CREATING THE JOY OF SIGHT FOR THE BLIND PPT

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INTRODUCTION:
Artificial-vision researchers take inspiration from another device, the cochlear implant, which has successfully restored hearing to thousands of deaf people. But the human vision system is far more complicated than that of hearing. The eye is one of the most amazing organs in the body. Before we understand how artificial vision is created, it's important to know about the important role that the retina plays in how we see. Here is a simple explanation of what happens when we look at an object:
• Scattered light from the object enters through the cornea.
• The light is projected onto the retina.
• The retina sends messages to the brain through the optic nerve.
• The brain interprets what the object is.


The retina is complex in itself. This thin membrane at the back of the eye is a vital part of our ability to see



HOW TO CREATE ARTIFICIAL VISION?
The current path that scientists are taking to create artificial vision received a jolt in 1988, when Dr. Mark Humayun demonstrated that a blind person could be made to see light by stimulating the nerve ganglia behind the retina with an electrical current. This test proved that the nerves behind the retina still functioned even when the retina had degenerated.


ADVANCEMENTS IN CREATING ARTIFICIAL VISION:
Ceramic optical detectors based on the photo-ferroelectrics effect are being developed for direct implantation into the eyes of patients with retinal dystrophies. In retinal dystrophies, where the optic nerve and retinal ganglia are intact (such as Retinitis Pigmentosa) direct retinal implant of an optical detector to stimulate retinal ganglia could allow patients to regain some sight.