A new 3D printing method using light, being developed by University of Michigan, could produce 3D printed prototypes 100 times faster than conventional means. The method uses two lights to control where the liquid resin hardens and where it remains fluid. The method allows for more complicated 3D prototypes because they aren't relying on building the prototype one dimension at a time. By controlling the resin, they are able to produce a true 3D printed object.
“It’s one of the first true 3D printers ever made,” said Mark Burns, professor of chemical engineering and biomedical engineering at University of Michigan.
From the University of Michigan article "By creating a relatively large region where no solidification occurs, thicker resins—potentially with strengthening powder additives—can be used to produce more durable objects. The method also bests the structural integrity of filament 3D printing, as those objects have weak points at the interfaces between layers.
An earlier solution to the solidification-on-window problem was a window that lets oxygen through. The oxygen penetrates into the resin and halts the solidification near the window, leaving a film of fluid that will allow the newly printed surface to be pulled away.
But because this gap is only about as thick as a piece of transparent tape, the resin must be very runny to flow fast enough into the tiny gap between the newly solidified object and the window as the part is pulled up. This has limited vat printing to small, customized products that will be treated relatively gently, such as dental devices and shoe insoles.
By replacing the oxygen with a second light to halt solidification, the Michigan team can produce a much larger gap between the object and the window—millimeters thick—allowing resin to flow in thousands of times faster."
Read more about using light for faster prototypes at University of Michigan.