Scientists at the the National Research Foundation (NRF) in South Korea have developed a technology to wirelessly charge smart contact lenses for continuous operation.

The team of scientists led by Park Jang-ung, a materials science professor at Yonsei University in Seoul, used ultrafine printing methods to build a supercapacitor, rectifying circuits and a light emitting diode inside a soft contact lens.

A supercapacitor is capable of rapidly charging and discharging electronic devices and is a key part of very small wearables that cannot use an internal battery.

The capability to make very fine and durable key components could lead to all sorts of innovations and contribute to the development of new types of smart wearable devices in the future.

"The smart lens created is flexible like any other ordinary contact lens, with its circuitry being used to check various biomarkers in a person's tears, and easily allows the wearer to experience augmented reality on par with science-fiction movies," NRF said. It stressed that this arrangement is comfortable and does not affect the wearer's vision.

Since the contact can be wirelessly charged, there is no need for a plug-in power port that can lead to safety issues and foreign objects getting inside the lens and affecting the circuitry. It said tests have shown there is no real rise in heat during the charging process, which is often a problem with wireless devices, and the lens can be stored in normal contact solutions, with no deformation being detected over time.

The research has been published in the latest issue of the international journal Science Advances under the title "Printing of wirelessly solid-state supercapacitors for soft, smart contact lenses with continuous operations."