Infrared Forest Fire Alarm

Wang Zhepu; Cheng Cuhua

doi:10.1117/12.957999

17 December 1979 Infrared Forest Fire Alarm

Wang Zhepu, Cheng Cuhua

Proceedings Volume 0197, Modern Utilization of Infrared Technology V; (1979) https://doi.org/10.1117/12.957999
Event: 23rd Annual Technical Symposium, 1979, San Diego, United States

Abstract

An infrared forest fire alarm for surveillance of initial small forest fire is described. It is made up of a reflective opto-mechanical scanning system and a display unit with an audible alarm. The scanning system is controlled by an automatic mechanism which makes the Spiral scanning proceeds continuously from 0 to 12 degrees in'elevation and vice verse. The optics with an IFOV of 1 mr scans 360degrees in azimuth. The design assures that the radiant beam from the target falls stably on the thertoelectridally cooled HgCdTe detector which is situated in the center of the rotating axis. The spectral filter before the detector suppresses all background radiation below 3 um. The display unit is consisted of a CRT 'screen and a loudspeaker. The target can be displayed by two selectable modes: a light spot on the screen to indicate the position of the target or a waveform to show the amplitude of the signal. The audio frequency used is 400hz. The scanning system and the display unit can be mounted together or separately with a distance of 1 km. For example, the former can be located on a hill top and the latter situated at the foot of that hill with a cable linking the two.

Citation Download Citation

Wang Zhepu and Cheng Cuhua "Infrared Forest Fire Alarm", Proc. SPIE 0197, Modern Utilization of Infrared Technology V, (17 December 1979); https://doi.org/10.1117/12.957999

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