1. Hideo Kodama, the Japanese Researcher Who Invented Early 3D Printing Technology
One of the earliest examples of the basic technology behind 3D printing was invented by a Japanese researcher. In 1980, Hideo Kodama, a researcher at the Nagoya Municipal Industrial Research Institute, developed a method called "stereolithography." He got the idea from a machine he saw at an exhibition that made printing plates for newspapers. His invention involved stacking resin that hardens only where light hits it, building up a 3D shape layer by layer. This is considered one of the earliest examples of this stacking method.[1]
However, the idea of making 3D objects with light-hardening resin or powder had already been patented overseas before Kodama’s work. Kodama did apply for a patent, but according to his own explanation, he failed to complete the necessary procedures afterward. He said that after changing jobs to become a patent expert, he lost interest in his own invention. He said he first learned years later, while doing research for a trading company, that the deadline for the procedure had passed.[1] [5]
2. Chuck Hull, the American Who Patented Stereolithography in 1984
Four years after Kodama’s invention, in 1984, Chuck Hull in the United States applied for a patent using the same "stereolithography" mechanism.[2] Hull co-founded the company 3D Systems in 1986. In 1987, the company released the "SLA-1," which was the world’s first commercial 3D printer.[2] Because of this, it was an American company that spread this technology to the world along with the name "3D printer."
3. How Stereolithography (SLA) Hardens Liquid Resin with Ultraviolet Light
The "Stereolithography" (SLA) method works by shining invisible light (ultraviolet light) on liquid resin. Only the spots where the light hits become hard. After hardening one layer, the printer lowers the platform slightly and shines light on the new surface to harden the next layer. By repeating this hundreds or thousands of times, a 3D shape is built up little by little.[3] This method is known for producing smooth surfaces and accurately reproducing fine details.
4. How Fused Deposition Modeling (FDM) Melts Plastic Thread and Stacks It
After the SLA method, Scott Crump in the United States invented a different method called "Fused Deposition Modeling" (FDM). This method melts plastic thread (called filament) with heat and pushes it out of a thin nozzle, stacking it layer by layer to build the object.[4] Crump and his wife founded the company Stratasys. They applied for a patent for this technology in 1989.[4]
The patent for FDM expired around 2009, after the 20-year period from the application ended. The expiration is thought to be one of the triggers that let many companies build FDM printers freely, which is considered to have helped lower prices. That, in turn, is thought to have been one factor in 3D printers spreading to schools and homes.
5. How a 3D Pen Differs from a 3D Printer by Drawing in the Air
Most 3D printers are machines that stack material on a platform; they are not designed to draw directly in the air. However, there is a separate tool called a "3D pen." It works similarly to the FDM method, melting plastic and pushing it out from the pen tip. With a 3D pen, you can actually draw lines in the air to create 3D shapes.
6. Ways You Can Investigate 3D Printing Yourself
If you want to learn more about 3D printers, here are some things you can do today. You can try making 3D objects by stacking thin layers of clay or paper. Try stacking them from the bottom up, just like a 3D printer does.
When you are curious, write down just one word or question that interests you. It can be a starting point for further research. For example, you could write down: "Hideo Kodama developed a method for hardening resin with light in 1980."