Vastly improving digital technology makes artificial retinas a possibility in the next few years. Those who get them will have trouble adjusting. The human eye works in ways which digital receptors can't replace. Either the humans or the machines will have to adapt.
The eye takes in information by allowing light in through a lens at the front of the eyeball, and focusing it on the retina at the back of the eyeball. The retina is covered in photo receptors; 127 million of them spread over 1100 square millimeters. Digital cameras now have about 16.6 million photoreceptors over about 1600 square millimeters. Clearly, there's a ways to go, but given the improvement of technology year-to-year, it can't be too long before doctors are able to whip up an eyeball for someone.
Sadly, it's not so simple. Professor Richard Taylor, of the University of Oregons physics department and art department, believes that human and technological visual systems aren't even remotely interchangeable. In the eye, the majority of cones are located centrally. People are most aware of what's in front of them, and are generally not aware of details at the edges of their vision. If a person needs more detailed information about an object, they turn their heads and look directly at it. This is not a habit, or a matter of comfort, but a function of they structure of the eye. The fovea, the part of the eye that analyzes detail, is a pin-sized area just behind the lens. This helps people take in small amounts of visual information. A large flat screen of information, in which every detail pops out equally, may be too much for brains to process.
What's more, the fovea, with its miniscule range, helps soothe humans. Although most people are not aware of it, their eyes are moving constantly. Although people may rest their eyes on a panorama, to take in details they have to look around. This effect if even more pronounced when they look at small spaces, because the fovea has to move more dramatically to take in different sections. Although it may sound annoying, many believe it's soothing. The motion of the eye is not random. It curves around fractals - repeated patterns found in nature. Following these patterns, which are often aesthetically pleasing, is like lingering on beauty, and releases endorphins. Seeing a static picture in which every detail is taken in at once may render people unable to find the same satisfaction.
Making a robotic eye for people may necessitate building in weaknesses and strengths that allow it to behave like a human eyes. Then again, who knows what people may see with an entirely new visual process given to them? Perhaps a new artistic conception of beauty can be found - one that uses more complexity, or a different framing process than current art allows. When implants become available, will cyborg art come with them?
Read more about the study via Physics World
