Difference between revisions of "Laser"
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The use of lasers is very important in [[science]] and [[medicine]]; they have also become ubiquitous in [[CD-ROM]] and [[DVD]] players and as pointers. <ref>http://lisa.jpl.nasa.gov</ref> They're also used in bar code scanners. | The use of lasers is very important in [[science]] and [[medicine]]; they have also become ubiquitous in [[CD-ROM]] and [[DVD]] players and as pointers. <ref>http://lisa.jpl.nasa.gov</ref> They're also used in bar code scanners. | ||
| − | In recent years, lasers have even become a seemingly effective weapon for certain militaries. They seem effective against a variety of targets, including planes, missiles, and ground vehicles.<ref> | + | In recent years, lasers have even become a seemingly effective weapon for certain militaries. They seem effective against a variety of targets, including planes, missiles, and ground vehicles.<ref>https://edition.cnn.com/videos/us/2015/03/05/orig-lockheed-martin-laser-blasts-truck.cnn</ref><ref>https://edition.cnn.com/2014/12/11/tech/innovation/navy-laser-weapon/index.html</ref><ref>http://www.popsci.com/tags/laser-weapons</ref> |
==References== | ==References== | ||
Revision as of 16:29, April 9, 2019
Laser is a word formed from the acronym "Light Amplification by Stimulated Emission of Radiation."
Light from a laser is both temporally coherent, meaning it is of a single pure color, and spatially coherent, meaning that it can be easily formed into a thin beam or focused to a small spot. The angle at which a laser beam spreads is determined by diffraction; a wide beam will diverge more slowly than a narrow beam. Many cheap laser pointers exhibit excess beam dissipation due to cheap manufacturing, and shoddy construction.
The use of lasers is very important in science and medicine; they have also become ubiquitous in CD-ROM and DVD players and as pointers. [1] They're also used in bar code scanners. In recent years, lasers have even become a seemingly effective weapon for certain militaries. They seem effective against a variety of targets, including planes, missiles, and ground vehicles.[2][3][4]