Who would have thought that the future of biometric security systems would involve cows shooting lasers out of their eyes? That does, however, describe work being carried out by researchers at the University of St. Andrews in Scotland. They’ve developed ultrathin, bendable laser stickers which can be adhered to an eyeball, via contact lens — as shown in a recent demo using a cow’s eye. Because the laser lenses can be made to emit a well-defined combination of several wavelength of laser light, they could potentially be useful for authentication technology.
“A number of years ago, I published work on turning individual living cells into tiny, microscopic lasers,” Malte Gather, a physics professor who worked on the project, told Digital Trends. “The initial idea back then was to investigate if biological systems are capable of producing laser light since this is not observed in nature. One of the reporters picking up on the story joked that the next thing this would develop into would be superheroes shooting deadly laser beams out of their eyes, just like in popular comic books. When we realized that we may have a way to make laser stickers, I remembered this comment and we decided to run some tests sticking our lasers onto contact lenses and onto cow’s eyes.”
The ultrathin lasers are made up of only two layers of two different materials, with a total thickness of about 1/5000th of a millimeter. The laser is made from an organic semiconducting polymer, much like the films which activate the pixels in a smartphone display. This polymer fluoresces when it is exposed to light, which in turn powers the laser. In tests involving the cows’ eyes, the contact lenses were able to emit a green laser beam onto a screen positioned 50 centimeters away.
As Gather notes, eyes and lasers are not usually BFFs, but these lasers are so low-powered that they can be safely operated while they are in direct contact with the eye. “In practice, this would again be a convenient way for access control and authentication — one would have a device that performs a biometric iris scan, and in parallel reads out the wavelengths of light emitted by a laser worn by the same individual,” he continued.
A paper describing the work was recently published in the journal Nature Communications.