Germany became a leader in optical design, technical innovation and manufacturing of optical instruments during the 1940’s, specifically those crafted by Carl Zeiss, whose company continues to manufacture high quality optics to this day.
The 10X80 20° binoculars were used by the German Navy (Kriegsmarine) on the Conning Towers of U-Boats to spot and shoot down aircraft of enemy bombers. The binoculars could be mounted directly on the anti-aircraft guns or used for spotting at great distances.
At the time, the binoculars were the highest quality in existence which allowed the Kriegsmarine to identify markings of planes at great distances, in varying degrees of light. They came equipped with a yellow contrast-enhance filter and a neutral density filter for sunlight or search light glare, which increased visibility when air and sea were hard to distinguish, for low light conditions at night, and when looking close to sun.
As WWII escalated in 1940, Germany wanted to keep the location of the factories that made their optical and precision instruments a secret. To do this, they assigned three letter codes which were engraved onto the instruments, in this case, 10x80 - 20° Kriegsmarine Binoculars, instead of the actual manufacturer.
Kriegsmarine 10x80 - 20° binoculars were manufactured in three main factories: Carl Zeiss (supplier code blc), Optical Precision Work (Warsaw, Poland supplier code eug), and Ducati (Italy, supplier code mlr).
Code blc – Carl Zeiss, Jena, Germany
Founded in 1846, Carl Zeiss Company has grown into the international Zeiss Group. During WWII Carl Zeiss built quality optical lenses which were thought to be second to none.
Code eug – Optische Prazisions, Warschau, Poland
In 1930, Carl Zeiss Works tried to buy out the firm which was a well-respected optic production house.
Code mlr – Società Scientifica Radiobrevetti Ducati (SSRD), Italy
Ducati is the same firm that later manufactured popular motor bikes. They named the Kreigsmarine 10x80 Binoculars “Bimar” which stood for BInocolo, Marino (sea binoculars). Ducati supplied approximately 450 BIMAR to Germany in the 1940’s. They continued to manufacture them after the war and sold about 150 more, according to their records, which were sold in the civilian market.
Components to Note
The quality of these binoculars is demonstrated by its features. Many of these binoculars ended up at the bottom of the sea, but if you are lucky enough to find a pair, they will have many of these features intact, or in some form. Previous owners over the years may have made some modifications. The one thing they should have is the mark (code) of where it was manufactured. Here are other features that made these so coveted.
Best optics available for WWII binoculars
20° planked eye piece which is best for looking at the horizon - 30° extreme range
Open framed range finder and a port for the reticule illuminator
Air drying system that is used during maintenance
Caps for Desiccator that keeps fog away from interior
Large aperture for high resolution. Oversized prisms and large eyepieces (36 mm in diameter)
Adjustable eyepieces for focus using the levers on the eyepieces and the interocular distance adjustment using a side knob
Wrap around black rubber brow rest that moves horizontally to aid in the interpupillary distance. A smaller secondary brow rest fits under the main.
Large rain guards fit around the 80mm object glasses and sea water drainage holes
Color lenses with night and day filter adjustments
Two desiccator cartridges filled with gel to absorb moisture