CN219202066U - Large scattering angle laser shaping element - Google Patents

Abstract

The embodiment of the application provides a large scattering angle laser shaping element, and a plurality of subunits which are mutually adjacent; the orthographic projection shape of the incident surface of each subunit is set to be polygonal; each side of the polygon shares a side length with an adjacent subunit; the vertex positions of each polygon are formed by random offset, so that the polygons orthographically projected on the incident surface of each subunit are randomly distributed, and the orthographically projected shapes of the incident surfaces of each subunit are randomly transformed, so that the consistency of the shapes of each subunit can be avoided, the coherence of light spots generated after light passes through the micro lenses is reduced, and the uniformity of the light spots generated by the micro lens array is improved.

Description

Large scattering angle laser shaping element

Technical Field

The application relates to the technical field of laser micro devices, in particular to a laser shaping element with a large scattering angle.

Background

With the rapid development of modern optical technology, miniaturization, intellectualization and integration of laser shaping elements have become the current mainstream development trend. Laser shaping elements, such as microlens arrays, are used as micro-optical elements, which are small in size and light in weight, and are widely used in laser display, beam shaping, illumination, three-dimensional imaging, and the like. In general, the array microlens array can be formed by adopting technologies such as electrochemical etching, ultra-precise cutting, femtosecond laser etching, gray scale laser direct writing and the like based on a refraction/diffraction principle. When illumination or three-dimensional imaging is performed, laser is generally used as a light source, and in practical application, a beam of laser is generally emitted to a spot after passing through a micro-lens array, and the spot is used for projection display or in the illumination field.

In the related art, the micro-lens array is formed by closely paving a plurality of sub-units, when illumination or three-dimensional imaging is performed, laser is generally adopted as a light source, in practical application, a beam of laser is generally emitted to a light spot after passing through all the sub-units forming the micro-lens array, and the light spot is used for projection display or in the illumination field.

However, when the shape and size of each subunit are completely consistent, a great coherence is caused, and a speckle phenomenon is generated in a device using laser as a light source due to high coherence of the laser, so that the light spot is unevenly distributed.

Disclosure of Invention

The embodiment of the application provides a large scattering angle laser shaping element, which can avoid the consistency of the shape of each subunit by randomly transforming the shape of the orthographic projection of the incident surface of each subunit, and reduce the coherence of light spots generated after light passes through a micro lens, thereby improving the uniformity of the light spots generated by a micro lens array.

The embodiment of the application provides a large scattering angle laser shaping element, which comprises:

a plurality of sub-units disposed adjacent to each other;

the orthographic projection shape of the incident surface of each subunit is set to be polygonal;

each side of the polygon shares a side length with an adjacent subunit;

the vertex positions of each polygon are formed by random offset, so that the polygons orthographically projected by the incidence plane of each subunit are randomly distributed.

In one possible implementation, the polygon is provided with n-polygons, wherein:

where n >3 and Z represents a set of integers.

In one possible implementation, the vertex positions of the polygons are set to the base shape before the random offset is performed;

at least four interior angles of the basic shape can constitute 360 ° when spliced.

In one possible implementation, the shapes and dimensions of the basic shapes that make up the same microlens array are the same.

In one possible implementation, the area of the base shape and the area of the polygon corresponding to the base shape are calculated separately according to the energy utilization rate of the microlens.

In one possible implementation, the calculation formula of the area of the base shape, and the area of the polygon corresponding to the base shape is as follows:

wherein P is the energy utilization rate of the micro lens array; s is(s) ₀ An area that is the base shape; s is(s) _ij The area of each polygon corresponding to the basic shape; n (N) _x ×N _y To assume that there is N _x ×N _y A subunit.

In one possible implementation, the ratio between the side length of the polygon and the side length of the corresponding base shape is calculated from the offset of the vertices of the base shape.

In one possible implementation, the basic shape is provided with N sides, each side being parallel and equal to the side length on the other side of the center point of the corresponding basic shape;

taking the radial direction of the basic shape as the x axis and taking the axial direction of the basic shape as the y axis, the vertex position of the basic shape is marked as x _i ，y _i The vertex position of the polygon is

The side lengths of the N sides of the basic shape are respectively l ₁ ，l ₂ …l _N The side lengths of the polygons are l 'respectively' ₁ ，l’ ₂ …l’ _N Setting the random side length ratio as K _N The following steps are:

wherein K is _Nmin ≤K _N ≤K _Nmax ；K _Nmin Is the minimum random side length ratio; k (K) _Nmax Is the maximum random side length ratio.

In one possible implementation, each subunit includes a first lens and a second lens, the incident surface of the first lens and the incident surface of the second lens together forming the incident surface of each subunit, the exit surface of the first lens and the exit surface of the second lens together forming the exit surface of each subunit;

the second lens is arranged around the side wall of the first lens, the part of the incident angle of the light reaching the critical angle is positioned in the second lens, the emergent surface of the first lens is arranged as an outwards bent arc surface, and the emergent surface of the second lens is arranged as an inwards bent arc surface;

when light is incident from the incident surfaces of all the subunits, a part of light forms a solid main light spot on the projection surface through the arc-shaped surface which is bent outwards by the first lens, and the other part of light forms a hollow compensation light spot on the projection surface through the arc-shaped surface which is bent inwards by the second lens, the shape of the inner ring of the compensation light spot and the shape of the main light spot are mutually matched, wherein the incident angle of one part of light is smaller than the critical angle, and the incident angle of the other part of light is larger than or equal to the critical angle.

According to the large scattering angle laser shaping element, the micro lens array comprises the plurality of sub-units which are mutually adjacent, the orthographic projection of the incidence surface of each sub-unit is of the polygon shape, each side of the polygon is shared with the adjacent sub-units by the side length, the vertex position of each polygon is formed by random offset, the orthographic projection of the incidence surface of each sub-unit can be randomly transformed, the shape of each sub-unit is prevented from being consistent, the coherence of light spots generated after light passes through the micro lenses is reduced, and the uniformity of the light spots generated by the micro lens array is improved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the application and do not constitute an undue limitation to the application. In the drawings:

FIG. 1 is a schematic cross-sectional view of a subunit according to one embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a basic shape of a sub-unit according to an embodiment of the present application;

FIG. 3 is a schematic view of a basic regular hexagonal shape of a subunit according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of a basic shape of a sub-unit according to an embodiment of the present application;

FIG. 5 is a schematic diagram of a basic shape of a subunit of the present application in an eighteen sided shape;

FIG. 6 is a schematic diagram of a basic dodecagon shape of a subunit according to an embodiment of the present application;

FIG. 7 is a schematic illustration of a polygonal area reduction after a base shape of a subunit provided in an embodiment of the present application is randomized;

FIG. 8 is a schematic diagram of the increase in polygonal area after the base shape of a subunit provided by an embodiment of the present application is randomized;

FIG. 9 is a schematic diagram of a concave structure formed by polygons after the basic shape of a subunit is randomized according to one embodiment of the present application;

FIG. 10 is a schematic diagram of a basic shape random post-polygonal bump formation structure of a subunit provided in an embodiment of the present application;

FIG. 11 is a graph showing the variation of spot parameters with randomness;

FIG. 12 is a schematic view of the shape of the bottom surface of the microlens array prior to random displacement;

FIG. 13 is a simulated view of the incoherent irradiance spot formed in FIG. 12;

FIG. 14 is a simulated view of the coherent irradiance spot formed in FIG. 12;

FIG. 15 is a plot of incoherent/coherent irradiance as a function of spot position;

FIG. 16 is a schematic view of the bottom surface shape of the microlens array of FIG. 12 after random displacement;

FIG. 17 is a spot simulation plot of the coherent irradiance of the microlens array of FIG. 16;

FIG. 18 is a graph showing incoherent irradiance of the microlens array of FIG. 16 as a function of spot location;

FIG. 19 is a graph showing the coherent irradiance of the microlens array of FIG. 16 as a function of spot position.

Reference numerals illustrate:

1-a microlens array; 100-subunits; 101-a first lens; 102-a second lens; 100 a-polygon; 100 b-base shape;

2-facula.

Detailed Description

In order to better understand the technical solutions in the present application, the following description will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, shall fall within the scope of the present application.

It should be noted that in the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, however, the present application may be practiced in other ways than as described herein, and therefore the scope of the present application is not limited by the specific embodiments disclosed below.

In the description of the present application, it should be understood that the terms "center," "upper," "lower," "vertical," "horizontal," "axial," "radial," and the like indicate an orientation or a positional relationship based on that shown in the drawings, and are merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. In this application, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium.

The description herein as relating to "first," "second," etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance thereof or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature.

In the related art, the micro-lens array is formed by closely paving a plurality of sub-units, when illumination or three-dimensional imaging is performed, laser is generally adopted as a light source, in practical application, a beam of laser is generally emitted to a light spot after passing through all the sub-units forming the micro-lens array, and the light spot is used for projection display or in the illumination field.

However, when the shape and size of each subunit are completely consistent, a great coherence is caused, and a speckle phenomenon is generated in a device using laser as a light source due to high coherence of the laser, so that the light spot is unevenly distributed.

Therefore, the application provides a laser shaping element with a large scattering angle, so as to solve the technical problem of uneven light spot distribution generated by a micro lens array in the prior art.

Fig. 1 is a schematic cross-sectional view of a subunit according to an embodiment of the present application, and refer to fig. 1, in which a coordinate system is constructed with a center of a microlens array 1 as a center, a radial direction of the microlens array 1 as an x-axis, and an axial direction of the microlens array 1 as a y-axis.

Fig. 2 is a schematic structural view of a square basic shape of a providing subunit according to an embodiment of the present application, fig. 3 is a schematic structural view of a regular hexagon basic shape of a providing subunit according to an embodiment of the present application, fig. 4 is a schematic structural view of a parallelogram basic shape of a providing subunit according to an embodiment of the present application, fig. 5 is a schematic structural view of an eighteen-sided square basic shape of a providing subunit according to an embodiment of the present application, fig. 6 is a schematic structural view of a twelve-sided square basic shape of a providing subunit according to an embodiment of the present application, and the basic shape of a polygon 100a is shown with reference to fig. 2 to 6.

Fig. 7 is a schematic view of a decrease in area of a polygon after a base shape of a subunit is random, fig. 8 is a schematic view of an increase in area of a polygon after a base shape of a subunit is random, fig. 9 is a schematic view of a recess structure formed by a polygon after a base shape of a subunit is random, fig. 10 is a schematic view of a protrusion structure formed by a polygon after a base shape of a subunit is random, and fig. 7 to 10 are referred to illustrate a base shape 100b and a shape of a polygon 100a after a base shape 100b is random.

The embodiment of the application provides a large scattering angle laser shaping element, which comprises:

a plurality of sub-units 100 disposed adjacent to each other;

the shape of the orthographic projection of the incident surface of each sub-unit 100 is set as a polygon 100a;

each side of the polygon 100a shares a side length with an adjacent subunit 100;

the vertex positions of each polygon 100a are formed with random offsets so that the polygons 100a orthographically projected on the incident surface of each subunit 100 are randomly distributed.

From the above description, it can be seen that the following technical effects are achieved:

according to the large scattering angle laser shaping element, the microlens array 1 comprises the plurality of mutually adjacent subunits 100, the orthographic projection of the incidence surface of each subunit 100 is set to be the polygon 100a, the edge length of each edge of the polygon 100a is shared by the adjacent subunits 100, the vertex position of each polygon 100a is formed by random offset, the orthographic projection of the incidence surface of each subunit 100 can be randomly transformed, the consistency of the shape of each subunit 100 is avoided, the coherence of light spots 2 generated after light passes through the microlenses is reduced, and the uniformity of the light spots 2 generated by the microlens array 1 is improved.

In some examples, polygon 100a is provided with n-polygons, wherein:

where n >3 and Z represents a set of integers. Since, in actual operation, when the polygon 100a is set to a triangle, the spots 2 formed by the microlens array 1 overlap, the number of sides of the polygon 100a is set to be greater than 3. Calculating the above formula may result in n equal to 4, 6, etc., for example, a parallelogram, square, rectangle, regular hexagon can be used as the bottom shape of the subunit 100.

The shape of the light spot 2 of the microlens array 1 is consistent with the boundary shape of the subunit 100, the bottom surface polygon 100a of the subunit 100 is not overlapped and is paved on the whole array plane, and under the condition that the polygon 100a is not centrosymmetric, the translational paving condition is also required to be met, namely, the paving is realized only by a translational mode, so that the shape of the polygon 100a is required to meet the paving.

In the specific implementation, for example, the irregular polygon 100a such as an irregular quadrangle or an irregular pentagon cannot be laid in a single layer only by translation, so that the regular polygon 100a, for example, a square (refer to fig. 2), a regular hexagon (refer to fig. 3), a parallelogram (refer to fig. 4), an octadecano (refer to fig. 5), a dodecagon (refer to fig. 6) or the like can be used as the basic shape 100b, that is, the vertex position of the polygon 100a is set as the basic shape 100b before the random offset is performed;

referring to fig. 2 to 6, when at least four interior angles of the basic shape 100b can constitute 360 ° when spliced, translational tiling of the polygon 100a can be achieved.

Illustratively, the basic shapes 100b constituting the same microlens array 1 are identical in shape and size.

The shapes and the sizes of the basic shapes 100b of the same microlens array 1 are set to be identical, and the vertex positions of the basic shapes 100b can be randomly moved based on the basic shapes 100b, so that the polygons 100a in which the incident surface of each subunit 100 is smiling are randomly distributed.

In some examples, the area of the base shape 100b and the area of the polygon 100a corresponding to the base shape 100b are calculated, respectively, according to the energy utilization rate of the microlens array 1.

In the regularly distributed microlens array 1, the subunits 100 are uniform in shape regardless of the influence of transmittance. The energy utilization rate in the far field can be regarded as 100%, when the shapes of the sub-units 100 are randomly distributed, the energy utilization rate of the array is related to the random front and rear bottom surface area change of each sub-unit 100 from the statistical point of view, and when the bottom surface area change is large, the energy utilization rate is reduced, so that the energy utilization rate can be ensured to ensure the randomness of the shape of the polygon 100a and the energy utilization rate, and the relation between the energy utilization rate and the area of the polygon 100a, the area of the basic shape 100b and the number of the sub-units 100 is calculated.

Illustratively, the area of the base shape 100b, and the area of the polygon 100a corresponding to the base shape 100b are calculated as follows:

wherein P is the energy utilization rate of the microlens array 1; s is(s) ₀ An area of the base shape 100b; s is(s) _ij An area of the polygon 100a corresponding to the basic shape 100b; k (K) _x ×N _y To assume that there is N _x ×N _y A subunit 100.

By calculating the energy utilization rate, the area of the basic shape 100b, the area of the polygon 100a corresponding to the basic shape 100b, and the number of the sub-units 100, the basic shape 100b, the area of the polygon 100a corresponding to the basic shape 100b, and the number of the sub-units 100 can be defined according to the required energy utilization rate in the concrete implementation.

In some examples, a ratio between a side length of the polygon 100a and a side length of the corresponding base shape 100b is calculated from an offset of vertices of the base shape 100 b.

According to the method and the device, the offset ratio of the polygon 100a compared with the basic shape 100b can be obtained by calculating the ratio between the side length of the polygon 100a and the side length of the corresponding basic shape 100b, so that the offset of the vertex is limited in a certain range, and the phenomenon that the energy utilization rate is reduced due to the fact that the vertex offset is large is avoided.

Illustratively, the base shape 100b is provided with N sides, each side being parallel and equal to the side length on the other side of the center point of the corresponding base shape 100b;

taking the radial direction of the basic shape 100b as the x-axis and the axial direction of the basic shape 100b as the y-axis, the vertex position of the basic shape 100b is denoted as x _i ，y _i The vertex position of the polygon 100a is

The N sides of the basic shape 100b have a side length of l ₁ ，l ₂ …l _N The sides of the polygon 100a are l 'respectively' ₁ ，l’ ₂ …l’ _N Setting the random side length ratio as K _N The following steps are:

wherein K is _Nmin ≤K _N ≤K _Nmax ；K _Nmin Is the minimum random side length ratio; k (K) _Nmax Is the maximum random side length ratio.

The present application is made by making K _Nmin ≤K _N ≤K _Nmax Can be used for K _N The deflection of the vertex is limited in a certain range, so that the deflection of the vertex is limited in a certain range, and the reduction of the energy utilization rate caused by larger deflection of the vertex is avoided.

Referring to fig. 7, as the area of the random rear polygon 100a increases, the energy utilization rate decreases; referring to fig. 8, the polygon 100a is reduced in area and the energy utilization rate is unchanged. Wherein, referring to fig. 9, for the concave shape when the area of the polygon 100a is increased, wherein the concave shape is as shown in fig. 9 a, referring to fig. 10, the convex shape when the area of the polygon 100a is reduced, wherein the convex shape is as shown in fig. 10B, since the number of the sub-units 100 of the microlens array 1 is very large, and distributed densely in the space of 100%, the two shapes are offset by the compensation shapes generated by the adjacent lenses, which can be taken into consideration.

Illustratively, when the randomness of the sub-units 100 in the microlens array 1 is too large, the destructive interference effect is enhanced, the uniformity of the light spot 2 is increased, and the energy utilization is reduced. However, when the randomness is increased to a certain extent, the uniformity of the light spot 2 is also affected by the randomness and gradually reduced, fig. 11 is a schematic diagram showing the variation of the light spot parameters along with the randomness, and referring to fig. 11, the uniformity and the energy utilization rate of the light spot 2 under different randomness are shown, wherein a broken line a is a variation graph of the energy utilization rate; the broken line b is a variation graph of the uniformity of the light spot 2, and it can be seen that when the randomness is 15%, the energy utilization rate is 85.48%, and the uniformity of the light spot 2 is 82.31%, so that the balance effect is realized.

The effect on spot 2 uniformity is as follows: the spots 2 generated by each subunit 100 are considered to be uniformly distributed, and only in the case of fig. 7, the uniformity of the spots 2 is unchanged, and in the case of fig. 2 to 10, the uniformity of the spots 2 is reduced, so that with the increasing randomness, the duty cycle of fig. 8 to 10 in the bottom graph is increased, and the uniformity of the spots 2 is reduced.

In some examples, each subunit 100 includes a first lens 101 and a second lens 102, the entrance face of the first lens 101 and the entrance face of the second lens 102 together forming the entrance face of each subunit 100, the exit face of the first lens 101 and the exit face of the second lens 102 together forming the exit face of each subunit 100;

the second lens 102 is arranged around the side wall of the first lens 101, and a part of the incident angle of the light reaching the critical angle is positioned in the second lens 102, the emergent surface of the first lens 101 is arranged as an outwards curved arc surface, and the emergent surface of the second lens 102 is arranged as an inwards curved arc surface;

when light is incident from the incident surface of all the subunits 100, a part of light forms a solid main light spot on the projection surface through the arc-shaped surface of the first lens 101 which is bent outwards, and another part of light forms a hollow compensation light spot on the projection surface through the arc-shaped surface of the second lens 102 which is bent inwards, the shape of the inner ring of the compensation light spot and the shape of the main light spot are mutually adapted, wherein the incident angle of one part of light is smaller than the critical angle, and the incident angle of the other part of light is larger than or equal to the critical angle.

According to the method, the second lens 102 is arranged around the side wall of the first lens 101, the part of the incident angle of the light reaching the critical angle is located in the second lens 102, when the light enters from the incident surface of the subunit 100, before the reflectivity is suddenly changed, a part of the light passes through the outwards bent arc-shaped surface of the first lens 101 and forms a solid main light spot on the projection surface, after the reflectivity is suddenly changed, another part of the light passes through the inwards bent arc-shaped surface of the second lens 102 and forms a hollow compensation light spot on the projection surface, the main light spot is just matched with the hollow compensation light spot to form an actual light spot 2, compared with the prior art, after the incident angle of the light reaches the critical angle, the reflectivity is suddenly changed, scattered light energy is weakened, so that the scattering angle of the micro lens array 1 is limited, in the method, the main light spot is compensated by the compensation light spot, the scattering angle of the micro lens array 1 is not limited by the sudden change of the reflectivity, and the scattering angle of the micro lens array 1 is increased. By the arrangement of the present application, a microlens array 1 capable of increasing the scattering angle of the microlens array 1 is provided.

In some examples, microlens array 1 is formed when a plurality of sub-units 100 are disposed adjacent to each other; when the vertex position of each polygon 100a is formed by random offset, fig. 12 is a schematic diagram of the bottom surface shape before random offset of the microlens array, taking the structure of fig. 12 as an example, fig. 12 is a microlens array 1 formed by splicing 9 subunits 100, wherein the subunits 100 are taken as an example of designing a microlens array 1 with a scattering angle of 41 °, the scattering angle of the first lens 101 is 25 ° and the scattering angle of the second lens 102 is 25 ° -41 °, the sagittal height of the first lens 101 is 5.881 μm, the sagittal height of the second lens 102 is 22.928 μm, the bottom surface radius of the first lens 101 is 15 μm, and the bottom surface radius of the second lens 102 is 12.342 μm, and the basic shape 100b of the subunits 100 can be designed as shown in fig. 12.

FIG. 13 is a simulated view of the incoherent irradiance spot formed in FIG. 12; FIG. 14 is a simulated view of the coherent irradiance spot formed in FIG. 12; comparing fig. 13 and fig. 14, it can be seen that more interference dots appear in the spot simulation diagram of fig. 14.

FIG. 15 is a plot of incoherent/coherent irradiance as a function of spot position; referring to fig. 15, a curve c is a graph of the coherent irradiance of the microlens array of fig. 12 according to the spot position, a curve d is a graph of the coherent irradiance of the microlens array of fig. 12 according to the spot position, and the curve c fluctuates up and down around the curve d, so that it can be seen that the fluctuation range of the curve c is larger.

Fig. 16 is a schematic view of the bottom surface shape of the microlens array of fig. 12 after random displacement. FIG. 17 is a spot simulation plot of the coherent irradiance of the microlens array of FIG. 16; fig. 17 shows a significant decrease in intensity and an increase in uniformity of the interference dots in the spot simulation diagram of fig. 17, as compared to fig. 14.

FIG. 18 is a graph showing incoherent irradiance of the microlens array of FIG. 16 as a function of spot location; curve e is a plot of incoherent irradiance versus spot for the microlens array of fig. 16; FIG. 19 is a graph showing the coherent irradiance of the microlens array of FIG. 18 as a function of spot position. Curve f is a plot of coherent irradiance versus spot for the microlens array of fig. 16; it can be seen that the up-and-down fluctuation range of curve c around curve d is significantly reduced compared with the up-and-down fluctuation range of curve f around curve e, and the coherent irradiance tends to be incoherent irradiance distribution, with improved uniformity.

In fig. 15, 18, and 19, d represents the distance from a certain point on the spot 2 to the center of the spot 2.

It is to be understood that, based on the several embodiments provided in the present application, those skilled in the art may combine, split, reorganize, etc. the embodiments of the present application to obtain other embodiments, where none of the embodiments exceed the protection scope of the present application.

The foregoing detailed description of the embodiments of the present application has further described the objects, technical solutions and advantageous effects thereof, and it should be understood that the foregoing is merely a specific implementation of the embodiments of the present application, and is not intended to limit the scope of the embodiments of the present application, and any modifications, equivalent substitutions, improvements, etc. made on the basis of the technical solutions of the embodiments of the present application should be included in the scope of the embodiments of the present application.

Claims (9)

1. A high dispersion angle laser shaping element, comprising:

a plurality of sub-units (100) disposed adjacent to each other;

the shape of the orthographic projection of the incident surface of each subunit (100) is set as a polygon (100 a);

-each side of the polygon (100 a) shares a side length with the adjacent subunits (100);

the vertex positions of each polygon (100 a) are formed by random offset, so that the polygons (100 a) of the orthographic projection of the incidence plane of each subunit (100) are randomly distributed.

2. The large scattering angle laser shaping element according to claim 1, characterized in that the polygon (100 a) is provided with n-polygons, wherein:

where n >3 and Z represents a set of integers.

3. The large scattering angle laser shaping element according to claim 2, wherein the vertex positions of the polygon (100 a) are set as basic shapes (100 b) before performing random offset;

at least four interior angles of the basic shape (100 b) can constitute 360 ° when spliced.

4. A large scattering angle laser shaping element as claimed in claim 3, characterized in that the basic shapes (100 b) constituting the same microlens array (1) are identical in shape and size.

5. The large scattering angle laser shaping element according to any one of claims 3 or 4, characterized in that an area of the basic shape (100 b) and an area of the polygon (100 a) corresponding to the basic shape (100 b) are calculated, respectively, based on an energy utilization ratio of a microlens.

6. The large scattering angle laser shaping element according to claim 5, wherein the area of the basic shape (100 b) and the area of the polygon (100 a) corresponding to the basic shape (100 b) are calculated as follows:

wherein P is the energy utilization rate of the micro lens array (1); s is(s) ₀ An area for the base shape (100 b); s is(s) _ij -an area of the polygon (100 a) corresponding to the basic shape (100 b); n (N) _x ×N _y To assume that there is N _x ×N _y A subunit (100).

7. The large scattering angle laser shaping element according to any one of claims 3 or 4, characterized in that a ratio between a side length of the polygon (100 a) and a side length of the corresponding basic shape (100 b) is calculated from an offset of vertices of the basic shape (100 b).

8. The large scattering angle laser shaping element as claimed in claim 7, characterized in that said basic shape (100 b) is provided with N sides, each side being parallel and equal to the side length on the other side of the center point of the corresponding basic shape (100 b);

taking the radial direction of the basic shape (100 b) as an x-axis and the axial direction of the basic shape (100 b) as a y-axis, the vertex position of the basic shape (100 b) is denoted as x _i ，y _i The vertex position of the polygon (100 a) is

N sides of the basic shape (100 b)Is respectively l ₁ ，l ₂ …l _N The side lengths of the polygons (100 a) are respectively l' ₁ ，l’ ₂ …l’ _N Setting the random side length ratio as K _N The following steps are:

wherein K is _Nmin ≤K _N ≤K _Nmax ；K _Nmin Is the minimum random side length ratio; k (K) _Nmax Is the maximum random side length ratio.

9. The large scattering angle laser shaping element according to any of claims 1-4, characterized in that each of the sub-units (100) comprises a first lens (101) and a second lens (102), the entrance face of the first lens (101) and the entrance face of the second lens (102) together forming the entrance face of each of the sub-units (100), the exit face of the first lens (101) and the exit face of the second lens (102) together forming the exit face of each of the sub-units (100);

the second lens (102) is arranged around the side wall of the first lens (101), a part of the incident angle of the light reaching a critical angle is positioned in the second lens (102), the emergent surface of the first lens (101) is provided with an outwards bent arc surface, and the emergent surface of the second lens (102) is provided with an inwards bent arc surface;

when light is incident from the incident surface of all the subunits (100), wherein a part of the light forms a solid main light spot on the projection surface through the arc-shaped surface of the first lens (101) which is bent outwards, and the other part of the light forms a hollow compensation light spot on the projection surface through the arc-shaped surface of the second lens (102) which is bent inwards, the shape of the inner ring of the compensation light spot and the shape of the main light spot are mutually matched, wherein the incident angle of the part of the light is smaller than the critical angle, and the incident angle of the other part of the light is larger than or equal to the critical angle.

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