Microspectrophotometry is the measure of the spectra of microscopic samples using different wavelengths of electromagnetic radiation (e.g. ultraviolet, visible and near infrared, etc.)
A microspectrophotometer can be configured to measure transmittance, absorbance, reflectance, light polarization, fluorescence (or other types of luminescence such as photoluminescence) of sample areas less than a micrometer in diameter through a modified optical microscope.
The main reason to use microspectrophotometry is the ability to measure the optical spectra of samples with a spatial resolution on the micron scale.
Samples that emit electromagnetic radiation via fluorescence, phosphorescence or photoluminescence when exposed to light, can be quantitatively investigated using a variety of excitation and barrier filters.
A variety of observations can be made on samples of interest by using different illumination sources such as halogen, xenon, deuterium and mercury lamps.