Healthy Eyes

Frequently Asked Questions

1. How do our eyes work?

There are many different parts of the eye that help create vision.

  • Cornea. Light passes through the cornea, the clear, dome-shaped surface that covers the front of the eye. The cornea bends or refracts the light coming into the eye.
  • Iris. The iris is the colored part of the eye. It controls the amount of light that enters the eye through an opening called the pupil.
  • Pupil. The pupil is the opening in the iris. The iris adjusts the size of the pupil and controls the amount of light that can enter the eye.
  • Lens. The lens is a clear part of the eye that focuses light coming into the eye. The lens is behind the pupil and fine tunes the image that reflects onto the retina.
  • Retina. The retina is a thin, delicate, light-sensitive tissue that lines the inside of the eye. It converts light into electrical signals and sends them to the optic nerve.
  • Optic nerve. The optic nerve is a bundle of about one million nerve fibers that carries electrical signals from the eyes to the brain. The brain interprets these signals, allowing us to see.
  • Macula. The macula is the most sensitive part of the retina. It provides the sharp, central vision we use for activities such as reading and watching television.