Femtosecond laser processing device capable of realizing macro-micro-nano cross-scale surface structure

Abstract

The invention provides a femtosecond laser processing device capable of realizing a macro-micro-nano cross-scale surface structure, which is characterized in that a focused Gaussian laser and space shaping femtosecond laser collaborative processing light path device is designed based on a processing strategy of first rough processing and then fine processing, and Gaussian laser high-precision processing and space shaping surface light field efficient processing are integrated together, femtosecond laser can be shaped into a patterned light field through the spatial light modulator, cross-centimeter / micron scale efficient large-area patterned processing can be achieved, cross-micron / nano scale surface structure high-precision processing is achieved through Gaussian beams, and the high-efficiency and high-precision processing requirements of macro-micro-nano cross-scale structures can be met.

Description

Technical Field

[0001] The present invention belongs to the field of laser processing technology, and in particular relates to a femtosecond laser processing device capable of realizing macro-micro-nano cross-scale surface structures. Background Art

[0002] Macro-, micro-, and nanoscale surface structures are structures that integrate macroscopic, micron, and nanoscale features. Because they transcend the performance limitations of single-scale structures, they have become a cutting-edge research direction for researchers at home and abroad in recent years. They have shown great potential in functional device applications such as extreme wettability control, infrared anti-reflection, light absorption and thermal management, optical anti-counterfeiting, and drag reduction and energy saving. The preparation of macro-, micro-, and nanoscale surface structures is mostly achieved through processes such as optical lithography, electron beam lithography, and focused ion beam etching. These technologies either meet the processing accuracy requirements for micro- and nanostructures (e.g., electron beam lithography) but are too inefficient for macroscale processing; or they offer high processing efficiency (e.g., planar lithography) but lack micro- and nanoscale processing accuracy. Furthermore, the need for a vacuum environment, masks, complex processes, and high costs make it difficult to balance processing efficiency and accuracy, which is a bottleneck in current research in this field. Therefore, exploring how to achieve high-efficiency and high-precision processing of macro-, micro-, and nanoscale surface structures is of paramount importance.

[0003] Femtosecond laser has the unique advantages of being ultra-fast and ultra-strong. It can process any material under non-contact and mask-free conditions, and can realize the preparation of arbitrary geometric patterns. Its highly flexible processing methods and simple operation make this technology one of the most ideal manufacturing methods for macro-micro-nano cross-scale surface structures.

[0004] Currently, the main methods for processing cross-scale structures using femtosecond lasers include Gaussian laser point-by-point scanning, spatial shaping multi-focus / surface projection light field parallel processing, etc. The first method confines the femtosecond laser to an extremely small focal point, and uses the energy threshold effect during the interaction between the femtosecond laser and the material to make the processing area size close to or even exceed the optical diffraction limit, thereby achieving material processing accuracy from hundreds of nanometers to sub-micrometers, with high processing precision. However, during the focused Gaussian laser scanning process of cross-scale surface structures, the high-intensity energy areas of the laser focus need to have sufficient overlap to ensure continuous and uniform processing quality, resulting in low processing efficiency and a long time-consuming process when processing cross-scale structures of millimeter size and above. The second method shapes the femtosecond laser into a focused light field with multiple focal points, line spots, or patterned intensity distributions, removing a large amount of surface material at the micron / millimeter scale at one time, with processing efficiency far higher than Gaussian laser point-by-point scanning. However, by loading a phase map onto the SLM to modulate the intensity distribution of the light field in the focal plane, the resulting shaped light field often suffers from severe speckle noise. Speckle noise refers to irregularly distributed strong or dark energy spots, which reduces the edge precision of the shaped light field and makes it difficult to achieve submicron machining accuracy. Therefore, current femtosecond laser cross-scale machining methods do not yet meet the requirements for high-efficiency and high-precision machining of macro-, micro-, and nanoscale structures. Summary of the Invention

[0005] In order to solve the problem that the current femtosecond laser cross-scale processing method cannot meet the high-efficiency and high-precision processing requirements of macro-micro-nano cross-scale structures, the present invention provides a femtosecond laser processing device that can realize macro-micro-nano cross-scale surface structures, integrating Gaussian laser high-precision processing and spatial shaping surface light field high-efficiency processing, and can realize high-efficiency and high-precision processing of centimeter / micrometer / nanometer scale surface structures.

[0006] A femtosecond laser processing device capable of realizing macro-, micro-, and nanoscale surface structures includes a light source assembly, a beam splitter, a shaping and focusing assembly, a CCD camera, a control system, and a first processing channel and a second processing channel that operate independently of each other. The first processing channel includes a first mechanical shutter and a first ultrafast reflector, and the second processing channel includes a second mechanical shutter and a spatial light modulator.

[0007] The femtosecond laser emitted by the light source assembly is divided into two processing lasers after passing through a beam splitter, and the two processing lasers are incident on the first processing channel and the second processing channel respectively;

[0008] The CCD camera is used to monitor the processing process of the sample in real time and send the sample image to the control system;

[0009] The control system is used to open one of the mechanical shutters based on the matching relationship between the unprocessed area of the sample and the femtosecond laser spot. When the first mechanical shutter is opened, the processing laser is reflected by the first ultrafast reflector and sequentially passes through the beam splitter and the shaping and focusing component to be incident on the sample surface for processing; when the second mechanical shutter is opened, the control system is also used to select the hologram loaded on the spatial light modulator based on the matching relationship. The processing laser is modulated by the currently loaded hologram into a surface projection spot and then reflected back to the beam splitter, and then passes through the shaping and focusing component to be incident on the sample surface for processing.

[0010] Furthermore, the control system opens one of the mechanical shutters according to the matching relationship in the following specific method:

[0011] When the spot diameter of the femtosecond laser emitted by the light source assembly after focusing is at the nanometer level, and the area of the unprocessed area of the sample is at the centimeter level and micrometer level, the control system opens the second mechanical shutter; when the spot diameter of the femtosecond laser emitted by the light source assembly after focusing is at the nanometer level, and the area of the unprocessed area of the sample is at the nanometer level, the control system opens the first mechanical shutter.

[0012] Furthermore, the control system opens one of the mechanical shutters according to the matching relationship in the following specific method:

[0013] A determination is made as to whether the area of the unprocessed area is not larger than an order of magnitude greater than the spot area of the femtosecond laser emitted by the light source assembly. If so, the control system opens a first mechanical shutter; if not, the control system opens a second mechanical shutter, and at the same time, the control system adjusts the hologram loaded on the spatial light modulator so that the side length of the surface projection spot modulated by the currently loaded hologram is smaller than the maximum connecting distance corresponding to the unprocessed area; wherein the maximum connecting distance corresponding to the unprocessed area is: the farthest distance between any two points on the edge that encloses the shape of the unprocessed area.

[0014] Furthermore, the control system opens one of the mechanical shutters according to the matching relationship in the following specific method:

[0015] Obtaining the maximum line distance corresponding to the unprocessed area, wherein the maximum line distance corresponding to the unprocessed area is: the farthest distance between any two points on the edge that encloses the shape of the unprocessed area;

[0016] It is determined whether the minimum spot size of the surface projection spot that can be modulated by the hologram is smaller than the maximum connecting distance. If so, the control system opens the second mechanical shutter; if not, the control system opens the first mechanical shutter.

[0017] Furthermore, the control system opens one of the mechanical shutters according to the matching relationship in the following specific method:

[0018] When the unprocessed area is a polygon, the edge that is closest to the processing path is obtained from the edges that enclose the shape of the unprocessed area, and it is used as the reference edge for the subsequent processing path to refer to; at the same time, the edges connecting the two ends of the reference edge are used as neighbor edges;

[0019] The maximum line distance between the endpoint of the reference edge and the endpoint of any neighboring edge is obtained, and it is determined whether the maximum line distance is more than one order of magnitude greater than the spot diameter of the femtosecond laser emitted by the light source assembly. If so, the control system opens the first mechanical shutter; if not, the control system opens the second mechanical shutter, and at the same time, the control system adjusts the hologram loaded on the spatial light modulator so that the side length of the surface projection spot modulated by the currently loaded hologram is smaller than the maximum line distance.

[0020] Furthermore, the light source assembly includes a femtosecond laser, a half-wave plate, and a Glan prism placed in sequence along the optical path;

[0021] The femtosecond laser is used to emit femtosecond laser;

[0022] The half-wave plate and the Glan prism together constitute an energy adjustment module, and the energy adjustment module is used to adjust the energy of the femtosecond laser according to the required sample processing thickness.

[0023] Furthermore, the shaping and focusing assembly includes a second ultrafast reflector, a first plano-convex lens, a second plano-convex lens, a dichroic mirror, and a focusing objective lens sequentially placed along the optical path; wherein the first plano-convex lens and the second plano-convex lens together constitute a four-focal-length optical system;

[0024] The second ultrafast reflector is used to change the direction of the laser light emitted from the beam splitter so that it is incident on the four-focal-length optical system, which focuses and shapes the laser light field emitted from the beam splitter;

[0025] The dichroic mirror is used to synthesize laser light fields of different wavelengths after focusing and shaping to obtain a combined laser beam;

[0026] The focusing objective lens is used to focus the combined laser beam and make it incident on the sample surface.

[0027] Furthermore, the focusing objective lens is a 20x microscope objective lens, with a maximum entrance pupil diameter D of 8.1 mm, a maximum numerical aperture NAmax of 0.45, an equivalent focal length of 9 mm, and a working distance of 3.1 mm.

[0028] Furthermore, a femtosecond laser processing device capable of realizing macro-micro-nano cross-scale surface structures also includes a displacement platform for placing a sample;

[0029] The displacement platform is raised and lowered under the control of the control system so that the sample is located at the focus of the shaping and focusing component.

[0030] Furthermore, a femtosecond laser processing device capable of realizing macro-micro-nano cross-scale surface structures also includes a broadband light source;

[0031] The broadband light source is used to provide a CCD camera with an illumination light source for real-time monitoring of the processing process of the sample.

[0032] Beneficial effects:

[0033] 1. The present invention provides a femtosecond laser processing device that can realize macro-micro-nano cross-scale surface structures. Based on the rough-first-then-fine processing strategy, a focused Gaussian laser and spatially shaped femtosecond laser collaborative processing optical path device is designed to integrate Gaussian laser high-precision processing and spatially shaped surface light field efficient processing. Among them, the femtosecond laser can be shaped into a patterned light field through a spatial light modulator, which can realize efficient large-area patterned processing across centimeter / micrometer scales, and high-precision processing of micron / nanometer scale surface structures can be achieved through Gaussian beams, which can meet the high-efficiency and high-precision processing requirements of macro-micron-nano cross-scale structures.

[0034] 2. The present invention provides a femtosecond laser processing device that can realize macro-micro-nano cross-scale surface structures. It uses spatially shaped femtosecond laser to adjust the incident laser into a millimeter-sized patterned light field, and quickly realizes large-area material removal across the centimeter / micrometer scale on the sample surface to form a rough-processed cross-scale surface structure blank; it uses focused Gaussian laser to fine-tune the local fine areas of the cross-scale surface structure and compensate for the rough edges left by the rough processing, meeting the sub-micron or even hundred-nanometer processing accuracy requirements, and ultimately realizing high-efficiency and high-precision processing of macro-micro-nano cross-scale surface structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A schematic diagram of the optical path of a femtosecond laser processing device provided by the present invention that can realize macro-micro-nano scale surface structures;

[0036] Figure 2 The schematic diagram of the high-efficiency and high-precision processing principle of macro-micro-nano cross-scale surface structures provided by the present invention;

[0037] 1-Femtosecond laser, 2-Half wave plate, 3-Glan prism, 4-Beam splitter, 5-First mechanical shutter, 6-First ultrafast mirror, 7-Second mechanical shutter, 8-Spatial light modulator (SLM), 9-Second ultrafast mirror, 10-First plano-convex lens, 11-Second plano-convex lens, 12-CCD camera, 13-Dichroic mirror, 14-Focusing objective, 15-Sample, 16-High-precision translation stage, 17-Broadband light source, 18-Control system. DETAILED DESCRIPTION

[0038] In order to enable people skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0039] Based on a rough-first, fine-finishing machining strategy, this invention designs a collaborative optical path device for machining with a focused Gaussian laser and a spatially shaped femtosecond laser. Using the spatially shaped femtosecond laser, the incident laser is adjusted to a millimeter-sized patterned light field, rapidly removing large areas of material across centimeters and micrometers on the sample surface, forming a rough-machined, cross-scale surface structure blank. Subsequently, a focused Gaussian laser is used to fine-tune localized microscopic areas of the cross-scale surface structure, compensating for the rough edges left by the rough machining. This achieves submicron and even hundred-nanometer machining precision requirements, ultimately enabling efficient and high-precision manufacturing of macro-, micro-, and nanoscale cross-scale surface structures.

[0040] Specifically, the present invention provides a femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures, comprising a light source assembly, a beam splitter 4, a shaping and focusing assembly, a CCD camera 12, a control system 18, and a first processing channel and a second processing channel that operate independently of each other; wherein the first processing channel comprises a first mechanical shutter 5 and a first ultrafast reflector 6, and the second processing channel comprises a second mechanical shutter 7 and a spatial light modulator 8;

[0041] The femtosecond laser emitted by the light source assembly is divided into two processing lasers after passing through a beam splitter, and the two processing lasers are incident on the first processing channel and the second processing channel respectively;

[0042] The CCD camera 12 is used to monitor the processing process of the sample 15 in real time and send the sample image to the control system 18;

[0043] The control system 18 is used to open one of the mechanical shutters according to the matching relationship between the unprocessed area of the sample and the femtosecond laser spot. When the first mechanical shutter 5 is opened, the processing laser is reflected by the first ultrafast reflector 6 and is sequentially incident on the surface of the sample 15 through the beam splitter 4 and the shaping and focusing component for processing; when the second mechanical shutter 7 is opened, the control system 18 is also used to select the hologram loaded on the spatial light modulator 8 according to the matching relationship. The processing laser is modulated by the currently loaded hologram into a surface projection spot and then reflected back to the beam splitter 4, and then is incident on the sample surface through the shaping and focusing component for processing.

[0044] It should be noted that the first method for the control system to open one of the mechanical shutters according to the matching relationship is specifically:

[0045] When the spot diameter of the femtosecond laser emitted by the light source assembly after focusing is at the nanometer level, and the area of the unprocessed area of the sample is at the centimeter level and the micrometer level, the control system opens the second mechanical shutter 7; when the spot diameter of the femtosecond laser emitted by the light source assembly after focusing is at the nanometer level, and the area of the unprocessed area of the sample is at the nanometer level, the control system opens the first mechanical shutter 5.

[0046] The second method of the control system opening one of the mechanical shutters according to the matching relationship is as follows:

[0047] It is determined whether the area of the unprocessed area is not more than one order of magnitude larger than the spot area of the femtosecond laser emitted by the light source assembly. If so, the control system opens the first mechanical shutter 5; if not, the control system opens the second mechanical shutter 7. At the same time, the control system adjusts the hologram loaded on the spatial light modulator so that the side length of the surface projection spot modulated by the currently loaded hologram is smaller than the maximum connecting distance corresponding to the shape of the unprocessed area; wherein the maximum connecting distance corresponding to the shape of the unprocessed area is: the farthest distance between any two points on the edge that encloses the shape of the unprocessed area.

[0048] The third method for the control system to open one of the mechanical shutters according to the matching relationship is as follows:

[0049] Obtaining a maximum line distance corresponding to the unprocessed area, wherein the maximum line distance corresponding to the unprocessed area is: the farthest distance between any two points on the edge that encloses the shape of the unprocessed area; determining whether a minimum spot size of a surface projection spot that can be modulated by the hologram is smaller than the maximum line distance; if so, controlling the control system to open the second mechanical shutter; if not, controlling the control system to open the first mechanical shutter.

[0050] The fourth method for the control system to open one of the mechanical shutters according to the matching relationship is as follows:

[0051] When the unprocessed area is a polygon, the edge that is closest to the processing path is obtained from the edges that enclose the shape of the unprocessed area, and it is used as the reference edge for the subsequent processing path to refer to; at the same time, the edges connecting the two ends of the reference edge are used as neighbor edges;

[0052] The maximum line distance between the endpoint of the reference edge and the endpoint of any neighboring edge is obtained, and it is determined whether the maximum line distance is more than one order of magnitude greater than the spot diameter of the femtosecond laser emitted by the light source assembly. If so, the control system opens the first mechanical shutter 5; if not, the control system opens the second mechanical shutter 7, and at the same time, the control system adjusts the hologram loaded on the spatial light modulator so that the side length of the surface projection spot modulated by the currently loaded hologram is smaller than the maximum line distance.

[0053] Further, if Figure 1 As shown, the light source assembly includes a femtosecond laser 1, a half-wave plate 2, and a Glan prism 3 placed in sequence along the optical path; the shaping and focusing assembly includes a second ultrafast reflector 9, a first plano-convex lens 10, a second plano-convex lens 11, a dichroic mirror 13, and a focusing objective lens 14 placed in sequence along the optical path; wherein the first plano-convex lens 10 and the second plano-convex lens 11 together constitute a four-focal-length optical system; the femtosecond laser processing device also includes a displacement platform 16 and a broadband light source 17;

[0054] The femtosecond laser is used to emit femtosecond laser;

[0055] The half-wave plate and the Glan prism together constitute an energy adjustment module, which is used to adjust the energy of the femtosecond laser according to the required sample processing thickness;

[0056] Two mechanical shutters are used to filter out stray light from the adjusted processing laser and also serve as switches for the optical path;

[0057] The second ultrafast reflector is used to change the direction of the laser light emitted from the beam splitter so that it is incident on the four-focal-length optical system, which focuses and shapes the laser light field emitted by the beam splitter. In other words, the ultrafast reflector is used to change the direction of the light path; the spatial light modulator adjusts the pattern of the laser beam by loading different holograms to achieve large-area surface projection processing; the two plano-convex lenses act as a four-focal-length optical system (4f system) to transport the spatially light modulated light field;

[0058] The dichroic mirror is used to synthesize laser light fields of different wavelengths after focusing and shaping to obtain a combined laser beam;

[0059] The focusing objective lens is used to focus the combined laser beam and make it incident on the sample surface; optionally, the focusing objective lens is a 20x microscope objective lens, which has a maximum entrance pupil diameter D of 8.1 mm, a maximum numerical aperture NAmax of 0.45, an equivalent focal length of 9 mm, and a working distance of 3.1 mm;

[0060] The displacement platform is used to place the sample and is raised and lowered under the control of the control system to flexibly adjust the processing position so that the sample is located at the focus of the shaping and focusing assembly;

[0061] The broadband light source is used to provide a CCD camera with an illumination light source for real-time monitoring of the processing process of the sample.

[0062] That is to say, the femtosecond laser of the present invention emits femtosecond pulses that pass through the energy regulation device in sequence, and the femtosecond laser is shaped into a patterned light field through the spatial light modulator. The patterned light field is transported by the 4f system and irradiated on the surface of the material placed on the high-precision displacement platform, thereby realizing the processing of large-area patterned microstructures, and the large-area patterned microstructures are subjected to secondary fine modification by Gaussian laser; the broadband light source irradiates the sample surface through the beam splitter, dichroic mirror and focusing objective lens in sequence, and then the reflected light returns along the original path and passes through the beam splitter to enter the CCD camera, thereby realizing real-time monitoring of the processing process.

[0063] The following is a specific process of performing cross-scale surface structure processing using the femtosecond laser processing device of the present invention:

[0064] like Figure 2 As shown, rough machining of the cross-scale patterned structure is first performed. The first mechanical shutter 5 is closed, the second mechanical shutter 7 is opened, and the Gaussian laser is shaped into a planar projection spot by the spatial light modulator 8. This spot is focused by the focusing and shaping component and then acts on the sample 15. During the rough machining process, the CCD camera 12 is used to observe the machining process in real time. The machining path is usually to process one row from left to right, then switch to the next row from right to left, in an efficient, continuous manner. When processing from one end of the pattern to the other end, observe the connecting line distance between adjacent edge endpoints of the pattern. The maximum connecting line distance is more than one order of magnitude greater than the spot diameter of the femtosecond laser emitted by the light source component, but the side length of the surface projection spot at this time is greater than the said maximum connecting line distance. Obviously, the surface projection spot at this time is obviously not matched with the edge of the unprocessed area. Close the second mechanical shutter 7, load the spatial light modulator 8 with a hologram that can produce a smaller shaping spot, and then open the second mechanical shutter 7 to use the smaller spot to process the pattern edge; however, when the maximum connecting line distance is more than one order of magnitude greater than the spot diameter of the femtosecond laser emitted by the light source component, but the side length of the surface projection spot at this time is also much smaller than the said maximum connecting line distance, in order to improve the processing efficiency, close the mechanical shutter 7, load the spatial light modulator 8 with a hologram that can produce a larger shaping spot, and use the larger shaping spot to process the pattern edge, and repeat this large-area processing. During real-time observation, if it is found that the maximum connecting distance is not more than an order of magnitude greater than the spot diameter of the femtosecond laser emitted by the light source assembly or the minimum spot size after shaping by the spatial light modulator is greater than the maximum connecting distance, it is necessary to close the first mechanical shutter 7 and open the second mechanical shutter 5, and use the high precision of the Gaussian laser to perform processing of extremely small and subtle details, thereby achieving high-precision processing of cross-scale surface structures.

[0065] For example, the processing pattern is a quadrilateral, with vertices A, B, C, and D, and four sides AB, BC, CD, and DA. The actual path starts from point A along the AB side. When it is almost at point B, if the distance between the A end point and the B end point of the AB and BC sides is smaller than the side length of the processed surface projection spot, that is, it is obviously mismatched with the edge of the processed pattern structure, the first mechanical shutter 7 is closed, the hologram is adjusted, and the surface projection spot is reduced. When the minimum spot size after shaping by the spatial light modulator is larger than the distance between the A end point and the B end point, the second mechanical shutter 5 is opened to use the high precision of the Gaussian laser to perform extremely fine processing.

[0066] In summary, the present invention designs a focused Gaussian laser and spatially shaped femtosecond laser collaborative processing optical path device. The femtosecond laser can be shaped into a patterned light field through a spatial light modulator, which can realize efficient large-area patterning processing across centimeter / micrometer scales, and high-precision processing of surface structures across micrometer / nanometer scales can be achieved through Gaussian beams. That is, the present invention can realize high-efficiency and high-precision processing of surface structures across centimeter / micrometer / nanometer scales.

[0067] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may of course make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures, characterized in that: The device comprises a light source assembly, a beam splitter, a shaping and focusing assembly, a CCD camera, a control system, and a first processing channel and a second processing channel that operate independently of each other; wherein the first processing channel comprises a first mechanical shutter and a first ultrafast reflector, and the second processing channel comprises a second mechanical shutter and a spatial light modulator; The femtosecond laser emitted by the light source assembly is divided into two processing lasers after passing through a beam splitter, and the two processing lasers are incident on the first processing channel and the second processing channel respectively; The CCD camera is used to monitor the processing process of the sample in real time and send the sample image to the control system; The control system is used to open one of the mechanical shutters based on the matching relationship between the unprocessed area of the sample and the femtosecond laser spot. When the first mechanical shutter is opened, the processing laser is reflected by the first ultrafast reflector and sequentially passes through the beam splitter and the shaping and focusing component to be incident on the sample surface for processing; when the second mechanical shutter is opened, the control system is also used to select the hologram loaded on the spatial light modulator based on the matching relationship. The processing laser is modulated by the currently loaded hologram into a surface projection spot and then reflected back to the beam splitter, and then passes through the shaping and focusing component to be incident on the sample surface for processing.

2. A femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: The method for the control system to open one of the mechanical shutters according to the matching relationship is as follows: When the spot diameter of the femtosecond laser emitted by the light source assembly after focusing is at the nanometer level, and the area of the unprocessed area of the sample is at the centimeter level and micrometer level, the control system opens the second mechanical shutter; when the spot diameter of the femtosecond laser emitted by the light source assembly after focusing is at the nanometer level, and the area of the unprocessed area of the sample is at the nanometer level, the control system opens the first mechanical shutter.

3. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: The method for the control system to open one of the mechanical shutters according to the matching relationship is as follows: A determination is made as to whether the area of the unprocessed area is not larger than an order of magnitude greater than the spot area of the femtosecond laser emitted by the light source assembly. If so, the control system opens a first mechanical shutter; if not, the control system opens a second mechanical shutter, and at the same time, the control system adjusts the hologram loaded on the spatial light modulator so that the side length of the surface projection spot modulated by the currently loaded hologram is smaller than the maximum connecting distance corresponding to the unprocessed area; wherein the maximum connecting distance corresponding to the unprocessed area is: the farthest distance between any two points on the edge that encloses the shape of the unprocessed area.

4. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: The method for the control system to open one of the mechanical shutters according to the matching relationship is as follows: Obtaining the maximum line distance corresponding to the unprocessed area, wherein the maximum line distance corresponding to the unprocessed area is: the farthest distance between any two points on the edge that encloses the shape of the unprocessed area; It is determined whether the minimum spot size of the surface projection spot that can be modulated by the hologram is smaller than the maximum connecting distance. If so, the control system opens the second mechanical shutter; if not, the control system opens the first mechanical shutter.

5. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: The method for the control system to open one of the mechanical shutters according to the matching relationship is as follows: When the unprocessed area is a polygon, the edge that is closest to the processing path is obtained from the edges that enclose the shape of the unprocessed area, and it is used as the reference edge for the subsequent processing path to refer to; at the same time, the edges connecting the two ends of the reference edge are used as neighbor edges; The maximum line distance between the endpoint of the reference edge and the endpoint of any neighboring edge is obtained, and it is determined whether the maximum line distance is more than one order of magnitude greater than the spot diameter of the femtosecond laser emitted by the light source assembly. If so, the control system opens the first mechanical shutter; if not, the control system opens the second mechanical shutter, and at the same time, the control system adjusts the hologram loaded on the spatial light modulator so that the side length of the surface projection spot modulated by the currently loaded hologram is smaller than the maximum line distance.

6. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: The light source assembly includes a femtosecond laser, a half-wave plate, and a Glan prism placed in sequence along the optical path; The femtosecond laser is used to emit femtosecond laser; The half-wave plate and the Glan prism together constitute an energy adjustment module, and the energy adjustment module is used to adjust the energy of the femtosecond laser according to the required sample processing thickness.

7. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: The shaping and focusing assembly comprises a second ultrafast reflector, a first plano-convex lens, a second plano-convex lens, a dichroic mirror, and a focusing objective lens, which are sequentially placed along the optical path; wherein the first plano-convex lens and the second plano-convex lens together form a four-focal-length optical system; The second ultrafast reflector is used to change the direction of the laser light emitted from the beam splitter so that it is incident on the four-focal-length optical system, which focuses and shapes the laser light field emitted from the beam splitter; The dichroic mirror is used to synthesize laser light fields of different wavelengths after focusing and shaping to obtain a combined laser beam; The focusing objective lens is used to focus the combined laser beam and make it incident on the sample surface.

8. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 7, characterized in that: The focusing objective lens is a 20x microscope objective lens, with a maximum entrance pupil diameter D of 8.1 mm, a maximum numerical aperture NAmax of 0.45, an equivalent focal length of 9 mm, and a working distance of 3.1 mm.

9. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: It also includes a displacement platform for placing samples; The displacement platform is raised and lowered under the control of the control system so that the sample is located at the focus of the shaping and focusing component.

10. The femtosecond laser processing device capable of realizing macro-micro-nano scale surface structures according to claim 1, characterized in that: Also included are broadband light sources; The broadband light source is used to provide a CCD camera with an illumination light source for real-time monitoring of the sample processing process.

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