The problem of laser-pulse non-ideality in non-linear laser-based diagnostics

Non-ideality of laser pulses is due to uneven spatial, temporal and spectral distributions of laser beams. Unfortunately, such deviations from hypothetical regular laser profiles are crucial for the correct data interpretation of measurements obtained in some diagnostic applications of non-linear spectroscopy. In this Lecture, methods to circumvent wrong interpretation of spectroscopic data will be presented. To that end, the problem will be specified to incoherent non-linearity that is typical for saturated behavior in fluorescence spectroscopy. Traditional solutions will be briefly recalled and new methods will be discussed.