How Does The Human Eye Work?

December 31, 2019


The human eye is very complex, containing several different parts that do different jobs which allow us to see. Identifying the ways these parts work together and understanding how the eye works can be very beneficial in helping you to realize if there is ever an issue with your eye. You’ll be able to explain your symptoms more appropriately to your doctor.

Main Parts Of The Eye

Below are the main parts that make up the eye

  • Cornea: the clear, circular window at the front of the eye
  • Pupil: the opening at the center of the iris
  • Iris: the colored part of the eye
  • Lens: the transparent, double-convex portion of the eye
  • Retina: the membrane at the back of the eye

The Eye’s Process

Below is the eye’s process and how the different parts work together to allow you to see images.

Light reflects off of objects and enter the eye.

When light rays enter the eye, they enter through the cornea which is the clear front of your eye. The cornea bends the light and allows it to pass through the pupil, which is the opening in the center of the iris.

The iris determines how much light enters the eye by enlarging and shrinking.

After the light passes through the iris, light rays then reach the lens. The lens then works like a camera and focuses the light rays properly. After the lens brings the image into sharp focus, it’s sent to the receiving area at the back of the eye called the retina.

The retina is a membrane full of photoreceptors, or rods and cones, that convert the light rays into electrical impulses, which then travel through the optic nerve at the back of the eye, then to the brain. Then the brain perceives the image.

Sometimes, certain parts don’t function correctly and the process doesn’t follow this structure. In those cases, the eye has a refractive error, a disease or a condition, or is damaged in some way.

Certain Eye Conditions

  • Refractive error: When the shape of the cornea is irregular, light does not focus directly onto the retina. This causes the image to be blurry.
    • Myopia:Occurs when light is focused too far forward in the eye
    • Hyperopia:Occurs when light is focused too far back in the eye
  • Cataract:A cloudiness on the lens that blocks light from getting through.
  • Astigmatism:A condition caused by imperfections in the cornea, resulting in light being focused at two different points.

Fortunately, if you’re dealing with any of these issues, there are ways to deal with them. Our physicians are dedicated to providing the best quality in eye care so that our patients achieve the best vision possible.

Our experienced and dedicated staff, doctors and surgeons make sure you’re always comfortable and provide answers to any questions you may have.

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