11-12-2012, 02:44 PM
BIONIC EYE
bioniceye.ppt (Size: 463 KB / Downloads: 45)
What Is BIONIC EYE?
This is a device that is placed on the back of the eye that will restore sight.
This works at the back of the eyeball as a light transmitter to the brain.
The wire connecting to the nerve going to the brain so that it can read the signal is thinner than a human hair.
Who Is This For?
This is for people who suffer from degenerative blindness that is to the point where they are almost completely blind.
This will also work with patients that are partially blind from optic nerve damage
Working of the System
CCD camera input – External light intensity
CCD output amplitude-modulates laser source
This hits photodiode array of implant
This in turn powers stimulator chip (SC)
SC drives current to electrodes facing retina
This excites the ganglionic cells > axons > optic nerve > visual cortex in occipital lobe of brain
Brain helps in perceiving an image
Artificial Retina Prosthesis using ASR (Artificial Silicon Retina)
Human Eye is similar to a camera
Macula provides the highest
resolution of the image which
we see.
Macula is comprised of multiple
layers of cells which process
the initial “analog” light energy
entering the eye into “digital”
electrochemical impulses.
Human eye has nearly
10^8 photoreceptors.
Fundamental idea behind ASR
ASR is a solid state biocompatible chip which contains an array of photo receptors ,and is implanted to replace the functionality of the defective photoreceptors .
Current generated by the device in response to light stimulation will alter the membrane potential of the overlying neurons and thereby activate the visual system.
Artificial vision created by the controlled electric stimulation of the retina has color.