Through manufacturing techniques including microfabrication and self assembly, researchers at the University of Washington were able to construct a contact lens with an imprinted electronic circuit and lights, which is biologically safe for users.
Most recently, tests were conducted to ensure the polymer substrate used in the lens would not affect a biological organism. The lenses were tested on rabbits for twenty minutes, after which they showed no negative reactions to the lenses. “That is something we have to do and be very careful about so we don’t damage the eye of the person or the animal under study,” says Babak Parvis, assistant professor of electrical engineering at the University of Washington.
Ultimately these devices would allow users to view and navigate information displayed directly on their cornea. “This is unprecedented; nobody has been able to or even attempted to dynamically construct images right on the surface of the eye,” says Parvis. “We have a lot of things to look into and a lot of technical problems to solve.”
The lens will not obstruct the user’s vision because most of the obstructive circuitry would sit on the iris, outside the viewable area of the eye. “We started by really evaluating what might be possible from the contact lens point of view, in terms of synthesizing the circuitry and functions and sensory, so it’s really exciting to see some prototype being produced and tested,” says Tueng Shen, assistant professor in ophthalmology at the University of Washington.
The lenses have been equipped with an antenna that can be used to harvest radio frequency energy and eventually will power the devices, though recent tests were passive. Parvis hopes to eventually harvest light but the key to supplying the lenses with power is by absorbing wireless or ambient energy.
Once fully functional, these lenses lend themselves to mass production because of the methods already used in their assembly. “I have no doubt that we can eventually mass produce these, but before we go to that point to attempt to mass produce any of these, we have to obviously generate all the functions that we would like on the lens and then test it extensively to make sure it is safe,” he says.