For what it is worth, here is some of the Wikipedia entry on Voigtlander:
"Schering sold its share of the company to the
Carl Zeiss Foundation in 1956, and
Zeiss-Ikon and
Voigtländer-Vertriebsgesellschaft integrated in 1965. Due to falling sales, on 4 August 1971
Zeiss-Ikon/Voigtländer-Vertriebsgesellschaft ended producing cameras and closed the Voigtländer factory, which employed at the time 2,037 persons. Subsequently, the company moved to the collective enterprise
Optische Werke Voigtländer (Optical Works Voigtländer), in which
Carl Zeiss AG, the state of
Lower Saxony and the
Braunschweig camera manufacturer
Rollei each participated to one-third; Later Rollei took over all the shares. On the collapse of Rollei in 1982, Plusfoto took over the name, selling it in 1997 to Ringfoto.
Contemporary times[edit]
Since 1999, Voigtländer-branded products have been manufactured and marketed by the Japanese optics and camera company
Cosina, under license from Ringfoto GmbH & Co. ALFO Marketing KG."
All I can find for Voigtlander GmbH is a police investigative supply store in Blumberg, Germany: Voigtländer GmbH Polizei- und Kriminaltechnik