Distortion-Free Photos Possible With Flat Lens
A new ultrathin, flat lens focuses light without imparting the optical distortions of conventional lenses.
CREDIT: Francesco Aieta
A new ultra-thin flat lens could allow cameras to one day take distortion-free photos, researchers say.
Unlike typical camera lenses, which are made from curved glass, the new flat lens is made using a very thin wafer of silicon that is only 60 nanometers thick.
“Our flat lens opens up a new type of technology,” Federico Capasso, a physicist at the Harvard School of Engineering and Applied Sciences, said in a statement.
“We’re presenting a new way of making lenses … It’s extremely exciting.”
Curved glass lens can capture light from any angle and focus it into a single point, but they can also produce distortions such as the “fish-eye” effect that is common in photos taken with conventional wide-angle lenses.
To get around such problems, the new flat lens created by Capasso's team uses a series of small nano sensors – which the researchers dubbed "nanoantennas" – that refract incoming light so that it ends up on the same focal plane.
“What we’ve done is create an artificial refraction process,” Capasso said.
For now, the nanoantennas can only focus one wavelength of light, but the team is looking into antennas that can handle normal white light, which is made up of multiple wavelengths.