Method and system for laser internal engraving of transparent materials

Abstract

The application discloses a transparent material laser internal engraving method and system, and belongs to the technical field of laser processing. The method imports pattern data to be internally engraved, and obtains the overall Z direction span of the pattern and the geometric data distribution characteristics along the Z axis direction through analysis; a wire forming processing head with appropriate focal depth is selected according to the total thickness of the transparent material to be processed; the pattern data is adaptively layered based on the focal depth of the wire forming processing head and the geometric data distribution characteristics; for each layer, the laser focal point is locked to the reference depth; then during the XY plane scanning process, the Z axis is driven to continuously zoom within the layer in real time; the wire forming effect of the ultrafast laser is utilized to construct a continuous modification channel during the process; and zooming between layers is performed when the layers are switched. The wire-shaped modification channel engraved by the scheme of the application presents a real continuous curved surface and longitudinal structure in the material interior, and has excellent three-dimensional suspension and entity feeling when viewed from multiple angles.

Description

Technical Field

[0001] This invention relates to the field of laser processing technology, and in particular to a method and system for laser engraving of transparent materials. Background Technology

[0002] Internal laser engraving technology for transparent materials such as glass, crystal, and acrylic, or simply "laser internal engraving," works by focusing a high-energy-density laser beam inside the material. Through nonlinear absorption, micro-explosion points or modified areas are created at the focal point, forming visible three-dimensional patterns. With the increasing demand for personalized customization and high-end decoration, higher requirements are being placed on the complexity, visual effects, and processing efficiency of internally engraved graphics.

[0003] Existing laser engraving techniques for transparent materials, whether using 2D galvanometers with planar filling or 3D motion axes or 3D dynamic focusing galvanometers for spatial scanning, all rely on a single-point explosion mode as their core imaging mechanism. This means controlling the laser to trigger micro-explosions point-by-point within the material, simulating three-dimensional graphics through the spatial accumulation of discrete points. Figure 1 This is a schematic diagram of the single-point burst engraving effect in existing technology. This existing technology based on single-point bursting has the following significant drawbacks: (1) The imaging structure is discrete and lacks a sense of depth. For example... Figure 1 As shown, the imaging unit of the existing technology is an independent micro-explosion point, which results in a blurry, three-dimensional image that is poorly viewed from multiple angles.

[0004] (2) Severe heat accumulation leads to a contradiction between processing efficiency and material safety. To compensate for the sparseness of single-point imaging and improve brightness, existing technologies often require increasing the dot density or performing multiple repeated scans. This high-frequency pulse effect not only significantly reduces processing efficiency but also causes heat to accumulate rapidly inside the material. Excessive heat accumulation can alter the local stress distribution of the material, easily triggering microcrack propagation or even causing the entire material to break apart, thus limiting the processing parameter window and yield.

[0005] (3) High equipment cost or limited functionality. In order to achieve 3D internal carving with a sense of depth, existing technologies usually rely on expensive 3D dynamic focusing galvanometer systems to achieve rapid zooming; if low-cost mechanical axis movement or ordinary cutting equipment is used, it is limited by the inefficiency of single-point bursting and the lack of software-controlled dynamic zooming capabilities, making it difficult to achieve continuous changes in the depth of the focus in a single processing, and thus unable to efficiently construct complex graphics with a sense of three-dimensional layering.

[0006] In summary, existing technologies, limited by the imaging principle of single-point bursting, have been unable to solve the problems of lack of three-dimensionality in internally carved graphics, high risk of thermal damage, and difficulty in balancing equipment cost and performance. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a method and system for laser engraving of transparent materials, addressing the above-mentioned deficiencies of the prior art.

[0008] To achieve the above objectives, the present invention provides a method for laser engraving of transparent materials, comprising the following steps: Step S1: Import the graphic data to be engraved and parse it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; among which, Defined as the difference between the maximum and minimum depth coordinates in the graphic data; the geometric data distribution characteristics include the connectivity distribution of the graphic data in the Z-axis direction and the Z-axis span of the effective data segment; Step S2: A filamentation head with a focal depth matching the total thickness of the transparent material to be processed is selected to ensure that the material surface is not damaged during processing; the effective focal depth of the filamentation head is... ; Step S3: Based on The geometric data distribution characteristics are used to adaptively layer the graphic data to generate a processing sequence containing multiple process processing layers, and a corresponding scanning path is planned for each process processing layer. Step S4: For each of the process layers, firstly control the laser focus to lock the static reference depth; then, during the XY plane scanning process, drive the Z axis in real time to make the laser focus follow the three-dimensional undulations of the graphic surface for dynamic fine adjustment, so as to realize continuous zoom within the layer; during this process, the filamentation effect of ultrafast laser is used to construct a continuous modification channel; and depth transition and interlayer overlap are performed when switching between layers to realize interlayer zoom.

[0009] In the transparent material laser engraving method of the present invention, step S4 includes: The transparent material is fixed on a motion platform with X, Y, and Z axis linkage function, keeping the spatial position of the filament processing head and its internal optical focus relatively stationary; For each processing layer, calculate its reference depth coordinates. The motion platform is controlled to move the transparent material along the Z-axis, aligning the target processing area on the material surface with the optical focal point to complete the reference positioning. Real-time calculation of each point on the scan path relative to depth offset It generates Z-axis micro-motion commands that are strictly time-synchronized with the X and Y axis movements, driving the motion platform to produce displacement in the vertical direction. This allows the patterned surfaces at different depths within the material to pass sequentially through the stationary optical focal point, thereby achieving real-time zooming within the layer. Simultaneously, by controlling the output pulse train of an ultrafast laser with specific parameters, a continuous filamentary modified channel is formed inside the material using the nonlinear self-focusing effect. When switching between adjacent processing layers, the software controls the motion platform to quickly move the transparent material to the reference depth position of the next layer, and achieves seamless splicing of the modified channel through the preset interlayer overlap area.

[0010] In the transparent material laser engraving method of the present invention, in step S4, the Z-axis span of the interlayer overlap region is... to .

[0011] In the transparent material laser engraving method of the present invention, the adaptive layering in step S3 includes: Based on the effective depth of the filament processing head Set the maximum allowable thickness of a single layer Where k is a preset coefficient, with a value ranging from 0.8 to 1.2; Analyze the geometric data distribution characteristics to identify all valid data segments containing geometric information; for each valid data segment, if its Z-axis span does not exceed... If the valid data segment is directly defined as a single processing layer, then the valid data segment is subdivided into multiple processing layers along the Z-axis, such that the Z-axis span of each processing layer does not exceed [a certain value]. The final list of process layers is then generated.

[0012] In the transparent material laser engraving method of the present invention, the ultrafast laser parameters used in step S4 are set as follows: Use picosecond or femtosecond lasers; Enable Burst mode, where each pulse train contains 2 to 10 sub-pulses; The laser repetition frequency is set to 100kHz to 1000kHz; The single-pulse output energy is 100μJ to 200μJ.

[0013] In the transparent material laser engraving method of the present invention, in step S2, the effective focal depth of the filament processing head... Meet safety constraints: ;in, This is the sum of the preset safety thresholds for the upper and lower surfaces; This represents the total thickness of the transparent material to be processed.

[0014] The present invention also provides a transparent material laser engraving system for performing the transparent material laser engraving method as described above, the system comprising: Ultrafast laser processing unit: includes an ultrafast laser and a filamentation head, the filamentation head having a defined effective depth of focus. It is used to excite a nonlinear self-focusing effect inside transparent materials to form filament-modified channels; Multi-axis motion platform: It has X, Y and Z three-axis linkage function and is used to carry and drive the transparent material to be processed to move in three-dimensional space; Data processing and control unit: electrically connected to the ultrafast laser processing unit and multi-axis motion platform, running laser engraving software configured to perform the following operations: Data Analysis: Import the graphic data to be engraved and analyze it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; among which, Defined as the difference between the maximum and minimum depth coordinates in the graphic data; Parameter matching: Obtain the total thickness of the transparent material to be processed. and in accordance with safety constraints Verify or select the filament processing head; wherein, This is the sum of the preset safety thresholds for the upper and lower surfaces; Adaptive hierarchical structure: based on The geometric data distribution characteristics are used to adaptively layer the graphic data to generate a processing sequence containing multiple process processing layers, and a corresponding scanning path is planned for each process processing layer. Dynamic zoom control: For each of the aforementioned process layers, the multi-axis motion platform is controlled to first move the material to the static reference depth position; then, during the XY plane scanning process, the Z axis is driven in real time to make the material follow the three-dimensional undulations of the graphic surface for dynamic fine adjustment, thereby achieving continuous zoom within the layer; and depth transition and interlayer overlap are performed when switching between layers to achieve interlayer zoom.

[0015] In the transparent material laser engraving system of the present invention, the data processing and control unit is specifically configured to perform the dynamic zoom control as follows: The spatial position of the filament forming head and its internal optical focal point remains relatively stationary; For each processing layer, calculate its reference depth coordinates. The multi-axis motion platform is controlled to move the transparent material in the Z-axis direction, so that the target processing area on the material surface is aligned with the optical focal point, thus completing the reference positioning; Real-time calculation of each point on the scan path relative to depth offset It generates Z-axis micro-motion commands that are strictly time-synchronized with the X and Y axis movements, driving the multi-axis motion platform to produce displacement in the vertical direction. This allows the patterned surfaces at different depths within the material to pass sequentially through the stationary optical focal point. The ultrafast laser is controlled to output pulse trains with specific parameters to form a continuous filamentary modified channel by utilizing the nonlinear self-focusing effect; When switching between adjacent processing layers, the multi-axis motion platform is controlled to quickly move the transparent material to the reference depth position of the next layer, and the modified channel is seamlessly spliced ​​through the preset interlayer overlap area.

[0016] In the transparent material laser engraving system of the present invention, the data processing and control unit is configured to set the Z-axis span of the interlayer overlap region as... to .

[0017] In the transparent material laser engraving system of the present invention, the data processing and control unit is specifically configured to perform the adaptive layering as follows: Based on the effective depth of the filament processing head Set the maximum allowable thickness of a single layer Where k is a preset coefficient, with a value ranging from 0.8 to 1.2; Analyze the geometric data distribution characteristics to identify all valid data segments containing geometric information; For each valid data segment: if its Z-axis span does not exceed If the valid data segment is directly defined as a single processing layer, then the valid data segment is subdivided into multiple processing layers along the Z-axis, such that the Z-axis span of each processing layer does not exceed [a certain value]. ; The final list of process layers is then generated.

[0018] In the transparent material laser engraving system of the present invention, the ultrafast laser is a picosecond laser or a femtosecond laser; The ultrafast laser is in Burst mode, and each pulse train contains 2 to 10 sub-pulses; The laser repetition frequency is set to 100kHz to 1000kHz; The single-pulse output energy is 100μJ to 200μJ.

[0019] The present invention has the following beneficial effects: The present invention imports the graphic data to be engraved and analyzes it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; based on A filamentation head with a suitable focal depth is selected based on the total thickness of the transparent material to be processed. The graphic data is adaptively layered based on the focal depth and geometric data distribution characteristics of the filamentation head. For each layer, the laser focus is controlled to lock the static reference depth. Subsequently, during XY plane scanning, the Z-axis is driven in real-time for continuous zooming within the layer. During this process, the filamentation effect of ultrafast lasers is used to construct continuous modified channels. Interlayer zooming is performed when switching between layers. This invention replaces the single-point bursting filamentation method with filamentation engraving, resulting in filamentous modified channels that present a realistic continuous curved surface and depth structure within the material, providing excellent three-dimensional suspension and solidity when viewed from multiple angles. Furthermore, compared to the multiple-dot filling method of single-point filling, using filamentation processing allows for fewer laser processing steps to achieve the desired image effect, reducing heat buildup. When applied to watch cover plates, the breakage rate is reduced by 20%, improving product yield. The solution of using a fixed optical path and a moving workpiece eliminates the need for expensive and complex 3D dynamic focusing galvanometers. It only requires a standard three-axis motion platform with high-precision control algorithms to achieve the same or even better dynamic zoom effect, which greatly reduces the hardware cost of the equipment. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the single-point bursting internal carving effect of existing technology.

[0021] Figure 2 This is a schematic diagram illustrating the steps of a laser engraving method for transparent materials provided in an embodiment of the present invention.

[0022] Figure 3 An example of a graphic to be engraved is provided for an embodiment of the present invention.

[0023] Figure 4 This is a schematic diagram illustrating the principle of laser filament engraving in an embodiment of the present invention.

[0024] Figure 5 The image shows the effect of laser filament engraving in an embodiment of the present invention.

[0025] Figure 6 This is a schematic diagram of the transparent material laser engraving system provided in an embodiment of the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] The embodiments of the present invention will now be described in further detail with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the invention.

[0028] like Figure 2 As shown, this invention provides a laser engraving method for transparent materials. This method is applicable to transparent substrates such as glass, crystal, and acrylic, especially workpieces with specific thickness requirements, such as crystal watch dial covers. This method is particularly suitable for 3D graphic data with depth variations, achieving a significant sense of three-dimensional layering. Of course, this method is also compatible with traditional 2D graphic data. When the input is a 2D graphic, the Z-axis is not dynamically modulated, and the resulting pattern is a planar structure, with a less pronounced sense of three-dimensional layering than 3D graphics. However, this does not affect the execution flow of this method. This method includes the following steps: Step S1: Import the graphic data to be engraved and parse it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; among which, Defined as the difference between the maximum and minimum depth coordinates in the graphic data; the geometric data distribution characteristics include the connectivity distribution of the graphic data in the Z-axis direction and the Z-span of the effective data segment.

[0029] Before laser engraving, you need to use graphic design software to design the 2D or 3D graphic to be engraved, save the graphic in a format that the laser control software can recognize, and then import the graphic into the laser control software to parse and obtain the specific information of the graphic. Figure 3 This is an example of a graphic to be engraved in an embodiment of the present invention. Specifically, it is a 3D stereoscopic image of a snowflake pattern created for a crystal dial cover with a thickness of 3mm. There are a total of 6 snowflake segments, randomly distributed along the thickness direction. The difference between the maximum and minimum depth coordinates of the snowflake segments is 1mm. Therefore, =1mm.

[0030] Step S2: A filamentation head with a focal depth matching the total thickness of the transparent material to be processed is selected to ensure that the material surface is not damaged during processing; the effective focal depth of the filamentation head is... Effective depth of focus of the filament forming head Meet safety constraints: ;in, This is the sum of the preset safety thresholds for the upper and lower surfaces; This represents the total thickness of the transparent material to be processed.

[0031] This represents the minimum buffer distance between the depth range that the laser focus can reach and the physical boundary of the material, achieved by setting... This effectively prevents the laser beam's tail from extending beyond the surface of transparent materials, thus preventing the formation of noticeable pits, cracks, or rough marks that could directly lead to product failure. Furthermore, setting... It can also compensate for mechanical motion errors and material thickness tolerances, ensuring that laser processing cannot damage the material surface within the allowable tolerance range. Furthermore, when lasers modify the material internally, they generate localized thermal stress. If the modified area is too close to the surface, this stress wave, when propagated to the free surface, can easily induce the propagation of surface microcracks, or even lead to edge chipping. It is the sum of the safety distances of the upper and lower surfaces, and its specific value depends on the material type, processing precision, laser energy, and depth of focus. In this embodiment of the invention, the sum of the safety thresholds of the upper and lower surfaces... The value ranges from 0.2 mm to 1.0 mm. Preferably, The value is determined based on the effective focal depth of the filament forming head. Dynamic adjustment. Alternatively, adjustment can be made based on the material of the object being processed; for example, when processing an optically transparent material, the settings can be adjusted accordingly. Not less than 0.4mm; when the processed object is a common decorative transparent material and the material thickness is greater than 5mm, It can be set to 0.3mm. Figure 3 The corresponding thickness of the transparent material to be carved internally It is 3mm. =1mm, the effective focal depth of the wire forming head selected during actual processing is 1mm. =0.4mm.

[0032] Step S3: Based on The graphic data is adaptively layered based on the geometric data distribution characteristics to generate a processing sequence containing multiple processing layers, and a corresponding scanning path is planned for each processing layer. The adaptive layering includes: based on the effective depth of focus of the filament forming head... Set the maximum allowable thickness of a single layer Where k is a preset coefficient, with a value ranging from 0.8 to 1.2; analyze the geometric data distribution characteristics to identify all valid data segments containing geometric information; for each valid data segment, if its Z-axis span does not exceed If the valid data segment is directly defined as a single processing layer, then the valid data segment is subdivided into multiple processing layers along the Z-axis, such that the Z-axis span of each processing layer does not exceed [a certain value]. The final list of process layers is then generated.

[0033] In this embodiment of the invention, the geometric data distribution characteristics are analyzed to identify all valid data segments containing geometric information. Then, only the valid data segments are layered, automatically skipping blank segments, thus improving the efficiency of subsequent laser engraving. The length of the filamentous modified channel formed by the filamentation head is limited; only within the depth of focus is the laser energy density sufficient to excite the nonlinear self-focusing effect, forming a continuous, high-brightness white filamentous structure. A maximum allowable thickness for a single layer is set. The fundamental function is to adapt the geometric features of the image to the physical limits of laser processing, ensuring that the processing of each layer is carried out within the optimal depth of focus of the filamentation head. This avoids focus mismatch or insufficient energy density caused by improper layer thickness settings, guaranteeing the consistency of the filamentation effect across the entire image. The adaptive layering process in this embodiment is no longer a blind, equally spaced slice, but rather an intelligent decision based on the actual geometric distribution characteristics of the image and processing capabilities. It maximizes the processing volume of a single layer while ensuring quality, balancing efficiency and quality. The maximum allowable thickness of a single layer is set. The value of k ranges from 0.8 to 1.2 to address the complexity of actual processes. k < 1 is suitable for high-precision, highly curved areas, allowing for more depth-of-focus margin to ensure perfect filamentation at the edges even with mechanical errors or changes in material refractive index, pursuing ultimate quality. k > 1 is suitable for flat, simple areas, utilizing the characteristic that while the depth-of-focus edge is slightly weaker, it is still acceptable to appropriately increase the layer thickness and reduce the total number of layers, pursuing processing efficiency. In this embodiment of the invention, for Figure 3 Based on the Z-axis position distribution of each snowflake fragment, it is divided into six processing layers, each containing one snowflake fragment.

[0034] In some embodiments of the present invention, the specific method for planning the corresponding scanning path for each of the process layers is as follows: analyze the geometric data distribution characteristics of the layer to identify steep regions and flat regions with drastic depth changes; according to the regional characteristics, a partitioned hybrid strategy is adopted for planning: contour offset scanning or high-density raster scanning is used for steep regions, and high-speed filling scanning is used for flat regions.

[0035] Step S4: For each of the process layers, firstly control the laser focus to lock the static reference depth; then, during the XY plane scanning process, drive the Z axis in real time to make the laser focus follow the three-dimensional undulations of the graphic surface for dynamic fine adjustment, so as to realize continuous zoom within the layer; during this process, the filamentation effect of ultrafast laser is used to construct a continuous modification channel; and depth transition and interlayer overlap are performed when switching between layers to realize interlayer zoom.

[0036] In this embodiment of the invention, step S4 includes: fixing the transparent material on a motion platform with X, Y, and Z axis linkage function, keeping the spatial position of the filamentation head and its internal optical focal point relatively stationary. For each processing layer, its reference depth coordinates are calculated. The motion platform is controlled to move the transparent material along the Z-axis, aligning the target processing area on the material surface with the optical focal point, thus completing the reference positioning. Real-time calculations are performed on the position of each point on the scanning path relative to the optical focal point. depth offset It generates Z-axis micro-motion commands that are strictly time-synchronized with the X and Y axis movements, driving the motion platform to produce displacement in the vertical direction. This allows the patterned surfaces at different depths within the material to sequentially pass through the stationary optical focal point, thus achieving real-time zooming within the layer. Simultaneously, an ultrafast laser is controlled to output pulse trains with specific parameters, utilizing a nonlinear self-focusing effect to form continuous filamentary modified channels within the material. During the switching between adjacent processing layers, software-controlled motion platforms rapidly move the transparent material to the reference depth position of the next layer, achieving seamless splicing of the modified channels through a pre-defined interlayer overlap area.

[0037] In some embodiments of the present invention, The maximum depth coordinate of the current processing layer along the Z-axis is set, i.e., the vertex closest to the material's incident light surface. The laser focus begins to penetrate the material from its shallowest point. As the scanning path deepens, the Z-axis pushes the material upwards, ensuring that the laser focus always follows the pattern and preventing the laser from hitting the material before reaching the focus. In other embodiments of the invention, the pattern is a sphere or a symmetrical structure. Set as the geometric center coordinate of the current process layer in the Z-axis direction to reduce the total travel of the Z-axis.

[0038] If the interlayer overlap is too small, unmodified transparent gaps can easily appear between the layers, leading to visual tomography; if the interlayer overlap is too large, it can cause excessive local energy accumulation, resulting in excessive whitening of the material or even microcracks. In this embodiment of the invention, the Z-direction span of the interlayer overlap region is... to This parameter setting ensures both seamless physical fusion of the interlayer modified channels and maintains overall brightness uniformity. In practical applications, the size of the interlayer overlap area can be adjusted according to the actual effect of the internal engraving.

[0039] Figure 4 This is a schematic diagram illustrating the principle of laser filamentation engraving according to an embodiment of the present invention. The diagram shows two processing layers. The laser beam emitted from the filamentation head is accurately focused onto various points in each processing layer, forming filamentation channels within the transparent material. When the transparent material moves relative to the filamentation head, causing the laser focus to shift from one processing layer to the reference depth coordinate of another, interlayer focusing is achieved. Because each processing layer has undulations in the Z-axis, during processing, it is also necessary to drive the transparent material to move slightly relative to the filamentation head, so that the laser focus follows the pattern within the layer. Only in this way can the three-dimensional shape of each layer's pattern be accurately reproduced.

[0040] In this embodiment of the invention, during the laser engraving process, the spatial position of the filamentation head and its internal optical focus remains relatively static. The transparent material is fixed to a motion platform with X, Y, and Z-axis linkage capabilities. The Z-axis is moved vertically via software control to achieve zooming. This fixed optical path and moving workpiece scheme eliminates the need for expensive and complex 3D dynamic focusing mirrors. A standard three-axis motion platform combined with a high-precision control algorithm can achieve the same or even better dynamic zooming effect, significantly reducing equipment hardware costs. By calculating the depth offset of each point on the path in real time and generating strictly time-synchronized Z-axis micro-motion commands, the influence of mechanical transmission backlash on the focus position is eliminated, ensuring the precision of focus depth control. Maintaining the spatial staticity of the optical focus during material movement avoids optical path jitter or aberrations that may be caused by moving the lens group. Combined with the nonlinear self-focusing effect of ultrafast lasers, this ensures that the generated filamentary modified channel is smooth, continuous, and free of macroscopic defects.

[0041] Traditional internal engraving is a point-to-point or planar layer-by-layer process. When scanning complex curved surfaces, due to the fixed focal depth, it can only form a series of discrete modified points or layered planes, resulting in a noticeable grainy texture or stepped discontinuity on the graphic surface, lacking solidity and smoothness. For graphics with a large Z-axis span, the traditional fixed-focus method leads to severe defocusing at the edges or deeper parts of the graphic, insufficient energy density, and an inability to form clear white filaments, resulting in a bright center and dark sides, or a clear upper layer and a blurred lower layer. This solution's dynamic fine-tuning mechanism ensures that the laser focus is precisely positioned at the target depth within the material at every moment of XY plane scanning. Regardless of the graphic's undulations, it maintains optimal focus throughout, ensuring that the brightness, thickness, and continuity of the filamentary channels are highly consistent from shallow to deep and from flat to steep. Through continuous intralayer focusing, the laser focus is no longer a static plane but can move continuously in real time to follow the three-dimensional undulations of the graphic surface. This makes the generated filamentary modified channels a continuous and smooth curve in space, rather than a broken matrix of points. Combined with interlayer zoom, layer gaps are effectively eliminated, resulting in a 3D visual effect where the engraved graphics appear as if they are floating entities, regardless of the viewing angle. Through software-controlled depth transitions and interlayer overlap, not only are the positions connected when switching between layers, but the overlapping areas also allow the modified channels of the upper and lower layers to be physically merged. This avoids the black or bright lines commonly found in traditional layered processing.

[0042] In some embodiments of the present invention, the ultrafast laser parameters used in step S4 are set as follows: a picosecond or femtosecond laser is used; Burst mode is enabled, and each pulse train contains 2 to 10 sub-pulses; the laser repetition frequency is set to 100kHz to 1000kHz; and the single pulse output energy is 100μJ to 200μJ.

[0043] Figure 5 The laser filament engraving effect image provided in the embodiment of the present invention is relative to... Figure 1 The single-point burst effect image has a more continuous and clearer graphic outline, and a better three-dimensional effect when viewed from multiple angles. In practical applications, an infrared picosecond laser with a wavelength of 1064nm, a repetition frequency of 100kHz, a power of 12.5W, a burst frequency of 3, an output energy of 124μJ, a dot pitch of 10μm, and a velocity of 100mm / s is used.

[0044] like Figure 6 As shown, this embodiment of the invention also provides a transparent material laser engraving system for performing the transparent material laser engraving method described above. The system includes an ultrafast laser processing unit, a multi-axis motion platform, and a data processing and control unit. The ultrafast laser processing unit includes an ultrafast laser and a filamentation head, the filamentation head having a defined effective depth of focus. This is used to excite a nonlinear self-focusing effect within transparent materials to form filamentary modified channels. The multi-axis motion platform has X, Y, and Z-axis linkage capabilities, used to carry and drive the transparent material to be processed in three-dimensional space. The data processing and control unit is electrically connected to the ultrafast laser processing unit and the multi-axis motion platform, and runs laser engraving software on it. The laser engraving software is configured to perform the following operations: Data Analysis: Import the graphic data to be engraved and analyze it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; among which, Defined as the difference between the maximum and minimum depth coordinates in the graphic data; Parameter matching: Obtain the total thickness of the transparent material to be processed. and in accordance with safety constraints Verify or select the filament processing head; wherein, This is the sum of the preset safety thresholds for the upper and lower surfaces; Adaptive hierarchical structure: based on The geometric data distribution characteristics are used to adaptively layer the graphic data to generate a processing sequence containing multiple process processing layers, and a corresponding scanning path is planned for each process processing layer. Dynamic zoom control: For each of the aforementioned process layers, the multi-axis motion platform is controlled to first move the material to the static reference depth position; then, during the XY plane scanning process, the Z axis is driven in real time to make the material follow the three-dimensional undulations of the graphic surface for dynamic fine adjustment, thereby achieving continuous zoom within the layer; and depth transition and interlayer overlap are performed when switching between layers to achieve interlayer zoom.

[0045] When executing the dynamic zoom control, the data processing and control unit is specifically configured to: maintain the spatial position of the filament forming head and its internal optical focal point relatively stationary. For each processing layer, its reference depth coordinates are calculated. The multi-axis motion platform is controlled to move the transparent material along the Z-axis, aligning the target processing area on the material surface with the optical focal point, thus completing the reference positioning. Real-time calculations are performed on the points along the scanning path relative to the optical focal point. depth offset It generates Z-axis micro-motion commands that are strictly time-synchronized with the X and Y axis movements, driving the multi-axis motion platform to produce displacement in the vertical direction. The process involves sequentially passing the stationary optical focal point through patterned surfaces at different depths within the material. The ultrafast laser is controlled to output pulse trains with specific parameters, utilizing a nonlinear self-focusing effect to form continuous filamentary modified channels. During the switching between adjacent processing layers, a multi-axis motion platform is controlled to rapidly move the transparent material to the reference depth position of the next layer, achieving seamless splicing of the modified channels through a preset interlayer overlap area.

[0046] The data processing and control unit is configured to set the Z-axis span of the interlayer overlap region as follows: to .

[0047] When performing the adaptive layering, the data processing and control unit is specifically configured to: based on the effective focal depth of the filament forming head... Set the maximum allowable thickness of a single layer Where k is a preset coefficient, with a value ranging from 0.8 to 1.2. Analyze the geometric data distribution characteristics to identify all valid data segments containing geometric information; for each valid data segment: if its Z-axis span does not exceed... If the valid data segment is directly defined as a single processing layer, then the valid data segment is subdivided into multiple processing layers along the Z-axis, such that the Z-axis span of each processing layer does not exceed [a certain value]. The final list of process layers is then generated.

[0048] The ultrafast laser is a picosecond laser or a femtosecond laser; the ultrafast laser is in Burst mode, and each pulse train contains 2 to 10 sub-pulses; the laser repetition frequency is set to 100 kHz to 1000 kHz; the single pulse output energy is 100 μJ to 200 μJ.

[0049] The above are merely specific embodiments of the present invention and should not be construed as limiting the scope of the present invention. Equivalent variations made by those skilled in the art based on this invention, as well as changes well-known to those skilled in the art, should still fall within the scope of the present invention.

Claims

1. A method for laser engraving on transparent materials, characterized in that, Includes the following steps: Step S1: Import the graphic data to be engraved and parse it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; among which, Defined as the difference between the maximum and minimum depth coordinates in the graphic data; the geometric data distribution characteristics include the connectivity distribution of the graphic data in the Z-axis direction and the Z-axis span of the effective data segment; Step S2: According to A filamentation head with a focal depth matching the total thickness of the transparent material to be processed is selected to ensure that the material surface is not damaged during processing; the effective focal depth of the filamentation head is... ; Step S3: Based on The geometric data distribution characteristics are used to adaptively layer the graphic data to generate a processing sequence containing multiple process processing layers, and a corresponding scanning path is planned for each process processing layer. Step S4: For each of the process layers, firstly control the laser focus to lock the static reference depth; then, during the XY plane scanning process, drive the Z axis in real time to make the laser focus follow the three-dimensional undulations of the graphic surface for dynamic fine adjustment, so as to realize continuous zoom within the layer; during this process, the filamentation effect of ultrafast laser is used to construct a continuous modification channel; and when switching between layers, depth jump and interlayer overlap are performed to realize interlayer zoom.

2. The laser engraving method for transparent materials according to claim 1, characterized in that, Step S4 includes: The transparent material is fixed on a motion platform with X, Y, and Z axis linkage function, keeping the spatial position of the filament processing head and its internal optical focus relatively stationary; For each processing layer, calculate its reference depth coordinates. The motion platform is controlled to move the transparent material along the Z-axis, aligning the target processing area on the material surface with the optical focal point to complete the reference positioning. Real-time calculation of each point on the scan path relative to depth offset It generates Z-axis micro-motion commands that are strictly time-synchronized with the X and Y axis movements, driving the motion platform to produce displacement in the vertical direction. This allows the patterned surfaces at different depths within the material to pass sequentially through the stationary optical focal point, thereby achieving real-time zooming within the layer. Simultaneously, by controlling the output pulse train of an ultrafast laser with specific parameters, a continuous filamentary modified channel is formed inside the material using the nonlinear self-focusing effect. When switching between adjacent processing layers, the software controls the motion platform to quickly move the transparent material to the reference depth position of the next layer, and achieves seamless splicing of the modified channel through the preset interlayer overlap area.

3. The laser engraving method for transparent materials according to claim 2, characterized in that, In step S4, the Z-axis span of the interlayer overlap region is: to .

4. The laser engraving method for transparent materials according to claim 1, characterized in that, The adaptive layering in step S3 includes: Based on the effective depth of the filament processing head Set the maximum allowable thickness of a single layer Where k is a preset coefficient, with a value ranging from 0.8 to 1.2; Analyze the geometric data distribution characteristics to identify all valid data segments containing geometric information; for each valid data segment, if its Z-axis span does not exceed... If the valid data segment is directly defined as a single processing layer, then the valid data segment is subdivided into multiple processing layers along the Z-axis, such that the Z-axis span of each processing layer does not exceed [a certain value]. The final list of process layers is then generated.

5. The laser engraving method for transparent materials according to claim 1, characterized in that, The ultrafast laser parameters used in step S4 are set as follows: Use picosecond or femtosecond lasers; Enable Burst mode, where each pulse train contains 2 to 10 sub-pulses; The laser repetition frequency is set to 100kHz to 1000kHz; The single-pulse output energy is 100μJ to 200μJ.

6. The laser engraving method for transparent materials according to claim 1, characterized in that, In step S2, the effective focal depth of the filament forming head Meet safety constraints: ;in, This is the sum of the preset safety thresholds for the upper and lower surfaces; This represents the total thickness of the transparent material to be processed.

7. A transparent material laser engraving system for performing the transparent material laser engraving method as described in any one of claims 1 to 6, characterized in that, include: Ultrafast laser processing unit: includes an ultrafast laser and a filamentation head, the filamentation head having a defined effective depth of focus. It is used to excite a nonlinear self-focusing effect inside transparent materials to form filament-modified channels; Multi-axis motion platform: It has X, Y and Z three-axis linkage function and is used to carry and drive the transparent material to be processed to move in three-dimensional space; Data processing and control unit: electrically connected to the ultrafast laser processing unit and multi-axis motion platform, running laser engraving software configured to perform the following operations: Data Analysis: Import the graphic data to be engraved and analyze it to obtain the overall Z-axis span of the graphic. And the geometric data distribution characteristics along the Z-axis; among which, Defined as the difference between the maximum and minimum depth coordinates in the graphic data; Parameter matching: Obtain the total thickness of the transparent material to be processed. and in accordance with safety constraints Verify or select the filament processing head; wherein, This is the sum of the preset safety thresholds for the upper and lower surfaces; Adaptive hierarchical structure: based on The geometric data distribution characteristics are used to adaptively layer the graphic data to generate a processing sequence containing multiple process processing layers, and a corresponding scanning path is planned for each process processing layer. Dynamic zoom control: For each of the aforementioned process layers, the multi-axis motion platform is controlled to first move the material to the static reference depth position; then, during the XY plane scanning process, the Z axis is driven in real time to make the material follow the three-dimensional undulations of the graphic surface for dynamic fine adjustment, thereby achieving continuous zoom within the layer; and depth transition and interlayer overlap are performed when switching between layers to achieve interlayer zoom.

8. The transparent material laser engraving system according to claim 7, characterized in that, When executing the dynamic zoom control, the data processing and control unit is specifically configured as follows: The spatial position of the filament forming head and its internal optical focal point remains relatively stationary; For each processing layer, calculate its reference depth coordinates. The multi-axis motion platform is controlled to move the transparent material in the Z-axis direction, so that the target processing area on the material surface is aligned with the optical focal point, thus completing the reference positioning; Real-time calculation of each point on the scan path relative to depth offset It generates Z-axis micro-motion commands that are strictly time-synchronized with the X and Y axis movements, driving the multi-axis motion platform to produce displacement in the vertical direction. This allows the patterned surfaces at different depths within the material to pass sequentially through the stationary optical focal point; The ultrafast laser is controlled to output pulse trains with specific parameters to form a continuous filamentary modified channel by utilizing the nonlinear self-focusing effect; When switching between adjacent processing layers, the multi-axis motion platform is controlled to quickly move the transparent material to the reference depth position of the next layer, and the modified channel is seamlessly spliced ​​through the preset interlayer overlap area.

9. The transparent material laser engraving system according to claim 8, characterized in that, The data processing and control unit is configured to set the Z-axis span of the interlayer overlap region as follows: to .

10. The transparent material laser engraving system according to claim 7, characterized in that, When executing the adaptive hierarchical structure, the data processing and control unit is specifically configured as follows: Based on the effective depth of the filament processing head Set the maximum allowable thickness of a single layer Where k is a preset coefficient, with a value ranging from 0.8 to 1.2; Analyze the geometric data distribution characteristics to identify all valid data segments containing geometric information; For each valid data segment: if its Z-axis span does not exceed If the valid data segment is directly defined as a single processing layer, then the valid data segment is subdivided into multiple processing layers along the Z-axis, such that the Z-axis span of each processing layer does not exceed [a certain value]. ; The final list of process layers is then generated.

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