At the beginning of the war, the searchlight units were attached to fortress artillery. Each regiment had 2-3 lighting platoons, each equipped with 1 piece of 90 cm and a smaller 60 or 35 cm lighting device. The number of searchlight platoons and devices multiplied during the Great War, as in the case of many other technical devices and troops. In addition to artillery, searchlights appeared in 1915 at all infantry units.
The devices were very diverse in terms of operation and size. Acetylene and electric light source, various versions of mirror sizes ranging from 25 cm to 150 cm were used. The earliest devices were mounted 35 cm devices of the M97 pattern. The brightness of the early devices was very limited. These parameters were significantly increased by later developments.
By 1917, the equipment of the previously organized separate searchlight formations was standardized. 110, 60 and 35 centimeter electrical devices of the M15 pattern were introduced. The larger-diameter devices were operated by the searchlight squadrons assigned to the divisions, and the smaller devices by the searchlight swarms assigned to the regiments. By 1918, a total of 1,150 different devices were used. I wrote about headlight formations here before.
On the two types of badges designed for the searchlight troops, we can see a larger, 90 cm and a smaller, 35 cm device. It is interesting that the latter device is used by soldiers of cavalry units in both the picture and the Kappenabzeichen. Obviously, this was a lighter, more portable device than the larger headlights with a mechanical lifting mechanism transported on a trolley.
