Fero 51

The Fero 51 is a binocular night vision device designed during the Cold War for West German (Bundeswehr), Austrian, and Swiss military forces. It was a pioneering piece of equipment developed by a collaboration involving Zeiss, Eltro, AEG-Telefunken and De Oude Delft. Unlike modern "starlight" amplifiers, the Fero 51 is an active Gen 0 system, meaning it requires an external infrared flashlight to illuminate the target for a clear image. It was heavily relied on as a key tool within military intelligence and border surveillance by both German and Swiss forces.

Developed in the 1960s and 1970s, it provided excellent resolution and clarity when used with an IR illuminator, sometimes reported to function even better than earlier Generation 1+ passive systems, with effective ranges of 100–300+ meters. The device's features include a 6x magnification, 6°30' field of view and a 1.5V battery-operated converter. The design included a protective rubber coating and an automatic power cut-off mechanism protecting the NVD from phosphor burns. The Fero 51 represents an important stepping stone between the active infrared systems of World War II and the passive "starlight" scopes (like the AN/PVS-2) developed in the 1960s.