Abstract: A reflector includes a first reflector section and a second reflector section. The first reflector section extends along a portion of a first ellipse. The second reflector section extends along a portion of a second ellipse, the second ellipse intersecting the first ellipse. The first reflector section and the second reflector section are joined at an intersecting point of the first ellipse and the second ellipse.

Abstract: A method to calibrate a printer, in which printing of a plurality of uniform area fills using a variety of combinations of at least first and second types of correction is controlled, both the first and second type of correction being varied in the variety of combinations; and in which measurement of optical density uniformity of the plurality of uniform area fills is controlled.

Abstract: A three-dimensional object may be generated. Energy may be applied to a layer of build material to cause a first portion of the layer to coalesce and solidify in a first pattern. A cooling agent may be selectively delivered on a second portion of the layer of the build material to reduce a temperature of the second portion in a second pattern, the first and second patterns being independent of each other.

Abstract: In one example, a system for a fuse lamp calibration includes a carriage comprising a heat source to apply heat over a print bed, a heat sensor to capture thermal data of the print bed, and a computing device coupled to the heat sensor to determine a surface flux of the print bed and calibrate the heat source based on the surface flux of the print bed.

Abstract: Methods of generating a three-dimensional object with an additive manufacturing system are described. The method includes depositing a build material within a working area, thereby providing a build material layer, selectively depositing a fusing agent onto a portion of the build material layer, applying energy from a bulk-fusion energy source to the working area, thereby fusing at least a portion of the build material where the fusing agent is deposited, and applying energy from a focused energy source to one or more localized areas of the working area.

Abstract: In one example, an additive manufacturing system includes a processing system to obtain characteristic data including conditions under which a heat reservoir may be added close to a portion of the object, based on the characteristic data, add sacrificial structure data to the three-dimensional object data for a sacrificial heat reservoir structure close to a portion of the object and not connected to the object, and generate multiple slice images from the three-dimensional object data including the sacrificial structure data.

Abstract: Examples include apparatuses, processes, and methods for generating three-dimensional objects. An example apparatus comprises build material distributor and a controller. Examples distribute a particular build layer in a build area of the apparatus over a previous build layer. Examples determine a build layer temperature corresponding to the particular build layer. Examples analyze build layer coverage for the particular build layer based at least in part on a build layer temperature of the previous build layer and the build layer temperature of the particular build layer. Examples selectively recoat the particular build layer with additional build material based at least in part on the build layer coverage for the particular build layer.

Abstract: There is provided a method and apparatus for controlling heat to a build surface. A thermal profile over the build surface is determined. The determined thermal profile over the build surface is compared with an expected thermal profile over the build surface. Based on the comparison, the determined thermal profile over the build surface or the expected thermal profile over the build surface is selected to control an amount of heat provided by a heating module to the build surface.

Abstract: According to one aspect there is provided apparatus for generating a three-dimensional object. The apparatus comprises a first agent distributor to selectively deliver a coalescing agent onto portions of a layer of build material, a second agent distributor to selectively deliver a coalescence modifier agent onto portions of a layer of build material, and a controller to control the agent distributors to selectively deliver each of the agents onto a layer of build material in respective patterns derived from data representing a slice of a three-dimensional object to be generated, so that when energy is applied to the layer the build material coalesces and solidifies to form a slice of the three-dimensional object in accordance the patterns.

Abstract: According to one example, there in provided a system for processing three-dimensional object data representing a three-dimensional object to be generated by an additive manufacturing system. The system comprises a processor to perform a transformation on the three-dimensional object data, and to generate a plurality of slice images from the transformed three dimensional object data.

Abstract: A three dimensional object may be formed by forming voxels on a sheet of material and positioning the voxels together to form the three dimensional object by rolling up the sheet.

Abstract: Temperatures of a layer of build material on a support member may be detected. Each of the temperatures corresponding to a respective area of the layer. Based on data representing the three-dimensional object, a subset of the temperatures may be filtered from spatial temperature distribution data comprising the temperatures. A degree of heat or energy applied to the layer may be controlled based on the filtered spatial temperature distribution data.

Abstract: According to one example, there is provided a method, in a three-dimensional printing system (100), of determining the thickness of a layer of build material formed on a build platform (104). The method comprises forming a layer of build material (402) on a base having predetermined color characteristics, measuring color characteristics of the deposited layer of build material, and determining, based on the measured color characteristics, the thickness of at least a portion of the formed layer of build material.

Abstract: A sensor may be to detect a height profile of build material for generating the three-dimensional object. A defect of the build material may be determined to exist based on the height profile of the build material. The defect may be corrected or the defect may be prevented from impacting a component of the system. A portion of a layer of the build material delivered by a build material distributor may be selectively solidified.

Abstract: An integrated build and material supply system (12) for an additive manufacturing apparatus comprises a building compartment (24) adapted to accommodate an object (50) to be formed by means of additive manufacturing and a storage compartment (22) adapted to store a build material for forming said object. A volume of said building compartment and a volume of said storage compartment are variable in size, and said system is adapted to re-allocate at least a portion of a volume previously allocated to said storage compartment to said building compartment.

Abstract: An example method for cooling a build volume is described. In one implementation, a heating mechanism is set to a temperature identified based on the build material information, and the build volume is heated using the heating mechanism for a time period identified based on the build material information.

Abstract: Apparatus to produce a three-dimensional object and methods of producing a three-dimensional object are described. In some examples, a first fluid comprising a colorant and a second fluid comprising an absorber to absorb electromagnetic radiation are applied on a layer of particulate material. Application of the second fluid to the layer of particulate material is in dependence on an ability of the first fluid to absorb the electromagnetic radiation.

Abstract: In one implementation, a system comprising a target engine, a thermal engine, and a sacrificial object engine is described. The target engine is to identify a target region of a build bed of a print device where a target object is to be located. The thermal engine is to identify a temperature level of the target region. The sacrificial object engine is to identify an object location to place a sacrificial object in response to a determination that the temperature level of the target region is deficient to achieve a temperature threshold for production.

Abstract: An airborne particle detector comprises a light source to emit a light beam through a target space adjacent to a heat source of a 3D printer, a detector to detect an amount of light of the light beam having passed through the target space, and a detection engine in communication with the light source and the detector to detect airborne particles in the target space using an amount of light detected by the detector.

Abstract: Certain described examples relate to the generation of data for use in producing a three-dimensional object. Certain examples utilize lattice indexes to define a lattice associated with a particular portion of the three dimensional object. The lattice index may be used in a matrix generation operation that compares index values with threshold values to generate a three-dimensional lattice matrix. The three-dimensional lattice matrix is useable to instruct a structure of the three-dimensional object.