BBC: Oxford Eye Hospital and King's College Hospital in London, UK carry out clinical trials implanting 1,500-pixel sensors into the eyes of two blind patients. When light enters the eye and reaches the 3 sq. mm chip, it stimulates the pixels which sends electronic signals to the optic nerve and from there to the brain. The chip can have its sensitivity altered via an external power unit which connects to the chip via a magnetic disc on the scalp. The implant was developed by a German company, Retina Implant AG. The patients are now able to perceive light and even some shapes.
Thanks to CDM for the link!