Abstract: A solid freeform fabrication method and apparatus for making objects in a layer by layer manner in which the objects have special geometrical features requiring specialized control parameters. The method and apparatus automatically determines and selects the build parameters for the build process based on automatic part feature recognition. A general build style is first determined having a plurality of default parameters for building the object. Data representing the object is imported and oriented with a Z-axis. The data is then processed by slicing software that automatically identifies special build types for specific ranges of Z-values and selects the alternative parameters needed to successfully build these features. Preferably a look-up table contains special sets of values for the parameters for each special build type possible in which the slicing algorithm can select from. During slicing, operator intervention is not needed to prepare all the parameters necessary for a successful build.

Abstract: A solid freeform fabrication method and apparatus for making objects in a layer by layer manner in which the objects have special geometrical features requiring specialized control parameters. The method and apparatus automatically determines and selects the build parameters for the build process based on automatic part feature recognition. A general build style is first determined having a plurality of default parameters for building the object. Data representing the object is imported and oriented with a Z-axis. The data is then processed by slicing software that automatically identifies special build types for specific ranges of Z-values and selects the alternative parameters needed to successfully build these features. Preferably a look-up table contains special sets of values for the parameters for each special build type possible in which the slicing algorithm can select from. During slicing, operator intervention is not needed to prepare all the parameters necessary for a successful build.

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: 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 rapid prototyping and manufacturing (e.g. stereolithography) method and apparatus for producing three-dimensional objects by selectively subjecting a liquid or other fluid-like material to a beam of prescribed stimulation. In a preferred embodiment a source of prescribed stimulation is controlled to reduce or inhibit the production of the prescribed stimulation during at least some periods when the prescribed stimulation is not needed to expose the material. In another preferred embodiment, the source of stimulation is controlled to vary the quantity of prescribed stimulation that is produced and allowed to reach the material. In an additional preferred embodiment control of laser output occurs based on a combination of supplying a regulated amount of voltage to an AOM in conjunction with temporary sensing of laser power and a known desired power to attain.