Optical Board - Converging Spherical Lens

Purpose

To show focusing of a spherical (cylindrical) convex lens.

Equipment

Optical board with convex cylindrical lens, concave and convex lenses to produce parallel rays.

Images

l6-01

Description

Parallel rays incident on an 18 inch long convex cylindrical lens converge at the focal point of the lens. For a large aperture the spherical aberration is clearly seen, and chromatic aberration can be seen by blocking part of an extreme ray.Number of slits and their spacing can be changed by choice of slit baffle and distance of baffle from source.

References

Alex J. Dragt, Lie Albegraic Theory of Geometrical Optics and Optical Aberrations, Journal of the Optical Society of America 72,372-379.