What Is a Laser?
Lasers are devices for amplifying (strengthening) light into a powerful beam—a beam that can be focused very sharply, to generate heat or extreme light intensity.
“Laser” is a word made up of the first letters of the words “light amplification (by) stimulated emission (of) radiation.”
The first laser was built in 1960 by Theodore H. Maiman at Hughes Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow.
A laser differs from other sources of light in that it emits light coherently. Spatial coherence allows a laser to be focused to a tight spot, enabling applications such as laser cutting and lithography.
A laser generates and amplifies light waves of a pure color into a narrow beam of light so powerful that it can burn holes in strips of steel in seconds
Lasers are used for accurately measuring distances, in communications and navigation, and for a wide variety of other important jobs. Lasers are used in optical disk drives, laser printers, and barcode scanners; and laser lighting displays in entertainment.