Aplanatic
Aplanatic ({not transcribed}) , adjective
[Greek 'a priv. + {not transcribed} disposed to wander, wandering, {not transcribed} to wander.]
(Optics) Having two or more parts of different curvatures, so combined as to remove spherical aberration; -- said of a lens.
Collocations (1)
Aplanatic focus (Optics) , the point or focus from which rays diverging pass the lens without spherical aberration. In certain forms of lenses there are two such foci; and it is by taking advantage of this fact that the best aplanatic object glasses of microscopes are constructed.