초록 ▼

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 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. The delay may alternatively occur between exposure of hatch vectors and boundary vectors. The time delay may be determined by a clock, or alternatively, the time delay may be considered to have lapsed upon certain physical conditions being met, such as detecting the amount of shrinkage and determining that it has progressed far enough for the second exposure to occur.

대표청구항 ▼

1. A method for forming at least a portion of a three-dimensional object, comprising:a) forming a layer of fluid-like resin material over a previously formed lamina of the object; b) exposing the layer to stimulation to form a subsequent lamina of the object adhered to the previously formed lamina;

1. A method for forming at least a portion of a three-dimensional object, comprising:a) forming a layer of fluid-like resin material over a previously formed lamina of the object; b) exposing the layer to stimulation to form a subsequent lamina of the object adhered to the previously formed lamina; c) repeating (a) and (b) to form the object from a plurality of adhered laminae; and d) defining a time period, wherein (b) comprises exposing at least one element in a subsequent lamina being formed in the layer with at least two exposures, wherein a first exposure is followed by a second exposure after a delay substantially equal to or greater than the defined time period, and wherein the first exposure is performed by a beam scanning in a first direction over the element and the second exposure is performed by the beam scanning in a second direction over the element, wherein the first and second directions are different, the delay is determined by a measured or calculated temperature of the resin material that defines an exposure delay time period.