Your Eyes and Vision

Your Eyes and Vision

Our ability to "see" starts when light reflects off an object at which we are looking and enters the eye. As it enters the eye, the light is unfocused. The first step in seeing is to focus the light rays onto the retina, which is the light sensitive layer found inside the eye. Once the light is focused, it stimulates cells to send millions of electrochemical impulses along the optic nerve to the brain. The portion of the brain at the back of the head interprets the impulses, enabling us to see the object.

What is 20/20 Vision?

20/20 describes normal visual clarity or sharpness measured at a distance of 20 feet from an object. If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at that distance. If you have 20/100 vision, it means that you must be as close as 20 feet to see what a person with normal vision can see at 100 feet.

Children's Vision

About 80 percent of all babies are born farsighted -- able to see objects clearly at a distance but less clearly close up. Some five percent are born nearsighted, or unable to see objects at a distance clearly.

Approximately 15 percent are born with nothing wrong with the refractive parts of the eye -- the cornea and crystalline lens which bend light and focus it properly on the retina. Farsightedness usually decreases as a child ages, typically normalizing to a negligible value by the age of 7-8.

Reading and Vision

Eye care experts generally agree: Watching television will not harm your eyes or vision if the TV room is lit properly and if you follow a few viewing tips. In fact, there is usually less strain involved in TV viewing than in doing close work such as sewing or reading. But TV watching for long stretches of time can leave your eyes fatigued.

TV and Vision

Reading requires the integration of eight different vision skills. Only one is checked by the typical school eye chart test. Quick eye examinations may cover only one or two. Since a comprehensive eye examination will cover the eight vision skills, it is a must for anyone having trouble reading. The eight skills include:

  • Visual acuity
  • Visual fixation
  • Accommodation
  • Binocular fusion
  • Stereopsis
  • Convergence
  • Field of vision
  • Perception