See also Sankyō Kōki, which made the Komura lenses from the 1950s onwards.
Sankyō Kōgaku Kōgyō (三共光学工業) is a Japanese lens maker founded in 1929, which is still in existence today (2009). It was incorporated as Sankyō Kōgaku Kōgyō K.K. (三共光学工業㈱) in 1949, and founded various dependent companies from the 1970s onwards. The company currently manufactures lens elements, prisms and other optical devices. It does not seem that the company produced entire camera lenses.
The name SANKYO KOGAKU appears on the top plate of the Baika 3×4cm camera with focal plane shutter, made c.1937. This camera is identical to the Lausar camera made by Tomioka, but the inscription might indicate a relation with Sankyō Kōgaku Kōgyō.