Concave Mirrors
A mirror can be curved instead of being flat. If the surface
curves inwards, it is a concave mirror. Parallel light rays coming into a parallel mirror
are all reflected throught the same point in front of the mirror. The point in front of
the mirror where the reflected rays meet is known as the focal point.
Light rays follow the same paths in the opposite direction if they are coming from the
focal point rather from space. All of them will be reflected back as one concentrated
light ray.
They may be used in reflecting telescopes to gather light from space. Moreover, serving as
a placement behind car headlights to focus light beam is another benefit. One last use is
the usage of searchlights and spotlights.
