Chapter27[1]

Chapter27[1] - Chapter 27 THE HUMAN EYE 1 The greatest...

Info icon This preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 27 THE HUMAN EYE: 1. The greatest refraction of light occurs at the air (n = 1.00) – CORNEA ( n = 1.38 ) interface. 2. Secondary refraction occurs at the AQUEOUS HUMOR (n = 1.33) – LENS (n = 1.40) interface. 3. The shape of the LENS , and so its focal length is adjusted by the CILIARY MUSCLE. 4. For far away objects, f . The muscle is relaxed, and the lens is flat. Stop studying now and then to focus on far away objects and you can minimize eye strain. 5. For close objects, the muscle tenses to shorten the focal length of the lens. 6. The process of changing the lens shape is called ACCOMODATON. Newborns take about 6 weeks to do this.
Image of page 1

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

View Full Document Right Arrow Icon
The NEAR POINT (N) is the closest an object can be to the eye and still be in focus. The eye produces a real, inverted image on the RETINA. Example: N = 25 cm. Pretend the eye is a single thin lens that is 2.5 cm from the retina. What is the focal length of the eye’s lens when it is focused on a) the near point, and b) infinity?
Image of page 2
We are looking for f. 1 1 o i 1 1 o i 1 1 1 1 a) f 2.3cm d d 25cm 2.5cm 1 1 1 1 b) f 2.5cm d d 2.5cm LENSES IN COMBINATION.
Image of page 3

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

View Full Document Right Arrow Icon
1. Pretend that the 2 nd (right) lens isn’t there and locate the
Image of page 4
Image of page 5
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