Although 3D printing only recently became a mainstream topic, its roots trace back to the 80's when Hideo Kodama of Nagoya Municipal Industrial Research Institute published the first account of a working photopolymer rapid prototyping system (1981). Shortly after this, the first form of 3D printing, Stereolithography, was invented by Charles Hull in 1984 (pictured above, image courtesy of industryweek.com). In stereolithography, a digital model can be created from pictures (see the process in the diagram below). This was a huge step forward for engineering and would make waves for inventors. With this invention, users could now test out designs and prototypes more efficiently before investing in large manufacturing batches. Charles Hull went on to found 3D Systems in 1986 which is currently one of the largest 3D printing companies alive today.
*diagram courtesy of solidsmack.com
In 1992 the first Stereolithographic Apparatus (or SLA machine) was produced by 3D Systems
(learn more about SLA printing HERE). The first SLA machine utilized a UV laser solidifying photopolymer, a liquid with the viscosity and color of honey that made objects layer by layer. This was the first form of rapid prototyping that would forever change the world of engineering and design. A modern-day SLA device is pictured on the right.
At around the same time, another form of additive manufacturing was in the works, called Selective Laser Sintering or SLS. In SLS, material in powder form is heated by a strong laser at just below its melting point, causing the powders to sinter together to form the solid 3D object which was intended to be made. This technology patent was filed in 1989 and was later licensed to a company called DTM Inc, which was later acquired by 3D Systems. The SLS process is depicted in the diagram below.
*diagram courtesy of mindtribe.com
1989 was also the year that FDM printing (Fused Deposition Modeling; read more HERE) was patented by the co-founder of Stratasys, 3D System's competitor company. FDM is a proprietary technology still held by Stratasys today, but is also the process used by the majority of consumer machines (based on the open source RepRap model, pictured below).