Laser microscope for time-resolved fluorescence spectroscopy

A description is given of a new automated laser fluorescence microscope. The fluorescence is excited by picosecond YAG:Nd laser pulses at a repetition frequency of 5 kHz. The spatial resolution of the microspectrofluorimeter is 1 μm. The temporal resolution of the system, based on counting single photons, is in the subnanosecond range. A report is given of the application of this microfluorimeter in determination of the spectral and temporal characteristics of hematoporphyrin in a single cell.