How we see
There are many different
parts of the eye that help to create
vision.
Light passes through the
cornea, the clear, dome-shaped surface
that covers the front of the eye. The cornea
bends - or refracts - this incoming light.
The
iris, the colored part of the eye,
regulates the size of the pupil, the opening
that controls the amount of light that
enters the eye. Behind the pupil is the
lens, a clear part of the eye that further
focuses light, or an image, onto the
retina.
The Retina
The retina is a thin, delicate,
photosensitive tissue that contains the
special "photoreceptor" cells that convert
light into electrical signals. These
electrical signals are processed further,
and then travel from the retina of the eye
to the brain through the optic nerve, a
bundle of about one million nerve fibers. We
"see" with our brains; our eyes collect
visual information and begin this complex
process.
Some information courtesy of
National Eye Inst.
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