Direct measurement of the constituents flow field by the spontaneous Raman imaging technique(I)

A spontaneous Raman imaging system has been described that can monitor the concentrations of major species in flow field in real time. We present the results of the species in the air with a doubled Nd:YAG laser and a single intensified CCD array at the exit of an imaging spectrograph. The output laser energy and the position of the measurement point have effect on the precision. The error is calculated to be less than 8%. The measurement precision of O2（a1Δ） concentration will be improved largely when this technique is applied to monitor chemical oxygen-iodine laser singlet oxygen generator performance.