The artificial eyes use a camera and video processor mounted on sunglasses to send captured images wirelessly to a tiny receiver on the outside of the eye. In turn, the receiver passes on the data via a tiny cable to an array of electrodes which sit on the retina - the layer of specialized cells that normally respond to light found at the back of the eye.
When these electrodes are stimulated they send messages along the optic nerve to the brain, which is able to perceive patterns of light and dark spots corresponding to which electrodes have been stimulated. The hope is that patients will learn to interpret the visual patterns produced into meaningful images.
The bionic eye has been developed by US company Second Sight. So far 18 patients across the world have been fitted with the device. One totally blind man, who had seen total blackness for 30 years, reports being able to sort out socks by color, see white lines on the road, and more. The technology still a long way to go, but this is major progress.