STUDIES TO DETERMINE THE FEASIBILITY OF MEASURING AIRBORNE DEBRIS IN DUST AND HOT GAS ENVIRONMENTS USING AN INFRARED SCANNING CAMERA.

The report describes the theory for the absorption and scattering of electromagnetic energy by a dielectric particle, gas molecules, non-disperse clouds of the same particle material size, clouds having specified distribution of particle sizes, and clouds of particles in air. The analysis is specialized to consider the transmission of images through the fine particles and hot gases generated by the detonation products of a TNT explosion, as detected by visible light and infrared wavelength photography. The theory is further expanded to include discussion of the detection of objects in the explosion products by the emission and reflection of infrared energy from the object. A BOFORS Model T-101 infrared scanning camera with a frame speed of four frames per second was used to obtain infrared pictures of targets in the 1.0- to 5.5-micron wavelength region in laboratory tests, cloud chamber tests, and in 2-pound TNT explosives tests. Target pictures were enhanced by the use of infrared flare illumination, a magnifying mirror, and filtration of unwanted background. Author