Researchers working on eyeglasses that change into sunglasses on command

A new type of eyeglass lens that rapidly darkens when desired, eliminating the need to passively wait for light changes in one's surroundings would soon to become a reality, researchers at the Georgia Institute of Technology in the US claimed.

Photochromic or transitional lenses that are available in the market have considerable limitations and fail to darken inside cars of under caps.

Also several brands allow harmful rays to seep through and it also take time for them to clear up when the sun disappears, which poses inherent safety implications.

A Georgia Tech research team added a small electrical charge that lends the magic touch enabling switching from clear to dark and back again in seconds, enabling the capacity for fine colour tuning.

The researchers said any colour in the entire range of hues in which sunglasses were commercially available was possible. According to the researchers, their method could be easily applied for retail versions.

The paper has been published in American Chemical Society Applied Materials & Interfaces.

Meanwhile, according to  media report, researchers at the Georgia Institute of Technology in Atlanta, Clayton State University, Georgia, and the BASF Corporation had created a strategy to create a wide variety of colours in lenses with the use of electrochromic polymers.

The polymers reversibly changed colour when a burst of electric charge is applied. The researchers have created several shades of brown electrochromic polymers by using various combinations of cyan, yellow, orange, and periwinkle blue.

The eyeglasses they create use the polymers that provide a rapid high-contrast change from colourless to dark or back again, a process that took only seconds. They also showed that the method could be used in large scale manufacturing.

The eyeglasses that change rapidly to sunglasses and back again could be used by drivers, airline pilots and police among others.