Word Study
anastigmatic
CIDE DICTIONARY
anastigmatic, a. [Pref. an-not + astigmatic.].
Not astigmatic; free of astigmatism; -- pertaining to a lens or lens system, and used especially of a lens system which consists of a converging lens and a diverging lens of equal and opposite astigmatism but different focal lengths, and sensibly free from astigmatism. [Webster 1913 Suppl.]
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