How
The Eyes Work
Have you ever heard the adage that we
don’t see with our eyes, “we see with our brain”? Well, it’s true. The eyes are
responsible for transmitting images to the brain, by focusing on an object and
understanding what the object is. It is the shape and size of your eye that
determines whether our eyes are able to focus on an object, or if corrective
ophthalmic lenses are necessary. When your eye focuses on an object, an image
is formed. The brain then processes the object, projecting a virtual image.
Optical scientists rely on our knowledge of eyesight, the brain and how it
processes images to design the best possible lenses to correct an individual’s
blurry vision.
The Human Vision System is a complex
system consisting of two sets of lenses (the cornea and crystalline lens), two
sensing devices (retina), and the brain. The Cornea is in the front of the eye
and is responsible for focusing on an image. The Crystalline Lens is found in
the anterior chamber of the eye, which not only focuses on an image, but
adjusts your eyes to see objects far away, or within a short distance as well
as close up. Consider when you wake up from a nap and try to focus on an image.
Your eyes may have to blink once or twice to actually see a clear image.
The cornea and crystalline lens of the
eye both carry a curved shaped, making our eyes appear round. When the cornea
and crystalline lens of the eye are of normal size and shape, we see images
clearly. If, however, a person’s cornea is too curved or not curved enough,
they have a Refractive Error. Simply stated, a refractive error means that
there is an error in getting the eye to focus clearly on an image. Ophthalmic
Lenses are needed to focus on an object and perceive it clearly. Refractive
Errors include Myopia, Hyperopia and Astigmia.
If you are Myopic, Hyperopic or
Astigmatic, you will need an ophthalmic lens to assist your eyes to see
clearly. If your eyes also need help focusing on images close up, you have a
condition known as Presbyopia. This means that your crystalline lens, due to
the natural aging process, can no longer focus and adjust your focus as it used
to. In this case, additional magnification is needed to focus up close. This
additional magnification can be obtained through reading glasses, bifocals, or
progressive addition lenses.
Our eyes are considered by many as the
most precious of senses. We only get one set, and it is vital that we care for
and protect them. No matter what refractive error one may have, clear,
uncompromised vision is possible with a great lens. Improvements in science and
technology allow lens engineers to recreate vision through lens designs. When
it comes to your vision, if you need corrective lenses, insist quality so your
eyes will be able to perform to your highest expectations.
Come back next week to learn more about the different ophthalmic lens types.
Trust your eyes to the local experts at Prairie EyeCare Center, East side of the Square, Broken Bow.

Posted on
Mon, February 15, 2010
by Melinda Kennel