The first Leica lenses were developed by Max Berek (1886–1949). The mathematician and mineralogist joined Leitz straight after his graduation in 1912, one year after Oskar Barnack.
The first models of the Leica I A (introduced in 1925) were equipped with a four-lens Anastigmat 50 mm f/3.5, quickly followed by the five-lens Elmax 50 mm f/3.5.
Still in the same year, Berek redesigned the Elmar 50 mm f/3.5 as a four-lens optic which was easier to construct. In his publication Principles of Practical Optics (1930), Berek describes the Elmar as a modified version of the Cooke Triplet, a classic lens construction from the late 19th century.
The Elmar 50 mm f/3.5 went on to become the classic Leica standard lens, and was produced in over 30 versions over the course of 35 years.