Topic outline

  • Cornea / Tear Film


    As light passes into the eye, it needs to be consolidated and focused so that it lands in an organized pattern on the retina. Most people think of the lens as the main refracting and focusing element of the eye, but this is incorrect. The Cornea is the most important refractive element of the eye and abnormalities in the shape of the corneal surface can lead to many different types of vision problems.

    In this module we'll look at the anatomical structure of the cornea. Next we'll consider how light is refracted and focused onto the retina, so the brain is able to make sense of images coming into the eye. We also need to study different types of corneal pathology as anything that alters the cornea can have an impact on vision.

    We'll also take a few minutes during this module to talk about the tear film. This liquid layer helps nourish and protect the cornea. It has numerous components each made be special secretory glands throughout the eye. Problems with the tear film can lead to dry eye which is both uncomfortable and ultimately harmful to vision.

    Without the cornea and the tear film we would have a very difficult time trying to bring our vision into focus.

    Let's consider how this essential refractive element plays a role in vision.

    Issue Date: 08/01/2020