Researchers, including one of Indian-origin, have developed a stretchable nano-scale device that manipulates light to such an extent that it can filter specific colours while still being transparent and could be used to make 'smart' contact lenses.
Using the technology, high-tech lenses could one day filter harmful optical radiation without interfering with vision - or in a more advanced version, transmit data and gather live vital information or even show information like a head-up display, researchers from University of Adelaide and RMIT University in Australia said.
The light manipulation relies on creating tiny artificial crystals termed 'dielectric resonators', which are a fraction of the wavelength of light - 100-200 nanometres, or over 500 times thinner than a human hair.
"Manipulation of light using these artificial crystals uses precise engineering," said Withawat Withayachumnankul from University of Adelaide.
"With advanced techniques to control the properties of surfaces, we can dynamically control their filter properties, which allow us to potentially create devices for high data-rate optical communication or smart contact lenses," said Withayachumnankul.
The devices are made on a rubber-like material used for contact lenses, researchers said.
"We embed precisely-controlled crystals of titanium oxide, a material that is usually found in sunscreen, in these soft and pliable materials. Both materials are proven to be bio-compatible, forming an ideal platform for wearable optical devices," said Madhu Bhaskaran from RMIT.
"By engineering the shape of these common materials, we can create a device that changes properties when stretched. This modifies the way the light interacts with and travels through the device, which holds promise of making smart contact lenses and stretchable colour changing surfaces," she added.
"With this technology, we now have the ability to develop light weight wearable optical components which also allow for the creation of futuristic devices such as smart contact lenses or flexible ultra-thin smartphone cameras," said Philipp Gutruf from RMIT.
The findings were published in the journal ACS Nano.
