Editing Laser pointer (section)

==Hazards and risks==

===Incorrect power rating===
{{Main|Laser safety|Lasers and aviation safety}}
National Institute of Standards and Technology tests<ref>{{cite journal|url=https://www.nist.gov/pml/div686/pointer-032013.cfm |title=NIST Tests Underscore Potential Hazards of Green Laser Pointers |journal=NIST |date=20 March 2013 |publisher=Nist.gov |access-date=22 August 2014}}</ref> conducted on laser pointers labeled as Class IIIa or 3R in 2013 showed that about half of them emitted power at twice the Class limit, making their correct designation Class IIIb – more hazardous than Class IIIa.  
The highest measured power output was 66.5 milliwatts; more than 10 times the limit.  Green laser light is generated from an infrared laser beam, which should be confined
within the laser housing; however, more than 75% of the devices tested were found to emit infrared light in excess of the limit.

===Malicious use===
{{Main|Laser safety|Lasers and aviation safety}}
Laser pointers, with their very long range, are often maliciously shone at people to distract or annoy them, or for fun. This is considered particularly hazardous in the case of aircraft pilots, who may be dazzled or distracted at critical times.

According to an MSNBC report there were over 2,836 incidents logged in the US by the FAA in 2010.<ref>{{cite web|url=http://www.msnbc.msn.com/id/41156165/ns/travel-news/ |archive-url=https://web.archive.org/web/20110121223113/http://www.msnbc.msn.com/id/41156165/ns/travel-news/ |url-status=dead |archive-date=21 January 2011 |title=FAA: Laser incidents soar, threaten planes - Travel - News |publisher=MSNBC |date=20 January 2011 |access-date=8 November 2016}}</ref> Illumination by handheld green lasers is particularly serious, as the wavelength (532&nbsp;nm) is near peak sensitivity of the dark-adapted eye and may appear to be 35 times brighter than a red laser of identical power output.<ref name="faagl">{{cite web| last =Nakagawara| first =Van B., DO| url =http://www.faa.gov/pilots/safety/pilotsafetybrochures/media/laser_hazards_web.pdf| title =Laser Hazards in Navigable Airspace| publisher =FAA| access-date =15 December 2011| archive-url =https://web.archive.org/web/20111216083826/http://www.faa.gov/pilots/safety/pilotsafetybrochures/media/laser_hazards_web.pdf| archive-date =16 December 2011| url-status =dead| df =dmy-all}}</ref>

Irresponsible use of laser pointers is often frowned upon by members of the laser projector community who fear that their misuse may result in legislation affecting lasers designed to be placed within projectors and used within the entertainment industry. Others involved in activities where dazzling or distraction are dangerous are also a concern.

Another distressing and potentially dangerous misuse of laser pointers is to use them when the dot may reasonably be mistaken for that of a laser gun sight. Armed [[police]] have drawn their weapons in such circumstances.<ref name=princeton/>

===Eye injury===
The output of laser pointers available to the general public is limited (and varies by country) in order to prevent accidental damage to the [[retina]] of [[human eye]]s. The U.K. [[Health Protection Agency]] recommended that "laser pointers generally available to the public should be restricted to less than 1 milliwatt as no injuries [like the one reported below to have caused retinal damage] have been reported at this power".<ref name=damage1>{{cite news|url=http://news.bbc.co.uk/1/hi/health/10266498.stm |title=Laser pointers 'pose danger to eyes' |work=BBC News |date=9 June 2010}}</ref><ref name=damage2>[http://www.bmj.com/content/340/bmj.c2982.full Maculopathy from handheld green diode laser pointer], Kimia Ziahosseini, et a., BMJ 2010;340:c2982</ref> In the U.S., regulatory authorities allow lasers up to 5&nbsp;mW.

Studies have found that even low-power laser beams of not more than 5&nbsp;mW can cause permanent retinal damage if gazed at for several seconds; however, the eye's [[blink reflex]] must be intentionally overcome to make this occur. Such laser pointers have reportedly caused [[afterimage]]s, [[flash blindness]] and [[Glare (vision)|glare]],<ref name=princeton>[https://web.archive.org/web/20110809020724/http://web.princeton.edu/sites/ehs/LabPage/laserpointersafety.htm Princeton University: Safety Recommendations for Laser Pointers]. Web.princeton.edu. Retrieved on 15 October 2011.</ref> but not permanent damage, and are generally [[laser safety|safe]] when used as intended.

A high-powered green laser pointer bought over the [[Internet]] was reported in 2010 to have caused a decrease of [[visual acuity]] from 6/6 to 6/12 (20/20 to 20/40); after two months acuity recovered to 6/6, but some retinal damage remained.<ref name=damage1/><ref name=damage2/> The US FDA issued a warning after two [[anecdotal report]]s it received of eye injury from laser pointers.<ref name=princeton/>

Laser pointers available for purchase online can be capable of significantly higher power output than the pointers typically available in stores. Dubbed "Burning Lasers", these are designed to burn through light plastics and paper, and can have very similar external appearances to their low-power counterparts.<ref name="NEJM">{{cite journal|title=Retinal Injuries from a Handheld Laser Pointer |doi=10.1056/NEJMc1005818|journal= N Engl J Med |volume= 363|issue=11|pages=1089–1091|year=2010|last1=Wyrsch|first1=Stefan|last2=Baenninger|first2=Philipp B.|last3=Schmid|first3=Martin K.|pmid=20825327|doi-access=free}}</ref><ref name="Bloomberg">Gordon, Serena (8 September 2010) [http://www.businessweek.com/lifestyle/content/healthday/642932.html Kids Playing With Laser Pointers May Be Aiming for Eye Trouble; Teen boy damages retina with Internet-purchased 'toy,' doctors say] {{webarchive |url=https://web.archive.org/web/20120416060942/http://www.businessweek.com/lifestyle/content/healthday/642932.html |date=16 April 2012 }}. Bloomberg BusinessWeek</ref> Because of their high power, many online retailers have warned high-power laser pointer users not to point them at humans or animals.

Studies in the early twenty-first century found that the risk to the human eye from accidental exposure to light from commercially available class IIIa laser pointers having powers up to 5&nbsp;mW seemed rather small; however, prolonged viewing, such as deliberate staring into the beam for 10 or more seconds, can cause damage.<ref>{{cite journal|title=Assessment of Alleged Retinal Laser Injuries|journal=Arch Ophthalmol|year=2004|volume= 122|pages= 1210–1217|issue=8|doi=10.1001/archopht.122.8.1210|pmid=15302664|last1=Mainster|first1=M. A.|last2=Stuck|first2=B. E.|last3=Brown Jr|first3=J|doi-access=}}</ref><ref>{{cite journal|title=Retinopathy From a Green Laser Pointer: a Clinicopathologic Study |journal=Arch. Ophthalmol. |year=2005 |volume=123 |pages=629–633 |pmid=15883281|doi=10.1001/archopht.123.5.629|issue=5|last1=Robertson |first1=D. M. |last2=McLaren |first2=J. W. |last3=Salomao |first3=D. R. |last4=Link |first4=T. P. |doi-access=free }}</ref><ref>{{cite journal|author=Sliney DH, Dennis JE|title=Safety concerns about laser pointers|journal= J. Laser Appl. |year=1994|volume=6|issue=3|pages=159–164|doi=10.2351/1.4745352|bibcode=1994JLasA...6..159S}}</ref><ref>{{cite journal |title=Assessment of Alleged Retinal Laser Injuries |pmid=15302664 |journal=Arch Ophthalmol |year=2004 |volume=122 |pages=1210–1217|doi=10.1001/archopht.122.8.1210|issue=8|last1=Mainster |first1=M. A. |last2=Stuck |first2=B. E. |last3=Brown Jr |first3=J |doi-access= }}</ref>

The UK Health Protection Agency warns against the higher-power typically green laser pointers available over the Internet, with power output of up to a few hundred milliwatts, as "extremely dangerous and not suitable for sale to the public."<ref>[http://www.hpa.org.uk/web/HPAweb&HPAwebStandard/HPAweb_C/1195733794576 UK Health Protection Agency Information Sheet on Laser Pointers] {{webarchive|url=https://web.archive.org/web/20080613070927/http://www.hpa.org.uk/web/HPAweb%26HPAwebStandard/HPAweb_C/1195733794576 |date=13 June 2008 }}. Hpa.org.uk (21 May 2010). Retrieved on 2011-10-15.</ref>

===Infrared hazards of DPSS laser pointers===
{{More citations needed|date=December 2018}}
Lasers classified as ''pointers'' are intended to have outputs less than 5&nbsp;mW total power ([[Laser safety|Class 3R]]). At such power levels, an IR filter for a DPSS laser may not be required as the infrared (IR) output is relatively low and the brightness of the visible wavelength of the laser will cause the eye to react (blink reflex). However, higher-powered (> 5&nbsp;mW) [[DPSS]]-type laser pointers have recently become available, usually through sources that do not follow laser safety [[Laser safety#Regulations|regulations]] for laser packaging and labeling. These higher-powered lasers are often packaged in the same pointer-style housings as regular laser pointers, and usually lack the IR filters found in professional high-powered DPSS lasers, because of costs and additional efforts needed to accommodate them.<ref>{{Cite journal|last1=Galang|first1=Jemellie|last2=Restelli|first2=Alessandro|last3=Hagley|first3=Edward W.|last4=Clark|first4=Charles W.|date=2010-08-02|title=A Green Laser Pointer Hazard|journal=NIST |arxiv=1008.1452|url=https://www.nist.gov/publications/green-laser-pointer-hazard|language=en}}</ref>

Though the IR from a DPSS laser is less collimated, the typical [[neodymium laser|neodymium-doped crystals]] in such lasers do produce a true IR laser beam. The eye will usually react to the higher-powered visible light; however, in higher power DPSS lasers the IR laser output can be significant. What poses a special hazard for this unfiltered IR output is its presence in conjunction with laser safety goggles designed to only block the visible wavelengths of the laser. Red goggles, for example, will block most green light from entering the eyes, but will pass IR light. The reduced light behind the goggles may also cause the pupils to dilate, increasing the hazard to the invisible IR light. Dual-frequency so-called YAG laser eyewear is significantly more expensive than single frequency laser eyewear, and is often not supplied with unfiltered DPSS pointer style lasers, which output 1064&nbsp;nm IR laser light as well. These potentially hazardous lasers produce little or no visible beam when shone through the eyewear supplied with them, yet their IR-laser output can still be easily seen when viewed with an IR-sensitive video camera.

In addition to the safety hazards of unfiltered IR from DPSS lasers, the IR component may be inclusive of total output figures in some laser pointers.

Though green (532&nbsp;nm) lasers are most common, IR filtering problems may also exist in other DPSS lasers, such as DPSS red (671&nbsp;nm), yellow (589&nbsp;nm) and blue (473&nbsp;nm) lasers. These DPSS laser wavelengths are usually more exotic, more expensive, and generally manufactured with higher quality components, including filters, unless they are put into laser pointer style pocket-pen packages. Most red (635&nbsp;nm, 660&nbsp;nm), violet (405&nbsp;nm) and darker blue (445&nbsp;nm) lasers are generally built using dedicated laser diodes at the output frequency, not as DPSS lasers. These diode-based visible lasers do not produce IR light.