Nanoprinting imprinting metalenses 100x faster than lithography.
Professor RHO Jun-seok from the Departments of Mechanical Engineering and Chemical Engineering at POSTECH has gained international attention for developing a mass-production process for metalenses and a switchable 2D-3D display technology based on them. The two studies were simultaneously published in the April 30 issue of Nature. This marks the first case in Korea of a researcher publishing two separate papers as corresponding author in the same issue of the journal.
A metalens is a flat optical device that controls light using nanoscale structures rather than curved glass. By replacing bulky glass lenses with engineered surface patterns, optical systems become far thinner and lighter. Because this enables control of light at scales smaller than its wavelength, metamaterials are often regarded as a Nobel Prize–worthy field of research.
The first study addressed a key barrier to commercialization: large-scale manufacturing. Production has so far relied on expensive and complex semiconductor fabrication processes due to the extreme precision required, making it slow, costly, and largely limited to laboratory research. To overcome this, Prof. RHO’s team developed a Roll-to-Roll Nanoimprint process enabling continuous production using a cylindrical roller. Instead of fabricating nanoscale structures one by one on rigid molds, flexible polymer molds were used to imprint patterns onto thin films. This shifts fabrication from a one-at-a-time process to continuous factory-scale production. The team produced over 300 metalenses per second, about 100 times faster than conventional methods, while maintaining consistent performance over a 200-meter process.
