The device is comprised of an inch-long video camera mounted on a pair of sunglasses. The camera sends signals down a cable to a handheld control unit about the size of a cell phone, which converts the image into a low resolution black, white and gray picture. That picture is then recreated as a square grid of 400 electrodes, approximately the size of a postage stamp, on the lollipop-shaped stick. Each electrode sends pulses based upon the amount of light detected, with strongest pulses for white, and no signal for black.
Those who could see before they went blind describe the sensations as similar to vision -- although the resolution is not the same, they say.
The idea started with Paul Bach-y Rita, a neuroscientist at University of Wisconsin-Madison. Bach-y-Rita was convinced that the brain, not the eye, is what enables humans to see and can rewire nerve impulses from anywhere, not just the eye, to generate vision.
After 10 hours wearing the device, people have been able to find and walk down a hallway and avoid obstacles, said Aimee Arnoldussen, a neuroscientist who is leading the research. With the device, people also have distinguished a men's room sign from a women's room sign and found doorways, she said.
You don't put the device on and magically see and it isn't a substitute for a cane or a guide dog.
Related technologies: The U.S. Navy is developing a system that will allow divers to find their way through murky waters by interpreting infrared through their tongues.
NASA is creating sensors to enable astronauts to feel objects on the outside of their space suits.
The Institute for Human and Machine Cognition is working toward making vests that will alert pilots to other planes or incoming missiles by sending pulses.