January 8 Lecture - January 8 2009 Anatomy of the Eyeball...

Info icon This preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
January 8, 2009 Anatomy of the Eyeball - On the back of the eye ball at the retinal layer is a depressed area known as the fovea centralis . o The region immediately surrounding the fovea centralis is the macula lutea - Medial to the fovea centralis , is the optic disc or blind spot where there are no rods or cones o This is the area where the optic nerve exits from the eyeball o Not consciously aware of this in most cases Pg. 584 As you bring the page closer to the eye ball, the eye has to converge to focus on the edge, which shifts the image horizontally across the eye Convergence : the medial movement of the eyeball Viewing and Image - A vertical image will be upside down on the eye ball - A horizontal image will be viewed as if in a mirror - The brain centres in the cerebral cortex will rearrange the image to its appropriate orientation via association - The light rays must move through the lens of the eye and be refracted onto the area of the retina
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
- Three ___ in focusing light rays on the fovea centralis o Refraction: the bending of light rays so that they strike the intended area of retina Accomplished by a number of structures Cornea (as light passes through it will be bent by a certain degree or magnitude) o The cornea is more dense than air so it will bend the light rays according to a certain index o Refractive index is the relative speed at which the light moves through the cornea when compared to its speed in air o R.I > 1 Anterior and posterior region to the iris is filled with a fluid substance known as the aqueous humor which has a refractive index as well The rays will then strike the lens which will further bend the light The posterior cavity of the eye (behind the lens and in front of the retina) has a substance known as vitreous humor , a thick gelatinous consistency, after the light passes through this the light will strike
Image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern