Curved Mirrors

Not all mirrors are flat. There are also curved or spherical mirrors. These mirrors reflect light in special ways.

Let's imagine a ball. Concave mirrors are the ones whose reflecting surface is the inside part of the ball. Convex mirrors are the ones whose reflecting surface is the outside part of the ball.

Now, let's imagine the center of the ball. This is called the center of curvature (C). The line that passes through the center of curvature and the mirror is the principal axis and the midpoint between the center of curvature and the mirror on the principal axis is called the principal focus (F).



In a concave mirror, the reflected ray will pass through the principal focus if the incident ray is parallel to the principal axis. In a convex mirror, the reflected ray will seem to come from the principal focus if the incident ray is parallel to the principal axis.

The image formed by a convex mirror is also virtual, upright, smaller than the object and is always located behind the mirror. While the type of image formed by a concave mirror depends on the location of the object in front of the concave mirror.

Concave mirrors are converging mirrors while convex mirrors are diverging mirrors.