Cosina Co., Ltd. (株式会社コシナ, Kabushiki-gaisha Koshina) is a manufacturer of high-end optical glass, optical precision equipment, cameras, video and electronic related equipment, based in Nakano, Nagano Prefecture, Japan.

At about this time, plans were started to produce a new high-quality rangefinder 35 mm film camera, complete with wide and ultrawide lenses for the Leica screw mount, and also a standard 35 mm film camera for the amateur film photography sector — similar to a rangefinder camera, but without a rangefinder or viewfinder — for mounting these lenses.

It quickly followed with a wider range of Voigtländer cameras (starting with the Bessa-R, with viewfinder and rangefinder, and the Bessa-T, with rangefinder, but no viewfinder), and a set of lenses, including the Heliar 12 mm f/5.6 lens, which on its introduction was the widest rectilinear lens ever marketed for still photography.

The Cosina Voigtländer cameras and lenses have been of great personal interest to Kobayashi Hirofumi (小林博文) (b.

1953), the President of Cosina since the death in 1988 of his father Kobayashi Bunjirō (小林文治郎), the founder.

Cosina manufactures manual focus SLR lenses for Carl Zeiss AG with: Leica (ZM),[5] Nikon (ZF), Pentax (ZK), Canon EOS (ZE), and M42 (ZS) lens screw mounts.