 Schlieren photography may be used to provide an early warning of an imminent threat or impending attack, and if sufficiently advanced, may be used in the elimination of stealth targets.This discipline includes both measuring the performance of lasers of interest, and using lasers as part of MASINT sensors.With respect to foreign lasers, focus of the collection is on laser detection, laser threat warning, and precise measurement of the frequencies, power levels, wave propagation, determination of power source, and other technical and operating characteristics associated with laser systems strategic and tactical weapons, range finders, and illuminators.