
1) Corrected 
Found on 
https://www.crosswordclues.com/clue/aplanatic

a lens free of spherical aberration
Found on 
http://phrontistery.info/a.html

• (a.) Having two or more parts of different curvatures, so combined as to remove spherical aberration; -- said of a lens.
Found on 
http://thinkexist.com/dictionary/meaning/aplanatic/

<microscopy> Corrected for spherical aberration and coma. ... (05 Aug 1998) ... 
Found on 
http://www.encyclo.co.uk/local/20973

(ap″lә-nat´ik) correcting or not affected by spherical aberration.
Found on 
http://www.encyclo.co.uk/local/21001
 Ap`la·nat'ic  adjective
Ap`la·nat'ic  adjective [ Greek 
 'a priv. + ... disposed to wander, wandering, ... to wander.] 
 (Opt.) Having two or more parts of different curvatures, so combined as to remove spherical aberration; -- said of a lens.  
 Aplanatic focus of a lens 
 (Opt.) , 
 the point or f...
Found on http://www.encyclo.co.uk/webster/A/102
 Type: Term Pronunciation: ap-la-nat′ik Definitions: 1. Pertaining to aplanatism, or to an aplanatic lens.
Type: Term Pronunciation: ap-la-nat′ik Definitions: 1. Pertaining to aplanatism, or to an aplanatic lens.
Found on http://www.medilexicon.com/medicaldictionary.php?t=5497
 In optics, aplanatic is a term specifically applied to reflectors, lenses, and combinations of them, capable of transmitting light without spherical aberration. An aplanatic lens is a lens constructed of different media to correct the effects of the unequal refrangibility of the different rays.
In optics, aplanatic is a term specifically applied to reflectors, lenses, and combinations of them, capable of transmitting light without spherical aberration. An aplanatic lens is a lens constructed of different media to correct the effects of the unequal refrangibility of the different rays.
Found on http://www.probertencyclopaedia.com/browse/GA.HTM
 [adj] - (optics) free from or corrected for spherical aberration
[adj] - (optics) free from or corrected for spherical aberration
Found on http://www.webdictionary.co.uk/definition.php?query=aplanatic
 adjective free from or corrected for spherical aberration; `an aplanatic mirror`
 adjective free from or corrected for spherical aberration; `an aplanatic mirror`
Found on https://www.encyclo.co.uk/local/20974
 free from spherical aberration and coma.
free from spherical aberration and coma.
Found on https://www.infoplease.com/dictionary/aplanatic
  No exact match found.