A light-curing printing method, device, electronic equipment and medium

Abstract

The application discloses a kind of photocuring printing method, device, electronic equipment and medium.The method comprises: three-dimensional digital model is sliced, and a plurality of model cut layers are obtained;Based on the preset photocuring forming working curve and exposure parameter, determine the redundant solidification layer number;For current model cut layer, based on the redundant solidification layer number, current model cut layer is divided, and a plurality of forming regions are obtained;Based on a plurality of forming regions and the redundant solidification layer number, determine a plurality of progressive mask images, based on the photocuring forming working curve, the solidified model thickness information, the expected printing thickness and exposure parameter determine the first exposure duration corresponding to a plurality of forming regions respectively;Based on the first exposure duration, determine the second exposure duration corresponding to a plurality of progressive mask images respectively;Based on the second exposure duration, progressive mask image is exposed and printed, and photocuring solid model is obtained;A plurality of model cut layers are printed, and three-dimensional solid model is obtained, to realize the accurate printing of three-dimensional solid model.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and more particularly to a photopolymerization printing method, apparatus, electronic device, and medium. Background Technology

[0002] Photopolymerization printing, as a core process of high-precision additive manufacturing, is widely used in medical, precision manufacturing, and aerospace fields due to its advantages such as high forming accuracy, ability to manufacture complex structures, compatibility with various materials, and fast customization. To improve interlayer bonding and avoid delamination and warping, an over-curing process is typically used, where the exposure energy of a single layer exceeds the curing threshold of the printing material. However, this method has drawbacks: excessive light energy can easily cause unintended curing in uncured areas, resulting in low precision in the printed model. Furthermore, the penetrating nature of the exposure light allows it to travel upwards through the underlying cured layer, potentially causing parasitic curing in the gaps between layers, further reducing the precision of the printed model.

[0003] In existing technologies, grayscale partitioning is commonly used to reduce unnecessary curing of solid models. However, due to the limited grayscale levels in photopolymer printing equipment, only a small number of exposure levels can be defined, making it impossible to achieve fine-grained light control and resulting in low accuracy of the solid model. Furthermore, grayscale partitioning conflicts with grayscale adjustment processes: the grayscale reduction operation of grayscale partitioning disrupts the smooth grayscale gradient required for edge anti-aliasing, causing jagged edges on the single-layer projection plane contour; simultaneously, when combined with mask correction for uniform light intensity on the printing plate, the grayscale of the same pixel is doubled, making it impossible to accurately predict the actual exposure energy and easily leading to insufficient curing, further affecting the accuracy of the solid model. Summary of the Invention

[0004] This invention provides a photopolymerization printing method, apparatus, electronic device, and medium to achieve precise photopolymerization printing.

[0005] According to one aspect of the present invention, a photopolymerization printing method is provided, comprising: Obtain the 3D digital model to be printed, slice the 3D digital model to obtain multiple model slices; Obtain the photopolymerization molding working curve and exposure parameters; determine the number of redundant curing layers based on the photopolymerization molding working curve and exposure parameters; For the current model layer, the current model layer is divided into regions based on the cured model layers that match the number of redundant cured layers, resulting in multiple forming regions. Based on the multiple forming regions and the number of redundant cured layers, multiple progressive mask images corresponding to the current model layer are determined, and the thickness information of the cured model is obtained. Based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model layer, and the exposure parameters, the first exposure time corresponding to each of the multiple forming regions is determined. Based on the first exposure time corresponding to each of the multiple forming regions, the second exposure time corresponding to each of the multiple progressive mask images is determined. Based on the second exposure time and the exposure parameters, the multiple progressive mask images are sequentially exposed and printed to obtain the photopolymerized solid model of the current model layer. After exposing and printing each layer of the model layer by layer, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained.

[0006] According to another aspect of the present invention, a photopolymerization printing apparatus is provided, comprising: The model slicing layer determination module is used to obtain the 3D digital model to be printed, slice the 3D digital model, and obtain multiple model slices. The module for determining redundant curing layers is used to acquire the photocuring working curve and exposure parameters; and to determine the number of redundant curing layers based on the photocuring working curve and exposure parameters. The photopolymer solid model printing module is used to divide the current model slice into regions based on the number of cured model slices that match the number of redundant cured layers, resulting in multiple forming regions; determine multiple progressive mask images corresponding to the current model slice based on the multiple forming regions and the number of redundant cured layers, obtain the thickness information of the cured model, determine the first exposure time corresponding to each of the multiple forming regions based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model slice, and exposure parameters; determine the second exposure time corresponding to each of the multiple progressive mask images based on the first exposure time corresponding to each of the multiple forming regions; and sequentially expose and print the multiple progressive mask images based on the second exposure time and exposure parameters to obtain the photopolymer solid model of the current model slice. The 3D solid model determination module is used to obtain the 3D solid model corresponding to the 3D digital model by performing layer-by-layer exposure printing on multiple model slices.

[0007] According to another aspect of the present invention, an electronic device is provided, the electronic device comprising: At least one processor; and A memory that is communicatively connected to at least one processor; wherein, The memory stores a computer program that can be executed by at least one processor, such that the at least one processor can perform the photopolymerization printing method according to any embodiment of the present invention.

[0008] According to another aspect of the present invention, a computer-readable storage medium is provided, which stores computer instructions for causing a processor to execute and implement the photopolymerization printing method of any embodiment of the present invention.

[0009] According to another aspect of the present invention, a computer program product is provided, comprising a computer program that, when executed by a processor, implements a photopolymerization printing method as described in any embodiment of the present invention.

[0010] The technical solution of this invention acquires a three-dimensional digital model to be printed, slices the model to obtain multiple model slices, providing comprehensive data support for subsequent analysis and processing; acquires the photopolymerization molding working curve and exposure parameters, and determines the number of redundant curing layers based on the working curve and exposure parameters, quantitatively determining the number of slices with interference from suspended structures, providing a quantitative hierarchical basis for subsequent analysis and processing; for the current model slice, the current model slice is divided into regions based on the cured model slices that match the number of redundant curing layers, obtaining multiple forming regions; based on the multiple forming regions and the number of redundant curing layers, multiple progressive mask images corresponding to the current model slice are determined, and the thickness information of the cured model is acquired; based on the photopolymerization molding working curve, the thickness information of the cured model, and the expected printing thickness of the current model slice, the solution is then applied. The first exposure time corresponding to multiple forming areas is determined based on the exposure parameters. The second exposure time corresponding to multiple progressive mask images is then determined based on the first exposure time of each forming area. Based on the second exposure time and exposure parameters, the multiple progressive mask images are sequentially exposed and printed to obtain the photocured solid model of the current model layer. This achieves layered, zoned, and timed exposure printing of the current model layer, improving the printing accuracy of the photocured solid model and suppressing warping and dimensional deviations caused by excessive curing of multiple layers. It also achieves zoned adaptive exposure, balancing the solid forming quality with the printing accuracy of suspended parts. After layer-by-layer exposure printing of multiple model layers, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained. This solves the problem of low accuracy of the three-dimensional solid model in existing technologies that use grayscale zoning for curing printing, thus improving the accuracy of the three-dimensional solid model.

[0011] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a schematic diagram illustrating the principle of photopolymerization printing in the prior art, provided by an embodiment of the present invention; Figure 2 This is a flowchart of a photopolymerization printing method provided in an embodiment of the present invention; Figure 3 This is a flowchart of another photopolymerization printing method provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a photopolymerization printing device provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0014] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0015] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0016] In the process of printing 3D solid models using photopolymerization printing equipment, over-curing is typically used to improve interlayer adhesion and prevent delamination and warping. This involves exposing a single layer to an energy higher than the curing threshold of the printing material. However, this method has drawbacks: excessive light energy can cause unintended curing in uncured areas, resulting in low accuracy in the printed solid model. For an example, see [link to example]. Figure 1 , Figure 1 This is a schematic diagram illustrating the principle of photopolymer printing in the prior art, as provided in an embodiment of the present invention. Exposure light has penetrating properties, allowing it to propagate upwards through the underlying curing layer. This can easily lead to parasitic curing in the gaps between suspended spaces, reducing the accuracy of the three-dimensional solid model. Based on these shortcomings, the present invention proposes a photopolymer printing method, apparatus, electronic device, and medium to achieve precise photopolymer printing.

[0017] Figure 2 This is a flowchart of a photopolymerization printing method provided in an embodiment of the present invention. This embodiment is applicable to photopolymerization printing. The method can be executed by a photopolymerization printing device, which can be implemented in hardware and / or software. This device can be configured in the electronic device provided in this embodiment, which can be a server, computer, or mobile terminal, such as a mobile phone or tablet computer. Figure 2 As shown, the method specifically includes the following steps: S110. Obtain the 3D digital model to be printed, and slice the 3D digital model to obtain multiple model slices.

[0018] The 3D digital model is a digital model describing the structure and dimensions of the target printed part. Optionally, the format of the 3D digital model includes, but is not limited to, stereolithography (STL) format. Optionally, the 3D digital model can be a closed triangular mesh digital model. Model slicing refers to the layered structure obtained by slicing the 3D digital model. The 3D digital model can be determined based on the unique identification information of the target printed part. For example, matching the unique identification information of the target printed part in a 3D digital model database yields the corresponding 3D digital model. The 3D digital model database stores 3D digital models of different printed parts. Slicing the 3D digital model can be performed along the direction perpendicular to the printing direction.

[0019] It should be noted that different model slices have the same slice thickness.

[0020] Specifically, the unique identifier of the target printed part is matched in the 3D digital model database to obtain the corresponding 3D digital model; the 3D digital model is sliced ​​along the direction perpendicular to the printing process to obtain multiple model layers, providing comprehensive data support for subsequent analysis and processing.

[0021] S120. Obtain the photocuring working curve and exposure parameters; determine the number of redundant curing layers based on the photocuring working curve and exposure parameters.

[0022] The photopolymerization molding working curve describes the logarithmic relationship between exposure energy and the curing depth of the printing material. The process for determining the photopolymerization molding working curve is as follows: First, determine the photopolymerization printing equipment and printing material corresponding to the 3D digital model. Then, based on the light intensity of the photopolymerization printing equipment, expose and print multiple test 3D models of different thicknesses for different exposure times to obtain test entity models corresponding to each test 3D model. Next, obtain the test curing thickness of the test entity model. Multiply the light intensity corresponding to each exposure by the exposure time to obtain the exposure energy, and calculate the natural logarithm of the exposure energy. Finally, perform linear regression fitting between the logarithmic exposure energy and the corresponding test curing thickness to obtain the photopolymerization molding working curve. The photopolymerization molding working curve can also be determined based on the light intensity in the exposure parameters. For example, by matching the printing material and light intensity in a photopolymerization molding working curve database, a photopolymerization molding working curve matching the printing material and light intensity can be obtained. This database stores photopolymerization molding working curves matching different printing materials and light intensities. It should be noted that this includes, but is not limited to, bottom-exposure pull-down photopolymerization printing equipment and top-exposure pull-up photopolymerization printing equipment.

[0023] Exposure parameters are the process configuration parameters that drive the photopolymerization printing equipment to perform the forming process. Optionally, exposure parameters include light intensity. Exposure parameters can be preset and set according to requirements; this invention does not impose any limitations on this. The number of excess cured layers is the number of printed material layers that the exposure light can penetrate. The number of excess cured layers can be determined based on the photopolymerization working curve and exposure parameters. For example, the photopolymerization working curve and exposure parameters can be input into a trained excess cured layer determination model for processing to obtain the excess cured layer number. The excess cured layer determination model includes, but is not limited to, neural network models and mathematical models. The excess cured layer determination model can be selected according to requirements; this invention does not impose any limitations on this.

[0024] Specifically, the printing material and light intensity are matched in the photocuring working curve database to obtain a photocuring working curve that matches the printing material and light intensity; the exposure parameters are preset according to the requirements; the photocuring working curve and exposure parameters are input into the trained redundant curing layer determination model for processing to obtain the redundant curing layer number, which can quantitatively determine the number of slice layers that interfere with the suspended structure, providing a quantitative hierarchical basis for subsequent analysis and processing.

[0025] S130. For the current model slice, the current model slice is divided into regions based on the cured model slice that matches the number of redundant cured layers, resulting in multiple forming regions. Based on the multiple forming regions and the number of redundant cured layers, multiple progressive mask images corresponding to the current model slice are determined, and the thickness information of the cured model is obtained. Based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model slice, and the exposure parameters, the first exposure time corresponding to each of the multiple forming regions is determined. Based on the first exposure time corresponding to each of the multiple forming regions, the second exposure time corresponding to each of the multiple progressive mask images is determined. Based on the second exposure time and the exposure parameters, the multiple progressive mask images are exposed and printed sequentially to obtain the photopolymerized solid model of the current model slice.

[0026] In this context, the current model slice is the slice structure that needs to be printed. The cured model slice is the model slice that has been cured and printed. A cured model slice can be a single layer or multiple layers. The number of cured model slices can be determined based on the number of redundant cured layers; for example, the number of cured model slices can be the number of redundant cured layers plus one. The forming region is the area range obtained by dividing the current model slice into regions. Optionally, multiple forming regions include solid regions and at least one multi-level redundant cured regions. The solid region is the slice range in the current model slice where there is no redundant cured layer. The multi-level redundant cured region is the suspended range in the current model slice relative to the cured model slice. The forming region can be obtained by dividing the current model slice into regions based on the number of cured model slices that match the number of redundant cured layers. For example, the current model slice and the cured model slices that match the number of redundant cured layers can be input into a trained region division model for processing to obtain multiple forming regions of the current model slice. The region division model includes, but is not limited to, a neural network model. The region division model is selected according to requirements, and this invention is not limited to this.

[0027] A progressive mask image is a projection image obtained by superimposing multiple layers of redundant solidified regions on a solid region. The progressive mask image can be determined based on multiple formed regions and the number of redundant solidified layers. For example, multiple formed regions and the number of redundant solidified layers are input into a trained progressive mask image generation model for processing to obtain multiple progressive mask images corresponding to the current model's slice layer. The progressive mask image generation model includes, but is not limited to, neural network models. The progressive mask image generation model is selected according to requirements, and this invention does not impose any limitations.

[0028] The cured model thickness information refers to the thickness of the solid model corresponding to the cut layers of the model that have completed photopolymerization printing. Optionally, the cured model thickness information includes the cured model thickness information corresponding to multiple molding areas respectively. The cured model thickness information can be obtained by measurement. For example, the total thickness of the solid model of the cut layers of the model that have completed photopolymerization printing can be measured, and the total thickness of the solid model of the cut layers of the model that have completed photopolymerization printing can be used as the cured model thickness information.

[0029] The expected printing thickness is the desired printing thickness of the model's cut layers. It should be noted that different model cut layers have the same expected printing thickness. The first exposure duration is the safe limit exposure duration corresponding to the forming area. The first exposure duration can be determined based on the photopolymerization working curve, the cured model thickness information, the expected printing thickness of the current model cut layer, and exposure parameters. For example, the parameters of the photopolymerization working curve, the cured model thickness information, the expected printing thickness of the current model cut layer, and exposure parameters are input into a trained first exposure duration determination model for processing to obtain the first exposure duration. The first exposure duration determination model includes, but is not limited to, neural network models and mathematical models. The first exposure duration determination model is selected according to requirements; this invention does not impose any limitations. The second exposure duration is the exposure duration for the progressive mask image. The second exposure durations corresponding to different progressive mask images can be the same or different.

[0030] The photopolymer solid model is the three-dimensional solid structure formed by cutting and curing the current model into layers. It should be noted that the photopolymer solid model corresponding to the current model layer and the solid structure obtained by cutting and curing the cured model into layers are bonded and stacked.

[0031] Specifically, for the current model slice, the current model slice and the already cured model slice matching the number of redundant cured layers are input into the trained region partitioning model for processing to obtain multiple forming regions of the current model slice; the multiple forming regions and the number of redundant cured layers are input into the trained progressive mask image generation model for processing to obtain multiple progressive mask images corresponding to the current model slice; the total thickness of the solid model of the completed photocurable printed model slice is measured, and the total thickness of the solid model of the completed photocurable printed model slice is used as the thickness information of the cured model; the parameters of the photocurable molding working curve, the thickness information of the cured model, and the current model are used to form the solid model of the photocurable printing working curve. The desired printing thickness and exposure parameters of the cut layer are input into the trained first exposure time determination model for processing to obtain the first exposure time. Based on the first exposure time corresponding to multiple forming regions, the second exposure time corresponding to multiple progressive mask images is determined. The photopolymerization printing device sequentially exposes and prints multiple progressive mask images according to the second exposure time and exposure parameters to obtain the photopolymerization solid model of the current model cut layer. This realizes the layered, zoned, and timed exposure printing of the current model cut layer, which can improve the printing accuracy of the photopolymerization solid model and suppress warping and dimensional deviation caused by multiple superimposed and redundant curing. It also achieves zoned adaptive exposure, taking into account both the solid forming quality and the printing accuracy of the suspended parts.

[0032] Based on the above embodiments, the method further includes: exposing and printing multiple molding areas separately based on the first exposure time corresponding to each molding area to obtain a photocurable solid model of the current model layer.

[0033] Optionally, multiple progressive mask images corresponding to the current model slice layer are determined based on multiple forming regions and the number of redundant curing layers, including: performing mask processing on multiple forming regions based on the number of redundant curing layers to obtain solid mask regions and multi-level redundant curing mask regions, where the solid mask region is the light transmission range corresponding to the solid region, and the multi-level redundant curing mask region is the light transmission range of at least one multi-level redundant curing region; using the solid mask region as the light transmission base region, multi-level redundant curing mask regions of different levels are progressively superimposed in descending order of the number of layers, and each superimposed multi-level redundant curing mask region yields a set of superimposed light transmission regions; generating solid mask images and superimposed light transmission mask images based on the solid mask regions and superimposed light transmission regions, respectively; and determining multiple progressive mask images corresponding to the current model slice layer based on the solid mask images and superimposed light transmission mask images.

[0034] The solid mask region is the light-transmitting contour range mapped from the solid region to the projection mask layer. When performing binary mask mapping on the solid region, the region corresponding to the solid region is converted into the mask's light-transmitting range, resulting in the solid mask region. The multi-level redundant curing mask region is the light-transmitting contour range mapped from the multi-level redundant curing region to the projection mask layer. When performing binary mask mapping on the multi-level redundant curing region, the region corresponding to the multi-level redundant curing region is converted into the mask's light-transmitting range, resulting in the multi-level redundant curing mask region.

[0035] The superimposed transparent area is the range of light transmission obtained by superimposing multiple layers of redundant curing mask areas onto a solid mask area as the base. It should be noted that the order in which the multiple layers of redundant curing mask areas are superimposed follows a decreasing order of the number of layers in the multiple layers of redundant curing mask areas. The number of layers in the multiple layers of redundant curing mask areas refers to the number of slice layers in the multiple layers of redundant curing mask areas where there is redundant curing interference. For example, if the number of layers corresponding to m multiple layers of redundant curing mask areas are n1, n2, ..., nm, and n1, n2, ..., nm are sorted in descending order, the descending order of the number of layers corresponds to the superposition order of the m multiple layers of redundant curing mask areas.

[0036] A solid mask image is a projected image containing only the light-transmitting area of ​​the solid mask region. A superimposed light-transmitting mask image is a projected image including the light-transmitting area of ​​both the solid mask region and the light-transmitting areas of multiple redundant cured mask layers.

[0037] Specifically, a binary mask transformation is performed on the solid region to obtain the solid mask region, and a binary mask transformation is performed on the multi-level redundant solidified regions to obtain the multi-level redundant solidified mask regions. Using the solid mask region as the base region for light transmission, multi-level redundant solidified mask regions of different levels are progressively superimposed in descending order of the number of levels. Each superimposed layer of multi-level redundant solidified mask regions yields a set of superimposed light-transmitting regions. The contour data of the solid mask region and the superimposed light-transmitting regions are extracted separately and converted into binary projection images to obtain the solid mask image and the superimposed light-transmitting mask image. The solid mask image and the superimposed light-transmitting mask image are used as multiple progressive mask images corresponding to the current model layer, realizing the accurate determination of progressive mask images and providing comprehensive and accurate image support for subsequent analysis and processing.

[0038] Optionally, determining the second exposure duration corresponding to each of the multiple progressive mask images based on the first exposure duration corresponding to each of the multiple forming regions includes: for a physical mask image, obtaining the expected exposure duration of the physical region; determining the second exposure duration of the physical mask image based on the expected exposure duration and the first exposure duration of the first superimposed transparent region; for the current superimposed transparent mask image, obtaining the first exposure duration of the current superimposed transparent mask image and the first exposure duration of the next level of superimposed transparent masks; determining the second exposure duration corresponding to the current superimposed transparent mask image based on the difference between the first exposure duration of the current superimposed transparent mask image and the first exposure duration of the next level of superimposed transparent masks; wherein, the sum of the second exposure duration of the physical mask image and the second exposure duration of the multiple superimposed transparent masks is the expected exposure duration of the physical mask image.

[0039] The expected exposure time is the exposure time of the solid region in the current model slice layer, which can be preset. The second exposure time of the solid mask image can be determined based on the expected exposure time and the first exposure time of the first superimposed transparent region. For example, the difference between the expected exposure time and the first exposure time of the first superimposed transparent region can be calculated, and this difference can be used as the second exposure time of the solid mask image. The second exposure time corresponding to the current superimposed transparent mask can be determined based on the first exposure time of the current superimposed transparent mask and the first exposure time of the next level of superimposed transparent masks. For example, the difference between the first exposure time of the current superimposed transparent mask and the first exposure time of the next level of superimposed transparent masks can be calculated, and this difference can be used as the second exposure time corresponding to the current superimposed transparent mask.

[0040] It should be noted that the sum of the second exposure time of the physical mask image and the second exposure time of multiple superimposed transparent masks is the expected exposure time of the physical mask image.

[0041] Specifically, the expected exposure time for the physical region is preset, and the difference between the expected exposure time and the first exposure time of the first superimposed transparent region is calculated. This difference is used as the second exposure time of the physical mask image. The first exposure time of the current superimposed transparent mask and the first exposure time of the next level of superimposed transparent masks are obtained, and the difference between these two is calculated. This difference is used as the second exposure time of the current superimposed transparent mask, and so on. The first exposure time of the superimposed transparent mask of the last superimposed multi-level redundant curing mask region is used as the second exposure time of the last superimposed multi-level redundant curing mask region. This process achieves precise determination of the exposure time for different exposure images, providing accurate data support for subsequent exposure printing.

[0042] For example, the formula for calculating the second exposure time of the physical mask image is as follows: ; in, This indicates the second exposure duration of the physical mask image; Indicates the expected exposure time for the physical area; This indicates the first exposure duration of the first superimposed transparent area; The formula for calculating the second exposure time corresponding to the superimposed light-transmitting mask is as follows: ; in, This represents the second exposure time corresponding to the p-th superimposed light-transmitting mask; This represents the first exposure time corresponding to the p-th superimposed light-transmitting mask; This indicates the first exposure time corresponding to the (p-1)th superimposed light transmission mask; it should be noted that the (p-1)th superimposed light transmission mask is the next level of superimposed light transmission masks after the pth superimposed light transmission mask.

[0043] Optionally, the current model layer is region-divided based on the cured model layers that match the number of redundant cured layers, including: using the current model layer as a reference, tracing back to the cured model layers that match the number of redundant cured layers; determining the redundant cured regions of adjacent layers in the cured model layers; determining the redundant cured regions of the current model layer based on the current model layer and the previous model layer; projecting the redundant cured regions of adjacent layers in the cured model layers onto the current model layer to obtain the cured projected region; determining the multi-level redundant cured regions corresponding to the current model layer based on the cured projected region and the redundant cured regions of the current model layer; and dividing the current model layer into regions based on the multi-level redundant cured regions to obtain the solid region and the multi-level redundant cured regions.

[0044] Among them, "cured model layers" refers to model layers that have completed curing and printing. A "cured model layer matching the number of redundant cured layers" can be a cured model layer whose number of traced slices matches the number of redundant cured layers, based on the current model layer. For example, if the number of redundant cured layers is C, the number of cured model layers matching this number could be C+1. The redundant cured region is the area within a model layer containing solid regions, but not within the previous model layer. Adjacent layers are two cured model layers directly stacked along the printing direction. The process for determining the redundant cured area of ​​any group of adjacent cut layers in a cured model is as follows: Based on the printing order of the model cut layers, the cured model cut layer that is printed earlier in the order is taken as the previous cured model cut layer, and the cured model cut layer that is printed later in the order is taken as the next cured model cut layer; Boolean operation is performed on the outline range of the next cured model cut layer and the outline range of the previous cured model cut layer to filter out the range in which the next cured model cut layer has a solid area and the previous cured model cut layer does not have a solid area at the same position. The range selected above is taken as the redundant cured area corresponding to the next cured model cut layer.

[0045] The redundant solidified region of the current model layer is the area where there is a solid region in the current model layer but no solid region in the previous model layer. It should be noted that the previous model layer corresponding to the current model layer is determined based on the printing order of multiple model layers. For example, if the printing order of the current model layer is 'a', the printing order of the previous model layer corresponding to the current model layer is 'a-1'. The process of determining the redundant solidified region of the current model layer is as follows: Boolean operations are performed on the outline range of the current model layer and the outline range of the previous model layer to filter out the range where there is a solid region in the current model layer but no solid region in the previous model layer at the same position. This range is then defined as the redundant solidified region of the current model layer.

[0046] The solidified projection area is the range obtained by projecting the excess solidified areas of adjacent layers in the solidified model to the current model layer. It should be noted that projecting the excess solidified areas of adjacent layers in the solidified model to the current model layer can be done by projecting the excess solidified areas of adjacent layers in the solidified model to the current model layer along a direction perpendicular to the printing direction.

[0047] The multi-level redundant solidified region is a composite suspended area in the current model slice that merges the solidified projection region corresponding to the solidified model slice and the redundant solidified region of the current model slice. For example, the solidified projection region and the redundant solidified region of the current model slice are taken as the multi-level redundant solidified region corresponding to the current model slice.

[0048] The current model layer is divided into regions based on the multi-level redundant solidified regions, resulting in solid regions and multi-level redundant solidified regions. Alternatively, the multi-level redundant solidified regions can be used as the multi-level redundant solidified regions of the current model layer, and the remaining regions can be used as the solid regions of the current model layer.

[0049] Specifically, based on the current model layer, the number of traced slices matches the number of redundant cured layers in the cured model layer; based on the printing order of the model layers, the cured model layer printed earlier is taken as the previous cured model layer, and the cured model layer printed later is taken as the next cured model layer. Boolean operations are performed on the outline range of the next cured model layer and the outline range of the previous cured model layer to filter out the range where the next cured model layer has a solid region and the previous cured model layer does not have a solid region at the same position. This filtered range is taken as the redundant cured region corresponding to the next cured model layer, and so on, to obtain the redundant cured regions of adjacent layers in the cured model layer; the outline range of the current model layer and the previous model layer are then compared. Boolean operations are performed on the contour range of the cut layer to filter out the range where the current model cut layer contains a solid region and the previous model cut layer does not contain a solid region at the same position. This range is then designated as the redundant solidified region of the current model cut layer. The redundant solidified regions of adjacent cut layers in the solidified model cut layer are projected onto the current model cut layer along a direction perpendicular to the printing direction to obtain the solidified projected region. The solidified projected region and the redundant solidified region of the current model cut layer are then designated as the multi-level redundant solidified regions corresponding to the current model cut layer. By designating the multi-level redundant solidified regions as the multi-level redundant solidified regions of the current model cut layer and the remaining regions as the solid regions of the current model cut layer, the precise division of the current model cut layer region is achieved.

[0050] S140. After exposing and printing multiple model layers one by one, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained.

[0051] The 3D solid model is a physical entity obtained by sequentially exposing and printing multiple model layers using a photopolymerization printing device. Specifically, by sequentially exposing and printing multiple model layers using a photopolymerization printing device, a 3D solid model corresponding to the 3D digital model is obtained, thus improving the accuracy of the 3D solid model.

[0052] The technical solution of this embodiment acquires a 3D digital model to be printed, slices the 3D digital model to obtain multiple model slices, providing comprehensive data support for subsequent analysis and processing; acquires the photopolymerization molding working curve and exposure parameters, and determines the number of redundant curing layers based on the photopolymerization molding working curve and exposure parameters, which can quantitatively determine the number of slices with interference from suspended structures, providing a quantitative hierarchical basis for subsequent analysis and processing; for the current model slice, the current model slice is divided into regions based on the cured model slices that match the number of redundant curing layers, obtaining multiple molding regions, and determining multiple progressive mask images corresponding to the current model slice based on the multiple molding regions and the number of redundant curing layers, acquiring the thickness information of the cured model, and based on the photopolymerization molding working curve and the thickness of the cured model... Information, the expected printing thickness of the current model layer, and exposure parameters determine the first exposure time for each of the multiple forming regions. Based on the first exposure time for each of the multiple forming regions, the second exposure time for each of the multiple progressive mask images is determined. Based on the second exposure time and exposure parameters, the multiple progressive mask images are sequentially exposed and printed to obtain the photopolymer solid model of the current model layer. This achieves layer-by-layer, zone-by-zone, and time-by-time exposure printing of the current model layer, which can improve the printing accuracy of the photopolymer solid model and suppress warping and dimensional deviations caused by excessive curing of multiple layers. It also achieves zone-based adaptive exposure, balancing the solid forming quality with the printing accuracy of suspended parts. After layer-by-layer exposure printing of multiple model layers, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained, improving the accuracy of the three-dimensional solid model.

[0053] Figure 3 This is a flowchart of another photopolymerization printing method provided in this embodiment of the invention. This embodiment is a refinement of the above embodiments. Based on the foregoing embodiments, it provides a detailed explanation of determining the first exposure time corresponding to multiple forming regions based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model layer, and exposure parameters. For specific implementation details, please refer to the technical solution of this embodiment. Technical terms that are the same as or corresponding to those in the above embodiments will not be repeated here. Figure 3 As shown, the method specifically includes the following steps: S210. Obtain the three-dimensional digital model to be printed, and slice the three-dimensional digital model to obtain multiple model slices.

[0054] S220. Obtain the photocuring working curve and exposure parameters; determine the number of redundant curing layers based on the photocuring working curve and exposure parameters.

[0055] Optionally, the exposure parameters may also include the expected exposure time for the solid regions in multiple molding areas.

[0056] The expected exposure time is the exposure time of the solid area in the forming area, which can be preset.

[0057] Optionally, the number of redundant curing layers is determined based on the photopolymerization working curve and exposure parameters, including: determining the exposure curing depth based on the photopolymerization working curve, light intensity and expected exposure time; and determining the number of redundant curing layers based on the exposure curing depth and the expected printing thickness of the current model layer.

[0058] The exposure curing depth is the maximum thickness of the printing material that cures upon exposure to light. The exposure curing depth can be determined based on the photopolymerization working curve, light intensity, and desired exposure time. For example, the exposure curing depth can be obtained by matching the light intensity and desired exposure time within the photopolymerization working curve.

[0059] The desired printing thickness is the expected printing thickness of the model cut layer, which can be preset. The number of excess cured layers can also be determined based on the exposure and curing depth and the desired printing thickness of the current model cut layer. For example, the ratio between the exposure and curing depth and the desired printing thickness of the current model cut layer can be calculated, and then rounded down to obtain the number of excess cured layers.

[0060] Specifically, the exposure curing depth is obtained by matching the light intensity and the expected exposure time in the photocuring working curve; the ratio between the exposure curing depth and the expected printing thickness of the current model layer is calculated, and the ratio between the exposure curing depth and the expected printing thickness of the current model layer is rounded down to obtain the number of redundant curing layers. This can quantitatively determine the number of slice layers that cause interference from the suspended structure, providing a quantitative hierarchical basis for subsequent analysis and processing.

[0061] S230. For the current model layer, the current model layer is divided into regions based on the cured model layers that match the number of redundant cured layers, resulting in multiple forming regions. Based on the multiple forming regions and the number of redundant cured layers, multiple progressive mask images corresponding to the current model layer are determined. The thickness information of the cured model is obtained, and the critical exposure energy and material penetration depth information are determined by matching the light intensity and the desired printing thickness in the photopolymerization molding working curve. Based on the material penetration depth information and the cured model thickness information corresponding to the multiple forming regions, the effective penetration depth corresponding to each of the multiple forming regions is determined. Based on the effective penetration depth and the critical exposure energy, a safe exposure energy threshold is determined. Based on the safe exposure energy threshold and the light intensity, a first exposure time is determined. Based on the first exposure time corresponding to each of the multiple forming regions, a second exposure time corresponding to each of the multiple progressive mask images is determined. Based on the second exposure time and the exposure parameters, the multiple progressive mask images are sequentially exposed and printed to obtain the photopolymerized solid model of the current model layer.

[0062] The critical exposure energy is the minimum incident exposure energy required for the printing material to undergo a curing reaction. The material penetration depth information is the theoretically permeable scale of the exposure light in the pure liquid, uncured printing material when its intensity attenuates to 1 / e of the surface light intensity, characterizing the inherent optical attenuation properties of the printing material. The critical exposure energy and material penetration depth information can be obtained by matching the light intensity and desired printing thickness within the photopolymerization working curve.

[0063] The effective penetration depth is the scale of the solid model corresponding to the thickness information of the cured model through which the exposed light penetrates. The effective penetration depth corresponding to the forming area can be determined based on the material penetration depth information and the thickness information of the cured model. For example, for any forming area, the material penetration depth information and the thickness information of the cured model corresponding to that forming area are input into a trained effective penetration depth determination model for processing to obtain the effective penetration depth corresponding to that forming area. The effective penetration depth determination model includes, but is not limited to, neural network models and mathematical models. The effective penetration depth determination model is selected according to the requirements, and this invention does not impose any restrictions. It should be noted that the effective penetration depths corresponding to different forming areas can be the same or different.

[0064] The safe exposure energy threshold is the maximum permissible incident exposure energy that, after the exposed light penetrates the solid model corresponding to the thickness information of the cured model, the remaining energy cannot generate excess curing energy. The safe exposure energy threshold can be determined based on the effective penetration depth and the critical exposure energy. For example, the effective penetration depth and the critical exposure energy can be input into a trained safe exposure energy threshold determination model for processing to obtain the safe exposure energy threshold. The safe exposure energy threshold determination model includes, but is not limited to, neural network models and mathematical models. The appropriate safe exposure energy threshold determination model can be selected according to requirements; this invention does not impose any limitations.

[0065] The first exposure duration can also be determined based on the safe exposure energy threshold and light intensity. For example, the safe exposure energy threshold and light intensity can be input into a trained first exposure duration determination model for processing to obtain the first exposure duration. The first exposure duration determination model includes, but is not limited to, neural network models and mathematical models. The first exposure duration determination model can be selected according to the requirements, and this invention does not impose any restrictions.

[0066] Specifically, for the current model slice, the current model slice and the cured model slice matching the number of redundant cured layers are input into the trained region partitioning model for processing to obtain multiple forming regions of the current model slice; the multiple forming regions and the number of redundant cured layers are input into the trained progressive mask image generation model for processing to obtain multiple progressive mask images corresponding to the current model slice; the total thickness of the solid model of the completed photocurable printed model slice is measured, and the total thickness of the solid model of the completed photocurable printed model slice is used as the cured model thickness information; the light intensity and the desired printing thickness are matched in the photocurable molding working curve to obtain the critical exposure energy and material penetration depth information; the material penetration depth information and the cured model thickness information corresponding to the forming region are input into the trained effective penetration depth determination model for processing. The effective penetration depth corresponding to the forming area is obtained. The effective penetration depth and critical exposure energy are input into the trained safe exposure energy threshold determination model for processing to obtain the safe exposure energy threshold. The safe exposure energy threshold and light intensity are input into the trained first exposure duration determination model for processing to obtain the first exposure duration. Based on the first exposure duration corresponding to multiple forming areas, the second exposure duration corresponding to multiple progressive mask images is determined. The photopolymerization printing device sequentially exposes and prints multiple progressive mask images according to the second exposure duration and exposure parameters to obtain the photopolymerization solid model of the current model layer. This realizes the layered, zoned, and timed exposure printing of the current model layer, which can improve the printing accuracy of the photopolymerization solid model and suppress warping and dimensional deviation caused by multiple superimposed superposition and excessive curing. It achieves zoned adaptive exposure, taking into account both the solid forming quality and the printing accuracy of the suspended parts.

[0067] For example, the formula for calculating the effective penetration depth is as follows: ; in, Indicates the effective penetration depth; Indicates the depth of material penetration; This indicates the thickness of the solid model corresponding to the thickness information of N-1 solidified models; it should be noted that the current model cut layer is the Nth model cut layer.

[0068] For example, the formula for calculating the safe exposure energy threshold is as follows: ; in, Indicates the safe exposure energy threshold; Indicates the critical exposure energy; Indicates the effective penetration depth.

[0069] For example, the formula for calculating the first exposure duration is as follows: ; in, This indicates the first exposure time corresponding to the Nth forming area; Indicates the safe exposure energy threshold; This represents light intensity; it should be noted that the first exposure time corresponding to the Nth forming area does not include the first exposure time of the solid area; the first exposure time of the solid area is the expected exposure time.

[0070] It should be noted that during the sequential exposure and printing of multiple progressive mask images based on the second exposure duration and exposure parameters, the printing order of the multiple progressive mask images is as follows: solid mask image, followed by superimposed transparent mask images corresponding to multiple layers of redundant solidified mask areas, with the solid mask area as the base area for light transmission, and in descending order of the number of layers. Based on the above printing order of multiple progressive mask images, the photopolymerization printing time for model layer cutting can be effectively reduced, thereby improving the photopolymerization printing efficiency of the entire 3D solid model.

[0071] Optionally, after obtaining the photocured solid model of the current model layer, the method further includes: determining the first incremental curing thickness of the multi-level redundant curing regions in the multiple molding regions based on the critical exposure energy, material penetration depth information, light intensity, and the first exposure time corresponding to the multi-level redundant curing regions in the multiple molding regions; updating the cured model thickness information based on the first incremental curing thickness of the multi-level redundant curing regions in the multiple molding regions to obtain the updated cured model thickness information.

[0072] The first incremental curing thickness is the formed thickness obtained after the multi-level redundant curing regions have undergone exposure and curing using the corresponding first exposure time. The first incremental curing thickness can be determined based on the critical exposure energy, material penetration depth information, light intensity, and the first exposure time. For example, for any multi-level redundant curing region, the critical exposure energy, material penetration depth information, light intensity, and the corresponding first exposure time for that multi-level redundant curing region are input into a trained first incremental curing thickness determination model for processing to obtain the first incremental curing thickness of that multi-level redundant curing region. The first incremental curing thickness determination model includes, but is not limited to, neural network models and mathematical models. The first incremental curing thickness determination model is selected according to requirements, and this invention does not impose any limitations.

[0073] The cured model thickness information can be updated based on the first incremental cured thickness. For example, the sum of the cured model thickness information and the corresponding first incremental cured thickness for each of the multiple molding areas is calculated, and the sum of the cured model thickness information and the corresponding first incremental cured thickness for each of the multiple molding areas is used as the updated cured model thickness information.

[0074] Specifically, the critical exposure energy, material penetration depth information, light intensity, and the first exposure time corresponding to the multi-level redundant curing regions in multiple molding areas are input into the trained first incremental curing thickness determination model for processing, thereby obtaining the first incremental curing thickness corresponding to the multi-level redundant curing regions in multiple molding areas. The sum of the cured model thickness information and the corresponding first incremental curing thickness corresponding to each of the multiple molding areas is calculated, and the sum of the cured model thickness information and the corresponding first incremental curing thickness corresponding to each of the multiple molding areas is used as the updated cured model thickness information. This realizes the update of the cured model thickness information, providing accurate and comprehensive data support for subsequent photopolymerization printing of model layers, which in turn helps to improve the accuracy of the three-dimensional solid model corresponding to the three-dimensional digital model.

[0075] For example, the formula for updating the thickness information of the solidified model is as follows: ; in, This represents the thickness of the solid model corresponding to the thickness information of the first N solidified models, i.e., the updated thickness information of the solidified models. This represents the thickness of the solid model corresponding to the thickness information of the first N-1 solidified models, i.e., the thickness information of the solidified models before the update. This indicates the first incremental solidification thickness; it should be noted that the current model cut layer is the Nth model cut layer.

[0076] Optionally, after obtaining the photocured solid model of the current model slice, the method further includes: determining the second incremental curing thickness corresponding to each of the multiple progressive mask images based on the critical exposure energy, material penetration depth information, light intensity, and the second exposure time corresponding to each of the multiple progressive mask images; updating the cured model thickness information based on the second incremental curing thickness corresponding to each of the multiple progressive mask images to obtain the updated cured model thickness information.

[0077] The second incremental curing thickness is the forming thickness obtained after the progressive mask image has been exposed and cured using the corresponding second exposure time. The second incremental curing thickness can be determined based on the critical exposure energy, material penetration depth information, light intensity, and the second exposure time corresponding to the progressive mask image. For example, for any progressive mask image, the critical exposure energy, material penetration depth information, light intensity, and the second exposure time corresponding to the progressive mask image are input into a trained second incremental curing thickness determination model for processing to obtain the second incremental curing thickness corresponding to the progressive mask image. The second incremental curing thickness determination model includes, but is not limited to, neural network models and mathematical models. The choice of the second incremental curing thickness determination model is based on requirements, and this invention does not impose any limitations.

[0078] The cured model thickness information can also be updated based on the second incremental cured thickness. For example, the sum of the cured model thickness information and the corresponding second incremental cured thickness for each of the multiple molding areas can be calculated, and this sum can be used as the updated cured model thickness information.

[0079] Specifically, the critical exposure energy, material penetration depth information, light intensity, and the second exposure duration corresponding to multiple progressive mask images are input into the trained second incremental curing thickness determination model for processing, thereby obtaining the second incremental curing thickness corresponding to each of the multiple progressive mask images. The sum of the cured model thickness information and the corresponding second incremental curing thickness corresponding to each of the multiple forming regions is calculated, and the sum of the cured model thickness information and the corresponding second incremental curing thickness corresponding to the multiple forming regions is used as the updated cured model thickness information. This realizes the update of the cured model thickness information, providing accurate and comprehensive data support for subsequent photopolymerization printing of model layers, which in turn helps to improve the accuracy of the three-dimensional solid model corresponding to the three-dimensional digital model.

[0080] S240. After exposing and printing multiple model layers one by one, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained.

[0081] The technical solution of this embodiment obtains a three-dimensional digital model to be printed, slices the three-dimensional digital model to obtain multiple model slices, and provides comprehensive data support for subsequent analysis and processing; it obtains the photocuring working curve and exposure parameters, and determines the number of redundant curing layers based on the photocuring working curve and exposure parameters, which can quantitatively determine the number of slices that interfere with the suspended structure, and provides a quantitative hierarchical basis for subsequent analysis and processing. For the current model layer, the current model layer is divided into regions based on the cured model layers that match the number of redundant cured layers, resulting in multiple forming regions. Based on these multiple forming regions and the number of redundant cured layers, multiple progressive mask images corresponding to the current model layer are determined, and the thickness information of the cured model is obtained. Matching is performed on the photopolymerization working curve based on light intensity and desired printing thickness to determine the critical exposure energy and material penetration depth information. Based on the material penetration depth information and the cured model thickness information corresponding to each of the multiple forming regions, the effective penetration depth corresponding to each of the multiple forming regions is determined. Based on the effective penetration depth and critical exposure energy, a safe exposure energy threshold is determined. Based on the safe exposure energy threshold and light... The first exposure time is determined, and the second exposure time corresponding to multiple progressive mask images is determined based on the first exposure time corresponding to multiple forming areas. Based on the second exposure time and exposure parameters, multiple progressive mask images are sequentially exposed and printed to obtain the photocured solid model of the current model layer. This realizes layer-by-layer and zone-by-zone exposure printing of the current model layer, which can improve the printing accuracy of the photocured solid model and suppress warping and dimensional deviation caused by multiple layers of superimposed curing. It achieves zone-adaptive exposure, taking into account both the solid forming quality and the printing accuracy of suspended parts. After exposing and printing multiple model layers layer by layer, the three-dimensional solid model corresponding to the three-dimensional digital model is obtained, which improves the accuracy of the three-dimensional solid model.

[0082] Figure 4 This is a schematic diagram of the structure of a photopolymerization printing device provided in an embodiment of the present invention. Figure 4 As shown, the device includes a model layer determination module 310, a redundant curing layer number determination module 320, a photocurable solid model printing module 330, and a three-dimensional solid model determination module 340.

[0083] The module 310 is used to acquire the 3D digital model to be printed, slice the 3D digital model to obtain multiple model layers; the module 320 is used to acquire the photopolymerization working curve and exposure parameters, and determine the number of redundant curing layers based on the photopolymerization working curve and exposure parameters; the photopolymerization solid model printing module 330 is used to divide the current model layer into regions based on the cured model layers that match the number of redundant curing layers, to obtain multiple forming regions; and determine multiple progressive mask maps corresponding to the current model layer based on the multiple forming regions and the number of redundant curing layers. For example, the module obtains the thickness information of the cured model, and determines the first exposure time corresponding to multiple forming areas based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model layer, and the exposure parameters; it determines the second exposure time corresponding to multiple progressive mask images based on the first exposure time corresponding to the multiple forming areas; it sequentially exposes and prints multiple progressive mask images based on the second exposure time and the exposure parameters to obtain the photopolymerized solid model of the current model layer; the three-dimensional solid model determination module 340 is used to obtain the three-dimensional solid model corresponding to the three-dimensional digital model after exposing and printing multiple model layers layer by layer.

[0084] The technical solution of this embodiment, through a model layer determination module, acquires the 3D digital model to be printed, slices the 3D digital model to obtain multiple model layers, providing comprehensive data support for subsequent analysis and processing; through a redundant curing layer determination module, it acquires the photopolymerization molding working curve and exposure parameters; based on the photopolymerization molding working curve and exposure parameters, it determines the number of redundant curing layers, which can quantitatively determine the number of slice layers interfering with the suspended structure, providing a quantitative hierarchical basis for subsequent analysis and processing; through a photopolymerization solid model printing module, for the current model layer, it divides the current model layer into regions based on the cured model layer that matches the number of redundant curing layers, obtaining multiple molding regions; based on the multiple molding regions and the number of redundant curing layers, it determines multiple progressive mask images corresponding to the current model layer, obtains the thickness information of the cured model, and based on the photopolymerization molding... The working curve, the thickness information of the cured model, the expected printing thickness of the current model layer, and the exposure parameters determine the first exposure time corresponding to each of the multiple forming areas. Based on the first exposure time corresponding to each of the multiple forming areas, the second exposure time corresponding to each of the multiple progressive mask images is determined. Based on the second exposure time and the exposure parameters, the multiple progressive mask images are sequentially exposed and printed to obtain the photocured solid model of the current model layer. This realizes the layered, zoned, and timed exposure printing of the current model layer, which can improve the printing accuracy of the photocured solid model and suppress warping and dimensional deviations caused by multiple layers of superimposed curing. It also achieves zoned adaptive exposure, taking into account both the solid forming quality and the printing accuracy of the suspended parts. Through the 3D solid model determination module, after exposing and printing multiple model layers layer by layer, the 3D solid model corresponding to the 3D digital model is obtained, which improves the accuracy of the 3D solid model.

[0085] Based on the above embodiments, optionally, the cured model thickness information includes the cured model thickness information corresponding to each of the multiple forming areas; the exposure parameters include light intensity; the photocurable solid model printing module 330 is further configured to: match the light intensity and the desired printing thickness in the photocurable molding working curve to determine the critical exposure energy and material penetration depth information; determine the effective penetration depth corresponding to each of the multiple forming areas based on the material penetration depth information and the cured model thickness information corresponding to each of the multiple forming areas; determine the safe exposure energy threshold based on the effective penetration depth and the critical exposure energy; and determine the first exposure time based on the safe exposure energy threshold and the light intensity.

[0086] Optionally, the device further includes a cured model thickness information update module, used to: determine the first incremental curing thickness of the excess curing area in the multiple molding areas based on the critical exposure energy, material penetration depth information, light intensity, and the first exposure time corresponding to the excess curing area in the multiple molding areas; update the cured model thickness information based on the first incremental curing thickness of the excess curing area in the multiple molding areas to obtain the updated cured model thickness information.

[0087] Optionally, the solidified model thickness information update module is also used to: determine the second incremental solidification thickness corresponding to each of the multiple progressive mask images based on the critical exposure energy, material penetration depth information, light intensity, and the second exposure time corresponding to each of the multiple progressive mask images; update the solidified model thickness information based on the second incremental solidification thickness corresponding to each of the multiple progressive mask images to obtain the updated solidified model thickness information.

[0088] Optionally, the exposure parameters also include the expected exposure time for the solid areas in multiple molding regions; the redundant curing layer determination module 320 is also used to: determine the exposure curing depth based on the photopolymerization molding working curve, light intensity and expected exposure time; and determine the redundant curing layer based on the exposure curing depth and the expected printing thickness of the current model cutting layer.

[0089] Optionally, the multiple forming regions include solid regions and at least one multi-level redundant curing regions; the photopolymer solid model printing module 330 is further configured to: perform masking processing on the multiple forming regions based on the number of redundant curing layers to obtain solid mask regions and multi-level redundant curing mask regions, wherein the solid mask regions are the light-transmitting range corresponding to the solid regions, and the multi-level redundant curing mask regions are the light-transmitting range of at least one multi-level redundant curing region; using the solid mask regions as the light-transmitting base regions, multi-level redundant curing mask regions of different levels are sequentially superimposed in descending order of the number of layers, and each superimposed layer of multi-level redundant curing mask regions yields a set of superimposed light-transmitting regions; generate solid mask images and superimposed light-transmitting mask images based on the solid mask regions and superimposed light-transmitting regions respectively; and determine multiple progressive mask images corresponding to the current model cutting layer based on the solid mask images and superimposed light-transmitting mask images.

[0090] Optionally, the photopolymer solid model printing module 330 is further configured to: for a solid mask image, obtain the expected exposure time of the solid region; determine the second exposure time of the solid mask image based on the expected exposure time and the first exposure time of the first superimposed transparent region; for the current superimposed transparent mask image, obtain the first exposure time of the current superimposed transparent mask image and the first exposure time of the next level of superimposed transparent masks image; determine the second exposure time corresponding to the current superimposed transparent mask image based on the difference between the first exposure time of the current superimposed transparent mask image and the first exposure time of the next level of superimposed transparent masks image; wherein, the sum of the second exposure time of the solid mask image and the second exposure time of the multiple superimposed transparent masks image is the expected exposure time of the solid mask image.

[0091] Optionally, the photopolymer solid model printing module 330 is further configured to: trace the cured model layers that match the number of redundant cured layers, based on the current model layer; determine the redundant cured regions of adjacent layers in the cured model layers; determine the redundant cured regions of the current model layer based on the current model layer and the previous model layer; project the redundant cured regions of adjacent layers in the cured model layers onto the current model layer to obtain the cured projected region; determine the multi-level redundant cured regions corresponding to the current model layer based on the cured projected region and the redundant cured regions of the current model layer; and divide the current model layer into regions based on the multi-level redundant cured regions to obtain the solid region and the multi-level redundant cured regions.

[0092] The photopolymerization printing apparatus provided in this embodiment of the invention can execute a photopolymerization printing method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of executing the method.

[0093] Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. The electronic device 10 is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device may also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices (such as helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the invention described and / or claimed herein.

[0094] like Figure 5 As shown, the electronic device 10 includes at least one processor 11 and a memory, such as a read-only memory (ROM) 12 or a random access memory (RAM) 13, communicatively connected to the at least one processor 11. The memory stores computer programs executable by the at least one processor. The processor 11 can perform various appropriate actions and processes based on the computer program stored in the ROM 12 or loaded from storage unit 18 into the RAM 13. The RAM 13 may also store various programs and data required for the operation of the electronic device 10. The processor 11, ROM 12, and RAM 13 are interconnected via a bus 14. An input / output (I / O) interface 15 is also connected to the bus 14.

[0095] Multiple components in electronic device 10 are connected to input / output (I / O) interface 15, including: input unit 16, such as keyboard, mouse, etc.; output unit 17, such as various types of monitors, speakers, etc.; storage unit 18, such as disk, optical disk, etc.; and communication unit 19, such as network card, modem, wireless transceiver, etc. Communication unit 19 allows electronic device 10 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0096] Processor 11 can be a variety of general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of processor 11 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various processors running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Processor 11 performs the various methods and processes described above, such as a photopolymerization printing method.

[0097] In some embodiments, a photopolymer printing method may be implemented as a computer program tangibly contained in a computer-readable storage medium, such as storage unit 18. In some embodiments, part or all of the computer program may be loaded and / or mounted on electronic device 10 via read-only memory (ROM) 12 and / or communication unit 19. When the computer program is loaded into random access memory (RAM) 13 and executed by processor 11, one or more steps of the photopolymer printing method described above may be performed. Alternatively, in other embodiments, processor 11 may be configured to perform a photopolymer printing method by any other suitable means (e.g., by means of firmware).

[0098] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), system-on-a-chip (SoCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transferring data and instructions to the storage system, the at least one input device, and the at least one output device.

[0099] A computer program for implementing a photopolymerization printing method of the present invention can be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the processor, the computer program causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The computer program can be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0100] This invention also provides a computer-readable storage medium storing computer instructions for causing a processor to execute a photopolymerization printing method, the method comprising: Obtain the 3D digital model to be printed, slice the 3D digital model to obtain multiple model slices; Obtain the photopolymerization molding working curve and exposure parameters; determine the number of redundant curing layers based on the photopolymerization molding working curve and exposure parameters; For the current model layer, the current model layer is divided into regions based on the cured model layers that match the number of redundant cured layers, resulting in multiple forming regions. Based on the multiple forming regions and the number of redundant cured layers, multiple progressive mask images corresponding to the current model layer are determined, and the thickness information of the cured model is obtained. Based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model layer, and the exposure parameters, the first exposure time corresponding to each of the multiple forming regions is determined. Based on the first exposure time corresponding to each of the multiple forming regions, the second exposure time corresponding to each of the multiple progressive mask images is determined. Based on the second exposure time and the exposure parameters, the multiple progressive mask images are sequentially exposed and printed to obtain the photopolymerized solid model of the current model layer. After exposing and printing each layer of the model layer by layer, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained.

[0101] In the context of this invention, a computer-readable storage medium can be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus, or device. A computer-readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. Alternatively, a computer-readable storage medium may be a machine-readable signal medium. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0102] To provide interaction with a user, the systems and techniques described herein can be implemented on an electronic device having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the electronic device. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0103] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as data servers), or middleware components (e.g., application servers), or frontend components (e.g., user computers with graphical user interfaces or web browsers through which users can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., communication networks). Examples of communication networks include local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

[0104] A computing system can include clients and servers. Clients and servers are generally located far apart and typically interact through a communication network. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or cloud host, which is a hosting product within the cloud computing service system to address the shortcomings of traditional physical hosts and VPS services, such as high management difficulty and weak business scalability.

[0105] This invention also provides a computer program product, including a computer program that, when executed by a processor, implements a photopolymerization printing method according to any embodiment of the invention.

[0106] In implementing the computer program product, computer program code for performing the operations of this invention can be written in one or more programming languages ​​or a combination thereof. Programming languages ​​include object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0107] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0108] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A photopolymerization printing method, characterized in that, include: Obtain the 3D digital model to be printed, slice the 3D digital model to obtain multiple model slices; Obtain the working curve and exposure parameters of photopolymerization molding; The number of excess curing layers is determined based on the photopolymerization molding working curve and the exposure parameters; For the current model cut layer, the current model cut layer is divided into regions based on the cured model cut layers that match the number of redundant cured layers, resulting in multiple forming regions; Based on the multiple forming regions and the number of redundant solidification layers, determine multiple progressive mask images corresponding to the current model cutting layer; Obtain the thickness information of the cured model, and determine the first exposure time corresponding to each of the multiple molding areas based on the photopolymerization molding working curve, the thickness information of the cured model, the expected printing thickness of the current model layer, and the exposure parameters; The second exposure time corresponding to the multiple progressive mask images is determined based on the first exposure time corresponding to the multiple forming regions; Based on the second exposure duration and the exposure parameters, the plurality of progressive mask images are sequentially exposed and printed to obtain the photocurable solid model of the current model slice layer; After exposing and printing each layer of the multiple model slices, a three-dimensional solid model corresponding to the three-dimensional digital model is obtained.

2. The method according to claim 1, characterized in that, The cured model thickness information includes the cured model thickness information corresponding to the multiple molding areas respectively; the exposure parameters include light intensity; Based on the photopolymerization molding working curve, the cured model thickness information, the expected printing thickness of the current model layer, and the exposure parameters, the first exposure time corresponding to each of the multiple molding areas is determined, including: Based on the light intensity and the desired printing thickness, the critical exposure energy and material penetration depth information are determined by matching them in the photopolymerization working curve. The effective penetration depth of each of the multiple molding areas is determined based on the material penetration depth information and the solidified model thickness information corresponding to the multiple molding areas. The safe exposure energy threshold is determined based on the effective penetration depth and the critical exposure energy. The first exposure duration is determined based on the safe exposure energy threshold and the light intensity.

3. The method according to claim 2, characterized in that, The plurality of molding regions include solid regions and at least one multi-level redundant cured regions; After obtaining the photocured solid model of the current model slice, the method further includes: Based on the critical exposure energy, the material penetration depth information, the light intensity, and the first exposure time corresponding to the redundant curing areas in the multiple molding areas, the first incremental curing thickness of the multi-level redundant curing areas in the multiple molding areas is determined; based on the first incremental curing thickness of the multi-level redundant curing areas in the multiple molding areas, the cured model thickness information is updated to obtain the updated cured model thickness information; or, Based on the critical exposure energy, the material penetration depth information, the light intensity, and the second exposure time corresponding to the multiple progressive mask images, the second incremental curing thickness corresponding to each of the multiple progressive mask images is determined; based on the second incremental curing thickness corresponding to each of the multiple progressive mask images, the cured model thickness information is updated to obtain the updated cured model thickness information.

4. The method according to claim 2, characterized in that, The exposure parameters also include the expected exposure time for the solid areas corresponding to the multiple molding areas; Determining the number of excess curing layers based on the photopolymerization molding working curve and the exposure parameters includes: The exposure curing depth is determined based on the photocuring working curve, the light intensity, and the desired exposure time. The number of redundant curing layers is determined based on the exposure curing depth and the expected printing thickness of the current model cut layer.

5. The method according to claim 1, characterized in that, The plurality of molding regions include solid regions and at least one multi-level redundant cured regions; Based on the multiple forming regions and the number of redundant solidification layers, multiple progressive mask images corresponding to the current model cutting layer are determined, including: Based on the number of redundant curing layers, the plurality of forming areas are masked to obtain a solid mask area and a multi-level redundant curing mask area. The solid mask area is the light transmission range corresponding to the solid area, and the multi-level redundant curing mask area is the light transmission range of the at least one multi-level redundant curing area. Using the physical mask area as the light-transmitting base area, multi-level redundant solidified mask areas of different levels are sequentially superimposed in order of decreasing layer number. Each superimposed multi-level redundant solidified mask area results in a set of superimposed light-transmitting areas. Based on the physical mask region and the superimposed light-transmitting region, a physical mask image and a superimposed light-transmitting mask image are generated respectively; Based on the physical mask image and the superimposed transparent mask image, multiple progressive mask images corresponding to the current model slice layer are determined.

6. The method according to claim 5, characterized in that, Determining the second exposure time corresponding to each of the multiple progressive mask images based on the first exposure time corresponding to each of the multiple forming regions includes: For the entity mask image, the expected exposure time of the entity region is obtained; based on the expected exposure time and the first exposure time of the first superimposed transparent region, the second exposure time of the entity mask image is determined; For the current superimposed light transmittance mask, obtain the first exposure time of the current superimposed light transmittance mask and the first exposure time of the next level of superimposed light transmittance masks; determine the second exposure time corresponding to the current superimposed light transmittance mask based on the difference between the first exposure time of the current superimposed light transmittance mask and the first exposure time of the next level of superimposed light transmittance masks; Wherein, the sum of the second exposure duration of the physical mask image and the second exposure duration of the plurality of superimposed transparent masks is the expected exposure duration of the physical mask image.

7. The method according to claim 1, characterized in that, The plurality of molding regions include solid regions and at least one multi-level redundant cured regions; Based on the number of cured model layers that match the excess cured layers, the current model layer is divided into regions to obtain multiple forming regions, including: Based on the current model cut layer, trace back the already cured model cut layers that match the number of redundant cured layers; Identify the redundant cured areas in adjacent cut layers of the cured model; Based on the current model cut layer and the previous model cut layer, determine the redundant solidified area of ​​the current model cut layer; The redundant solidified regions of adjacent cut layers in the solidified model are projected onto the current model cut layer to obtain the solidified projected region; based on the solidified projected region and the redundant solidified region of the current model cut layer, the multi-level redundant solidified regions corresponding to the current model cut layer are determined; Based on the multi-level redundant solidified regions, the current model layer is divided into regions to obtain the solid region and the multi-level redundant solidified regions.

8. A photopolymerization printing apparatus, characterized in that, include: The model slicing layer determination module is used to obtain the 3D digital model to be printed, slice the 3D digital model, and obtain multiple model slices. The module for determining the number of redundant curing layers is used to obtain the working curve and exposure parameters of photocuring molding. The number of excess curing layers is determined based on the photopolymerization molding working curve and the exposure parameters; The photopolymer solid model printing module is used to divide the current model layer into regions based on the already cured model layers with the excess number of cured layers, thereby obtaining multiple forming regions. Based on the multiple forming regions and the number of redundant curing layers, determine multiple progressive mask images corresponding to the current model cutting layer, obtain the thickness information of the cured model, and determine the first exposure time corresponding to the multiple forming regions based on the photocuring molding working curve, the thickness information of the cured model, the expected printing thickness of the current model cutting layer, and the exposure parameters. The second exposure time corresponding to the multiple progressive mask images is determined based on the first exposure time corresponding to the multiple forming regions; Based on the second exposure duration and the exposure parameters, the plurality of progressive mask images are sequentially exposed and printed to obtain the photocurable solid model of the current model slice layer; The 3D solid model determination module is used to obtain the 3D solid model corresponding to the 3D digital model by performing layer-by-layer exposure printing on the multiple model slices.

9. An electronic device, characterized in that, The electronic device includes: At least one processor; and A memory communicatively connected to the at least one processor; wherein, The memory stores a computer program that can be executed by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the photopolymerization printing method according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the photopolymerization printing method according to any one of claims 1-7.

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