Abstract: A monochromator utilizing a single light source productive of a uniformly intense, single beam, single wavelength coaxial beam output or alternatively, a single beam selected dual wavelength coaxial beam output.

Abstract: A frequency domain spectrofluorometer employing extrinsically modulated DC light sources or intrinsically modulated laser pulse trains, containing multiple, harmonically related, phase-locked frequencies for exciting a fluorescent sample. High frequency light emissions of the excited sample are simultaneously cross-correlated with multiple, harmonically related, phase-locked R-F frequencies to produce workable low frequency electrical detector signals having the same phase and modulation characteristics as the multiple frequency sample light emissions. The detector signals are digitized in a computer and transformed from time to frequency domain by complex fast fourier transforms to extract the phase and modulation data for all frequencies of the sample light emissions. This data is displayed simultaneously on the visual presentation screen of the computer.