A 3D printing system may include a tank in which a bottom of the tank is formed by a radiation-transparent flexible membrane, a spill tray with an outer wall configured to contain liquid resin that inadvertently leaks out from the bottom of the tank, and a light source configured to project radiation towards the bottom of the tank. The spill tray may contain an inner opening that allows the radiation from the light source to pass through the spill tray to the tank. A 3D printing system may also include a mask assembly which comprises a mask with pixels configurable to be individually transparent or opaque to portions of the radiation projected from the light source and a mask assembly receiving member configured to receive the mask assembly. The mask assembly may also include a rigid guide portion that is insertable into a slot of the mask assembly receiving member.

A four-dimensional (“4D”)-printing or 4D-additive manufacturing method for producing anisotropic macroscopic structures and/or anisotropic macroscopic materials having a plurality of voxels, comprising: providing or forming a first layer of a photocurable first liquid crystalline (LC) monomer; wherein the first layer of the first LC monomer has been provided or formed at a temperature falling within a nematic phase range of the first LC monomer; applying a magnetic field, having a first three-dimensional (“3D”) magnetic field vector with respect to an origin point of a 3D coordinate system, to the first layer of first LC monomer or one or more of the plurality of voxels within the first layer of first LC monomer for a first dwell time, to produce in alignment with the first 3D magnetic field vector a first molecular director and/or first nematic alignment vector within the first layer of first LC monomer or within each of the one or more of the plurality of voxels within the first layer of first LC monomer; exposing the first layer of first LC monomer or the one or more of the plurality of voxels within the first layer of first LC monomer to a first dose of light radiation.

A four-dimensional (“4D”)-printing or 4D-additive manufacturing method for producing anisotropic macroscopic structures and/or anisotropic macroscopic materials having a plurality of voxels, comprising: providing or forming a first layer of a photocurable first liquid crystalline (LC) monomer; wherein the first layer of the first LC monomer has been provided or formed at a temperature falling within a nematic phase range of the first LC monomer; applying a magnetic field, having a first three-dimensional (“3D”) magnetic field vector with respect to an origin point of a 3D coordinate system, to the first layer of first LC monomer or one or more of the plurality of voxels within the first layer of first LC monomer for a first dwell time, to produce in alignment with the first 3D magnetic field vector a first molecular director and/or first nematic alignment vector within the first layer of first LC monomer or within each of the one or more of the plurality of voxels within the first layer of first LC monomer; exposing the first layer of first LC monomer or the one or more of the plurality of voxels within the first layer of first LC monomer to a first dose of light radiation.

Embodiments of the present disclosure include methods of simultaneously manufacturing two or more hydrogel constructs (e.g., tubular hydrogel constructs). In some embodiments, the method comprises one or more of the following steps: providing a vat comprising a bio-ink composition containing one or more monomers and/or one or more polymers; applying electromagnetic radiation from an electromagnetic radiation source to cure a layer of the hydrogel constructs (e.g., tubular hydrogel constructs); and applying electromagnetic radiation from the electromagnetic radiation source one or more additional times to produce one or more additional layers of the hydrogel constructs (e.g., tubular hydrogel constructs).

Embodiments of the present disclosure include methods of simultaneously manufacturing two or more hydrogel constructs (e.g., tubular hydrogel constructs). In some embodiments, the method comprises one or more of the following steps: providing a vat comprising a bio-ink composition containing one or more monomers and/or one or more polymers; applying electromagnetic radiation from an electromagnetic radiation source to cure a layer of the hydrogel constructs (e.g., tubular hydrogel constructs); and applying electromagnetic radiation from the electromagnetic radiation source one or more additional times to produce one or more additional layers of the hydrogel constructs (e.g., tubular hydrogel constructs).

A method of forming an ophthalmic contact lens using an additive manufacturing apparatus is presented herein. The method providing a first solution comprising HEMA, PEGDA, and a photoinitiator, forming a support structure on a planar print bed of the additive manufacturing apparatus by depositing a first plurality of layers of the first solution and curing the first plurality of layers, and forming an ophthalmic contact lens on the support structure by depositing a second plurality of layers of the first solution and curing the second plurality of layers. The second plurality of layers are arranged such that a disc of the ophthalmic contact lens is oriented generally perpendicular to the planar print bed of the additive manufacturing apparatus.

The present disclosure provides techniques for calibration systems and methods for additive manufacturing systems with multiple image projection. In some embodiments, a method of calibrating two or more image projectors of a photoreactive 3D printing system (PRPS) includes: projecting a sub-image from each of the two or more image projectors; measuring light from an image projector using a light sensor of a calibration system; receiving a signal from the light sensor; processing information from the light sensor; and changing a parameter of a sub-image based on the processed information. In some cases, a PRPS includes a calibration fixture comprising the light sensor. In some cases, a PRPS can be calibrated using a modular calibration fixture comprising the light sensor, wherein the modular calibration fixture can be coupled to the PRPS, leveled and height adjusted, and then a calibration routine can be performed.

The present disclosure provides techniques for calibration systems and methods for additive manufacturing systems with multiple image projection. In some embodiments, a method of calibrating two or more image projectors of a photoreactive 3D printing system (PRPS) includes: projecting a sub-image from each of the two or more image projectors; measuring light from an image projector using a light sensor of a calibration system; receiving a signal from the light sensor; processing information from the light sensor; and changing a parameter of a sub-image based on the processed information. In some cases, a PRPS includes a calibration fixture comprising the light sensor. In some cases, a PRPS can be calibrated using a modular calibration fixture comprising the light sensor, wherein the modular calibration fixture can be coupled to the PRPS, leveled and height adjusted, and then a calibration routine can be performed.

Methods and apparatus comprising a dewetting phase and a polymerization liquid that are immiscible, and can be used for the formation of three-dimensional objects, wherein the method does not require a dead zone. Additionally, methods and apparatus that employ an optically transparent cooling apparatus to mitigate heat generated during the fabrication process, and the use of a mobile phase to provide a shearing interface to reduce interfacial adhesive forces.

Methods and apparatus comprising a dewetting phase and a polymerization liquid that are immiscible, and can be used for the formation of three-dimensional objects, wherein the method does not require a dead zone. Additionally, methods and apparatus that employ an optically transparent cooling apparatus to mitigate heat generated during the fabrication process, and the use of a mobile phase to provide a shearing interface to reduce interfacial adhesive forces.