aplanat

plural aplanats

1. engineeringA lens that has been corrected for spherical aberration and coma in order to produce a rectilinear image.

   2009, Gérard René Lemaitre, Astronomical Optics and Elasticity Theory, Springer, Astronomy and Astrophysics Library, Corrected 3rd printing, page 11, […] which is totally false since he established the algebraic conditions for thin-lens achromatic aplanats;

   2 more examples

   For comparison, an aplanat of a focus catalogued at 16 inches, actually found by experiment to have a focus of 16 11-16 inches, was used.

   1894, W. K. Burton, “The Zeiss Anastigmatic Lenses”, in Julius F. Sachse, editor, American Journal of Photography, Volume XV, page 4

   Some infra-red detectors are sold already embedded in a plastic aplanat.

   2014, J. F. James, An Introduction to Practical Laboratory Optics, Cambridge University Press, page 171