Several types of “bionic eyes” are beginning to restore sight to the blind:

Keck School of Medicine of the University of Southern California researchers have developed spectacles with miniature video cameras that transmit signals to a 4-mm-by-5-mm retinal implant with 16 electrodes that stimulate remaining healthy retinal cells.

University of New South Wales researchers are developing an implant with 100 electrodes to give patients the ability to differentiate between night and day, detect obstacles and provide some rudimentary reading skills.

Dr. Alan Chow of Optobionics hopes to develop a silicon retina with 4,000 to 5,000 microscopic solar cells that function in place of the eye’s natural sensors.

VisionCare Ophthalmic Technologies is developing an Implantable Miniature Telescope that replaces the eye’s lens. It projects images over the undamaged area of the retina and provides central, “straight-ahead” vision while the other eye handles peripheral vision.