1984
On 16 July 1984, Alain Le Mťhautť, Olivier de Witte, and Jean Claude
Andrť filed their patent for the stereolithography process. The
application of the French inventors was abandoned by the French General
Electric Company (now Alcatel-Alsthom) and CILAS (The Laser Consortium).
The claimed reason was “for lack of business perspective”.
Three weeks later in 1984, Chuck Hull of 3D Systems Corporation filed
his own patent for a stereolithography fabrication system, in which
layers are added by curing photopolymers with ultraviolet light lasers.
Hull defined the process as a “system for generating three-dimensional
objects by creating a cross-sectional pattern of the object to be
formed,”. Hull’s contribution was the STL (Stereolithography) file
format and the digital slicing and infill strategies common to many
processes today.