Retinal prostheses are rapidly advancing into real world implementations. Experiments in this field of science began maybe not more than a decade ago, but basic devices which could help blind people see at least objects of relatively large size apparently can be manufactured already today.
Such devices are using a principle of conversion of a real world image into corresponding Braille code which is sent to bio-image sensor implanted over person’s retina. Obviously, such device has drawbacks, since the integrated image recognition currently can deal only with very limited number of pixels. Despite this, seeing at least large objects like stairs or doorways could help blind people deal with quite difficult situations.
And how about using some text recognition? Developers say it is quite possible:
Prostheses such as the Argus II, manufactured by Second Sight in Sylmar, California, convert video from a camera mounted on a pair of glasses into electronic signals “displayed” on a 10-by-6 grid of electrodes implanted over a person’s retina. This gives users a pixellated view of the world, allowing them to distinguish light and dark regions and even detect features such as doorways.
But deciphering letters and words with the prosthesis is slow because of its low resolution. To make this more practical, Thomas Lauritzen of Second Sight and colleagues have come up with a modified version of the Argus II that presents the user with Braille. Since Braille represents letters and numbers as dots in a 3-by-2 grid, it can be displayed using the electrode array of existing Argus implants.
The modified implant was tried out on a Braille-reading volunteer who already uses the Argus II. Tested on single letters and words of up to four letters, transmitted in Braille to the retinal implant, he correctly identified the letters 89 per cent of the time and words 60 to 80 per cent of the time. Longer words should actually be easier to read, Lauritzen predicts, because getting an individual letter wrong creates less confusion than when the word is short.
Read more at: Newscientist.com