A small sampling of the many materials that Phytophotonics have measured with laboratory fluorescence spectrophotometers over the years:
Emeralg EEMemerald
Brazilian Emerald:
Fluorescence Excitation-Emission Spectra of Chromium-Containing Gems: An explanation for the effectiveness of the crossed filter method, Hoover, D.B., F.G.A., and Theisen, A.F., May 1993, The Australian Gemmologist. pp 182-187.
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green leaf Yel-Grn leafRed-Yel leaf Shown here are a series of Sweetgum leaf fluorescence measurements for progressive stages of senescence and chlorophyll loss or conversion. While these are grossly different and visually obvious, this spectral method, and the compatible 2-D spectra obtained from the PolyChromatic, provide a way to sense the subtler transitional changes.
Oil 1Oil 2 Oil 3Oil 4Oil 5 Another use of laboratory fluorescence collected and displayed as Excitation- Emission-Matrix (EEM) plots is shown here. Oils from different sources are seen to differ spectrally. Even though they are very similar, such as the first three on the left. Two oils from Alabama are seen to be very different, while the Chunchula oil is seen to be very similar to the generic 45 API gravity crude.

The latest Excitation-Emission-Matrix (EEM) data are collected with a Fluorolog-3® Research Spectrofluorometer (FL-3). This instrument Includes:
o a 450 W ozone free Xenon source and power supply,
o a double Czerny-Turner excitation monochromator with a 1200 g/mm grating blazed at 330 nm,
o a double Czerny-Turner emission monochromator with a 1200 g/mm gratings blazed at 500 nm,
o a multi-alkali Photomultiplier Tube (PMT) emission detector (R928P) with photon counting
   electronics and an output range from 190 nm to 860 nm,

o computer controlled, continuously adjustable entrance and exit slits,
o a T-format sampling module with reflective optics and photodiode reference detector,
o a secondary single monochromator with 600 g/mm grating blazed at 1000 nm,
o an extended infrared capability with liquid nitrogen cooled InGaAs solid state detector with an
   output range from 1
ìm to 1.5 ìm at 77K (-196 ºC), and
a fiber optic sample chamber platform with a 2 m, bifurcated, randomized, fiber optic bundle.

The FL-3 is autocalibrating, upon initialization, based on a stored calibration file. However, the accuracy of this file is checked regularly. Unencumbered and non destructive fluorescence measurements of samples that do not fit standard accessories, loose granular materials, powders, or even liquids require horizontal placement. This configuration is accomplished through the use of a large external sample chamber and a bifurcated fiber optic cable.The chamber system was originally developed for the repetitive measurement of live plants undergoing long term stress treatments.