The BBC's Inside Out London has been speaking exclusively to one of just three people in the UK to have been fitted with a 'bionic eye', blind patient 73-year-old Ron, who is able to see for the first time in 30 years.
Ron had the experimental surgery in summer 2008 at Moorfield's eye hospital and has made good progress since.
Ron who lost his sight in his 40s due to retinitis pigmentosa now has the ability to see flashes of coloured light and dark.
His treatment is part of an international trial carried out be an American company called Second Sight and he is one of the 18 patients across the world who taking part in the experiment.
Here is an explanation of how the 'eye' works after it has been implanted.