Researchers at the Vienna University of Technology have perfected 3D technology using two-photon lithography that can print orders of magnitude faster and smaller than similar devices. The 3D printing process uses a liquid resin, which is hardened at precisely the correct spots by a focused laser beam. The focal point of the laser beam is guided through the resin by movable mirrors and leaves behind a hardened line of solid polymer a few hundred nanometers wide.
This fine resolution enables the creation of intricately structured sculptures as tiny as a grain of sand. “Until now, this technique used to be quite slow”, says Professor Jürgen Stampfl from the Institute of Materials Science and Technology at the TU Vienna. “The printing speed used to be measured in millimeters per second — our device can do five meters in one second.”
In just 4 minutes it can print 100 layers consisting of 200 lines per layer. That translates into five meters of polymer printed in one second. In two-photon lithography, this is a actually a world record.
At the TU Vienna, scientists are now developing biocompatible resins for medical applications. They can be used to create scaffolds to which living cells can attach themselves facilitating the systematic creation of biological tissues. The 3d printer could also be used to create tailor made construction parts for biomedical technology or nanotechnology. But for now, the researchers are having fun creating models of racing cars, a model of St. Stephen’s Cathedral in Vienna, and the Tower Bridge in London.