The first artificial retinal implant has been approved in the United States, which reproduces some of the functions of the retina, helping restore vision to people blinded by a rare genetic disorder, according to US news agencies.

The device, made by Second Sight Medical Products Inc, a private California-based company, is designed to replace the function of photosensitive cells in the retina destroyed by retinitis pigmentosa, an inherited degenerative disease that affects about 100,000 people across the country.

In a healthy eye, the retina that lines the back of the inner eye works a bit like a video camera, converting images that come through the lens of the eye into electrical signals that are transmitted through the optic nerve to the brain.

To help this mechanism, scientists created the Argus II device, consisting of special glasses equipped with a video camera and a video processing unit, which sends signals to a wireless receiver implanted in the eye.

Although it cannot fully restore vision, the implant helps with everyday activities, such as placing objects in space and distinguishing between large letters and shapes.

“Patients who currently use the implant have an undeniable improvement in their quality of life,” said Mark Humayun of Keck University, School of Medicine, Southern California, who helped design the device.

Argus II was approved for use in Europe in 2011 and was implanted in 30 patients in clinical trials that began in 2007. In October, the U.S. Food and Drug Administration unanimously approved the device.