Bionic Contact Lenses

Is bionic vision in your future? It might be if engineers can perfect a contact lens filed with electronics. As this ScienCentral News report explains, engineers have demonstrated how to put electronics inside a contact lens.

Super Contacts

You’ve seen the TV shows and movies, someone implanted with electronic devices that give them super human powers, including super vision. In reality, the best we can do is a set of binoculars, or strap-on night vision goggles. But that all could change as engineers work to supercharge contact lenses.

“If you look at the structure of a contact lens,” says Babak Parviz, University of Washington assistant professor of eleectrical engineering, “ more or less it’s just a polymer that … does vision correction.”

Since the group was already working on incorporating micron-scale devices onto unconventional substrates including plastics, he says, “we saw the opportunity to integrate these on a contact lens.”

Parviz adds that much of the micro technology that would have to fit on a contact lens is already available and says, “To look at the semi-conductor industry and what we have in opto-electronics and micro machines, we already have a lot… (but) one thing we have not done is to put those things on a contact.”
Parviz imagines a whole list of things a supercharged contact lens might do, explaining, “I can see this exponentially growing and having many, many applications; from lenses that are quote-unquote intelligent and can help the user who’s had a cataract surgery to see better, to amplified vision, to all sorts of gaming applications and interfacing with your iPod and lots of things.”
Parviz says reaction to the the lens has been good; that imaginations are excited and that people are volunteering to test it now. However, he cautions that his group so far has only demonstrated that the electronic circuits can be assembled in a contact and that the contact so far appears safe when tested on a rabbit. At this point they have not yet even powered up the lens, so operational models are still some time away.

But the bionic contact’s biggest contribution might not be in looking out, but looking in. “We see the eye not only as our window to the outside world, but actually a window into the body also,” explains Parviz. He says, “A lot of biomarkers of interest do actually show up on the surface of the eye.

So, if you could have a contact lens that could sample what’s happening on the surface of the eye, detect various targets, molecules of interest, and relay the information out wirelessly, what you can do is to continuously monitor the health situation of a person.” Such continuous monitoring in a hospital might lessen the need for blood samples; at home a diabetic might get an instant warning when blood sugars go to high or low.

Unlike its fictional counterpart that is somehow hard wired into the body, Parviz envisions some sort of wireless communication between the contacts and some device controlling it.

Anybody who has soldered electronic components together may wonder, how can all these electronics be put into a contact lens in a manner that is safe to go in an eye? Parviz says they avoid the heat and caustic chemicals of traditional electronic assembly by employing an element of self assembly. He says, “So what we do is that we make all of the components that we need to assemble into the contact lens independently…they come as a powdered… collection of components and then later on we self assemble those onto a contact lens to form our own system.”

One big challenge the engineers face is how to get power to run the electronics. Right now they’re exploring using coils that harvest radio frequency energy. Andrew Lingley, a graduate student in Parvaz’ lab, is working through the engineering problems. He says, “The idea is somewhat similar to transferring power to a speaker. So, in a speaker you have a coil of wire and you run a current through that wire. And, it sets up a magnetic field that is transferred to the moveable part of the speaker.” In his experiments he has a large coil that creates a magnetic field. When the lens is inside that magnetic field, the coils in the lens generate electrical current.

The research was presented in January 2008 at the Institute of Electrical and Electronics Engineers’ International conference on Micro Electro Mechanical Systems and was funded by the National Science Foundation and the Technology Gap Innovation Fund from the University of Washington.

Original here