Heinz Kilfitt was was the designer of the famous Robot cameras. In 1941, he bought a small factory in Munich and started building his own lenses. He became one of the best and most innovative German lens makers of the 1950ís and 1960ís.
Heinz Kilfitt founded an optical company in Leichtenstein in 1947 that was subsequently relocated to Munich. Four families of lenses were produced (KI, AN, WE, and N) but the KI lenses are by far the most common. These have a 39mm thread designed to fit into a Kilfitt Reflex Housing but with a KIVIS adaptor or equivalent, these could be used on a Viso II/IIa/III. The Kilfitt line included the original Zoomar lens, made under contract for Voigtlander.
When he retired in 1968, he sold the factory to Dr. Frank Back, who operated it under the Zoomar name from its headquarters in Long Island, New York. Lenses were produced until 1971.
Iit subsequently restricted itself to military optics only and left the civilian market in 1986. The entire Kilfitt/Zoomar lens line is most impressive. The most highly sought after lenses are the 2.8/90 Makro-Kilar, the 4/300 Pan-Tele-Kilar, and the two Zooomatars, 5.6/500 and 1000 catadioptric lenses
Every Kilfitt lens was tested before leaving the factory. Film was not considered flat enough for accurate tests, so it was shot on glass plates -- two of them. One plate went out with the lens, the other stayed at the factory for future comparisons if the lens was ever returned for repairs. The lenses were bolted to a tripod head mounted in concrete in the basement of the Kilfitt factory. Mr. Kilfitt wanted to turn out quality lenses, and he did. Not only did he make lenses, he also designed cameras. The Robot, the Mecaflex and the Kowa 2 1/4 are all Mr. Kilfitt's designs. Kilfitt's and Zoomars are fine lenses of great precision and optical performance, but today they are hard to find -- at least in the US.
After the war he worked for Heinz Kilfitt as a mechanical designer, and was the main designer of the very advanced Kilfitt SLR with a super fast metal bladed shutter. Unfortunately that camera never was produced, and only a few prototypes were built. I don't think anyone knows what became of those.
The 300 and longer non-mirror lenses are more likely to have coating problems than not, leading to believe the factory coating on large lens surfaces was often not up to the challenge. Well known for optical innovation, Kilfitt specialized in two areas: macro lenses and zooms - his factories invented both. In 1955 Kilfitt made world's first 35mm macro lens, the 40/2.8 Kilar. In 1959 the Kilfitt factory turned out the world's first production 35mm zoom lens, the 36-82/2.8 Zoomar. Not too bad for an independent factory