071] Example 1

[0072] based on Figure 2 The illustrated optical system for generating a quadruple focal spot is designed with a working distance of 200mm, a spacing of 1mm between the four target focal points, and a target energy distribution requirement of equal energy at all four focal points (each pre-divided area is equal). Using the first partitioning method, the reflective surface is divided horizontally and vertically, with each sub-area being quasi-rectangular. Because the four focal points require equal energy, the areas of each sub-area are equal. Based on the design method described in Example 1 above, the surface function of each sub-reflective surface is obtained. The designed reflector surface curvature 5 shows an irregular boundary shape for each sub-reflective surface, calculated using an exact analytical solution.

[0073] Figure 3 The corresponding schematic diagram of the simulation of generating a four-focal spot includes a Gaussian spot with an incident Gaussian radius of 15 mm and a Gaussian spot with an offset incident Gaussian radius of 12 mm. At this time, the spots obtained on the working surface are all four-focal spots with the same energy distribution. When the energy position and size of the light source fluctuate, it can be found that this method can output a stable spot on the working surface.

[0074] Example 2

[0075] based on Figure 4 The optical system for generating a transverse trifocal spot is designed to have a working distance of 200 mm, a spacing of 1 mm between the three transverse target focal points, and equal energy distribution of the target focal points. The second division method is adopted, and the reflecting surface is divided into horizontal or vertical columns. Each sub-area is quasi-long strip-shaped. Since the energy distribution of the target focal points is equal, the distance between each sub-area along the division direction is equal. The method for generating the reflecting mirror surface is the same as that in Example 1.

[0076] The boundary of each sub-reflecting surface in the designed reflective mirror curvature 5 is irregular, in the form of a curved long strip, and its boundary is obtained by performing accurate analytical calculation with adjacent sub-reflecting surfaces.

[0077] Figure 5 The corresponding schematic diagram of the simulation of generating a transverse trifocal light spot includes a Gaussian light spot with an incident Gaussian radius of 15 mm and a Gaussian light spot with an offset incident Gaussian radius of 12 mm. At this time, the light spots obtained on the working surface are all transverse trifocal light spots with the same energy distribution. When the energy position and size of the light source fluctuate, it can be found that this method can output a stable light spot on the working surface.

[0078] Example 3

[0079] based on Figure 6 The axial two-focus spot reflector shown in the figure is designed with two target focal points with working distances of 200mm and 210mm. The target focal point energy distribution requirement is that the two focal points have the same energy. The third division method is adopted, and the reflecting surface is divided into rings. Each sub-area is a ring and has equal area. Each ring focuses the incident light spot to the corresponding focus. The reflective mirror surface generation method is the same as that in Example 1. Figure 6 As shown, different incident light rays emitted by laser 1 are split and shaped by reflective beam shaping mirror 3 (free-form surface reflector), with light rays from different regions focused onto different target focal points, including a first target focal point 6 and a second target focal point 7. Each sub-reflecting surface in the designed reflector surface curvature 5 is an irregular ring, and its boundary is calculated by accurately analyzing the adjacent sub-reflecting surfaces.

[0080] Figure 7 The following is a schematic diagram of the corresponding generated axial dual-focus spot simulation at different positions, including the spots at different working distances of 195mm, 200mm, 205mm, 210mm, and 215mm. It can be found that the spot is focused twice, at 200mm and 210mm respectively, and the center spot around 205mm is the strongest. It can be found that this axial beam control based on the integral form can ensure the same energy distribution of the two focal points, and can increase the focal depth, effectively improving the welding depth and cutting strength.

[0081] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for designing a reflective beam shaping mirror that is insensitive to light sources and generates multiple focal points, characterized in that: include: The reflective surface of the reflective beam shaping mirror is pre-divided into a plurality of sub-reflective surfaces; wherein, after the light source is incident on each sub-reflective surface, a plurality of target focal points are formed at preset positions on the working surface, all the target focal points form a target focal point array A, and a plurality of adjacent sub-reflective surfaces form a reflective surface array B; Constructing a mapping relationship between each sub-reflecting surface and the target focus, wherein the mapping relationship is: the number and position of each sub-reflecting surface in the reflecting surface array B respectively correspond to the number and position of the target focus in the target focus array A; The surface shape function of each sub-reflecting surface is determined according to the initial surface shape equation of the sub-reflecting surface and the mapping relationship, thereby obtaining a designed reflective beam shaping mirror; wherein, when the light source is a collimated incident light source, the initial surface shape of each sub-reflecting surface is a parabola; when the light source is an ideal point light source, the initial surface shape of each sub-reflecting surface is an ellipsoid.

2. The method for designing a reflective beam shaping mirror according to claim 1, wherein: The surface function of each sub-reflecting surface is determined according to the initial surface equation of the sub-reflecting surface and the mapping relationship to obtain a designed reflective beam shaping mirror, including: Establishing a spatial rectangular coordinate system with the center of the reflecting surface as the coordinate system zero point O(0,0,0), and taking the sub-reflecting surface passing through the coordinate system zero point O(0,0,0) as the central sub-reflecting surface; For the current sub-reflector, based on the determined surface function of the sub-reflector F* adjacent to the current sub-reflector, the coordinates of the intersection of the sub-reflector F* and the current sub-reflector are calculated, and the intersection coordinates and the target focus coordinates corresponding to the current sub-reflector are substituted into the initial surface equation of the sub-reflector to determine the surface function of the current sub-reflector; initially, the surface function of the central sub-reflector is first determined, and its surface function is determined by substituting the zero point O(0, 0, 0) of the coordinate system and the target focus coordinates corresponding to the central sub-reflector into the initial surface equation of the sub-reflector; wherein, the target focus coordinates corresponding to each sub-reflector are determined based on the mapping relationship.

3. The method for designing a reflective beam shaping mirror according to claim 2, wherein: When the light source is a collimated incident light source, the initial surface equation of the sub-reflecting surface is a parabolic surface equation: Where (x, y, z) is the three-dimensional coordinate of the parabola equation, F(x F ,y F ,z F ) is the target focus corresponding to the sub-reflection surface, D(x D ,y D ,z D ) is the vertex of the parabola equation, and x D =x F ,y D =y F ; The xoy plane of the spatial rectangular coordinate system is a plane perpendicular to the incident light, and the incident direction of the light is the negative direction of the z axis; The surface shape function of the central sub-reflecting surface is determined by substituting the coordinate system zero point O(0, 0, 0) and the target focus coordinates corresponding to the central sub-reflecting surface into the initial surface shape equation of the sub-reflecting surface, including: The coordinate system zero point O(0, 0, 0) and the target focus coordinate F(x F ,y F ,z F ) into the parabolic surface equation, we get z D , and then the surface function of the central sub-reflection surface is obtained:

4. The method for designing a reflective beam shaping mirror according to any one of claims 1 to 3, wherein: The method also includes determining the boundary shapes of two adjacent sub-reflection surfaces, specifically including: By making the surface functions of two adjacent sub-reflecting surfaces equal, an accurate analytical solution of the boundaries of the two adjacent sub-reflecting surfaces is obtained, and the accurate analytical solution constitutes the boundary shape of the two adjacent sub-reflecting surfaces.

5. The method for designing a reflective beam shaping mirror according to claim 1, wherein: The reflective surface of the reflective beam shaping mirror is pre-divided into a plurality of sub-reflective surfaces according to the number, position, and energy distribution of the target focal points in the target focal point array A; wherein the energy distribution is used to determine the area of ​​each sub-reflective surface, and the ratio of the area of ​​each sub-reflective surface in the reflective surface array B is proportional to the ratio of the energy value of each corresponding focal point in the target focal point array A. The number and position are used to determine the pre-division method, and the pre-division method includes: When the target focus array A is distributed in M*N horizontal and vertical directions, the reflecting surface is divided horizontally and vertically; wherein M>1, N>1; When the target focus array A is distributed in a 1*N horizontal pattern or in an M*1 vertical pattern, the reflection surface is correspondingly divided into horizontal or vertical rows; When the target focus array A is axially distributed along the light propagation direction, the reflecting surface is divided into annular parts.

6. The method for designing a reflective beam shaping mirror according to claim 5, wherein: When the energy distribution of each target focus in the target focus array A is the same, the areas of each sub-reflection surface divided horizontally and vertically and divided in an annular manner are the same, and the distances of each sub-reflection surface divided in horizontal or vertical columns along the dividing direction are equal.

7. A reflective beam shaping lens that is insensitive to light sources and generates multiple focal points, characterized in that: The reflective surface is designed by the design method of a reflective beam shaping mirror for generating multiple focal points according to any one of claims 1 to 6.

8. The reflective beam shaping mirror according to claim 7, wherein: It also includes a cylindrical base, and the reflecting surface is arranged on the cylindrical base.

9. A reflective beam shaping system that generates multiple focal points and is insensitive to light sources, characterized in that: include: Light source and reflective beam shaping mirror; The reflective surface of the reflective beam shaping mirror is designed using the design method for a reflective beam shaping mirror for generating multiple focal points as described in any one of claims 1 to 6, or the reflective beam shaping mirror is the reflective beam shaping mirror as described in claim 7 or 8.

10. The reflective beam shaping system according to claim 9, wherein: The light source is a collimated incident light source, or an ideal point light source; When the light source is a collimated incident light source, the light source includes a laser and a parabolic collimator for collimating the light emitted by the laser.

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