Eye Dork - Eye Have the Answer

The retina is an incredibly complex structure.  This entry will be about the larger structures involved in processing an image. To learn how an image is focused on the retina, check out anterior eye anatomy. If you want to learn about the individual cells of the retina, check out phototransduction (conversion of a light ray into a chemical message for the brain). For information on the utilization and regeneration of vitamin A in the retina, check out the biochemistry of the visual process. The goal of glasses, contact lenses or refractive surgery is to get images focused on the fovea of the macula. The macula is the general pigmented area surrounding and supporting the fovea. The fovea is the specific structure that processes all of the detailed (letters, print) visual information we see. The fovea is a small structure, seen on examination only as a small pinpoint of light. In this small space, the fovea packs in over 10...

Light rays from an image are focused onto the retina by glasses or contacts and the anterior structures of the eye. Light rays are converted from a physical wave into a chemical and electrical message to be interpreted by the brain. This process is called phototransduction. In the sensory retina, there five main cell types and nine layers involved in this process. The sensory retina is an optically clear structure. For phototransduction to begin, an image must pass through the anterior blood supply and every layer of the sensory retina until the image finally reaches the photoreceptor layer. The photoreceptor layer is composed of rods and cones. There are roughly 120 million rods in the adult retina. These cells allow us to see the difference between light and dark. Rods are utilized for night vision and low lighting conditions. There are 6 to 7 million cones in the adult eye. Cones are only utilized for day or brighter conditions. These cells are specialize for color detection. ...