New Electrochromatic Lenses Rapidly Change Color
STORRS, Conn., July 13, 2011 — Quick-changing electrochromatic transition lenses have been created that use an electric current rather than polymers to change colors in films and displays when triggered by light. The new technology has captured the interest of the US military as a way to assist soldiers who need to see clearly in rapidly changing environments.
"This is the next big thing for transition lenses," said Greg Sotzing, a professor of chemistry at the University of Connecticut's College of Liberal Arts and Sciences and a member of UConn's Polymer Program.
The typical material behind a transition lens is what is called a photochromic film, or a sheet of polymers that change color when light hits them. Sotzing's new technology does things slightly different: His electrochromic lenses are controlled by an electric current passing through them when triggered by a stimulus, such as light.
A new lens material developed at UConn can change color and has attracted the interest of the US military. (Images: UConn)
"They're like double-pane windows with a gap between them," Sotzing said. He and his colleagues squirt a mixture of polymers — or as he calls it, "goop" — in between the layers, creating the lens as it hardens. The mixture of polymers used in this lens creates less waste and is less expensive to produce than previous mixtures, he said.
"The lifetime of sunglasses is usually very short," said Sotzing, who pointed out that people often misplace them. By making the manufacturing less expensive, commercial retailers will be able to produce more of them.
Another benefit of this material is that it can change colors as quickly as electricity passes through it, which is virtually instantaneously. This process could be very useful for the military, Sotzing said. For example, if a person emerges from a dark passageway and into the desert, a lens that would alter its color instantly to complement the surroundings could mean life or death for some soldiers.
"Right now, soldiers have to physically change the lenses in their goggles," he said. "This will eliminate that need." Sotzing will begin a one-year sabbatical at the Air Force Academy in August, where he hopes to develop some of these ideas.
Greg Sotzing, professor of chemistry.
In November 2010, partially based on work supported by the Center for Science and Technology Commercialization's Prototype Fund, a UConn R&D corporation, Sotzing and colleague Michael Invernale, now a postdoctoral researcher at MIT in Cambridge, founded a company called Alphachromics Inc. The university has a patent pending for this new technology, which is currently under option to the company. Alphachromics is also testing applications of these polymer systems for energy-saving windows and custom fabrics.
Currently in talks with manufacturers of sunglasses, Sotzing said that the world of Hollywood could have a market for this technology. He describes applications he calls "freaky," including colors that move back and forth across the glasses, evoking styles like those sported by Lady Gaga.
Sotzing did, however, stress that the best thing about this technology is the creation of business in Connecticut. Although the glasses won't be made here, the technology will be licensed out of the state and, he hopes, enable Alphachromics to continue to expand.
"We don't make the sunglasses," he said. "We make the formulation of what goes inside them."
For more information, visit: www.uconn.edu
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