From New Scientist – Health:
Eberthart Zrenner and colleagues at the University of Tübingen in Germany have developed a microchip carrying 1500 photosensitive diodes that slides into the retina where the photoreceptors would normally be. The diodes respond to light, and when connected to an outside power source through a wire into the eye, can stimulate the nearby nerves that normally pass signals to the brain, mimicking healthy photoreceptors.
The team reports that their first three volunteers could all locate bright objects. One could recognise normal objects and read large words. …
…. As a safety precaution, the implants in this first pilot study were removed after several weeks, says Walter Wrobel, head of Retina-Implant, a company based in Reutlingen, Germany, formed by the researchers to eventually market the implant. “Based on the results of this study, we have designed a new system, which is being implanted permanently, or as long as patients like it.”
In the new system, the power source connects to the retinal implant via a mechanical coupling through intact skin, not via a wire through an incision in the skin as the earlier system did. “That means they can shower easily, leave the hospital and go around town on their own,” says Zrenner. “They can go out for a meal, and really see things, like a nice glass of beer.”