Refracting telescope
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A refracting telescope is a type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spyglasses and astronomical telescopes
A 200 mm diameter refracting telescope at the Poznań Observatory
Engraved illustration of a 46 m (150 ft) focal length Keplerian astronomical refracting telescope built by Johannes Hevelius.
Alvan Clark polishes the big Yerkes achromatic objective lens, over 1 meter (100 cm) across (1896).
This 12-inch (30 cm) refractor is mounted in a dome on a mount that matches the Earth's rotation.
Binoculars
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Binoculars or field glasses are two refracting telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes when viewing distant objects. Most binoc
Refracting telescope
…later, two and even three element lenses were made. Refracting telescopes use technology that has often been applied to other optical devices, such as binoculars and zoom lenses/telephoto lens/long-focus lens. Refractors were the earliest type of optical telescope. The first record of a refracting telescope…
8×42 roof prism binoculars with rainguard and opened tethered lens caps
WW1 era Galilean type binoculars
Porro prism binoculars, with distinctive eyepiece/objective axis offset
Binoculars diagram showing an Abbe–Koenig roof prism design