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A laser weapon

Light Amplification by Stimulated Emission of Radiation (or laser) was discovered on Earth in the early 20th century. Most lasers use a form of crystal or gas in which the electrons have been raised to an excited state. Mirrors are then used to reflect stray photons back and forth through this medium, provoking a cascade reaction that releases a burst of light. The beam emitted from a laser is monochromatic, coherent, and has a very high intensity. High-energy lasers are thus able to focus large amounts of energy onto very small areas, which can result in considerable physical damage.
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