Seiki Kōgaku (精機光学) was the name of Canon's predecessor until 1947. This page is about a different company of the same name.
Seiki Kogaku Co. (certainly 精機光学, Seiki Kōgaku, meaning "Precision Optics") was a Japanese company, which made two subminiature cameras in the late 1940s or early 1950s: the regular Seiki 16 inspired by the Mamiya 16, and a pistol-shaped evolution.
- McKeown, James M. and Joan C. McKeown's Price Guide to Antique and Classic Cameras, 12th Edition, 2005-2006. USA, Centennial Photo Service, 2004. ISBN 0-931838-40-1 (hardcover). ISBN 0-931838-41-X (softcover).
- Sugiyama, Kōichi (杉山浩一); Naoi, Hiroaki (直井浩明); Bullock, John R. The Collector's Guide to Japanese Cameras. 国産カメラ図鑑 (Kokusan kamera zukan). Tokyo: Asahi Sonorama, 1985. ISBN 4-257-03187-5.