Another in a series of articles on this topic from Singularity Hub: "The blind in Europe have reason to rejoice, the world's most advanced artificial retina has just received the CE Mark, approved for use in new patients. The Argus II, developed by Lawrence Livermore National Laboratory and marketed by Second Sight, is on sale in the EU, but still awaiting FDA approval here in the US. Luckily, clinical trials are already underway and we could get the amazing device here soon. With the Argus II, blind patients use an external camera to pick up video that is wirelessly transmitted to an electrode array surgically implanted in the eye. While full vision is not restored, the 60+ electrodes allow for some distinction of outlines and other basic shapes. Definitely an improvement over blindness. ... a camera embedded in a pair of glasses records the world in front of the patient. A wearable computer takes that image and transforms it into a basic series of impulses. That pattern is transmitted to the Argus II implant which rests inside the eye, and which is attached to the back of the eye through an electrode array. ... Although software improvements may arrive first, hardware upgrades are also on the horizon. The Argus II operates with about 60 electrodes in its array. That's 60 points of data for your eye to interpret. The Argus III, currently under development at LLNL, should have 200+ electrodes. Perhaps considerably more. It will take a thousand or so to make out human faces accurately, but the Department of Energy is pushing LLNL towards that goal, and beyond. As slow as the progress in artificial retinas has been, it shows no sign of stopping. There are other projects outside of the Argus series, at least two (one in MIT, another in Germany) show serious promise, and even have superior qualities to the Argus in some respects. I have no doubt that we could, eventually, reach a resolution that equals that of the human eye. Perhaps, with a different kind of interface, we could even see in greater detail than nature intended."

Link: http://singularityhub.com/2011/03/08/artificial-retina-that-lets-the-blind-see-again-more-great-videos-of-the-argus/