Researchers at the Georgia Institute of Technology in the United States have created a corrective lens that tints on demand.
There are limitations to photochromic lenses. They do not always provide enough protection in very strong light and do not darken enough when worn behind the windshield of a car.
Wearers of the lenses designed by the U.S. researchers activate the colouring and go from one tint to another by pressing the electrical switch on the temple. The lenses are made with four electrochromic polymers. They blend together in reaction to the tiny electrical charge set off by the switch, thus darkening the lenses.
The researchers are convinced this innovation could easily be mass-produced.
To read more: http://www.optometry.co.uk/news-and-features/news/?article=6889
