Engineers at the University of Utah have developed a new method of creating optics which are flat and ultra-thin, yet can still bend light to a single point like traditional lenses. It's hoped the breakthrough could see some cameras using paper-thin lenses within the next five years.
The research, led by professor Rajesh Menon of the Department of Electrical and Computer Engineering, challenges the view that flat, diffractive lenses cannot be corrected for all colors simultaneously. Typically, diffractive lenses bend different wavelengths differently, leading to large chromatic aberrations.
However, the engineers have created a super-achromatic lens 10 times thinner than the width of a human hair, which uses a microstructure-geometry to bring different wavelengths to the same focus. As such, future lenses developed with the method could replace the traditional bigger and curved lenses we're used to seeing on cameras.
"We came up with a new method of designing the lens so as to drastically reduce such aberrations," professor Menon told Gizmag. "In other words, our algorithm is able to design a microstructure-geometry that is able to bring different colors (wavelengths) to the same focus."
He added that the way in which the lenses can be produced, which can be made out of any transparent material such as glass or plastic, gives them an advantage over other flat lens approaches such as meta-lenses, which are harder to manufacture. "We fabricated our lenses using optical lithography," Menon said. "But, these devices are very easy to manufacture at low cost via the same technologies used to make CDs or DVDs."
The team admits further work is needed before the new lenses can deliver the image quality needed to replace conventional lenses. However, Menon suggests they could be used in simple commercial applications within the next five years. The team is focused on applications in smartphone cameras, cameras that can be mounted on drones, and medical devices, where size and weight it paramount.
The research has been published in the journal Scientific Reports.
Source: University of Utah