World’s smallest 3D-printed wine glass has a rim smaller than hair

As such, it can be “used for customized lenses for medical machinery that perform minimally invasive surgery, micro-robots that navigate extreme environments, or filters and couplers for fiber optic networks, to name a few applications.”

Fiber optic filters

The work delivered one of these fiber optic filters, showing that the technique can print devices directly on the tip of an optical fiber as thin as a strand of human hair.

“The backbone of the internet is based on optical fibers made of glass. In those systems, all kinds of filters and couplers are needed that can now be 3D printed by our technique,” said co-author Kristinn Gylfason, an associate professor of Micro- and Nanosystems at KTH. “This opens many new possibilities.”

Even better, the new technique does not require significant energy to 3D print silica glass, which under normal conditions sees materials heated up to several hundred degrees for hours, added the study’s lead author, Po-Han Huang, a doctoral student at KTH.

 “The advantage of our method is there’s no need for thermal treatment, and the glass can withstand extreme heat in applications.”

The result is a method to produce silica glass using readily available commercial materials.

The researcher also explained that eliminating the need for thermal treatment allows the technique to be used widely in various application scenarios.

 “The concerns when integrating 3D printing methods are usually different for different applications. Even though optimization of our method is still required for different applications, we believe our method presents an important and necessary breakthrough for 3D glass printing to be used in practical scenarios,” he said.

The only question remains whether the wine glass is the world’s smallest. According to the researchers, it is.

“Definitely nobody has 3D printed a wine glass that consists of glass as-printed,” Niklaus concluded in the statement.

The study is published in Nature Communications.

Study abstract:

Silica glass is a high-performance material used in many applications such as lenses, glassware, and fibers. However, modern additive manufacturing of micro-scale silica glass structures requires sintering of 3D-printed silica-nanoparticle-loaded composites at ~1200 °C, which causes substantial structural shrinkage and limits the choice of substrate materials. Here, 3D printing of solid silica glass with sub-micrometer resolution is demonstrated without the need of a sintering step. This is achieved by locally crosslinking hydrogen silsesquioxane to silica glass using nonlinear absorption of sub-picosecond laser pulses. The as-printed glass is optically transparent but shows a high ratio of 4-membered silicon-oxygen rings and photoluminescence. Optional annealing at 900 °C makes the glass indistinguishable from fused silica. The utility of the approach is demonstrated by 3D printing an optical microtoroid resonator, a luminescence source, and a suspended plate on an optical-fiber tip. This approach enables promising applications in fields such as photonics, medicine, and quantum-optics.