The use of laser induced fluorescence spectroscopy (LIF) is described
for making measurements in the combustion environment. Some background
in molecular structure, spectroscopic concepts, thermodynamics and co
mbustion chemistry is first presented. This is followed by application
of the rate equations to model and demonstrate the response of atomic
and molecular systems to laser excitation. Next, experimental aspects
are explored, including excitation, optical signal collection, disper
sion and detection, signal conditioning, uncertainty and detectability
, recovering population distributions from spectra, and sources of sys
tematic error. Finally, specific strategies for measuring concentratio
n, temperature, pressure and velocity are discussed. An example of sel
ecting a collisional rate set for modeling purposes is given in an App
endix.