Laser

Laser beams in fog that are reflected on a car windshield.

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]

The world's biggest and most energetic laser is the National Ignition Facility (NIF) located at Lawrence Livermore National Laboratory (LLNL) in Livermore California.

## References[edit]

1. ↑ http://lisa.jpl.nasa.gov
2. ↑ https://edition.cnn.com/videos/us/2015/03/05/orig-lockheed-martin-laser-blasts-truck.cnn
3. ↑ https://edition.cnn.com/2014/12/11/tech/innovation/navy-laser-weapon/index.html
4. ↑ http://www.popsci.com/tags/laser-weapons