A laser is a device that emits light (electromagnetic radiation)
through a process called stimulated emission. The term "laser" is an
acronym for Light Amplification by Stimulated Emission of
Radiation.Laser light is usually spatially coherent, which means that
the light either is emitted in a narrow, low-divergence beam, or can
be converted into one with the help of optical components such as
lenses. Typically, lasers are thought of as emitting light with a
narrow wavelength spectrum ("monochromatic" light).



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