Three-dimensional laser writing method, device, computer equipment and system

Abstract

The application relates to a three-dimensional laser engraving method, device, computer equipment and system. The method comprises the following steps: sequentially acquiring a two-dimensional gray scale image corresponding to each layer of an engraving object; acquiring engraving image data of each engraving point based on the two-dimensional gray scale image; sequentially controlling a displacement table to move to a starting position corresponding to each row of the engraving points and controlling the displacement table to move according to a specified program; and when the displacement table reaches a specified position, controlling a digital micromirror to perform parallel laser engraving operation based on the engraving image data of the corresponding engraving point. Through the application, the technical problems of low engraving efficiency and poor engraving quality in the related art are solved. The splicing step is removed by moving the displacement table, and the digital micromirror performs parallel laser engraving, thereby improving the efficiency and quality of laser engraving.

Description

Technical Field

[0001] This application relates to the field of 3D lithography technology, and in particular to a three-dimensional laser writing method, apparatus, computer equipment and system. Background Technology

[0002] With the development of photolithography technology, 3D laser writing, such as laser writing based on two-photon polymerization, double absorption effect, and edge light suppression effect, can achieve the processing of nanometer- to centimeter-scale 3D structural objects while maintaining high precision at the nanometer to micrometer level. As photolithography technology allows the realization of micrometer- or even nanometer-scale functional features on complex, large-sized objects, it is particularly important in the research of high-precision novel complex devices and structures, such as on-chip integrated systems, micro-nano optics, and metamaterials.

[0003] In related technologies, 3D laser engraving lithography generally employs scanning methods that directly control the movement of the laser beam, such as galvanometer scanning. When the size and structure of the object being engraved are large, these technologies often suffer from insufficient field of view, requiring multi-directional scanning and stitching. Furthermore, the use of single-beam engraving in these technologies further increases the cost of the engraving process. Therefore, these technologies result in low engraving efficiency and poor engraving quality.

[0004] There is currently no effective solution to the technical problems of low writing efficiency and poor writing quality in related technologies. Summary of the Invention

[0005] Based on this, this application provides a three-dimensional laser engraving method, apparatus, computer equipment, and system to solve the technical problems of low engraving efficiency and poor engraving quality in related technologies.

[0006] In a first aspect, this application provides a three-dimensional laser engraving method, the method comprising:

[0007] Sequentially obtain the two-dimensional grayscale image corresponding to each layer of the inscribed object;

[0008] Based on the two-dimensional grayscale image, obtain the inscription image data for each inscription point;

[0009] The displacement stage is sequentially controlled to move to the starting position corresponding to each row of writing points and the displacement stage is controlled to move according to a specified program. When the displacement stage reaches the specified position, the digital micromirror is controlled to perform parallel laser writing operation based on the writing image data of the corresponding writing point.

[0010] In one embodiment, after obtaining the two-dimensional grayscale image corresponding to each layer of the inscribed object, the method further includes:

[0011] The two-dimensional grayscale image is interpolated to obtain a pixelated grayscale image, the resolution of which is determined based on the writing length and pixel size.

[0012] In one embodiment, after sequentially acquiring the two-dimensional grayscale image corresponding to each layer of the inscribed object, the method further includes:

[0013] If the pixel value of the two-dimensional grayscale image is 0, then the pixel value of the two-dimensional grayscale image is inverted to obtain an inverted grayscale image.

[0014] Based on the slice layer number corresponding to the two-dimensional grayscale image and the total number of slice layers, the pixel values ​​of the inverted grayscale image are adjusted to obtain grayscale writing data.

[0015] In one embodiment, obtaining the inscription image data for each inscription point based on the two-dimensional grayscale image includes:

[0016] The grayscale writing data corresponding to the two-dimensional grayscale image is split to obtain multiple writing point writing data;

[0017] Based on the parameters of the digital micromirror, the writing data of each writing point is converted to obtain the writing image data.

[0018] In one embodiment, the process of obtaining the writing data of the multiple writing points includes:

[0019] Extract each column of the grayscale writing data to obtain multiple columns of writing data;

[0020] The number of interleaving points in the column direction is calculated based on the number of writing points in the column direction, the pixel size, and the spacing between adjacent light rays in the column direction at the focal plane of the objective lens.

[0021] Based on the number of column direction interleavings, the column direction zero-padding operation is performed sequentially on the column writing point writing data in each column writing data;

[0022] Perform a size normalization operation on the zero-padded column write points;

[0023] Extract each row of the grayscale writing data after the normalization operation to obtain multiple rows of writing data;

[0024] The number of interleavings in the row direction is calculated based on the number of writing points in the row direction, the pixel size, and the spacing between adjacent light rays in the row direction at the focal plane of the object distance.

[0025] Based on the number of row direction interleavings, row direction zero padding is performed sequentially on the row writing point writing data in each row writing data;

[0026] The size of the zero-padded line writing data is normalized to obtain the writing data of the writing points.

[0027] In one embodiment, the parameters of the digital micromirror include at least: the number of effective projection units and the total number of projection units.

[0028] In one embodiment, controlling the displacement stage to move according to a specified program includes:

[0029] If the current row is an even number of rows, the inscribed image data is sorted in ascending order based on the column number of the inscription point, and the displacement stage is controlled to move in the first direction.

[0030] If the current row is an odd number of rows, the inscribed image data is sorted in descending order based on the column number of the inscription point, and the displacement stage is controlled to move in a second direction, the first direction being opposite to the second direction.

[0031] Secondly, this application also provides a three-dimensional laser engraving apparatus. The apparatus includes:

[0032] The first acquisition module is used to sequentially acquire the two-dimensional grayscale image corresponding to each layer of the inscribed object;

[0033] The second acquisition module is used to acquire the inscription image data of each inscription point based on the two-dimensional grayscale image;

[0034] The writing module is used to sequentially control the displacement stage to move to the starting position corresponding to each row of writing points and control the displacement stage to move according to a specified program. When the displacement stage reaches the specified position, it controls the digital micromirror to perform parallel laser writing operation based on the writing image data of the corresponding writing point.

[0035] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to perform the following steps:

[0036] Sequentially obtain the two-dimensional grayscale image corresponding to each layer of the inscribed object;

[0037] Based on the two-dimensional grayscale image, obtain the inscription image data for each inscription point;

[0038] The displacement stage is sequentially controlled to move to the starting position corresponding to each row of writing points and the displacement stage is controlled to move according to a specified program. When the displacement stage reaches the specified position, the digital micromirror is controlled to perform parallel laser writing operation based on the writing image data of the corresponding writing point.

[0039] Fourthly, this application also provides a three-dimensional laser engraving system, the system comprising:

[0040] A writing laser is used to emit writing laser light;

[0041] A beam expander is used to expand the laser beam used for writing.

[0042] Digital micromirrors are used to write light beams in parallel and adjust the light intensity by the number of micromirrors that are turned on.

[0043] Microlens arrays are used to generate parallel writing points;

[0044] A lens system is used to focus the parallel writing beams onto the photolithographic sample;

[0045] Translational motion mechanism, used to achieve horizontal and vertical movement of the sample;

[0046] A computer for implementing the steps of the method described in any one of the first aspects above.

[0047] This application provides a three-dimensional laser writing method, apparatus, computer equipment, and system. The method includes: sequentially acquiring a two-dimensional grayscale image corresponding to each layer of the writing object; acquiring writing image data for each writing point based on the two-dimensional grayscale image; sequentially controlling a displacement stage to move to the starting position corresponding to each row of writing points and controlling the displacement stage to move according to a specified program; when the displacement stage reaches the specified position, controlling a digital micromirror to perform parallel laser writing operations based on the writing image data of the corresponding writing point. During the writing process, all writing points remain stationary, and multi-directional scanning is only required by moving the displacement stage. Compared with the method of directly controlling the beam movement for scanning in related technologies, this avoids the need for stitching when scanning large-size structures due to insufficient field of view, thus achieving stitch-free writing during the scanning process. Simultaneously, multiple laser beams required for parallel writing are generated by the digital micromirror, thereby performing laser writing in parallel. Therefore, this application solves the technical problems of low writing efficiency and poor writing quality in related technologies. By eliminating the splicing step through a moving displacement stage and performing laser writing in parallel through digital micromirrors, the efficiency and quality of laser writing are improved. Attached Figure Description

[0048] Figure 1 This is an application environment diagram of a three-dimensional laser engraving method according to an embodiment of this application;

[0049] Figure 2 This is a schematic flowchart of a three-dimensional laser engraving method according to an embodiment of this application;

[0050] Figure 3 A flowchart illustrating a grayscale writing data generation method according to an embodiment of this application;

[0051] Figure 4This is a flowchart illustrating a method for generating writing data at writing points according to an embodiment of this application;

[0052] Figure 5 This is a schematic flowchart of a method for generating inscribed image data according to an embodiment of this application;

[0053] Figure 6 This is a schematic diagram of the writing path according to an embodiment of this application;

[0054] Figure 7 This is a flowchart illustrating a three-dimensional laser engraving method according to another embodiment of this application;

[0055] Figure 8 This is a structural block diagram of a three-dimensional laser engraving apparatus according to an embodiment of this application;

[0056] Figure 9 This is an internal structural diagram of a computer device according to an embodiment of this application;

[0057] Figure 10 This is a schematic diagram of the structure of a three-dimensional laser engraving system according to an embodiment of this application. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0059] The three-dimensional laser engraving method provided in this application embodiment can be applied to, for example... Figure 1 In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be integrated onto server 104 or located in the cloud or on other network servers. Terminal 102 can be, but is not limited to, various personal computers, laptops, smartphones, tablets, IoT devices, and portable wearable devices. IoT devices can include smart speakers, smart TVs, smart air conditioners, smart in-vehicle devices, etc. Portable wearable devices can include smartwatches, smart bracelets, head-mounted devices, etc. Server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0060] Please see Figure 2 , Figure 2 This is a flowchart illustrating a three-dimensional laser engraving method according to an embodiment of this application.

[0061] In one embodiment, such as Figure 2 As shown, a three-dimensional laser engraving method is provided, including:

[0062] S202: Sequentially obtain the two-dimensional grayscale image corresponding to each layer of the inscribed object.

[0063] Specifically, the computer reads the model data of the object to be inscribed, obtaining a two-dimensional grayscale image corresponding to each slice layer. It can be understood that each two-dimensional grayscale image corresponds to a slice layer of the model data; the thinner the slice layer, the lower the step effect in the inscription result, and the higher the inscription quality. By traversing the two-dimensional grayscale images corresponding to each slice layer and executing the three-dimensional laser inscription method in this embodiment, the overall inscription task is completed.

[0064] S204: Obtain the inscription image data for each inscription point based on the two-dimensional grayscale image.

[0065] Specifically, the two-dimensional grayscale image is processed to obtain the inscription pattern data for each inscription point. In this embodiment, an inscription point refers to an execution point during the inscription process, and the inscription pattern data contains all the pixel data of the inscription area corresponding to that execution point.

[0066] S206: Sequentially control the displacement stage to move to the starting position corresponding to each row of writing points and control the displacement stage to move according to the specified program. When the displacement stage reaches the specified position, control the digital micromirror to perform parallel laser writing operation based on the writing image data of the corresponding writing points.

[0067] Specifically, after acquiring the writing image data corresponding to each writing point, all writing image data corresponding to each row of writing points are read sequentially. The displacement stage is moved to the starting position corresponding to that row of writing points, and the displacement stage is controlled to move according to a specified program. When the displacement stage moves to a specified position (corresponding to a writing point, i.e., the execution point), the digital micromirror device (DMD) is controlled to perform laser writing operations in parallel based on the corresponding writing image data.

[0068] In this embodiment, the displacement stage is used to support the photolithography sample. The digital micromirror in this embodiment includes a normally closed region and a modulation region. All micromirrors in the normally closed region are in a normally closed state, and reflected light cannot enter the photolithography sample through the micromirrors in the normally closed region. The modulation region is set with multi-faceted micromirrors in a two-dimensional array, which can realize the modulation of the intensity of multi-level reflected light and parallel laser writing.

[0069] Understandably, this embodiment uses a digital micromirror to generate and control the multiple beams required for parallel writing, while a displacement stage is used to achieve multi-axis scanning. During the writing process, the writing point array remains stationary, and the device achieves parallel writing solely through the movement of the displacement stage. Compared to related technologies that directly control beam scanning, such as galvanometer scanning, moving the displacement stage for scanning can solve the problem of large-size structures needing to be stitched together due to insufficient field of view, achieving completely seamless writing.

[0070] Understandably, this embodiment uses a two-dimensional dot matrix inscription algorithm, which can improve the inscription speed by more than 100 times compared to single-beam inscription. In addition, this embodiment replaces traditional layer-cut data with grayscale layer-cut data, effectively solving the step problem between layers, and realizing the combination of parallel inscription based on digital micromirror and 3D grayscale inscription, achieving the dual effect of speed improvement and quality optimization.

[0071] In this embodiment, all writing points remain stationary during the writing process. Multi-directional scanning is achieved solely through a moving stage. Compared to related technologies that directly control the beam movement for scanning, this avoids the need for stitching when scanning large structures due to insufficient field of view, thus achieving stitch-free writing during the scanning process. Simultaneously, multiple laser beams are generated for parallel writing using a digital micromirror, enabling parallel laser writing. Therefore, this application solves the technical problems of low writing efficiency and poor writing quality in related technologies. By eliminating the stitching step through a moving stage and performing parallel laser writing through a digital micromirror, the efficiency and quality of laser writing are improved.

[0072] In another embodiment, after obtaining the two-dimensional grayscale image corresponding to each layer of the inscribed object, the method further includes:

[0073] Interpolation is performed on the two-dimensional grayscale image to obtain a pixelated grayscale image. The resolution of the pixelated grayscale image is determined based on the writing length and pixel size.

[0074] Specifically, the two-dimensional grayscale images of each layer are read sequentially, and interpolation processing is performed on the two-dimensional grayscale images to improve their resolution, thereby obtaining a pixelated grayscale image. The resolution of this pixelated grayscale image is determined based on the actual inscription length and the pixel size of the pixels in the image.

[0075] For example, a two-dimensional grayscale image is read; the grayscale image is then interpolated in two dimensions. Interpolation methods include, but are not limited to, bilinear interpolation, quadratic interpolation, cubic spline interpolation, or custom function interpolation. After repixelation, the number of pixels in the x and y directions are npixelx = lx / pixelsize and npixelly = ly / pixelsize, respectively, where lx and ly represent the actual writing lengths in the x and y directions of the two-dimensional grayscale image, and pixelsize represents the set pixel size.

[0076] In this embodiment, a pixelated grayscale image is obtained by interpolating the two-dimensional grayscale image to ensure that the pixelated grayscale image can meet the size requirements in the actual engraving process, thereby improving the engraving accuracy.

[0077] In another embodiment, after sequentially obtaining the two-dimensional grayscale image corresponding to each layer of the inscribed object, the method further includes:

[0078] Step 1: If the pixel value of the 2D grayscale image is 0, then invert the pixel value of the 2D grayscale image to obtain the inverted grayscale image.

[0079] Step 2: Based on the slice layer number corresponding to the two-dimensional grayscale image and the total number of slice layers, adjust the pixel values ​​of the inverted grayscale image to obtain grayscale writing data.

[0080] Specifically, in this embodiment, the grayscale value of the top layer is set to 0. If the pixel value of the current 2D grayscale image is 0, it indicates that the current layer is the top layer. At this time, the pixel values ​​of the 2D grayscale image are inverted to obtain an inverted grayscale image. The inversion operation means assigning the difference between the maximum grayscale value and the current pixel's grayscale value to the current pixel. After obtaining the inverted grayscale image, the pixel values ​​of the inverted grayscale image are adjusted based on the position information of the corresponding slice layer, i.e., the slice layer number and the total number of slice layers, to obtain the grayscale writing data.

[0081] Please see Figure 3 , Figure 3 A schematic flowchart of a grayscale writing data generation method according to an embodiment of this application.

[0082] For example, such as Figure 3 As shown, the process first involves interpolating the 2D grayscale image to obtain a pixelated grayscale image. Then, the pixelated grayscale image is inverted to obtain an inverted grayscale image. Finally, the grayscale data is obtained from the inverted grayscale image. Specifically, the steps include:

[0083] a) Read the two-dimensional grayscale image;

[0084] b) Perform two-dimensional interpolation on the grayscale image. The interpolation method can be bilinear interpolation, quadratic interpolation, cubic spline interpolation, or a custom function interpolation. After repixelation, the number of pixels in the x and y directions are npixelx = lx / pixelsize and npixelly = ly / pixelsize, respectively, where lx and ly represent the actual writing length in the x and y directions of the grayscale image, and pixelsize represents the set pixel size.

[0085] c) Read the re-pixelated grayscale two-dimensional data, denoted as imagegray(x, y); initialize i = 0;

[0086] d) Adjust the bottom layer to a grayscale value of 0. If the grayscale value is 0, it means the bottom layer is grayscale. imagegray(x, y) = maxgray - imagegray(x, y), where maxgray represents the maximum grayscale value.

[0087] e) Set the total height of the inscribed structure to h and the layer cutting thickness to dz, and obtain the two-dimensional data of the grayscale value of the i-th layer: layergray(x, y, i) = (imagegray(x, y) - i / nz * maxgray) * nz, where nz = h / dz represents the layer number;

[0088] f) Reset the data type and bit depth of layergray(x, y, i) to maintain the same level as the two-dimensional grayscale in step a. Figure 1 To;

[0089] g) Set i = i + 1 and repeat step ef to obtain grayscale data for all layers, totaling nz sets of 3D grayscale data, which is in the form of a three-dimensional array layergray(x, y, i).

[0090] In this embodiment, the two-dimensional grayscale image is first inverted, and then the pixel values ​​are adjusted based on the slice layer number and the total number of slice layers, so as to ensure that the obtained grayscale writing data matches the corresponding slice layer, thereby improving the writing accuracy.

[0091] In another embodiment, obtaining the inscription image data for each inscription point based on a two-dimensional grayscale image includes:

[0092] Step 1: Decompose the grayscale data corresponding to the two-dimensional grayscale image to obtain multiple writing point writing data;

[0093] Step 2: Based on the parameters of the digital micromirror, the writing data of each writing point is converted to obtain the writing image data.

[0094] Specifically, after obtaining the two-dimensional grayscale image corresponding to each slice layer, the two-dimensional grayscale image is processed to obtain grayscale inscription data; the grayscale inscription data is split based on different inscription points to obtain inscription point inscription data corresponding to each inscription point; the inscription point inscription data of each inscription point is converted by the parameters of the digital microscope to obtain the inscription image data corresponding to each inscription point.

[0095] In this embodiment, the grayscale writing data is first split into writing data corresponding to multiple writing points, and then the writing image data is obtained by adjusting the parameters of the digital micromirror. This ensures that the digital micromirror can directly read the writing image data and perform the writing operation during the writing process, thereby improving the efficiency of three-dimensional laser writing.

[0096] In another embodiment, the process of obtaining writing data at multiple writing points includes:

[0097] Step 1: Extract data from each column of the grayscale data to obtain multiple columns of data.

[0098] Step 2: Calculate the number of interleavings in the column direction based on the number of writing points in the column direction, the pixel size, and the spacing between adjacent light rays in the column direction at the focal plane of the objective lens;

[0099] Step 3: Based on the number of column direction interleavings, perform column direction zero padding on the column write points of each column of data in turn;

[0100] Step 4: Perform size normalization on the zero-padded column write points;

[0101] Step 5: Extract each row of the grayscale writing data after the normalization operation to obtain multiple rows of writing data;

[0102] Step 6: Calculate the number of interlacing points in the row direction based on the number of writing points, pixel size, and the distance between adjacent light rays in the row direction at the focal plane.

[0103] Step 7: Based on the number of row direction interleavings, perform row direction zero padding on the row writing points of each row of writing data in turn;

[0104] Step 8: Perform size normalization on the zero-padded row write data to obtain the write data.

[0105] In this embodiment, when performing size normalization on column or row write point data, the largest group among the column or row write points can be used for size unification.

[0106] Specifically, during parallel writing, the writing data for different channels are not output simultaneously, and there is a certain delay between different channels. Therefore, it is necessary to perform zero-padding on the writing data of each channel in sequence. In the zero-padding process, the number of interleaving points in the column direction is first determined by the number of writing points in the column direction, the pixel size, and the spacing between adjacent light rays at the focal plane of the objective lens. Then, zero-padding is performed on the row writing data based on the number of interleaving points.

[0107] Please see Figure 4 , Figure 4 This is a flowchart illustrating a method for generating writing data at writing points according to an embodiment of this application.

[0108] For example, such as Figure 4 As shown, the process of generating writing data for writing points includes:

[0109] a) Read the writing data of the current layer, denoted as layergray(x, y); initialize xi = 0;

[0110] b) Read the data in column xi: layergray(xi, y);

[0111] c) Extract the elements in layergray(xi, y). Output layerpoints1(xi, y) as the first row of inscription points, elements 0, nbeamsy, 2nbeamsy, ... as the second row of inscription points, and so on, until n-1, 2nbeamsy-1, 3nbeamsy-1, ... are output as the last row of inscription points, where nbeamsy is the number of inscription points in the y direction in parallel.

[0112] d) Repeat step bc for different xi to obtain the writing data for each writing point: layerpoints1(x, y), layerpoints2(x, y), ..., layerpointsnbeamsy(x, y);

[0113] e) Since the delay is proportional to the number of crossovers ncrossy, the number of crossovers ncrossy in the y direction is calculated according to the formula (ncrossy×nbeamsy+1)×pixelsize=dbeams, where nbeamsy is the number of y-direction writing points used in parallel writing, pixelsize is the pixel size, and dbeams is the distance between the two adjacent beams of light used in parallel writing at the focal plane of the objective lens.

[0114] f) Pad the two-dimensional writing data obtained in step d with zeros. The first row of writing points is not padded with zeros. The second row of writing points is padded with zeros from the ncrossy row at the beginning position, and so on. The last row of writing points is padded with zeros from the (nbeamsy-1)*ncrossy row at the beginning position.

[0115] g) Unify the size of the data written at each line of writing points, take the group with the largest data volume as the standard, and add a sufficient number of zeros at the end of the other groups;

[0116] h) Read the first row of zero-padding data for each row of writing points: layerpoints1(x, yi), layerpoints2(x, yi), ..., layerpointsnbeamsy(x, yi);

[0117] i) Extract data from the first row of each row, and output layerpoint11(x, yi), layerpoint21(x, yi), ... as the first write point of each row; output layerpoint12(x, yi), layerpoint22(x, yi), ... as the second write point of each row; and so on, output layerpoint1nbeamsx(x, yi), layerpoint2nbeamsx(x, yi), ... as the last write point of each row;

[0118] j) Calculate the number of crossovers in the x-direction ncrossx according to the formula (ncrossx×nbeamsx+1)×pixelsize=dbeams, where nbeamsx is the number of x-direction writing points used for parallel writing;

[0119] k) Perform zero-padding operation. The first column inscription points layerpoint11(x, yi), layerpoint21(x, yi), ... are not padded with zeros. The second column inscription points layerpoint12(x, yi), layerpoint22(x, yi), ... are padded with zeros of column ncrossx at the beginning position, and so on. The last column inscription point is padded with zeros of column (nbeamsx-1)*ncrossx at the beginning position.

[0120] l) Unify the size of the data written in each group, take the group with the largest data volume as the standard, and add enough zeros to the end of the other groups;

[0121] m) Integrate the 3D grayscale writing data of each writing point into a four-dimensional array imagepoints(pi, pj, x, y) = layerpointpipj(x, y), where pi = 1, 2, ..., nbeamsx; pj = 1, 2, ..., nbeamsy.

[0122] In this embodiment, the number of interleavings in the column direction is determined based on the number of writing points, pixel size, and the spacing between adjacent light rays at the focal plane of the objective lens. The number of interleavings is used to pad the row writing data with zeros, which ensures the matching between different row writing data, solves the inter-channel delay problem in the parallel writing process, and thus improves the accuracy of 3D laser writing.

[0123] In another embodiment, the parameters of the digital micromirror include at least the number of effective projection units and the total number of projection units.

[0124] Specifically, in this embodiment, the writing data of each writing point is converted by the effective projection unit number and the total projection unit number of the digital micromirror to obtain the writing image data.

[0125] Please see Figure 5 , Figure 5 This is a schematic flowchart of a method for generating image data for inscription according to an embodiment of this application.

[0126] For example, such as Figure 5 As shown, the specific steps for generating the inscribed image data include:

[0127] a) Read the 3D grayscale inscription data of each inscription point after splitting: imagepoints(); initialize xi = 0; yi = 0;

[0128] b) Create a two-dimensional array imageDMD(), with 0 elements and an array size equal to the number of pixels of the digital micromirrors used; initialize i = 0; j = 0;

[0129] c) Create a one-dimensional data pointson1D(), with an array element of 1 and an array size equal to the grayscale values ​​of imagepoints(i, j, xi, yi);

[0130] d) Convert the one-dimensional array pointson1D() into a two-dimensional array pointson2D(), with neff as the number of columns and 0 as any extra elements, where neff represents the number of digital micromirror effective projection units used by a microlens;

[0131] e) Replace the elements of imageDMD() with pointsson2D() from index positions (nall-neff) / 2+i*nall, (nall-neff) / 2+j*nall, where nall represents the total number of digital micromirror projection units used by a microlens;

[0132] f)i = i + 1; repeat step ce until all x-direction inscription points have been traversed;

[0133] g)j = j + 1; Repeat step cf until all inscription points have been traversed;

[0134] h) Get imageDMD(), which represents the image data loaded by the digital micromirror at the current xi, yi coordinates;

[0135] i) xi = xi + 1; Repeat step bh until all column data has been traversed;

[0136] j)yi = yi + 1; Repeat step bi until all data has been traversed;

[0137] k) yields a four-dimensional array imageDMD4D(datax, datay, x, y), which can be viewed as a special two-dimensional array, where each array element is a two-dimensional grayscale image.

[0138] In another embodiment, controlling the displacement stage to move according to a specified program includes:

[0139] If the current row is an even number of rows, the inscribed image data is sorted in ascending order based on the column number of the inscription point, and the displacement stage is controlled to move in the first direction.

[0140] If the current row is an odd number of rows, the inscribed image data is sorted in descending order based on the column number of the inscription point, and the displacement stage is controlled to move in the second direction, which is the opposite of the first direction.

[0141] Specifically, it determines whether the current row is an odd or even row. If the current row is an even row, the inscribed image data is sorted in ascending order based on the column number of the inscription point, and the displacement stage is controlled to move in the first direction. If the current row is an odd row, the inscribed image data is sorted in descending order based on the column number of the inscription point, and the displacement stage is controlled to move in the second direction.

[0142] In this embodiment, the end position of the previous row is the start position of the next row, and the first direction is opposite to the second direction.

[0143] Please see Figure 6 , Figure 6 This is a schematic diagram of the writing path according to an embodiment of this application.

[0144] For example, such as Figure 6 As shown, the specific steps for controlling the displacement stage to move according to the specified program include:

[0145] a) When the displacement stage moves to the starting position, if the current row number j is even, the starting position (position A in the figure) is in the x-direction of the initial position (position C in the figure), and the initial position is the first element of the row; otherwise, the starting position (position G in the figure) is in the x-direction of the initial position (position E in the figure), and the initial position is the last element of the row.

[0146] b) The displacement stage accelerates along the x-direction or -x-direction, and enters the uniform motion state (stage D in the figure) through the acceleration uniform transition zone (stage B / stage F in the figure);

[0147] c) The displacement stage generates a trigger signal when it passes through the designated position, that is, the starting position of each column (position C / position E in the figure);

[0148] d) The displacement stage moves to the end of the writing process (position E / position C in the diagram) and begins to decelerate;

[0149] e) The displacement stage comes to a complete stop after passing through the uniform speed interval transition zone (stage F / stage B in the figure).

[0150] In this embodiment, an S-shaped inscription path is formed by the above method, and the sorting of the inscription image data of the inscription points is adaptively adjusted, thereby reducing the movement path of the displacement stage during the inscription process and thus improving the inscription efficiency.

[0151] Please see Figure 7 , Figure 7 This is a flowchart illustrating a three-dimensional laser engraving method according to another embodiment of this application.

[0152] For example, such as Figure 7 As shown, this application also discloses specific steps of a three-dimensional laser inscription method, including:

[0153] a) Turn on the writing laser to generate a writing laser beam; initialize i = 0;

[0154] b) The displacement stage moves along the xyz axis to the starting position of the i-th layer. Using the starting position (x0, y0, z0) of the first layer as a reference position, the pattern will be stitched together layer by layer, that is, after each layer is finished, it moves along the z direction once, and the x and y coordinates are restored to x0 and y0;

[0155] c) Decompose the writing data of the i-th layer to obtain the writing data of each writing point;

[0156] d) Convert the inscription data of each inscription point into digital micromirror inscription image data; initialize j = 0;

[0157] e) Move the displacement stage along the xy axis to the starting position of the j*nbeamsy row of the i-th layer, where nbeamsy is the number of parallel writing points in the y-direction used for writing;

[0158] f) Read all the inscribed patterns in the j-th row of the digital microscope, and determine whether j is even. If it is, arrange all the inscribed patterns in the j-th row of the digital microscope in ascending order of column number; if it is not, arrange all the inscribed patterns in the j-th row of the digital microscope in descending order of column number.

[0159] g) Write the pattern sequence of the j-th row of the digital micromirror into the digital micromirror buffer, start the digital micromirror, and the digital micromirror is in a waiting-to-trigger state;

[0160] h) Start the displacement stage. The displacement stage moves according to the specified program and generates a trigger signal at the specified position. The digital micromirror is then triggered and outputs the pattern sequence in sequence to complete the writing of the j*n beamsy line of the i-th group. The specified program is related to the parity of j.

[0161] i) Set j = j + 1 and repeat step eh until all rows of the i-th layer are written;

[0162] j) Set i = i + 1 and repeat step bi until all groups are written.

[0163] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0164] Based on the same inventive concept, this application also provides a three-dimensional laser engraving apparatus for implementing the three-dimensional laser engraving method described above. The solution provided by this apparatus is similar to the implementation described in the above method; therefore, the specific limitations in one or more embodiments of the three-dimensional laser engraving apparatus provided below can be found in the limitations of the three-dimensional laser engraving method described above, and will not be repeated here.

[0165] In one embodiment, such as Figure 8 As shown, a three-dimensional laser engraving device is provided, comprising:

[0166] The first acquisition module 10 is used to sequentially acquire the two-dimensional grayscale image corresponding to each layer of the inscribed object;

[0167] The second acquisition module 20 is used to acquire the inscription image data of each inscription point based on the two-dimensional grayscale image;

[0168] The writing module 30 is used to sequentially control the displacement stage to move to the starting position corresponding to each row of writing points and control the displacement stage to move according to the specified program. When the displacement stage reaches the specified position, it controls the digital micromirror to perform parallel laser writing operation based on the writing image data of the corresponding writing points.

[0169] The writing module 30 is also used to sort the writing image data in ascending order based on the column number of the writing point if the current row is an even row, and control the displacement stage to move based on the first direction;

[0170] If the current row is an odd number of rows, the inscribed image data is sorted in descending order based on the column number of the inscription point, and the displacement stage is controlled to move in the second direction, which is opposite to the first direction.

[0171] The three-dimensional laser engraving device also includes an interpolation module;

[0172] The interpolation module is used to interpolate a two-dimensional grayscale image to obtain a pixelated grayscale image. The resolution of the pixelated grayscale image is determined based on the writing length and pixel size.

[0173] The three-dimensional laser engraving device also includes a grayscale engraving data acquisition module;

[0174] The grayscale data acquisition module is used to invert the pixel values ​​of the two-dimensional grayscale image if the pixel value of the two-dimensional grayscale image is 0, so as to obtain an inverted grayscale image.

[0175] Based on the slice layer number corresponding to the two-dimensional grayscale image and the total number of slice layers, the pixel values ​​of the inverted grayscale image are adjusted to obtain grayscale characterization data.

[0176] The grayscale inscription data acquisition module is also used to split the grayscale inscription data corresponding to the two-dimensional grayscale image to obtain multiple inscription point inscription data.

[0177] Based on the parameters of the digital micromirror, the writing data of each writing point is transformed to obtain the writing image data;

[0178] The grayscale writing data acquisition module is also used to extract each column of grayscale writing data to obtain multiple columns of writing data;

[0179] The number of interleaving points in the column direction is calculated based on the number of writing points in the column direction, the pixel size, and the spacing between adjacent light rays in the column direction at the focal plane of the objective lens.

[0180] Based on the number of column direction interleavings, the column direction zero-padding operation is performed on the column writing points in each column writing data in turn;

[0181] Perform a size normalization operation on the zero-padded column write points;

[0182] Extract each row of the grayscale writing data after the normalization operation to obtain multiple rows of writing data;

[0183] The number of interleavings in the row direction is calculated based on the number of writing points in the row direction, the pixel size, and the spacing between adjacent light rays in the row direction at the focal plane of the object distance.

[0184] Based on the number of row direction interleaving, row direction zero padding is performed on the row writing point writing data in each row writing data in turn;

[0185] The size of the zero-padded row write data is normalized to obtain the write data of the write points.

[0186] Each module in the aforementioned three-dimensional laser engraving device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in the processor of a computer device in hardware form or independent of it, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0187] In one embodiment, a computer device is provided, which may be a terminal, and its internal structure diagram may be as follows: Figure 9 As shown, the computer device includes a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, mobile cellular networks, NFC (Near Field Communication), or other technologies. When the computer program is executed by the processor, it implements a three-dimensional laser engraving method. The display screen can be an LCD screen or an e-ink display screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0188] Those skilled in the art will understand that Figure 9 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0189] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the following steps:

[0190] Sequentially obtain the two-dimensional grayscale image corresponding to each layer of the inscribed object;

[0191] The inscription image data of each inscription point is obtained based on the two-dimensional grayscale image;

[0192] The displacement stage is sequentially moved to the starting position corresponding to each row of writing points and moved according to the specified program. When the displacement stage reaches the specified position, the digital micromirror is controlled to perform parallel laser writing operation based on the writing image data of the corresponding writing points.

[0193] In another embodiment, this application also discloses a three-dimensional laser writing system, the system comprising: a writing laser for emitting writing laser light; a beam expander for expanding the writing laser beam; a digital micromirror for parallel writing beams and adjusting the light intensity by the number of micromirrors activated; a microlens array for generating parallel writing points; a lens system for focusing the parallel writing beams onto a photolithographic sample; a translational motion mechanism for realizing horizontal and vertical movement of the sample; and a computer for implementing the steps of the method in any of the above embodiments.

[0194] Please see Figure 10 , Figure 10 This is a schematic diagram of the structure of a three-dimensional laser engraving system according to an embodiment of this application.

[0195] Specifically, such as Figure 10 As shown, the 3D laser writing system includes: 1. a 780nm femtosecond laser; 2. a 780nm half-wave plate; 3-4. a reflecting mirror; 5-6. a beam expander composed of two lenses; 7-8. a reflecting mirror; 9. a digital micromirror; 10. a microlens array; 11. a field lens; 12. a dichroic mirror; 13. a high-NA objective lens; 14. photoresist; 15. a piezoelectric displacement stage (Z-axis); 16. an air-bearing displacement stage (XY-axis); 17. an equal-ratio beam divider; 18. an imaging lens; 19. a camera; 20. a condenser lens; 21. an aperture; 22. an illumination source; and 23. a computer.

[0196] Specifically, such as Figure 10As shown, a 780nm femtosecond laser 1 generates a 780nm femtosecond laser beam, which is polarized by a 780nm half-wave plate 2. After the laser direction is adjusted by mirrors 3 and 4, it enters the beam-expanding lens group 5-6 to complete the beam expansion. Subsequently, the laser is reflected by mirrors 7 and 8 and incident on the digital micromirror 9, and then passes through the microlens array 10 to generate a two-dimensional dot matrix. Spatially, a magnified view of one lens in the microlens array 10 is shown. Each microlens (circular area in the figure) corresponds to a region of the digital micromirror, which can be divided into a normally closed region (black square area in the figure) and a modulation region (white square area in the figure). In the normally closed region, all micromirrors are in a normally closed state, and the reflected light does not enter the photoresist 14. The modulation region is equipped with 16*16=256 micromirrors, which can achieve 256 levels of modulation of the reflected light intensity. The size of the microlenses needs to cover the modulation region of the digital micromirror. The two-dimensional dot matrix generated by the microlens array 10 is reflected by the field lens 11 and the dichroic mirror 12 and enters the objective lens 13, where it is focused onto the photoresist sample 14. The piezoelectric displacement stage 15 and the air bearing displacement stage 16 perform scanning motion under program control.

[0197] For example, the translational motion mechanism in this embodiment includes, but is not limited to, the following devices: piezoelectric displacement stage, air bearing displacement stage, mechanical electric displacement stage, manual displacement stage, and combinations containing at least one of the above devices.

[0198] Specifically, such as Figure 10 As shown, the illumination source 22 uses an LED lamp. The emitted illumination light is converted into quasi-parallel light by the condenser lens 20 after passing through the aperture 21. After being reflected by the beam splitter 17, it passes sequentially through the dichroic mirror 12 and the high-NA objective lens 13 before being incident on the sample. In addition, the image at the sample is sequentially imaged onto the camera 19 through the high-NA objective lens 13, the dichroic mirror 12, the beam splitter 17, and the imaging lens 18 for writing observation. The computer 23 acts as the host computer to control the writing program.

[0199] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0200] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0201] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0202] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A three-dimensional laser engraving method, characterized in that, The method includes: Sequentially obtain the two-dimensional grayscale image corresponding to each layer of the inscribed object; Based on the two-dimensional grayscale image, obtain the inscription image data for each inscription point; The displacement stage is sequentially controlled to move to the starting position corresponding to each row of writing points and the displacement stage is controlled to move according to a specified program. When the displacement stage reaches the specified position, the digital micromirror is controlled to perform parallel laser writing operation based on the writing image data of the corresponding writing point. After obtaining the two-dimensional grayscale image corresponding to each layer of the inscribed object, the process also includes: The two-dimensional grayscale image is interpolated to obtain a pixelated grayscale image, the resolution of which is determined based on the writing length and pixel size.

2. The three-dimensional laser engraving method according to claim 1, characterized in that, After sequentially obtaining the two-dimensional grayscale image corresponding to each layer of the inscribed object, the process also includes: If the pixel value of the two-dimensional grayscale image is 0, then the pixel value of the two-dimensional grayscale image is inverted to obtain an inverted grayscale image. Based on the slice layer number corresponding to the two-dimensional grayscale image and the total number of slice layers, the pixel values ​​of the inverted grayscale image are adjusted to obtain grayscale writing data.

3. The three-dimensional laser engraving method according to claim 2, characterized in that, The step of obtaining the inscription image data for each inscription point based on the two-dimensional grayscale image includes: The grayscale writing data corresponding to the two-dimensional grayscale image is split to obtain multiple writing point writing data; Based on the parameters of the digital micromirror, the writing data of each writing point is converted to obtain the writing image data.

4. The three-dimensional laser engraving method according to claim 3, characterized in that, The process of obtaining writing data for multiple writing points includes: Extract each column of the grayscale writing data to obtain multiple columns of writing data; The number of interleaving points in the column direction is calculated based on the number of writing points in the column direction, the pixel size, and the spacing between adjacent light rays in the column direction at the focal plane of the objective lens. Based on the number of column direction interleavings, the column direction zero-padding operation is performed sequentially on the column writing point writing data in each column writing data; Perform a size normalization operation on the zero-padded column write points; Extract each row of the grayscale writing data after the normalization operation to obtain multiple rows of writing data; The number of interleavings in the row direction is calculated based on the number of writing points in the row direction, the pixel size, and the spacing between adjacent light rays in the row direction at the focal plane of the object distance. Based on the number of row direction interleavings, row direction zero padding is performed sequentially on the row writing point writing data in each row writing data; The size of the zero-padded line writing data is normalized to obtain the writing data of the writing points.

5. The three-dimensional laser engraving method according to claim 3, characterized in that, The parameters of the digital micromirror include at least the number of effective projection units and the total number of projection units.

6. The three-dimensional laser engraving method according to claim 1, characterized in that, The control of the displacement stage to move according to a specified program includes: If the current row is an even number of rows, the inscribed image data is sorted in ascending order based on the column number of the inscription point, and the displacement stage is controlled to move in the first direction. If the current row is an odd number of rows, the inscribed image data is sorted in descending order based on the column number of the inscription point, and the displacement stage is controlled to move in a second direction, the first direction being opposite to the second direction.

7. A three-dimensional laser engraving device, characterized in that, The device includes: The first acquisition module is used to sequentially acquire the two-dimensional grayscale image corresponding to each layer of the inscribed object; The second acquisition module is used to acquire the inscription image data of each inscription point based on the two-dimensional grayscale image; The writing module is used to sequentially control the displacement stage to move to the starting position corresponding to each row of writing points and control the displacement stage to move according to a specified program. When the displacement stage reaches the specified position, the digital micromirror is controlled to perform parallel laser writing operation based on the writing image data of the corresponding writing points. An interpolation module is used to perform interpolation processing on the two-dimensional grayscale image to obtain a pixelated grayscale image. The resolution of the pixelated grayscale image is determined based on the writing length and pixel size.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.

9. A three-dimensional laser engraving system, characterized in that, The system includes: A writing laser is used to emit writing laser light; A beam expander is used to expand the laser beam used for writing. Digital micromirrors are used to write light beams in parallel and adjust the light intensity by the number of micromirrors that are turned on. Microlens arrays are used to generate parallel writing points; A lens system is used to focus the parallel writing beams onto the photolithographic sample; Translational motion mechanism, used to achieve horizontal and vertical movement of the sample; A computer for implementing the steps of the method according to any one of claims 1-6.

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