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Laser Ranging
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The word ''laser'' originated as an acronym for light amplification by stimulated emission of radiation. The first laser was built in 1960 by Theodore Maiman at Hughes Research Laboratories, based on theoretical work by Charles H. Townes and Arthur Leonard Schawlow and the optical amplifier patented by Gordon Gould. A laser differs from other sources of light in that it emits light that is ''coherent''. Spatial coherence allows a laser to be focused to a tight spot, enabling uses such as optical communication, laser cutting, and lithography. It also allows a laser beam to stay narrow over great distances (collimation), used in laser pointers, lidar, and free-space optical communication. Lasers can also have high temporal coherence, which permits them to emit light with a very narrow frequency spectrum. Temporal coherence can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guiding The Milky Way (potw2222a)
Guiding may refer to: *Guide, a person who leads travelers or tourists through unknown or unfamiliar locations *Girl Guiding and Girl Scouting, a Scouting movement *Girlguiding, the United Kingdom's largest girl-only youth organisation *Guiding County, a county in Guizhou Province, China See also * Guidance (other) * Guiting (other), Guiting {{Disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
