A laser beam shaping device and method

Abstract

The application provides a laser beam shaping device and method, and relates to the technical field of laser beam shaping. By introducing a liquid mirror and utilizing a laser-induced photothermal capillary effect to cause controllable deformation of the liquid surface, dynamic phase modulation and shaping of a laser beam are realized, the problems of high manufacturing cost, inability of dynamic adjustment and sensitivity to wavelength in the prior art are solved, and the effects of low cost, dynamic adjustment and generation of various specific spot appearances are achieved.

Description

Technical Field

[0001] This application relates to the field of laser beam shaping technology, and more specifically, to a laser beam shaping device and method. Background Technology

[0002] The energy of a laser beam output typically exhibits a Gaussian distribution, characterized by high energy at the center and low energy at the edges. This leads to uneven energy distribution, low processing efficiency, and the risk of thermal damage. In applications such as laser precision machining, laser illumination, and optical tweezers, there is a pressing need to reshape the Gaussian beam into specific structures such as a flat-top distribution (uniform energy) or a ring distribution (low energy at the center and high energy at the edges) to improve processing quality and energy utilization. Existing laser beam shaping techniques include aspherical lens shaping, microlens array shaping, liquid crystal spatial light modulators, diffractive optical element shaping, and optical waveguide coupling shaping. These methods generally achieve good shaping results, but each has certain limitations. For example, aspherical lens shaping and microlens array shaping both require customized complex optical structures, resulting in high manufacturing costs and an inability to dynamically adjust the shaping effect. Liquid crystal spatial light modulators (SLMs) and diffractive optical elements (DOEs) rely on phase modulation to achieve beam shaping, which is sensitive to laser wavelength and has high device costs. Optical waveguide coupling shaping methods utilize multiple scattering in the medium to control the uniformity of the output beam spot, but this leads to a deterioration in the divergence angle of the output beam and also cannot dynamically adjust the shaping effect. Therefore, it is necessary to study a laser beam shaping method and device that is low in cost and can dynamically modulate the beam morphology.

[0003] There is currently no effective technical solution to the above problems. Summary of the Invention

[0004] The purpose of this application is to provide a laser beam shaping device and method that can achieve low cost and dynamically modulate the beam morphology to form a variety of specific beam shapes.

[0005] This application provides a laser beam shaping device, including a laser, a beam adjustment device, a beam splitter, a liquid reflector, a lens, and a target area surface;

[0006] The laser is used to emit laser light. The laser beam passes through the beam adjustment device, which is used to adjust the size of the beam. Then, the beam is reflected by the beam splitter onto the liquid mirror, causing the liquid surface of the liquid mirror to deform due to photothermal capillary effect. The beam reflected by the deformed liquid surface passes through the beam splitter and the lens in sequence, and is shaped after being focused by the lens. The shaped beam illuminates the target area surface, and the beam forms a multi-layered ring structure, a ring beam, a circular flat-top beam, and a super-Gaussian beam at different positions on the target area surface.

[0007] Through the above-mentioned solution, the laser beam shaping device provided in this application utilizes the photothermal capillary effect to deform the liquid surface of the liquid reflector, thereby achieving dynamic shaping of the laser beam. It can form multi-layered ring structures, ring beams, circular flat-top beams, and super-Gaussian beams, effectively solving the problems of the inability to dynamically adjust the shaping effect, high cost, and wavelength sensitivity in the prior art.

[0008] Optionally, the system also includes a plane mirror disposed between the lens and the target area surface, wherein the shaped light beam is directed by the plane mirror and then illuminates the target area surface.

[0009] By adding a plane mirror, the direction of the shaped beam can be flexibly adjusted, improving the applicability and layout flexibility of the device.

[0010] Optionally, the liquid in the liquid reflector is a ferrofluid or liquid petroleum hydrocarbon.

[0011] Optionally, the beam adjustment device is a beam expander or a beam reducer.

[0012] Secondly, this application provides a laser beam shaping method, based on any of the laser beam shaping devices described above, the laser beam shaping method comprising:

[0013] Controlling a laser to emit beams of different wavelengths;

[0014] The beam adjustment device is used to adjust the size of the beam.

[0015] The adjusted beam is reflected by a beam splitter onto a liquid mirror;

[0016] The liquid surface of the liquid mirror is deformed by the photothermal capillary effect. The deformed liquid mirror then reflects the light beam to the beam splitter and passes through the beam splitter to illuminate the lens.

[0017] After the light beam is focused by the lens, it is shaped, and the shaped light beam forms corresponding multi-layer ring structure, ring beam, circular flat-top beam and super-Gaussian beam at the first position, second position, third position and fourth position on the target range surface, respectively.

[0018] Through the above scheme, the laser beam shaping method provided in this application, based on the above device, achieves the formation of various specific beam shapes at different positions by controlling the laser to emit beams of different wavelengths and adjusting the beam size, thus providing a dynamically adjustable shaping scheme.

[0019] Optionally, by adjusting the output power of the laser or adjusting the beam size range, the beam can be shaped into corresponding annular beams, circular flat-top beams, and super-Gaussian beams at different locations on the target area.

[0020] Optionally, the deformation of the liquid reflector is a rotating Gaussian deformation, the radius of which is... Determined by the laser beam, the following relationship is satisfied:

[0021] ;

[0022] ;

[0023] In the formula, For the cross-section of the beam The light intensity at the location, The deformation height refers to the height of the maximum concave deformation at the center of the liquid surface deformation of the liquid reflector. For rotational Gaussian deformation, Let the coordinates be two-dimensional coordinates on the cross-section of the beam. For the beam at its maximum intensity The radius at that point.

[0024] Optionally, the modulation phase added to the beam in the liquid reflector is:

[0025] ;

[0026] In the formula, In order to be in The added modulation phase, The imaginary unit, For wave vectors.

[0027] Optionally, after the light beam is focused by the lens, the shaped light beam formed at the first position is a multi-layered annular structure, where the first position is the focal point of the lens. The number of rings in the multi-layered annular structure is related to the deformation height as follows:

[0028] ;

[0029] In the formula, The wavelength of the laser is [wavelength]. The number of rings in the multi-layered annular structure.

[0030] Optionally, the second position, the third position, and the fourth position satisfy the following relationship:

[0031] The range of the second position is: 0 after the focal point of the lens. The third position is: behind the focal point of the lens. The position of the fourth position is defined as follows: behind the focal point of the lens. The position between;

[0032] in, ;

[0033] In the formula, The analog Rayleigh distance of the light beam after the focal point of the lens refers to the scale of the change in the shape of the shaped light spot after passing through the focal point of the lens. It is the radius of the outermost ring structure.

[0034] As can be seen from the above, the laser beam shaping device and method provided in this application introduce a liquid reflector and utilize the laser-induced photothermal capillary effect to cause controllable deformation of the liquid surface, thereby realizing dynamic phase modulation and shaping of the laser beam. This solves the problems of high manufacturing cost, inability to dynamically adjust, and wavelength sensitivity of the shaping device in the prior art, and achieves the effects of low cost, dynamic adjustability, and the ability to generate a variety of specific spot shapes.

[0035] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a laser beam shaping device provided in an embodiment of this application.

[0037] Figure 2 This is a schematic diagram illustrating the effect of a laser beam deforming on a liquid reflector, as provided in an embodiment of this application.

[0038] Figure 3 The morphology of the multi-layered ring structure formed by the laser at a first position on the target area surface, as provided in the embodiments of this application.

[0039] Figure 4 A cross-sectional view of a multi-layered annular structure formed by a laser at a first position on the target area surface, provided in an embodiment of this application.

[0040] Figure 5 The shape of the ring beam formed by the laser at a second position on the target area surface, as provided in the embodiments of this application.

[0041] Figure 6 A cross-sectional view of the annular beam formed by the laser at a second position on the target area surface, provided in an embodiment of this application.

[0042] Figure 7 The morphology of the circular flat-top beam formed by the laser at the third position on the target area surface, as provided in the embodiments of this application.

[0043] Figure 8 A cross-sectional view of a circular flat-topped beam formed by a laser at a third position on the target area surface, as provided in an embodiment of this application.

[0044] Figure 9 The morphology of the super-Gaussian beam formed by the laser at the fourth position on the target area surface, as provided in the embodiments of this application.

[0045] Figure 10 A cross-sectional view of the super-Gaussian beam formed by the laser at the fourth position on the target area surface, as provided in the embodiments of this application.

[0046] Figure 11 The shape of the ring beam output in Embodiment 1 provided in this application.

[0047] Figure 12 A cross-sectional view of the annular beam output in Embodiment 1 provided for the present application.

[0048] Figure 13 The morphology of the circular flat-top beam output in Embodiment 1 provided in this application.

[0049] Figure 14 A cross-sectional view of the circular flat-top beam output in Embodiment 1 provided for the present application.

[0050] Figure 15 The morphology of the super-Gaussian beam output in Embodiment 1 provided for the embodiments of this application.

[0051] Figure 16 A cross-sectional view of the super-Gaussian beam output in Embodiment 1 provided for the present application.

[0052] Figure 17 The morphology of the super-Gaussian beam output in Embodiment 2 provided in this application.

[0053] Figure 18 A cross-sectional view of the super-Gaussian beam output in Embodiment 2 provided for the present application.

[0054] Figure 19 The shape of the first annular beam output in Embodiment 2 provided in this application.

[0055] Figure 20 A cross-sectional view of the first annular beam output in Embodiment 2 provided in this application.

[0056] Figure 21The shape of the second annular beam output in Embodiment 2 provided in this application.

[0057] Figure 22 A cross-sectional view of the second annular beam output in Embodiment 2 provided for the present application.

[0058] Figure 23 The cross-section of the incident light beam intensity and the radius of the light beam in the liquid reflector provided in the embodiments of this application. Location diagram.

[0059] Labeling explanations: 1. Laser; 2. Beam adjustment device; 3. Beam splitter; 4. Liquid mirror; 5. Lens; 6. Plane mirror; 7. Target area surface; 701. First position; 702. Second position; 703. Third position; 704. Fourth position. Detailed Implementation

[0060] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0061] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0062] For example, suppose a precision laser micromachining system needs to cut and surface-treat different materials. For some materials, a uniform laser spot energy distribution is required to avoid localized overheating and improve processing consistency; while for others, a ring-shaped spot is needed for edge treatment or drilling. Existing systems use custom-designed aspherical lens groups for beam shaping. When switching from a flat-top spot to a ring-shaped spot, the operator must stop the production line and manually replace the entire optical module. This is not only time-consuming and causes production interruptions, but also requires recalibrating the optical path each time, increasing operational complexity. Furthermore, if the properties of the processed material change, the spot shape needs to be fine-tuned to optimize the processing effect. Existing immutable optical components cannot achieve this dynamic adjustment, resulting in processing quality that does not meet expectations. Moreover, when the system is upgraded or a different wavelength laser is used, the existing shaping components are wavelength-sensitive, potentially requiring the redesign and manufacture of new optical components, further increasing the cost of system maintenance and upgrades.

[0063] If the aforementioned problems are not addressed, laser processing systems will continue to face challenges such as low production efficiency, inconsistent processing quality, and high operating costs. Specifically, the inability to dynamically adjust beam morphology will limit the system's application range and flexibility, making it difficult to adapt to diverse processing needs. Dependence on specific wavelengths will hinder the system's ability to be compatible with different laser sources, increasing the complexity of upgrades and maintenance. Simultaneously, high manufacturing and replacement costs will directly impact the initial investment and long-term economic benefits of the equipment. Furthermore, the deterioration of the beam divergence angle will lead to a reduction in energy density, affecting processing accuracy and efficiency, and may even cause thermal damage to materials, thus limiting the application potential of laser technology in precision manufacturing, advanced materials processing, and other fields.

[0064] Faced with the aforementioned problems, this application first considered beam shaping by combining existing optical elements, such as aspherical lens groups, microlens arrays, or diffractive optical elements (DOEs). However, while this method can achieve specific shaping effects in certain situations, its complex structure leads to high manufacturing costs, and once manufactured, the shaping effect is fixed and cannot be dynamically adjusted according to actual needs. To address this, existing technologies introduce variable optical elements, such as liquid crystal spatial light modulators (SLMs), to achieve dynamic modulation. However, while these devices offer the possibility of dynamic adjustment, they generally suffer from sensitivity to laser wavelength, and the devices themselves are costly, which conflicts with the goal of this application seeking a low-cost solution. Furthermore, optical waveguide coupling shaping methods have also been considered, which utilize multiple scattering in the medium to control the uniformity of the output beam spot. However, this method typically leads to a worse divergence angle of the output beam and also lacks dynamic adjustment capability.

[0065] After weighing the advantages and disadvantages of the various solutions mentioned above, this application recognizes that a novel method based on variable interfaces is needed to achieve low-cost, dynamically tunable, and wavelength-insensitive beam shaping. Specifically, this application conceives a technical path for beam shaping using the controllable deformation of a liquid interface. By utilizing the photothermal capillary effect of laser-induced liquid surface deformation, precise control of the liquid surface of a liquid reflector can be achieved, causing a preset deformation, thereby modulating the phase of the incident beam. This method avoids the customization of complex solid-state optical components, reduces manufacturing costs, and the controllability of the liquid surface deformation provides dynamic adjustment capabilities. For example, by adjusting the power or beam size of the incident laser, the degree and shape of the liquid surface deformation can be changed, thereby achieving the shaping of different beam spots.

[0066] Please refer to Figures 1-23 This application provides a laser beam shaping device and method that can achieve low cost and dynamically modulate the beam morphology to form a variety of specific beam shapes.

[0067] This application provides a laser beam shaping device, including a laser 1, a beam adjustment device 2, a beam splitter 3, a liquid reflector 4, a lens 5, and a target area surface 7;

[0068] Laser 1 is used to emit laser light. The laser beam passes through beam adjustment device 2, which is used to adjust the size of the beam. Then the beam is reflected by beam splitter 3 onto liquid mirror 4, causing the liquid surface of liquid mirror 4 to deform due to photothermal capillary effect. The beam reflected by the deformed liquid surface passes through beam splitter 3 and lens 5 in sequence, and is shaped after being focused by lens 5. The shaped beam illuminates the target area surface 7. The beam forms a multi-layer ring structure, a ring beam, a circular flat-top beam, and a super-Gaussian beam at different positions on the target area surface 7.

[0069] Among them, beam splitter 3 refers to the device used to separate or combine beams. It can be a prism beam splitter, a beam splitter plate, or a polarizing beam splitter, etc. It is mainly used to guide the path of the laser beam so that it can irradiate the liquid reflector 4 and allow the shaped beam to pass through.

[0070] Among them, the liquid reflector 4 refers to a device that can reflect a light beam through a liquid surface. The liquid surface can deform under specific conditions. It can be a container that holds liquids, such as ferrofluids, water, or other liquids with suitable optical and thermal properties. It is mainly used to modulate the phase of the incident light beam through the deformation of the liquid surface to achieve beam shaping.

[0071] Lens 5 refers to an optical element used to focus the beam. It can be a convex lens or a lens group, etc. It is mainly used to focus the beam modulated by the liquid reflector 4, thereby converting the phase modulation into a change in the intensity distribution of the beam and realizing beam shaping.

[0072] Among them, the target range surface 7 refers to the plane that the beam finally illuminates after shaping. It can be a screen, the surface of a workpiece, or the plane of a detector, etc. It is mainly used to receive the shaped beam and display different shapes of light spots.

[0073] Specifically, such as Figure 1 As shown, the laser beam emitted by laser 1 first passes through beam adjustment device 2, where its size is adjusted to a preset range. Subsequently, the adjusted beam is reflected by beam splitter 3 and guided to the liquid surface of liquid mirror 4. When the laser irradiates liquid mirror 4, the liquid surface absorbs laser energy, generating a local temperature gradient, which in turn induces a change in surface tension, causing photothermal capillary deformation of the liquid surface, such as… Figure 2 As shown. This deformation introduces a specific phase modulation into the reflected beam. The beam carrying phase information passes through beam splitter 3 again and enters lens 5. Lens 5 focuses the beam, converting the phase modulation introduced by the liquid surface deformation into a change in the intensity distribution of the beam in space, thus completing beam shaping. The shaped beam finally illuminates the target area surface 7. Depending on the different positions of the beam on the target area surface 7, it can form a multi-layered ring structure, a ring beam, a circular flat-top beam, and a super-Gaussian beam, as shown. Figures 3-10 As shown. The entire process achieves dynamic control of liquid surface deformation by controlling laser parameters and beam size, thereby realizing dynamic modulation of the beam morphology.

[0074] This scheme utilizes the photothermal capillary effect to achieve liquid surface deformation, replacing traditional, expensive, and fixed optical components, significantly reducing the manufacturing cost of the device. Simultaneously, by adjusting the laser parameters, the liquid surface deformation can be controlled dynamically in real time, thereby achieving flexible modulation of the beam shape and overcoming the limitation of traditional methods that cannot be dynamically adjusted. Furthermore, this scheme has low sensitivity to laser wavelength, broadening its application range. Ultimately, this scheme can generate various specific beam shapes on the target surface according to actual needs, such as multi-layered ring structures, ring beams, circular flat-top beams, and super-Gaussian beams, meeting the requirements of different application scenarios for beam structure.

[0075] In some embodiments, a plane mirror 6 is also included. The plane mirror 6 is disposed between the lens 5 and the target area surface 7. The shaped light beam is irradiated onto the target area surface 7 after its direction is adjusted by the plane mirror 6.

[0076] Among them, the plane mirror 6 refers to an optical element with a flat reflective surface, which can be made of coated glass, metal or high reflectivity ceramic material, and is used to change the propagation direction of the light beam without changing its converging or diverging characteristics.

[0077] Specifically, in the laser beam shaping device, the laser beam emitted by laser 1 is sized by beam adjustment device 2 and then reflected by beam splitter 3 to liquid reflector 4. The liquid surface of liquid reflector 4 deforms under photothermal capillary effect, thereby modulating the incident beam. The beam reflected by the deformed liquid surface passes through beam splitter 3 again and is focused and shaped by lens 5 to form a shaped beam with a specific spot shape. Without plane reflector 6, the shaped beam would directly illuminate the target area surface 7 along a fixed straight path emitted from lens 5. However, to meet the flexible requirements for beam propagation direction in practical applications, such as integrating equipment in a compact space or guiding the beam to a non-direct position, this solution introduces plane reflector 6 between lens 5 and target area surface 7. This plane reflector 6 receives the shaped beam emitted from lens 5, and the propagation direction of the shaped beam can be changed through the reflection of the plane reflector 6. This means that the beam, which was originally in a fixed direction, can now be precisely guided to any desired position on the target surface 7 by adjusting the angle of the plane mirror 6. This design allows the entire laser beam shaping device to maintain its core shaping function while gaining spatial layout flexibility and application adaptability, enabling it to better adapt to various complex industrial or scientific research environments, thereby overcoming the spatial limitations caused by direct beam illumination.

[0078] In some embodiments, the liquid in the liquid reflector 4 is a ferromagnetic fluid or liquid petroleum hydrocarbon.

[0079] Specifically, the liquid in the liquid reflector 4 is either a ferrofluid or liquid petroleum hydrocarbon. A ferrofluid is a special colloidal suspension formed by uniformly dispersing nanoscale magnetic particles in a carrier liquid. This fluid not only possesses the fluidity of a liquid but also exhibits unique magnetic response characteristics and excellent photothermal conversion capabilities due to its internal magnetic nanoparticles. For example, magnetic nanoparticles can effectively absorb light energy and convert it into heat energy, thereby generating a local temperature gradient and influencing the surface tension of the fluid. This characteristic allows the ferrofluid to exhibit deformation behavior different from traditional liquids under photothermal effects, providing a basis for achieving more precise and controllable liquid surface deformation. Alternatively, the liquid in the liquid reflector 4 can also be liquid petroleum hydrocarbon, which is a low-cost alternative.

[0080] In some embodiments, the beam adjustment device 2 is a beam expander or a beam reducer.

[0081] Specifically, this scheme clarifies that the beam adjustment device 2 is either a beam expander or a beam reducer, thereby enabling greater flexibility and controllability in adjusting the laser beam size. When it is necessary to increase the size of the laser beam, the beam expander can effectively achieve this function, for example, to allow the beam to cover a larger area of ​​the liquid mirror 4, or to reduce the power density of the beam on the liquid mirror 4 to avoid overheating. By using the beam expander, the magnification factor of the beam can be adjusted according to actual needs, thereby providing a suitable spot size and energy distribution for the subsequent photothermal capillary effect. When it is necessary to reduce the size of the laser beam, the beam reducer can effectively achieve this function, for example, to increase the power density of the beam on the liquid mirror 4 to enhance the photothermal capillary effect, or to focus the beam onto a smaller area. By using the beam reducer, the reduction factor of the beam can be adjusted according to actual needs, thereby providing a suitable spot size and energy distribution for the subsequent photothermal capillary effect. This precise beam size adjustment capability directly affects the intensity and range of the photothermal capillary effect induced by the laser on the liquid mirror 4, and thus determines the specific shape of the liquid surface deformation. Precise control of liquid surface deformation is crucial for achieving various beam shaping techniques, such as multi-layered annular structures, ring beams, circular flat-top beams, and super-Gaussian beams. Therefore, by providing either a beam expander or a beam shrinker, this approach allows for more flexible and controllable beam size adjustment. It enables the selection of appropriate beam sizes based on different shaping requirements, thus providing more precise input conditions for subsequent liquid surface deformation and beam shaping, and facilitating the generation of various shaping effects.

[0082] Secondly, this application provides a laser beam shaping method, based on any of the laser beam shaping devices mentioned above, the laser beam shaping method comprising:

[0083] Control laser 1 to emit beams of different wavelengths;

[0084] The beam adjustment device 2 adjusts the size of the beam;

[0085] The adjusted beam is reflected by beam splitter 3 onto liquid mirror 4;

[0086] The liquid surface of the liquid mirror 4 is deformed by the photothermal capillary effect. The deformed liquid mirror 4 then reflects the light beam to the beam splitter 3 and passes through the beam splitter 3 to illuminate the lens 5.

[0087] After the beam is focused by lens 5, it is shaped. The shaped beam forms corresponding multi-layered ring structures, ring beams, circular flat-top beams and super-Gaussian beams at the first position 701, the second position 702, the third position 703 and the fourth position 704 on the target range surface 7.

[0088] Specifically, firstly, by controlling the laser 1 to emit beams of different wavelengths, a fundamental control dimension is provided for the entire shaping process. Different wavelengths of laser light produce different energy absorption and thermal effects on the liquid mirror 4, thus affecting the degree and mode of liquid surface deformation. This lays the physical foundation for achieving various beam shaping effects. Based on this, the beam size is adjusted by the beam adjustment device 2, further refining the parameters of the incident beam. Changes in beam size directly affect its energy density distribution on the liquid mirror 4, thereby influencing the range and depth of liquid surface deformation caused by photothermal capillary effect. This dual-parameter (wavelength and size) control capability allows for highly controllable and varied liquid surface deformation, enabling the generation of different types of phase modulation. Subsequently, the adjusted beam is accurately guided onto the liquid surface of the liquid mirror 4 by the beam splitter 3. As the core shaping element, the liquid surface of the liquid mirror 4 deforms under the action of the incident laser using the photothermal capillary effect. This deformation essentially introduces controllable phase modulation into the incident beam. The deformed liquid reflector 4 reflects the phase-modulated laser beam back to the beam splitter 3, allowing it to pass through the beam splitter 3 and finally illuminate the lens 5. The lens 5 plays a crucial role in this process, focusing the beam modulated by the liquid reflector 4. The focusing action of the lens 5 transforms the phase modulation introduced by the liquid surface deformation into the shaping of the spatial intensity distribution. It is through precise control of the laser wavelength, beam size, and the resulting liquid surface deformation that the shaped beam can form specific beam shapes at different preset positions on the target surface 7, such as the first position 701, the second position 702, the third position 703, and the fourth position 704. These beam shapes include multi-layered ring structures, ring beams, circular flat-top beams, and super-Gaussian beams, such as... Figures 3-10 As shown. Overall, this method, through dynamic control of the laser source and beam parameters, combined with the unique shaping capability of the liquid reflector 4 in the device, achieves laser beam shaping with various functions and forms that are difficult to achieve with traditional optical components. This method not only overcomes the limitations of existing technologies in terms of single beam shaping effect and difficulty in dynamic adjustment, but also, through the coordinated control of laser wavelength and beam size, makes the beam shaping process more flexible and precise. Thus, it realizes the dynamic generation and position switching of various specific beam shapes on the target area surface 7, greatly expanding the application potential of lasers in precision machining, optical sensing and other fields.

[0089] In some implementations, by adjusting the output power of the laser 1 or adjusting the beam size range, the beam can be shaped into a corresponding annular beam, a circular flat-top beam, and a super-Gaussian beam at different positions on the target range surface 7.

[0090] The beam size range refers to the size of the cross-section of the laser beam during its propagation.

[0091] Specifically, this scheme introduces the adjustment of the output power or beam size range of laser 1, enabling the laser beam shaping method to achieve precise control over the corresponding positions of different beam shapes on the target area surface 7. Specifically, during the laser beam shaping process, firstly, the beam emitted by laser 1 is sized by beam adjustment device 2 and then reflected onto liquid reflector 4. The liquid surface of liquid reflector 4 deforms under the influence of photothermal capillary effect; this deformation acts as a dynamic phase modulator, affecting the phase distribution of the reflected beam. Subsequently, the deformed beam passes through beam splitter 3 and is focused and shaped by lens 5, ultimately forming a specific beam shape on the target area surface 7. To achieve precise control over these beam shapes and their positions on the target area surface 7, this scheme provides two adjustment methods. On the one hand, by adjusting the output power of laser 1, the laser energy density incident on liquid reflector 4 can be directly affected, thereby finely controlling the degree and shape of liquid surface deformation. Precise control of liquid surface deformation affects the total number of rings in the multi-layered annular structure at the focal point, and alters the analog Rayleigh distance of the beam after passing through the focal point of lens 5. This distance is the scale of the shape change of the shaped beam. Therefore, by adjusting the output power, specific characteristics of the final shaped beam shape, such as the diameter of the rings, the uniformity of the flat top, or the steepness of the super-Gaussian beam, can be precisely controlled. On the other hand, by adjusting the beam size range, for example using a beam expander or beam reducer, the irradiation area and energy density distribution of the laser beam on the liquid reflector 4 can be changed, thereby altering the ring radius of the outermost annular structure of the ring spot at the focal point. By comprehensively adjusting the output power and beam size, the phase modulation effect of the liquid reflector 4 can be controlled more flexibly and precisely, thereby achieving precise shaping of corresponding annular beams, circular flat-top beams, and super-Gaussian beams at different positions on the target area surface 7. This adjustment mechanism, combined with the basic methods of using photothermal capillary effect to deform the liquid surface and focusing and shaping with lens 5, transforms the entire shaping process from a single shape generation to a dynamic and precisely controllable shape and position matching, greatly improving the practicality and adaptability of the shaping method.

[0092] In some embodiments, the liquid reflector 4 undergoes a rotating Gaussian deformation, the radius of which is... Determined by the laser beam, the following relationship is satisfied:

[0093] ;

[0094] ;

[0095] In the formula, For the cross-section of the beam The light intensity at the location, The deformation height refers to the height of the maximum concave deformation at the center of the liquid surface deformation of the liquid reflector 4. For rotational Gaussian deformation (i.e., z-axis (e.g.)) Figure 2 middle The indicated height direction) height). Let the coordinates be two-dimensional coordinates on the cross-section of the beam. For the beam at its maximum intensity radius at (e.g.) Figure 23 In ).

[0096] Specifically, such as Figure 2 As shown, when the incident beam is a Gaussian beam, its energy is concentrated at the center, causing the central region of the liquid reflector 4 to undergo maximum thermal deformation, forming a precise rotating Gaussian-shaped depression. This precise liquid surface deformation allows the phase of the reflected beam to be precisely modulated. The deformed liquid reflector 4 reflects the beam back to the beam splitter 3 and through the beam splitter 3 to illuminate the lens 5. After the lens 5 focuses the beam, due to the previously precise phase modulation, the beam can undergo precise shaping, thus forming corresponding annular beams, circular flat-top beams, and super-Gaussian beams at different positions on the target surface 7. It is precisely because this precise mathematical correspondence is established between the liquid surface deformation and the intensity distribution of the incident beam that the liquid surface deformation caused by the photothermal capillary effect can more accurately respond to the energy distribution of the incident beam. In this way, the required liquid surface deformation parameters can be derived from the desired shaping effect, thereby guiding the adjustment of the output power or beam size of laser 1. This achieves precise control and optimization of the shaping beam, ensuring that a high-quality ring beam, circular flat-top beam, or super-Gaussian beam is stably obtained on the target surface 7.

[0097] In some embodiments, the modulation phase added to the beam in the liquid reflector 4 is:

[0098] ;

[0099] In the formula, In order to be in The added modulation phase, The imaginary unit, For wave vectors.

[0100] In this context, modulation phase refers to the change in the wavefront of a light wave relative to a reference plane or its initial state during propagation in space. Wave vector is a vector that describes the direction and wavelength of wave propagation.

[0101] Specifically, this scheme explicitly defines the modulation phase expression of the beam within the liquid reflector 4, directly linking phase modulation to the height of liquid surface deformation. This scheme clarifies how the deformation of the liquid reflector 4 modulates the phase of the incident beam, thereby enabling more precise prediction and control of the beam's shape. This is of great significance for achieving precise control of the beam spot shape in applications such as laser precision machining and laser illumination, effectively improving processing quality and energy utilization.

[0102] In some embodiments, after the light beam is focused by lens 5, the shaped light beam formed at the first position 701 is a multi-layered annular structure. The first position 701 is the focal point of lens 5, and the number of rings in the multi-layered annular structure has the following relationship with the deformation height:

[0103] ;

[0104] In the formula, The wavelength of the laser. The number of rings in a multi-layered ring structure.

[0105] Among them, the multi-layered ring structure refers to the beam shape, after shaping, exhibiting a spot pattern on its cross-section composed of multiple concentric rings. (Number of rings) It refers to the number of visible and identifiable concentric rings in a multi-layered ring structure.

[0106] Specifically, when the light beam passes through the liquid reflector 4 and obtains a height determined by the deformation... Determined modulation phase Subsequently, the beam carrying specific phase information is focused by lens 5. The focusing effect of lens 5 converts the phase information of the beam into a spatial intensity distribution. This is due to the deformation of the liquid mirror 4 (especially the height of the maximum concave deformation at the center). The phase distribution characteristics of the reflected beam are directly determined by the lens 5, and this phase distribution, after being subjected to Fourier transform by lens 5, can form a specific diffraction pattern. When the deformation is high... With laser wavelength When certain conditions are met, the resulting diffraction pattern exhibits a multi-layered ring structure, such as... Figure 3 and Figure 4 As shown. This scheme establishes the number of rings in a multi-layered ring structure through experiments and theoretical derivation. With deformation height and laser wavelength Precise mathematical relationship between them It is precisely because of the introduction of this quantitative relationship that operators can determine the expected number of rings. Combined with known laser wavelengths The required deformation height of the liquid reflector was calculated in reverse. This ability to deduce control parameters from the results greatly improves the controllability and accuracy of the beam shaping process. Therefore, this scheme establishes a direct link between phase modulation and the quantization parameters of the final shaping effect, forming a complete and predictable closed-loop beam shaping control.

[0107] In some implementations, the second position 702, the third position 703, and the fourth position 704 satisfy the following relationship:

[0108] The range of the second position 702 is: 0 after the focal point of lens 5. The third position 703 is located behind the focal point of lens 5. The position, the range of the fourth position 704, is: behind the focal point of lens 5. The position between;

[0109] in, ;

[0110] In the formula, This is the analog Rayleigh distance of the light beam behind the focal point of lens 5. The analog Rayleigh distance refers to the scale of the change in the shape of the shaped light spot after passing through the focal point of lens 5. It is the radius of the outermost ring structure.

[0111] Specifically, this application introduces an analogy to Rayleigh distance. Based on this distance, the specific formation positions of the ring beam, the circular flat-top beam, and the super-Gaussian beam behind the focal point of lens 5 are defined, thereby achieving precise control over the formation positions of different beam shapes on the target area surface 7. In the laser beam shaping method, the liquid surface of the liquid reflector 4 is first deformed by the photothermal capillary effect. This deformation modulates the phase of the incident beam, thereby causing the beam to form a multi-layered ring structure at the focal point (first position 701) after focusing by lens 5. The ring radius of this multi-layered ring structure, especially the ring radius of the outermost ring structure... With the wavelength of the laser Together they determine the analog Rayleigh distance . This represents a characteristic scale of the morphological changes in the shaped light spot, providing a quantitative benchmark that allows for precise prediction and control of the axial evolution of the light spot morphology. Based on this analogy with Rayleigh distance... This application precisely defines the formation positions of different beam patterns. The annular beam is set at 0 to 0 after the focal point of lens 5. The position between, such as Figure 5 and Figure 6 As shown, this utilizes the characteristic that the light beam has not fully converged or diverged near the focal point, effectively forming a clear ring structure in this region. The circular, flat-topped beam is precisely positioned behind the focal point of lens 5. Location, such as Figure 7 and Figure 8 As shown, at this specific location, the energy distribution of the beam tends to be uniform, which is beneficial for obtaining the ideal flat-top effect. The super-Gaussian beam is then set behind the focal point of lens 5. arrive The position between, such as Figure 9 and Figure 10 As shown, this utilizes the characteristic that a beam gradually diverges and tends towards a Gaussian distribution after passing through the focal point. By controlling this range, a super-Gaussian beam with higher-order Gaussian properties can be obtained. This is based on an analogy to Rayleigh distance. This quantitative positioning method eliminates reliance on empirical adjustments in the beam shaping process, instead basing it on the physical properties of the beam itself and quantitative parameters of the shaping effect. By linking the formation positions of different beam shapes to this scale, the shaping process becomes more predictable and controllable. It allows for precise determination of the target position based on actual beam parameters and the desired shaping effect, thereby optimizing the shaping quality. This method, combined with previous techniques using liquid mirrors to deform and form multi-layered ring structures, creates a complete, quantitatively controllable laser beam shaping system, significantly improving the accuracy and controllability of the shaping effect.

[0112] In Example 1, the wavelength of the laser output by laser 1 is 532nm, and the beam reaches its maximum intensity at... The radius at the point is 0.5mm. Ferrofluid is used as the liquid reflector 4. The focal length of lens 5 is 100mm. The target surface 7 is located 50mm behind the focal point of lens 5. The size of the input beam is adjusted by a beam expander (at maximum light intensity). radius at The range is 0.5mm. 1.5mm, to increase the deformation height Keep it constant at 1μm, when When =0.5mm, The beam is 476.3mm long and outputs a ring beam with high edge intensity and low center intensity at point 7 of the target area. That is, the target surface 7 is located 0 to 0 behind the focal point of lens 5. (the position between), such as Figures 11-12 As shown; when When the radius is 1mm, Z is 150.4mm, and a circular flat-top beam is output at point 7 on the target area surface. That is, the target surface 7 is located behind the focal point of lens 5. (location), such as Figure 13 and Figure 14 As shown; when When the radius is 1.5mm, Z is 52.2mm, and a gently centered super-Gaussian beam is output at point 7 on the target area surface. That is, the target surface 7 is located behind the focal point of lens 5. (positions between Z), such as Figure 15 and Figure 16 As shown.

[0113] In Example 2, the wavelength of the laser output by laser 1 is 632nm, and the beam reaches its maximum intensity at... The radius of the target surface 7 is 1 mm. A ferrofluid is used as the liquid reflector 4, the focal length of the lens 5 is 200 mm, and the beam expander magnification is 1. The target surface 7 is located 400 mm behind the focal point of the lens 5. Without changing the size of the input beam, the deformation height of the liquid reflector 4 is adjusted to 1.5 μm by adjusting the output power of the laser 1. Variations between 5μm, when When the diameter is 1.5 μm, Z is 1192 mm, and a super-Gaussian beam with a flat center is output at point 7 on the target area. That is, the target surface 7 is located behind the focal point of lens 5. (positions between Z), such as Figure 17 and Figure 18 As shown; when When the diameter is 3μm, Z is 4331mm, and a first annular beam with high edge intensity and low center intensity is output at the target area surface 7. That is, the target surface 7 is located 0 to 0 behind the focal point of lens 5. (the position between), such as Figure 19 and Figure 20 As shown; when When the diameter is 5μm, Z is 12741mm, and a second annular beam with a larger size than the first annular beam is output at the target area plane 7. That is, the target surface 7 is located 0 to 0 behind the focal point of lens 5. (the position between), such as Figure 21 and Figure 22 As shown.

[0114] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0115] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A laser beam shaping device, characterized by, The laser (1), the beam adjusting device (2), the beam splitter (3), the liquid mirror (4), the lens (5) and the target range surface (7); The laser (1) is used for emitting laser, the beam of the laser passes through the beam adjusting device (2), the beam adjusting device (2) is used for adjusting the size of the beam, then the beam passes through the beam splitter (3) and is reflected to the liquid mirror (4), the liquid surface of the liquid mirror (4) is deformed by the photothermal capillary effect, the light beam reflected by the deformed liquid surface passes through the beam splitter (3) and the lens (5) in turn, and is focused by the lens (5) to be reshaped, the reshaped light beam is irradiated on the target range surface (7), and the light beam forms a plurality of ring structures, a ring beam, a circular flat-top beam and a super-Gaussian beam at different positions of the target range surface (7).

2. The laser beam shaper device of claim 1, wherein, The planar mirror (6) is arranged between the lens (5) and the target range surface (7), and the reshaped light beam is adjusted in direction by the planar mirror (6) and irradiated on the target range surface (7).

3. The laser beam shaper of claim 1, wherein, The liquid of the liquid mirror (4) is ferrofluid or liquid petroleum hydrocarbon.

4. The laser beam shaper of claim 1, wherein, The beam adjusting device (2) is a beam expander or a beam reducer.

5. A method of laser beam shaping, characterized by, The laser beam shaping device and the laser beam shaping method of any one of claims 1-4, The laser (1) is controlled to emit light beams of different wavelengths; The beam adjusting device (2) is controlled to adjust the size of the light beam; The adjusted light beam is reflected to the liquid mirror (4) by the beam splitter (3); The liquid surface of the liquid mirror (4) is deformed by the photothermal capillary effect, and the deformed liquid mirror (4) reflects the light beam to the beam splitter (3) and passes through the beam splitter (3) to irradiate the lens (5); The lens (5) is used for focusing the light beam to be reshaped, and the reshaped light beam forms a plurality of ring structures, a ring beam, a circular flat-top beam and a super-Gaussian beam at a first position (701), a second position (702), a third position (703) and a fourth position (704) of the target range surface (7) respectively.

6. The method of claim 5, wherein, The output power of the laser (1) is adjusted, or the size range of the light beam is adjusted, so that the light beam is reshaped into a corresponding ring beam, a circular flat-top beam and a super-Gaussian beam at different positions of the target range surface (7).

7. The method of claim 6, wherein, The deformation of the liquid mirror (4) is a rotationally Gaussian deformation, whose radius is determined by the laser beam and satisfies the following relationship: ； ； wherein is the light intensity at the position on the cross section of the light beam, is the height of the deformation, which is the height of the maximum concave deformation at the center of the deformation of the liquid surface of the liquid mirror (4), is the rotational Gaussian deformation, is the two-dimensional coordinate on the cross section of the light beam, is the radius of the light beam at the position of the maximum light intensity.

8. The method of claim 7, wherein, The modulation phase of the light beam in the liquid mirror (4) is: ； wherein is the modulation phase at is the modulation phase at is the imaginary unit, is the wave vector.

9. The laser beam shaping method of claim 8, wherein, The reshaped light beam at the first position (701) is a plurality of ring structures after the light beam is focused by the lens (5), the first position (701) is the focal point of the lens (5), and the number of rings of the plurality of ring structures and the deformation amount height have the following relationship: ； wherein is the wavelength of the laser, is the number of rings of the multi-ring structure.

10. The method of laser beam shaping according to claim 9, wherein, The second position (702), the third position (703) and the fourth position (704) satisfy the following relationship: The second position (702) ranges between a position 0 behind the focal point of the lens (5), the third position (703) is a position behind the focal point of the lens (5), the fourth position (704) ranges between a position between 0.5 and 1.5 mm behind the focal point of the lens (5); wherein ; wherein is the analogous Rayleigh distance of the light beam after the focal point of the lens (5), which refers to the scale of the change in the shaped spot shape after the focal point of the lens (5), is the ring radius of the outermost ring structure.

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