A dye laser is a laser that uses an organic dye as a lasing medium, usually as a liquid solution. Compared to gases and most solid-state lasing media, a dye can usually be used for a much wider range of wavelengths. The wide bandwidth make them particularly suitable for tunable lasers and pulsed lasers. Moreover, the dye can be replaced by an other type in order to generate different wavelengths with the same laser, although this usually requires replacing other optical components in the laser as well.

Construction

Since organic dyes tend to degrade under the influence of light, the dye solution is normally circulated from a large reservoir. The dye solution can be flowing through a cuvette, i.e., a glass container, or be as a dye jet, i.e., as a sheet-like stream in open air from a specially-shaped nozzle. With a dye jet, one avoids reflection losses from the glass surfaces and contamination of the walls of the cuvette. These advantages come at the cost of a more-complicated alignment.