Why “first” is a hard word here
There is no single machine that everyone agrees was the first 3D printer. What is well documented is that, in the early 1980s, several people in different countries had the same idea: build an object by hardening or joining thin layers of material, one on top of another, under computer control. Which of them counts as first depends on what you count. A published paper, a filed patent, a working prototype and a commercial product all have different dates and different names attached.
The best-known name is Chuck Hull, an American who filed a patent in 1984 and co-founded a company that sold the first commercial machines. But he was not alone, and the history reads better when the other strands are included.
Older ideas that pointed the way
The notion of building shapes from slices is older than computers. In the nineteenth century, the French sculptor François Willème developed “photosculpture,” in which photographs taken from many angles around a sitting subject were used to guide the carving of a likeness. In the 1890s, a patent credited to Joseph Blanther described stacking layers of material to make contour relief maps. Neither is a 3D printer, but both show the layer-and-section idea long before anyone could drive it with a computer.
By the 1970s, the missing ingredients were arriving. Computer-aided design programs could describe solid shapes, small computers could control motors and light sources, and chemists had developed liquid resins that harden when exposed to ultraviolet light. Rising computing power from silicon chips made it practical to slice a digital model into layers automatically.
Japan, 1981
Hideo Kodama, a researcher at the Nagoya Municipal Industrial Research Institute in Japan, published a paper in 1981 describing a method of making a plastic model by exposing a photo-hardening resin layer by layer. His work is usually cited as one of the earliest published descriptions of what became rapid prototyping. According to commonly repeated accounts, he filed an initial patent application but did not complete the full filing within the required time, so the patent did not proceed. Details of that episode vary between sources, so it is safest to say only that his published work came first.
France, 1984
In July 1984, a team in France (usually named as Alain Le Méhauté, Olivier de Witte and Jean-Claude André) filed a patent for a stereolithography process. Reports say the sponsoring companies later dropped the application because they saw no clear business case. A few weeks later, Chuck Hull filed his own application in the United States.
Chuck Hull and stereolithography
Hull’s patent, filed in 1984 and granted in 1986, described building an object by using ultraviolet light to harden successive thin layers of liquid photopolymer. He called the process stereolithography, a term that stuck. In 1986 he helped found 3D Systems, and the company’s first commercial machine, the SLA-1, was introduced in the late 1980s. Hull is also widely credited with the STL file format, which describes a surface as a mesh of triangles and is still common today.
What makes Hull’s role distinctive is less the idea than the follow-through: a patent, a company and a machine that customers could buy.
Other processes from the same decade
Stereolithography was only one route. Within a few years, other approaches appeared:
| Process | Main credited figures | How it works |
|---|---|---|
| Stereolithography | Chuck Hull (and Kodama, French team) | Light hardens liquid resin |
| Selective laser sintering | Carl Deckard, Joe Beaman, University of Texas at Austin | A laser fuses powder, layer by layer |
| Fused deposition modeling | Scott Crump | A heated nozzle extrudes plastic filament |
| Laminated object manufacturing | Michael Feygin and colleagues | Sheets of material are cut and bonded |
| Binder-based powder printing | Researchers at MIT | A print head deposits binder onto powder |
Selective laser sintering was developed in the mid-1980s, and fused deposition modeling was patented around 1989, when Crump also co-founded Stratasys. The MIT work on binder printing, with Emanuel Sachs among those involved, is the origin of the phrase “3D printing” itself. Exact filing dates differ by country, so treat any single year for these as approximate.
What the early machines were used for
The first machines were expensive, slow and aimed at industry. They produced models for design review and fit checks, which is why the field was first called rapid prototyping. Engineers could hold a part in days or hours rather than waiting for tooling to be cut. Building finished production parts came later, as materials and machines improved, and that shift is part of the story of additive manufacturing as a factory technology.
Lasers mattered for several of these processes. The same laser beams that were becoming common in industry and research provided the precise, controllable energy needed to harden resin or fuse powder.
From industrial tool to household word
For about two decades, 3D printing was mainly a professional tool. Things changed when early patents began to expire and open-source projects such as RepRap, started by Adrian Bowyer in 2005, showed that a hobbyist printer could be built cheaply. From around 2009, small consumer-oriented machines appeared, and the broader 3D printing industry grew in both professional and hobby directions.
Why the early patents shaped the field
Patents mattered as much as engineering. A granted patent gave its holder the right to exclude competitors for years, and in this field several holders built companies on them: 3D Systems around stereolithography, DTM around laser sintering, and Stratasys around filament extrusion. For roughly two decades, competition took place mostly between these process families rather than within them, which kept machine prices high and the market focused on industrial buyers.
It also explains why the dates in popular summaries differ. A researcher’s paper, a patent filing, a patent grant and a product launch can each be separated by years, and different writers choose different ones. When reading any claim that a person “invented 3D printing in” a given year, it helps to ask which of those events is meant.
The software side
Hardware was only part of the invention. A machine needs a model it can understand, and that model must be sliced into thin layers, each described as paths for a laser, a nozzle or a print head. The triangle-mesh STL format associated with Hull’s company became the common way to hand a design from computer-aided design software to a printer, and slicing programs turned it into machine instructions. The idea of drawing layers one at a time had a precedent in pen plotters, which drew lines under computer control, and a 3D printer can be understood as a plotter that also moves in height.
So who built the first one?
A careful answer lists the contributions rather than picking a winner. Kodama published first, a French team filed a patent first, and Hull filed shortly afterward, then turned the concept into a commercial product. Others independently created powder, filament and sheet-based machines. Each is “first” in some sense, and the technology as we know it came from all of them together.