Have A Go: Spherical Aberration

Spherical Aberration

This applet demonstrates spherical aberrations in a convex singlet lens. The rays are traced using Snell's law to calculate the refraction at each surface. Note the different focal points for the rays passing nearer to the center versus near the edge. This is known as spherical aberration. The geometrical properties of the lens are adjustable with the sliders. Spherical aberrations tend to increase when rays are bent more at the surfaces of the lens.

Try increasing the radius of curvature of each surface:

• How do the angles of refraction at each surface change?
• How does the separation between the foci change?

Try increasing the refractive index:

• How do the angles of refraction at each surface change?
• How does the separation between the foci change?