Printing three dimensional objects with incredibly fine details is now possible using "two-photon lithography". With this technology, tiny structures on a nanometer scale can be fabricated. Researchers at the Vienna University of Technology (TU Vienna) have now made a major breakthrough in speeding up this printing technique: The high-precision-3D-printer at TU Vienna is orders of magnitude faster than similar devices (see video). This opens up completely new areas of application, such as in medicine.
Setting a New World Record
The 3D printer 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 polymerized line of solid polymer, just a few hundred nanometers wide. This high 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 two-photon lithography, this is a world record.This amazing progress was made possible by combining several new ideas. "It was crucial to improve the control mechanism of the mirrors", says Jan Torgersen (TU Vienna). The mirrors are continuously in motion during the printing process. The acceleration and deceleration-periods have to be tuned very precisely to achieve high-resolution results at a record-breaking speed.
Photoactive Molecules Harden the Resin
3D-printing is not all about mechanics – chemists had a crucial role to play in this project too. "The resin contains molecules, which are activated by the laser light. They induce a chain reaction in other components of the resin, so-called monomers, and turn them into a solid", says Jan Torgersen. These initiator molecules are only activated if they absorb two photons of the laser beam at once – and this only happens in the very center of the laser beam, where the intensity is highest. In contrast to conventional 3D-printing techniques, solid material can be created anywhere within the liquid resin rather than on top of the previously created layer only. Therefore, the working surface does not have to be specially prepared before the next layer can be produced (see Video), which saves a lot of time. A team of chemists led by Professor Robert Liska (TU Vienna) developed the suitable initiators for this special resin.
Researchers all over the world are working on 3D printers today – at universities as well as in industry. "Our competitive edge here at the Vienna University of Technology comes from the fact that we have experts from very different fields, working on different parts of the problem, at one single university", Jürgen Stampfl emphasizes. In materials science, process engineering or the optimization of light sources, there are experts working together and coming up with mutually stimulating ideas.
Because of the dramatically increased speed, much larger objects can now be created in a given period of time. This makes two-photon-lithography an interesting technique for industry. At the TU Vienna, scientists are now developing bio-compatible 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.
Vienna University of Technology: http://www.tuwien.ac.at/tu_vienna/
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Microsoft expands ad-free Bing searches for US schools from kindergarten through 12th grade
Google's 'Street View' maps add digital time capsules to provide visual retrospectives
AT&T plans to expand its gigabit Internet offering -- with a blazing Internet speed similar to Google Fiber -- to 21 new metro areas
We have video phone calls and a wealth of information at our fingertips, but no personal jet packs or moon colonies
Here's a short message to smartphone makers before you try to wow us with a bunch of glitzy features in your next device: Don't do it.
A lighting system that combines white LEDs with nanoparticles can mimic a natural sunny day, even when the skies outside are grey and gloomy
Approximately 18.1 percent of all US households with a Netflix or Hulu account are considered to be “cord cutters” or Internet consumers that lack cable or satellite television, according to a report by Experian Marketing Services. This includes independent young adults who have never paid for TV services.
Several bio-tech companies are developing exoskeletons that give people superhuman abilities. But these robotic suits are also doing something simpler: They're helping paralyzed veterans walk again.
An iPad accessory launching later this year will bring transparent morphing buttons to the device’s screen to aid touch-typing.
It runs, it jumps, it kicks a soccer ball -- but there's still work needed to remove the "creepiness" factor, says Honda