3D Printer Uses Rays of Light to Shape Objects

摘要

Most 3D printers, including light-based techniques, build up 3D objects layer by layer. This leads to a "stair-step" effect along the edges. They also have difficulties creating flexible objects because bendable materials could deform during the printing process, and supports are required to print objects of certain shapes, like arches. Nicknamed the "replicator," a new 3D printer can create objects that are smoother, more flexible, and more complex than what is possible with traditional 3D printers. It can also encase an already existing object with new materials - for instance, adding a handle to a metal screwdriver shaft - which current printers struggle to do. The technology has the potential to transform how products from prosthetics to eyeglass lenses are designed and manufactured since customizable geometry can be added to a metallic component or something from another manufacturing process. The printer relies on a viscous liquid that reacts to form a solid when exposed to a certain threshold of light. Projecting carefully crafted patterns of light - essentially "movies" - onto a rotating cylinder of liquid solidifies the desired shape all at once. Basically, the system is an off-the-shelf video projector plugged into a laptop that projects a series of computed images while a motor turns a cylinder with a 3D printing resin in it. Subtleties include how the resin is formulated and how the images that are going to be projected are computed. Currently, the printer can make objects up to four inches in diameter.