Editing Green (section)

=== Lasers ===
[[Image:Starfire Optical Range - three lasers into space.jpg|right|thumb|Three green lasers being fired at a single spot in the sky from the [[Starfire Optical Range]]]]

[[Laser]]s emitting in the green part of the spectrum are widely available to the general public in a wide range of output powers. Green laser pointers outputting at 532&nbsp;[[Nanometre|nm]] (563.5&nbsp;[[terahertz radiation|THz]]) are relatively inexpensive compared to other wavelengths of the same power, and are very popular due to their good beam quality and very high apparent brightness. The most common green lasers use diode pumped solid state ([[DPSS]]) technology to create the green light.<ref name=laserglow>
{{cite web
 |title=Green lasers
 |website=Laserglow (Laserglow.com)
 |url=http://www.laserglow.com/page/greenlaserpointer
 |access-date=27 September 2011
}}
</ref>
An infrared [[laser diode]] at 808&nbsp;nm is used to pump a crystal of neodymium-[[Doping (semiconductor)|doped]] yttrium vanadium oxide (Nd:YVO4) or neodymium-doped yttrium aluminium garnet (Nd:YAG) and induces it to emit 281.76 THz (1064&nbsp;nm). This deeper infrared light is then passed through another crystal containing potassium, titanium and phosphorus (KTP), whose non-linear properties generate light at a frequency that is twice that of the incident beam (563.5 THz); in this case corresponding to the wavelength of 532&nbsp;nm ("green").<ref name="Sams Laser FAQ">
{{cite web
 |title=Sam's laser FAQ
 |website=donklipstein.com
 |publisher=Sam Goldwasser
 |url=http://donklipstein.com/laserssl.htm
 |access-date=27 September 2011
}}
</ref>
Other green wavelengths are also available using DPSS technology ranging from 501&nbsp;nm to 543&nbsp;nm.<ref name=laserglow2>
{{cite web
 |title=DPSS lasers
 |website=Laserglow (Laserglow.com)
 |url=http://www.laserglow.com/int-labOEM.htm 
 |access-date=27 September 2011
}}
</ref>
Green wavelengths are also available from [[gas laser]]s, including the [[helium–neon laser]] (543&nbsp;nm), the Argon-[[ion laser]] (514&nbsp;nm) and the Krypton-ion laser (521&nbsp;nm and 531&nbsp;nm), as well as liquid [[dye laser]]s. Green lasers have a wide variety of applications, including pointing, illumination, surgery, [[laser light shows]], [[spectroscopy]], [[interferometry]], [[fluorescence]], [[holography]], [[machine vision]], [[non-lethal weapons]], and [[bird control]].<ref name=laserglow3>{{cite web
 |title=Green lasers for bird control / abatement
 |website=Laserglow (Laserglow.com)
 |url=http://www.laserglow.com/page/golfcoursebirdcontrol
 |access-date=27 September 2011
 |archive-date=August 7, 2020
 |archive-url=https://web.archive.org/web/20200807160555/https://www.laserglow.com/page/golfcoursebirdcontrol
 |url-status=dead
 }}</ref>

As of mid-2011, direct green laser diodes at 510&nbsp;nm and 500&nbsp;nm have become generally available,<ref>
{{cite web
 |title=Review: 510&nbsp;nm direct green diodes / Build Photos (DGH-N1, DGH-N2)
 |date=13 December 2011
 |department=Discuss Laser Pointers
 |website=Laser Pointer Forums (laserpointerforums.com)
 |url=http://laserpointerforums.com/f45/review-510nm-direct-green-diodes-build-photos-dgh-n1-dgh-n2-69678.html
 |access-date=March 17, 2016
}}
</ref>
although the price remains relatively prohibitive for widespread public use. The efficiency of these lasers (peak 3%){{citation needed|date=August 2013}} compared to that of DPSS green lasers (peak 35%){{citation needed|date=August 2013}}<ref>
{{cite journal
 |last=Davarcioglu  |first=Burhan
 |date=December 2010
 |title=An overview of diode pumped solid state (DPSS) lasers
 |journal=International Archive of Applied Sciences and Technology
 |volume=1 |pages=1–12
 |url=https://www.researchgate.net/profile/Al_Timimi_Zahra/post/What_are_the_limtations_of_using_diode_laser_for_pumping_some_lasers/attachment/5d8ca3b93843b0b982663797/AS%3A807347454758914%401569498041146/download/1.pdf
 |via=researchgate.net
}}
</ref>
may also be limiting adoption of the diodes to niche uses.