A comprehensive resource for safe and responsible laser use

Frequently Asked Questions

General interest questions

Below is more information about laser pointer safety in general. There is a separate FAQ for "doubters" -- people who think concern over laser pointers is overblown. Many aviation-related questions are on the FAQ for doubters page.

If you have a question not answered by either FAQ, please contact us using the link at the very bottom of this page.

  • What is the biggest problem with laser pointer misuse?
    The most serious problem by far comes when laser pointers are aimed towards aircraft. People have been arrested and even jailed for shining lasers towards planes and helicopters. (See the aviation incident news page for many articles about aircraft/laser incidents, and the Sentences page for fines and jail terms.) So don't do it!
  • What other laser pointer problems are there?
    • Laser pointers have been aimed at cars, busses, trains, boats, barges, and ferries. Just as with aircraft, this can distract or temporarily blind a motorist or driver — this is obviously unsafe.
    • At sporting events, spectators have aimed laser pointers at players such as football goalies. This is unsportsmanlike (to say the least!) as well as a potential eye hazard for the player.
    • At concerts and movie theaters, sometimes an audience member will think it is funny to wave the laser dot around on the stage or screen.

    Such misuse will backfire. When ordinary citizens are distracted, harassed, annoyed, or temporarily blinded, they are more inclined to support restrictions or bans on laser pointers.
  • Have laser pointers ever caused a vehicle or aircraft accident?
    Lasers have been misused by aiming at vehicles or aircraft for decades. This website’s author is aware of vehicle-aiming incidents as early as 1981. Regarding aircraft, from 2004 when the FAA began requiring pilots to report laser illuminations, through May 2016, there have been over 30,000 incidents in the U.S. where lasers were aimed at pilots.

    In the discussion below, “accident” is defined as an incident that results in actual damage to the vehicle, aircraft or property; or that results in a bodily injury (e.g., anything beyond a claimed laser light injury to the eyes). In contrast, “incident’ is something potentially hazardous or dangerous, which does not result in property damage or bodily injury.

    For example, laser light in a pilot’s eyes may have caused a missed approach and a subsequent go-around. While this incident is cause for serious concern, it did not result in an aircraft accident.

    Lasers causing vehicle accidents

    • The website author is aware of one documented accident caused by a laser pointer. This comes from a 1999 Springfield, Missouri laser pointer ordinance that references a local accident: “a three-car collision, where a young man pointed a laser light into the car ahead of him and startled the driver, causing him to slam on his brakes and create a pileup.”

    • In 1998, a man going nearly 100 mph caused a five-vehicle crash that killed four teens in Morgan Hill, California. Prior to the crash, the man was aiming a laser pointer at other cars. According to the Associated Press, “Law enforcement officials partially blamed the accident on the laser pointer”, although a SF Gate story filed at the same time was less certain: “[I]investigators were trying to find out what role, if any, the laser pointer may have played in the crash.”

    • The author has heard informally of five vehicle accidents in France, around 2014, caused by laser visual interference but has not yet been able to find documentation.

    This website’s has a page that lists some non-aviation laser incidents. The stories on this page have tags that include Car, Motorist, Road rage and Driver. Clicking on these tags to find all relevant articles brings up stories where vehicles are targeted by lasers. In some of these, there are incidents including claimed eye injuries. There are even some laser-related deaths, such as when youths suspected of lasering a police car died after being chased by police, or when taxi drivers, angry at teens aiming lasers at them, stabbed a youth to death.

    However, as of June 2016 there are no stories listed where the light from a laser directly or indirectly caused a vehicular accident, except for the 1999 Springfield, Missouri accident and (perhaps partially) for the 1998 Morgan Hill, California crash described above.

    Lasers causing aircraft accidents

    • As of June 2016, there have been no documented cases of the light from a laser causing aircraft accidents (e.g., a crash or injury-producing incident).

    Anyone with links to documented cases of vehicle or aircraft accidents is asked to email the author (see “Contact us” link at the bottom of any page).
  • When does a laser pointer get powerful enough to be dangerous?
    There is no specific threshold between a "safe" laser beam, a potentially hazardous one, and a clearly dangerous beam. The following are some guidelines.

    Bright Light Hazard

    Even a "legal" (in the U.S.) 5 milliwatt laser pointer can be a potential hazard if the light distracts or temporarily flashblinds a person such as a pilot. This is why you NEVER aim a laser pointer at an aircraft, or the driver of a vehicle.

    Eye Hazard

    For direct damage to the eye, the exact severity will be due to many factors: beam power, exposure time, beam/eye relative motion, distance from the laser, and retinal injury location.

    • If a person deliberately stares into a laser, even a small 1 milliwatt beam could cause a spot on the retina.
    • Fortunately, the eye's natural "aversion response" causes a person to involuntarily blink and/or turn away from a bright light. Taking this into account, an accidental exposure to a 5 milliwatt beam is considered tolerable, as long as the person is not overriding their blink reflex. A 1998 Lancet article by Mensah, Vafidis and Marshall states “A 5 mW laser with high retinal irradiance is too weak to cause retinal damage, even if shone in the eye for several seconds.”
    • After some point, even blinking and moving isn't fast enough to prevent injury. As a very rough approximation for laser pointer use, above 10 milliwatts the potential hazard from general use outweighs the benefit of a brighter beam.
    • At around 100 milliwatts, an accidental exposure at close range may cause a change to the retina which can be defined as an eye injury. The victim may or may not notice it depending on where the spot is on the retina. The injury may heal after a few days or weeks if the exposure is not too severe. According to the 1998 Lancet article, “Between 100 and 500 mW of diode energy is required to produce a clinically retinal burn.”

    Skin Hazard

    At around 150 milliwatts, the beam from a laser can be felt on the skin, depending on the beam focus, skin color (absorption), etc. At roughly 500 milliwatts, the laser's beam begins to be a skin burn hazard if the person is within a few meters of the beam.

    Incidentally, even powerful industrial lasers cannot cause deep burns, severed limbs, gun-type injuries or other effects seen in science fiction movies. While multi-watt laser beams are definitely serious eye hazards, they are ineffective at causing incapacitating body injuries.
  • On a CSI:Miami episode, a laser pointer brought down a plane by injuring the pilots' eyes about 2 miles away. Is this possible?
    The CSI:Miami scenario is not plausible. A legal, off-the-shelf laser pointer like the one on the show has a maximum power of 5 mW. A beam from this laser is a distraction to pilots out to about 2.2 miles. However, the light level would not cause veiling glare, flashblindness or (especially) eye injuries. The producers and researchers for CSI:Miami took a lot of dramatic liberties in this case! (The episode is "Money Plane", first aired March 7, 2005.)

    However, it is good to get the public informed about the general idea that laser pointers can potentially be hazardous. This is why you should never aim a laser at or near an aircraft.
  • Can the laser scanner at a checkout injure my eyes?
    The very short answer is “no”. Here are more details:

    In stores you often see a hand-held scanner which is aimed at the Universal Product Code “stripes” on a package. Or you see a window in the checkout counter, over which the UPC code is passed.

    Sometimes LEDs are used as the light source, but often lasers are used. You can tell if it is a laser because there will be a pattern or geometric shape made up of thin lines; this is one example:

    Image via Wikipedia, by Alessio Damato

    Having the scanned laser light go into your eyes is not hazardous. In the U.S., the laser power for a checkout scanner must be below 5 milliwatts. This is the same as the power limit for a laser sold as a pointer.

    It is difficult enough for a 5 mW laser pointer to cause damage to a person’s eyes. You pretty much have to stare at the beam at very close range, making a deliberate exposure to the single “dot” of the pointer.

    For a store’s laser scanner, the power is further spread out by being scanned rapidly over an area. This means that the “dot” of laser light cannot remain on the same area of the retina and build up heat.

    While having a laser scanned pattern in your eyes can be annoying (and rude if deliberately done by a cashier), there is no cause for concern.

    A very quick test is to close your eyes and see if you have any afterimage from the exposure (similar to the afterimage caused by a camera flash, or the sun glinting off a reflective object.) Normally you should not have an afterimage, or it should fade in less than a minute. If you do have a longer-lasting afterimage, or any new spots in your visual field, you may wish to have an eye exam by an ophthalmologist or a retinal specialist. Even then, this is suggested only for an extraordinary exposure such as deliberately staring into the scanner, or if the scanner is suspected to be malfunctioning and is brighter than normal.

    It would not be economical to require laser scanners to have additional safety features, such as eye detection (to turn off if they see an eye) or a direction detector (to turn off unless the laser is facing downwards). Between the low power of the laser itself, plus the added safety of a constantly-moving beam, an accidental or unwanted exposure is not hazardous.

    (Thank you to L.B., who asked this question Feb. 10, 2016)

  • Aircraft can look like stars. What is the best way to point out stars in the night sky?
    A slow-moving, far-away aircraft can look like a star. If you are doing astronomy pointing at a "star talk", use the laser pointer to circle unknown or faint objects. Don't point directly at them unless you are sure it is a star (i.e., Orion's belt or the Big Dipper handle). For more information on star pointing applications, see this page.
  • In the U.S. it is illegal to aim at the flight path of an aircraft. Given that just about anywhere in the sky there could be a flight path, is this a problem for legal laser use?
    The U.S. law signed by President Obama in Feb. 2012 makes it illegal to knowingly aim laser pointer beams at an aircraft, or at the flight path of such an aircraft.

    Fortunately for amateur astronomers or other legitimate outdoor users, there is little chance of having the flight path clause invoked by prosecutors, for the following reasons:

    • The cases that are brought for trial are ones where a person deliberately aimed at an aircraft. Someone on the aircraft saw beams coming near or at the aircraft. They then either called police, or they were the police.

    • In most prosecuted cases, there are multiple beam illuminations involved -- e.g., a laser is tracking the aircraft and illuminates it multiple times. It is rare for any single-illumination incidents to be identified or prosecuted.

    • Usually the person prosecuted has some sort of antisocial characteristic such as a criminal record, being on probation or in a gang, being hostile with arresting officers, possessing drugs at the time of arrest, etc.

    There are only a few prosecuted cases involving a claimed or actual astronomy use.

    In an abstract sense, any laser beam in the sky is probably touching some aircraft's flight path. But this has not been the type of case that worries safety experts, or the type of case that prosecutors bring to trial.
  • How is a laser pointer different from other lasers?
    Surprisingly, there is no generally accepted definition of a laser "pointer".

    In the U.S., the federal FDA/CDRH indicates that pointers are "hand-held lasers that are promoted for pointing out objects or locations" with output power less than 5 milliwatts. According to FDA, promotion of lasers above 5 milliwatts "for pointing and amusement" violates FDA requirements and U.S. law.

    (Some may consider this to be a loophole. If a hand-held laser is not promoted for pointing or amusement purposes, then it can legally be sold.)

    Starting in 2010, FDA/CDRH appeared to be closing the loophole by defining handheld portable lasers as "surveying, leveling and alignment" (SLA) lasers. Since FDA/CDRH has authority over SLA lasers, the agency may use this new regulatory interpretation to limit the sale of handheld portable lasers over 5 milliwatts. For more information, see the page FDA authority over laser pointers and handheld lasers.

    In New South Wales (Australia), a pointer is a Schedule 1 Prohibited Weapon: "A laser pointer, or any other similar article, consists of a hand-held, battery-operated device with a power output of more than 1 milliwatt, designed or adapted to emit a laser beam and that may be used for the purposes of aiming, targeting or pointing."

    In Victoria (Australia), a pointer is also a prohibited weapon. It is defined as: "A hand-held, battery-operated article designed or adapted to emit a laser beam with an accessible emission limit of greater than 1 mW."

    If one wants to own a laser with greater power, it is easy enough to do so. There is the inconvenience of having to run off of mains (AC) power, but then again AC outlets are everywhere, including automobiles (using a low-cost inverter like the one shown below).

    car inverter power adapter

    Also, if an evil person wanted to do harm with a laser beam, it would be easy for them to use a regular laser. A ban or restriction on pointers would have no effect on them.

    More information on existing and suggested definitions of “laser pointer” is on the page “If you are writing a laser law…”.

  • What is the maximum allowed power?
    There is no "maximum" power in the U.S. and many other countries. A person can buy a laser of whatever power they want, even tens of watts.

    For use by the general public as a laser "pointer", the maximum is supposed to be 5 milliwatts (U.S.) or 1 milliwatt (U.K.). Obviously, much more powerful handheld lasers are available. As long as they are not advertised for pointing or beam-display purposes, sale of lasers above 5 mW is legal in the U.S. Also, it can be difficult or low priority for law enforcement to track down illegally-marked or distributed lasers.

    For more information, see the Rules for U.S. consumers page.
  • What should I do if I have an "illegal" pointer or high-powered laser?

    Safety considerations

    From a safety standpoint, what you should do depends on the laser's power. There is no need for a laser over 5 milliwatts for most pointing purposes. For astronomy pointing purposes, you can see the beam of a green lasers in the 4 to 20 mW range. Even for most experimenters and enthusiasts, there is usually no need for above 50 mW (exceptions: popping/burning experiments or home laser shows).

    If you have a laser in this "extra caution range" of roughly 5 to 20-50 mW, you can discard the laser if you want, or use it with added care. Be especially careful not to annoy or injure bystanders. It is one thing if you are hurt, it is another thing to involve someone else.

    If the laser is above 20-50 milliwatts, hazards are increased. Except for mature and careful experimenters, we recommend that you safely discard the laser. LaserPointerSafety.com does not recommend that the general public own or use Class 4 lasers, which are 500 milliwatts and above (above 1/2 watt). If you must have a high-powered laser for some reason, be sure to read and always follow the safety warnings.

    There is good information on the page Don't aim at head and eyes; be sure to download and read the appropriate PDF flyer for your laser's power level.

    Legal considerations

    From a legal standpoint, to find out more about whether you can keep an illegally labeled or manufactured laser, see the Rules for U.S. consumers page.
  • Are high-power laser pointers required to have specific features?
    In the United States, lasers above 5 mW (Classes 3B and 4) must have proper labeling, an emission indicator, and an interlock with a key or pin that prevents emission if the pin/key is removed. Note that this means the laser can remain continuously on as long as the pin/key is inserted and the switch or button is turned on (there does not have to be a momentary pushbutton that turns off when pressure is released). Also, lasers above 5 mW cannot be marketed as "laser pointers" or for purposes of surveying, alignment or pointing.

    There may be some confusion between the original U.S. laser laws, 21 CFR 1040.10 and 1040.11, and CDRH's Laser Notice #50, which was first issued in 2001 and was updated in 2007. Laser Notice #50 allows U.S. marketing of laser products certified using international standard IEC 60825-1. This removes the requirement for a shutter, and for an emission delay circuit. Also, warning labels can follow IEC instead of CDRH, if desired. This harmonizes U.S. law with international standards.
  • What is the maximum power needed for laser pointing?
    50 milliwatts is probably the maximum needed power for almost any laser pointing use.

    For seeing the laser "dot" on a wall or surface indoors or in dim light, 5 milliwatts of green is fine. The most demanding general-use pointing application is for pointing out objects in bright sunlight such as a daytime city architecture tour, and for pointing out stars at night when it is necessary to see the beam in mid-air. For these uses, 5-25 mW should be fine, with a maximum of 50 mW for tough situations (high brightness, showing stars to a large group).

    The Norwegian Radiation Protection Authority states that 20 mW is the limit: “It is not known that laser pointers that are stronger than approx. 20 milliwatts can be used for anything useful. The effect of laser pointers used to point out constellations and like at night, should not exceed a maximum of 20 milliwatts. The reason is that the beam can destroy the night vision of the spectators so that they can no longer perceive weak starlight.” (For Norway’s regulations, see the International laws page, then click on the item “NORWAY: Possession and use regulated.”)

    If you like to pop balloons, ignite matches, or put the laser through textured glass for a private light show in your home, you may want a more powerful laser. But this is no longer a POINTER application.
  • What laser color is best?
    A green laser is the most visible. The eye sees green better (more efficiently) than other colors. A 5 mW green laser will appear much brighter than a 5 mW red or blue laser.

    Note that in terms of eye injury hazards, the color does not matter. More milliwatts means a greater potential eye hazard, no matter what the beam color. (This is for visible lasers; for infrared or ultraviolet lasers, the primary injury area is the cornea and not the retina.)
  • I want to make my own laser to burn things. Is this dangerous?
    Yes, you need to know about the potential dangers before deciding to build such a laser. These include obvious hazards such as too much visible light, and non-obvious hazards, such as the possibility of too much invisible (infrared) light. For much more information, visit the DVD flashlight hack safety warning page.
  • Is a laser pointer ban effective?
    Banning or severely restricting laser pointers seems like a simple, attractive solution to misuse such as pointing at aircraft. However, there are a number of problems:

    • It is hard to effectively define laser pointers. To give one example, if "battery powered" lasers are banned, it still is relatively easy to find AC outlets in public spaces, or to use a low-cost inverter to run a laser off a car's 12-volt power socket.

    • It is hard to enforce. In a world with Internet sales by mail, and easy world travel, it becomes difficult to check every package or person at Customs to see if they have a laser pointer.

    • It does not stop someone who really wants a laser. It is easy to get new or used lasers, either by themselves or built into equipment. DVD and Blu-Ray players, and some video projectors, contain powerful laser diodes. If hobbyists can get these, so can anyone with evil intent. Said another way, "When laser pointers are outlawed, only outlaws will have laser pointers."

    • It stops legitimate use of laser pointers by teachers, business people, astronomy educators and others who find a laser ideal for pointing out objects.

    • "It is like banning the kitchen knife because we have people using the knives incorrectly," according to Professor Hans Bachor, president of the Australian Optical Society, as quoted by the Australian Broadcasting Corporation.

    It is unclear whether a laser pointer ban significantly reduces laser incidents. For example, Australia banned laser pointers above 1 milliwatt in 2008, yet the number of aircraft illuminated by lasers rose significantly over the next four years. While the subsequent three years did show a reduction, the rate was still about 3.5 times that of the pre-ban illuminations.

    Pic 2016-06-22 at 11.58.31 AM

    Anyone who wants to deliberately use a laser for bad purposes can easily do so, ban or no ban. For example, on a per capita basis, Australia's rate is 2.8 times the U.S. rate despite the ban. While there may be other factors, this is an indication that bans may not work. (We have a list of aviation-related laser pointer incidents in Australia.)

    In 2013, it was reported that Australia's bans had the effect of making online pointers more unsafe. Sellers illegally understated the power of lasers, so they could be imported. 95% of pointers tested were above the Australian limit of 1 mW, and 78% of those tested were also above the US limit of 5 mW. Persons interested in whether bans work should read the article "Ban on laser pointers has been a 'detriment' to safety.

    We have additional information on the page Tax handheld lasers and pointers?

    For an interesting perspective, see this online debate about banning laser pointers. Note that there are some inaccuracies or misconceptions in the material so do not rely completely on the arguments and data in this online debate.

    The Economist magazine printed an article "The Case for the Defence" on October 30 2013, stating "But no aeroplane accident has ever been convincingly attributed to a laser pointer, and numerous fail-safes make such an accident highly unlikely. Also, high-powered laser pointers are fun and useful—especially for stargazers. It would be a shame to see them banned because of a few foolish people. One hopes that politicians will see the value in these sorts of products. One does, at least: earlier this month the governor of New Jersey, Chris Christie, vetoed a bill that would have banned even low-powered laser pointers in his state."

  • How does laser misuse compare with knife misuse?
    Laser misuse pales next to knife misuse. In 2010 there were 130,000 assaults yearly with knives and cutting instruments. Compare this with with the 7,703 FAA-reported laser illuminations in 2016. Also, compare the over 2 million serious knife injuries each year with the handful of eye injuries reportedly caused by handheld lasers.

    Certainly laser illuminations and injuries should be reduced as much as possible, especially with regard to aiming at aircraft. But the above data helps to give some perspective on the relative risk of these two handheld devices. Statistically, a person is much more likely to be injured by or assaulted with a knife or blade, than to be injured by a pointer or to be on an aircraft illuminated by a laser.

    (For detailed statistics on deaths and injuries caused by knives, see the "Knives" section of the Risks of pointers and other items webpage.)
  • I am upset and want to pass a law against lasers. Where do I start?
    Any law restricting laser equipment or usage needs to be carefully considered. It should effectively address the problem without infringing on rights of legitimate users. This page has some suggestions. In addition, check out the list of selected international and U.S. laser laws. You can read both well-written statutes, and poorly-worded ones.

    You may want to have SAE G-10T take a look at your proposed law, to help provide suggestions for improvement.

  • What is the SAE G10T and why should I care?
    The SAE G10T Laser Hazards Subcommittee studies laser uses in airspace. Members include laser safety experts, pilots, military safety officers, and laser users for industry, military, research, and displays. They write reports such as ARP5293, “Safety Considerations for Lasers Projected in the Navigable Airspace.” Their recommendations are often adopted by aviation authorities such as the U.S. FAA.

    The G10T subcommittee is one of the few groups monitoring laser/aircraft incidents. If they called for restrictions or a ban on laser pointers, their recommendations would carry great weight.

    More information is on this website's page SAE G10T Laser Hazards Subcommittee.
  • How can I support LaserPointerSafety.com?
    This website is a one-person operation that takes a substantial amount of time. We welcome assistance from sponsors and supporters. For more information, see our Sponsorship opportunities page.
  • Why is ILDA helping sponsor this website?
    The International Laser Display Association represents manufacturers of laser shows and projectors. While many ILDA members own and enjoy laser pointers, the pointers are not needed in creating shows.

    ILDA does not have an official position on laser pointers, or on laser misuse. ILDA as a sponsor has provided some resources for this website, as a public service. One reason is that, if the general public sees pointers as dangerous, this could have an indirect negative impact on laser show productions.