Method of making a three-dimensional object by stereolithography

摘要

An improved method for stereolithographically forming a three-dimensional object wherein ordinarily solidified internal walls of the object remain at least partially unsolidified. Any unsolidified medium within the object can be drained from the internal walls of the object prior to post-curing so that a hollow three-dimensional object is formed. The object is formed on a layer by layer basis with the internal portion of each layer of the object formed as a grid of solidified portions and unsolidified portions wherein the solidified and unsolidified portions are different on each layer. Objects formed in this manner can be used as patterns in investment casting.