Programmable 3d beam shaping device based on beamlet printing technology

Abstract

A programmable 3D beam shaping device based on beamlet printing technology, comprising a laser source, the laser source emits initial laser, the initial laser adjusts the polarization state through a rotatable half-wave plate, and then is separated into orthogonal s component beam and p component beam through a first polarization beam splitter prism; the p component beam is expanded and then enters a Dammann grating to generate a diffraction beam containing several diffraction orders; the diffraction beam passes through a second polarization beam splitter prism, a quarter-wave plate and a first focusing element in turn, introduces focal shift by a multi-stage phase plate array, adjusts the angle and position offset of the sub-group of the sub-beam array beam by a spatial light modulator to generate a working beam, the working beam returns to the second polarization beam splitter prism from the original light path and is emitted into a working area by a second focusing element, generating a three-dimensional light field; the device can accurately control the three-dimensional irradiance distribution in the processing area, thereby realizing multi-level and depth-adjustable energy deposition, and significantly improving the quality, efficiency and consistency of processing.

Description

Technical Field

[0001] This invention belongs to the field of optical devices, and specifically relates to a programmable 3D beam shaping device based on sub-beam printing technology. Background Technology

[0002] Early beam shaping methods primarily relied on refractive or reflective optical elements, diffractive optical elements, and field mapping optical elements (such as optical integrators) to obtain beam patterns with fixed geometry and intensity distribution. Related technologies have been disclosed in numerous inventions, such as US6075650A, US11150483B2, US5864430, US5925271A, US9285593B1, US4744615A, and US5676866.

[0003] With the increasing demands of applications such as materials processing and laser surgery, dynamic beam shaping technology, capable of generating variable beam patterns, is gaining increasing attention. For example, US20150009583A1 discloses a method for partially achieving dynamic beam control through the lateral relative movement of a combination of optical elements. In most dynamic beam shaping systems, the spatial light modulator (SLM) plays a central role, modulating the amplitude, phase, polarization, and optical path of the incident beam. Existing dynamic beam shaping methods can be broadly classified into two categories: time-pulse shaping and spatial geometry shaping. Taking spatial geometry shaping as an example, US10884250B2 discloses a method for controlling the beam shape in the Fourier plane based on a digital micromirror device (DMD) and a binary hologram, while US6126288A utilizes a DMD to directly modulate the beam on the projection plane. US5128212 uses a liquid crystal spatial light modulator (LC-SLM) for beam control, while US8111338B2 and WO2018053640A1 achieve dynamic shaping by changing the refractive index of the liquid crystal layer for phase modulation. Another representative approach is dynamic modulation based on micromirrors or acousto-optic devices. For example, US6605796B2 outlines a device for two-dimensional beam shaping using a dynamic micromirror array, US7576907B1 uses an optical dispersive element combined with a one-dimensional LC-SLM for phase and amplitude pulse shaping, and US5526171A discloses a scheme for time shaping based on a dynamic grating of an acousto-optic spatial light modulator.

[0004] With the increasing complexity of modern applications, three-dimensional (3D) beam shaping has become an important technology for improving optical processing and handling performance. For example, in laser material processing, precise sensing and control of the irradiance distribution within the molten pool is required. This necessitates not only controlling the beam shape within the working plane but also adjusting the focal depth along the beam propagation direction. Some existing solutions have attempted to achieve 3D beam control. For instance, US11855348B2 creates a 3D electromagnetic beam configuration using cascaded scattering metasurfaces, US11780029B2 uses mechanically adjustable phase elements along the propagation direction to achieve focus control, and KR101991475B1 utilizes a variable phase plate located within the focused beam to achieve focus control. However, these methods are largely limited to two-dimensional beam shaping or single focal length control, with limited ability to generate 3D dynamic beams. They also suffer from energy loss, additional scattering, and low laser damage resistance thresholds, thus limiting their applicability in demanding applications. Summary of the Invention

[0005] To address the aforementioned problems, this invention proposes a programmable 3D beam shaping device based on sub-beam printing technology. The concept involves using a Dammann grating to split the beam into a highly uniform diffraction array, with each diffraction component retaining the intensity distribution of the original incident wave. A focusing element processes these diffraction components into a far-field N×N sub-beam array, which is then projected onto a multi-stage phase plate array and a reflective spatial light modulator. The sub-beams, after being focused by the multi-stage phase plate array, are programmably adjusted in spatial angle, allowing the sub-beam array to be rearranged, moved, and projected onto multiple different target planes. Ultimately, this efficiently generates a complex dynamic three-dimensional irradiation field within a specified working area, meeting various optical processing and precision control requirements.

[0006] The programmable 3D beam shaping device based on sub-beam printing technology includes a laser source 1, which emits an initial laser. The polarization state of the initial laser is adjusted by a rotatable half-wave plate 2, and then separated into orthogonal s-component beams and p-component beams by a first polarization beam splitter 3. The s-component beams are injected into a beam trash can 4.

[0007] The p-component beam enters the beam expander 5, and after beam expansion, it enters the Damman grating 6 and generates a diffracted beam containing several diffraction orders. The diffracted beam passes through the second polarizing beam splitter 7 and the quarter-wave plate 8 in sequence and then enters the first focusing element 9. After being focused by the first focusing element 9, the diffracted beam enters the multi-stage phase plate array 10.

[0008] The multi-stage phase plate array 10 introduces a focal shift into the diffracted beam, dividing the diffracted beam into several subgroups according to the focal shift level, generating a sub-beam array beam. The sub-beam array beam enters the spatial light modulator 11, which adjusts the angle and position offset of each subgroup of the sub-beam array beam to generate a working beam and reflects the working beam in the opposite direction of the sub-beam array beam. After passing through the first focusing element 9 and the quarter-wave plate 8, the working beam is reflected by the second polarizing beam splitter 7 to the second focusing element 12. The second focusing element 12 projects the subgroups of the working beam onto different target planes in the working area 13, generating a target three-dimensional light field.

[0009] More specifically, the formula for calculating the focal shift introduced by the multi-stage phase plate array 10 for the diffracted beam is as follows:

[0010]

[0011] in:

[0012] In the formula, T represents the thickness of the phase plate, D is the diameter of the spot of the p component beam incident on the Mann grating 6, and n is the refractive index of the multi-stage phase plate array 10. Since the converging beam will generate a focal shift each time it passes through the multi-stage phase plate array 10 and returns after being reflected by the SLM, the effective focal shift is twice the value calculated by the above formula.

[0013] Preferably, the Dammann grating 6 generates M×N diffraction orders, the positions of which are defined by a comb function, denoted as...

[0014]

[0015] Where, a = f / d x and b= f / d y , representing the distance between two adjacent delta functions in the x and y directions, respectively; d is the wavelength of light, f represents the focal length of the first focusing element 9, and d is the focal length of the light. x and d y These are the grating constants on the x-axis and y-axis, respectively; the M×N diffraction orders are represented as the convolution of a single Gaussian function with the corresponding comb function; by grouping the sub-beams of the diffraction beam and recombining them within each sub-group, each sub-beam except the central sub-beam is arranged and reconstructed with the central sub-beam of the group as a reference after undergoing a specific lateral shift.

[0016] Preferably, the intensity of the shaping beam formed on one working surface of the working area 13 is expressed as:

[0017]

[0018] Where I0 represents the peak intensity at the center of the shaping beam, k represents the k-th phase order of the phase plate, k=1,2…K, w k It is the bundle width of the sub-bundle associated with the k-th subgroup, Δx n,k and Δy n,k These represent the offsets of the nth Gaussian sub-bundle within the k-th subgroup along the x-axis and y-axis, respectively. r and r are the angular axis and radial axis of the polar coordinate system, respectively; the overall intensity field on each working surface is the incoherent sum of the focusing sub-beams belonging to the same subgroup and the defocusing sub-beams from other subgroups.

[0019] Preferably, the three-dimensional light intensity distribution printed in working area 13 is represented as follows:

[0020] ,

[0021] ,

[0022] ;

[0023] in λ represents the defocusing amount of the sub-beam within the k-th subgroup at coordinate z, where λ is the wavelength of light, and z R The Rayleigh range is indicated by w0, which is the waist at the sub-beam focal point.

[0024] Preferably, when the focal lengths of the first focusing element 9 and the second focusing element 12 are similar,

[0025]

[0026] This represents the focal shift produced by the k-th subgroup phase plate.

[0027] Preferably, the half-wave plate 2 is mounted on top of a rotatable electric rotary table.

[0028] Preferably, the diffraction beam generated by the Damman grating 6 contains a 6×6 diffraction order.

[0029] Optionally, the second focusing element 12 consists of a diffraction element and a refractive element.

[0030] Preferably, the spatial light modulator 11 is connected to an external host computer, and the data instructions calculated by the external host computer are used to control the angle and position offset of each subgroup of the sub-beam array beam.

[0031] The working principle of this invention is as follows: First, the polarization state of the initial laser is adjusted by the half-wave plate 2, and the p-component beam is separated by the first polarization beam splitter 3 to adjust the intensity of the p-component beam subsequently incident on the Damman grating 6; the beam expander expands the small p-component beam to uniformly illuminate the Damman grating, and the Damman grating divides the beam into several different diffraction orders by introducing phase delay to the p-component beam at different positions on the plane; the second polarization beam splitter 7 allows the p-component diffracted beam from the Damman grating to pass directly through and continue to propagate forward; the quarter-wave plate 8 converts the transmitted linearly polarized p-light into circularly polarized light, and the first focusing element 9 converges the parallel sub-beam array so that it passes through a multi-level phase plate array before reaching the surface of the spatial light modulator; the multi-level phase plate array 10 contains phase structures of different levels, and each diffracted beam is introduced with different axial focal shifts when passing through different levels of regions. In this way, all sub-beams are divided into several subgroups with different preset focal planes, laying the foundation for the subsequent generation of a 3D light field. The spatial light modulator 11 is programmable and can independently and precisely adjust the wavefront of each sub-beam incident on it, and control the exit angle of each sub-beam. It receives computer instructions, "programs" the sub-beam array into working beams, and then reflects them back along the original path. When the working beam returns to the quarter-wave plate 8, it is converted from circularly polarized light back to linearly polarized light. However, due to passing through the quarter-wave plate twice, the polarization direction is rotated by 90 degrees, becoming S-component polarized light. The S-component polarized light is then directly reflected by the second polarizing beam splitter 7 to the direction of the second focusing element. The second focusing element 12 finally converges each sub-beam with its programmed exit angle adjusted onto different planes in the working area. The two-dimensional light fields on each plane overlap to form a three-dimensional light field, thus realizing the generation of a three-dimensional light field.

[0032] The most significant innovation of this invention lies in the introduction of sub-beam digital printing technology. After the beam is graded by a Damman grating, a multi-level phase plate array is used to introduce focal shift, generating several sub-beam groups. By dynamically adjusting the angle and position offset of the sub-beams within each sub-group, programmable beam shaping and control on several different target planes can be achieved.

[0033] The beneficial effects of this invention include:

[0034] 1. In the field of laser processing, it can precisely control the three-dimensional irradiance distribution within the processing area, thereby achieving multi-layered and depth-adjustable energy deposition, significantly improving the quality, efficiency, and consistency of processing.

[0035] 2. In the fields of microscopic imaging and biomedicine, the parallel generation of multi-focal plane light fields can simultaneously acquire imaging information at different depths, improving resolution and tomographic imaging capabilities, and is suitable for high-throughput and dynamic observation of live samples.

[0036] 3. In the field of optical information processing and communication, it can realize the dynamic encoding, decoding and multiplexing of high-dimensional spatial optical modes, significantly improve information capacity and system anti-interference ability, and provide support for cutting-edge directions such as quantum information and free space communication.

[0037] 4. The system structure has good scalability and compatibility, and can be flexibly combined with spatial light modulators, micromirror arrays and refractive / diffractive hybrid optical devices, thus having broad application prospects and practical value. Attached Figure Description

[0038] Figure 1 This is a structural diagram of the programmable 3D beam shaping device based on sub-beam printing technology of the present invention.

[0039] Figure 2 This is a schematic diagram of the process by which the initial laser beam is converted into a diffracted beam according to the present invention.

[0040] Figure 3 This is a schematic diagram of the grouping of diffracted beams by the multi-stage phase plate array of the present invention.

[0041] Figure 4 This is a comparison diagram of the effects of the multi-level phase plate array of the present invention.

[0042] Figure 5a This is a two-dimensional representation of the light field of the programmable 3D beam shaping device based on sub-beam printing technology of the present invention, which is a computer simulation.

[0043] Figure 5b This invention provides a computer-simulated three-dimensional representation of the light field of a programmable 3D beam shaping device based on sub-beam printing technology.

[0044] Figure 6 This is a schematic diagram of the three-dimensional beam printing result of the present invention.

[0045] Figure 7 yes Figure 1 The optimization of the middle element 12 can generate more layers of longitudinal target light field. Detailed Implementation

[0046] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0047] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0048] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0049] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0051] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0052] The present invention will now be described in detail with reference to the accompanying drawings and exemplary embodiments.

[0053] according to Figure 1 The programmable 3D beam shaping device based on sub-beam printing technology includes a laser source 1, which emits an initial laser. The polarization state of the initial laser is adjusted by a rotatable half-wave plate 2, and then separated into orthogonal s-component beams and p-component beams by a first polarization beam splitter 3. The s-component beams are injected into a beam trash can 4.

[0054] according to Figure 2 The p-component beam enters the beam expander 5, and after beam expansion, it enters the Damman grating 6 and generates a diffracted beam containing several diffraction orders. The diffracted beam passes through the second polarizing beam splitter 7 and the quarter-wave plate 8 in sequence and then enters the first focusing element 9. After being focused by the first focusing element 9, the diffracted beam enters the multi-stage phase plate array 10.

[0055] according to Figure 3 and Figure 4 A multi-stage phase plate array 10 introduces a focal shift into the diffracted beam, dividing it into several subgroups according to the focal shift level to generate a sub-beam array beam. The sub-beam array beam enters a spatial light modulator 11, which adjusts the angle and position offset of each subgroup to generate a working beam and reflects it in the opposite direction to the sub-beam array beam. After passing through the first focusing element 9 and the quarter-wave plate 8, the working beam is reflected by the second polarizing beam splitter 7 to the second focusing element 12. The second focusing element 12 projects the subgroups of the working beam onto different target planes in the working area 13, generating a target three-dimensional light field. The three-dimensional light field is as follows: Figure 7 As shown, it includes a first working surface 13a, a second working surface 13b, a third working surface 13c, a fourth working surface 13d, and a fifth working surface 13e. Figure 6 The effect of three-dimensional beam shape achieved by superimposing the light fields on several working surfaces in several working areas 13 into a three-dimensional light field is shown.

[0056] The formula for calculating the focal shift introduced by a multi-stage phase plate array of 10 pairs of diffracted beams is as follows:

[0057]

[0058] in:

[0059] In the formula, T represents the thickness of the phase plate, D is the diameter of the spot of the beam incident on the Mann grating 6, and n is the refractive index of the multi-stage phase plate array 10. Since the converging beam will generate a focal shift each time it passes through the multi-stage phase plate array 10 and is reflected back by the spatial light modulator 11, the effective focal shift is twice the value calculated by the above formula.

[0060] In some embodiments, the half-wave plate 2 is mounted on top of a rotatable electric rotary table.

[0061] In some embodiments, such as Figure 2 As shown, the diffraction beam generated by the Damman grating 6 contains 6×6 diffraction orders.

[0062] In some embodiments, such as Figure 7 As shown, the second focusing element 12 is composed of a diffraction element 121 and a refractive element 122.

[0063] In some embodiments, the spatial light modulator 11 is connected to an external host computer.

[0064] The intensity of a Gaussian beam can be expressed as:

[0065]

[0066] Where w represents the beam width and I0 represents the peak intensity at the center.

[0067] The positions of the M×N diffraction orders produced by the Damman grating 6 can be defined using a comb function, expressed as follows:

[0068]

[0069] Where, a = f / d x and b= f / d y , represent the distance between two adjacent delta functions in the x and y directions, respectively. Here, d is the wavelength of light, f represents the focal length of the first focusing element 9, and d is the focal length of the light. x and d yThese are the grating constants on the x-axis and y-axis, respectively. The M×N diffraction orders can be represented as the convolution of a single Gaussian function with the corresponding comb function. By grouping the sub-beams of the diffraction beam and recombining them within each sub-group, each sub-beam (except the central sub-beam) is arranged and reconstructed with reference to the central sub-beam of the group after a specific lateral shift (wherein, the central sub-beam can be located at the geometric center of the sub-group or set at other positions as needed). After the above processing, the shaped beam formed on a working surface of the working area 13 can be represented as:

[0070]

[0071] Where k represents the k-th (k=1,2…K) phase level of the phase plate, w k It is the bundle width of the sub-bundle associated with the k-th subgroup, Δx n,k and Δy n,k These represent the offsets of the nth Gaussian sub-bundle within the k-th subgroup along the x-axis and y-axis, respectively. And r are the angular and radial axes of the polar coordinate system, respectively. The overall intensity field on each working surface is the incoherent sum of the focusing sub-beams belonging to the same subgroup and the defocusing sub-beams from other subgroups. Finally, the printed three-dimensional light intensity distribution can be represented as:

[0072] ,

[0073] ,

[0074] and (When the focal lengths of the first focusing element 9 and the second focusing element 12 are similar).

[0075] in, λ represents the defocusing amount of the sub-beam within the k-th subgroup at coordinate z, where λ is the wavelength of light, and z R Indicates the Rayleigh range, w0 is the waist at the sub-beam focus. This represents the focal shift produced by the phase plate of the k subgroup.

[0076] Figure 5a and Figure 5b The computer simulation results show the generation of a "flat-top" beam from a single Gaussian beam. First, the incident beam is split into N sub-beams after dynamic power control, and then each sub-beam is spatially redirected and moved to print the target light field distribution. Figure 5a It is a two-dimensional representation of the target light field (where the number of sub-beams N is 4, 6, and 10 respectively); Figure 5bThis is a three-dimensional representation of the target light field (N = 10), with the vertical axis representing relative light intensity and the horizontal axis being x100 micrometers. In these simulations, the shift increment between adjacent sub-beams is set to twice the beam width, and the integral sum includes only the focused sub-beams of a specific subgroup. Parameters include: light wavelength 1.064 micrometers, diameter of the incident beam after beam expander 40 millimeters, grating constant 40 micrometers, focal length of the focusing element 100 millimeters, and a 4-order phase plate with a 1-millimeter difference between each order.

[0077] First, the polarization state of the initial laser is adjusted by the half-wave plate 2, and the p-component beam is separated by the first polarization beam splitter 3 to adjust the intensity of the p-component beam subsequently incident on the Damman grating 6. The beam expander expands the small p-component beam and uniformly illuminates the Damman grating. The Damman grating divides the beam into several different diffraction orders by introducing phase delay to the p-component beam at different positions on the plane. The second polarization beam splitter 7 allows the p-component diffracted beam from the Damman grating to pass directly through and continue to propagate forward. The quarter-wave plate 8 converts the transmitted linearly polarized p-light into circularly polarized light. The first focusing element 9 converges the parallel sub-beam arrays so that they pass through a multi-level phase plate array before reaching the surface of the spatial light modulator. The multi-level phase plate array 10 contains different levels of annular phase structures. Each diffracted beam is introduced with different axial focal shifts when passing through different levels of regions. In this way, all sub-beams are divided into several subgroups with different preset focal planes, laying the foundation for the subsequent generation of a 3D light field. The spatial light modulator 11 is programmable and can independently and precisely adjust the wavefront of each sub-beam incident on it, and control the exit angle of each sub-beam. It receives computer instructions, "programs" the sub-beam array into working beams, and then reflects them back along the original path. When the working beam returns to the quarter-wave plate 8, it is converted from circularly polarized light back to linearly polarized light. However, due to passing through the quarter-wave plate twice, the polarization direction is rotated by 90 degrees, becoming S-component polarized light. The S-component polarized light is then directly reflected by the second polarizing beam splitter 7 to the direction of the second focusing element. The second focusing element 12 finally converges each sub-beam with its programmed exit angle adjusted onto different planes in the working area. The two-dimensional light fields on each plane overlap to form a three-dimensional light field, thus realizing the generation of a three-dimensional light field.

Claims

1. A programmable 3D beam shaping device based on sub-beam printing technology, characterized in that: Includes a laser source (1), which emits an initial laser beam. The initial laser beam is polarized by a rotatable half-wave plate (2) mounted on an electric rotating stage, and then separated into an orthogonal s-component beam and a p-component beam by a first polarizing beam splitter (3). The s-component beam enters the beam trash can (4). The p-component beam enters the beam expander (5), and after beam expansion, it enters the Damman grating (6) and generates a diffracted beam containing several diffraction orders. The diffracted beam passes through the second polarizing beam splitter (7) and the quarter-wave plate (8) in sequence and then enters the first focusing element (9). After being focused by the first focusing element (9), the diffracted beam enters the multi-stage phase plate array (10). The multi-stage phase plate array (10) introduces a focal shift into the diffracted beam. According to the focal shift level, the diffracted beam array is divided into several subgroups, generating several sub-beam array subgroups. The beams of each sub-beam array subgroup are injected into the spatial light modulator (11). The spatial light modulator (11) adjusts the angle and position offset of each subgroup of the sub-beam array beam to generate a working beam and reflects the working beam in the opposite direction of the sub-beam array beam. After the working beam passes through the first focusing element (9) and the quarter-wave plate (8), it is reflected by the second polarizing beam splitter (7) to the second focusing element (12). The second focusing element (12) projects the subgroups of the working beam onto different target planes in the working area (13) to generate a target three-dimensional light field.

2. The programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The formula for calculating the focal shift introduced by the multi-stage phase plate array (10) on the diffracted beam is as follows: in: In the formula, T represents the thickness of the phase plate, D is the diameter of the spot on the Mann grating (6) where the beam is incident, and n is the refractive index of the multi-stage phase plate array (10). Since the converging beam will generate a focal shift each time it passes through the multi-stage phase plate array (10) and is reflected back by the spatial light modulator (11), the effective focal shift is twice the value calculated by the above formula. f θ1 and θ2 are the focal length of the first focusing element, and the incident angle and refraction angle of the beam incident on the first surface of the phase plate, respectively.

3. The programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The Damman grating (6) generates M×N diffraction orders, the positions of which are defined by a comb function, denoted as: in, a = f / d x and b= f / d y , representing the distance between two adjacent delta functions in the x and y directions, respectively; It is the wavelength of light. f This indicates the focal length of the first focusing element (9). d x and d y These are the grating constants on the x-axis and y-axis, respectively; the M×N diffraction orders are represented as the convolution of a single Gaussian function with the corresponding comb function; by grouping the sub-beams of the diffracted beam and recombining them within each sub-group, each sub-beam except the central sub-beam is arranged and reconstructed with the central sub-beam of the group as a reference after undergoing a specific lateral shift.

4. The programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The intensity of the shaping beam formed on one working surface of the working area (13) is expressed as: Where I0 represents the peak intensity at the center of the shaped beam. k This represents the k-th phase level of the phase plate, where k = 1, 2, ..., K. It is the number of sub-bundles within the k-th subgroup. w k It is the bundle width of the sub-bundle associated with the k-th subgroup. Δx n,k and Δy n,k They represent k The first in the subgroup n The offset of a Gaussian sub-beam along the x-axis and y-axis; and r These are the angular and radial axes of the polar coordinate system, respectively; the overall intensity field on each working surface is the incoherent sum of the focusing sub-beams belonging to the same subgroup and the defocusing sub-beams from other subgroups.

5. A programmable 3D beam shaping device based on sub-beam printing technology according to claim 4, characterized in that: The three-dimensional light intensity distribution printed in the working area (13) is represented as follows: , , ； Where z represents the axial distance between the target three-dimensional light field in the working area and the second focusing element. Δx n,k and Δy n,k They represent k The first in the subgroup n The offset of a Gaussian sub-beam along the x-axis and y-axis, λ represents the defocusing amount of the sub-beam within the k-th subgroup at coordinate z, where λ is the wavelength of light. z R Indicates Rayleigh range, w 0 It is the waist at the focal point of the sub-beam.

6. A programmable 3D beam shaping device based on sub-beam printing technology according to claim 5, characterized in that: When the focal lengths of the first focusing element (9) and the second focusing element (12) are similar, This represents the focal shift produced by the k-th subgroup phase plate.

7. A programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The half-wave plate (2) is mounted on the top of a rotatable electric rotary table.

8. A programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The diffraction beam generated by the Damman grating (6) contains 6×6 diffraction orders.

9. A programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The second focusing element (12) consists of a diffraction element and a refraction element.

10. A programmable 3D beam shaping device based on sub-beam printing technology according to claim 1, characterized in that: The spatial light modulator (11) is connected to an external host computer, and the data instructions calculated by the external host computer are used to control the angle and position offset of each subgroup of the sub-beam array beam.

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