University of St Andrews
School of Physics and Astronomy

4.  Geometrical Optics I

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Associated tutorial questions (St Andrews only)

• The thin lens equation derived  => 1/u + 1/v = 1/f ,  or in Cartesian sign convention  1 / l' - 1 / l = 1 / f '
• Linear magnification
• Examples of imaging with one lens - a converging lens as a projector, the magnifying glass
• Use this interactive demo to see how a lens works in the above roles.  From Lightlink
• Angular magnification

Note:  It is important that you understand and can reproduce the derivation of the thin lens equation.  However, we will use this equation so many times, that I strongly recommend that you memorise the equation itself, and the sign convention used.   The same is true of the expression for linear magnification, m = -v/u.

Similar material to that presented in the lectures is available at:-

• Halliday, Resnick, & Walker - Chapters on:-  Images
• University of Rochester - Reflection and Refraction at spherical surfaces

Associated tutorial questions (St Andrews only)
Return to Waves and Optics Home Page

Created by, and copyright of, Bruce Sinclair, University of St Andrews; last modified 18/09/01