L3-13
Show spherical aberration in a spherical mirror.

Spherical aberration can be shown using a number of rays to show how they focus. The number and spacing of rays can be changed by choice of slit baffle and changing the position of the baffle. A baffle with pairs of rays equidistant from the optical axis of different colors can be used to emphasize the difference between pairs of rays.

Using a rectangular open baffle the caustic can be illustrated, as in the photograph at the right above.

l3-13a