What is "anastigmat"

anastigmat \anastigmat\ n. 1. compound lens or lens system designed to be free of astigmatism and able to form approximately point images.

n. (context photography English) An anastigmatic lens.

n. compound lens or lens system designed to be free of astigmatism and able to form approximately point images

An anastigmat or anastigmatic lens is a photographic lens completely corrected for spherical aberration, coma, and astigmatism. Early lenses often included the word Anastigmat in their name to advertise this new feature (Doppel-Anastigmat, Voigtländer Anastigmat Skopar, etc.). All modern photographic lenses are close to being anastigmatic.

The first Anastigmat was designed by Paul Rudolph for the Carl Zeiss AG in 1890.