We have learned that when light is reflected from a flat mirror, the
angle between the reflected beam and the mirror is the same as the
angle of the incident beam and the mirror.
This rule also applies to light reflecting from a curved mirror.
The difference is that light encounters the
curved mirror at different angles at different places, and thus is reflected
at different angles. It helps to imagine
that a curved mirror is made up of many tiny flat mirrors all joined together
in a curved shape, and then envision each tiny flat mirror reflecting light
in the predictable flat mirror way. Curved
mirrors can give a distorted or magnified reflection. They also are
able to bring parallel beams of light together at a point.
