Nanosecond laser fluorometry using a dye laser

A new technique is described for quantitative investigations of the kinetics of spontaneous and stimulated emission from dyes using a tunable dye laser and an analog computer. The proposed method can be used to study the evolution of all the main emission characteristics in the nanosecond range (“instantaneous” emission and excitation spectra, afterglow duration at various recording wavelengths, and polarization of the luminescence). Results are presented of an investigation of the fluorescence kinetics of a solution of 4-amino-N-methylphthalimide in n-propanol, which typically exhibits spectral and temporal relaxation of radiation caused by intermolecular interactions.