A Celor lens (also known as a symmetric dialyte) is a highly corrected
lens
A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'' ...
of the Dialyt type, designed for process photography, involving reproduction at or near 1:1 scale.
It was developed in 1898 by Emil von Hoegh, an optical designer working for the German company
Goerz
Rudolf Goerz (sometimes spelled Rudolph) (born 1879 and died 1935) was a German botanist.
He was particularly interested in spermatophytes.