Further Physics - Observing the Universe - Lenses and Telescopes

Further Physics - Observing the Universe - Lenses and Telescopes

Convex Lenses

In a convex lens, also called a converging lens, rays of light are bent inwards as they pass through the lens. If the rays of light entering the lens are parallel, the rays will be brought to focus at a focal point.

A more powerful lens has a more curved surface and a shorter focal length than a weaker lens. The power of a lens is measured in dioptres and can be calculated using the following formula:

Power (dioptre) = 1/Focal Length

Concave Lenses

In a convex lens, also called a diverging lens, rays of light are bent…