This is a huge miracle in the history of medical science. Surgeons have successfully implanted "bionic eyes" in two blind patients, in an attempt to restore some of their vision. The device -- the first of its kind -- incorporates a video camera and transmitter mounted on a pair of glasses. This is linked to an artificial retina, which transmits moving images along the optic nerve to the brain and enables the patient to discriminate rudimentary images of motion, light and dark.

The Argus II uses a video camera to capture images. These are converted into electrical signals, which are transmitted wirelessly to the implant behind the retina. The electrodes in the implant unscramble the signal to create a crude black-and-white picture that is relayed along the optic nerve to the brain. The brain can then perceive patterns of light and dark spots corresponding to the electrodes stimulated.
Surgeons give hope to blind with successful 'bionic eye' operations

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