This invention discloses an Excitation Emission Matrix (EEM) fluorescence spectrometer
system that uses an LED array to cause excitation emission matrix fluorescence
that is imaged onto a spectrograph for sample identification and analysis. By using
the LED array, the spectrograph requires only high spectroscopic resolution of
about 1 to 5 nm in the fluorescence emission range and low excitation light resolution
of about 14 to 73 nm in the excitation range. While individual LED optical excitation
spectra may contain wavelength regions that overlap, as long as the various LEDs
have different excitation wavelengths and intensities, spectral overlap does not
preclude data analysis. The invention provides an EEM spectroscopy system that
is not a high resolution such as a laser or lamp based excitation system, but instead
uses a lower resolution, lower power LED system. The invention also provides results
that are comparable to existing systems with lower component cost and lower power
requirements while also optically stable, small, and easy to use.