Refracting telescope

A refracting or refractor telescope is a type of optical telescope which refracts light at each end using lenses. This refraction causes parallel light rays to converge at a focal point; while those which were not parallel converge upon a focal plane. This can enable a user to view a distant object as if it were brighter, clearer, and/or larger. These are similar to microscopes. The monocular is a type of refractor. A typical refractor has two lenses, an objective lens and an eyepiece lens. The objective lens has two pieces of glass (with different densities), "crown" and "flint glass". Each side of each piece is ground and polished, and then the two pieces are glued together. The curvatures are designed to limit the effects of chromatic and spherical aberration.

See also

• List of largest optical refracting telescopes, from which it is clear that their heyday was in the 19th century
• Maksutov telescope