A retinal implant - or bionic eye - which is powered by light has been invented by scientists at Stanford University in California. Implants currently used in patients need to be powered by a battery. The new device, described in the journal Nature Photonics, uses a special pair of glasses to beam near infrared light into the eye. This powers the implant and sends the information which could help a patient see. Diseases such as age-related macular degeneration and retinal pigmentosa result in the death of cells which can detect light in the eye. Eventually this leads to blindness.To see more details visit,www.bbc.co.uk