Near-Infrared NIR Compositions

From Fig. 2.29 (top) it is clear that NIR flares based on pure cesium formulations (CSNO3) are superior emitters in the NIR region, whereas cesium/potassium based formulations (CSNO3/KNO3) (Fig. 2.29 bottom) show a NIR color impurity with taihng into the visible red region. 

The radiant intensity (7) is a measure of radiometric power per unit solid angle Q (Q = A/r ), expressed in watts per steradian (W sr ). The value of the solid angle Q is numerically equal to the size of that area divided by the square of the radius of the sphere. For hand-held NIR flares one wants a reasonable bum time (ca. 45 s), a high concealment index X which is defined as the ratio of the radiant intensity in the near IR region (/nir, 700-1000 nm) over the radiant intensity in the visible region (/vis. 400-700 nm) and high radiant intensities in the NIR regions /i(600-900 nm) and 72(695-1050)  

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