ABSTRACT
Laser radiation is not a natural phenomenon, but is produced by a specialised device known as a laser (an acronym for light amplication by stimulated radiation). Lasers generate electromagnetic radiation with optical radiation wavelengths ranging from 100 nm to 1 mm. Lasers use stimulated emission of radiation, and their radiation differs signicantly in its physical properties from the classical optical radiation emitted by conventional sources such as ultraviolet, infrared radiation, or light sources used for lighting purposes. Many techniques are used to produce laser beams, so lasers can vary greatly.
