Methods and apparatus relating to substructures for 3D objects are described. In an example, a method for providing a three-dimensional halftone threshold matrix is described. The method may comprise receiving a substructure model representing a three-dimensional material structure and populating each location in the substructure model at which the structure exists with a halftone threshold value.

A method for illuminating a three-dimensional area (1), the three-dimensional area being divided into at least two successive layers (2), which are illuminated temporally sequentially, each layer (2) being divided into at least two illumination fields (3) with at least one first subarea (4), one second subarea (4′), if appropriate a third subarea (4″) and if appropriate further subareas, wherein adjacent illumination fields (3) overlap in individual subareas (4′, 4″) to avoid defectively illuminated regions.

A method for illuminating a three-dimensional area (1), the three-dimensional area being divided into at least two successive layers (2), which are illuminated temporally sequentially, each layer (2) being divided into at least two illumination fields (3) with at least one first subarea (4), one second subarea (4′), if appropriate a third subarea (4″) and if appropriate further subareas, wherein adjacent illumination fields (3) overlap in individual subareas (4′, 4″) to avoid defectively illuminated regions.

A system and method for generating investment casting patterns by 3D printing. CAD software is used to generate a hollow 3D model of a solid 3D model of a desired pattern. The pattern is generated by a 3D printer which prints the exterior of the pattern in pattern wax and the interior in support wax.

A system and method for generating investment casting patterns by 3D printing. CAD software is used to generate a hollow 3D model of a solid 3D model of a desired pattern. The pattern is generated by a 3D printer which prints the exterior of the pattern in pattern wax and the interior in support wax.

An exposure control device (31) serves for equipping and/or retrofitting a generative layer-wise building device (1). The latter comprises an exposure device (20) which emits electromagnetic radiation (22) or particle radiation and is configured to irradiate positions to be solidified in a layer in such a way that after cooling they exist as an object cross-section or part of the same. The exposure control device (31) has a first data output interface (36), at which control commands can be output to the exposure device (20). The control commands which are output specify one of a plurality of exposure types wherein an exposure type is defined by a predetermined combination of a radiation energy density to be emitted by the exposure device (20) and a scanning pattern with which the radiation (22) is being directed to a region of a layer of the building material (15). Furthermore, the exposure control device (31) has a second data output interface (37) at which an exposure type can be output in real time in relation to a timing of the output of a control command specifying this exposure type.

An exposure control device (31) serves for equipping and/or retrofitting a generative layer-wise building device (1). The latter comprises an exposure device (20) which emits electromagnetic radiation (22) or particle radiation and is configured to irradiate positions to be solidified in a layer in such a way that after cooling they exist as an object cross-section or part of the same. The exposure control device (31) has a first data output interface (36), at which control commands can be output to the exposure device (20). The control commands which are output specify one of a plurality of exposure types wherein an exposure type is defined by a predetermined combination of a radiation energy density to be emitted by the exposure device (20) and a scanning pattern with which the radiation (22) is being directed to a region of a layer of the building material (15). Furthermore, the exposure control device (31) has a second data output interface (37) at which an exposure type can be output in real time in relation to a timing of the output of a control command specifying this exposure type.

The present disclosure provides three-dimensional (3D) printing processes, apparatuses, software, and systems for the production of at least one desired 3D object. The 3D printer system (e.g., comprising a processing chamber, build module, or an unpacking station) described herein may retain a desired (e.g., inert) atmosphere around the material bed and/or 3D object at multiple 3D printing stages. The 3D printer described herein comprises one or more build modules that may have a controller separate from the controller of the processing chamber. The 3D printer described herein comprises a platform that may be automatically constructed. The invention(s) described herein may allow the 3D printing process to occur for a long time without operator intervention and/or down time.

A recoating unit (40) serves for equipping or retrofitting a device (1) for additive manufacturing of a three-dimensional object (2) by selectively solidifying a building material (15), preferably a powder, layer by layer. The device (1) comprises a recoater (16) movable across a build area (8) for applying a layer (31b, 32b) of the building material (15) within the build area (8) and a solidification device (20) for selectively solidifying the applied layer (31b, 32b) at positions corresponding to a cross-section of the object (2) to be manufactured. The device (1) is formed and/or controlled to repeat the steps of applying and selectively solidifying until the object (2) is completed. The recoating unit (40) comprises at least two recoating rollers (41, 42) spaced apart from each other in a first direction (B1) and extending into a second direction transversely, preferably perpendicularly, to the first direction. At least one of the recoating rollers (41, 42), preferably both of the recoating rollers (41, 42) are formed adjustable in a third direction perpendicular to the first direction and the second direction in the recoating unit (40).

Methods and apparatus relating to substructures for three-dimensional objects are described. In an example, a method comprises receiving a lattice model having a consistent dimensionality and determining a substructure model representing a three-dimensional material structure, the substructure model being based on the lattice model and specifying a variable material distribution. The substructure model may be populated with halftone threshold data to provide a three-dimensional halftone threshold matrix