Authors E.N. Semashkin, T.V. Artyushkina, A.V. Bolotnikov T.V. Garbuzova
Month, Year 10, 2015 @en
Index UDC 623.4.021
Abstract The objective of this article is determination of the TV and thermal imaging devices day-and-night capability under main climatic types: cool (Dickson), moderate (Moscow), warm humid (Batumi), and hot arid climate (Ashkhabad). For this purpose on the basis of the empirical laws of temperature and relative air humidity distribution there was developed a method of simulation of the weather visibility distance distribution in diverse climatic zones, where upper and bottom margins of the weather visibility distance distribution values are the functions of humidity deficit. The simulation validity was approved through experimental researches of the objects visibility from a high-rise laboratory located in the territory of JSC KBP, Tula. The major algorithm is supplemented with models of haze, fog, precipitations. Optical and infrared signals attenuation due to haze was estimated on the basis of the Filippov model, which stipulates that hazes are distributed to several types depending on a temperature of air and season. Fogs model is based on the law of the weather visibility distance distribution in fogs in the course of year; the model of precipitations is based on the law of the various- intensity precipitations duration distribution in the course of year. Estimation of the infrared signals attenuation due to atmospheric gases (oxygen and water vapor) was performed with the use of the Passaman–Larmora tables that present the infrared radiation spectral transmittance factor dependence on the wave length and width of precipitated water sheet. The observing equipment operation range was estimated on the theory of linear filtration, where the under-observation object contrasts attenuated in the atmosphere are compared against contrast resolved by an optical device. Estimations of the operation range were performed for such objects as a men, car, and tank. Estimation of the day-and-night capability was performed for the TV camera and thermal imagers of 3–5 µm and 8–12 µm wavelength. The simulation has shown that at distances of 5 km the thermal imager is twice as good as the TV camera in cool climate. As for moderate and warm climate their factors are similar. In Ashkhabad the factors are actually equal. When the distance is extended to 10 km the factors of the day-and-night capability of the TV camera in a cool climate surpass the factors of the day-and-night capability the thermal imagers by ten times; as for a moderate climate – they are twice as good.

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Keywords Machine vision systems; thermal imager; TV-camera; operation range; all-weather capability.
References 1. Shipunov A.G., Semashkin E.N. Dal'nost' deystviya, vsesutochnost' i vsepogodnost' televizionnykh i teplovizionnykh priborov nablyudeniya [Operation range, day-and-night and all-weather capability of the TV and thermal imaging observation devices]. Moscow: Mashinostroenie, 2011, 218 p.
2. Filippov V.L., Mirumyants S.O. Aerozol'noe oslablenie IK-radiatsii v «oknakh prozrachnosti» atmosfery [Aerosol attenuation of the infrared radiation in atmospheric windows], Izvestiya AN SSSR. Fizika atmosfery i okeana [Izvestiya of Aof Scs USSR. Atmosphere and ocean physics], 1971, Vol. 8. No. 7, pp. 818-819.
3. Barteneva O.D., Dovgyallo E.N., Polyakova E.A. Eksperimental'nye issledovaniya
opticheskikh svoystv prizemnogo sloya atmosfery [Experimental recearches of optical features of near-surface atmosphere], Trudy GGO [Works GGO]. Leningrad: Gidrometeoizdat, 1967, Issue 220, 244 p.
4. Asano S. Light scattering properties of spheroidal particles, 1979.
5. Cai Q., Liou K.-N. Theory of time-dependent multiple back-scattering from clouds, J. Atm. Sci., 1981, Vol. 38, No. 7, pp. 1452-1466.
6. Cameson A.L.H., Quaife R.D. The yearly distribution of rainfall intensities, Meteoral. Mag., 1965, Vol. 94, No. 115. pp. 4.
7. Davis J.M., Cox S.K., McKee T.B. Vertical and horizontal distributions of solar absorption in finite clouds, J. Atm. Sci., 1979, Vol. 36, No. 10, pp. 1976-1984.
8. Grassl H. Bestimmung der Grossenverteilung von Wolkenelementen aus spektralen Transmissionsmessungen, Beitr. Phys. Atm., 1970, Vol. 43, No. 4, pp. 255-284.
9. Hensen J. E., Cheyney H. Theoretical spectra scattering of ice clouds in the near infrared, J. Geoph. Research, 1969, Vol. 74, No. T-13, pp. 3337-3346.
10. Kerker M. The scattering of light and other electromagnetic radiation. New-York, London Acad, Press, 1969, 645 p.
11. Mie G. A contribution to the optics of turbid media, especially colloidal metallic suspensions, Annal. Phys., 1908, Vol. 25, No.4, pp. 377-445.
12. Pawlina A. Some features of ground rain pattern measured by radar in North Italy, Radio Sci., 1984, Vol. 19, No. 3, pp. 855-861.
13. Piass G.N., Kattawar G.N. Radiative transfer in water and and ise clouds in the visible and infrared region, J. Appl. Optics., 1971, Vol. 10, No. 4, pp. 738-748.
14. Rusk A.N., Williams D., Querry M.R. Optical constants of water in the infrared, J. Opt. soc. Amer., 1971, Vol. 61, No. 7, pp. 895-903.
15. Sassen K. Infrared (10,6 ) scattering and extinction in laboratory water and ise clouds, Appl. Opt., 1987, Vol. 20, No. 2, pp. 185-193.
16. Sassen K., Liou K.-N. scattering of polarized laser light by water droplet, mixed-phase and ice crystal clouds. Part 1: Angular scattering patterns, J. Atm. Sci., Vol. 36, No. 5, pp. 838-851.
17. Schaaf J.W., Williams D. Optical constants of ice in the infrared, J. Opt. Soc. Amer., 1973, Vol. 63, No. 6, pp. 720-732.
18. Siedentopf H., Reger E. Met. Zeit. 1944. No. 61, pp. 114.
19. Warren S.G. Optical constants of ice from ultraviolet to the microwave, Appl. Opt.,1984, Vol. 18, No. 8, pp. 1206-1225.
20. Wickramasinghe N.C. Light scattering functions for small particles with applications in astronomy. London. Adam Hilger, 1973, 506 p.

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