Scientists have used retinal implants to help blind people read braille. The Argus II device, used in 50 patients, helped one blind patient see projected patterns and letters for the first time by sending images directly to the retina of the eye.
The device uses a small camera mounted on a pair of glasses. A processor translates signals from the camera into electrical signals that in turn transmit to an implant in the retinal cells of the eye.
Researcher Thomas Lauritzen, lead author of the paper explained in a press release, “In this clinical test with a single blind patient, we bypassed the camera that is the usual input for the implant and directly stimulated the retina.
Instead of feeling the braille on the tips of his fingers, the patient could see the patterns we projected and then read individual letters in less than a second with up to 89% accuracy."
For the study, researchers stimulated processed patterns directly to the retina. The patient was able to easily recognize braille. He was also able to recognize single letters and words that contained up to 4 letters.
The scientitsts say the Argus II device has primarily helped people with Retinitis Pigmentosa by restoring limited reading ability when used with the camera.
The hope is that the device could be adapted to provide a faster way to help blind people read text, with the addition of letter recognition software. The device has the ability to process images before signals are sent to the retinal implant.
For the study, the patient was shown letters for a half a second. Accuracy for reading words containing up to 4 letters was 80%.
The study was conducted by researchers at Second Sight whose company developed the Argus II. The finding is published November 22, 2012 in the journal Frontiers in Neuroprosthetics.