Definition of aplanat in English:

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Pronunciation: /ˈapləˌnat/


A reflecting or refracting surface that is free from spherical aberration.
Example sentences
  • When viewing resolution is less critical, the aplanats offer an economical alternative.
  • We do not know what led him to this highly successful design, but it may have been an assembly of two Grubb-type landscape aplanats about a central stop.
  • All six lenses are fully corrected aplanats, so they can be mixed and matched in a focusing or non-focusing configuration to obtain the desired magnification.



Pronunciation: /ˌapləˈnatik/
Example sentences
  • The results indicates that the aplanatic hologram lenses are feasible for optical disk applications.
  • These locations for which spherical correction has been optimized are called the aplanatic points.
  • We can apply the same reasoning to rods and transformation of cylindrical diverging wavefront using aplanatic points of the rods.


Late 19th century: coined in German from Greek aplanētos 'free from error', from a- 'not' + planan 'wander'.

For editors and proofreaders

Syllabification: ap·la·nat

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