A new ultrathin, flat lens focuses light without imparting the optical distortions of conventional lenses.
Image: Francesco Aieta
Can you imagine a microscope as thin as a dime—or maybe a pair of glasses with lenses thinner than a sheet of paper? 

Scientists have designed a new ultrathin flat lens that focuses light without imparting the distortions of conventional lenses. They say it eliminates optical aberrations, such as the “fish-eye” effect that results from conventional wide-angle lenses.

The ultrathin wafer of silicon and gold, created by applied physicists at the Harvard School of Engineering and Applied Sciences, is essentially two-dimensional at just 60nm thick. This new device operates at the range commonly used in fiber-optic communications and is completely scalable and simple to manufacture.

“In the future we can potentially replace all the bulk components in the majority of optical systems with just flat surfaces,” says lead author Francesco Aieta, a visiting graduate student from the Marche Polytechnic University in Italy. “It certainly captures the imagination.”

Aieta F, Genevet P, Kats MA, et al. Abberation-free ultrathin flat lenses and axicons at telecom wavelengths based on plasmonic metasurfaces. Nano Lett. 2012 Aug 21. [Epud ahead of print.]