Abstract: An improved layer normalizing device for use in dimensionally normalizing layers of a three-dimensional model produced by a selective deposition modeling technique. The layer normalizing device employs a wicking member having a body and a normalizing surface for dimensionally normalizing the object while the object is being built layer by layer. The body includes a plurality of interstices, and when the wicking member is sufficiently heated to cause the build material to become flowable, excess material is drawn by capillary action from the layer of the object being normalized and into the wicking member. A refreshing means is provided to remove the excess build material from the interstices of the wicking member and allow the wicking member to draw additional build material by capillary action.

Abstract: An improved stereolithographic process for forming three-dimensional objects using an improved support structure. The support structure is formed by using differential curing of the liquid media material to form solid supports with weak points at selected locations to facilitate support removal from a three-dimensional object and minimize post-processing.

Abstract: A unique scanning technique for selective deposition modeling wherein the dispensing device remains substantially stationary as the object staging structure supporting the three-dimensional objects being formed is reciprocally driven in a main scanning direction. A more uniform temperature environment is provided for the dispensing device which can achieve a more uniform drop mass when dispensing a curable material. Also provided is a unique biased air flow for cooling the layers of the object as they are formed as they release a substantial amount of exothermal heat. The biased air flow is directed away from the dispensing device so a to provide a more uniform temperature environment for the dispensing device while removing the substantial amount of heat from the layers.

Abstract: A method for removing supports from a three-dimensional object formed by solid freeform fabrication. The three-dimensional object and support structure both contain a phase change component in order to achieve the desired phase change characteristics needed for dispensing the material. The method prevents the phase change material within the three-dimensional object from migrating within the object during post processing to remove the support structure.

Abstract: A method of manipulating data in a method for forming a three-dimensional object layer by layer from an ink jettable, solidifiable material by providing data corresponding to a plurality of polygons defining the outer surfaces of a plurality of three-demiensional objects and providing sets of x, y, and z coordinates corresponding to each layer and identifying x and y coordinates with each z coordinate such that directional values and counter values are determined for each y coordinate in a first set of coordinates generated. A second set of y coordinates are generated according to a formula that permits the determined layers to be processed to form a three-dimensional object.

Abstract: Solid state lasers that use non-linear optical crystals to generate frequency tripled or quadrupled output in the ultraviolet have low lifetimes due to damage to the face of the non-linear crystal through which the ultraviolet signal exits. To prevent this damage, the tripling or quadrupling crystal is provided within a controlled environment that is maintained substantially free from contaminants such as silicon-bearing and organic compounds. The tripling or quadrupling crystal is enclosed within a tubular chamber with windows on the ends of the tube that provide optical access to the entrance and exit faces of the tripling or quadrupling crystal. All heating elements and alignment elements for the crystal are outside of the chamber. Because the crystal is stored within the hermetically sealed chamber, contaminants are not available within the environment of the crystal that could interact with the energetic photons of the ultraviolet output of the frequency multiplied solid state laser.

Abstract: A solubilizing agent and a compound made by reacting selected nucleophiles, including fatty acid reactants and amines with an isocyanate are disclosed. The addition of the isocyanate and the different nucleophiles will create a di-urethane tetra-amide solubilizing agent product. The polyamide-solubilizing agent is useful as an ingredient in a phase change solid imaging material and as carrier compositions used to make phase change ink jet inks.

Abstract: A computer-controlled apparatus and method for fabricating three-dimensional articles in layerwise fashion is disclosed. Upon dispensing a layer of a fusible powder, a laser irradiates selected locations of that layer to fuse the powder into a cross-section of the article to be formed in that layer, such that the fused cross-sections fuse together into the article. The laser is controlled in a raster scan fashion across the selected locations of the powder layer. The parallel raster scan lines are separated from one another, centerline-to-centerline, according to a selected pitch, or fill scan spacing value. The positions of the parallel scan lines are determined with respect to a coordinate system at the powder layer, rather than with respect to boundaries of the cross-section being formed; in alternating layers, the parallel scan lines are offset from one another by one-half the pitch.

Abstract: A variety of support structures and build styles for use in Rapid Prototyping and Manufacturing systems are described wherein particular emphasis is given to Thermal Stereolithography, Fused Deposition Modeling, and Selective Deposition Modeling systems, and wherein a 3D modeling system is presented which uses multijet dispensing and a single material for both object and support formation.

Abstract: A method of applying highly viscous paste-like build materials in layers in a solid freeform fabrication apparatus to form three-dimensional objects. A viscosity modifier is first introduced into the build material to establish a low viscosity state and then the material is dispensed in layers on a working surface. The viscosity modifier is then removed from the build material preferably by evaporation, and the layer is selectively solidified to form the three-dimensional object. The method substantially eliminates the undesirable effects of induced shear stress imposed on lower layers when attempting to apply uniform layers of highly viscous materials in solid freeform fabrication techniques. The method allows for the use of highly viscous paste-like materials that can include upwards of 50% by weight of metallic, ceramic, mineral, or polymer powders. Preferably the binder is a photocurable resin or thermocurable material which is selectively solidified to form the three-dimensional objects.

Abstract: A closed loop selective deposition modeling apparatus having a surface scanning system for actively monitoring the surface height of a layer of a three-dimensional object as it is being built by selectively dispensing a build material. The surface scanning system directs a beam of energy on the surface of the object that establishes an illumination zone which emits scattered light, and has a detector which senses the scattered light and produces a response indicative of the surface condition of the object. The response is processed to establish a plurality of height data signals that are further processed to produce feedback data. The feedback data is then utilized to selectively dispense the build material to desired locations on the surface of the object to therein dimensionally normalize the layer of the object being formed.

Abstract: Techniques for controlling jobs in a selective deposition modeling (Selective Deposition Modeling) system. A client computer system can connect directly to a Selective Deposition Modeling system to work with a job queue located at the Selective Deposition Modeling system. Jobs in the job queue may be previewed in three-dimensional form. Moreover, the jobs in the job queue may be manipulated to move the jobs to different positions in the job queue or to delete a job. Additionally, multiple jobs may be automatically combined to generate a single build process.

Abstract: A paste composition, including a binding agent charged with metallic powder, to be used in a solid freeform fabrication procedure, comprising:

Abstract: An illumination system includes optics capable of adjusting the size of a beam of light and adjusting the focus of the beam of light. Spot size control optics adjusts the overall size of the beam of light and separately adjusts the ellipticity of the beam, primarily in one dimension. Light from the spot size control optics passes to focus control optics that control the overall focus of the beam of light and adjust the astigmatism of the beam by altering the focus position of the beam of light in one dimension. The laser system, the spot size control optics and the focus control optics are within an enclosure. Actuators under remote control from outside of the enclosure adjust both of the spot size control optics and focus control optics in the thermal environment of the illumination system.

Abstract: A rapid prototyping and manufacturing (e.g. stereolithography) method and apparatus for making three-dimensional objects on a layer by layer basis by selectively exposing layers of material to prescribed stimulation, using a beam having a first smaller diameter and a beam having a second larger diameter, to form laminae of the object. The power of the smaller beam is typically lower than the power of the larger beam. Object formation is controlled by data representing portions of the layers to be exposed with the larger beam (large spot portions) and those portions to be exposed with the smaller beam (small spot portions). In a preferred embodiment, portions exposed with the larger beam are formed first, for a given layer. Portions are exposed with the small beam next. Thereafter the entire perimeter of the laminae is traced using the small beam.

Abstract: Phase change compositions that are solid at ambient temperature and liquid at an elevated temperature above ambient temperature are disclosed for advantageous use in selective deposition modeling methods for building three-dimensional objects. A phase change composition according to the disclosed invention is a semi-crystalline component mixture having a freezing point of at least about 68° C., a melting point of at least about 88° C. and a viscosity of about 13 centipoise at 135° C. The composition includes a plurality of waxes having a broad melting point range and molecular weight range. Three-dimensional objects having minimal curl, delamination and stress cracks can be produced at a faster rate than heretofore known by using selective deposition modeling techniques employing the disclosed compositions.

Abstract: A rapid prototyping and manufacturing (e.g. stereolithography) method and apparatus for making three-dimensional objects on a layer-by-layer basis by selectively exposing layers of material to prescribed synergistic stimulation including forming portions of a lamina using a first exposure, allowing a time delay, and then applying a second exposure. The time delay is sufficient to allow shrinkage of the material to occur that results from the first exposure. It is preferred that the solidified portion resulting from the first exposure does not adhere to the previously formed lamina. It is also preferred that the portion solidified by this first exposure does not adhere to any boundary region that may have been exposed and adhered to the previously formed lamina. The time delay associated with a given cross-sectional region may be occupied by exposing other cross-sectional regions. The delay may occur between two exposures of overlaying hatch or fill vectors.

Abstract: A component to control the viscosity of phase change material formulations is made by reacting selected nucleophiles, including fatty acid/alcohol reactants with an isocyanate, is disclosed. The addition of the isocyanate and the different nucleophiles will create a viscosity modifying component of low viscosity that can be formulated with higher molecular weight polyamide resins to achieve increased toughness in phase change solid imaging materials and carrier compositions used to make phase change ink jet inks.

Abstract: A method and apparatus for making high resolution objects by stereolithography utilizing low resolution materials which are limited by their inability to form unsupported structures of desired thinness and/or their inability to form coatings of desired thinness. Data manipulation techniques, based on layer comparisons, are used to control exposure in order to delay solidification of the material on at least portions of at least some cross-sections until higher layers of material are deposited so as to allow down-facing features of the object to be located at a depth in the building material which is equal to or exceeds a minimum cure depth that can effectively be used for solidifying these features. Similar data manipulations are used to ensure minimum reliable coating thicknesses exist, above previously solidified material, before attempting solidification of a next layer. In addition, horizontal comparison techniques are used to provide enhanced cross-sectional data for use in forming the object.

Abstract: This invention relates to the formation of three-dimensional objects on substantially layer-by-layer basis with enhanced resolution. The invention utilizes a unique offset printhead containing groups of jets to selectively deposit a hot-melt material.