Planar LIF is a laser based measurement technique for non intrusive studies of combustions and flows. The ultraviolet light of a pulsed laser system is formed to a vertical sheet (stripe) and focussed into the combustion or flow e.g. into the near development field of a burning spray. A limited section of the laser sheet within the test region defines the measurement area. Laser induced fluorescence images were obtained by collecting the fluorescence at 90 degree from the laser light sheet by an intensified CCD camera. The spatial resolution is given by the optical resolution of the whole camera system (UV grade photo lens, image intensifier and CCD-chip) as well as by the thickness of the light sheet. The temporal resolution of a single puls measurement is given by the width of the laserpuls which is typically 5-8ns. For the purpose of data collection and data post processing the images were saved as two dimensional data arrays.
The distribution of fuel droplets at the exit of a spray nozzle can be characterized by PLIF and Mie-scattering measurements. In order to prove single molecular species by PLIF the excitation and the detection wavelength will be selected in regard to the individual spectroscopic properties of the species. Instantaneous (single puls) and mean value distributions of measurement results can be evaluated.