An advantage of the microscope spectrometer is its ability to use microscope apertures to precisely control the area of sample analysis. Flat capillaries can be used for analyzing small liquid samples, up to about 10 micro-liters in volume. Quartz or mirror-based optics can be used for studying samples from the ultraviolet (UV), down to 200 nm, to the near infrared (NIR) up to 2100 nm.  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. Plane polarized light can also be used for studying birefringent samples.