Wilhelm Stein

Wilhelm "Willi" Stein (1906-1976) was the principal designer of the M-series. He began his career in engineering as an apprentice with the Iron & Steel Works of Buderus in his home town of Wetzlar. In 1936, he moved to Ernst Leitz GmbH. Barnack, who initiated and supervised the development of the original Leica, died in January of that year. This left a gap among the remaining engineers. Ludwig Leitz recognized Stein's talents and gave him an opportunity to make contributions with the company's design group.

Some credit Stein with the improvement of the focal plane shutter which Barnack invented in 1924. He was not drafted into the German Army but instead was sent to secret military development installations. After the second World War, Stein was made the head of Leica's design department.

(from LHSA's VIEWFINDER Vol. 27, no. 1 - courtesy of Paul Taylor

"Von der Konstruktionsseite für die Leica M3 sind zu nennen: Dr. Ludwig Leitz, LTG.gesammt, Willi Stein, Ltg. Konstruktion und Adolf Groß, Ltg. Formgestaltung sowie Prof. Scheuernstuhl als Bildhauer und sein Meisterschüler Heinrich Janke aus Hannover, der spätere Leiter dieser Abteilung. Später bestand das Team aus Hans-Kurt Uellenberg, H. Janke, Ernst Rühl und Bernd Nickel (von links, siehe Abb.!). Hier 3 Entwürfe für die Leica M3 aus den 50èr und 60èr Jahren. 1953,1956,1957 und 1961. Heute nennt man das Design oder CAD bei Leica. Eine leider früher und auch heute viel zu gering geachtete Species für neue Produkte und ihren Erfolg. Damals hats aber geklappt Grüße Hendrik" hös

Source - [1] #1

E. Leitz Photographic Patents by Wilhelm "Willi" Stein

• 1936 FEB 12 - DEVICE FOR LOADING FILM CASETTES
• 1936 AUG 08 - CAMERA SHUTTER MECHANISM with Ludwig Leitz
• 1950 FEB 09 - CURTAIN SHUTTER CAMERA WITH FLASH SYNCHRONIZING DEVICE with Friedrich Gath
• 1951 JAN 17 - COMBINED EXPOSURE METER AND CAMERA
• 1951 AUG 28 - TIMING MECHANISM FOR CAMERA FOCAL PLANE SHUTTER with Hugo Wehrenfennig
• 1952 JUL 23 - FLASHLIGHT (sic.) ATTACHMENT FOR PHOTOGRAPHIC CAMERAS
• 1954 MAY 06 - CAMERA (M3 see above Figures 1, 2, 3, 4)
• 1960 JUL 11 - COMBINED VIEW AND RANGE FINDER FOR CAMERAS with Ernst Leitz II
• 1962 AUG 24 - RANGE FINDER AND VIEW FINDER FOR PHOTOGRAPHIC CAMERAS with Ernst Leitz II