The present invention additionally comprises a method and apparatus for
generating and mixing signals for frequency-domain lifetime and spectral
fluorometry. The present invention comprises a plurality of signal
generators that generate a plurality of signals where the signal
generators modulate the amplitude and/or the frequency of the signals.
The present invention uses one of these signals to drive an excitation
signal that the present invention then directs and transmits at a target
mixture, which absorbs the energy from the excitation signal. The
property of fluorescence causes the target mixture to emit an emitted
signal that the present invention detects with a signal detector. The
present invention uses a plurality of mixers to produce a processor
reference signal and a data signal. The present invention then uses a
processor to compare the processor reference signal with the data signal
by analyzing the differences in the phase and the differences in the
amplitude between the two signals. The processor then extracts the
fluorescence lifetime and fluorescence spectrum of the emitted signal
from the phase and amplitude information using a chemometric analysis.