Modern camouflage is more than terrain-colored fabric. Currently, the military needs to be masked in the infrared spectrum. But few people know that there is another way to detect a soldier: using sensors that work in the ultraviolet spectrum.
Compact infrared sensors are quite widespread in the armies of developed countries. However, their manufacture requires sophisticated technologies, and they cost from thousands to tens of thousands of dollars. Therefore, for example, soldiers of the US Army may not be afraid of widespread use of thermal imagers among the Taliban. Nevertheless, American military uniforms are manufactured to provide stealth in the infrared range.
However, there are many commercially available instruments that allow observation in the UV range. You can buy a camcorder online for $ 100 and simply redesign it for real-time shooting in the near ultraviolet spectrum at wavelengths from 330 to 1250 nm. In such a camera, a soldier in camouflage will appear as a bright blue spot that can be easily detected from a distance of at least 100 m.
"Ultraviolet reconnaissance" is most effective in the Arctic, where UV rays are especially bright. Also, the amount of ultraviolet radiation increases at dusk at dawn, on cloudy days, and in such conditions, simple UV video cameras can sometimes be even more useful than thermal imagers.
The capabilities of ultraviolet sensors should be taken into account when camouflaging personnel, machinery and equipment. The near ultraviolet spectrum, especially 320-400 nm, has an amazing ability to display object details even at a great distance. A modified digital SLR camera with a 400mm lens can detect camouflaged soldiers at a distance of a kilometer. Using such UV cameras or video cameras, you can quickly study the mountain valley from a height and call fire on targets that consider themselves well camouflaged. The exact range of such observation devices is unknown for the simple reason that no one has yet seriously engaged in such measurements. However, scientists are currently using UV cameras to measure one part per million sulfur oxide in volcanic plumes from a distance of 16 km.
The US Army recognizes the need for UV camouflage. Soldier training guidelines require measures to be taken to camouflage them from ultraviolet sensors. In addition, the most recent US Army Field Manual in the section on camouflage (FM 20-3) notes that the threat of UV sensors is underestimated by military personnel, as they rarely know about the capabilities of specific sensors or combinations of systems that the enemy is using.
UV cameras are known to pose a significant threat in snowy areas as snow reflects UV rays better than most white paints and man-made objects. Photographic reconnaissance systems with simple UV filters can easily highlight military targets as dark spots on snowy surfaces.
Few people know, but in dense foliage, a UV camera is also a very useful tool. The fact is that green foliage absorbs ultraviolet light, reflecting only 7% of the radiation, while most camouflage patterns reflect much more ultraviolet light. Sand, depending on its silicon content, reflects only about 3% of UV rays, while many tawny and gray camouflage fabrics reflect up to 50% or more. For example, the famous ghillie suit, which is used by American snipers, hides the fighter in visible light so that the enemy can literally step on the sniper's head, but the ghillie is clearly visible in the UV range.
Why are UV cameras not used in summer and in places where there is no snow? The answer is simple: wealthy armies use thermal imagers extensively, and assorted terrorists and insurgents simply do not know about the possibilities of observation in the ultraviolet range.
Be that as it may, the US Army has drawn attention to the potential vulnerability of its soldiers. In particular, demand from the military has spawned simple solutions such as UVR Defense Tech's spray. It is applied to uniforms to reduce UV reflectivity.
