Scanning energy system for additive manufacturing and associated methods

Abstract

Systems (100) and methods for additive manufacturing are provided. In some embodiments, a method for additive manufacturing includes forming a portion of an additive manufacturing object within a reservoir (104) of a solidifiable material (102) by causing a plurality of energy beams (110) of a plurality of energy sources (108) to scan through a plurality of respective scan regions in the solidifiable material. The scan regions can overlap at one or more object locations such that a combined energy dose delivered to the one or more object locations by two or more of the energy beams is greater than or equal to a threshold dose for causing the solidifiable material to solidify. The method can also include advancing the reservoir of the solidifiable material relative to the energy sources. The forming process and the advancing process can be repeated to manufacture the additive manufacturing object.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 580,091, filed September 1, 2023, and U.S. Provisional Application No. 63 / 594,678, filed October 31, 2023, the disclosures of each of which are incorporated herein by reference in their entirety. Technical Field

[0003] This technology generally relates to manufacturing, and more specifically to scanning energy systems and associated methods for additive manufacturing. Background Technology

[0004] Additive manufacturing (also known as “3D printing”) encompasses various techniques for creating 3D objects using additive processes. Conventional additive manufacturing processes typically involve building 3D objects from multiple layers of material. However, conventional layer-by-layer additive manufacturing processes can be impractical for large-scale manufacturing due to their slow printing speeds (e.g., printing a single object can take hours), as printing speed generally depends on the number of layers in the object, the thickness of each layer, and the time taken to print each layer. Volumetric additive manufacturing processes can be used to produce objects from a fixed volume of resin in a single printing step, without requiring layer-by-layer construction, thus offering significantly faster printing speeds (e.g., an entire object can be printed in seconds). However, volumetric additive manufacturing processes typically require specialized hardware and materials, which can increase costs and limit the range of available materials. Attached Figure Description

[0005] Many aspects of this disclosure can be better understood by referring to the following figures. The components in the figures are not necessarily drawn to scale. Rather, the focus is on clearly illustrating the principles of this disclosure.

[0006] Figure 1A This is a partial schematic front cross-sectional view of an additive manufacturing system configured according to an embodiment of the present technology.

[0007] Figure 1B yes Figure 1A A partial schematic side section view of the system.

[0008] Figure 2 This is a partial schematic diagram illustrating the selective consolidation of a curable material using multiple energy beams according to an embodiment of the present technology.

[0009] Figure 3A and Figure 3B This is a partial schematic diagram illustrating the selective consolidation of a curable material using multiple energy beams according to an embodiment of the present technology.

[0010] Figure 4ADuring the operation phase according to embodiments of this technology Figure 1A and Figure 1B A partial schematic front cross-sectional view of the system.

[0011] Figure 4B yes Figure 4A A partial schematic side section view of the system.

[0012] Figure 4C This is during the subsequent operation phase according to embodiments of the present technology. Figure 1A and Figure 1B A partial schematic front cross-sectional view of the system.

[0013] Figure 4D yes Figure 4C A partial schematic side section view of the system.

[0014] Figure 5A This is a partial schematic front cross-sectional view of an additive manufacturing system including three energy sources according to an embodiment of the present technology.

[0015] Figure 5B This is a partial schematic side view of an additive manufacturing system with an angled energy source according to an embodiment of the present technology.

[0016] Figure 5C This is a partial schematic side view of an additive manufacturing system with an offset energy source according to an embodiment of the present technology.

[0017] Figure 6A This is a partial schematic diagram of an energy beam with a constant diameter according to an embodiment of the present technology.

[0018] Figure 6B This is a partial schematic diagram of an energy beam with a converging diameter according to an embodiment of the present technology.

[0019] Figure 7 This is a partial schematic front cross-sectional view of an additive manufacturing system including a reservoir with angled walls, according to an embodiment of the present technology.

[0020] Figure 8A This is a partial schematic front cross-sectional view of an additive manufacturing system including a reflective element according to an embodiment of the present technology.

[0021] Figure 8B This is a partial schematic front cross-sectional view of an additive manufacturing system including a reservoir with a reflective element, according to an embodiment of the present technology.

[0022] Figure 8C This is a partial schematic front cross-sectional view of an additive manufacturing system including a reservoir used as a reflective element, according to an embodiment of the present technology.

[0023] Figure 8D This is a partial schematic front cross-sectional view of an additive manufacturing system including a reservoir with an array of reflective elements, according to an embodiment of the present technology.

[0024] Figures 9A to 9C Various cured patterns that can be used to form additive manufacturing objects according to embodiments of the present technology are shown.

[0025] Figure 10A This is a flowchart illustrating a method for determining scanning parameters for manufacturing an additively manufactured object according to an embodiment of the present technology.

[0026] Figure 10B A method for determining scan parameters using a predictive model, according to an embodiment of the present technology, is illustrated.

[0027] Figure 11 This is a schematic block diagram illustrating a workflow for determining the energy intensity for manufacturing an additively manufactured object according to an embodiment of the present technology.

[0028] Figure 12 This is a flowchart illustrating a method for manufacturing an additive manufacturing object according to an embodiment of the present technology.

[0029] Figure 13 This is a flowchart illustrating a method for manufacturing and processing additively manufactured objects according to an embodiment of the present technology.

[0030] Figure 14A A representative example of a tooth repositioning appliance configured according to embodiments of the present technology is shown.

[0031] Figure 14B A tooth repositioning system comprising multiple appliances is shown according to an embodiment of the present technology.

[0032] Figure 14C A method for orthodontic treatment using multiple appliances according to an embodiment of the present technology is illustrated.

[0033] Figure 15 A method for designing orthodontic appliances according to embodiments of the present technology is shown.

[0034] Figure 16 A method for designing or manufacturing orthodontic treatment and / or appliances for digital planning according to embodiments of the present technology is illustrated.

[0035] Figure 17A This is a thermal image showing the globally optimized optical dose using three collimated lasers and two reflectors.

[0036] Figure 17B It is used for Figure 17A The optimized target shape of the heat map image.

[0037] Figure 18A This is a thermal image showing the globally optimized optical dose using five collimated lasers and two reflectors.

[0038] Figure 18B It is used for Figure 18A The optimized target shape of the heat map image.

[0039] Figure 19A This is a thermal image showing the globally optimized optical dose using ten collimated lasers and two reflectors.

[0040] Figure 19B It is used for Figure 19A The optimized target shape of the heat map image.

[0041] Figure 20A This is a thermal image showing a locally optimized optical dose using ten collimated lasers and two reflectors.

[0042] Figure 20B It is used for Figure 20A The optimized target shape of the heat map image.

[0043] Figure 21A This is a thermal image showing a locally optimized optical dose using ten converging lasers and two reflective walls.

[0044] Figure 21B It is used for Figure 21A The optimized target shape of the heat map image.

[0045] Figure 22A It is a heat map image showing the shape of the target object.

[0046] Figure 22B This is a thermal map showing the predicted global optical dose using five lasers and layer-by-layer scanning.

[0047] Figure 22C This is a thermal map showing the predicted global optical dose using five lasers and volumetric scanning.

[0048] Figure 22D This is a thermal map showing the predicted global optical dose using a laser and layer-by-layer scanning. Detailed Implementation

[0049] This technology relates to additive manufacturing of objects such as dental appliances. For example, in some embodiments, a method for manufacturing an additively manufactured object includes forming a portion of the additively manufactured object within a reservoir of curable material using a first energy beam from a first energy source and a second energy beam from a second energy source. The first energy beam may scan through a first scanning region within the reservoir of curable material, while the second energy source may scan through a second scanning region within the reservoir of curable material. The second scanning region may overlap with the first scanning region at one or more object locations such that the combined energy dose delivered to the object locations is greater than or equal to a threshold dose for solidifying the curable material, thereby forming a portion of the additively manufactured object. In contrast, the combined energy dose delivered to other locations in the curable material may remain below the threshold dose, such that the curable material does not solidify at these locations. The method may also include advancing the reservoir of curable material relative to the first and second energy sources. The forming and advancing processes may be repeated to manufacture the entire additively manufactured object.

[0050] In some embodiments, this technology provides a software algorithm for determining scanning parameters for manufacturing an additively manufactured object using multiple energy sources as described herein. For example, the software algorithm may be configured to perform the following operations: receive a 3D digital representation of the object to be manufactured; generate multiple 2D cross-sections from the 3D digital representation; determine scanning parameters for multiple energy sources to form multiple 2D cross-sections of the object from a curable material; and generate instructions for manufacturing the object from the curable material using the multiple energy sources with the scanning parameters.

[0051] Compared to conventional additive manufacturing techniques, this technology offers numerous advantages. For example, while some embodiments of this technology may involve forming objects via a layer-by-layer process, the thickness of a single layer can be significantly greater than the layer thickness in conventional additive manufacturing processes such as stereolithography (SLA), resulting in significantly faster printing speeds. The additive manufacturing process disclosed herein also allows for the fabrication of objects without the need for temporary support structures to attach them to the build platform, thereby reducing the amount of post-processing required to prepare objects for use. Furthermore, unlike conventional volumetric printing techniques (e.g., computational axial lithography (CAL) volumetric printing requires a rotating resin container with optically transparent walls, and xolography requires photoinitiators activated by two different wavelengths), the systems and methods described herein do not require highly specialized hardware and materials. Additionally, the systems and methods described herein can continuously solidify 2D object cross-sections as the curable material continuously advances through the scanning region of the energy source, allowing compatibility with conveyor-based mechanisms for uninterrupted, high-throughput printing of objects.

[0052] The software algorithm disclosed herein for calculating scanning parameters in additive manufacturing processes is computationally simpler than algorithms used in conventional volumetric printing techniques, while also providing precise delivery of the correct light dose to each voxel in the printed volume to ensure the accuracy of the printed object. For example, the software algorithm described herein can provide an optimization procedure to calculate the ideal laser intensity, laser position, reflective surface orientation, etc., to achieve the desired global light dose distribution, while taking into account laser transmission, reflection, diffraction, light attenuation, thermal buildup, and / or other phenomena that may affect the degree of resin curing and / or the delivered dose. Therefore, this technique can be used to produce large quantities of additively manufactured objects in a rapid, accurate, and cost-effective manner.

[0053] Embodiments of this disclosure will be described more fully below with reference to the accompanying drawings, in which the same reference numerals denote the same elements in several figures, and exemplary embodiments are illustrated in the drawings. However, the embodiments of the claims may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. The examples set forth herein are non-limiting examples and are merely examples of other possible examples.

[0054] As used herein, the terms “vertical,” “lateral,” “upper,” “lower,” “left,” “right,” etc., can refer to the relative orientation or position of a feature of the embodiments disclosed herein, given the orientation shown in the figures. For example, “upper” or “topmost” can refer to a feature positioned closer to the top of the page than another feature. However, these terms should be interpreted broadly to include embodiments with other orientations, such as inverted or tilted orientations, wherein top / bottom, above / below, above / below, up / down, and left / right can be interchanged depending on the orientation.

[0055] The headings provided herein are for convenience only and do not define the scope or meaning of the claimed technology. Embodiments under any heading may be used in conjunction with embodiments under any other heading. I. Additive manufacturing using scanning energy systems

[0056] Figures 1A to 4D An additive manufacturing system 100 configured according to an embodiment of the present technology is shown. Specifically, Figure 1A This is a partial schematic front cross-sectional view of system 100. Figure 1B It is a partial schematic side cross-sectional view of system 100, and Figures 2 to 4D The operation of system 100 is shown in various aspects.

[0057] Let's refer to each other first. Figure 1A and Figure 1BSystem 100 includes a curable material 102 within a reservoir 104 on platform 106, and multiple energy sources 108a, 108b (collectively, "energy sources 108") that output corresponding energy beams 110a, 110b (collectively, "energy beams 110"). Energy beams 110 can scan through the curable material 102 to selectively solidify the curable material 102, thereby forming one or more additively manufactured objects, as described in more detail below. For example, system 100 can be used to directly manufacture orthodontic appliances (e.g., braces, palatal expanders, retainers, attachment placement devices, attachments), restorative objects (e.g., crowns, veneers, implants), and / or other dental appliances (e.g., oral sleep apnea appliances, oral protectors). Additional examples of dental appliances and associated methods suitable for this technology are described in Section II below.

[0058] The curable material 102 may consist of one or more reactive components that change form upon exposure to energy (e.g., electromagnetic, acoustic, or radiant energy) generated by an energy source 108. For example, the change in form may include a change from a monomeric form to an oligomer and / or polymeric form, a change from an amorphous form to a crystalline form, a change from a liquid or semi-liquid form to a solid or semi-solid form, a change from a particulate or filamentous form to a continuous solid form, or a change from a non-crosslinked form to a crosslinked form, or a combination thereof.

[0059] For example, the curable material 102 may be a resin. The resin may consist of one or more polymerizable components, such as one or more monomers, oligomers, and / or reactive polymers. The polymerizable components may be any molecules or compounds capable of forming bonds with other polymerizable components, thereby producing larger molecules with increased molecular weights. In some embodiments, the bonding reaction occurs multiple times, such that the molecular weight of the resulting molecule increases with each successive bonding reaction. Examples of bonding reactions suitable for use with the techniques described herein include, but are not limited to, free radical polymerization, ionic polymerization (e.g., cationic polymerization, anionic polymerization), condensation polymerization, metathesis polymerization, Diels-Alder reaction, photodimerization, carbene formation, azene formation, and suitable combinations thereof.

[0060] The resin may initially be in a liquid state at room temperature (e.g., 20°C) or at elevated temperatures (e.g., in the range of 50°C to 120°C). When exposed to energy, the polymerizable component undergoes polymerization and / or other bonding reactions. Exposure to sufficiently high energy doses can cause the polymerizable component to polymerize above the resin's gel point, thereby causing the resin to solidify (e.g., gel). As further described below, energy source 108 can be used to deliver energy doses exceeding a threshold dose to solidify the resin at selected locations corresponding to the geometry of the object to be formed, while the remaining locations of the resin receive lower energy doses and therefore do not solidify.

[0061] In some embodiments, a polymerizable component (e.g., a low molecular weight monomer, oligomer, polymer) forms a high-modulus phase within the polymeric material. In this embodiment, the phase can provide sufficient strength to the green object to withstand post-processing and / or guide the final shape of the additively manufactured object. Alternatively, the polymerizable component can form a low-modulus phase within the polymeric material or otherwise reduce the local modulus of the object.

[0062] In some embodiments, the polymerizable component includes one or more of the following: acrylate monomers, methacrylate monomers, thiol monomers, vinyl acetate monomers, vinyl ether monomers, vinyl chloride monomers, vinyl silane monomers, vinyl siloxane monomers, styrene monomers, allyl ether monomers, acrylonitrile monomers, butadiene monomers, norbornene monomers, maleate monomers, fumarate monomers, epoxide monomers, anhydride monomers, or hydroxyl monomers. In some embodiments, the polymerizable component includes one or more of the following: radically polymerizable groups, cationicly polymerizable groups, or anionicly polymerizable groups. In some embodiments, the polymerizable component includes one or more reactive functional groups, such as one or more of the following: acrylates, methacrylates, acrylamides, vinyl groups, vinyl ethers, thiols, allyl ethers, norbornene, vinyl acetate, maleate, fumarate, methylene malonate, maleimide, epoxides, cyclic strained ethers, cyclic strained sulfides, cyclic esters, cyclic carbonates, cyclic silanes, cyclic siloxanes, hydroxyl groups, amines, isocyanates, terminal isocyanates, acyl chlorides, activated esters, oxetanes, Diels-Alder reactive groups, furans, cyclopentadiene, acid anhydrides, groups that promote photodimerization (e.g., anthracene, acenaphthene, or coumarin), groups that photodegrade into reactive substances (e.g., Norrish type 1 and 2 materials), azides, derivatives thereof, or combinations thereof. Additional examples of polymerizable components that may be used are provided in the following documents: U.S. Patent No. 10,495,973 and U.S. Patent Publications Nos. 2021 / 0147672, 2021 / 0395420, 2022 / 0380502 and 2023 / 0021953, the disclosures of each of which are incorporated herein by reference in their entirety.

[0063] In some embodiments, the curable material 102 is or includes a thiol-olefin resin. Thiol-olefin resins are generally not oxygen-suppressed, and therefore may be difficult to print using conventional additive manufacturing techniques such as SLA. In contrast, despite the lack of oxygen suppression, the additive manufacturing process of this technique is still able to form 3D objects from thiol-olefin resins at high resolution.

[0064] In some embodiments, the curable material 102 comprises one or more semi-crystalline materials. During printing, the material can be a liquid or a crystal. Examples of resins comprising semi-crystalline materials are provided in U.S. Patent Publication No. 2021 / 0147672, the disclosure of which is incorporated herein by reference in its entirety. This technique can be advantageous for printing semi-crystalline materials because the temperature of the material can be raised above T0. m This value can make the material transparent or nearly transparent (e.g., compared to crystalline forms that may scatter light). For example, reservoir 104 and / or other components of system 100 may include one or more heating elements to allow the curable material 102 to be heated above T.m The temperature, as further described below. In contrast, conventional additive manufacturing techniques such as SLA may not be able to print with high T m A valuable semi-crystalline material.

[0065] In some embodiments, this technology allows for high T m Materials (such as high T) m Thermoplastics are mixed with reactive resins and / or formulated into reactive polymers, and then subjected to a reaction at a temperature higher than their respective T0. m Printing is performed at the specified temperature. Residual unconsolidated material can be removed from the additively manufactured object during post-processing, for example, by melting and flowing the cross-linked and / or crystalline regions in the solvent and / or the uncross-linked regions. For some materials (e.g., thiols-olefins or other step-growth polymers), the T value of the unreacted material is... m Less than the T of the material in the reaction state m Therefore, unreacted material can be liquid at the printing temperature and can crystallize upon exposure to a certain amount of energy. This method allows for material consolidation without the need for covalent cross-linking. Furthermore, by allowing the crystalline regions to remain solid while allowing the less cured material to flow away, the printed green object can be separated from the remaining resin.

[0066] In some embodiments, the curable material 102 comprises a plurality of different resins, such as two, three, four, five or more resins. Some or all of the resins are miscible with each other, or some or all of the resins are immiscible with each other. In some embodiments, the different resins are initially present in the curable material 102, while in other embodiments, one or more resins may be added to the curable material 102 before, during and / or after each printing cycle. The resin may be added within the volume of the curable material 102, added to the surface of the curable material 102, or a suitable combination thereof. The resin may be added using any suitable deposition technique, such as extrusion, inkjet, injection, spraying, casting, etc. Different resins may have different properties, which can be used to produce composite materials in which different parts of the material have different properties (e.g., stiffness, strength, T). g For example, some resins may be reactive to the energy generated by energy source 108, while others may not be reactive to the energy generated by energy source 108. In this embodiment, other resins may be reactive to other energies, such as light, heat, and / or pressure applied after printing (e.g., during post-curing and / or other post-processing).

[0067] In some embodiments, the curable material 102 includes one or more additives, such as catalysts, reaction inhibitors, blockers, viscosity modifiers, fillers, fibers, particles, adhesives, reactive diluents, solvents, pigments and / or dyes, stabilizers, surfactants, release compounds, bioactive compounds (e.g., drugs, enzymes, antibiotics, cells, hormones), inert polymers, inert oligomers, etc., or suitable combinations thereof.

[0068] For example, in some embodiments, the curable material 102 includes a catalyst that, when exposed to energy, forms a reactive substance that catalyzes a bonding reaction. The catalyst may be a photocatalyst activated by absorbing light (e.g., infrared, visible, or ultraviolet (UV) light) or otherwise generated. Examples of photocatalysts include, but are not limited to, photoinitiators (e.g., radical initiators), photoacid generators, and photobase generators. In some embodiments, the photoinitiator is activated by light of a single wavelength, while in other embodiments, the photoinitiator may require two or more different wavelengths of light to activate. In some embodiments, the photoinitiator may need to absorb one or more photons to become active. In some embodiments, photon upconversion (e.g., two-photon upconversion) is used to generate higher-energy photons from two or more lower-energy photons.

[0069] In some embodiments, the curable material 102 includes a reaction inhibitor to prevent curing of the curable material 102 in locations where curing is not required. The reaction inhibitor may be a photoactivated inhibitor activated by light (e.g., infrared, visible, or UV light). Alternatively, the reaction inhibitor may be removed from the portion of the curable material 102 that requires curing, for example, by degrading the reaction inhibitor using light or other energy.

[0070] In some embodiments, the curable material 102 includes a blocking agent that limits the depth to which energy penetrates the curable material 102 during the additive manufacturing process. For example, the blocking agent may be a light-blocking agent that absorbs the irradiation wavelength responsible for inducing a photoreaction (e.g., activating a photocatalyst or photodimerization reaction). In some embodiments, the light-blocking agent is activated by an energy source such as light (e.g., spiropyran and other photochromic substances that are activated by light and alter their absorption). However, in other embodiments, the curable material 102 does not include any blocking agent.

[0071] In some embodiments, the curable material 102 includes a viscosity modifier. The viscosity modifier may be a component that increases the viscosity of the curable material 102 (e.g., a filler, binder, thixotropic agent). Alternatively, the viscosity modifier may be a component that decreases the viscosity of the curable material 102 (e.g., a reactive diluent, solvent).

[0072] In some embodiments, the curable material 102 includes a filler. The filler may be organic or inorganic, such as fumed silica, core-shell particles, talc, titanium dioxide, sugar, nanocellulose, graphite, carbon black, carbon nanotubes, etc.

[0073] In some embodiments, the curable material 102 includes a plurality of fibers. The fibers may be organic or inorganic fibers (e.g., glass fibers). The fibers may be transparent, translucent, or opaque. Optionally, the curable material 102 may be matched to the refractive index of the fibers. The fibers may have surfaces that promote adhesion, such as having reactive chemical properties and / or mechanical roughness. The fibers may be placed throughout the entire curable material 102, or may be placed only in certain areas of the curable material 102 to be fully incorporated into, partially incorporated into, or not incorporated into the additive manufacturing object. The fibers may be randomly distributed within the curable material 102, or they may be aligned. For example, the fibers may be aligned along the long direction (e.g., length) or short direction (e.g., width or height) of the object. In embodiments where the object is a dental appliance such as an orthodontic appliance, the fibers may be aligned along the long arch of the dental appliance rather than along the height of the dental appliance. Various techniques can be used to align the fibers. In some embodiments, the fibers are aligned by extruding the curable material 102 having fibers in the desired alignment direction. Alternatively, the fibers can be trapped in the viscous resin, and the resin can move in a desired alignment direction, which can align the fibers with the direction of resin movement. Resin movement can occur during resin extrusion or deposition, or it can be mechanically accomplished by moving a solid object through the fiber-containing resin.

[0074] In some embodiments, the curable material 102 comprises a plurality of particles. The particles may be organic or inorganic. The particles may be transparent, translucent, or opaque. Optionally, the curable material 102 may match the refractive index of the particles. The particles may have surfaces that promote adhesion, such as reactive chemical properties and / or mechanical roughness. The particles may be placed throughout the entire curable material 102, or may be placed only in certain areas of the curable material 102 to be fully incorporated into, partially incorporated into, or not incorporated into the additive manufacturing object. The particles may be dispersed or aggregated within the curable material 102.

[0075] In some embodiments, the curable material 102 includes an adhesive. The adhesive may be a high molecular weight polymer added to the curable material 102 to increase viscosity and / or enhance various material properties after curing, such as polymethyl methacrylate, acrylonitrile butadiene styrene (ABS), etc.

[0076] In some embodiments, the curable material 102 includes a reactive diluent. The reactive diluent can reduce the viscosity of the curable material 102 while also reacting with one or more other components to form part of the object. For example, the reactive diluent may be combined with oligomers and / or reactive polymers within the curable material 102.

[0077] In some embodiments, the curable material 102 includes a solvent. The solvent may reduce the viscosity of the curable material 102 and / or make two or more components of the curable material 102 compatible.

[0078] In some embodiments, the curable material 102 includes pigments and / or dyes. Pigments and / or dyes (e.g., titanium dioxide, red dye #40, carbon black) can add color and / or other functionality to an object.

[0079] In some embodiments, the curable material 102 includes a stabilizer configured to stabilize one or more components (e.g., to prevent precipitation, aggregation, or degradation). For example, the stabilizer may be an emulsifier that stabilizes the components of an emulsion.

[0080] In some embodiments, the curable material 102 includes a surface-active compound. The surface-active compound can enhance the wetting or adhesion of the curable material 102 and / or the object to another surface. Alternatively or in combination, the surface-active compound can promote debonding of the curable material 102 and / or the object from another surface. Examples of surface-active compounds include, but are not limited to, waxes, silicone compounds, silanes, fluorinated compounds, etc.

[0081] Optionally, some or all of the components of the curable material 102 may serve more than one function within the curable material 102 and / or the additively manufactured object. For example, the reactive diluent may be a monomer or a viscosity modifier; carbon black may be a pigment or a light-blocking agent; and so on.

[0082] In some embodiments, the curable material 102 includes at least one solid component, such as an electronic package (e.g., a sensor), a battery, a metal component (e.g., a metal wire, a metal sheet), a plastic component (e.g., a plastic wire, a plastic sheet), a reinforcing structure, a support structure (e.g., a temporary or permanent support structure), a handle (e.g., a temporary or permanent handle), a component that can be attached to other components (e.g., a hook, a button), etc. The solid component may or may not be a permanent part of the additive manufacturing object. Additional examples of solid components that may be added to the curable material 102 are provided in the following documents: U.S. Patent Publication No. 2021 / 0220087, U.S. Patent Publication No. 2022 / 0110717, and U.S. Provisional Application No. 63 / 381,097, the disclosures of which are incorporated herein by reference in their entirety.

[0083] Solid components can be placed on or within the curable material 102 at a desired location by a human operator, via a robotic arm, or using any other suitable technique. The solid components can be held in place on or within the curable material 102 at a desired location by a support structure (e.g., via reservoir 104 and / or platform 106) and / or by the viscosity of the curable material 102. In some embodiments, the solid component is placed into the curable material 102 before energy is applied to the curable material 102 via energy source 108. Alternatively, the curable material 102 can be added after the solid component has been placed in the desired location.

[0084] When a solid component is present in the curable material 102, the solid component may be completely transparent to the energy generated by the energy source 108 or may not be completely transparent to the energy. In embodiments where the solid component is not completely transparent to the energy, the curable material 102 beneath the solid component may be a “shadowed area” that may be difficult to cure or may not be curable at all. In such embodiments, the presence of the shadowed area does not cause any problems as long as the solid component is in a fixed position and the uncured shadowed area is contained within the curing volume of the curable material 102. If desired, the uncured shadowed area can be cured during a post-curing process after printing. Alternatively, another curable material that is unresponsive to the energy from the energy source 108a may be placed in the shadowed area and may be activated by another energy source and / or over time during deposition or after printing. Alternatively or in combination, chemical systems that can cure into the shadowed area, such as cationic reactions, may be used.

[0085] The solid component may or may not be completely encapsulated by the curable material 102. For example, the solid component may be located inside the additively manufactured object or on the surface of the additively manufactured object. In some embodiments, the solid component is present in the curable material 102, and unreacted shaded areas not encapsulated in the curable material are intentionally left.

[0086] In some embodiments, certain types of solid components are present in the curable material 102 that are not cured and incorporated into the additively manufactured object. For example, the solid component may be a handle for the object or a sheet at the bottom of the reservoir 104 for supporting the object, which may be useful for post-processing of the object. In some embodiments, the handle facilitates removal of the object from the remaining curable material 102 and may facilitate further processing, such as providing a structure for gripping the object and moving it to other sites (e.g., solvent washing, centrifugation, etc.). Furthermore, the solid component may not be attached to the object. For example, a porous structure (e.g., a metal or plastic mesh or basket) may initially be present in the curable material 102; after printing, the porous structure may be lifted from the curable material 102, thereby separating the object from the remaining curable material 102 and / or facilitating the transport of the object for further processing, such as centrifugation, solvent washing, post-curing exposure, post-curing heat exposure, post-curing chemical modification, etc.

[0087] In some embodiments, a curable material 102 (e.g., a resin) is used at a selected printing temperature. The printing temperature can be room temperature (e.g., 25°C), an elevated temperature (e.g., at least 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 150°C, or 200°C), or a lower temperature (e.g., not exceeding 20°C, 10°C, 0°C, -10°C, -20°C, -30°C, -40°C, -50°C, or -60°C). In some embodiments, the printing temperature is within the range of -60°C to 0°C, 0°C to 100°C, 100°C to 120°C, 120°C to 150°C, 150°C to 200°C, or greater than 200°C.

[0088] The printing temperature can be controlled using one or more heating elements and / or one or more cooling elements. The heating and / or cooling elements may be coupled to or a portion of reservoir 104, or may be another component of system 100, as further described below. In some embodiments, the curable material 102 is heated or cooled from an initial temperature (e.g., room temperature) to the printing temperature within a time not exceeding 10 minutes, 5 minutes, 2 minutes, 1 minute, 30 seconds, or 10 seconds. Optionally, the curable material 102 is held at the printing temperature for a time not exceeding 10 minutes, 5 minutes, 2 minutes, 1 minute, 30 seconds, or 10 seconds. Optionally, the curable material 102 may return from the printing temperature to the initial temperature within a time not exceeding 10 minutes, 5 minutes, 2 minutes, 1 minute, 30 seconds, or 10 seconds.

[0089] In some embodiments, the entire curable material 102 is maintained at the same temperature. Alternatively, certain portions of the curable material 102 may be at different temperatures than other portions of the curable material 102, which can be used to create object portions with different material properties. In such embodiments, the temperature of different portions of the curable material 102 can be selectively controlled, such as by selectively applying energy to certain portions of the curable material 102 (e.g., using infrared light, microwaves, placing heating elements at specific locations), and / or by selectively cooling certain portions of the curable material 102 (e.g., using cold fingers, thermoelectric coolers (TECs), cold air streams, CO2 snow sprayers). Additional examples of techniques for temperature control are provided in U.S. Patent No. 11,661,468, the disclosure of which is incorporated herein by reference in its entirety.

[0090] The curable material 102 may have any suitable viscosity at the printing temperature, such as in the range of 10 cP to 100 cP, 100 cP to 1000 cP, 1000 cP to 10,000 cP, 10,000 cP to 100,000 cP, or 100,000 cP to 1,000,000 cP. In some embodiments, the curable material 102 is solid at the printing temperature. In some embodiments, the curable material 102 is thixotropic and / or shear-thinning.

[0091] In some embodiments, the curable material 102 is optically transparent or translucent. For example, the curable material 102 may contain at least 50%, 60%, 70%, 80%, 90%, 95%, or 99% of the energy at one or more wavelengths generated by the energy source 108 (e.g., at a path length of 1 cm).

[0092] The reservoir 104 may be a tank, can, liquid tank, tray, or other container suitable for containing the curable material 102. The reservoir 104 may be large enough that its internal volume is equal to or greater than the volume of the object to be manufactured. For example, the height of the reservoir 104 may be greater than or equal to the maximum height of the object, the length of the reservoir 104 may be greater than or equal to the total length of the object, and the width of the reservoir 104 may be greater than or equal to the total width of the object. Although the reservoir 104 is depicted as having a rectangular cross-sectional shape, in other embodiments, the reservoir 104 may have different cross-sectional shapes, such as square, cylindrical, semi-cylindrical, trapezoidal, etc. In some embodiments, the shape of the reservoir 104 is similar to the shape of the object to be printed.

[0093] In the illustrated embodiment, the reservoir 104 includes a bottom wall 112 and a plurality of side walls 114. The bottom wall 112 and / or the side walls 114 may be optically transparent to the energy beam 110 or may be opaque to the energy beam 110. In some embodiments, the bottom wall 112 and / or the side walls 114 highly absorb the energy beam 110, such that little or no energy is reflected from or otherwise directed out of the reservoir 104 and / or reflected back into the reservoir 104. Alternatively or in combination, the energy beam 110 may be effectively coupled out of the reservoir 104 by the shape of the reservoir 104 itself and / or via a surface coating (e.g., an anti-reflective coating).

[0094] The reservoir 104 may also include an opening 116 at its upper portion, exposing the upper surface of the curable material 102 and allowing direct access by the energy beam 110 from the energy source 108. Alternatively, the reservoir 104 may include an upper wall such that the curable material 102 is completely enclosed within the reservoir 104. In this embodiment, the upper wall may be optically transparent to allow the energy beam 110 to pass through. Optionally, the upper wall may include an anti-reflective coating to enhance energy transfer through the upper wall.

[0095] In some embodiments, the upper wall is a liquid, such as oil (e.g., silicone oil), wax, water, or a resin with or without an initiator component (e.g., the surface layer of the resin may include an initiator component activated by heat and / or a wavelength different from that of the curable material 102). The liquid may be insoluble in the curable material 102. The liquid may restrict oxygen diffusion to promote curing at the surface of the curable material 102. The liquid may have a sufficiently low viscosity to flow and level, thereby providing a smooth, horizontal surface through which the energy beam 110 can be transmitted. The liquid may have a different refractive index than the curable material 102. For example, in some embodiments, the refractive index of the liquid is lower than that of the curable material 102, for example, to promote coupling of the energy beam 110 into the curable material 102. Alternatively, the refractive index of the liquid may be higher than that of the curable material 102, for example, to restrict coupling of the energy beam 110 into the curable material 102 at certain angles.

[0096] In some embodiments, the atmosphere above the surface of the curable material 102 may be inert to the reaction within the curable material 102, for example, to promote curing at the surface of the curable material 102 when needed. For example, if free radical polymerization is used to cure the curable material 102, an atmosphere of nitrogen, carbon dioxide, argon, xenon, or other gases that do not react with free radicals may be used. As another example, if cationic polymerization is used to cure the curable material 102, an air atmosphere with almost no water and / or alcohol to no water and / or alcohol may be used.

[0097] Alternatively, in embodiments where the curable material 102 is highly viscous and exhibits little or no flow after deposition, some or all of the sidewalls 114 of the reservoir 104 may be omitted (e.g., the reservoir 104 may include only two lateral sidewalls 114 or may not include sidewalls 114 at all). Thus, the reservoir 104 may be a platform, sheet, stage, or other generally planar substrate that supports the curable material 102 on a surface rather than housing the curable material 102 within an internal cavity.

[0098] The curable material 102 can be deposited into the reservoir 104 as one or more layers. These layers can each have a corresponding layer thickness T, which can be the same or different for different layers. The layer thickness T can be in the range of 1 μm to 10 μm, 10 μm to 100 μm, 100 μm to 1 mm, 1 mm to 1 cm, or 1 cm to 10 cm, or can be greater than 10 cm. In some embodiments, the layer thickness T is greater than or equal to the height of the additively manufactured object to be formed, such that a single layer of the curable material 102 is deposited in the reservoir 104. However, in other embodiments, the layer thickness T can be less than the height of the object, such that multiple layers of the curable material 102 are sequentially deposited in the reservoir 104 to form the object. The layer thickness T can be greater than the layer thickness used in conventional additive manufacturing processes such as SLA. Furthermore, unlike conventional additive manufacturing processes such as SLA, the layer thickness T can be greater than the resolution of the system 100, which can correspond to the minimum voxel size of the system 100. For example, the minimum voxel size of system 100 (e.g., minimum voxel height) may be less than or equal to 200 μm, 100 μm, 50 μm, 20 μm, 10 μm, 5 μm, or 1 μm. In some embodiments, the layer thickness T is 2, 3, 4, 5, 10, 100, or 1000 times larger than the minimum voxel height.

[0099] In embodiments where the curable material 102 scatters and / or absorbs the energy beam 110, layer printing can maintain the resolution of the printed object within acceptable limits. However, since the layers for this technique can be larger than the voxel height, the overall printing process can be faster than in conventional additive manufacturing methods. In some cases, as the absorbance and / or scattering of the curable material 102 increases, the layer height can be reduced to be closer to or equal to the voxel height.

[0100] In some embodiments, reservoir 104 includes one or more temperature control elements that can be used to adjust the temperature of the curable material 102 to a desired temperature as described elsewhere herein. For example, the temperature control element may include one or more heating elements, such as a heater, hot plate, heating lamp, or heating fluid. Alternatively or in combination, the temperature control element may include one or more cooling elements, such as a cold finger, TEC, or cooling fluid. The temperature control element may be located at any suitable portion of reservoir 104, such as on or within bottom wall 112, on or within side wall 114, inside reservoir 104, near an opening of reservoir 104, or a suitable combination thereof.

[0101] Alternatively or in combination, system 100 may include one or more temperature control elements that are separate from but sufficiently close to reservoir 104 to control the temperature of the curable material 102. For example, system 100 may include a separate energy source that heats the curable material 102 using infrared energy, electrical energy, microwave energy, etc. In some embodiments, the infrared energy is controlled such that selective heating (e.g., 2D or 3D selective heating) of segments of the curable material 102 can be achieved, for example, using techniques described in the following document: U.S. Patent No. 11,661,468, the disclosure of which is incorporated herein by reference in its entirety. The temperature control elements may also be positioned on or within platform 106 supporting reservoir 104.

[0102] In some embodiments, reservoir 104 includes one or more ports for introducing curable material 102 into reservoir 104 and / or for discharging curable material 102 from reservoir 104. The ports may be located at any suitable portion of reservoir 104, such as bottom wall 112, side wall 114, or a combination thereof. Optionally, system 100 may include additional components to facilitate removal of curable material 102 from reservoir 104 after the additive manufacturing process is complete, such as a source of compressed gas for ejecting curable material 102 from reservoir 104, and / or a source of solvent for flushing curable material 102 out of reservoir 104 and / or rinsing it off from the object surface. In some embodiments, a second curable material (e.g., a second resin) is introduced into reservoir 104 after removal of curable material 102, or to displace curable material 102 and / or any other residual material (e.g., gas, solvent) from reservoir 104. In this embodiment, the second curable material can be used to manufacture additional parts of an object and / or other additively manufactured objects that are not part of a previously manufactured object.

[0103] The reservoir 104 can be positioned on a platform 106, which can be a table, conveyor belt, carrier membrane, or other structure having a generally flat surface for supporting the reservoir 104. The reservoir 104 can be a separate component placed on the platform 106 (e.g., manually or via a robotic arm), or it can be an integral part of the platform 106. The platform 106 can be configured to cause the reservoir 104 to move along one or more directions D (… Figure 1B The movement direction D is relative to the energy source 108 to form a continuous portion of the additively manufactured object, as further described below. In the illustrated embodiment, the movement direction D is along the X-axis of the system 100, while in other embodiments, the movement direction D may be along different directions. Alternatively or in combination, the energy source 108 may be moved relative to the storage device 104 using, for example, a motor, conveyor belt, moving table, robotic arm, etc.

[0104] Energy sources 108 are configured to output energy (e.g., via polymerization and / or other bonding reactions as described herein) that cures the curable material 102. Each energy source 108 can independently output any suitable type of energy, such as electromagnetic energy (e.g., infrared, visible, UV, microwave), acoustic energy, and / or radiative energy (e.g., alpha radiation, beta radiation, neutron radiation). For example, energy sources 108 can be light sources that each generate one or more wavelengths of light, such as lasers, LEDs, broadband light sources (e.g., lamps), etc. In embodiments where a single energy source 108 outputs multiple wavelengths of light, multiple wavelengths can be generated using optical elements (such as beam combiners, dichroic mirrors, holographic elements, asymmetric lenses and / or mirrors, wavelength-changing light sources, broadband light sources combined with filters, or suitable combinations thereof). As described herein, wavelengths can be selected to trigger chemical reactions within the curable material 102. Some or all of the energy sources 108 can output the same type of energy (e.g., energy with the same wavelength), or some or all of the energy sources 108 can output different types of energy (e.g., energy with different wavelengths). Although the illustrated embodiment shows two energy sources 108a, 108b, in other embodiments, system 100 may include any suitable number of energy sources 108, such as three, four, five or more energy sources 108, as further described below.

[0105] The energy generated by energy source 108 can be in the form of an energy beam 110. For example, energy beam 110 can be a monochromatic and / or coherent beam. Although energy beam 110 is depicted as having a constant diameter, in other embodiments, part or all of energy beam 110 may alternatively be a converging or diverging beam with a variable diameter, as discussed further below. Energy beam 110 can have any suitable beam shape, such as circular, elliptical, square, rectangular, etc. Optionally, energy source 108 may include optical elements (e.g., mirrors, lenses, prisms, filters, beam splitters) to control the direction and / or characteristics (e.g., wavelength, phase, intensity, diameter, shape) of the corresponding energy beam 110.

[0106] The energy source 108 can be positioned above the reservoir 104 to direct the energy beam 110 downwards through the opening 116 and into the curable material 102. The energy source 108 can be located at the same height (e.g., Z position) above the reservoir 104, or at a different height above the reservoir 104. Figure 1A As best viewed from the center, the energy source 108 can be arranged as a linear array in the YZ plane of the system 100 (for illustrative purposes only, the energy source 108 is shown in the diagram). Figure 1B (The image is depicted as slightly offset in the X and Z directions). The energy sources 108 can be spaced apart from each other by any suitable distance along the Y-axis, such as distances in the range of 0.5cm to 1cm, 1cm to 2cm, 2cm to 5cm, 5cm to 10cm, or 10cm to 20cm, and / or greater than 20cm. The distance between the energy sources 108 can be determined based on the size of the object being printed, the desired resolution of the printed object, the size of the reservoir 104 and / or platform 106, and / or other relevant considerations. For example, the distance between adjacent energy sources 108 can be equal to the total width (Y dimension) of the reservoir 104 divided by the number of energy sources 108. However, in other embodiments, the energy sources 108 can be arranged differently, as further described below.

[0107] like Figure 1AAs best seen, each energy source 108 can be configured to have its corresponding energy beam 110 scan through the curable material 102. For example, a first energy source 108a can cause a first energy beam 110a to scan through a first scanning region 118a, while a second energy source 108b can cause a second energy beam 110b to scan through a second scanning region 118b. Each scanning region 118 can be a 2D shape of a plane passing through the volume of the curable material 102. Depending on the position and configuration of the energy sources 108, the scanning regions 118 can be located in the same plane or can be located in different planes. For example, in the illustrated embodiment, the energy beam 110 sweeps along the Y-axis in the YZ plane of the system 100 such that the scanning region 118 is located in the YZ plane and orthogonal to the X-axis of the system 100 (which may be the direction of movement D of the reservoir 104). However, in other embodiments, one or more of the scanning regions 118 may alternatively be at an angle relative to the X-axis, such as at least 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°, 100°, 110°, 120°, 130°, 140°, 150°, 160°, or 170°.

[0108] For example, such as Figure 1A As shown, the scanning region 118 can be a fan-shaped region generated by sweeping each energy beam 110 along a corresponding arc. In other words, each energy source 108 can independently rotate its corresponding energy beam 110 relative to the curable material 102 within a certain angular range. The rotation angular range can be at least 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°, 100°, 110°, 120°, 130°, 140°, 150°, 160°, 170°, or 180°. In some embodiments, the angular range is 10° to 90°, 90° to 120°, or 120° to 180°. Alternatively or in combination, the scanning region 118 can be generated by other techniques, such as by translating the energy beam 110 (e.g., along the X and / or Z directions).

[0109] During the additive manufacturing process, each energy beam 110 scans its respective scan region 118 multiple times to form continuous portions (e.g., sections, slices, and / or layers) of the additively manufactured object. Each energy beam 110 can scan its respective scan region 118 at any suitable rate (also referred to as "sweep rate" or "scan rate"). For example, the sweep rate of the energy beam 110 can be at least 1 rad / s, 180 rad / s, 1800 rad / s, or 18,000 rad / s. Alternatively or in combination, the sweep rate can be at least 100 Hz, 200 Hz, 500 Hz, 1 kHz, 2 kHz, or 5 kHz.

[0110] Energy source 108 can be configured in many different ways to allow scanning of energy beam 110. In some embodiments, some or all of the energy source 108 directs its respective energy beam 110 onto an optical element that moves (e.g., rotates and / or translates) to allow the energy beam 110 to scan through a corresponding scanning area 118. For example, the optical element can be a rotating optical element, such as a rotating mirror, rotating lens, or rotating prism. The rotating optical element can be a polygonal structure (e.g., a multifaceted mirror) with multiple facets that receive and direct the energy beam 110 toward the curable material 102, such as three, four, five, six, seven, eight, nine, ten, or more facets. As the polygonal structure rotates, the energy beam 110 can be deflected continuously along the length of each facet. At any given time, one of the facets can receive and deflect the energy beam 110 toward the curable material 102. As the facets change their rotational position due to the rotation of the polygonal structure, the angle of incidence of the energy beam 110 relative to the facets changes, thereby changing the deflection angle and thus the angle of the energy beam 110 relative to the curable material 102, causing the energy beam 110 to scan along an arc through the scanning region 118. Therefore, the sweep length and rate of the energy beam 110 can depend on the facet length and rotation rate of the polygonal structure. In some embodiments, the polygonal structure rotates in a single direction (e.g., clockwise or counterclockwise) such that the energy beam 110 always scans in a single direction (e.g., from left to right along the Y-axis, or from right to left along the Y-axis). In other embodiments, the rotating polygonal structure can rotate in multiple directions (e.g., clockwise and counterclockwise) to allow the energy beam 110 to scan in multiple directions (e.g., back and forth along the Y-axis).

[0111] Alternatively or in combination, other methods, such as galvanometer motor scanner systems or other energy guiding systems, and / or by movement of energy source 108 relative to curable material 102, may be used to scan energy beam 110. For example, some or all of energy source 108 may be rotated (e.g., about the X-axis and / or Y-axis) and / or translated (e.g., along the X-axis and / or Z-axis) to cause the corresponding energy beam 110 to scan through curable material 102. Each energy source 108 may be independently movable, or energy source 108 may be part of a single movable component.

[0112] In some embodiments, energy source 108 is or includes a laser source that generates a laser beam. Alternatively, a single laser source can be used as energy source 108, and multiple laser beams can be generated using optical elements (e.g., beam splitters, prisms, holographic elements). One or more movable optical elements (e.g., rotating multifaceted mirrors) as described herein can be used to scan the laser beams. Optionally, the laser beams can have a coherence length that allows for the generation of a stable interference pattern when the laser beams intersect. The stable interference pattern can be spatially and phase-stable enough to allow the curable material 102 to be cured in a manner that records the interference pattern in space. Recording of the interference pattern can occur through a higher reaction rate of the curable material 102 in the constructive interference region than in the destructive interference region. In some embodiments, the recorded interference pattern is detected as a change in refractive index by forming a grating and / or by forming a hologram. The use of two or more laser beams as described herein can provide the ability to control the shape, pattern, size, and / or orientation of the interference pattern (also known as “multibeam holography”). This method can be used in embodiments where the curable material 102 can form gratings and / or regions with different material properties. For example, the curable material 102 can be a resin used for volumetric holographic printing. As another example, the curable material 102 can include any material described in U.S. Patent No. 11,434,316, the disclosure of which is incorporated herein by reference in its entirety.

[0113] In some embodiments, the energy source 108 is or includes an LED, which may be a single LED unit or part of a larger LED array. One or more movable optical elements, such as those described herein (e.g., rotating faceted mirrors), can be used to scan the light beam from the LED. Optionally, an optical system (e.g., a lens and / or mirror system) can be used to guide the light from the LED at various angles relative to the curable material 102 (e.g., in the X and / or Y directions). In some embodiments, the LED is part of a rotating LED array (such as a cylindrical array, where LEDs are arranged on the outer surface of a cylinder and facing outwards). The rotating LED array can be rotated about one or more axes (such as the X and / or Y axes of system 100) to scan the light beam. Optionally, multiple rotating LED arrays can be used individually or in combination with other types of light sources.

[0114] In some embodiments, the energy source 108 is or includes a broadband light source. One or more filters (e.g., a turn-on filter, a cut-off filter, a band-pass filter, a dichroic filter) can be used to modify the light generated by the broadband light source. Any of the techniques described herein can be used to make the light generated by the broadband light source scan through the curable material 102.

[0115] In some embodiments, the energy source 108 is or includes a digital micromirror device (DMD). Light from a light source (e.g., a laser) can be directed onto the DMD, and individual mirrors of the DMD can be individually controlled to generate a beam. In some embodiments, the light has a coherence length suitable for producing an interference pattern in the curable material 102, which can be recorded by reactive chemical properties, as described elsewhere herein.

[0116] The scanning regions 118 generated by the energy source 108 can overlap each other at one or more locations. For example, as Figure 1A As shown, the first scanning region 118a overlaps with the second scanning region 118b at the overlapping region 120, such that both the first energy beam 110a and the second energy beam 110b can reach positions within the overlapping region 120. The size and position of the overlapping region 120 can be determined based on various parameters such as the position of the energy source 108, the size of the energy beam 110, the shape of the energy beam 110, the direction of movement of the energy beam 110 (e.g., rotation direction), and / or the range of movement of the energy beam 110 (e.g., angular range). Optionally, the first scanning region 118a may include a non-overlapping region 122a, which can be approached by the first energy beam 110a but not by the second energy beam 110b; and / or the second scanning region 118b may include a non-overlapping region 122b, which can be approached by the second energy beam 110b but not by the first energy beam 110a.

[0117] In some embodiments, the curable material 102 is configured to solidify when the energy dose received at a specific location (e.g., a voxel) within the curable material 102 is greater than or equal to a threshold dose. The energy dose received at a location may be a function of the intensity of the energy received at that location and the exposure time. Applying an energy dose greater than or equal to the threshold dose can cause the curable material 102 to solidify (e.g., polymerize) beyond its gel point, thereby solidifying the curable material 102 at that location. Applying an energy dose less than the threshold dose may not cause the curable material 102 to solidify, or may cause some solidification but not enough to exceed its gel point, leaving the curable material 102 in a liquid state. Therefore, solidification of the curable material 102 occurs when the combined energy dose delivered by the energy source 108 is greater than or equal to the threshold dose used to solidify the curable material 102; while if the combined energy dose delivered by the energy source 108 is less than the threshold dose, the curable material 102 can remain liquid.

[0118] In some embodiments, the curable material 102 can only solidify at a specific location if both energy sources 108 deliver sufficient energy to that location; otherwise, the curable material 102 may not solidify at that location if energy is delivered to that location by a single energy source 108 and / or insufficient energy is delivered to that location by both energy sources 108. In other words, depending on the intensity and / or exposure time of each energy source 108, the maximum energy dose generated by a single energy source 108 may be less than the threshold dose required to solidify the curable material 102, while the combined energy dose generated by the two energy sources 108 may be greater than or equal to the threshold dose.

[0119] Figure 2 This is a partial schematic diagram illustrating the selective solidification of a curable material 102 using multiple energy beams 110 according to an embodiment of the present technology. The curable material 102 can be divided into multiple voxels 202. Figure 2 As shown, the energy beam 110 can simultaneously apply energy to voxel 202a to deliver a combined energy dose greater than or equal to a threshold dose for solidifying the curable material 102, thereby causing the curable material 102 to solidify at voxel 202a. In contrast, voxels 202 that receive energy only from a single energy beam 110 (e.g., voxel 202b) or voxels 202 that do not receive any energy (e.g., voxel 202c) can remain unsolidified.

[0120] Figure 3A and Figure 3B This is a partial schematic diagram illustrating the selective consolidation of a curable material 102 using multiple energy beams 110 according to an embodiment of the present technology. The curable material 102 can be divided into multiple voxels 302. In the illustrated embodiment, the energy beams 110 can sequentially apply energy to voxels 302a, wherein a first energy beam 110a applies energy to voxels 302a for a first time period (…). Figure 3A Subsequently, the second energy beam 110b applied energy to voxel 302a for a second duration ( Figure 3B During the first and second time periods, the combined energy dose delivered by energy beam 110 to voxel 302a can be greater than or equal to a threshold dose for solidifying the curable material 102, thereby causing the curable material 102 to become a solid cured material at voxel 302a. In contrast, voxels 302 that receive energy only from one of the energy beams (e.g., voxels 302b, 302c) or that do not receive any energy can remain uncured.

[0121] Refer again Figure 1A and Figure 1BAn additively manufactured object can be formed from the curable material 102 by selectively consolidating it using an energy beam 110. Specifically, since the overlapping region 120 corresponds to the location where the energy beam 110 can deliver a combined dose of energy to consolidate the curable material 102, the object can be formed within the overlapping region 120. Furthermore, as each energy beam 110 sweeps across its corresponding scanning region 118, the curable material 102 can be selectively consolidated only at certain locations within the overlapping region 120 corresponding to the desired object geometry by controlling the scanning parameters of the energy beam 110. The scanning parameters can include one or more of the following: whether the energy beam 110 is on or off, the intensity of the energy beam 110, and / or the sweep rate of the energy beam 110 (which can affect the exposure time generated by the energy beam 110). The scanning parameters can be varied for different locations of the energy beam 110 within the scanning region 118. For example, the energy beam 110 can be turned off when the energy beam 110 is in one corner position and turned on when the energy beam 110 is in another corner position; when the energy beam 110 is in one corner position, the energy beam 110 can have a first intensity, and when the energy beam 110 is in another corner position, the energy beam 110 can have a different second intensity; and so on.

[0122] For example, Figure 4A and Figure 4B These are schematic front and side cross-sectional views of a system 100 during an operational phase for forming an additively manufactured object 150, according to embodiments of the present technology. The object 150 can be formed by selectively consolidating one or more locations (referred to herein as "object locations") within the curable material 102 that correspond to the geometry of a specific portion (e.g., cross-section) of the object 150 using an energy beam 110. To consolidate the curable material 102 at an object location, scanning parameters of the energy source 108 can be controlled such that the energy source 108 applies a sufficiently high combined energy dose to the object location, for example, by simultaneously or sequentially applying energy to the same location. Conversely, to prevent the curable material 102 from consolidating at a location that is not an object location, scanning parameters of the energy source 108 can be controlled such that one or both energy beams 110 are turned off as they pass through the location, or such that if both energy beams 110 are turned on as they pass through the location, the combined energy dose delivered to the location by the energy beams 110 is below a threshold dose (e.g., due to insufficient total energy intensity and / or insufficient total exposure time).

[0123] like Figure 4B As the energy beam 110 repeatedly scans through its respective scanning region 118 (e.g., as...), the best view is achieved. Figure 1AAs depicted in [the illustration], the reservoir 104 can advance relative to the energy source 108 along the direction of movement D1, thereby forming a continuous portion 152 of the object 150. For example, in the illustrated embodiment, the scanning region 118 is located in the YZ plane of the system 100, such that the object portion 152 is a YZ section continuously formed from left to right as the reservoir 104 moves to the left along the X-axis. The movement of the reservoir 104 (e.g., the speed and / or direction of movement) can be coordinated with the scanning of the energy beam 110, such that the YZ section of the object 150 is formed at an appropriate position along the X-axis to construct the desired 3D shape of the object 150.

[0124] Next reference Figure 4C and Figure 4D These are schematic front and side cross-sectional views of system 100 during subsequent operational phases for forming object 150. The process of scanning energy beam 110 and propulsion reservoir 104 can be repeated until the entire object geometry has been formed. Object 150 can then be removed from reservoir 104 for further processing.

[0125] Figures 1A to 4D The operation of system 100 can be controlled by a controller (not shown) operatively coupled to various components of system 100 (e.g., energy source 108, reservoir 104, platform 106, and / or any temperature control element). The controller may be or include a computing device comprising one or more processors and a memory storing instructions for performing the operations described herein. For example, the controller may control the scanning parameters of energy source 108 and the movement of reservoir 104 to selectively solidify curable material 102, thereby forming object 150 from a plurality of consecutive portions 152, as described herein. As another example, the controller may control heating and / or cooling generated by one or more temperature control elements to adjust the temperature of curable material 102.

[0126] In some embodiments, the controller uses a set of manufacturing instructions specifying scanning parameters of the energy source 108 to control the operation of the system 100. The manufacturing instructions may also specify the moving speed and / or direction of the reservoir 104 to form one or more additively manufactured objects, or may assume that the moving speed and / or direction is constant. The manufacturing instructions can be generated using software algorithms, which may be implemented by the controller, a separate computing device (e.g., the computing device of a treatment planning system), or a combination thereof. Additional details of the software algorithms that can be used are provided below.

[0127] It can be modified in many ways Figures 1A to 4DThe configuration of system 100 shown is illustrated. For example, the configuration of one or more components of system 100 can be changed. In some embodiments, one or more of the energy sources 108 may be part of the reservoir 104 and / or platform 106, rather than separate from these components. One or more energy sources 108 may be configured to direct energy through the sidewall 114 of the reservoir 104, in which case the sidewall 114 may be made of an optically transparent material. Alternatively or in combination, one or more energy sources 108 may be configured to direct energy through the platform 106 and the bottom wall 112 of the container, in which case the platform 106 and the bottom wall 112 may be made of an optically transparent material. Optionally, system 100 may include at least one energy source 108 (e.g., a lamp) that irradiates a larger area instead of outputting a focused beam. Such an energy source 108 can be used to uniformly cure one or more segments of the curable material 102, which can be used to increase the degree of curing of any object portion within these segments beyond the gel point of the curable material 102.

[0128] System 100 may include Figures 1A to 4D Additional components not shown. In some embodiments, reservoir 104 includes a liner covering the inner surfaces of the bottom wall 112 and / or side walls 114, which can be removed from reservoir 104. The liner can be used to transport the curable material 102 and / or additively manufactured objects to another location for additional processing, such as filtering the curable material 102 to remove the objects. The liner may include a cover window near the opening 116 of reservoir 104 to form a closed volume. Optionally, the liner may include one or more ports to allow the introduction and / or removal of the curable material 102. The liner can be made of any suitable material, such as plastic, glass, ceramic, wood, or metal. The liner can be transparent, translucent, or opaque to energy from energy source 108.

[0129] In some embodiments, system 100 includes components configured to cure a curable material 102 at a selected location via triple fusion upconversion. Triple fusion upconversion can use high-intensity light (e.g., red light) to generate annihilator triplet states, which combine to release higher-energy photons (e.g., blue photons). These emitted photons can then cure the curable material 102 in a small area. This process can achieve very high dimensional accuracy during volumetric additive manufacturing (VAM), and when combined with the upconversion technique described herein, even greater accuracy and faster printing can be achieved by curing large volumes using standard VAM and then using upconversion to cure more detailed areas. Alternatively, the upconversion technique can be used to cure the entire object at a slower rate. In some embodiments, the upconversion technique uses two photoinitiators that are sensitive to either the initial high-intensity light or the emitted higher-energy wavelength, respectively. For example, a first (e.g., high-intensity) photoinitiator may include one or more sensitizers and triplet annihilation agents, while a second (e.g., higher-energy) photoinitiator may include a Norrish 1-type photoinitiator with moderate to strong absorbance at higher-energy upconverted photons (e.g., 1 to 1,000 (very low), 1,000 to 10,000 (low), 10,000 to 30,000 (medium), 30,000 to 50,000 (strong), 50,000 and greater (very strong) molar absorbance units). In some embodiments, the higher the extinction coefficient of the higher-energy photoinitiator, the greater the degree of localization of the upconverted photon emission source that the curing can maintain, thereby improving resolution. Similar hybrid systems can be combined to produce similar high-resolution VAM printing, such as photoactivation inhibitors, photoactivation blockers (e.g., photochromic agents), two-photon absorption, etc. This hybrid approach can be used to cure surfaces of objects where the dose differences between two adjacent voxels may be very similar, thus potentially adversely affecting resolution. Using a hybrid system, the internal volume of an object can be cured using the dose accumulation technique described herein via a known VAM process, while surfaces or segments requiring higher resolution can be cured using upconversion photonics and other two-photon techniques (e.g., sequential or simultaneous photonics).

[0130] In some embodiments, higher resolution can be achieved using two different wavelengths of light and a photoinitiator system, for example, as in orthogonal lithography. Orthogonal lithography processes can use photo-switching photoinitiators to induce localized polymerization within a volume of photosensitive material when linearly excited by crossing beams of different wavelengths. In some embodiments, two or more wavelengths of light are used to achieve two different chemical reactions (e.g., radical and cationic polymerization, or other orthogonal chemical reactions), which allows for spatial control of material properties (e.g., generating interpenetrating polymer networks (IPNs), polymerization-induced phase separation, and / or others).

[0131] Furthermore, some components of system 100 may be omitted. For example, although the illustrated embodiment depicts the curable material 102 as contained within reservoir 104, in embodiments where the curable material 102 is highly viscous and exhibits little or no flow after deposition, reservoir 104 may be omitted, and the curable material 102 may be deposited directly onto platform 106. Therefore, any embodiment described herein in connection with the curable material 102 within reservoir 104 can be applied to curable material 102 positioned directly on platform 106.

[0132] In some embodiments, instead of using energy source 108 to cure the curable material 102, a reverse process can be used, wherein the starting material is already in a partially or fully cured state, and energy source 108 selectively degrades, liquefies, or otherwise reverses the curing of the cured material. Examples of materials that can be used in this method include degradable polymers and degradable oligomers. For example, the material may be or includes a vitrifier. As another example, the material may be or includes a polyacetal. In some embodiments, energy causes a change in the cured material that allows selected portions of the cured material to liquefy and be removed in a post-processing step (e.g., via solvent dissolution, melting, mechanical treatment, ultrasonic treatment). Some non-limiting examples of chemical processes that can be used to degrade polymers and / or oligomers (e.g., including vitrifiers) are through thermal depolymerization (e.g., low upper temperature polymers), reverse photodimerization reactions, photo-cleavage of bonds, and / or activation by photo-acids, bases, or other catalysts, which then lead to bond breakage. Other techniques (e.g., phase transitions from a crystalline phase to an amorphous phase) may be used alternatively or additionally to separate the cured object from the remaining material. For example, heat can be selectively absorbed into sections of the curable material 102 that are not part of the object, and the crystalline object can be separated from the amorphous uncured material if the time for recrystallization during melting is short or prevented (e.g., by forming a eutectic mixture).

[0133] Figures 5A to 9CVarious features of an additive manufacturing system configured according to embodiments of the present technology are shown. Figures 5A to 9C Any features of the embodiments can be combined with each other and / or incorporated into Figures 1A to 4D In system 100. Furthermore, combined with... Figures 5A to 9C The system described can be broadly similar to Figures 1A to 4D System 100 allows similar numbers (e.g., energy source 108 and energy source 508) to be used to identify similar or identical components, and Figures 5A to 9C The following discussion will be limited to combinations Figures 1A to 4D The features that differ from those in the described embodiments.

[0134] Figures 5A to 5C An additive manufacturing system with various energy source arrangements according to embodiments of the present technology is illustrated. For example, Figure 5A This is a partial schematic front cross-sectional view of an additive manufacturing system 500a comprising three energy sources 508a–508c (collectively referred to as “energy sources 508”). Specifically, system 500a includes: a first energy source 508a configured to scan a first energy beam 510a through a first scanning region 518a; a second energy source 508b configured to scan a second energy beam 510b through a second scanning region 518b; and a third energy source 508c configured to scan a third energy beam 510c through a third scanning region 518c. Energy sources 508 can be any energy source described herein, such as a laser, LED, broadband light source, etc.

[0135] Energy sources 508 may be positioned above reservoir 104 to direct their respective energy beams 510a-510c (collectively, “energy beams 510”) into curable material 102. Some or all of the energy sources 508 may be at the same height (e.g., Z-position), or some or all of the energy sources 508 may be at different heights. In some embodiments, the energy sources 508 are arranged as an array within the same YZ plane of system 500a. The energy sources 508 may be distributed along the Y-axis of system 500a.

[0136] The scanning regions 518a-518c (collectively referred to as "scanning regions 518") generated by energy source 508 can be 2D shapes located in respective planes. For example, in the illustrated embodiment, scanning regions 518 are fan-shaped regions generated by sweeping energy beam 510 across corresponding arcs. Depending on the position and configuration of energy source 508, some or all of the scanning regions 518 may be located in the same plane (e.g., the same YZ plane), or some or all of the scanning regions 518 may be located in different planes (e.g., different YZ planes). Furthermore, some or all of the scanning regions 518 may have the same angular range, or some or all of the scanning regions 518 may have different angular ranges.

[0137] The scan regions 518 may overlap each other at one or more overlapping locations. For example, as shown... Figure 5A As shown, the first scan region 518a, the second scan region 518b, and the third scan region 518c may overlap each other at the overlapping region 524a; the first scan region 518a and the third scan region 518c may overlap each other at the overlapping regions 524b and 524c; the first scan region 518a and the second scan region 518b may overlap each other at the overlapping region 524c; and the second scan region 518b and the third scan region 518c may overlap each other at the overlapping region 524e. Part or all of the scan regions 518 may also include non-overlapping regions that cannot be approached by other energy sources 508.

[0138] As described herein, the curable material 102 can be cured when a combined energy dose applied to a specific location (e.g., a voxel) within the curable material 102 is greater than or equal to a threshold dose. The threshold dose can be achieved by simultaneously or sequentially applying energy to a location within the curable material 102 using multiple energy sources 508. In some embodiments, the threshold dose can be achieved using at least two energy sources 508, allowing an object portion to be formed in any of the overlapping regions 524a-524e. Alternatively, the threshold dose can be achieved using only all three energy sources 508, allowing an object portion to be formed only in the overlapping region 524a.

[0139] although Figures 1A to 4D and Figure 5AThe systems described herein are respectively depicted as including two and three energy sources, but the technology can be adapted to include any suitable number of energy sources, such as four, five, six, seven, eight, nine, ten, or more. The energy sources can be arranged in any suitable configuration to create intersecting scan regions at one or more overlapping regions within the curable material, thereby allowing selective consolidation of the curable material within the overlapping regions by simultaneously or sequentially delivering energy to selected locations using two or more energy beams. Any embodiments herein can be modified such that at least two, three, four, five, or more energy sources are required to deliver a threshold energy dose; and / or such that no more than five, four, three, or two energy sources are required to deliver a threshold energy dose. In some cases, a greater number of energy sources can provide a wider range of locations within the curable material that can be individually “addressed” with a specified energy dose, and / or can provide greater flexibility because a variety of different combinations of energy sources can be used to deliver energy to specific locations. In some embodiments, only one energy source is required or used to provide the energy for curing one or more voxels, such as in the case of using multiple reflective elements and / or in the case of combining other technologies with this technology (such as photon upconversion and / or photodegradation) and / or in the case of a given object having a portion that can be fully cured by only one energy source.

[0140] Figure 5B This is a partially schematic side view of an additive manufacturing system 500b with angled energy sources 508d and 508e according to an embodiment of the present technology. System 500b includes a first energy source 508d that outputs a first energy beam 510d and a second energy source 508e that outputs a second energy beam 510e. Figure 5B As shown, energy beams 510d and 510e are angled, such that the corresponding scanning areas of energy beams 510d and 510e are also angled relative to the X-axis of system 500b, rather than being located in the same YZ plane. For example, the scanning area of ​​energy beam 510d can be at an acute angle A1 relative to the X-axis, for example, angle A1 can be less than 90° and / or less than or equal to 80°, 70°, 60°, 50°, 40°, 30°, 20° or 10°. The scanning area of ​​energy beam 510e can be at an obtuse angle A2 relative to the X-axis, for example, angle A2 can be greater than 90° and / or greater than or equal to 100°, 110°, 120°, 130°, 140°, 150°, 160° or 170°. In the illustrated embodiment, the scanning areas of energy sources 508d and 508e are located in different planes; however, in other embodiments, energy sources 508d and 508e can be configured to output energy beams 510d and 510e at the same angle, such that the scanning areas are located in the same plane.

[0141] The system described herein can be adapted to include any suitable number of energy sources, each capable of independently generating a scanning area at any suitable angle relative to the X-axis (e.g., 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, 90°, 100°, 110°, 120°, 130°, 140°, 150°, 160°, or 170°). Some or all of the scanning area can be at the same angle, or some or all of the scanning area can be at different angles. Using scanning areas at different angles allows for a wider range of addressable locations within the curable material.

[0142] Figure 5C This is a partial schematic side view of an additive manufacturing system 500c with offset energy sources 508f and 508g according to an embodiment of the present technology. System 500c includes a first energy source 508f that outputs a first energy beam 510f and a second energy source 508g that outputs a second energy beam 510g. Figure 5C As shown, energy sources 508f and 508g are located at different positions along the X-axis of system 500c. For example, energy sources 508f and 508g can be spaced apart by distances ranging from 0.5cm to 1cm, 1cm to 2cm, 2cm to 5cm, 5cm to 10cm, or 10cm to 20cm. Therefore, the scanning areas generated by energy sources 508f and 508g can also be spaced apart and located in different planes. Although Figure 5C The scan area is depicted at different angles relative to the X-axis, but in other embodiments, the scan area may be at the same angle relative to the X-axis (which may be a right angle, an acute angle, or an obtuse angle, as described herein).

[0143] The system described herein can be adapted to include any suitable number of energy sources, some or all of which may be located at the same position along the X-axis of the system, or some or all of which may be located at different positions along the X-axis of the system. Furthermore, some or all of the energy sources may be located at the same position along the Y-axis of the system, or some or all of which may be located at different positions along the Y-axis of the system. For example, the system may include an array of energy sources located in the XY plane of the system, such as a square array, rectangular array, circular array, or any other suitable array shape. Additionally, some or all of the energy sources may be located at the same position along the Z-axis of the system, or some or all of which may be located at different positions along the Z-axis of the system. Generally, the system described herein may include any suitable spatial arrangement of energy sources relative to the curable material.

[0144] Figure 6A and Figure 6BDifferent beam shapes that can be produced by an energy source of an additive manufacturing system according to embodiments of the present technology are shown. For example, Figure 6A This is a partial schematic diagram of an energy beam 610a with a constant diameter along its length (e.g., the energy beam 610a may be a collimated beam). In some embodiments, for a given amount of rotation about the rotation axis R, the area swept by the energy beam 610a increases with increasing distance from the rotation axis R, thereby creating a fan-shaped scanning region. Therefore, in embodiments where the rotation axis R is positioned above the curable material 102, voxels located at higher Z positions can be larger than voxels located at lower Z positions. In other words, the energy dose delivered by the energy beam 610a can diffuse over a larger volume at a deeper location within the curable material 102. This effect can be further enhanced when using an energy beam with a divergence diameter (where the beam size increases with distance from the rotation axis R).

[0145] In some embodiments, when determining appropriate scanning parameters, the software algorithm considers the different energy doses delivered to voxels at different Z positions within the curable material 102. Alternatively or in combination, the difference in energy doses can be reduced by positioning the axis of rotation further away from the surface of the curable material 102. In this embodiment, it may be advantageous to use multiple other energy sources spaced further apart from each other to reduce voxel size and / or improve the ability to irradiate a given voxel independently of adjacent voxels through overlapping scanning regions.

[0146] Figure 6B This is a partial schematic diagram of an energy beam 610b with a converging diameter, where the beam size decreases with distance from the rotation axis R. In some embodiments, the converging shape of the energy beam 610b causes the intensity to increase with increasing distance from the rotation axis R, but this increase in intensity can be balanced by increasing the sweep area. Therefore, the energy beam 610b can deliver the same or substantially the same energy dose to different Z positions within the curable material 102.

[0147] Figure 7 This is a partial schematic front cross-sectional view of an additive manufacturing system 700 configured according to an embodiment of the present technology. The system 700 includes a curable material 702 in a reservoir 704 on a platform 706, and a plurality of energy sources 708 that output corresponding energy beams 710.

[0148] The reservoir 704 includes a bottom wall 712 and multiple side walls 714. For example... Figure 7As shown, the sidewalls 714 are angled outwards to conform to the shape of the scanning area 718 generated by the energy source 708. For example, the inner surface of the sidewalls 714 can be aligned with the outer boundary of the scanning area 718. For example, the angle between the bottom wall 712 and each sidewall 714 can be at least 90°, 100°, 110°, 120°, 130°, 140°, 150°, 160°, or 170°. Therefore, the reservoir 704 can have a trapezoidal cross-sectional shape, wherein the upper part of the reservoir 704 is wider than the lower part of the reservoir 704. This configuration is advantageous for reducing the volume of the curable material 702 used by the system 700, because curable material 702 located outside the scanning area 718 may not be accessible to the energy source 708 and therefore may not be usable for forming objects.

[0149] Figures 8A to 8C An additive manufacturing system with optical elements for redirecting energy is illustrated according to an embodiment of the present technology. The optical elements may be reflective elements, refractive elements, or suitable combinations thereof. Using optical elements to redirect energy beams can be used to increase the range of locations within a curable material that can be accessed by the energy beam. In some embodiments, the optical elements effectively generate new “energy sources” by redirecting the energy beam, making it possible to use fewer energy sources, or even a single energy source.

[0150] For example, Figure 8A This is a partial schematic front cross-sectional view of an additive manufacturing system 800a, which includes a reflective element 830 (e.g., a mirror) for deflecting an energy beam 810 generated by an energy source 808. The reflective element 830 may have a fixed position and orientation, or it may be adjustable (e.g., translational and / or rotational) to control the direction of the deflected energy beam 810. In the illustrated embodiment, the reflective element 830 is a separate component spaced apart from the reservoir 804a. For example, the reflective element 830 may be positioned above and to one side of the reservoir 804a. However, in other embodiments, the reflective element 830 may be positioned at different locations within the system 800a, such as above the central portion of the reservoir 804a. In other embodiments, the reflective element 830 may be attached to the reservoir 804a and / or a portion of the reservoir 804a (e.g., above the level of the curable material 802). Alternatively, the reflective element 830 may be located below the reservoir 804a and / or the platform 806. Furthermore, despite Figure 8A A single reflective element 830 is shown, but system 800a may alternatively include additional reflective elements 830, such as two, three, four, five or more reflective elements 830.

[0151] Figure 8BThis is a partial schematic front cross-sectional view of an additive manufacturing system 800b, which includes a reservoir 804b having a reflective element 832 (e.g., a mirror) for deflecting an energy beam 810 generated by an energy source 808. The reflective element 832 may have a fixed position and orientation, or it may be adjustable (e.g., translational and / or rotational) to control the direction of the deflected energy beam 810. In the illustrated embodiment, the reflective element 832 is embedded within a sidewall 834 of the reservoir 804b. Alternatively, the reflective element 832 may be positioned at another portion of the reservoir 804b, such as on the surface of the sidewall 834, within the bottom wall 836, or on the surface of the bottom wall 836. The portion of reservoir 804b containing the reflective element 832 may be optically transparent to the energy beam 810 and / or may be matched to the refractive index of the curable material 802 to reduce refraction. Optionally, other portions or even the entire reservoir 804b may be optically transparent and / or matched to the refractive index of the curable material 802. Furthermore, although... Figure 8B A single reflective element 832 is shown, but the reservoir 804b may alternatively include additional reflective elements 832, such as two, three, four, five or more reflective elements 832.

[0152] Figure 8C This is a partial schematic front cross-sectional view of an additive manufacturing system 800c, in which a reservoir 804c serves as a reflective element for deflecting an energy beam 810 generated by an energy source 808. In the illustrated embodiment, the reservoir 804c includes a sidewall 838 that redirects the energy beam 810 via total internal reflection. For example, the surface in the sidewall 838 that receives the incident energy beam 810 may be made of, coated with, or otherwise comprised of a material that generates total internal reflection of the energy beam 810. In other embodiments, other portions of the reservoir 804c, such as the bottom wall 840 of the reservoir 804c, may alternatively or additionally be configured as reflective elements. The portion of the reservoir 804c that receives the incident and / or deflected energy beam 810 may be optically transparent to the energy beam 810 and / or have its refractive index matched to that of a curable material 802 to reduce refraction. Alternatively, other portions of the reservoir 804b may be optically transparent and / or have a refractive index that matches that of the curable material 802.

[0153] Figure 8D This is a partial schematic front cross-sectional view of an additive manufacturing system 800d, which includes a reservoir 804d having an array of reflective elements 850 (e.g., mirrors) for deflecting an energy beam 810 generated by an energy source 808. The reflective elements 850 may be arranged in a 2D array (e.g., a grid) consisting of multiple rows and columns. Although in Figure 8DSix reflective elements 850 are visible in the diagram, but system 800d may include any suitable number of reflective elements 850, such as 10, 15, 20, 25, 30, 40, 50, or more. Some or all of the reflective elements 850 may have fixed positions and orientations, or some or all of the reflective elements 850 may be adjustable (e.g., translational and / or rotational) to control the direction of the deflected energy beam 810. In the illustrated embodiment, the reflective elements 850 are configured as an array formed on the surface of the sidewall 852 of the reservoir 804d. Alternatively or in combination, system 800d may include reflective elements 850 at other portions of the reservoir 804d, such as within the sidewall 852, on the bottom wall 854 of the reservoir 804d, or within the surface of the bottom wall 854 of the reservoir 804d. Optionally, the reflective element 850 may be present on or within the two side walls 852 of the reservoir 804d, and / or on or within the bottom wall 854 of the reservoir 804d.

[0154] Figures 9A to 9C Various cured patterns that can be used to form additively manufactured objects according to embodiments of the present technology are shown. For example, Figure 9A This is a cross-sectional view of the cured pattern 900a, in which all curable materials 902 within object 950a have solidified (e.g., solidified above the gel point of curable materials 902), while all curable materials 902 outside object 950a remain unsolidified (e.g., not yet solidified above the gel point of curable materials 902). In some embodiments, curable materials 902 adjacent to the surface of object 950a may be more solidified than curable materials 902 further away from object 950a, but may still be below the gel point of curable materials 902.

[0155] Figure 9B This is a cross-sectional view of the cured pattern 900b, in which the shell 954 corresponding to the surface of the object 950b is cured, but the curable material 902 inside the object 950b remains uncured. The curable material 902 outside the object 950b may also remain uncured. Optionally, the curable material 902 inside the object 950b may be cured in a separate curing process, such as curing using different chemical reactions and / or post-curing after an additive manufacturing process.

[0156] Figure 9C This is a cross-sectional view of the cured pattern 900c, in which some curable material 902 on the exterior of object 950c is cured, but the shell 956 surrounding the surface of object 950c within the curable material 902 remains uncured. Object 950c can be as follows: Figure 9C The surface shown may be completely solidified, or only the surface of object 950c may be solidified (e.g., similar to...). Figure 9B Object 950b).

[0157] A manufacturing instruction set can be used to control the additive manufacturing system disclosed herein, specifying how various system components (e.g., energy sources, platforms) should be operated to produce a desired object geometry. Manufacturing instructions can be generated using software algorithms. Input data for the software algorithm can include a digital representation of the object's geometry, such as a 3D digital model (e.g., a surface model, mesh model, parametric model, etc.). Optionally, input data can include system parameters indicating a specific configuration of the system, such as the location of the energy source, characteristics of the energy source (e.g., beam shape, beam size, wavelength, intensity, sweep rate, angular range, on / off rate), the size and shape of the reservoir, the reservoir's movement speed, the reservoir's movement direction, the layer thickness of the curable material, the type of curable material, characteristics of the curable material (e.g., the threshold dose for curing the curable material, the curable material's permeation and / or absorption of energy), and / or the location and characteristics of any present reflective elements (e.g., size, location, orientation, whether the reflective element is fixed or adjustable). Input data can be retrieved from a database, manually entered by a human operator, determined from simulation and / or experimental data, or obtained from one or more sensors, machine vision, or a suitable combination thereof. The output data of the software algorithm can be a digital dataset indicating scanning parameters of the energy source (and optionally, the movement of the reservoir and / or the orientation of an adjustable light reflector) to produce the geometry of the object.

[0158] Software algorithms can be implemented in many different ways. For example, for each voxel within a curable material, the software algorithm can determine the appropriate energy dose (e.g., energy intensity and exposure time) to be delivered to the voxel to either solidify the curable material at that voxel or prevent it from solidifying. The software algorithm can then determine how each energy source should be controlled to deliver the appropriate dose to each location. For example, the software algorithm can determine a set of scan parameters for each energy source to generate an energy dose at that voxel. In some embodiments, for each energy beam sweeping across its corresponding scan area at a specific X location within the curable material each time, the scan parameter set includes the timing (“activation mode”) at which the energy beam should be turned on and off during the sweep to deliver the appropriate energy dose to each voxel within the scan area.

[0159] In some embodiments, the voxel size used by the software algorithm is defined based on the overlap of the beam diameter (e.g., the X and / or Y dimensions) and / or the beam diameters from each energy source (e.g., no overlap occurs in each voxel during each X-dimensional translation of the reservoir). For example, for a circular Gaussian beam, the beam diameter may be defined as the full width at half maximum intensity of the beam. Optionally, the curing kinetics of the curable material, such as the diffusion rate of reactive and / or inhibitory substances, reactive diffusion, the Tromsdorff-Norrish effect, exothermic and / or endothermic effects on the reaction rate, photoinitiator bleaching, light absorption from the initiator and / or other components, etc., may also be considered when determining the voxel size.

[0160] Furthermore, the translation of the reservoir in the X-axis (“X-translation”) does not need to be in units of integer multiples of the beam width, but can be in units of fractions of the beam width (e.g., 1 / 10 or half the beam diameter). In some embodiments, the X-translation is continuous rather than performed in discrete units. In such embodiments, the scan time can be faster than the X-translation, allowing a complete sweep of the X-dimensional segment through the curable material to occur before a significant movement of the reservoir in the X direction occurs. For example, if the reservoir is translated in the X direction at a rate of 1 mm / s, the sweep rate makes it take 0.001 seconds for the energy beam to complete a sweep through the YZ plane, and the beam diameter is 0.10 mm, then the X-translation during exposure is 0.001 mm, which is 1% of the beam diameter. Thus, five complete sweeps can occur before a 5% change in the beam diameter, a change small enough to still be counted as a single beam diameter unit if an X-based unit approach is used for the voxels. Depending on the desired X-dimensional resolution, for a given voxel, a larger or smaller translational drift can occur in the X direction, such as less than 1%, 2%, or 10%, and / or up to 100%. In some embodiments, translational drifts of less than 10%, 5%, 2%, 1%, 0.1%, or 0.01% are used.

[0161] In some embodiments, the sweep rate of part or all of the energy source is the same as the movement rate of the reservoir (e.g., the X-translation rate). Alternatively, the sweep rate can be at least 2, 5, 10, 100, or 1000 times the movement rate. The sweep rate of the energy source can be independent of the on / off rate of the energy source, such that the energy source can be turned on and off to generate individual energy arcs during a given sweep through the scanned region. The smallest useful arc can be an arc capable of generating a voxel of one bundle diameter at the deepest segment of the curable material layer. Thus, the energy source can be configured to turn on and off at a rate faster than the sweep rate. Therefore, the voxel size in the YZ plane can be controlled by the sweep rate and the on / off rate of the energy source.

[0162] The software algorithm can also consider the dosage to be delivered to one or more voxels adjacent to the target voxel and can determine whether any curing or consolidation of the adjacent voxels will occur. In some embodiments, for voxels adjacent to a consolidating voxel, the threshold dosage for consolidation is reduced because the Tromsdorff-Norrish effect at the voxel, the reduced inhibitor concentration, and / or the increased viscosity can decrease the termination rate and / or increase the overall polymerization rate. In embodiments where the curable material comprises multiple different resins, the software algorithm can consider the individual characteristics of each resin (e.g., dosage requirements).

[0163] In some embodiments, the software algorithm determines an energy dosage to produce curing of the curable material well above its gel point in a controlled manner. In conventional VAM systems, objects are typically cured up to their gel point, which can result in low green strength and may make the object difficult to handle and / or clean. Typically, objects may be damaged during removal from the curable material (e.g., particularly for viscous resins) or when cleaning the green state object using solvents or mechanical techniques. Curing the object well above its gel point can increase the object's green strength. In some embodiments, the software algorithm is configured to produce a fully cured region within and / or on the surface of the object. This region can be a mesh, support, shell, and / or solid region. In some embodiments, the algorithm maximizes curing at the surface and / or interior of the object while maximizing under-curing of voxels adjacent to the object's surface. Optionally, the algorithm may ignore regions remote from the object surface by, for example, implementing a custom loss function in the optimization.

[0164] In some embodiments, a software algorithm generates a gradient of energy dose within a curable material, which can be used to produce spatial variations of one or more properties of the cured material, such as modulus, transparency, color, impact resistance, yield elongation, elongation at break, solubility in a solvent, density, melting point, percentage of crystallinity, etc. This method (also known as “graying”) can directly induce specific property results in the material using the applied energy dose. Graying can be used to spatially define regions within an additively manufactured object that have specific material properties dependent solely on the energy dose received during the additive manufacturing process, or material properties that may depend primarily on the energy dose received during the additive manufacturing process and have further dependencies, such as various post-processing factors (e.g., time, solvent cleaning, heating, exposure, addition of wet chemical modifications). Additional examples and details of graying techniques that can be incorporated into this art are provided in U.S. Patent Application No. 18 / 449,589, the disclosure of which is incorporated herein by reference in its entirety.

[0165] Furthermore, compared to conventional VAM algorithms that consider only two potential curing levels (e.g., consolidated and unconsolidated) when determining energy dosage (which results in weak printed objects), the software algorithm disclosed herein can consider three or more different curing levels to optimize energy dosage. The curing level can be quantified based on the percentage of curing relative to the gel point of the material and the maximum possible percentage of curing of the material, for example, curing level = (%curing - %curing at the gel point) / (maximum possible %curing - %curing at the gel point) × 100%. Therefore, the amount of “over-curing” can be defined, for example, from 0% over-curing (curing level equal to the % curing that achieves gelation) to 100% (curing level is the maximum possible % curing). Thus, when optimizing energy dosage, curing levels such as 5%, 10%, 20%, or more over-curing can be used for selected voxels and / or regions. Alternatively or in combination, the curing level can be quantified based on the green strength of the material relative to the green strength of the cured material at the gel point, such that "over-curing" occurs when the green strength of the cured material exceeds the green strength of the material at the gel point (e.g., 20%, 50%, 100%, 200%, or 1000% greater than the green strength at the gel point), as measured using dynamic mechanical analysis, tensile testing, rheological testing, etc. For example, the structural "skeleton" of an object can be selected to have a high curing level (e.g., close to 100% over-curing) to provide high strength, thereby allowing for physical processing of the printed parts during post-processing, while other parts of the object can have a lower curing level.

[0166] In some embodiments, the software algorithm defines critical areas of the object. In some cases, the printed object does not need to be 100% accurate across all parts; instead, there may be parts requiring high accuracy and others where lower accuracy is acceptable. For example, in embodiments where the object is a dental appliance with a housing (which has multiple cavities for receiving and repositioning teeth), the inner surfaces of the cavities may require a higher degree of accuracy, while the outer surfaces of the housing may be less accurate. Therefore, the inner surfaces can be fabricated at the full resolution of the system, while the outer surfaces can be fabricated at a lower resolution. The resolution can be defined based on the range of voxels at the surface of interest of the object, for example, a high-resolution region within + / -1 voxels of the designed surface geometry, while a low-resolution region may be within + / -2 voxels, + / -3 voxels, + / -4 voxels, + / -5 voxels, etc. Optionally, upper and lower limits can be set; for example, the object may have an over-cured range exceeding 5 voxels on its outer surface, but an under-cured range (e.g., the material has not yet reached the gel point) less than 2 voxels on its inner surface. Therefore, software algorithms can optimize the printing accuracy of the parts of an object that require printing accuracy, thus arriving at a solution faster than algorithms that optimize the entire object to achieve the highest level of accuracy.

[0167] Representative examples of parameters that the software algorithm disclosed herein may consider and / or use include: beam shape, sweep rate, dwell time at each angle, energy intensity, energy wavelength, on / off switching rate, time for the energy source to be fully on, time for the energy source to be fully off, time for changing the direction of the energy beam, time for changing the sweep rate of the energy beam, the moving speed of the reservoir, the moving direction of the reservoir, the angle at which energy (e.g., light) is incident on the curable material, the reactivity of the curable material, the temperature of the curable material, the energy absorption characteristics of the curable material, the viscosity of the curable material, the concentration of chemicals in the curable material (e.g., monomers and other reactive substances, inhibitors, photoinitiators and other catalysts, photoblockers), the diffusion rate of chemicals in the curable material, and the position and orientation of the reflective element. Other information that can be used to improve the quality and accuracy of printed objects includes the desired degree of curing (e.g., grayscale) of a given voxel, the dose received by adjacent voxels, the position of voxels next to interfaces (e.g., liner, reservoir, air, wall, inserted parts), the time delay between energy doses, scattering in the curable material, shadow areas produced by other parts in the curable material, and refraction / reflection caused by other parts in the curable material.

[0168] In some embodiments, the software algorithm uses only one or more of the following parameters to determine the appropriate dose for each voxel: beam shape, sweep rate, residence time, energy intensity, energy wavelength, on / off switching rate, time for the energy source to be fully on, time for the energy source to be fully off, time for changing the direction of the energy beam, time for changing the sweep rate of the energy beam, reactivity of the curable material, temperature of the curable material, energy absorption characteristics of the curable material, viscosity of the curable material, and / or position and orientation of the reflective element.

[0169] Figure 10A This is a flowchart illustrating a method 1000 for determining scanning parameters for manufacturing an additively manufactured object according to an embodiment of the present technology. Method 1000 can be used to generate parameters for any system and apparatus described herein (such as...). Figures 1A to 9C Manufacturing instructions (for any embodiment of the method). In some embodiments, some or all of the processes of method 1000 are implemented as computer-readable instructions (e.g., program code) configured to be executed by one or more processors of a computing device.

[0170] Method 1000 may begin at box 1010 by receiving a 3D digital representation of the object to be manufactured. The 3D digital representation may be any digital dataset representing the geometry of the object, such as a 3D digital model (e.g., a surface model, a mesh model, a parametric model, etc.).

[0171] At block 1020, method 1000 may continue by generating multiple 2D cross-sections from a 3D digital representation. As disclosed herein, the 2D cross-sections may correspond to multiple portions (e.g., slices and / or layers of the object) of an object to be formed using an additive manufacturing system with scanning energy sources. For example, the 2D cross-sections may be multiple YZ planes of the object truncated at consecutive positions along the X-axis of the object, where each YZ plane corresponds to a single sweep of the energy source through its corresponding scanning region in the YZ plane of the system. Optionally, the process at block 1020 may also include discretizing the object geometry into multiple voxels. The voxel dimensions may correspond to the minimum resolution of the additive manufacturing system and may be determined based on the beam diameter of the energy source, the overlap of the beam diameters of the energy sources, the sweep rate of the energy sources, the translation rate of the reservoir, and / or translational drift, as discussed above.

[0172] At block 1030, method 1000 may include determining scanning parameters of a plurality of energy sources to form a plurality of 2D cross sections by a curable material. This can be done according to any embodiment described herein (e.g., in conjunction with...). Figures 1A to 9C Multiple energy sources can be configured. For example, the energy sources can be configured to output multiple corresponding energy beams scanning through multiple corresponding scanning regions in a curable material, wherein the scanning regions overlap each other at one or more locations to allow the energy beams to deliver energy to these locations simultaneously or sequentially. In some embodiments, the energy source is a light source (e.g., a laser, LED) that generates a beam of light (e.g., a laser beam) scanning through the curable material. The curable material can be a resin comprising one or more polymerizable components that solidify upon exposure to a threshold energy dose. The curable material can be housed within a reservoir that advances relative to the energy source as the energy source scans through it. Optionally, one or more reflective elements can be positioned on, within, and / or near the reservoir to deflect the energy beam.

[0173] Scanning parameters can be configured to selectively solidify the curable material at one or more object locations within a 2D cross-section, while leaving it unconsolidated at one or more locations not part of the 2D cross-section. Specifically, scanning parameters can be configured to deliver a combined energy dose from the energy source to the object location exceeding a threshold dose for solidification, while delivering a combined energy dose to other locations not exceeding the threshold dose. Scanning parameters can be or include any adjustable parameters of the additive manufacturing system that affect the characteristics and / or spatial distribution of the energy generated by one or more energy sources. For example, scanning parameters can include any of the following: the energy intensity of one or more energy sources (e.g., energy intensity over time, energy intensity of the energy beam from the energy source at each angle), the activation mode of one or more energy sources, the sweep rate of one or more energy sources, the residence time of one or more energy sources at each angle, the beam shape of one or more energy sources, the location of one or more energy sources, and / or the location and orientation of one or more reflective elements (if present).

[0174] In some embodiments, a software model is used to determine scanning parameters that predict the energy dose to be delivered to each location in the curable material for a specific set of scanning parameters, and thus predict the corresponding object geometry to be formed. The predictions generated by the software model can be used in an optimization process to determine the set of scanning parameters, thereby producing an energy dose distribution that achieves the desired object geometry. For example, in embodiments where the energy is light energy, the model can be a light field prediction model that calculates the global light dose distribution over the curable material, thereby predicting the locations where the curable material will be cured by light energy and not. The light field prediction model can be used as part of an optimization process to calculate the scanning parameters of the light sources that achieve the desired global light dose distribution, thereby forming a 2D cross-section of the object with sufficient accuracy. In some embodiments, the light field prediction model is used to optimize one or more of the following: the light intensity produced by each light source at each time point and / or at each angle of the beam; the dwell time of the beam at each angle; the scanning speed of the beam over time; the beam shape; the number of light sources used; the location of the light sources; and / or the orientation and position of reflective elements (if any).

[0175] For example, Figure 10B A method 1030a for determining scan parameters using a predictive model, according to an embodiment of the present technology, is illustrated. According to an embodiment of the present technology, method 1030a can be used as… Figure 10A It is part of the process in box 1030 to be executed.

[0176] Method 1030a may begin at block 1032 with setting initial values ​​for the scan parameters of the energy source. The initial values ​​may be randomized values, preset values, user-provided values, or a suitable combination thereof. In some embodiments, the initial values ​​are estimates of the optimal values ​​for the scan parameters. These estimates may be based on scan parameters used for other objects with similar geometries, experimental data, user input, etc.

[0177] At box 1034, method 1030a may include generating a predicted object geometry formed by multiple energy sources using scanning parameters. The predicted geometry can be generated using a software model that determines the energy dose delivered to each location in the curable material based on initial values ​​of the scanning parameters. The energy dose can then be used to assess whether the curable material will be cured or remain uncured at each location (e.g., by comparing the energy dose to a threshold dose), thereby predicting the object geometry to be formed.

[0178] The model can generate predictions using any suitable technique, such as simulation (e.g., ray-tracing-based methods), mathematical computation (e.g., analytical expressions), machine learning algorithms, rule-based algorithms, or suitable combinations thereof. For example, a ray-tracing-based method could involve generating multiple rays representing an energy beam produced by an energy source, determining the path of each ray through the curable material, and then calculating the energy dose delivered to each voxel of the curable material based on the paths of all rays. Each energy source can be represented by a corresponding set of rays at different angles (e.g., corresponding to the angle swept by the energy beam output from the energy source). Each ray can be associated with an intensity value, e.g., corresponding to the energy intensity and / or activation mode of the energy beam at each angle determined by scanning parameters. The number of rays used in the calculation can be chosen to provide sufficiently high accuracy while maintaining computational efficiency. For example, the scanned area of ​​the energy source can be represented by at least 20, 50, 100, 200, 500, or 1000 rays. Ray-based methods may be advantageous for modeling systems with more complex geometries and / or movable parts.

[0179] Optionally, energy dose calculations may also take into account the interaction of the radiation with the curable material and / or other components, such as reflection of the radiation from the walls of the reservoir and / or any reflective elements present, and absorption of the radiation by the curable material. Other effects and / or material properties that may be considered in the calculations include diffraction, refraction, viscosity, thermal accumulation, reactivity, diffusion, the Trommsdorff-Norrish effect, exothermic and / or endothermic effects, and bleaching. In some embodiments, the effects of the radiation may be calculated based on the total cumulative effect on a particular voxel (e.g., when curing is based on the total cumulative energy dose), based on the instantaneous effect on a particular voxel (e.g., when curing is based on the instantaneous energy intensity at each time (such as for upconversion)), or a suitable combination thereof. A representative example of energy dose predictions generated using a ray-tracing-based method is provided in Example 1 below.

[0180] As another example, mathematical methods can involve deriving analytical expressions for the energy dose within the curable material. These analytical expressions can then be evaluated at each voxel to calculate the energy dose at that voxel for a given set of scan parameters. For instance, if the positions of the energy source, the voxels of the curable material, and the planar reflector are all fixed, the angle at which the energy beam emitted from the energy source is reflected from the reflector to the voxel position can be derived from geometric principles and the position of each component. Therefore, geometric functions can be used to determine which energy beams will reach each voxel, which can then be used to calculate the dose delivered to each voxel. In some cases, the evaluation of analytical expressions can be faster than other techniques and can allow calculations to be performed at arbitrary locations throughout the computational domain.

[0181] Optionally, the prediction can be based on one or more system parameters of the additive manufacturing system. System parameters can specify characteristics of various components of the additive manufacturing system, such as the configuration of the energy source (e.g., position, beam shape, sweep rate, on / off switching rate, time to full on / off, time to change direction, time to change sweep rate), the configuration of the reservoir (e.g., size, shape, movement speed, movement direction), the properties of the curable material (e.g., reactivity, temperature, energy absorption characteristics, viscosity), and / or the configuration of any reflective elements that may be present (e.g., position, size, shape, adjustability). System parameters differ from scan parameters in that system parameters can represent fixed, unchangeable characteristics of the additive manufacturing system, while scan parameters can represent adjustable, optimizable characteristics of the additive manufacturing system. For example, in some embodiments, the prediction may assume that the position, sweep rate, and beam shape of the energy source are fixed, but the energy intensity and activation mode of the energy source are adjustable. Alternatively, the prediction may assume that the position, sweep rate, and / or beam shape are also adjustable. Alternatively, if a reflective element is used, the position and orientation of the reflective element can be fixed or adjustable, depending on the configuration of the additive manufacturing system.

[0182] At box 1036, method 1030a may continue by comparing the predicted geometry of the object with at least one of a plurality of 2D cross-sections of the object. The 2D cross-sections may represent the target geometry of the object, while the predicted object geometry may be an estimate or simulation of the actual geometry that would be formed using scan parameters. The comparison may involve, for example, evaluating the similarity between a portion or all of the 2D cross-sections and the predicted geometry of one or more object portions (e.g., one or more slices and / or layers of the object) by calculating the error (e.g., a distance-based error) between each 2D cross-section and the predicted geometry of the corresponding object portion.

[0183] At block 1038, method 1030a may optionally include modifying the values ​​of the scan parameters based on the comparison results. For example, if the comparison results indicate that the predicted object geometry is not sufficiently similar to the 2D cross-section (e.g., the error exceeds a threshold), one or more of the scan parameters may be modified to improve the similarity (e.g., by reducing the error). Method 1030a may then return to block 1034 to generate an updated prediction of the object geometry using the modified values ​​of the scan parameters, and then return to block 1036 to compare the updated prediction with the 2D cross-section. The processes of blocks 1034, 1036, and 1038 may be repeated until values ​​of the scan parameters that provide a sufficient degree of similarity between the predicted object geometry and the target object geometry (e.g., values ​​that result in a reduction or minimum error) are obtained. In some embodiments, the processes of blocks 1034, 1036, and 1038 are performed as part of an optimization procedure, and optimization methods known to those skilled in the art (e.g., gradient descent) are used to determine the modifications to the scan parameters.

[0184] Refer again Figure 10A After determining the scanning parameters, method 1000 can proceed to block 1040, where instructions are generated for manufacturing an object using multiple energy sources with the scanning parameters. For example, the instructions can control the operation of the additive manufacturing system so that the energy sources scan their corresponding energy beams through the curable material according to the determined scanning parameters.

[0185] It can be modified in many different ways Figure 10A and Figure 10B The methods shown. For example, although described regarding a single object Figure 10A and Figure 10B The methods described above, however, can be used to determine scan parameters for manufacturing any suitable number of objects (such as dozens, hundreds, or thousands). As another example, the scan parameters can be changed... Figure 10A and Figure 10B The order of the processes shown. Some processes of the method can be omitted (e.g., Figure 10A The process (and / or method) of boxes 1020 and / or 1040 may include Figure 10A and Figure 10B Additional processes not shown in the diagram.

[0186] Figure 11 This is a schematic block diagram illustrating a workflow 1100 for determining the energy intensity for manufacturing an additively manufactured object according to an embodiment of the present technology. Workflow 1100 can be used to determine the energy intensity of any system and apparatus described herein (such as...). Figures 1A to 9C The energy intensity of the energy source (in any embodiment). Workflow 1100 can be used with any method described herein (such as...). Figure 10A Method 1000 and / or Figure 10B Method 1030a) is performed in combination. In some embodiments, part or all of the process of workflow 1100 is implemented as computer-readable instructions (e.g., program code) configured to be executed by one or more processors of a computing device.

[0187] Workflow 1100 may include receiving a 3D digital model of an object to be manufactured (e.g., a dental appliance) (box 1102). The 3D digital model may then be sliced ​​into multiple 2D sections (e.g., a vertical (YZ) plane), which may be used as input to an optimization algorithm (box 1106) for determining the energy intensity required to manufacture the object using an additive manufacturing system with a scanning energy source as described herein.

[0188] In some embodiments, the input to the optimization algorithm includes an initial set of energy intensities of energy sources (box 1108), such as the laser intensities of multiple laser sources. Each energy source may have multiple initial energy intensity values ​​that vary over time for the corresponding energy beam, and / or multiple initial energy intensity values ​​for each angle swept by the energy beam in the scanning area of ​​the energy source. For example, in some embodiments, the scanning area of ​​the energy source is discretized into at least 20, 50, 100, 200, 500, or 1000 different angles, and an initial energy intensity value is set for each angle. The initial energy intensity values ​​may be randomized values, preset values, estimates of optimized values, values ​​input by the user, etc.

[0189] Optionally, the input to the optimization algorithm may include one or more system parameters (box 1110). As described herein, system parameters may represent fixed characteristics of an additive manufacturing system with an energy source. For example, system parameters may include physical printer parameters, such as the location of the energy source (e.g., laser location) and / or the location of reflective elements. Alternatively or in combination, the input to the optimization algorithm may include any other type of system parameters described herein.

[0190] The optimization algorithm may include calculating the global energy dose delivered to the curable material (box 1112). A software prediction model can be used to generate the global energy dose, determining the energy dose delivered to each voxel of the curable material based on the initial energy intensity and system parameters. The prediction model may use ray-tracing-based methods, analytical expressions, machine learning algorithms, rule-based algorithms, and / or any other techniques described herein. Optionally, the energy dose can then be used to assess whether the curable material will be cured or will remain uncured at each location (e.g., by comparing the energy dose to a threshold dose), thereby predicting the geometry of the object to be formed.

[0191] The optimization algorithm then compares the calculated global energy dose with the target geometry of the object (box 1114). The target geometry can be a 2D cross-section of the object. In some embodiments, the output of the global energy dose calculation is a series of 2D digital representations (e.g., 2D images) representing the predicted energy dose of the energy source each time it sweeps across the curable material, and each 2D digital representation is compared with a corresponding 2D cross-section of the object. The comparison can involve evaluating the similarity between each 2D digital representation and the corresponding 2D cross-section, such as by calculating the error between each 2D digital representation and the corresponding 2D cross-section.

[0192] Based on the comparison results, the optimization algorithm can modify part or all of the energy intensity of the energy source (box 1116). For example, modifications may include increasing the energy intensity value at a specific time point / angle, decreasing the energy intensity value at a specific time point / angle, setting the energy intensity value at a specific time point / angle to zero, etc. Modifications can be configured to increase the similarity between the global energy dose and the target geometry and / or decrease the error between the global energy dose and the target geometry. In some embodiments, gradient descent and / or other optimization methods known to those skilled in the art are used to determine the modifications.

[0193] In some embodiments, the optimization algorithm involves repeatedly calculating the energy dose, comparing the dose with the target geometry, and modifying the energy intensity until a satisfactory energy intensity value is obtained (e.g., a value that maximizes the similarity between the global energy dose and the target geometry and / or minimizes the error between the global energy dose and the target geometry). These values ​​can then be used as the final energy intensity for generating manufacturing instructions for the additive manufacturing system (box 1118).

[0194] Although workflow 1100 is shown and described with respect to energy intensity optimization, in other embodiments, workflow 1100 may alternatively or additionally be used to optimize the values ​​of any other type of scan parameters described herein.

[0195] Figure 12 This is a flowchart illustrating a method 1200 for manufacturing an additively manufactured object according to an embodiment of the present technology. Method 1200 can be performed by any system and apparatus described herein (such as...). Figures 1A to 9C The method 1200 can be performed in any embodiment thereof. In some embodiments, part or all of the process of method 1200 is implemented as computer-readable instructions (e.g., program code) configured to be executed by one or more processors (such as a controller) of a computing device. Figures 10A to 11 (The implementation examples) are combined and executed.

[0196] Method 1200 may begin at frame 1210 with the formation of a portion of an additively manufactured object from a curable material. For example, the additively manufactured object may be a dental appliance, such as an orthodontic appliance, palatal expander, retainer, accessory placement device, oral protector, etc. As described herein, the curable material may be disposed within a reservoir and / or on a movable platform. The curable material may be a resin comprising one or more polymerizable components (e.g., monomers, oligomers, reactive polymers) that polymerize upon exposure to energy or otherwise undergo a bonding reaction as described above.

[0197] The process in box 1210 may include scanning a first energy beam from a first energy source through a first scanning region in the curable material (box 1212) and scanning a second energy beam from a second energy source through a second scanning region in the curable material (box 1214). For example, the first and second energy sources may be light sources that generate corresponding beams (e.g., lasers, LEDs). Scanning of the first and second energy beams may be performed using any suitable technique, such as rotating optics, galvanometer-motor scanning systems, or other energy guiding systems, and / or by moving the first and second energy sources relative to the curable material. Scanning of the first and second energy beams may be performed simultaneously or sequentially.

[0198] As described herein, the first and second scanning regions can be 2D regions within the curable material generated by sweeping corresponding energy beams across multiple different angles. The first and second scanning regions can be located in the same plane or in different planes. In some embodiments, the first and second scanning regions are orthogonal to the direction of movement of the reservoir (e.g., the X-direction), while in other embodiments, the first and / or second scanning regions may be at another angle relative to the direction of movement of the reservoir. The first and second scanning regions may overlap each other at one or more locations to define an overlapping region. As described herein, the overlapping region can be a set of voxels within the curable material that can be irradiated simultaneously or sequentially by both the first and second energy beams.

[0199] The process in box 1210 may further include selectively solidifying the curable material (box 1216) to form a portion of the additively manufactured object. In some embodiments, the curable material is selectively solidified by delivering a combined energy dose to one or more object locations within the curable material using a first energy beam and a second energy beam, such that the combined energy dose is greater than or equal to a threshold dose (e.g., exceeding the gel point of the curable material) used to solidify the curable material. One or more object locations may be located within an overlap region of a first scan region and a second scan region, such that the first energy beam and the second energy beam can scan through the object locations simultaneously or sequentially to deliver the combined energy dose to the object locations. To prevent the curable material from solidifying at other locations within the overlap region, scanning parameters (e.g., activation mode, intensity, sweep rate) of the first energy beam and / or the second energy beam can be controlled during scanning such that the combined energy dose delivered to other locations is less than the threshold dose. Software algorithms can be used to determine appropriate scanning parameters, as described herein (e.g., in combination with...). Figures 10A to 11 ).

[0200] At block 1220, method 1200 may include advancing a curable material relative to a first energy source and a second energy source. For example, the curable material may be advanced by moving a reservoir containing the curable material using a movable platform, as described herein. The direction of movement may be orthogonal to the first and / or second scan regions, or may deviate from (e.g., not parallel to) the first and / or second scan regions. In some embodiments, the advancement of the curable material occurs simultaneously with the scanning of the first and / or second energy beams, while in other embodiments, the advancement of the curable material occurs sequentially with (e.g., before or after) the scanning of the first and / or second energy beams.

[0201] The process of boxes 1210 to 1220 can be repeated to form continuous parts of the additively manufactured object, thereby constructing the geometry of the 3D object from multiple 2D sections.

[0202] It can be modified in many different ways Figure 12 Method 1200 is shown. For example, although the above process of method 1200 is described with respect to a single object, method 1200 can be used to sequentially or simultaneously manufacture any suitable number of objects, such as dozens, hundreds, or thousands of additive manufacturing objects. As another example, the process can be modified... Figure 12 The sequence of processes shown. Some processes of method 1200 may be omitted and / or method 1200 may include... Figure 12Additional processes not shown. For example, method 1200 may involve forming a portion of an additive object by one or more additional energy sources. In this embodiment, the process at block 1210 may involve scanning a third energy beam from a third energy source through a third scan region such that a combined energy dose delivered to the object location by two or more of the first, second, and / or third energy sources exceeds a threshold dose; and so on.

[0203] Figure 13 This is a flowchart illustrating a method 1300 for manufacturing and processing an additively manufactured object according to an embodiment of the present technology. Method 1300 can be performed by any system and apparatus described herein (such as...). Figures 1A to 9C The method 1300 can be performed in any embodiment thereof. In some embodiments, part or all of the process of method 1300 is implemented as computer-readable instructions (e.g., program code) configured to be executed by one or more processors (such as a controller) of a computing device. Furthermore, method 1300 can be combined with any other method described herein (such as...). Figure 12 Method 1200) combination.

[0204] Method 1300 may begin at frame 1302 with the deposition of a curable material (e.g., a polymerizable resin) into a reservoir and / or platform. For example, the curable material may be deposited into a reservoir carried by a movable platform. Alternatively, the curable material may be deposited directly onto the movable platform (e.g., in an embodiment where the curable material is a high-viscosity resin that does not flow after deposition).

[0205] The curable material can be deposited as a substantially uniform layer into the reservoir. This layer can have any suitable thickness, such as within the range of 1 μm to 10 μm, 10 μm to 100 μm, 100 μm to 1 mm, 1 mm to 1 cm, or 1 cm to 10 cm, or it can be greater than 10 cm. In some embodiments, the layer thickness is greater than or equal to the height of the additively manufactured object to be formed, while in other embodiments, the layer thickness is less than the height of the object. The layer thickness can be greater than the voxel size of the object (e.g., the Z-dimensional voxel size). For example, the layer thickness can be at least 2, 3, 4, 5, 10, 20, 50, 100, or 1000 times the height of a single voxel (e.g., the Z-dimensional voxel). In such embodiments, the voxel size can be the smallest voxel size in the Z-dimensional that the system and the curable material can produce under printing conditions.

[0206] The deposition of curable materials can be performed using any suitable technique, such as using mechanical elements (e.g., doctor blades, wire rods), spin coating, dip coating, spraying (e.g., electrostatic spraying), solvent casting, liquid casting with flow and leveling, jetting (e.g., inkjet, compressed air jetting), extrusion (e.g., die extrusion, syringe extrusion, fused deposition modeling), casting, spreading of subsequently melted / fused powder, or suitable combinations thereof. In some embodiments, the curable material is introduced using reactive dispensing techniques (e.g., using a static mixer attachment or inkjet to react two materials during mixing). In some embodiments, the curable material is introduced using co-extrusion or side-by-side extrusion. In embodiments where the curable material comprises multiple components (e.g., multiple different resins), a first component (e.g., a first resin) can be introduced into a reservoir and / or platform, and then a second component (e.g., a second resin) can be introduced into one or more selected locations within and / or on the first component using a nozzle or needle.

[0207] At box 1304, method 1300 can continue by using multiple energy sources to form a portion of the additively manufactured object. The process at box 1304 can be based on... Figure 12 Method 1200 is used to execute this.

[0208] In some embodiments, the processes of blocks 1302 and 1304 are performed once to form the entire additively manufactured object. This method can be used in embodiments where the layer thickness of the curable material is greater than or equal to the maximum height of the object. However, in other embodiments, the processes of blocks 1302 and 1304 can be repeated to construct the additively manufactured object from a series of layers. This method can be used in embodiments where the layer thickness of the curable material is less than the maximum height of the object. For example, a first layer of curable material can be deposited and used to form the first layer of the object, then a second layer of curable material can be deposited and used to form the second layer of the object, and so on, until the entire object has been formed. Some or all of the object layers can be formed from the same curable material, or some or all of the object layers can be formed from different curable materials.

[0209] At box 1306, method 1300 may include separating the additively manufactured object from the curable material. The process at box 1306 may involve removing the object from the curable material (e.g., by lifting the object from a reservoir and / or removing it from a platform), removing the curable material from the object (e.g., by discharging the curable material from a reservoir and / or removing it from a platform), or a combination thereof.

[0210] In some embodiments, residual curable material is collected for reuse in subsequent additive manufacturing processes. Curable material already used in the additive manufacturing process may have partially cured or even solidified in some areas. Therefore, it may be advantageous to filter the curable material before reuse to remove any partially cured and / or solidified material, as well as any other debris and / or contaminants. Optionally, the curable material may be treated before reuse, such as by adding new curable material. One or more properties of the curable material can be monitored using techniques such as UV-Vis absorption, viscosity, cure depth measurement, optical differential scanning calorimetry, photorheology, Fourier transform infrared spectroscopy, etc., to ensure the consistency of the curable material (and thus the consistency of the object properties).

[0211] At box 1308, method 1300 may include performing one or more additional process steps (also referred to herein as “post-processing” of the additively manufactured object). In some embodiments, post-processing involves removing residual material from the additively manufactured object. Residual material may include unbonded curable material (e.g., liquid resin) and / or other unwanted material (e.g., debris) remaining on and / or inside the object after the additive manufacturing process. Residual material can be removed in many different ways, such as by applying mechanical force to the object (e.g., vibration, agitation, centrifugation, tumbling, brushing), exposing the object to a solvent (e.g., via spraying, immersion), heating or cooling the object, applying a vacuum to the object, blowing pressurized gas onto the object, and / or other suitable techniques.

[0212] In some embodiments, post-processing includes an additional curing step (“post-curing”). Post-curing can be used when the object remains in a partially cured “green” state after manufacturing. For example, the energy used to manufacture the object in frame 1304 may only partially cure (e.g., polymerize) the curable material forming the object. Therefore, a post-curing step may be needed to fully cure (e.g., fully polymerize) the object to its final usable state. Post-curing can provide various benefits, such as improved mechanical properties (e.g., stiffness, strength) and / or temperature stability of the object. Post-curing can be performed by heating the object, applying radiation (e.g., UV, visible light, microwaves), or a suitable combination thereof.

[0213] Optionally, post-processing may include modifying at least one surface of the additively manufactured object. Surface modification may be applied to some or all of the object's surfaces (e.g., external and / or internal surfaces) to alter one or more surface properties, such as surface finish (e.g., roughness, waviness, lay), porosity, visual appearance (e.g., gloss, transparency, visibility of printed lines), hydrophobicity, and / or chemical reactivity. In some embodiments, surface modification includes removing material from the object, for example, by polishing, milling, grinding, sandblasting, etc. Alternatively or in combination, surface modification may include applying additional material to the object. For example, the additional material may be a coating, such as a polymer coating. Coatings may be applied to one or more surfaces of the object for a variety of purposes, including but not limited to: providing a smooth surface finish, which may be aesthetically pleasing and / or improve user comfort if the object is intended to come into contact with a user's body (e.g., a dental appliance worn on teeth); coloring the object and / or applying other aesthetic features; improving scratch resistance and / or other mechanical properties; providing antimicrobial properties; and incorporating therapeutic agents into the object for controlled release. Examples of coating techniques that can be used include powder coating, dip coating, and vapor coating.

[0214] Other examples of post-processing that can be performed include, but are not limited to, additional cleaning of the object (e.g., washing with water, solvents, etc.); annealing of the object; trimming or otherwise separating the object from any substrates, supports, and / or other structures not intended to be present in the final product; and packaging the object for shipment.

[0215] It can be modified in many different ways Figure 13 Method 1300 is shown. For example, although the above process of method 1300 is described with respect to a single object, method 1300 can be used to sequentially or simultaneously manufacture any suitable number of objects, such as dozens, hundreds, or thousands of additive manufacturing objects. As another example, the process can be modified... Figure 13 The order of the processes shown is as follows. Some processes of method 1300, such as any processes in boxes 1302, 1306 and / or 1308, may be omitted.

[0216] Method 1300 may also include Figure 13Additional processes not shown. For example, a hybrid process involving at least one other additive manufacturing technology may be optionally used to manufacture the additively manufactured object. Examples of other additive manufacturing technologies that may be used in conjunction with this technology include any of the following: (1) vat photopolymerization, wherein an object is constructed from a vat or other volumetric source of liquid photopolymer resin, including technologies such as stereolithography (SLA), digital light processing (DLP), continuous liquid interface production (CLIP), two-photon induced photopolymerization (TPIP), and volumetric additive manufacturing (VAM); (2) material jetting, wherein material is jetted onto a build platform using a continuous or drop-on-demand (DOD) method; (3) binder jetting, wherein alternating layers of build material (e.g., powder-based material) and binder material (e.g., liquid binder) are deposited through a printhead; (4) material extrusion. The process involves: (5) material extraction through a nozzle, heating and being deposited layer by layer, such as fused deposition modeling (FDM) and direct ink writing (DIW); (6) powder bed fusion, including techniques such as direct metal laser sintering (DMLS), electron beam melting (EBM), selective thermal sintering (SHS), selective laser melting (SLM), and selective laser sintering (SLS); (7) sheet lamination, including techniques such as layered solid fabrication (LOM) and ultrasonic additive manufacturing (UAM); and (8) directional energy deposition, including techniques such as laser engineered net forming, directional light fabrication, direct metal deposition, and 3D laser cladding. In this embodiment, the first part of the object can be formed using the processes of blocks 1302 and 1304, and a second part of the object can be formed using another additive manufacturing technique. The second part can be formed before, simultaneously with, or after the formation of the first part of the object.

[0217] The various techniques described in this paper can be adapted to many different types of additive manufacturing modalities. For example, the process of selecting only portions of an object to optimize resolution and prioritizing the required resolution levels for different portions can be applied to other VAM methods, such as orthogonal lithography, computational axial lithography (CAL) volumetric printing, etc. As another example, selective overcuring of portions of an object to increase the green strength of the object is also applicable to many different additive manufacturing modalities. In another example, converging and diverging energy beams to change the resolution of lower voxels can be used in SLA and groove-based systems. In yet another example, additional mirrors and other reflective elements can be used in orthogonal lithography and CAL volumetric printing. In yet another example, holography or laser interferometry can also be used in other VAM methods. II. Dental instruments and related methods

[0218] Figure 14AA representative example of a tooth repositioning appliance 1400 configured according to embodiments of the present technology is shown. Appliance 1400 can be manufactured using any of the systems, methods, and apparatus described herein. Appliance 1400 (also referred to herein as an "orthodontic appliance") can be worn by a patient to achieve incremental repositioning of individual teeth 1402 in the jaw. Appliance 1400 may include a housing (e.g., a continuous polymer housing or a segmented housing) having a tooth-receiving cavity that accommodates and resiliently repositions the teeth. Appliance 1400 or portions thereof can be fabricated indirectly using a physical model of the teeth. For example, an appliance (e.g., a polymer appliance) can be formed using a physical model of the teeth and suitable polymer material sheets. In some embodiments, for example, a physical appliance is fabricated directly from a digital model of the appliance using additive manufacturing techniques.

[0219] The appliance 1400 can be adapted to all teeth present in the maxilla or mandible, or to fewer than all teeth. The appliance 1400 can be specifically designed to receive a patient's teeth (e.g., the morphology of the tooth receiving cavity matches the morphology of the patient's teeth) and can be manufactured based on a positive or negative mold of the patient's teeth generated by impression, scanning, etc. Alternatively, the appliance 1400 can be a general-purpose appliance configured to receive teeth, but not necessarily shaped to match the morphology of the patient's teeth. In some cases, only certain teeth received by the appliance 1400 are repositioned by the appliance 1400, while other teeth can provide a base or anchoring area to hold the appliance 1400 in place when the appliance 1400 applies force to one or more teeth that are the repositioning targets. In some cases, some, most, or even all teeth can be repositioned at some point during treatment. The moved teeth can also be used as a base or anchor for holding the appliance in place while the patient wears it. In a preferred embodiment, no thread or other means is provided for holding the appliance 1400 in proper position on the tooth. However, in some cases, it may be desirable or necessary to provide a separate attachment 1404 or other anchoring element on the tooth 1402, having a corresponding receiving portion 1406 or hole in the appliance 1400, so that the appliance 1400 can apply selected forces on the tooth. Representative examples of appliances, including those used in the Invisalign® system, are described in numerous patents and patent applications of Alain Technologies, Inc. (including, for example, U.S. Patent Nos. 6,450,807 and 5,975,893) and on the company’s website accessible on the World Wide Web (e.g., see link “invisalign.com”). Examples of attachments mounted on the teeth suitable for use with orthodontic appliances are also described in the patents and patent applications of Alain Technologies, Inc., including, for example, U.S. Patent Nos. 6,309,215 and 6,830,450.

[0220] Figure 14BA tooth repositioning system 1410 comprising multiple appliances 1412, 1414, 1416, according to an embodiment of the present technology, is illustrated. Any appliance described herein may be designed and / or provided as part of a group of multiple appliances for use in a tooth repositioning system. Each appliance may be configured such that the tooth receiving cavity has a geometry corresponding to an intermediate or final tooth arrangement intended for use with that appliance. By placing a series of incremental position adjustment appliances on a patient's teeth, the patient's teeth can be progressively repositioned from an initial tooth arrangement to a target tooth arrangement. For example, the tooth repositioning system 1410 may include: a first appliance 1412 corresponding to the initial tooth arrangement; one or more intermediate appliances 1414 corresponding to one or more intermediate arrangements; and a final appliance 1416 corresponding to the target arrangement. The target tooth arrangement may be the planned final tooth arrangement selected for the patient's teeth at the end of all planned orthodontic treatment. Alternatively, the target alignment can be one of several intermediate alignments used for the patient's teeth during orthodontic treatment, and can include a variety of different treatment scenarios, including but not limited to cases where surgery is recommended, where interproximal reduction (IPR) is appropriate, where progress checks are scheduled, where anchor placement is optimal, where palatal expansion is desired, and where restorative dentistry is involved (e.g., inlays, onlays, crowns, bridges, implants, veneers, etc.). Therefore, it should be understood that the target tooth alignment can be the result of any planned alignment of the patient's teeth following one or more incremental repositioning phases. Similarly, the initial tooth alignment can be any initial alignment of the patient's teeth followed by one or more incremental repositioning phases.

[0221] Figure 14CA method 1420 for orthodontic treatment using multiple appliances according to an embodiment of the present technology is illustrated. Method 1420 can be practiced using any of the appliances or groups of appliances described herein. In block 1422, a first orthodontic appliance is applied to the patient's teeth to reposition the teeth from a first dental alignment to a second dental alignment. In block 1424, a second orthodontic appliance is applied to the patient's teeth to reposition the teeth from the second dental alignment to a third dental alignment. Method 1420 can be repeated as needed using any suitable number of sequential appliances and combinations of sequential appliances to incrementally reposition the patient's teeth from an initial alignment to a target alignment. Appliances can be manufactured all at once, in groups, or in batches (e.g., at the beginning of a treatment phase), or appliances can be manufactured one at a time, and the patient can wear each appliance until pressure from each appliance on the teeth is no longer felt or until the maximum amount of expressed tooth movement for that given phase has been achieved. Multiple different appliances (e.g., a set) can be designed or even manufactured before the patient wears any of the appliances in the multiple appliances. After wearing an appliance for an appropriate period of time, the patient can replace the current appliance with the next appliance in the series until no more appliances are needed. Appliances are typically not fixed to the teeth, and the patient can place and change appliances at any time during the procedure (e.g., patient-removable appliances). The final appliance or multiple appliances in the series may have one or more geometries selected for overcorrecting tooth alignment. For example, one or more appliances may have geometries that will (if fully realized) move individual teeth beyond the alignment that has been selected as “final.” Such overcorrection may be desirable to counteract potential regression after the repositioning method has been terminated (e.g., allowing individual teeth to move back towards their pre-correction positions). Overcorrection can also be beneficial to accelerate the correction rate (e.g., an appliance with a geometry positioned beyond the desired intermediate or final position can move individual teeth toward that position at a greater rate). In this case, the use of the appliance can be terminated before the teeth reach the position defined by the appliance. Furthermore, overcorrection may be intentionally applied to compensate for any inaccuracies or limitations of the appliance.

[0222] Figure 15 A method 1500 for designing orthodontic appliances according to embodiments of the present technology is illustrated. Method 1500 can be applied to any embodiment of the orthodontic appliances described herein. Some or all of the steps of method 1500 can be performed by any suitable data processing system or apparatus (e.g., one or more processors configured with suitable instructions).

[0223] In box 1502, a movement path is determined to move one or more teeth from an initial alignment to a target alignment. The initial alignment can be determined, for example, using wax bite method, direct contact scanning, X-ray imaging, tomography, ultrasound imaging, and other techniques for obtaining information about the position and structure of teeth, jaws, gingiva, and other orthodontic-related tissues from a mold or scan of the patient's teeth or oral tissues. A digital dataset representing the initial (e.g., pre-treatment) alignment of the patient's teeth and other tissues can be obtained from the acquired data. Optionally, the initial digital dataset is processed to segment the tissue components to each other. For example, a data structure digitally representing the individual crowns can be generated. Advantageously, a digital model of the entire tooth can be generated, including the measured or inferred hidden surfaces and root structures, as well as the surrounding bone and soft tissue.

[0224] The target alignment of teeth (e.g., the desired and expected end result of orthodontic treatment) can be received from the clinician in the form of a prescription, calculated based on fundamental orthodontic principles, and / or inferred from the clinical prescription. By specifying the desired final position of the teeth and a digital representation of the teeth themselves, the final position and surface geometry of each tooth can be specified to form a complete model of the tooth alignment at the desired end of treatment.

[0225] Having both an initial position and a target position for each tooth, a movement path can be defined for the movement of each tooth. In some embodiments, the movement path is configured to move the tooth from its initial position to its desired target position in the fastest manner with the least amount of round trips. The tooth path can optionally be segmented (partitioned), and the segments can be computed such that the movement of each tooth within a segment remains within threshold limits for linear translation and rotational translation. In this way, the endpoints of each path segment can constitute a clinically feasible repositioning, and the set of segment endpoints can constitute a clinically feasible sequence of tooth positions such that moving from one point to the next in the sequence does not result in tooth collision.

[0226] In box 1504, a force system for generating movement of one or more teeth along the movement path is defined. The force system may include one or more forces and / or one or more torques. Different force systems can produce different types of tooth movement, such as tilting, translation, rotation, extrusion, intrusion, root movement, etc. Biomechanical principles, modeling techniques, force calculation / measurement techniques, etc. (including knowledge and methods commonly used in orthodontics) can be used to determine the appropriate force system to be applied to the teeth to achieve tooth movement. Sources may be considered when determining the force system to be applied, including literature, force systems determined through experimental or virtual modeling, computer-based modeling, clinical experience, minimization of unwanted forces, etc.

[0227] The determination of the force system can be performed in a variety of ways. For example, in some embodiments, the force system is determined on a patient-by-patient basis, such as using patient-specific data. Alternatively or in combination, the force system can be determined based on a generalized model of tooth movement (e.g., based on experimental, modeling, clinical data, etc.), making it not necessarily necessary to use patient-specific data. In some embodiments, the determination of the force system involves calculating a specific force value to be applied to one or more teeth to produce a specific movement. Alternatively, the determination of the force system can be performed at a high level without calculating specific force values ​​for the teeth. For example, block 1504 may involve determining a specific type of force to be applied (e.g., compressive force, invasive force, translational force, rotational force, tilting force, torsional force, etc.) without calculating the specific magnitude and / or direction of the force.

[0228] Determining the force system can include constraints on permissible forces, such as permissible direction and magnitude, and the desired movement resulting from the applied forces. For example, different patients may require different mobilization strategies when fabricating a palatal expander. For instance, the amount of force required to separate the palate can depend on the patient's age, as very young patients may not have a fully formed suture. Therefore, in adolescent patients and others with incompletely closed palatal sutures, palatal expansion can be accomplished with a lower force. Slower palatal movement can also help bone growth to fill the expanding suture. For other patients, a faster expansion may be required, which can be achieved by applying greater forces. The structure and materials of the appliance can be selected based on these requirements; for example, by selecting a palatal expander capable of applying large forces to open the palatal suture and / or induce rapid expansion of the palate. Subsequent appliance stages can be designed to apply varying amounts of force, such as initially applying large forces to break the suture, followed by smaller forces to maintain suture separation or gradually expand the palate and / or dental arch.

[0229] Determining the force system may also involve modeling the patient's facial structures, such as the skeletal structure of the jaw and palate. For example, scan data of the palate and dental arch (such as X-ray data or 3D optical scan data) can be used to determine parameters of the skeletal and muscular systems of the patient's oral cavity in order to determine the force sufficient to provide the desired expansion of the palate and / or dental arch. In some embodiments, the thickness and / or density of the palatal suture may be measured or entered by a treatment professional. In other embodiments, the treatment professional may select appropriate treatment based on the patient's physiological characteristics. For example, the characteristics of the palate may also be estimated based on factors such as the patient's age; for instance, a young adolescent patient may require less force to expand the suture than an older patient because the suture has not yet fully formed.

[0230] In box 1506, the design for an orthodontic appliance configured to generate a force system is defined. This design may include appliance geometry, material composition, and / or material properties, and may be determined in various ways, such as using a treatment or force application simulation environment. The simulation environment may include, for example, a computer modeling system, a biomechanical system, or a device. Optionally, a digital model of the appliance and / or teeth, such as a finite element model, may be generated. The finite element model can be created using computer program application software available from various vendors. To create the solid geometry model, computer-aided engineering (CAE) or computer-aided design (CAD) programs, such as AutoCAD® software products available from Autodesk, Inc., San Rafael, California, can be used. To create and analyze the finite element model, program products from multiple vendors can be used, including, but not limited to, the finite element analysis package from ANSYS, Inc., Fort Cannons, Pennsylvania, and the SIMULIA (Abaqus) software product from Dassault Systèmes, Waltham, Massachusetts.

[0231] Optionally, one or more designs can be selected for testing or force modeling. As described above, the desired tooth movement and the required or desired force system to induce the desired tooth movement can be identified. Using a simulation environment, candidate designs can be analyzed or modeled to determine the actual force system generated by using the candidate apparatus. Optionally, one or more modifications can be made to the candidate apparatus, and force modeling can be further analyzed as described, for example, to iteratively determine the apparatus design that produces the desired force system.

[0232] In block 1508, instructions for manufacturing orthodontic appliances incorporating the design are generated. The instructions may be configured to control a manufacturing system or apparatus to produce orthodontic appliances having the specified design. In some embodiments, the instructions are configured to manufacture the orthodontic appliance using direct manufacturing methods (e.g., stereolithography, selective laser sintering, fused deposition modeling, 3D printing, continuous direct manufacturing, multimaterial direct manufacturing, etc.) according to the various methods presented herein. In alternative embodiments, the instructions may be configured to indirectly manufacture the appliance, such as by thermoforming.

[0233] While the steps described above illustrate a method 1500 for designing orthodontic appliances according to some embodiments, those skilled in the art will recognize some variations based on the teachings described herein. Some steps may include sub-steps. Some steps may be repeated frequently as needed. One or more steps of method 1500 can be performed using any suitable manufacturing system or apparatus, such as the embodiments described herein. Some steps may be optional; for example, the process in box 1504 may be omitted, such that the orthodontic appliance is designed based on desired tooth movement and / or determined tooth movement paths rather than on a force system. Furthermore, the order of the steps may be changed as needed.

[0234] Figure 16 A method 1600 for orthodontic treatment and / or design or manufacture of a digital planning appliance is illustrated according to an embodiment. Method 1600 can be applied to any treatment procedure described herein and can be performed by any suitable data processing system.

[0235] In box 1602, a digital representation of the patient's teeth is received. The digital representation may include surface topography and / or color data of the patient's oral cavity (including teeth, gingival tissue, etc.). The surface topography and / or color data may be generated by directly scanning the oral cavity, a physical model (positive or negative mold) of the oral cavity, or an impression of the oral cavity using a suitable scanning device (e.g., a handheld scanner, a desktop scanner, etc.).

[0236] In box 1604, one or more treatment phases are generated based on the digital representation of the teeth. A treatment phase can be an incremental repositioning phase in the orthodontic treatment process, designed to move one or more of the patient's teeth from an initial tooth arrangement to a target arrangement. For example, a treatment phase can be generated by determining the initial tooth arrangement indicated by the digital representation, determining the target tooth arrangement, and determining the movement path for one or more teeth in the initial arrangement required to achieve the target tooth arrangement. The movement path can be optimized based on minimizing the total distance of movement, preventing collisions between teeth, avoiding more difficult tooth movements, or any other suitable criteria.

[0237] In box 1606, at least one orthodontic appliance is manufactured based on the generated treatment phase. For example, a set of appliances may be manufactured, each appliance shaped according to a tooth alignment specified by one of the treatment phases, such that the appliances can be worn sequentially by the patient to incrementally reposition the teeth from the initial alignment to the target alignment. The appliance set may include one or more of the orthodontic appliances described herein. The manufacture of the appliances may involve creating a digital model of the appliance to serve as input to a computer-controlled manufacturing system. Direct manufacturing methods, indirect manufacturing methods, or a combination thereof may be used to form the appliances, as needed.

[0238] In some cases, the phased division of various arrangements or treatment stages may not be necessary for the design and / or manufacture of the device. For example... Figure 16 As shown by the dashed lines, the design and / or manufacture of orthodontic appliances and possible specific orthodontic treatments may include using a representation of the patient's teeth (e.g., including receiving a digital representation of the patient's teeth (box 1602)), and then designing / or manufacturing orthodontic appliances based on the representation of the patient's teeth in the arrangement represented by the received representation.

[0239] As described herein, the techniques described herein can be used to directly manufacture dental appliances, such as orthodontic appliances and / or a series of appliances having tooth-accommodating cavities, which are configured to move a person’s teeth from an initial alignment toward a target alignment according to a treatment plan. Orthodontic appliances may include mandibular repositioning elements, such as those described in the following documents: U.S. Patent No. 10,912,629, filed November 30, 2015, entitled “Dental Appliances with Repositioning Jaw Elements”; U.S. Patent No. 10,537,406, filed September 19, 2014, entitled “Dental Appliances with Repositioning Jaw Elements”; and U.S. Patent No. 9,844,424, filed February 21, 2014, entitled “Dental Appliances with Repositioning Jaw Elements”; the entire disclosure of these U.S. patents is incorporated herein by reference in its entirety.

[0240] The techniques used in this article can also be used to manufacture attachment placement devices, such as appliances for positioning prefabricated attachments on a person's teeth according to one or more aspects of a treatment plan. Examples of attachment placement devices (also known as “attachment placement devices” or “attachment manufacturing templates”) can be found in at least the following: U.S. Application No. 17 / 249,218, filed February 24, 2021, entitled “Flexible 3D Printed Orthodontic Device”; U.S. Application No. 16 / 366,686, filed March 27, 2019, entitled “Dental Attachment Placement Structure”; U.S. Application No. 15 / 674,662, filed August 11, 2017, entitled “Devices and Systems for Creation of Attachments”; U.S. Patent No. 11,103,330, filed June 14, 2017, entitled “Dental Attachment Placement Structure”; and U.S. Application No. 16 / 366,686, filed December 9, 2015, entitled “Dental Attachment Placement”. U.S. Patent Application No. 14 / 963,527 entitled “Dental Attachment Placement Structure”, filed November 12, 2015; U.S. Patent Application No. 14 / 939,246 entitled “Dental Attachment Placement Structure”, filed November 12, 2015; U.S. Patent Application No. 14 / 939,252 entitled “Dental Attachment Formation Structures”, filed November 12, 2015; and U.S. Patent No. 9,700,385 entitled “Attachment Structure”, filed August 22, 2014; the entire contents of which are incorporated herein by reference.

[0241] The techniques described herein can be used to manufacture incremental palatal expanders and / or a series of incremental palatal expanders for expanding a person's palate from an initial position toward a target position according to one or more aspects of a treatment plan. Examples of incremental palatal expanders can be found in at least the following: U.S. Application No. 16 / 380,801, filed April 10, 2019, entitled "Releasable Palatal Expanders"; U.S. Application No. 16 / 022,552, filed June 28, 2018, entitled "Devices, Systems, and Methods for Dental Arch Expansion"; U.S. Patent No. 11,045,283, filed June 8, 2018, entitled "Palatal Expander with Skeletal Anchorage Devices"; U.S. Application No. 15 / 831,159, filed December 4, 2017, entitled "Palatal Expanders and Methods of Expanding a Palate"; and U.S. Application No. 16 / 380,801, filed December 4, 2017, entitled "Methods..." U.S. Patent No. 10,993,783, entitled "Methods and Apparatuses for Customizing a Rapid Palatal Expander"; and U.S. Patent No. 7,192,273, filed August 7, 2003, entitled "System and Method for Palatal Expansion"; the entire contents of which are incorporated herein by reference. Example

[0242] The following non-limiting examples further illustrate this technique. Example 1: Light field prediction model using ray tracing

[0243] This example illustrates the use of a ray-tracing-based method to predict the global optical dose in a simulated material. Predictions were made for different numbers and configurations of lasers sweeping across a single plane. Each laser was modeled as sweeping a semicircle per second (from horizontally to the right). The range of motion was discretized into 100 uniformly spaced segments with independently tunable intensities. The predictions were used in an optimization procedure to determine the laser intensity over time to achieve the target shape. Figures 17A to 21BThe illustration shows the normalized light dose calculated using the sigmoid function, which is adjusted to center its center near the middle of the light dose range set for a specific model.

[0244] Figure 17A It is a thermal image showing the globally optimized optical dose using three collimated lasers and two reflectors, and Figure 17B This is a heatmap image of the target shape used for optimization. Ray tracing is performed using three collimated lasers located at (10, 130), (50, 130), and (90, 130) on top of the simulated material. Vertical reflectors are located at X = -20 and X = 120. Optimization is performed globally across the entire plane.

[0245] Figure 18A It is a thermal image showing the globally optimized optical dose using five collimated lasers and two reflectors, and Figure 18B This is a heatmap image of the target shape used for optimization. Ray tracing was performed using five collimated lasers located on top of the simulated material at (10, 130), (30, 130), (50, 130), (70, 130), and (90, 130). Vertical reflectors were located at X = -20 and X = 120. Optimization was performed globally across the entire plane.

[0246] Figure 19A It is a thermal image showing the globally optimized optical dose using ten collimated lasers and two reflectors, and Figure 19B This is a heatmap image of the target shape used for optimization. Ray tracing was performed using five collimated lasers located at (10, 130), (30, 130), (50, 130), (70, 130), and (90, 130) on top of the simulated material and five collimated lasers located at (10, -30), (30, -30), (50, -30), (70, -30), and (90, -30) on the bottom of the simulated material. Vertical reflectors were located at X = -20 and X = 120. Optimization was performed globally across the entire plane.

[0247] Figure 20A It is a thermal image showing the locally optimized optical dose using ten collimated lasers and two reflectors, and Figure 20BThis is a heatmap image of the target shape used for optimization. Ray tracing was performed using five collimated lasers located at (10, 130), (30, 130), (50, 130), (70, 130), and (90, 130) on top of the simulated material, and five collimated lasers located at (10, -30), (30, -30), (50, -30), (70, -30), and (90, -30) on the bottom of the simulated material. Vertical reflectors were located at X = -20 and X = 120. Optimization was performed locally for the boundary regions of the target shape (ignoring errors in the domain that were not near the edges of the target shape).

[0248] Figure 21A It is a thermal image showing the locally optimized optical dose using ten converging lasers and two reflectors, and Figure 21B This is a heatmap image of the target shape used for optimization. Ray tracing was performed using five converging lasers located at (10, 130), (30, 130), (50, 130), (70, 130), and (90, 130) on top of the simulated material, and five converging lasers located at (10, -30), (30, -30), (50, -30), (70, -30), and (90, -30) on the bottom of the simulated material. Vertical reflectors were located at X = -20 and X = 120. Optimization was performed locally for the boundary regions of the target shape (ignoring errors in the domain that were not near the edges of the target shape).

[0249] In summary, these results demonstrate that the number and location of lasers can significantly affect the accuracy of object geometry. Laser collimation is another parameter that can influence geometry. Optimizing only voxels near the boundaries can achieve better accuracy in the region of interest while relaxing constraints at other locations in the computational domain. Example 2: Comparison of layer-by-layer scanning and volumetric scanning processes

[0250] This example illustrates a comparison of global optical dose achieved via layer-by-layer scanning versus volumetric scanning. Following the method described in Example 1 above, a ray-tracing-based approach is used to predict global optical dose in a simulated material. Figures 22A to 22D The illustration shows the normalized light dose calculated using the sigmoid function, which is adjusted to center its center near the middle of the light dose range set for a specific model.

[0251] Figure 22A It is a heat map image showing the shape of the target object. Figure 22B This is a thermal map showing the predicted global optical dose using five lasers and layer-by-layer scanning. Figure 22C This is a thermal map showing the predicted global optical dose using five lasers and volumetric scanning, and Figure 22DThis is a thermal map showing the predicted global optical dose using a single laser and layer-by-layer scanning. For layer-by-layer scanning ( Figure 22B and Figure 22D The computational domain was divided into 20 horizontal layers with a layer height of 5 mm, and the optical dose for sequential scanning of the layers was calculated. For volumetric scanning, the optical dose for scanning the entire XY plane in one pass was calculated. For a five-laser configuration ( Figure 22B and Figure 22C The lasers are located above the simulated material at (10, 130), (30, 130), (50, 130), (70, 130), and (90, 130). For a single laser configuration ( Figure 22D The laser is located above the simulated material at (50, 130).

[0252] These results indicate that, compared with volumetric scanning ( Figure 22C Compared to layer-by-layer scanning, Figure 22B This can produce improved resolution and fidelity for the shape of the target object. The resolution and fidelity of the layer-by-layer scanning process can also be improved by including multiple lasers (…). Figure 22B Instead of a single laser () Figure 22D To improve. Additional examples

[0253] The following examples are included to further describe some aspects of this technology, and these examples are not intended to limit the scope of this technology.

[0254] Clause 1. A method comprising: (a) Forming a portion of an additively manufactured object within a reservoir of curable material by the following steps: The first energy beam from the first energy source scans through a first scanning region within the reservoir of the curable material. A second energy beam from a second energy source scans through a second scanning region within the reservoir of the curable material, wherein the second scanning region overlaps with the first scanning region at one or more object locations. A combined energy dose, greater than or equal to a threshold dose for solidifying the curable material, is delivered to the one or more object locations using the first energy beam and the second energy beam. (b) Proceeding the reservoir of the curable material forward relative to the first energy source and the second energy source; and (c) Repeat the processes of (a) and (b) to manufacture the additively manufactured object.

[0255] Clause 2. The method according to Clause 1, wherein the first energy beam and the second energy beam simultaneously scan through at least one of the one or more object locations.

[0256] Clause 3. The method according to Clause 1 or 2, wherein the first energy beam and the second energy beam are sequentially scanned through at least one of the one or more object locations.

[0257] Clause 4. The method according to any one of Clauses 1 to 3 further includes: While controlling the activation mode of the first energy source to scan through the first scanning region, and The activation mode of the second energy source is controlled while the second energy beam scans through the second scanning region.

[0258] Clause 5. The method according to Clause 4, wherein the activation modes of the first energy source and the second energy source are configured to selectively solidify the curable material at the one or more object locations.

[0259] Clause 6. The method according to any one of Clauses 1 to 5 further includes: While controlling the energy intensity of the first energy source to scan through the first scanning region, and The energy intensity of the second energy source is controlled while the second energy beam scans through the second scanning region.

[0260] Clause 7. The method according to Clause 6, wherein the energy intensities of the first energy source and the second energy source are configured to selectively solidify the curable material at the one or more object locations.

[0261] Clause 8. The method according to any one of Clauses 1 to 7, wherein the curable material does not solidify at one or more other locations different from the location of the one or more objects.

[0262] Clause 9. The method according to Clause 8, wherein the one or more other locations are located only in the first scan area or only in the second scan area.

[0263] Clause 10. The method according to Clause 8, wherein the second scanning region overlaps with the first scanning region at one or more other locations, and wherein the combined energy dose delivered to the one or more other locations using the first energy beam and the second energy beam is less than a threshold dose for solidifying the curable material.

[0264] Clause 11. The method according to any one of Clauses 1 to 10, wherein: Scanning the first energy beam of the first energy source includes guiding the first energy beam onto a first rotating optical element, and Scanning the second energy beam of the second energy source includes guiding the second energy beam onto the second rotating optical element.

[0265] Clause 12. The method according to any one of Clauses 1 to 11, wherein the first scanning area and the second scanning area are located in the same plane.

[0266] Clause 13. The method according to any one of Clauses 1 to 11, wherein the first scanning area and the second scanning area are located in different planes.

[0267] Clause 14. The method according to any one of Clauses 1 to 13, wherein one or more of the first scanning region or the second scanning region are located in a plane orthogonal to the direction of movement of the reservoir.

[0268] Clause 15. The method according to any one of Clauses 1 to 14, wherein the first energy source and the second energy source are arranged in an array orthogonal to the direction of movement of the reservoir.

[0269] Clause 16. The method according to any one of Clauses 1 to 15, wherein the process of (a) further comprises: The third energy beam from the third energy source scans through a third scanning region within the reservoir of the curable material, wherein the third scanning region overlaps with the first and second scanning regions at one or more object locations. A combined energy dose greater than or equal to a threshold dose for solidifying the curable material is delivered to one or more object locations using the first energy beam, the second energy beam, and the third energy beam.

[0270] Clause 17. The method according to any one of Clauses 1 to 16, wherein the reservoir includes an upper opening, and the first energy beam and the second energy beam are directed through the upper opening of the reservoir to reach the curable material.

[0271] Clause 18. The method according to any one of Clauses 1 to 17, wherein the curable material comprises a resin, the resin comprising one or more polymerizable components.

[0272] Clause 19. The method according to any one of Clauses 1 to 18, wherein the additive manufacturing object includes dental appliances.

[0273] Clause 20. A system for manufacturing additively manufactured objects, the system comprising: The first energy source is configured to output the first energy beam; The second energy source is configured to output a second energy beam; Storage container for curable materials; Processor; and A memory, operatively coupled to the processor and storing instructions that, when executed by the processor, cause the system to perform operations, including: (a) A portion of the additively manufactured object is formed by the following steps: The first energy beam is made to scan through a first scanning region within the reservoir of the curable material. The second energy beam scans through a second scanning region within the reservoir of the curable material, wherein the second scanning region overlaps with the first scanning region at one or more object locations, and A combined energy dose, greater than or equal to a threshold dose for solidifying the curable material, is delivered to the one or more object locations using the first energy beam and the second energy beam. (b) Proceeding the reservoir of the curable material forward relative to the first energy source and the second energy source; and (c) Repeat the processes of (a) and (b) to manufacture the additively manufactured object.

[0274] Clause 21. The system according to Clause 20, wherein the first energy beam and the second energy beam simultaneously scan through at least one of the one or more object locations.

[0275] Clause 22. The system according to Clause 20 or 21, wherein the first energy beam and the second energy beam sequentially scan through at least one of the one or more object locations.

[0276] Clause 23. The system according to any one of Clauses 20 to 22, wherein the operation further comprises: While controlling the activation mode of the first energy source to scan through the first scanning region, and The activation mode of the second energy source is controlled while the second energy beam scans through the second scanning region.

[0277] Clause 24. The system according to Clause 23, wherein the activation modes of the first energy source and the second energy source are configured to selectively solidify the curable material at the one or more object locations.

[0278] Clause 25. The system according to any one of Clauses 20 to 24, wherein the operation further comprises: While controlling the energy intensity of the first energy source to scan through the first scanning region, and The energy intensity of the second energy source is controlled while the second energy beam scans through the second scanning region.

[0279] Clause 26. The system according to Clause 25, wherein the energy intensities of the first energy source and the second energy source are configured to selectively solidify the curable material at one or more object locations.

[0280] Clause 27. The system according to any one of Clauses 20 to 26, wherein the curable material does not solidify at one or more other locations different from the location of the one or more objects.

[0281] Clause 28. The system according to Clause 27, wherein the one or more other locations are located only in the first scan area or only in the second scan area.

[0282] Clause 29. The system according to Clause 27, wherein the second scanning region overlaps with the first scanning region at one or more other locations, and wherein the combined energy dose delivered to the one or more other locations using the first energy beam and the second energy beam is less than a threshold dose for solidifying the curable material.

[0283] Clause 30. The system pursuant to any one of Clauses 20 to 29, wherein: The first energy source includes a first rotating optical element configured to control the direction of the first energy beam, and The second energy source includes a second rotating optical element configured to control the direction of the second energy beam.

[0284] Clause 31. The system according to any one of Clauses 20 to 30, wherein the first scanning area and the second scanning area are located in the same plane.

[0285] Clause 32. The system according to any one of Clauses 20 to 30, wherein the first scanning area and the second scanning area are located in different planes.

[0286] Clause 33. The system according to any one of Clauses 20 to 32, wherein one or more of the first scanning region or the second scanning region are located in a plane orthogonal to the direction of movement of the reservoir.

[0287] Clause 34. The system according to any one of Clauses 20 to 33, wherein the first energy source and the second energy source are arranged in an array orthogonal to the direction of movement of the reservoir.

[0288] Clause 35. The system according to any one of Clauses 20 to 34 further includes a third energy source configured to output a third energy beam.

[0289] Clause 36. The system pursuant to Clause 35, wherein the process of (a) further comprises: The third energy beam scans through a third scanning region within the reservoir of the curable material, wherein the third scanning region overlaps with the first and second scanning regions at one or more object locations. A combined energy dose greater than or equal to a threshold dose for solidifying the curable material is delivered to one or more object locations using the first energy beam, the second energy beam, and the third energy beam.

[0290] Clause 37. The system according to any one of Clauses 20 to 36, wherein the reservoir includes an upper opening, and the first energy beam and the second energy beam are guided through the upper opening of the reservoir to reach the curable material.

[0291] Clause 38. The system according to any one of Clauses 20 to 37, wherein the curable material comprises a resin, the resin comprising one or more polymerizable components.

[0292] Clause 39. The system according to any one of Clauses 20 to 38, wherein the additive manufacturing object includes dental appliances.

[0293] Clause 40. A non-transitory computer-readable storage medium comprising instructions that, when executed by one or more processors of an additive manufacturing system, cause the additive manufacturing system to perform operations, the operations including: (a) Forming a portion of an additively manufactured object within a reservoir of curable material by the following steps: The first energy beam from the first energy source scans through a first scanning region within the reservoir of the curable material. A second energy beam from a second energy source scans through a second scanning region within the reservoir of the curable material, wherein the second scanning region overlaps with the first scanning region at one or more object locations. A combined energy dose, greater than or equal to a threshold dose for solidifying the curable material, is delivered to the one or more object locations using the first energy beam and the second energy beam. (b) Proceeding the reservoir of the curable material forward relative to the first energy source and the second energy source; and (c) Repeat the processes of (a) and (b) to manufacture the additively manufactured object.

[0294] Clause 41. A method comprising: Receive a 3D digital representation of the object to be manufactured; Multiple 2D cross sections are generated from the 3D digital representation; Scanning parameters for a plurality of energy sources are determined to form the plurality of 2D cross sections from a curable material, wherein the plurality of energy sources are configured to scan through a plurality of corresponding scanning regions within the curable material, and wherein the plurality of corresponding scanning regions overlap at one or more object locations; and Instructions are generated for manufacturing the object from the curable material using the plurality of energy sources having the scan parameters.

[0295] Clause 42. The method according to Clause 41, wherein the scanning parameters are configured to deliver a combined energy dose greater than or equal to a threshold dose for consolidating the curable material to the one or more object locations from the plurality of energy sources.

[0296] Clause 43. The method according to Clause 41 or 42, wherein the scanning parameters are configured to cause the plurality of energy sources to selectively solidify the curable material at one or more object locations, while not solidifying the curable material at one or more other locations different from the one or more object locations.

[0297] Clause 44. The method according to any one of Clauses 41 to 43, wherein, for each of the plurality of energy sources, the scanning parameters include one or more of the following: whether the energy source is on or off, the energy intensity of the energy source, or the sweep rate of the energy source.

[0298] Clause 45. The method according to any one of Clauses 41 to 44, wherein each energy source is configured to output a corresponding energy beam that scans through a corresponding scan region.

[0299] Clause 46. The method according to any one of Clauses 41 to 45, wherein determining the scanning parameters comprises: Generate predicted results of the object geometry formed using the plurality of energy sources with the said scanning parameters, and The predicted geometry of the object is compared with at least one of the plurality of 2D cross sections.

[0300] Clause 47. The method according to Clause 46, wherein ray tracing is used to generate the prediction result.

[0301] Clause 48. The method according to Clause 46, wherein an analytical expression is used to generate the prediction result.

[0302] Clause 49. The method according to any one of Clauses 46 to 48, wherein the prediction result is generated based on one or more system parameters of an additive manufacturing system comprising the plurality of energy sources.

[0303] Clause 50. The method according to Clause 49, wherein the one or more system parameters include the locations of the plurality of energy sources.

[0304] Clause 51. The method according to Clause 49 or 50, wherein the one or more system parameters include the position of one or more reflective elements configured to deflect an energy beam generated by at least one of the plurality of energy sources.

[0305] Clause 52. The method according to any one of Clauses 46 to 51, wherein the comparison includes calculating the error between a predicted result of the object geometry and the at least one 2D cross section.

[0306] Clause 53. The method according to any one of Clauses 46 to 52, wherein determining the scanning parameters further comprises: The scanning parameters are modified based on the comparison results, and A second prediction result is generated using the object geometry formed by the plurality of energy sources with modified scanning parameters.

[0307] Clause 54. The method according to any one of Clauses 46 to 53, wherein the object includes dental appliances.

[0308] Clause 55. A system comprising: Processor; and A memory, operatively coupled to the processor and storing instructions that, when executed by the processor, cause the system to perform operations, including: Receive a 3D digital representation of the object to be manufactured. Multiple 2D cross sections are generated from the 3D digital representation. Scanning parameters for a plurality of energy sources are determined to form the plurality of 2D cross sections from a curable material, wherein the plurality of energy sources are configured to scan through a plurality of corresponding scanning regions within the curable material, and wherein the plurality of corresponding scanning regions overlap at one or more object locations; and Instructions are generated for manufacturing the object from the curable material using the plurality of energy sources having the scan parameters.

[0309] Clause 56. The system according to Clause 55, wherein the scanning parameters are configured to deliver a combined energy dose greater than or equal to a threshold dose for consolidating the curable material to the one or more object locations from the plurality of energy sources.

[0310] Clause 57. A system according to Clause 55 or 56, wherein the scanning parameters are configured to cause the plurality of energy sources to selectively solidify the curable material at one or more object locations, while not solidifying the curable material at one or more other locations different from the one or more object locations.

[0311] Clause 58. The system according to any one of Clauses 55 to 57, wherein, for each of the plurality of energy sources, the scanning parameters include one or more of the following: whether the energy source is on or off, the energy intensity of the energy source, or the sweep rate of the energy source.

[0312] Clause 59. The system according to any one of Clauses 55 to 58, wherein each energy source is configured to output a corresponding energy beam that scans through a corresponding scan region.

[0313] Clause 60. The system according to any one of Clauses 55 to 59, wherein determining the scanning parameters includes: Generate predicted results of the object geometry formed using the plurality of energy sources with the said scanning parameters, and The predicted geometry of the object is compared with at least one of the plurality of 2D cross sections.

[0314] Clause 61. The system according to Clause 60, wherein the prediction result is generated using ray tracing.

[0315] Clause 62. The system according to Clause 60, wherein the prediction result is generated using an analytical expression.

[0316] Clause 63. The system according to any one of Clauses 60 to 62, wherein the prediction result is generated based on one or more system parameters of the additive manufacturing system including the plurality of energy sources.

[0317] Clause 64. The system according to Clause 63, wherein the one or more system parameters include the locations of the plurality of energy sources.

[0318] Clause 65. The system according to Clause 63 or 64, wherein the one or more system parameters include the position of one or more reflective elements configured to deflect an energy beam generated by at least one of the plurality of energy sources.

[0319] Clause 66. The system according to any one of Clauses 60 to 65, wherein the comparison includes calculating the error between the predicted geometry of the object and the at least one 2D cross section.

[0320] Clause 67. The system according to any one of Clauses 60 to 66, wherein determining the scanning parameters further comprises: The scanning parameters are modified based on the comparison results, and A second prediction result is generated using the object geometry formed by the plurality of energy sources with modified scanning parameters.

[0321] Clause 68. The system according to any one of Clauses 55 to 67, wherein the object includes dental appliances.

[0322] Clause 69. A non-transitory computer-readable storage medium comprising instructions that, when executed by one or more processors of a computing system, cause the computing system to perform operations, the operations including: Receive a 3D digital representation of the object to be manufactured; Multiple 2D cross sections are generated from the 3D digital representation; Scanning parameters for a plurality of energy sources are determined to form the plurality of 2D cross sections from a curable material, wherein the plurality of energy sources are configured to scan through a plurality of corresponding scanning regions within the curable material, and wherein the plurality of corresponding scanning regions overlap at one or more object locations; and Instructions are generated for manufacturing the object from the curable material using the plurality of energy sources having the scan parameters. in conclusion

[0323] While many embodiments of systems, apparatuses, and methods for manufacturing dental appliances have been described above, this technology is applicable to other applications and / or other methods, such as manufacturing other types of objects (e.g., prototypes, hybrid composites, integrated electronics, medical devices, or aerospace materials or devices). Furthermore, many of the methods, techniques, and processes described herein can be directly applied to other forms of volumetric additive manufacturing. In addition, other embodiments besides those described herein are also within the scope of this technology. Furthermore, several other embodiments of this technology may have different configurations, components, or procedures than those described herein. Therefore, those skilled in the art will accordingly understand that this technology may have other embodiments with additional elements, or that the technology may have embodiments without the above references. Figures 1A to 22D Other embodiments of several features shown and described.

[0324] The various processes described herein can be implemented, partially or completely, using program code comprising instructions executable by one or more processors of a computing system to implement specific logical functions or steps within the process. The program code can be stored on any type of computer-readable medium, such as storage devices including disks or hard disk drives. Computer-readable media including code or portions thereof can include any suitable medium known in the art, such as non-transitory computer-readable storage media. Computer-readable media can include volatile and non-volatile, removable and non-removable media implemented using any method or technology for storing and / or transmitting information, including, but not limited to, random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies; compact disc read-only memory (CD-ROM), digital video disc (DVD) or other optical storage devices; magnetic tape cassettes, magnetic tape, disk storage or other magnetic storage devices; solid-state drives (SSDs) or other solid-state storage devices; or any other medium that can be used to store desired information and can be accessed by system devices.

[0325] The description of embodiments of the present technology is not intended to be exhaustive or to limit the technology to the precise forms disclosed above. Singular or plural terms may also include plural or singular terms, respectively, where the context permits. Although specific embodiments and examples of the present technology have been described above for illustrative purposes, various equivalent modifications are possible within the scope of the present technology, as will be recognized by those skilled in the art. For example, while the steps are presented in a given order, alternative embodiments may perform the steps in a different order. The various embodiments described herein may also be combined to provide further embodiments.

[0326] As used herein, the terms “generally,” “basically,” “about,” and similar terms are used as approximate terms rather than terms of degree and are intended to explain the inherent variations in measured or calculated values ​​that would be recognized by one of ordinary skill in the art.

[0327] Furthermore, unless the word “or” is explicitly limited to referring only to a single item that excludes other items in a list of two or more items, its use in such a list should be interpreted as including (a) any single item in the list, (b) all items in the list, or (c) any combination of items in the list. As used herein, the phrase “and / or” in “A and / or B” refers to A alone, B alone, and both A and B. Additionally, the term “including” is used throughout to indicate that at least one or more of the stated features are included, such that no further number of the same features and / or additional features of the same type are excluded.

[0328] In the event of any conflict between this disclosure and any material incorporated herein by reference, this disclosure shall prevail.

[0329] It should also be understood that specific embodiments have been described herein for illustrative purposes, but various modifications may be made without departing from the present technology. Furthermore, while advantages associated with certain embodiments of the present technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments must exhibit such advantages to fall within the scope of the present technology. Therefore, this disclosure and associated technologies may cover other embodiments not explicitly shown or described herein.

Claims

1. A method comprising: (a) Forming a portion of the additively manufactured object within a reservoir of curable material by the following steps: The first energy beam from the first energy source scans through a first scanning region within the reservoir of the curable material. A second energy beam from a second energy source scans through a second scanning region within the reservoir of the curable material, wherein the second scanning region overlaps with the first scanning region at one or more object locations. A combined energy dose is delivered to the one or more object locations using the first energy beam and the second energy beam, the combined energy dose being greater than or equal to a threshold dose for solidifying the curable material. (b) Proceeding the reservoir of the curable material forward relative to the first energy source and the second energy source; and (c) Repeat the processes of (a) and (b) to manufacture the additively manufactured object.

2. The method according to claim 1, wherein, The first energy beam and the second energy beam simultaneously scan through at least one of the one or more object locations.

3. The method according to claim 1 or 2, wherein, The first energy beam and the second energy beam sequentially scan through at least one of the one or more object locations.

4. The method according to any one of claims 1 to 3, further comprising: While controlling the activation mode of the first energy source to scan through the first scanning region, and The activation mode of the second energy source is controlled while the second energy beam scans through the second scanning region.

5. The method according to claim 4, wherein, The activation modes of the first energy source and the second energy source are configured to selectively solidify the curable material at one or more object locations.

6. The method according to any one of claims 1 to 5, further comprising: While controlling the energy intensity of the first energy source to scan through the first scanning region, and The energy intensity of the second energy source is controlled while the second energy beam scans through the second scanning region.

7. The method according to claim 6, wherein, The energy intensities of the first energy source and the second energy source are configured to selectively solidify the curable material at one or more object locations.

8. The method according to any one of claims 1 to 7, wherein, The curable material does not solidify at one or more other locations different from the locations of the one or more objects.

9. The method according to claim 8, wherein, The one or more other locations are located only in the first scan area or only in the second scan area.

10. The method according to claim 8, wherein, The second scanning region overlaps with the first scanning region at one or more other locations, and wherein the combined energy dose delivered to the one or more other locations using the first energy beam and the second energy beam is less than the threshold dose required to solidify the curable material.

11. The method according to any one of claims 1 to 10, wherein: Scanning the first energy beam from the first energy source includes guiding the first energy beam onto a first rotating optical element, and Scanning the second energy beam from the second energy source involves guiding the second energy beam onto a second rotating optical element.

12. The method according to any one of claims 1 to 11, wherein, The first scanning area and the second scanning area are located in the same plane.

13. The method according to any one of claims 1 to 11, wherein, The first scanning area and the second scanning area are located in different planes.

14. The method according to any one of claims 1 to 13, wherein, One or more of the first scanning region or the second scanning region are located in a plane orthogonal to the direction of movement of the reservoir.

15. The method according to any one of claims 1 to 14, wherein, The first energy source and the second energy source are arranged in an array orthogonal to the direction of movement of the storage device.

16. The method according to any one of claims 1 to 15, wherein, The process in (a) also includes: The third energy beam from the third energy source scans through a third scanning region within the reservoir of the curable material, wherein the third scanning region overlaps with the first and second scanning regions at one or more object locations. A combined energy dose is delivered to the one or more object locations using the first energy beam, the second energy beam, and the third energy beam, the combined energy dose being greater than or equal to the threshold dose used to solidify the curable material.

17. The method according to any one of claims 1 to 16, wherein, The reservoir includes an upper opening, through which the first energy beam and the second energy beam are guided to reach the curable material.

18. The method according to any one of claims 1 to 17, wherein, The curable material includes a resin, and the resin includes one or more polymerizable components.

19. The method according to any one of claims 1 to 18, wherein, The additive manufacturing objects include dental appliances.

20. A system for manufacturing additively manufactured objects, the system comprising: The first energy source is configured to output the first energy beam; The second energy source is configured to output a second energy beam; Storage container for curable materials; processor; as well as A memory, operatively coupled to the processor and storing instructions that, when executed by the processor, cause the system to perform operations, including: (a) A portion of the additively manufactured object is formed by the following steps: The first energy beam is made to scan through a first scanning region within the reservoir of the curable material. The second energy beam scans through a second scanning region within the reservoir of the curable material, wherein the second scanning region overlaps with the first scanning region at one or more object locations, and A combined energy dose is delivered to the one or more object locations using the first energy beam and the second energy beam, the combined energy dose being greater than or equal to a threshold dose for solidifying the curable material. (b) Proceeding the reservoir of the curable material forward relative to the first energy source and the second energy source; and (c) Repeat the processes of (a) and (b) to manufacture the additively manufactured object.

21. The system according to claim 20, wherein, The first energy beam and the second energy beam simultaneously scan through at least one of the one or more object locations.

22. The system according to claim 20 or 21, wherein, The first energy beam and the second energy beam sequentially scan through at least one of the one or more object locations.

23. The system according to any one of claims 20 to 22, wherein, The operation also includes: While controlling the activation mode of the first energy source to scan through the first scanning region, and The activation mode of the second energy source is controlled while the second energy beam scans through the second scanning region.

24. The system according to claim 23, wherein, The activation modes of the first energy source and the second energy source are configured to selectively solidify the curable material at one or more object locations.

25. The system according to any one of claims 20 to 24, wherein, The operation also includes: While controlling the energy intensity of the first energy source to scan through the first scanning region, and The energy intensity of the second energy source is controlled while the second energy beam scans through the second scanning region.

26. The system according to claim 25, wherein, The energy intensities of the first energy source and the second energy source are configured to selectively solidify the curable material at one or more object locations.

27. The system according to any one of claims 20 to 26, wherein, The curable material does not solidify at one or more other locations different from the locations of the one or more objects.

28. The system according to claim 27, wherein, The one or more other locations are located only in the first scan area or only in the second scan area.

29. The system according to claim 27, wherein, The second scanning region overlaps with the first scanning region at one or more other locations, and wherein the combined energy dose delivered to the one or more other locations using the first energy beam and the second energy beam is less than the threshold dose required to solidify the curable material.

30. The system according to any one of claims 20 to 29, wherein: The first energy source includes a first rotating optical element configured to control the direction of the first energy beam, and The second energy source includes a second rotating optical element configured to control the direction of the second energy beam.

31. The system according to any one of claims 20 to 30, wherein, The first scanning area and the second scanning area are located in the same plane.

32. The system according to any one of claims 20 to 30, wherein, The first scanning area and the second scanning area are located in different planes.

33. The system according to any one of claims 20 to 32, wherein, One or more of the first scanning region or the second scanning region are located in a plane orthogonal to the direction of movement of the reservoir.

34. The system according to any one of claims 20 to 33, wherein, The first energy source and the second energy source are arranged in an array orthogonal to the direction of movement of the storage device.

35. The system according to any one of claims 20 to 34, further comprising a third energy source configured to output a third energy beam.

36. The system according to claim 35, wherein, The process in (a) also includes: The third energy beam scans through a third scanning region within the reservoir of the curable material, wherein the third scanning region overlaps with the first and second scanning regions at one or more object locations. A combined energy dose is delivered to the one or more object locations using the first energy beam, the second energy beam, and the third energy beam, the combined energy dose being greater than or equal to the threshold dose used to solidify the curable material.

37. The system according to any one of claims 20 to 36, wherein, The reservoir includes an upper opening, and the first energy beam and the second energy beam are guided through the upper opening of the reservoir to reach the curable material.

38. The system according to any one of claims 20 to 37, wherein, The curable material includes a resin, and the resin includes one or more polymerizable components.

39. The system according to any one of claims 20 to 38, wherein, The additive manufacturing objects include dental appliances.

40. A non-transitory computer-readable storage medium including instructions that, when executed by one or more processors of an additive manufacturing system, cause the additive manufacturing system to perform operations, the operations including: (a) Forming a portion of the additively manufactured object within a reservoir of curable material by the following steps: The first energy beam from the first energy source scans through a first scanning region within the reservoir of the curable material. A second energy beam from a second energy source scans through a second scanning region within the reservoir of the curable material, wherein the second scanning region overlaps with the first scanning region at one or more object locations. A combined energy dose is delivered to the one or more object locations using the first energy beam and the second energy beam, the combined energy dose being greater than or equal to a threshold dose for solidifying the curable material. (b) Proceeding the reservoir of the curable material forward relative to the first energy source and the second energy source; and (c) Repeat the processes of (a) and (b) to manufacture the additively manufactured object.

41. A method comprising: Receive a 3D digital representation of the object to be manufactured; Multiple 2D cross sections are generated from the 3D digital representation; Scanning parameters for a plurality of energy sources are determined to form the plurality of 2D cross sections from a curable material, wherein the plurality of energy sources are configured to scan through a plurality of corresponding scanning regions within the curable material, and wherein the plurality of corresponding scanning regions overlap at one or more object locations; and Instructions are generated for manufacturing the object from the curable material using the plurality of energy sources having the scan parameters.

42. The method according to claim 41, wherein, The scanning parameters are configured to deliver a combined energy dose to the one or more object locations from the plurality of energy sources, the combined energy dose being greater than or equal to a threshold dose for solidifying the curable material.

43. The method according to claim 41 or 42, wherein, The scanning parameters are configured to cause the plurality of energy sources to selectively solidify the curable material at one or more object locations, while not solidifying the curable material at one or more other locations different from the one or more object locations.

44. The method according to any one of claims 41 to 43, wherein, For each of the plurality of energy sources, the scanning parameters include one or more of the following: whether the energy source is on or off, the energy intensity of the energy source, or the sweep rate of the energy source.

45. The method according to any one of claims 41 to 44, wherein, Each energy source is configured to output a corresponding energy beam that scans through the corresponding scan region.

46. ​​The method according to any one of claims 41 to 45, wherein, Determining the scan parameters includes: Generate predicted results of the object geometry formed using the plurality of energy sources with the said scanning parameters, and The predicted geometry of the object is compared with at least one of the plurality of 2D cross sections.

47. The method according to claim 46, wherein, The prediction results are generated using ray tracing.

48. The method according to claim 46, wherein, The prediction results are generated using analytical expressions.

49. The method according to any one of claims 46 to 48, wherein, The prediction results are generated based on one or more system parameters of the additive manufacturing system that includes the multiple energy sources.

50. The method according to claim 49, wherein, The one or more system parameters include the locations of the plurality of energy sources.

51. The method according to claim 49 or 50, wherein, The one or more system parameters include the position of one or more reflective elements configured to deflect an energy beam generated by at least one of the plurality of energy sources.

52. The method according to any one of claims 46 to 51, wherein, The comparison includes calculating the error between the predicted geometry of the object and the at least one 2D cross-section.

53. The method according to any one of claims 46 to 52, wherein, Determining the scanning parameters also includes: The scanning parameters are modified based on the comparison results, and A second prediction result is generated using the object geometry formed by the plurality of energy sources with modified scanning parameters.

54. The method according to any one of claims 46 to 53, wherein, The objects include dental appliances.

55. A system comprising: processor; as well as A memory, operatively coupled to the processor and storing instructions that, when executed by the processor, cause the system to perform operations, including: Receive a 3D digital representation of the object to be manufactured; Multiple 2D cross sections are generated from the 3D digital representation; Scanning parameters for a plurality of energy sources are determined to form the plurality of 2D cross sections from a curable material, wherein the plurality of energy sources are configured to scan through a plurality of corresponding scanning regions within the curable material, and wherein the plurality of corresponding scanning regions overlap at one or more object locations; and Instructions are generated for manufacturing the object from the curable material using the plurality of energy sources having the scan parameters.

56. The system according to claim 55, wherein, The scanning parameters are configured to deliver a combined energy dose to the one or more object locations from the plurality of energy sources, the combined energy dose being greater than or equal to a threshold dose for solidifying the curable material.

57. The system according to claim 55 or 56, wherein, The scanning parameters are configured to cause the plurality of energy sources to selectively solidify the curable material at one or more object locations, while not solidifying the curable material at one or more other locations different from the one or more object locations.

58. The system according to any one of claims 55 to 57, wherein, For each of the plurality of energy sources, the scanning parameters include one or more of the following: whether the energy source is on or off, the energy intensity of the energy source, or the sweep rate of the energy source.

59. The system according to any one of claims 55 to 58, wherein, Each energy source is configured to output a corresponding energy beam that scans through the corresponding scan region.

60. The system according to any one of claims 55 to 59, wherein, Determining the scan parameters includes: Generate predicted results of the object geometry formed using the plurality of energy sources with the said scanning parameters, and The predicted geometry of the object is compared with at least one of the plurality of 2D cross sections.

61. The system according to claim 60, wherein, The prediction results were generated using ray tracing.

62. The system according to claim 60, wherein, The prediction results are generated using analytical expressions.

63. The system according to any one of claims 60 to 62, wherein, The prediction results are generated based on one or more system parameters of the additive manufacturing system that includes the multiple energy sources.

64. The system according to claim 63, wherein, The one or more system parameters include the locations of the plurality of energy sources.

65. The system according to claim 63 or 64, wherein, The one or more system parameters include the position of one or more reflective elements configured to deflect an energy beam generated by at least one of the plurality of energy sources.

66. The system according to any one of claims 60 to 65, wherein, The comparison includes calculating the error between the predicted geometry of the object and the at least one 2D cross-section.

67. The system according to any one of claims 60 to 66, wherein, Determining the scanning parameters also includes: The scanning parameters are modified based on the comparison results, and A second prediction result is generated using the object geometry formed by the plurality of energy sources with modified scanning parameters.

68. The system according to any one of claims 55 to 67, wherein, The objects include dental appliances.

69. A non-transitory computer-readable storage medium comprising instructions that, when executed by one or more processors of a computing system, cause the computing system to perform operations, the operations including: Receive a 3D digital representation of the object to be manufactured; Multiple 2D cross sections are generated from the 3D digital representation; Scanning parameters for a plurality of energy sources are determined to form the plurality of 2D cross sections from a curable material, wherein the plurality of energy sources are configured to scan through a plurality of corresponding scanning regions within the curable material, and wherein the plurality of corresponding scanning regions overlap at one or more object locations; and Instructions are generated for manufacturing the object from the curable material using the plurality of energy sources having the scan parameters.

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