Lenses
For materials that have the entrance and exit surfaces non-parallel: the direction of light beam changes
The best results obtained by lenses: piece of glass with spherical surfaces
- those that converge light rays (like concave mirrors)
- those that diverge the light rays (like convex mirrors)
Converging and Diverging lens
Characteristic points and lines:
- focal point (on both sides)
- focal length (equal on both sides)