Smart contact lenses power up

Flexible contact lenses that incorporate supercapacitors and wireless-charging components are now possible, thanks to newly formulated printable inks that serve as the electrode and electrolyte. Researchers in the Republic of Korea showed that a specific mixture of carbon molecules, polymers and solvent can be used to print a supercapacitor’s electrodes onto a lens with micron-scale precision via a technique called direct ink writing. The same process deposits a UV-cured ionic liquid that functions as the supercapacitor’s electrolyte. As a proof-of-concept, the work could one day lead to smart contact lenses with sensors for health monitoring, or with integrated displays for augmented reality applications (Science Advances 10.1126/sciadv.aay0764).