Spectrometers are optical devices, and often are called prism spectrometers because they often

use a prism for light dispersion. As explained in the grating chapter, some devices use a diffraction

grating in place of a prism because the dispersion from a grating can be much greater than that of a

prism. Light dispersion occurs in a prism and in water particles in the atmosphere. Spectrometers

are commonly used to analyse the wavelengths emitted by a light source. These devices are very

useful to firefighters in identifying the fire coming from a burning object. Once they identify the

type of the burning object, they easily can put out the fire with an appropriate fire extinguisher.