Pentax (Asahi Optical)

Asahi Optical began in Tokyo in 1919, grinding spectacle lenses. Its 1952 Asahiflex was the first Japanese 35mm single-lens reflex, and a 1954 version added an instant-return mirror, so the viewfinder no longer went dark after each shot.

The 1957 Asahi Pentax added a fixed pentaprism, and its name became the company’s. The 1964 Spotmatic metered through the lens. The company was renamed Pentax in 2002 and bought by Hoya in 2007.