Infrared signature

Infrared signature, as used by defense scientists and the military, is the appearance of objects to infrared sensors.[1] An infrared signature depends on many factors, including the shape and size of the object,[2] temperature,[3] and emissivity, reflection of external sources (earthshine, sunshine, skyshine) from the object's surface,[4] the background against which it is viewed[5] and the waveband of the detecting sensor. As such there is no all-encompassing definition of infrared signature nor any trivial means of measuring it. For example, the infrared signature of a truck viewed against a field will vary significantly with changing weather, time of day and engine loading.

Two fairly successful examples of defining the infrared signature of an object are the apparent temperature difference at the sensor and the contrast radiant intensity (CRI) definitions.

  1. ^ The Handbook Of The SAS And Elite Forces. How The Professionals Fight And Win. Edited by Jon E. Lewis. p.330-Tactics And Techniques, Personal Skills And Techniques. Robinson Publishing Ltd 1997. ISBN 1-85487-675-9
  2. ^ Mahulikar, S.P., Potnuru, S.K., & Kolhe, P.S.: (2007) "Analytical estimation of solid angle subtended by complex well-resolved surfaces for infrared detection studies", Applied Optics, v. 46(22), pp. 4991-4998.
  3. ^ Mahulikar, S.P., Sane, S.K., Gaitonde, U.N., & Marathe A.G.: (2001) "Numerical studies of infrared signature levels of complete aircraft", Aeronautical Journal, v. 105(1046), pp. 185-192.
  4. ^ Mahulikar, S.P., Potnuru, S.K., & Rao, G.A.: (2009) Study of sunshine, skyshine, and earthshine for aircraft infrared detection, Journal of Optics A: Pure & Applied Optics, v. 11(4), no. 045703.
  5. ^ Rao, G.A., & Mahulikar, S.P.: (2005) "Effect of atmospheric transmission and radiance on aircraft infrared signatures", AIAA Journal of Aircraft, v. 42(4), pp. 1046-1054.