We're involved in the development of a prosthesis system to restore sight to patients with degenerative retinal diseases. This is a collaboration with Professor D Palanker (Stanford University) on the microfabrication of the Stanford Retinal Prosthesis device.
The prosthesis converts pulsed infra-red light into electrical current that activates inner retinal neurons in degenerated tissue. The retinal (output) ganglion cells then respond with burst of action potentials sent up the optic nerve.
For more information read our paper on "Photovoltaic retinal prosthesis with high pixel density". The Palanker Lab website also has extra information on this topic.