Our eyes are the organs that allow us to see. They take in light and images and turn them into electrical signals that our brain can understand. When we see an object, we are actually seeing light rays that bounce off objects and into our eyes. Light enters through the pupil, the black spot in the middle of the eye. The pupil is a hole that opens and closes with the help of the iris (the colored part of the eye) to control the amount of light that enters the eye. If the light is too bright, the pupil shrinks to let in less light to protect the eye. If it is dark, the pupil opens to let more light into the eye.
The Six Million Dollar Man was a science fiction and action television series in the 1970s about an astronaut who was given superhuman strength and abilities from bionic implants that got inside of him after having an accident while in space. His left eye was replaced with a "bionic" implant that made his vision far better than the normal human eye.
Today a bionic eye exists in real life--except without the superhuman abilities, of course! Scientists around the world have been working on an artificial eye to help bring back vision to people who have lost their sight from eye diseases or possibly to people who were born blind. Some bionic vision devices (“eyes”) have already been implanted (or put) into patients.
The first bionic (artificial) vision began as a pair of special glasses with a camera in the middle. Information from the camera is sent to an implant that is sewn into the patient’s retina. The retina is the back part of the eye that contains the cells that respond to light. The signals are sent from there to the visual centers of the brain. The problem with this device is that vision was not clear enough for the person to be able to get around, like being able to see the crosswalk lines to cross the street safely.
The bionic implant sees a blurred image made from flashes of light rather than a steady visual perception. The flashes of light give visual information in the form of a basic shape. This basic shape can show how tall or wide an object is and where it is located. But bionic vision does not allow the person to see in color and the bionic implant is very expensive (around $160,000).
Patients who became blind from an eye disease have said they have been given the ability to read large print books and to cross the street on their own. Clinical trials show that the bionic eye is safe and reliable in restoring a sense of sight to those who cannot see. Unfortunately, bionic eyes are not able to bring back vision completely, and they cannot give sight to someone who has never had it.
There are plans to improve the current model of bionic implants to give sharper and clearer vision to people who became blind from eye diseases. Scientists are also testing a brain implant that would not require the patient to have a working eye. Instead of implanting directly into the eye, electrodes are placed in the visual cortex (outer layer) of the brain. A video camera attached to special glasses then sends information to the visual cortex. There is the possibility that newer models may even produce color vision.
As technology continues to advance and change, bionic eyes could possibly correct most forms of vision loss in the future.