Image via Stanford University

Sight is the most relied upon of all the senses, alerting us to danger and allowing us to enjoy the beauty of a summer sunset. Unfortunately, millions of people live with impaired vision and as we get older, it’s almost guaranteed that we’ll experience further vision loss.

What’s interesting is that even when age or disease-related, blindness isn’t caused by a “broken” eye. Usually it’s just the cells of the retina that convert light into electrical pulses dying off. In most cases the nerves that process what our eyes see and send those images to the brain are still intact, and, if we could find a way to replace the dead retina cells, would continue to work.

To test this theory, researchers at Stanford University developed a photovoltaic prosthesis that could be implanted directly into the eye and used to convert light into electrical currents. In the Stanford system, a video-camera worn by the patient would transmit images to a processor, which would then displays the image inside a special set of LCD glasses. The LCD display would then use infrared light pulses to project the image onto photovoltaic cells implanted underneath the retina. The cells would convert those light signals into electrical impulses that in turn stimulate the retinal neurons above them.

Engineered at the Stanford Nanofabrication Facility, this is also the first flexible implant, using tiny silicon bridges to fold over the shape of the eye. “The advantage of having it flexible is that relatively large implants can be placed under the retina without being deformed, and the whole image would stay in focus,” said Associate Professor of ophthalmology Daniel Palanker.  The flexible implants are also able to cover an even larger portion of the retina, allowing patients to see the entire visual field presented on the display.

While it’s not going to provide the blind or elderly with perfect vision anytime soon (the best most current systems can achieve is somewhere around 20/1,200 vision, and none offer color images) it represents a hopeful future for those who long to see the world around them. And because it’s self-contained, powered by light, and portable, it will allow patients to avoid the bulky devices and tangle of wires used in the past.

[via ArsTechnica]