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  2. Meniscus corrector - Wikipedia

    en.wikipedia.org/wiki/Meniscus_corrector

    The idea of using the spherical aberration of a meniscus lens to correct the opposite aberration in a spherical objective dates back as far as W. F. Hamilton’s 1814 Hamiltonian telescope, in Colonel A. Mangin's 1876 Mangin mirror, and also appears in Ludwig Schupmann’s Schupmann medial telescope near the end of the 19th century.

  3. Spherical aberration - Wikipedia

    en.wikipedia.org/wiki/Spherical_aberration

    A spherical lens has an aplanatic point (i.e., no spherical aberration) only at a lateral distance from the optical axis that equals the radius of the spherical surface divided by the index of refraction of the lens material. Spherical aberration makes the focus of telescopes and other instruments less than ideal. This is an important effect ...

  4. Distortion (optics) - Wikipedia

    en.wikipedia.org/wiki/Distortion_(optics)

    In geometric optics, distortion is a deviation from rectilinear projection; a projection in which straight lines in a scene remain straight in an image.It is a form of optical aberration that may be distinguished from other aberrations such as spherical aberration, coma, chromatic aberration, field curvature, and astigmatism in a sense that these impact the image sharpness without changing an ...

  5. Ritchey–Chrétien telescope - Wikipedia

    en.wikipedia.org/wiki/Ritchey–Chrétien_telescope

    If the mirror is spherical, it will suffer primarily from spherical aberration. If the mirror is made parabolic, to correct the spherical aberration, then it still suffers from coma and astigmatism, since there are no additional design parameters one can vary to eliminate them. With two non-spherical mirrors, such as the Ritchey–Chrétien ...

  6. Corrective Optics Space Telescope Axial Replacement

    en.wikipedia.org/wiki/Corrective_Optics_Space...

    It was created to correct the spherical aberration of the Hubble Space Telescope ' s primary mirror, which incorrectly focused light upon the Faint Object Camera (FOC), Faint Object Spectrograph (FOS), and Goddard High Resolution Spectrograph (GHRS) instruments. [1]

  7. Coma (optics) - Wikipedia

    en.wikipedia.org/wiki/Coma_(optics)

    Coma of a single lens. Each cone of light focuses on different planes along the optical axis. In optics (especially telescopes), the coma (/ ˈ k oʊ m ə /), or comatic aberration, in an optical system refers to aberration inherent to certain optical designs or due to imperfection in the lens or other components that results in off-axis point sources such as stars appearing distorted ...

  8. Three-mirror anastigmat - Wikipedia

    en.wikipedia.org/wiki/Three-mirror_anastigmat

    A three-mirror anastigmat is an anastigmat telescope built with three curved mirrors, enabling it to minimize all three main optical aberrationsspherical aberration, coma, and astigmatism. This is primarily used to enable wide fields of view, much larger than possible with telescopes with just one or two curved surfaces.

  9. Sextupole magnet - Wikipedia

    en.wikipedia.org/wiki/Sextupole_magnet

    They are used in particle accelerators [1] for the control of chromatic aberrations and for damping the head—tail transverse plasma instability. Two sets of sextupole magnets are used in transmission electron microscopes to correct for spherical aberration.