Fluorescence spectroscopy is a technique that analyses the emitted fluorescence from a sample that has been excited by a beam of light (usually UV). The emitted light – the fluorescence – contains spectral information on the molecular vibrations of the studied sample. Generally, two types of instruments are currently available on market – filter fluorometers and spectrofluorometer. Filter Fluorometers contain an optical filtration system to filter out the excitation beam to allow high-sensitivity detection of the fluorescent light. In contrast, spectrofluorometers usually contain gratings based monochromator systems to isolate the incident excitation beam. Advances in the sensitivity of detection have recently allowed adapting this technique at microscopic levels for the study of biochemical and biophysical properties of cells by combining microscopy and fluorescence spectroscopy into a new technique called microfluorimetry.