Experts have developed a novel lens coating set to liberate spectacle wearers who tend to struggle to see as moisture from their breath condenses on their glasses.
And anyone working in a steamy kitchen is also likely to be plagued by the problem.
Normally, when warm air hits the colder surface of a pair of glasses, water vapour condenses on the lenses as tiny droplets. But the new coating prevents the droplets from forming, meaning the condensed waters forms a thin layer over the lens instead and that layer is effectively invisible to the glasses wearer.
The lenses are available to customers at independent opticians and will cost an average of 25 pounds for the coating on a pair.
Essilor's coating uses a metal compound the firm is keeping secret for commercial reasons. A special alcohol-based liquid should be applied to the lenses weekly by wearers to maintain the layer.
"Our researchers are dedicated to exploring ways to make wearing glasses as close as possible to natural vision. Optifog represents a significant step towards achieving that goal," the Daily Mail quoted Mike Kirkley, managing director at Essilor as saying.