Ten blind people in the UK are set to be given "bionic eyes" for free by the National Health Service (NHS) as part of a pioneering treatment program. 
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The Argus II Bionic Eye, made by the company Second Sight, could mean a whole new world of vision for people previously blind through an inherited degenerative disease called retinitis pigmentosa -- and potentially pave the way for the technology to enter the mainstream. 。

The eyes are essentially retinal implants which translate images from a tiny video camera within a pair of eyeglasses worn by the patient into electrical pulses and eventually signals that reach the brain. Electrodes attached to the retina stimulate its remaining cells, which send information on to the brain. 。

A total of 10 people, five patients at Manchester Royal Eye Hospital and five at Moorfields Eye Hospital in London, will receive bionic eyes from the NHS throughout 2017, and they'll be monitored for a year to see how things move along. 。

Earlier trials have been pretty successful. "It surpassed all of our expectations when we realized that one of the retinitis pigmentosa patients using the bionic eye could identify large letters for the first time in his adult life," Professor Paulo Stanga of Manchester Hospital told the BBC.  。

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#ArgusII #bioniceye is world's first approved device intended to restore vision to the blind https://t.co/MAAnt9dL1g pic.twitter.com/W9BTubu4qA
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— Second Sight (Argus_BionicEye) February 12, 2016。

In fact, for some of the patients, the bionic eyes have already made quite a difference. "Having spent half my life in darkness, I can now tell when my grandchildren run towards me and make out lights twinkling on Christmas trees," Keith Hayman, a 68-year-old former butcher told BBC.。

"I would be talking to a friend, who might have walked off and I couldn't tell and kept talking to myself, this doesn't happen any more, because I can tell when they have gone ... These little things make all the difference to me."。

However, despite its reported success, the Argus II Bionic Eye has also seen its share of criticism. The MIT Technology Review reported in 2015 that its “artificially created vision is also distorted in certain characteristic ways,” citing the research of Geoffrey Boynton, a professor of psychology at the University of Washington.。

Boynton and fellow Washington psychology researcher Ione Fine looked at computer-simulated images based on the reports of people wearing the retinal implant. Some patients reported seeing streaks or distorted images, as challenges arose dealing with elements such as the retina’s anatomy, computer algorithms used to produce the images and retinal cell diversity, according to the research.。