Dr Karl Leiss Optische und Mechanische Instrumente

This optical and mechanical instrument making firm in Steglitz and Berlin was founded by Dr. Carl Leiss. Leiss had worked for Rudolf Fuess and in 1893 became head of the optical department at the Rudolf Fuess company. In March 1921, Leiss went out on his own but remained close geographically and intellectually to the Fuess workshop. Both companies made similar goniometers, spectrometers, and other crystallographic and mineralogical and optical instruments.

The company's name was sometimes "Dr. Carl Leiss" and other times "Dr Karl Leiss Optische und Mechanische Instrumente."

After Carl Leiss's death in 1940, his son-in-law, Karl Koletzko, took charge of the company. The firm was dissolved in 1985.