Basics of Lasers

Laser is an acronym for Light Amplification by Stimulated Emission of Radiation. The world's first laser was demonstrated by Maiman using a ruby crystal (Maiman 1960). It is essentially a coherent, convergent, and monochromatic beam of electromagnetic radiation with wavelength ranging from ultraviolet to infrared. Lasers have now found applications in almost every field of engineering, medicine, electronics, etc., where one or more properties of the laser radiation are important (Ion 2005; Dausinger et al. 2004; Wolbarsht 1991; Steen 1991). In order to realize the applicability and capability of a laser radiation in any application, it is necessary to understand the basic operation mechanism and properties of laser radiation. These aspects of laser radiations along with the important industrial laser types are briefly discussed in this chapter.