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An Achromatic telescope uses an achromatic lens to correct for this. An achromatic lens is a compound lenses made with two types of glass with different dispersion. One element, a concave lens made out of Flint glass, has relatively high dispersion, while the other, a convex element made of Crown glass, has a lower dispersion. The crown lens is ...
Primary lens: The objective of a refracting telescope. Primary mirror: The objective of a reflecting telescope. Corrector plate: A full aperture negative lens placed before a primary mirror designed to correct the optical aberrations of the mirror. Schmidt corrector plate: An aspheric-shaped corrector plate used in the Schmidt telescope.
An achromatic doublet brings red and blue light to the same focus, and is the earliest example of an achromatic lens. In an achromatic lens, two wavelengths are brought into the same focus, here red and blue. An achromatic lens or achromat is a lens that is designed to limit the effects of chromatic and spherical aberration. Achromatic lenses ...
A diagram of imaging with a single thick lens imaging. H 1 and H 2 are principal points where principal planes of the thick lens cross the optical axis. If the object and image spaces are the same medium, then these points are also nodal points. A camera lens forms a real image of a distant object.
The telescope is more a discovery of optical craftsmen than an invention of a scientist. [1] [2] The lens and the properties of refracting and reflecting light had been known since antiquity, and theory on how they worked was developed by ancient Greek philosophers, preserved and expanded on in the medieval Islamic world, and had reached a significantly advanced state by the time of the ...
Telescopes can be classified by optical design or mechanical design/construction. Telescopes can also be classified by where they are placed, such as space telescopes . One major determining factor is type of light, or particle being observed including devices referred to as "telescopes" that do not form an image or use optics.
It was first proposed in 1817 by the mathematician Carl Friedrich Gauss for a refracting telescope design, but was seldom implemented and is better known as the basis for the Double-Gauss lens first proposed in 1888 by Alvan Graham Clark, which is a four-element, four-group compound lens that uses a symmetric pair of Gauss lenses.
Chester Moore Hall (9 December 1703, Leigh, Essex, England – 17 March 1771, Sutton) was a British lawyer and inventor who produced the first achromatic lenses in 1729 or 1733 (accounts differ). He used the achromatic lens to build the first achromatic telescope , a refracting telescope free from chromatic aberration (colour distortion).