Active camouflage
Active camouflage or adaptive camouflage is camouflage that adapts, often rapidly, to the surroundings of an object such as an animal or military vehicle. In theory, active camouflage could provide perfect concealment from visual detection.[1]
Active camouflage is used in several groups of animals, including
Military counter-illumination camouflage was first investigated during the
In animals
Active camouflage is used in several groups of animals including cephalopod molluscs,[2] fish,[3] and reptiles.[4] There are two mechanisms of active camouflage in animals: color change[4] and counter-illumination.[2]
Counter-illumination
Counter-illumination is camouflage using the production of light to blend in against a lit background. In the sea, light comes down from the surface, so when marine animals are seen from below, they appear darker than the background. Some species of cephalopod, such as the
Color change
Color change permits camouflage against different backgrounds. Many cephalopods including octopuses, cuttlefish, and squids, and some terrestrial amphibians and reptiles including chameleons and anoles can rapidly change color and pattern, though the major reasons for this include signaling, not only camouflage.[7][4] Cephalopod active camouflage has stimulated military research in the United States.[8]
Active camouflage by color change is used by many bottom-living flatfish such as plaice, sole, and flounder that actively copy the patterns and colors of the seafloor below them.[3] For example, the tropical flounder Bothus ocellatus can match its pattern to "a wide range of background textures"[9] in 2–8 seconds.[9] Similarly, the coral reef fish, the seaweed blenny can match its coloration to its surroundings.[10]
In research
Active camouflage provides concealment by making an object not merely generally similar to its surroundings, but effectively invisible with "illusory transparency" through accurate mimicry, and by changing the appearance of the object as changes occur in its background.[1]
Early research
Military interest in active camouflage has its origins in Second World War studies of
Possible technologies
Active camouflage may now develop using
In 2003 researchers at the University of Tokyo under Susumu Tachi created a prototype active camouflage system using material impregnated with retroreflective glass beads. The viewer stands in front of the cloth viewing the cloth through a transparent glass plate. A video camera behind the cloth captures the background behind the cloth. A video projector projects this image on to the glass plate which is angled so that it acts as a partial mirror reflecting a small portion of the projected light onto the cloth. The retroreflectors in the cloth reflect the image back towards the glass plate which being only weakly reflecting allows most of the retroreflected light to pass through to be seen by the viewer. The system only works when seen from a certain angle.[13]
Phased-array optics would implement active camouflage, not by producing a two-dimensional image of background scenery on an object, but by computational holography to produce a three-dimensional hologram of background scenery on an object to be concealed. Unlike a two-dimensional image, the holographic image would appear to be the actual scenery behind the object independent of viewer distance or view angle.[14]
Military prototypes
In 2010, the Israeli company Eltics created an early prototype of a system of tiles for infrared camouflage of vehicles. In 2011,
In fiction
Active camouflage technology, both visual and otherwise, is a commonly used plot device in
See also
- Cloaking device
- Cloak of invisibility
- Penetration aid
- Snow camouflage – color change with the seasons
- Stealth technology
References
- ^ a b c McKee, Kent W.; Tack, David W. (2007). "Active Camouflage For Infantry Headwear Applications" (PDF). HumanSystems: iii. Archived from the original on October 7, 2012.
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(help) - ^ a b c "Midwater Squid, Abralia veranyi". Midwater Squid, Abralia veranyi (with photograph). Smithsonian National Museum of Natural History. Retrieved 28 November 2011.
- ^ .
- ^ a b c Wallin, Margareta (2002). Naturens palett | Hur djur och människor får färg [Nature's Palette | How animals, including humans, produce colors] (PDF) (in Swedish). Vol. 1. Bioscience-explained.org. pp. 1–12. Archived from the original (PDF) on 24 June 2020. Retrieved 9 January 2017.
- PMID 1251214.
- PMID 21141672.
- Dazzled and Deceived: Mimicry and Camouflage. Yale, 2009.
- ISBN 978-1-486-30393-9.
Not surprisingly, this aspect of cephalopod biology has become the subject of US military research with millions of dollars currently being poured into studies on cephalopod camouflage.
- ^ S2CID 4304531.
- ^ Bester, Cathleen. "Seaweed blenny". Ichthyology. Florida Museum of Natural History. Archived from the original on 20 September 2015. Retrieved 6 January 2015.
- ^ Bush, Vannevar; Conant, James; Harrison, George (1946). "Camouflage of Sea-Search Aircraft" (PDF). Visibility Studies and Some Applications in the Field of Camouflage. Office of Scientific Research and Development, National Defence Research Committee. pp. 225–240. Archived from the original (PDF) on October 23, 2013. Retrieved 12 February 2013.
- ^ "Light and Dark: The Invisible Man". Time magazine. 18 November 2003. Archived from the original on 18 November 2003. Retrieved 8 January 2022.
- ISBN 978-0-262-03237-7. Retrieved 18 February 2007.
- ^ a b "Adaptiv-A Cloak of Invisibility". BAE Systems. 2011. Retrieved 13 June 2012.
- ^ Schechter, Erik (1 July 2013). "Whatever Happened to Counter-Infrared Camouflage?". Popular Mechanics. Retrieved 19 February 2017.
- ^ "BBC News Technology". Tanks test infrared invisibility cloak. BBC. 5 September 2011. Retrieved 27 March 2012.
- OCLC 950954032. Retrieved 30 May 2021.
- ^ Robley, Les Paul (December 1987). "Predator: Special Visual Effects". Cinefantastique.
- ISBN 978-1-4654-1159-4.
- ISBN 978-0-7821-4236-5.
- ISBN 978-0744012323.
- Mac OS X). Square Enix.
- ^ a b "Crysis 3: Adaptive Warfare". Crysis.com. Crytek. Archived from the original on 13 August 2016. Retrieved 28 July 2016.
CLOAK ENGAGED: Vanish in broad daylight with active camouflage.
- ^ "Technology in the James Bond Universe". Today's Engineer (January). 2006. Retrieved 14 December 2021.
External links
- "Multi-perspective background simulation cloaking process and apparatus", United States Patent & Trademark Office
- "Scientist show off 'invisible coat'", The Sydney Morning Herald, 30 March 2003
- Phased Array Optics
- "Thermal and Visual Camouflage System Patent No 6,338,292", United States Patent & Trademark Office