Gold-based coating prevents fogging in eyewear, car windshields

Researchers at ETH Zurich have developed an ultrathin, gold-based transparent coating that is able to convert sunlight into heat.

It can be applied to glass and other surfaces to prevent them from fogging, notes a press communique from the University. Applications for the new coating include eyewear, car windshields.

Researchers in the group led by ETH Professors Dimos Poulikakos and Thomas Schuizius point out that their coating is fabricated with methods which are used extensively in manufacturing. In aclean room and using vapor deposition under vacuum, minute amounts of gold are deposited onto the surface. ETH Zurich has applied for a patent on the coating.

What's special about the new coating is that it absorbs solar radiation selectively. Half of the energy contained in sunlight resides in the infrared spectrum, the other half in the visible light and UV radiation spectrum. Our coating absorbs a large proportion of the infrared radiation, which causes it to heat up by up to 8 degrees Celsius,” explains ETH doctoral student Iwan Hachler, who was a driving force behind the development. It absorbs only a minor fraction of the radiation in the visible range, which is the reason why the coating is transparent.