Laser source, the use of excited state particles under the action of stimulated radiation light electric light source.Is a kind of coherent light source.Since 1960, the United States of T.H. maiman made since ruby laser, has amounted to hundreds of varieties of all kinds of laser light source, output wavelength range from short-wave ultraviolet to far-infrared.Laser light source according to its working substance (also known as activated substances) divided into solid laser source (crystal and neodymium glass), gas laser source (including atoms, ions, molecules, excimer), liquid laser source (including organic dyes, inorganic liquid, chelate) and semiconductor laser source four types.
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