Smart Lenses Will Do More Than Just Improve Your Vision
Some forty million Americans wear contact lenses, but imagine if those lenses could do more than just bring the outside world into focus?
There are scientists working on the next generation of contact lenses, so called “smart lenses”, and the potential is pretty amazing.
These are so called smart lenses, packed with circuits, sensors, and wireless technology.
“There’s a possibility to develop a really, really important new tool for medicine,” says Smart Lense developer Babak Parviz. He’s testing a smart lens that could one day replace the standard blood test. “It allows for a very non-invasive, continuous monitoring of the human body.”
Parviz believes bio-markers found in the blood, such as cholesterol, sodium, potassium and glucose can all be found on the surface of the eye.
One lens can monitor glucose and radio out the result. “Someday maybe you can read the result with your cell phone.”
Kim carter has Type 1 diabetes and pricks her finger 5 to 7 times a day. “I hate it,” says Kim, “it hurts.” So, she says she would definitely try it out if one became available on the market.
Smart Lenses as Medical Indicators
A team at the University of Maryland has developed a patented technology for monitoring blood glucose with contact lenses that change color as a function of blood sugar levels. The lenses have a sensor spot on the surface that detects the amount of glucose present in tears. If the sensor is inside the pupil zone, the wearer can detect the color change. When placed in the periphery of the lens, the wearer can see the change in a mirror.
The developer reports that sensing a change in glucose levels through tears lags about 30 minutes behind a change in the blood. The always-present monitoring may surpass the average of four times daily blood assessment by way of actual blood testing. The system may be advantageous for patients who require testing by a caretaker.
It is anticipated that this technology will only add a small incremental cost to current disposable lenses because the fluorescent sensor can be imprinted on lenses without any process changes in the overall manufacturing.
Another researcher, Sanford Asher, Ph.D., professor of chemistry at the University of Pittsburgh, is studying how “photonic crystals” can be incorporated in contact lenses to measure the presence of glucose in the tears, which would correlate to blood sugar levels. The photonic crystal is a gel made up of a proprietary combination of boronic acid and other chemicals. The chemicals form an array of long polymer chains, which contain receptors that bind to the structure of glucose. The spacing between the chains in the array changes as it comes into contact with glucose to cause a varying spectral refraction: high glucose results in a purple color, low glucose produces a reddish color and normal glucose levels produce a green color.
Some new lenses don’t just monitor disease. They treat it.
Dr. Joe Ciolino is a doctor at mass eye and ear infirmary: “The lens has the ability to release medication to the eye for a long period of time.”
Harvard researchers are also testing such a device. A light brown donut shape in the center of this lens contains a drug. Dr. Dan Kohane of Children’s Hosptial, Boston adds, “The object would be placed in the eye and would slowly leak out over time” thereby delivering the medication.
Perhaps the most amazing idea for a smart lens is this one: Tiny LEDs built into the lens overlay images into your field of vision. The idea is that one day you would be able to stream health data, the internet, even television, right in front of your eyes.
Smart Lenses as Wearable Computers
Consumers have a big appetite for interactive entertainment and information and, yet, endure small consoles like iPhones and iPads as their visual portals. The iMax theater experience is one evidence in the “bigger is better” enjoyment of media that is appreciated by consumers. It is forecasted that consumers will continue to search for hands-free immersive methods for accessing visual media. The foreseeable end of this search is in wearable information sources. Researchers at the University of Washington are attempting a new generation of wirelessly powered lenses with tiny circuits, light emitting diodes and built-in electronics.
The team admits the limited function presently but forecasts what is possible with the technology. Even so, team leader Babak Parviz, M.S., Ph.D., is optimistic in saying, “What we’ve done so far barely hints at what will soon be possible with this technology.” The researchers intend to turn a lens into a functional system by integrating control circuits, communication circuits and miniature antennas into the lens using custom-built optoelectronic components. While they have only accomplished an 8x8 LED array, the components will eventually include hundreds of LEDs, to form a more rich image on the retina. These components will need to be transparent and have an index of refraction of the lens polymer to avoid the effects of diffraction and refraction within the pupil when the content is not being displayed, or they will need to be miniaturized. Their goal is an array of 3600 10-µm-wide pixels spaced 10 µm apart. The content information will be provided to the control circuit of the lenses by portable devices used for regular displays. The team is challenged to make the lens of biocompatible materials and ultimately with passive pixels to reduce the power draw.
That appeals to grad student Matt Davis: “You could be reading your emails when you walk down the street, things like that.”
Just watch out where you walk!
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By Paula Ebben, WBZ-TV