Method and system for volumetric bioprinting

Abstract

The application relates to a volumetric bio-printing method and a printing system, and relates to the technical field of additive manufacturing. The volumetric bio-printing method comprises the following steps: constructing a biological coordinate point in printing glue in a material bottle based on a three-dimensional target model to be printed, and injecting a biological building unit into the biological coordinate point in the printing glue; outputting a corresponding projection pattern at each predetermined angle based on the three-dimensional target model to be printed, and modulating a solidification laser into a dynamic pattern laser based on the projection pattern; projecting the dynamic pattern laser to the material bottle along a first direction, the material bottle is controlled to rotate at a constant speed along an axis of the material bottle, and the printing glue is exposed to the dynamic pattern laser to generate a printing product; acquiring a product image of the printing product in real time, extracting an image feature of the product image, and analyzing and comparing the image feature with the three-dimensional target model. The application can realize accurate positioning of the biological building unit, avoid cell waste, improve the forming precision and consistency of the printing product, and improve the forming precision and success rate of the printing product.

Description

Technical Field

[0001] This application relates to the field of additive manufacturing technology, and in particular to a volumetric bioprinting method and printing system. Background Technology

[0002] Volumetric bio-3D printing places bio-ink in a transparent container and uses projected light patterns to illuminate it from different angles, allowing the light dose to accumulate and solidify in three-dimensional space, thereby achieving the rapid construction of three-dimensional objects without contact or layering.

[0003] In related technologies, volumetric bio-3D printing often employs open-loop printing, making it impossible to ascertain the actual morphology, degree of curing, and deviation from the design model of the cured portion during the printing process. This makes it difficult to make timely adjustments should any abnormalities occur. Furthermore, the container holding the photosensitive bio-ink can only rotate around a single axis, resulting in poor relative pose adjustment between the cured projected pattern and the printing adhesive. Summary of the Invention

[0004] Therefore, it is necessary to provide a new volumetric bioprinting method and system to address the problems of the inability to adjust deviations in a timely manner and the poor relative pose adjustment capability between the solidified projection pattern and the printing adhesive.

[0005] To achieve the above objectives, the technical solution adopted in this application is as follows:

[0006] In a first aspect, embodiments of this application provide a volumetric bioprinting method, comprising:

[0007] Based on the three-dimensional target model to be printed, biological coordinate points are constructed in the printing adhesive inside the material bottle, and biological building blocks are injected into the biological coordinate points.

[0008] Based on the three-dimensional target model to be printed, output the corresponding projection pattern at each predetermined angle, and modulate the curing laser into a dynamic pattern laser based on the projection pattern;

[0009] The dynamic pattern laser is projected onto the material bottle along a first direction. The material bottle and the dynamic pattern laser are rotated relative to each other in a controlled manner. The printing adhesive is exposed by the dynamic pattern laser to generate a printed product.

[0010] The product image of the printed product is acquired in real time, the image features of the product image are extracted, and the image features are analyzed and compared with the three-dimensional target model.

[0011] If the image feature deviates from the expected image of the three-dimensional target model, adjust the relative position of the material bottle or adjust the focal plane of the dynamic pattern laser; if the grayscale value of the image feature deviates from the set grayscale value of the three-dimensional target model, adjust the power of the curing laser and / or the exposure time of the printing adhesive.

[0012] In one embodiment of the first aspect, the controlled curing laser is modulated into a dynamic pattern laser based on the projected pattern, comprising:

[0013] Emitting a curing laser;

[0014] The diameter of the curing laser is increased and the curing laser is collimated to obtain a shaped beam;

[0015] The projection beam is obtained by modulating the shaping beam based on the projection pattern;

[0016] The zero-order light in the projected beam is eliminated to obtain the dynamic pattern laser.

[0017] In one embodiment of the first aspect, the real-time acquisition of the product image of the printed product includes:

[0018] An imaging laser is emitted toward the material bottle along a second direction;

[0019] The diameter of the imaging laser is increased and the imaging laser is collimated to obtain a parallel beam;

[0020] The parallel light beam penetrates the printed product inside the material bottle to form the product image, and the camera is located on one side of the material bottle to receive the product image.

[0021] In one embodiment of the first aspect, extracting image features from the product image includes:

[0022] An image of the product is captured at set angles, and the outline of the solidified area of ​​the current printed product, the gray value, and the projection error between the current printed product and the three-dimensional target model at the current angle are calculated in real time.

[0023] In one embodiment of the first aspect, adjusting the relative position of the material bottles includes:

[0024] If the outline of the solidified area of ​​the printed product is offset relative to the three-dimensional target model in the second direction, the material bottle is driven to perform displacement compensation along the second direction.

[0025] If the outline of the solidified area of ​​the printed product is asymmetrical or there is a projection error between the current printed product and the three-dimensional target model at the current angle, the material bottle is driven to swing in an arc around the first axis and / or around the second axis.

[0026] The first axis is parallel to the first direction, the second axis is parallel to the second direction, and there is an angle between the first direction and the second direction.

[0027] In one embodiment of the first aspect, adjusting the focal plane of the dynamic pattern laser includes:

[0028] If the outline of the cured area of ​​the printed product is offset relative to the three-dimensional target model in the first direction, the position of the focal plane of the dynamic pattern laser in the first direction is adjusted. In one embodiment of the first aspect, adjusting the power of the curing laser and / or the exposure time of the printing adhesive includes:

[0029] If the grayscale value of the image feature is lower than the set grayscale value of the three-dimensional target model, then increase the power of the curing laser at subsequent angles or extend the exposure time of the printing adhesive.

[0030] If the grayscale value of the image feature is higher than the set grayscale value of the three-dimensional target model, then the power of the curing laser at subsequent angles is reduced or the exposure time of the printing adhesive is shortened.

[0031] In one embodiment of the first aspect, the volumetric bioprinting method further includes:

[0032] After printing is completed, the printed product is subjected to a full-cycle inspection, and a quality report is generated.

[0033] In one embodiment of the first aspect, the volumetric bioprinting method further includes:

[0034] A matching liquid tank is provided on the outer periphery of the material bottle, and there is a gap between the matching liquid tank and the material bottle, and the space between the matching liquid tank and the material bottle is filled with matching liquid;

[0035] The refractive index difference between any two of the following: the wall of the matching liquid tank, the matching liquid, the body of the material bottle, and the printing adhesive is 0-0.05.

[0036] Secondly, embodiments of this application also provide a printing system applied to the volumetric bioprinting method described in any of the above embodiments, the printing system comprising:

[0037] An adjustment module is used to place the material bottle and adjust its relative position in multiple degrees of freedom;

[0038] The curing module is capable of emitting the curing laser;

[0039] The monitoring module is used to acquire images of the product in real time;

[0040] The control module is capable of setting the projection pattern based on the three-dimensional target model to be printed, and controlling the curing module to modulate the curing laser into the dynamic pattern laser based on the projection pattern; the control module is capable of adjusting the relative position of the material bottle or adjusting the focal plane of the dynamic pattern laser based on the positional deviation between the image features and the expected image of the three-dimensional target model; the control module is also capable of adjusting the power of the curing laser and / or the exposure time of the printing adhesive based on the deviation between the grayscale value of the image features and the grayscale value set by the three-dimensional target model.

[0041] Compared to related technologies, the beneficial effects of this application are as follows: This application provides a volumetric bioprinting method and system. By acquiring product images of the printed product in real time, extracting image features from the product images, and analyzing and comparing the image features with a three-dimensional target model, a closed-loop feedback path of "monitoring-analysis-control" is established. This allows for real-time compensation for pose deviations caused by various factors during the printing process, or adjustment of the curing laser power and the exposure time of the printing adhesive, significantly improving the forming accuracy and consistency of the printed product, and increasing the forming precision and success rate of the printed product. In addition, this application also uses an injection method to inject biological building blocks into biological coordinate points within the printing adhesive, achieving precise positioning of the biological building blocks and avoiding cell waste. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating the volumetric bioprinting method in some embodiments of this application.

[0044] Figure 2 This is a schematic diagram of the printing system in some embodiments of this application;

[0045] Figure 3 This is a schematic diagram of the structure of the adjustment module in some embodiments of this application;

[0046] Figure 4 This is a schematic diagram of the structure of the solidification module and the monitoring module in some embodiments of this application.

[0047] Explanation of reference numerals in the attached figures:

[0048] 100. Printing system; 110. Adjustment module; 111. Rotary stage; 1111. Base; 112. First arc stage; 113. Second arc stage; 114. Translation stage; 120. Curing module; 121. Curing laser; 122. First shaping unit; 123. Modulation unit; 124. Projection lens; 130. Control module; 140. Monitoring module; 141. Imaging laser; 142. Second shaping unit; 143. Camera; 150. Injection module; 160. Matching liquid tank;

[0049] 200, Curing laser; 300, Shaping beam; 400, Dynamic pattern laser; 500, Imaging laser; 600, Parallel beam. Detailed Implementation

[0050] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0051] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0052] Furthermore, where the term "and / or" appears, "and / or" merely describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship. Where the terms "first" and "second" appear, these terms are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" can explicitly or implicitly include at least one of those features. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0053] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0054] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0055] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0056] See Figure 1 As shown, an embodiment of this application provides a volumetric bioprinting method, which includes:

[0057] S10: Based on the three-dimensional target model to be printed, construct biological coordinate points in the printing adhesive inside the material bottle, and inject biological building blocks into the biological coordinate points.

[0058] Specifically, step S10 includes: S11, material introduction.

[0059] For example, this step is mainly used to introduce material bottles, printing adhesive, etc., into the printing system. It should be noted that the introduction step is not limited to the method in which the printing adhesive or material bottle is introduced. In some embodiments, the operator may first inject acellular printing adhesive containing a photoinitiator into the material bottle, and then fix the material bottle on the rotary table 111. In other embodiments, the operator may first fix the material bottle on the rotary table 111, and then inject acellular printing adhesive containing a photoinitiator into the material bottle.

[0060] S12, Material Bottle Calibration.

[0061] For example, this step is used to adjust the position of the material bottle. The printing system acquires the position information of the material bottle, transmits this information to the control module for parsing and judgment, and finally sends it to the adjustment module in the form of control commands. By adjusting the movement of the adjustment module in different degrees of freedom, the material bottle is brought to a preset state (such as a completely vertical state), thus completing the calibration step.

[0062] S13, biological building block injection.

[0063] For example, after the material bottle is calibrated, the printing system can construct bio-coordinate points within the printing adhesive for injecting biological constructs based on the three-dimensional target model to be printed. During injection, the injection module 150 and the material bottle achieve full coverage of the biological coordinate points through relative movement, and the biological constructs are injected into the preset biological coordinate points within the printing adhesive via the injection module 150.

[0064] In some embodiments, the material bottle is stationary, and the injection module 150 (or a portion thereof) moves relative to the material bottle to fully cover the biological coordinate points and complete the injection in a traversal manner. In other embodiments, the injection module 150 (or a portion thereof) is stationary, and the material bottle moves relative to the injection module, similarly covering the biological coordinate points and completing the injection in a traversal manner. In still other embodiments, the injection module 150 (or a portion thereof) and the material bottle move simultaneously along a predetermined trajectory, fully covering the biological coordinate points to complete the injection.

[0065] In this application, it is preferable to achieve full coverage by having the injection module 150 move synchronously with the material bottle.

[0066] For example, the material bottle is controlled to rotate around a vertical axis, and the injection module 150, through multiple degrees of freedom adjustment, injects the biological construct unit into the corresponding biological coordinate point. During the injection process, the system continuously monitors whether the material bottle remains vertical and does not sway left or right during rotation to ensure accurate injection of cell suspensions or organoids.

[0067] It should be noted that the biological building blocks can be cell suspensions or organoids. Specifically, a cell suspension is a mixed system formed by uniformly dispersing single cells or cell populations in a liquid medium, maintaining cell viability and facilitating experimental or therapeutic operations. Cell suspensions can be used to study cell proliferation, differentiation, and apoptosis mechanisms, as well as for drug screening and toxicity assessment. Simultaneously, in the field of regenerative medicine, cell suspensions can be combined with biomaterials to construct artificial tissues or organs, ensuring uniform cell distribution and facilitating quantitative manipulation. Organoids are miniature organ models formed by three-dimensional in vitro culture of stem cells or tissue cells, capable of simulating real organs in structure and function, and are important tools for drug development, disease research, and regenerative medicine.

[0068] S14, matching liquid tank placement.

[0069] For example, a matching liquid tank 160 is mounted around the outside of the material bottle, and matching liquid is injected into the matching liquid tank 160 until the liquid level covers the printing area. At the same time, the refractive indices of the tank wall of the matching liquid tank 160, the matching liquid, the material bottle, and the printing adhesive are similar, which minimizes the deflection of the curing light and effectively eliminates the lens effect and optical distortion caused by the curved surface of the material bottle.

[0070] S20, based on the three-dimensional target model to be printed, outputs the corresponding projection pattern at each predetermined angle, and modulates the curing laser 200 into a dynamic pattern laser 400 based on the projection pattern.

[0071] Specifically, step S20 includes: S21, slice acquisition.

[0072] It should be noted that, for ease of understanding, the coordinates in this application embodiment are illustrated using Cartesian coordinates. Of course, other coordinate systems may be used in some implementations, and no specific limitation is made here. In this application embodiment, the first direction is parallel to the y-axis, the second direction is parallel to the x-axis, and the third direction is parallel to the z-axis.

[0073] For example, this step is used to obtain a solidified projection pattern of a three-dimensional target model. The system decomposes the three-dimensional target model into N angles around the z-axis according to preset requirements, and generates slice patterns of the three-dimensional target model at the corresponding positions of the above N angles according to the tomography principle of volumetric printing.

[0074] Understandably, the number of slices in a 3D target model is influenced by at least the model's complexity and the modulator's refresh rate, and should be chosen appropriately based on the specific circumstances. Higher model complexity necessitates reducing the angular spacing between adjacent slices and increasing the total number of slices to obtain more precise slice patterns and minimize deviations between the 3D target model and the printed product. Similarly, a higher modulator refresh rate generates more slice patterns, enabling the modulator to quickly convert the slice patterns into a solidified projection pattern, thus ensuring the system's printing efficiency.

[0075] Optionally, in this embodiment, the angular interval between two adjacent slices is 0.5°-2.4°, meaning that the 3D target model generates a slice pattern with the corresponding angle every 0.5°-2.4° rotation, facilitating the subsequent generation of a solidified projection pattern corresponding to the slice pattern. In one specific embodiment, with a rotation cycle of 360°, when a slice image is acquired every 0.5°, the 3D target model will generate 720 slice angles. It should also be noted that the angular interval between adjacent slices can be the same or different.

[0076] S22, Dynamic Pattern Laser Generation.

[0077] For example, the modulator employs a reverse computation strategy based on tomographic imaging principles to transform the three-dimensional target model into a two-dimensional projection sequence for volumetric photopolymerization. Its core lies in simulating the energy accumulation process of light in a rotating medium to determine the required light intensity distribution pattern at each projection angle, and then calculating the corresponding solidified projection pattern from the sliced ​​pattern. The algorithm used by the modulator may include Radon transform, forward projection algorithm, or other reconstruction algorithms suitable for volumetric photopolymerization.

[0078] S23, solidified beam shaping.

[0079] For example, the system expands and collimates the curing laser 200 to form a parallel beam with a large beam diameter and uniform energy, namely the shaping beam 300, to ensure coverage of the entire projection area. Then, during the printing process, the modulator spatially modulates the shaping beam 300 according to the generated curing projection pattern, transforming the shaping beam 300 into a dynamic pattern laser 400 corresponding to the curing projection pattern. Finally, the dynamic pattern laser 400 undergoes zero-order light cancellation and is precisely projected onto the target area inside the material bottle along a set direction.

[0080] S30, the dynamic pattern laser 400 is projected onto the material bottle along a set direction, and the material bottle and the dynamic pattern laser 400 are rotated relative to each other in a controlled manner, and the printing adhesive is exposed by the dynamic pattern laser 400 to generate the printed product.

[0081] In this step, in some embodiments, the dynamic pattern laser 400 is directly incident on the material bottle along a fixed direction, so that the printing adhesive inside the material bottle is exposed by the dynamic pattern laser 400 to generate a printed product. During the printing process, the material bottle is controlled to rotate along its own axis. At the same time, the system refreshes the dynamic pattern laser 400 at the corresponding angle in real time according to the rotation angle of the material bottle. After eliminating zero-order light, the dynamic pattern laser 400 is accurately projected onto the target area inside the rotating material bottle.

[0082] In other embodiments, the material bottle remains fixed, and the dynamic pattern laser 400 can rotate around the circumference of the material bottle. The system refreshes the dynamic pattern laser 400 at the corresponding angle in real time according to the rotation angle of the dynamic pattern laser 400, and the dynamic pattern laser 400 after eliminating zero-order light is accurately projected onto the target area inside the rotating material bottle.

[0083] S40 acquires real-time images of the printed product, extracts image features from the product images, and analyzes and compares the image features with the 3D target model.

[0084] Specifically, step S40 includes: S41, acquiring product images.

[0085] For example, this step is used to acquire real-time image information of the product during the printing process. This application does not limit the method of image acquisition. In one embodiment, this application provides a monitoring module that can provide an imaging laser 500. The imaging laser 500 continuously irradiates the printed product, obtaining transmitted light, scattered light, and reflected light respectively. This application preferably utilizes transmitted light. Furthermore, this embodiment also includes a light receiving device, which can be a photoelectric sensor, an APD (Avalanche Photon Diode), a CCD (Charge Coupled Device), a CMOS (Complementary Metal-Oxide-Semiconductor), etc.

[0086] S42, shaping beam collimation.

[0087] For example, the system expands and collimates the imaging laser 500 to form a parallel beam 600 with a large beam diameter and uniform energy. The parallel beam 600 penetrates the printed product inside the material bottle to form a product image.

[0088] S43. Image information comparison.

[0089] For example, during the printing process, the imaging laser 500 continuously projects onto the material bottle to form a perspective image of the printed product, and the camera 143 continuously captures the transmission images of the printing process. Each time the material bottle rotates by a set angle, the image processing unit of the camera 143 automatically acquires an image of the product. Optionally, the set angle in this step can be 15°-60°.

[0090] An imaging laser is directed along a second direction x, intersecting the first direction y, towards the material bottle to form a perspective image of the printed product from the current viewpoint. The image processing unit of camera 143 can calculate in real time the outline of the solidified area of ​​the printed product, the grayscale value, and the projection error between the printed product and the 3D target model at the current angle. Each frame of the image is analyzed in real time to extract the outline of the forming printed product and compare it with the theoretical outline of the 3D target model at the current rotation angle to determine whether there is a deviation between the printed product and the 3D target model.

[0091] Understandably, the overlap between the perspective image of the printed product and the projected image of the 3D target model from the current viewpoint can be confirmed using the intersection-over-union (IoU) ratio. The IoU value ranges from 0 to 1; a higher value indicates better overlap and higher printing accuracy. When there is a deviation in the overlap between the printed product and the 3D target model, the size of the printed product can be further calculated using an algorithm and compared with the 3D target model. Understandably, the pixel unit size of the camera is fixed; the length of the perspective image = number of pixels * pixel side length. The length of the perspective image is then compared with the 3D target model. If there is a difference between the length of the perspective image and the size of the 3D target model, the laser intensity and exposure time of the curing laser are adjusted accordingly.

[0092] It should be noted that the wavelength range of the imaging laser differs from that of the curing laser. The photoinitiator within the printing adhesive can only be activated by a beam within the wavelength range of the curing laser, thereby generating active free radicals, initiating a polymerization reaction, and transforming the liquid printing adhesive into a solid state.

[0093] Optionally, the wavelength of the curing laser is 365nm to 405nm, and the wavelength range of the imaging laser is 488nm to 633nm.

[0094] S50, if there is a positional deviation between the image features and the expected image of the 3D target model, adjust the relative position of the material bottle, or adjust the focal plane of the dynamic pattern laser 400; if there is a deviation between the grayscale value of the image features and the set grayscale value of the 3D target model, adjust the power of the curing laser 200 and / or the exposure time of the printing adhesive.

[0095] For example, after acquiring the image, the system enters the crucial feedback control stage. Based on the real-time acquired product image, subsequent logical judgments and operations are executed. Specifically, the system compares the current product image with the expected image of the 3D target model and determines whether there is a positional deviation or a grayscale value deviation.

[0096] Taking the Cartesian coordinates in the above embodiment as an example, the dynamic pattern laser 400 is directed towards the material bottle along the y-axis, the imaging laser 500 is directed towards the material bottle along the x-axis, and the material bottle is controlled to rotate around the z-axis.

[0097] If the outline of the cured area of ​​the printed product is offset relative to the 3D target model in the x-axis direction, the material bottle is driven to perform displacement compensation along the x-axis direction. This movement of the material bottle aligns the dynamic pattern laser 400 with the material bottle in the x-axis direction. Conversely, if the outline of the cured area of ​​the printed product is offset relative to the 3D target model in the y-axis direction, since the irradiation direction of the dynamic pattern laser 400 is parallel to the y-axis direction, the focal point of the dynamic pattern laser 400 can be adjusted to position the focal plane at the material bottle in the y-axis direction, ensuring printing accuracy.

[0098] If the grayscale value of the image feature is lower than the set grayscale value of the 3D target model, it indicates that the light energy density received by that pixel is low, and there is a risk of under-curing of the printing adhesive, leading to problems such as holes, layer separation, and support breakage in the model. To address this, the power of the curing laser 200 at subsequent angles can be increased or the exposure time of the printing adhesive can be extended to improve the curing degree of the printing adhesive.

[0099] If the grayscale value of the image feature is higher than the set grayscale value of the 3D target model, it indicates that the light energy density received by the current pixel is high, and there is a risk of over-curing of the printing adhesive, curing deeper layers of printing adhesive that should not be cured, resulting in blurred details and swelling. To address this, the power of the curing laser 200 at subsequent angles can be reduced or the exposure time of the printing adhesive can be shortened.

[0100] S60: After printing is completed, a full-cycle inspection of the printed product is performed, and a quality report is generated.

[0101] For example, after printing is completed, an imaging laser 500 is again directed at the printed product along the x-axis. The printed product and the material bottle are controlled to rotate around the z-axis. Camera 143 acquires a full-circle image of the printed product. An image recognition algorithm is used to analyze the acquired surface image to determine whether the printed product has defects. After inspection, the system automatically generates a quality report, which includes, but is not limited to, the following information:

[0102] Inspection identification information, such as the name of the printing task, printing time, batch of materials used, and version of the parameters used for testing.

[0103] Based on the pre-set pass / fail criteria, the final judgment is given as "pass", "fail", or "requires manual re-inspection".

[0104] If the test fails, the report will also provide preliminary suggestions based on the type of defect, such as "suggest adjusting the exposure time", "suggest adjusting the intensity of the curing laser by 200", or "suggest calibrating the x-axis accuracy".

[0105] See Figure 2 and Figure 3 As shown, another objective of this application is to provide a printing system 100 for volumetric bio-3D printing of in vitro tissues and organoids. The printing system 100 includes an adjustment module 110, a curing module 120, a control module 130, and a monitoring module 140.

[0106] The adjustment module 110 is used to adjust the position of the material bottle in multiple degrees of freedom, and the material bottle stores printing adhesive. The curing module 120 can emit a curing laser 200 to achieve cross-linking and curing of the printing adhesive; the monitoring module 140 is communicatively connected to the control module 130, providing real-time product images of the printing adhesive so that the control module 130 can generate instructions to control the position of the material bottle; the adjustment module 110 is connected to the control module 130 to receive the instructions and adjust the position of the material bottle.

[0107] During printing, the control module generates a projection pattern based on the three-dimensional target model to be printed, and the curing module 120 modulates the curing laser 200 into a dynamic pattern laser 400 based on the projection pattern and irradiates the printing adhesive, finally curing to obtain a printed product corresponding to the three-dimensional target model.

[0108] For example, the material bottle is a transparent container, allowing the laser to penetrate and interact with the printing adhesive inside. Optionally, the material bottle can be made of materials such as transparent quartz glass, polypropylene, or polyethylene terephthalate. The shape of the material bottle is not limited in this application and can be a square prism, cylinder, frustum, etc., preferably cylindrical, with an inner diameter of 10-20 mm and a wall thickness of 0.8-1.2 mm. In one specific embodiment, the material bottle has an inner diameter of 16.5 mm and a wall thickness of 1 mm, achieving optimal laser irradiation. To facilitate the introduction of printing adhesive, it is further preferred that the material bottle has a closed bottom and an opening at the top.

[0109] Printing adhesive and bio-building units are introduced into the material bottle respectively. The printing adhesive undergoes a cross-linking reaction under light of a specific wavelength, solidifying from a liquid state to a gel state, thereby achieving three-dimensional structure formation. The printing adhesive consists of a hydrogel precursor and a photoinitiator. The hydrogel precursor can be any one or a combination of GelMA (Gelatin Methacryloyl) and diphenylazidophosphate, and the photoinitiator can be any one or a combination of LAP (Lithium(2,4,6-trimethylbenzoyl)phosphate). In this application, the absorption peak of the photoinitiator is 405 nm.

[0110] The biological building blocks can be cell suspensions or pre-formed organoids. When the biological building blocks are cell suspensions, the cell suspension concentration can be 10. 6 -10 7 cells / mL; when the biological building block is an organoid, the diameter of the organoid can be 50μm-500μm.

[0111] To address the shortcomings of existing open-loop printing systems that cannot be adjusted in a timely manner, this application includes an adjustment module 110. This module adjusts the relative position of the material bottle in multiple degrees of freedom, enabling translation, rotation, tilting, or combinations of these actions to ensure that the dynamic pattern laser 400 accurately targets the printing adhesive. Optionally, the adjustment module 110 can be a four-axis automatic motion platform. The adjustment module 110 dynamically adjusts the position and orientation of the material bottle, compensating for potential mechanical errors and alignment deviations in the system, and enabling more complex printing strategies. This ensures that the laser emitted from the curing module 120 is precisely projected onto the target area within the printing adhesive, thus providing positional assurance for high-precision printing.

[0112] The curing module 120 emits a curing laser 200 and, according to instructions from the control module 130, modulates the laser into a dynamic pattern laser 400. The dynamic pattern laser 400 is a laser beam whose intensity presents a specific two-dimensional pattern in space, and the pattern can change over time. This pattern sequence is derived from a three-dimensional target model and is used to accumulate light dose within the printing adhesive to form a three-dimensional structure.

[0113] In this way, the three-dimensional digital model is transformed into a series of two-dimensional optical patterns. By projecting these patterns at different times and angles, light dose is accumulated in the printing adhesive inside the material bottle. When the accumulated light dose at a specific location reaches the curing threshold, the printing adhesive at that location will cure, thus realizing the transformation from a digital model to a physical entity.

[0114] The control module 130 is electrically connected to the adjustment module 110 and the curing module 120 for data transmission. The control module 130 can send corresponding control commands to the adjustment module 110 and the curing module 120 according to an algorithm, and is responsible for the coordinated operation of the entire printing process. First, based on the three-dimensional target model to be printed, the control module 130 calculates and sets a series of projection patterns using an algorithm. Then, it controls the curing module 120 to generate and project dynamic pattern lasers 400 according to a predetermined sequence and timing.

[0115] The monitoring module 140 is also electrically connected to the control module 130. Its core function is to acquire images of the printing adhesive in real time during the printing process and transmit the image information to the control module 130. The image refers to the image acquired in real time by the monitoring module 140 that reflects the curing state of the printing adhesive during the printing process.

[0116] Based on the real-time product image acquired by the monitoring module 140, the control module 130 can perform closed-loop feedback control. Specifically, the control module 130 analyzes the product image and compares it with the expected state of the 3D target model at that moment to determine whether there is a positional deviation or grayscale value deviation. Through this closed-loop feedback of "monitoring-comparison-adjustment", the system can proactively and in real-time correct errors in the printing process, thereby greatly improving the accuracy and success rate of the printed products.

[0117] Specifically, if the outline of the cured area of ​​the printed product is offset relative to the 3D target model in the second direction, the material bottle is driven to perform displacement compensation along the second direction. This movement of the material bottle in the second direction aligns the dynamic pattern laser 400 with the material bottle. Conversely, if the outline of the cured area of ​​the printed product is offset relative to the 3D target model in the first direction, since the irradiation direction of the dynamic pattern laser 400 is parallel to the first direction, the focal point of the dynamic pattern laser 400 can be adjusted to position the focal plane at the material bottle in the first direction, ensuring printing accuracy.

[0118] If the grayscale value of the image feature is lower than the set grayscale value of the 3D target model, it indicates that the light energy density received by that pixel is low, and there is a risk of under-curing of the printing adhesive, leading to problems such as holes, layer separation, and support breakage in the model. To address this, the power of the curing laser 200 at subsequent angles can be increased or the exposure time of the printing adhesive can be extended to improve the curing degree of the printing adhesive.

[0119] If the grayscale value of the image feature is higher than the set grayscale value of the 3D target model, it indicates that the light energy density received by the current pixel is high, and there is a risk of over-curing of the printing adhesive, curing deeper layers of printing adhesive that should not be cured, resulting in blurred details and swelling. To address this, the power of the curing laser 200 at subsequent angles can be reduced or the exposure time of the printing adhesive can be shortened.

[0120] Continue reading Figure 3 As shown, in some embodiments, the adjustment module 110 includes a rotary table 111, a first arc swing table 112, and a second arc swing table 113. The rotary table 111, the first arc swing table 112, and the second arc swing table 113 are stacked sequentially along the z-axis. The material bottle is placed on the rotary table 111 and can rotate around the z-axis under the drive of the rotary table 111. The first arc swing table 112 can drive the material bottle to swing around the y-axis in an arc, and the second arc swing table 113 can drive the material bottle to swing around the x-axis in an arc.

[0121] For example, a rotatable base 1111 is provided above the rotary table 111, and the material bottle is placed on the base 1111. The rotary table 111 drives the base 1111 to rotate, thereby causing the material bottle to rotate around the z-axis, so as to ensure that the dynamic pattern laser 400 can be projected onto the printing adhesive from different angles.

[0122] The first arc stage 112 can drive the material bottle to swing in an arc along the y-axis, and the second arc stage 113 can drive the material bottle to swing in an arc along the x-axis. This multi-axis design provides a more powerful attitude adjustment capability compared to the single-axis rotation commonly used in the prior art. By adjusting the settings of the module 110, this application can not only complete basic rotational projection, but also perform precise centering and leveling before printing, and compensate for more complex attitude deviations during printing; it can achieve more precise and comprehensive control over the relative pose between the beam and the printing area, thereby significantly improving the fidelity when printing complex asymmetric structures.

[0123] Specifically, the rotating table 111 has a groove on its surface with a diameter slightly larger than the body of the material bottle for fixing the bottle. The rotating table 111, the first arc swing table 112, and the second arc swing table 113 can all use stepper motors with worm gear reducers to ensure smooth transmission and self-locking. The first arc swing table 112 and the second arc swing table 113 can be limited by setting angle encoders to limit their swing arc.

[0124] Optionally, the swing angle range of the first arc swing stage 112 and the second arc swing stage 113 is ±10°.

[0125] In some embodiments, the adjustment module 110 further includes a translation stage 114, which is disposed on the side of the second arc swing stage 113 away from the first arc swing stage 112. The translation stage 114 can drive the material bottle to move along the x-axis.

[0126] For example, the translation stage 114 is positioned on the side of the second arc-shaped stage 113 opposite to the first arc-shaped stage 112, enabling it to drive the material bottle and the entire rotating and swinging mechanism above it to move linearly along the x-axis. The dynamic pattern laser 400 is directed towards the material bottle along the y-axis. The translation stage 114 can be used to correct the lateral offset of the printing center. If the focus of the dynamic pattern laser 400 is not on the material bottle, the adjustment unit adjusts the focus position of the dynamic pattern laser 400 so that the focal plane is located on the material bottle in the first direction, ensuring printing accuracy.

[0127] Before printing begins, the rotation center of the material bottle can be precisely aligned with the center of the curing beam using the translation stage 114. During printing, if the monitoring module 140 detects overall lateral drift in the printed product, the control module 130 can drive the translation stage 114 for fine-tuning compensation. By increasing this translational degree of freedom, the problem of difficulty in perfectly correcting the center position deviation by relying solely on oscillation is solved, achieving comprehensive control of the material bottle's position through "translation + tilt + rotation," further improving the system's alignment accuracy and robustness.

[0128] Specifically, the translation stage 114 can employ a stepper motor and a linear guide transmission mechanism. Furthermore, the adjustment module 110 also includes a base. The translation stage 114 is made of cast iron or aluminum alloy plate with a surface flatness ≤0.05mm and is equipped with linear guides. After the translation stage 114 is mounted on the base, it sequentially supports the second arc swing stage 113, the first arc swing stage 112, and the rotary stage 111.

[0129] In some embodiments, the printing system 100 further includes a matching liquid tank 160, which is disposed around the periphery of the material bottle and contains matching liquid. The refractive indices of the tank wall of the matching liquid tank 160, the matching liquid, the body of the material bottle, and the printing adhesive are similar, and the difference in refractive indices between any two is 0-0.05.

[0130] For example, the matching liquid tank 160 can be made of transparent acrylic or quartz glass, and is prismatic in shape with a square cavity inside, the inner side length of which is 5mm-10mm larger than the outer diameter of the material bottle. The bottom of the matching liquid tank 160 is sealed and fixed on the rotating table 111, forming a cavity between it and the material bottle, and the cavity is filled with matching liquid. In one embodiment, the matching liquid tank is supported by quartz glass with a refractive index of 1.46, and the refractive index of the printing adhesive is 1.48-1.52. Therefore, the matching liquid can be an aqueous solution of glycerol with a refractive index of 1.47-1.48 or silicone oil with a refractive index of 1.49-1.50, so that the refractive index of the matching liquid is close to that of the quartz glass and the printing adhesive. In some embodiments, the matching liquid can also be the same printing adhesive without photoinitiator. This type of printing adhesive will not cure after being irradiated by a curing laser, and the matching liquid has the same refractive index as the printing adhesive, thus minimizing beam refraction deviation. Thus, when the curing laser 200 passes through the series of interfaces of "air-matching liquid tank wall-matching liquid-material bottle wall-printing adhesive", the refractive index of each medium is very close, the deflection of the light is minimized, effectively eliminating the lens effect and optical distortion caused by the curved surface of the material bottle, ensuring that the dynamic pattern laser 400 can be projected onto the predetermined position with high fidelity, thereby significantly improving the shape accuracy of the printed product.

[0131] In some embodiments, the printing system 100 further includes an injection module 150, which includes a syringe. After the material bottle is filled with printing adhesive, it is placed in the adjustment module 110. The injection module 150 injects the biological building blocks into the printing adhesive at preset coordinates through the syringe.

[0132] For example, the injection module 150 may include a syringe and a three-dimensional micro-motion platform. The syringe is mounted on the three-dimensional micro-motion platform to adjust the working posture under the action of the platform. Specifically, the operation process of the injection module 150 is as follows: First, cell-free printing adhesive is injected into the material bottle and placed on the adjustment module 110. Then, the injection module 150 uses the syringe to precisely inject the cell suspension or pre-formed organoids into the preset three-dimensional coordinate position inside the printing adhesive. After slow injection, the syringe is withdrawn, and the needle path is automatically closed by the flow of printing adhesive. This effectively solves the problem of a large number of cells being wasted in non-target areas due to the pre-mixing of cells with printing adhesive in traditional methods, greatly improving cell utilization, which is especially important when using expensive or rare cells (such as stem cells and primary cells) for research. At the same time, since most of the printing adhesive does not contain cells, light scattering is reduced, making the curing process more uniform and controllable, further improving printing accuracy. It should be noted that during this process, the control module 130 acquires a transmission image of the material bottle through the camera 143, and the software identifies the edge of the bottle wall. The first arc-shaped stage 112 and the second arc-shaped stage 113 rotate automatically, making the left and right edges of the bottle wall parallel and symmetrical in the image.

[0133] Continue reading Figure 4 As shown, in some embodiments, the control module 130 includes a projection generation unit that rotates around the z-axis, decomposing the three-dimensional target model into N angles in a direction surrounding the z-axis. For example, the control unit generates a slice for every 0.5°-2.4° rotation of the material bottle and decomposes it into a projection pattern.

[0134] The curing module 120 includes a curing laser 121, a first shaping unit 122, a modulation unit 123, and a projection lens 124. The curing laser 121 can controllably emit a curing laser 200. The first shaping unit 122 is used to enlarge the diameter of the curing laser 200 and collimate the curing laser 200 to obtain a shaped beam 300. The modulation unit 123 modulates the shaped beam 300 based on the projection pattern to obtain a dynamic pattern laser 400. The projection lens 124 is used to process the dynamic pattern laser 400, eliminate zero-order light, and accurately project it onto the target area inside the material bottle.

[0135] For example, the control module 130 includes an industrial computer and a software control program installed within the industrial computer. The software control program includes a projection generation unit, which can rotate and slice the user-input 3D target model to be printed along the z-axis. Similar to the reverse process of a CT scan, the projection generation unit calculates, based on tomography theory, the 2D projection pattern that needs to be projected at a series of rotation angles in order to finally form a 3D object.

[0136] The first shaping unit 122 can consist of a set of Galilean beam expanders and rectangular adjustable apertures, expanding the laser beam diameter to 5-30 mm, with a parallelism better than 1 mrad after collimation. If necessary, a homogenizing element, such as a compound eye lens, can be added to make the beam energy distribution more uniform.

[0137] The modulation unit 123 employs a reflective digital micromirror device or a liquid crystal spatial light modulator, with a pixel array of 1358×800 or higher and a refresh rate ≥60Hz. The modulation unit 123 is connected to an industrial control computer to receive the projected pattern in real time and generate a dynamic pattern laser 400.

[0138] The projection lens 124 consists of a set of projection lenses 124 to eliminate zero-order light generated during the projection of the dynamic pattern laser 400.

[0139] Specifically, during operation, the curing laser 121 emits a curing laser 200 under the control of the control module 130. This laser beam first passes through a first shaping unit 122, which expands the diameter of the laser beam and makes it uniformly parallel to ensure coverage of the entire projection area. Subsequently, the shaped beam 300 illuminates a modulation unit 123, which receives projection pattern instructions from a projection generation unit and spatially modulates the intensity of the shaped beam 300 to generate the desired dynamic pattern laser 400. Finally, the projection lens 124 eliminates the zero-order light of the dynamic pattern laser 400, allowing it to be precisely projected onto the target area inside the material bottle. This series of optical path designs achieves a precise conversion from digital signals to physical light patterns. During each projection cycle, the control module 130 sends a slice pattern at a corresponding angle to the spatial light modulator to generate the current curing projection pattern. The projection pattern can be calculated using Radon transform, forward projection algorithm, or other reconstruction algorithms suitable for volumetric photopolymerization.

[0140] In some embodiments, the control module 130 further includes a motion control unit, which is used to set a motion trajectory according to the three-dimensional target model.

[0141] For example, the software control program of the control module 130 also includes a motion control unit, which sets the motion trajectory of each motion axis in the adjustment module 110 according to the three-dimensional target model and the preset printing strategy (such as rotation speed, angle increment, etc.) to ensure that when the Nth pattern is projected, the material bottle is rotated to the Nth predetermined angle, thus ensuring the correct accumulation of light dose in three-dimensional space.

[0142] In some embodiments, the monitoring module 140 includes an imaging laser 141, a second shaping unit 142, and a camera 143. The imaging laser 141 can controllably emit an imaging laser 500, which is directed toward the material bottle along the x-axis. The second shaping unit 142 is disposed between the imaging laser 141 and the material bottle. The second shaping unit 142 is used to enlarge the diameter of the imaging laser 500 and collimate the imaging laser 500 to obtain a parallel beam 600. The parallel beam 600 penetrates the printed product inside the material bottle to form a product image. The camera 143 is located on the side of the material bottle away from the imaging laser 141 to receive the product image.

[0143] For example, to achieve uninterrupted monitoring of the printing process, the imaging laser 500 emitted by the imaging laser 141 has a different wavelength than the curing laser 200, and a wavelength that the printing adhesive is insensitive to is selected. For example, 405nm blue-violet light is used for curing, and 532nm green light is used for monitoring. The imaging laser 500 is directed towards the material bottle along the x-axis, that is, perpendicular to the curing beam. Similar to the curing optical path, the imaging laser 500 also needs to be expanded and collimated by a second shaping unit 142 to form a parallel beam 600 that can cover the entire printing area. After this parallel beam penetrates the material bottle and the printed product forming inside, it forms a product image with product outline and internal structural information. A camera 143 located on the side of the material bottle away from the imaging laser 141 is responsible for capturing the product image. Through this transmissive imaging design, the two-dimensional projection information of the printed product can be clearly and in real time acquired, providing a high-quality input signal for closed-loop control.

[0144] In some embodiments, the control module 130 includes an image processing unit and a feedback control unit. The image processing unit can acquire product images in real time and extract image features from the product images. The feedback control unit is used to compare the image features with the three-dimensional target model and, based on the deviation between the image features and the three-dimensional target model, control the adjustment module 110 to adjust the relative position of the material bottle and control the intensity of the curing laser 200 and the exposure time of the printing adhesive.

[0145] For example, the software control program of control module 130 also includes an image processing unit and a feedback control unit. The image processing unit can receive and process the product image from camera 143 in real time, and extract key image features from the original image through a series of image processing algorithms (such as edge detection and feature extraction), such as the actual outline, size, and center position of the printed product. Subsequently, the feedback control unit compares the extracted actual image features with the theoretical features that the three-dimensional target model should have at the current angle, thereby calculating the deviation between the two. Based on this deviation, the feedback control unit generates a series of control commands. On the one hand, it controls adjustment module 110 to adjust the relative position of the material bottle to compensate for position and orientation errors; on the other hand, it can also control curing module 120, for example, dynamically adjusting the intensity of curing laser 200 or the exposure time of printing adhesive to compensate for deviations in curing degree (such as under-curing or over-curing). Through this complete automated process of "imaging-processing-comparison-feedback", the system realizes online, intelligent, and closed-loop control of printing quality.

[0146] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0147] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A volumetric bioprinting method, characterized in that, include: Based on the three-dimensional target model to be printed, biological coordinate points are constructed in the printing adhesive inside the material bottle, and biological building blocks are injected into the biological coordinate points. Based on the three-dimensional target model to be printed, output the corresponding projection pattern at each predetermined angle, and modulate the curing laser into a dynamic pattern laser based on the projection pattern; The dynamic pattern laser is projected onto the material bottle along a first direction. The material bottle and the dynamic pattern laser are rotated relative to each other in a controlled manner. The printing adhesive is exposed by the dynamic pattern laser to generate a printed product. The product image of the printed product is acquired in real time, the image features of the product image are extracted, and the image features are analyzed and compared with the three-dimensional target model. If the image feature deviates from the expected image of the three-dimensional target model, adjust the relative position of the material bottle or adjust the focal plane of the dynamic pattern laser; if the grayscale value of the image feature deviates from the set grayscale value of the three-dimensional target model, adjust the power of the curing laser and / or the exposure time of the printing adhesive.

2. The volumetric bioprinting method according to claim 1, characterized in that, The controlled curing laser is modulated into a dynamic pattern laser based on the projected pattern, including: Emitting a curing laser; The diameter of the curing laser is increased and the curing laser is collimated to obtain a shaped beam; The projection beam is obtained by modulating the shaping beam based on the projection pattern; The zero-order light in the projected beam is eliminated to obtain the dynamic pattern laser.

3. The volumetric bioprinting method according to claim 1, characterized in that, The real-time acquisition of the printed product image includes: An imaging laser is emitted toward the material bottle along a second direction; The diameter of the imaging laser is increased and the imaging laser is collimated to obtain a parallel beam; The parallel light beam penetrates the printed product inside the material bottle to form the product image, and the camera is located on one side of the material bottle to receive the product image.

4. The volumetric bioprinting method according to claim 2, characterized in that, The extraction of image features from the product image includes: An image of the product is captured at set angles, and the outline of the solidified area of ​​the current printed product, the gray value, and the projection error between the current printed product and the three-dimensional target model at the current angle are calculated in real time.

5. The volumetric bioprinting method according to claim 4, characterized in that, Adjusting the relative position of the material bottles includes: If the outline of the solidified area of ​​the printed product is offset relative to the three-dimensional target model in the second direction, the material bottle is driven to perform displacement compensation along the second direction. If the outline of the solidified area of ​​the printed product is asymmetrical or there is a projection error between the current printed product and the three-dimensional target model at the current angle, the material bottle is driven to swing in an arc around the first axis and / or around the second axis. The first axis is parallel to the first direction, the second axis is parallel to the second direction, and there is an angle between the first direction and the second direction.

6. The volumetric bioprinting method according to claim 4, characterized in that, Adjusting the focal plane of the dynamic pattern laser includes: If the outline of the solidified area of ​​the printed product is offset relative to the three-dimensional target model in the first direction, then the position of the focal plane of the dynamic pattern laser in the first direction is adjusted.

7. The volumetric bioprinting method according to claim 4, characterized in that, Adjusting the power of the curing laser and / or the exposure time of the printing adhesive includes: If the grayscale value of the image feature is lower than the set grayscale value of the three-dimensional target model, then increase the power of the curing laser at subsequent angles or extend the exposure time of the printing adhesive. If the grayscale value of the image feature is higher than the set grayscale value of the three-dimensional target model, then the power of the curing laser at subsequent angles is reduced or the exposure time of the printing adhesive is shortened.

8. The volumetric bioprinting method according to any one of claims 1 to 7, characterized in that, The volumetric bioprinting method further includes: After printing is completed, the printed product is subjected to a full-cycle inspection, and a quality report is generated.

9. The volumetric bioprinting method according to any one of claims 1 to 7, characterized in that, The volumetric bioprinting method further includes: A matching liquid tank is provided on the outer periphery of the material bottle, and there is a gap between the matching liquid tank and the material bottle, and the space between the matching liquid tank and the material bottle is filled with matching liquid; The refractive index difference between any two of the following: the wall of the matching liquid tank, the matching liquid, the body of the material bottle, and the printing adhesive is 0-0.

05.

10. A printing system, characterized in that, The volumetric bioprinting method according to any one of claims 1 to 9, wherein the printing system comprises: An adjustment module is used to place the material bottle and adjust its relative position in multiple degrees of freedom; The curing module is capable of emitting the curing laser; The monitoring module is used to acquire images of the product in real time; The control module is capable of setting the projection pattern based on the three-dimensional target model to be printed, and controlling the curing module to modulate the curing laser into the dynamic pattern laser based on the projection pattern; the control module is capable of adjusting the relative position of the material bottle or adjusting the focal plane of the dynamic pattern laser based on the positional deviation between the image features and the expected image of the three-dimensional target model; the control module is also capable of adjusting the power of the curing laser and / or the exposure time of the printing adhesive based on the deviation between the grayscale value of the image features and the grayscale value set by the three-dimensional target model.

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