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The study looked at 77 case reports of laser eye injuries in children. In four of the cases there were reported psychological or behavioral issues.
In addition, the authors had experience with four children with laser eye injuries; in three of these cases there were psychological or behavioral issues.
One of the authors sent a survey to 990 consulting ophthalmologists in the U.K. This found 159 cases of macular injury due to "misuse of a handheld laser device," with 80% of those injured being children or teenagers. In 35% of the cases, the injury was self-inflicted; in 36% it was caused by a third-party. (The remaining 29% seem to be uncategorized although the paper notes that "there were no cases of assault reported." In 67% of the cases where the laser power was known, it was under 50 milliwatts.
The paper cautions that the actual number of laser injuries seen by the ophthalmologists may be higher: "A limitation was the poor response rate and thus data so obtained do not provide the true incidence and clinical features of such cases."
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It showed that 48 percent of Canadians over the age of 12 either used or were exposed to lasers, annually.
Of those who reported using a laser product, 1.1% reported discomfort or injury.
[LaserPointerSafety.com analysis: Based on 2016 Canadian census data, there were 29,312,165 Canadians age 15 or older — data was not available on age 12+. If 48% of these 29 million Canadians used or were exposed to lasers, that would be just over 14 million people. If 1.1% of them experienced discomfort or injury, that would be about 155,000 Canadians with laser discomfort or injury.]
Returning to the Statistics Canada study, of the discomfort/injury cases:
- 41% were for skin injuries "such as rash, itch or pain," while 59% were for eye injuries "such as itchiness, pain, visible floating objects, blurred vision, burn, flash blindness, excessive watering or loss of sight."
- In 64% of cases, the discomfort or injury lasted less than two days; in 34%, it lasted more than two days.
- The discomfort/injury was caused by the person's own use of the laser in 25% of cases, and by someone else's use in 75% of cases.
- 39% of the discomfort/injury cases were caused by cosmetic treatments, 26% were caused due to laser pointers, and 34% were caused by "other" which included surveying tools, entertainment lasers, materials processing, and scanners.
The study analyzed published eye injury case reports since 1999, and concluded:
"…the majority involved the misuse of a handheld battery-operated laser product by an adult or a child. Most of these injuries were the result of irresponsible use or deliberate staring at a laser by a child, or the result of the inappropriate use of a high-powered laser device (Class 3B or 4) in an 'uncontrolled environment'....In the cases reported in 2014 that included long-term follow-up injury reporting, about one-half of the ocular injuries resolved within one to two weeks, with the other 50% of patients sustaining longer-term visual impairments."
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The information was at the end of a story about an Indianapolis boy who injured his eye when playing with a laser pointer five years ago, when he was 12 years old. The story is summarized here.
From RTV6 The Indy Channel
“We already had several such cases (a laser injury of the eye retina) in the State Border Guard Service and in the National Guard. We are now developing countermeasures. We do not fully understand what they use, but we are already working on the instructions what it could be. We will install the appropriate filters, devices, use appropriate glasses,” Avakov said.
He reported on four cases of the laser injury of border guards and national guardsmen.
“The use of such weapons is a barbarous situation. We will discuss it at the international level,” Avakov emphasized.
From Kyiv Post
The Coast Guard cannot use standard laser eye protection, such as is used in laboratories and industry, because it blocks too much light. One of the options the RDC is looking at is “a flexible optical filter that is reflective of lasers only and has just a slight tint, so it doesn’t interfere with the pilot’s visibility. The material can be applied to any transparent surface, such as the cockpit windshield, to deflect harmful laser beams and prevent them from reaching the inside of the cockpit.”
The chief of the Coast Guard’s Safety Program Management Division indicated eyewear or visors would be short-term solutions, and laser protective coatings for the aircraft would be a long-term solution.
According to Coast Guard information, “[o]nce finalized, the RDC findings will be integrated into an ongoing laser eye protection project the Office of Safety and Environmental Health is conducting in partnership with the Naval Aeromedical Research University in Dayton, Ohio, and the Air Force Research Laboratory at Wright-Patterson Air Force Base in Ohio.”
From a February 21 2018 blog post from the U.S. Coast Guard. Click the “Read more” link for the full blog text. Thanks to George Palikaras for bringing this to our attention.
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Background: Recent years have seen a marked increase in laser-pointer-related injuries, which sometimes involve severe retinal damage and irreversible visual impairment. These injuries are often caused by untested or incorrectly classified devices that are freely available over the Internet.
Methods: We reviewed pertinent publications retrieved by a systematic search in the PubMed and Web of Science databases and present our own series of clinical cases.
Results: We identified 48 publications describing a total of 111 patients in whom both acute and permanent damage due to laser pointers was documented. The spectrum of damage ranged from focal photoreceptor defects to macular foramina and retinal hemorrhages associated with loss of visual acuity and central scotoma. On initial presentation, the best corrected visual acuity (BCVA) was less than 20/40 (Snellen equivalent) in 55% of the affected eyes and 20/20 or better in 9% of the affected eyes. Treatment options after laser-pointer-induced ocular trauma are limited. Macular foramina and extensive hemorrhages can be treated surgically. In our series of 7 cases, we documented impaired visual acuity, central visual field defects, circumscribed and sometimes complex changes of retinal reflectivity, and intraretinal fluid. Over time, visual acuity tended to improve, and scotoma subjectively decreased in size.
Conclusion: Laser pointers can cause persistent retinal damage and visual impairment. In view of the practically unimpeded access to laser pointers (even high-performance ones) over the Internet, society at large now needs to be more aware of the danger posed by these devices, particularly to children and adolescents.
From Birtel J, Harmening WM, Krohne TU, Holz FG, Charbel Issa P, Herrmann P. Retinal injury following laser pointer exposure—a systematic review and case series. Dtsch Arztebl Int, 2017 DOI: 10.3238/arztebl.2017.0831. Original in German, translation in English.
Here is the same data, plotted to show the average number of illuminations per day, during each year:
For additional charts and statistics, click the “read more” link.
In addition, “new measures are also being introduced to tackle the sale of unsafe pointers, including more stringent testing.”
The move was supported by the British Air Line Pilots Association (BALPA).
It may help reduce the number of laser pen illuminations of trains (578 incidents were reported between April 2011 and November 2017) and eye injuries (more than 150 reported since 2013, mainly involving children).
Consumer Minister Margot James said the ministry is “going further than ever before” to police the sale of unsafe lasers.
The Argus quoted Professor John O’Hagan, of Public Health England’s laser and optical radiation dosimetry group.He said: “Over time we have become increasingly concerned about the dangers of growing numbers of unlabelled and incorrectly labelled high power laser pointers being bought by the public. It is tragic that we continue to see eye injuries, especially in children. Laser safety experts at Public Health England have worked closely with local authorities in stopping large numbers of these lasers reaching UK consumers. The extra protections proposed should help even further - if you have a laser and you don’t need it, remove the batteries and get rid of it.”
From The Telegraph and The Argus. The stories seem to be a result of the U.K. government publishing, on January 8 2018, a response to their fall 2017 Call for Evidence. The government response included the increased import enforcement actions.
See also the December 2017 news of a new U.K. law that provides stronger penalties for aiming at aircraft. The new import/consumer initiative seems to be part of the government thrust against illegal and overpowered laser pens.
Michael Reeves’ tongue-in-cheek narration states “…it’s really doing its job of lasering me in the eye which is the real innovation here. To my pleasant surprise I found that this machine also solved another of society's problems; the fact that you're not seeing little tiny dots in your vision all day long. I know where to go when I wanted to see little dots, now I can't focus on anything.”
The laser in the video looks substantially more powerful than the U.S. FDA limit of 5 milliwatts. (However, it can be difficult to estimate laser power from a video. For example, the camera may be more red-sensitive than human eyes which might explain why the beam seems so large and bright.)
Anyone doing this should be aware of the problem of laser pointers often being more powerful than the label states, and more powerful than the U.S. limit of 5 mW.
Fortunately for Reeves’ vision, the laser is mechanically aimed by two devices that move it left-right and up-down. This makes the aiming relatively slow and lagging the facial recognition, so the beam can be dodged much of the time. He moves to avoid the beam, and is hit in or very near to an eye about once every couple of seconds.
The screenshot below shows the camera (blue arrow) and a laser module mounted on two servos (yellow arrow).
As befits a student budget, the housing is an old pizza box. Reeves wrote the facial recognition and aiming program in C#, using Emgu CV, a .Net wrapper for the OpenCV computer vision library.
In about a day, the video received 80,000 views as well as being featured at tech blog The Verge.
From The Verge. Original YouTube video here.
UPDATED April 19 2017: Michael Reeves told C/Net “My eyes are fine. A lot of people seem concerned about that, which I admit is warranted. I used a 5 mW laser diode, and never had it in my vision for more than a fraction of a second."
The data shows that pilots reported eye effects or injuries in less than 1% of laser illumination incidents. Flashblindness was the most-reported effect, followed by “Pain, burning or irritation in eye.” Blurriness was also frequently listed, along with unspecified “eye injury.”
In 20% of eye effect/injury cases, the person affected sought medical attention.
From the FAA weekly Laser Report
This was the sole recommendation resulting from a September 5 2015 incident when the two pilots in a Ryanair flight, on approach to Porto Airport, were illuminated by laser light. The pilot flying was distracted and had to use his hand to shield his eyes. The pilot monitoring had temporary flash blindness lasting a few seconds. This contributed to the aircraft’s approach being “unstable.” The pilots executed a missed approach and did a go-around for a second approach; the plane then landed safely.
Portuguese officials told the Irish investigators that there is no law in Portugal against aiming a laser at an aircraft.
In 2014, there were 294 laser incidents reported in Portugal; in 2015 there were 264 such incidents. In 2014, 107 of the incidents occurred at Porto Airport; in 2015 there were 105 incidents at the airport.
From the Irish Examiner
For details, see this LaserPointerSafety.com article in the non-aviation incident section of our news coverage. We are cross-referencing the article in this section as well, for persons who are looking for articles about scientific studies of laser eye injuries.
From mid-July 2016 to late August 2016, more than 570 persons have gone to the main government hospital in Srinagar, Kashmir for treatment of eyes that have been damaged by “birdshot” (lead pellets) fired from shotguns into crowds by Indian security forces trying to break up protests and crowds.
An August 28 2016 New York Times article describes some of the lead pellet-caused eye injuries:
“The patients have mutilated retinas, severed optic nerves, irises seeping out like puddles of ink.”
“[A] patient’s eyelids have been stretched back with a metal clamp, so his eyeball bulges out of glistening pink tissue. The surgeon sits with his back very straight, cutting with tiny movements of his fingers. Every now and then, a thread of blood appears in the patient’s eye socket. The patient is 8 years old…. Slowly, as residents stood around him in hushed silence, the surgeon flattened out the boy’s retina, as thin and delicate as a lace doily, and used a laser to reattach it to the back of his eye.
“In most cases, it became clear, the pellets had burst into through the cornea and out through the retina, leaving little hope of fully restoring vision…. ‘Once it goes in the eye, it rotates like this, and destroys everything there inside,’ Dr. Qureshi said. ‘It’s physics. This is a high-velocity body. It releases a high amount of energy inside. The lens, the iris, the retina get matted up.’”
The author, Ellen Barry, notes that “….most countries do not use them on unarmed civilians, as the pellets spray widely and cannot be aimed…. This year, the use of pellets on Kashmiri protesters increased sharply, with the police firing more than 3,000 canisters, or upward of 1.2 million pellets, in the first 32 days of the protests, the Central Reserve Police Force has said.”
From the New York Times
Australia: Study shows inexpensive green laser pointers are mislabled and significantly over-powered
The researchers purchased eight laser pointers from sources including electronics stores and online stores. They bought four lasers with green beams and four with red beams. The cost of each laser was less than AUD $30 (USD $23).
All of the lasers were advertised to have a maximum output power of either less than 1 mW or less than 5 mW. The green laser pointers’ actual output power measured from 51 to 127 milliwatts. Dr. Fox said “At that upper level, the beam would cause catastrophic retinal damage.”
Apparently much of the green lasers’ power was in the infrared. These types of lasers work by generating non-visible infrared light which is then converted by a crystal into visible green light. A filter is normally used to block the infrared light, and only let the green light through. However, “[t]he research team found that imported laser pointers were poorly made, with manufacturers tempted to skip installing infrared-blocking filters to hold down costs.” The researchers did not measure how much of each lasers’ output was in the visible, and how much was in the infrared.
The 127 milliwatt green laser was labeled as a Class 2 device, with maximum output power of 1 mW. In a previous study from the U.S. NIST, the highest power output they measured was 66.5 mW from a green laser labeled as having a maximum output power of 5 mW.
Three of the four red laser pointers were found to be within the legal limit of 1 milliwatt. The fourth red pointer was about 8.5 milliwatts. The researchers felt that the red lasers’ spots were less focused than green lasers, meaning there was less risk of retinal damage. Also, red lasers use diodes. The maximum power output of these diodes is limited; excessive current will destroy the diode’s lasing capacity instead of providing a more powerful beam.
The researchers noted that “Our experiment raised two very pertinent concerns – first, why were class 3B lasers so easily purchased via the internet without licensing? This suggests that there are many loopholes in the importation of these products and more stringent processes need to be reinforced. Secondly, why did green lasers labeled as Class 2 reach up to a power output of 127mW, effectively attaining a class 3B classification? It is very likely that there is a significant infrared component. This drastic degree of non-compliance suggests that there needs to be more rigorous testing and quality control of these commercially available lasers – merely imposing a power limit of less than 1mW is insufficient.”
The researchers concluded by stating that “Authorities such as the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) and medical authorities such as the Royal Australian and New Zealand College of Ophthalmologists (RANZCO) ought to advocate more strongly for stringent testing, quality control and licensing of green DPSS lasers.”
From an RMIT press release, “Over-the-counter laser pointers a threat to eyesight” and an advance copy of a paper, “Green lasers are beyond power limits mandated by safety standards,” which will be published in the Proceedings of the 2016 IEEE Engineers in Medicine and Biology Conference, online at the IEEE Xplore website. Thanks to Dr. Kate Fox for the paper.
There were 113 flight crew incapacitations in Australia during the study period — an average of about 23 per year. Of these, 15 (13.3%) of the reported incapacitations were due to laser strikes.
The study looked at “high-capacity” and “low-capacity” air transport, as well as general aviation.
During the study period there were 1,316 laser strikes reported to the ATSB in high-capacity operations. Of these, eleven (0.8%) of the laser strikes resulted in flight crew incapacitation.
A summary of the ATSB study is here. The full 30-page PDF document is available online from ATSB or from a local copy here at LaserPointerSafety.com.
But in addition to this declaration, the authors also provided a succinct summary of the current state of consumer laser pointer misuse, and how ophthalmologists should proceed when studying a patient’s laser exposure.
Experts John Marshall, John O’Hagan and John Tyrer began by noting that low-powered Class 2 (less than 1 milliwatt) and Class 3R (1-5 mW) lasers “are not an eye hazard, and even if used inappropriately will not cause permanent eye damage.”
However, consumer laser devices with Class 3B (5-500 mW) and Class 4 (above 500 mW) powers have begun to cause injuries. “….[C]lass 4 devices are capable of causing irreversible retinal damage if directed into the eye over short ranges, up to several metres. Such devices have resulted in foveal injuries in children with current estimates of 150 cases in the UK. The [UK] media has given significant coverage to this growing problem.”
Ophthalmologists were advised that in cases of close up exposure, there may potentially be permanent damage. A detailed examination would be warranted, although there is no treatment to reverse permanent damage.
The hazards from this short range misuse differ from the hazards of aiming a laser towards pilots. Because the laser-to-aircraft distance is typically “hundreds to thousands of metres”, and because of scattering from the windscreen, eye injuries are nonexistent: “Fortunately, these exposures are at irradiances that are incapable of producing irreversible retinal damage even at distances of 100 m.”
They said that only one case of alleged retinal damage has been reported in pilots. [LPS.com note: this is for publicly available reports involving civilian pilots.] The experts concluded the case is suspect for a number of reasons; they do not believe laser targeting caused the alleged injury.
Marshall, O’Hagan and Tyrer turned from injuries to the hazards of distracting pilots with bright laser lights: “Obviously, if such a distraction occurs at a critical time such as during landing then the result could be devastating.”
For ophthalmologists examining pilots, if there are no permanent abnormalities on an Amsler grid test, the physician should not do any detailed eye exam, as this “would only serve to compromise the pilot's vision for a longer period.” The authors noted that pilots may delay seeing an expert for “many hours or a day or so during which there may be a growing psychological element.”
In an interview with CNN, Marshall said the findings on pilot hazards are based on previous laser safety research as well as a new study done with field experiments at a military base over about three years.
In the BJO editorial, the three experts agreed that current laser safety standards and guidelines are based on valid experiments and science. The standards do not need to be revised, “…but clearly further attempts must be made to educate the public.”
The editorial concluded “The European Commission has mandated the European Standardisation bodies to produce a standard specifically for consumer laser products. This should allow enforcing authorities to remove unsafe products from the market. However, compliance by manufacturers will remain an issue, as will direct imports by the public purchasing unsafe laser products over the internet.”
From the British Journal of Ophthalmology editorial “Eye hazards of laser ‘pointers’ in perspective” by John Marshall, John O’Hagan, and John Tyrer, available in HTML text and as a PDF document. Click on the blue “Read More…” link below for an April 19 2016 press release from the BJO summarizing the paper’s findings relative to pilot hazards.
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Examinations were done within three days of the strikes: “Early Treatment Diabetic Retinopathy Study visual acuity, colour vision, visual fields, intraocular pressure, slit-lamp examination, dilated fundus examination, colour fundus photographs, and ocular coherence tomography.”
The paper concluded, “Our study revealed that laser strikes on aircraft did not result in permanent visual functional or structural deficits. However, laser strikes cause immediate visual effects, including glare, flash blindness, and ocular irritation that can interfere with a pilot’s visual function.”
From the Canadian Journal of Ophthalmology, December 2015, Volume 50, Issue 6, pages 429-432. For the full abstract of the study, click the “Read More…” link.
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“An airline pilot presented to our department complaining of a blind spot in the upper left area of his visual field in the right eye (right supero-nasal scotoma) following exposure to a laser beam while performing a landing maneuver of a commercial aircraft. At around 1300 ft (396 m), a blue laser beam from the ground directly entered his right eye, with immediate flash blindness and pain. Spectral domain ocular coherence tomography highlighted a localized area of photoreceptor disruption corresponding to a well demarcated area of hypofluorescence on fundus autofluorescence, representing a focal outer retinal laser injury. Fundus examination a fortnight later revealed a clinically identifiable lesion in the pilot’s right eye commensurate with a retinal-laser burn.”
The paper said the pilot’s symptoms “fully resolved 2 wk later” and that there was no “deficit in visual function.”
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The main body of the 2015 study includes an analysis of the laser power versus the observed injuries.
The authors note “If the availability of the handheld lasers continues to increase, along with higher optical power and lower cost, we expect that the number of severe eye injuries will continue to grow. Also, the distance from which the lasers can be used to disrupt various societal functions, such as air traffic (pilots) and policing will also increase. Almost all the reported cases involve young children and teenagers. There is also a huge overrepresentation by males. Often the lasers are sold as toys and purchased by a relative as a gift to a child. Earlier reports originated almost exclusively from developed countries. This situation has now changed and more and more reports originate from developing countries. The problem is worldwide and hence there is a need to educate and inform the societies of this danger.”
The 47 new cases are listed in an appendix. Here is a random sample listing two of the cases:
Author: Jörgen Thaung, Cesar Lopes and Stefan Löfgren
Publisher: Strål Säkerhets Myndigheten (SSM - Swedish Radiation Safety Authority)
Publication date: December 2015
No of pages: 45
Price per publication: 100 SEK (incl. VAT)
Download: 2015:54 Retinal injuries from handheld lasers: An updated report [2200 kb]
A summary by LaserPointerSafety.com of the study’s objectives, major findings, and conclusion is here. The earlier 2013 study is summarized here and the full SSM document is available here.
Such misdiagnosis has medical and financial consequences from the additional diagnostic workups and DNA sequencing used to detect hereditary genetic disorders such as rod monochromatism, Stargardt disease and occult macular dystrophy.
In addition, the paper describes five cases of where children using laser pointers experienced blurry vision and had eye injuries. “In some cases, the vision was as poor as 20/80, which is bad enough to fail a driving test,” said researcher Dr. Stephen Tsang, who is affiliated with Columbia University and NewYork-Presbyterian Hospital.
Dr. Tsang and his colleagues noted damage patterns similar to tree branches on the children’s retinas:
They suggest that eye-care professionals should ask patients with such patterns if they have been using lasers. Because children may be hesitant to talk in front of their parents, the researchers also suggest talking to a child alone.
A Columbia University press release noted “Since the publication about the five patients, the researchers have seen several more children with laser-induced eye injuries, suggesting that these cases are not isolated phenomena.”
From Columbia University Medical Center Newsroom, Nov. 5 2015. The Ophthalmic Genetics article “Laser induced photic injury phenocopies macular dystrophy” is not yet online as of this date, but can be found at the journal’s website.
The study, reported in the July 2015 American Journal of Ophthalmology, looked at 17 eyes of 17 patients at two institutions, between January 2012 and May 2014. Most were youths (mean patient age 18 years; range: 11 to 30 years old). The eyes were exposed to blue laser light for less than one second, at a mean distance estimated to be about 1 meter from the laser. The time from exposure to the patient visiting the hospital for treatment ranged from two days, to almost 500 days.
Patients were given a full ophthalmic examination, including fundus photography, macular spectral-domain optical coherence tomography, and fundus fluorescein angiography.
The macular holes ranged from 0.17 millimeters to 0.62 mm, with a mean diameter of 0.35 mm.
In 14 of the eyes, surgeons went deep into the eye and removed vitreous gel (a pars plana vitrectomy); this removes clouded gel that may contain blood from the injury. At the same time surgeons also did a procedure called “internal limiting membrane peeling,” which uses an instrument to make a break in the membrane which is then peeled away with forceps.
In 11 of the 14 eyes, the operation completely closed the macular hole. Of the other three unoperated eyes, the eye with the smallest macular hole spontaneously closed.
Before the operation, the mean Snellen best corrected visual acuity (BCVA) was 20/210, or about 1/10th the normal visual acuity; the range was from 20/30 to 2/200. After the operations, the mean BCVA was 20/62 (range: 20/20 to 4/200). These statistics included all eyes (the 14 operated eyes and the three unoperated ones).
The authors concluded “Full-thickness MH can result from momentary exposure to high-power handheld laser devices. While spontaneous closure may occur in rare cases, most cases require early surgical intervention. Vitrectomy may be successful in closing the macular hole with visual acuity improvement in most of the cases.”
From the abstract of the study by Alsulaiman SM, et al., “Full-Thickness Macular Hole Secondary to High-Power Handheld Blue Laser: Natural History and Management Outcomes” in the American Journal of Ophthalmology, July 2015 Vol. 160, Issue 1, Pages 107-113.e1.
Note: Other studies have been published based on this data, an August 2013 LaserPointerSafety.com story about the first study is here.
It was unclear from news reports whether the warning was sent directly to students at school, or if the warning came only as part of a May 4 2015 news story on the website Health24.com. A May 11 search of the Gauteng Department of Education website did not show any announcements, notices, documents, or other information warning about laser pointer hazards.
The spokesperson said that at least two children had permanent eye damage from lasers. One case cited was a South African 11-year-old boy who looked into the laser light after one of his classmates was playing with it. His mother said “He now has a blind spot right in front of him, but still see the sides of the eye [sic].” This case was reported in April 2015. The other South African case involved a child who aimed a laser’s light into his eye and had permanent damage.
Gautang is the most populous province in South Africa. It contains the cities of Johannesburg, Pretoria, Midrand and Vanderbijlpark.
From Health24.com: Story about the warning to learners, and story about the 11-year-old boy being injured.
It begins by summarizing misuse in sports, and in the thousands of incidents per year in the U.S. where lasers are aimed at aircraft.
The authors, Dr. Gregory D. Lee and Dr. David R. Lally, then write “Perhaps the greatest concerns are raised by reports of unsupervised children who have received these lasers as toys or gifts and expose themselves to the laser beams, causing permanent retinal injury with reduced central vision. From 2000 to 2009, there were five reports of 18 patients with injuries due to laser pointer exposure.”
They discuss the types of injuries (thermal, photochemical and mechanical) and locations of retinal injuries. There is a listing of laser classes, with “pointers” — Class 1, 2 or 3R (IIIa) — being distinguished from similar-looking but more powerful Class 3B and 4 “handheld” lasers.
The authors conclude as follows:
“Inappropriately used class 3B or 4 lasers should be considered weapons that can cause serious, permanent bodily injury. Even brief exposures to diffused rays of laser beams can cause temporary flash blindness that may last for hours in airline pilots, endangering the lives of passengers, particularly during takeoff and landing sequences. Cases of short-range laser exposure are becoming more common, often involving children who are inappropriately given these devices as toys, and these patients are referred to retina specialists after the damage has already occurred.
“No definitive experimental study, case report, or animal model has shown improvement in these injuries with any type of treatment, but typically these patients are treated with a short course of corticosteroids or nonsteroidal antiinflammatory drugs. Secondary choroidal neovascularization has been treated successfully with intravitreal anti-VEGF agents.13,14
“Clinicians, particularly retina specialists, can raise awareness of this rising public health issue by educating patients and parents about the hazards of laser pointers. Legislation is currently being written to impose stronger regulations on the distribution and sale of these devices. If a patient presents with findings of a laser-related retinal injury, clinicians should report the incident to the FDA so that investigations can be performed into the manufacturers of these devices. Reports can be made at www.fda.gov/downloads/AboutFDA/ReportsManualsForms/Forms/UCM236066.pdf.”
From Retina Today
In addition, volunteer Kelli Halston Hoversten suffered two permanent eye injuries during the climactic “Man Burn” in 2014. Her left eye was permanently blinded by a handheld laser, and her right eye was partially blinded by a vehicle-mounted laser. (The injuries significantly affected her. Hoversten “lost her job as an arborist because they can’t insure her now” and she no longer rock climbs or ice climbs recreationally due to the loss of depth perception. She is allowed to drive but “just barely” since her central vision is blocked.)
According to an article about the policy change in the Reno Gazette-Journal, Hoversten will attend the 2015 Burning Man event, in part because of the new laser policy.
The Burning Man ban on handheld lasers applies even to low-powered laser pointers less than 5 mW in power. In a separate blog post comment, Burning Man press official Will Chase wrote: “Because of the difficulty in discerning the difference between dangerous and non-dangerous handheld lasers — and because you don’t want to be wrong — it’s been decided to prohibit all handheld lasers.”
The new webpage with the laser policy also noted that the restriction on handheld lasers “is in line with nearly all major festivals and events in the United States and Europe.”
Non-handheld lasers are still allowed at Burning Man if they are on art installations, “DMV Mutant Vehicles,” or are in theme camps. Such lasers must be disclosed on the art, vehicle or camp application. An Event Safety Officer will review the applications; only safe uses will be allowed.
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Commentary from LaserPointerSafety.com: There have been many pilot claims of eye injuries caused by laser pointers aimed at their aircraft. FAA has investigated some of the most serious claims. In 2011, a person knowledgeable about these studies told LaserPointerSafety (on background): “I haven't seen anything that convinces me that any of the FAA incidents are true injury. I haven't seen any convincing evidence of delayed laser lesion effects. I do know that headaches and eye pain and photophobia and light sensitivity have been reported and associated with laser illumination. I have seen nothing convincing me that there is real cellular, tissue injury.”
There have been a few cases (<10?) of temporary eye injury, where the eye healed. This is similar to how skin can heal after a sunburn. In all of these cases, the pilots returned to flying.
There have also been cases of reported laser injury to the cornea. This is the transparent surface of the eye. Visible laser light passes right through and is not absorbed. The cause of these reported “laser” injuries is the pilot rubbing his or her eyes too vigorously, causing painful scratches in the sensitive cornea. Any damage from a visible laser beam would be on the light-absorbing retina.
Note that FAA limited its statement to commercial pilots. There may be military pilots in conflict zones who have been injured by laser weapons. If so, this information would be classified. Due to the seeming lack of urgency with FAA and U.S. military, any such injuries would not seem to be a threat to commercial pilots in the U.S.
Here are lists of all LaserPointerSafety.com news items tagged with the keyword “eye effect or injury”: aviation injury incidents, non-aviation injury incidents, other eye injury stories.
LaserPointerSafety welcomes any documented cases of pilot eye injuries. Contact us with the links etc., and also contact FAA so they can be aware of the cases.
Eibhlin McLoone, a consultant ophthalmologist with the Belfast HSC Trust, has treated several of the children and said the devices "are not toys".
"Sadly, I have seen children who have eye damage because they have played with a laser pointer and unfortunately once the eye has been damaged by a laser pen the damage is irreversible," she said.
"Due to the risk of permanent visual impairment, it is vital that the public is aware of the risks associated with laser pointers and that these devices are never viewed as toys."
Ms McLoone added: "Unfortunately, once the laser burn has happened there is no treatment available to reverse it."
From the Belfast Telegraph
The October 7 2014 story was a follow-up to an incident at an NFL football game on October 5, when Buffalo Bills players complained of lasers being aimed at them during a game with the Detroit Lions. The NFL and police were said to be investigating.
USA Today’s Martin Rogers wrote that Dr. Robert Josephberg “has lobbied members of Congress for more than a year to discuss criminalizing intentionally dangerous use of laser pointers, to no avail. Josephberg told the newspaper that intentional shining of a laser at someone should be a felony: “There has been a significant increase in medical journals of reports of blindness caused by the lasers. The use seems to be increasing – and so does the power and availability of the pointers. Congress needs to take note.”
In a February 28 2011 story in the New York Times, Josephberg recounted how he saw a high-school student who had a blind spot from a 50 milliwatt green laser pointer. At first he did not believe that lasers were available that could cause such an injury. But he bought a 100 milliwatt laser for $28 online; Times writer Christine Negroni said “he could hardly believe how easy it was.”
A June 2011 article in the magazine of Westchester (NY) Medical Center, where Josephberg works, quoted the doctor as saying “I contacted new Republican Congresswoman Nan Hayworth of the 19th Congressional District, who is an ophthalmologist herself. We are working with her, trying to write a bill that addresses this problem.”
From USA Today, the New York Times and ”Health & Life” magazine from Westchester Medical Center
The first draft of the April 2014 law called for a Class Five felony to “knowingly or intentionally” aim a laser towards an aircraft. But there was concern among legislators that juveniles could end up with a felony record. The bill passed once the penalty was reduced to a Class One misdemeanor.
In a September 22 2014 story, reporter Emilie Eaton recounted Arizona’s experience. FAA-reported incidents in the state rose from 138 in 2010, to 202 in 2013. One police pilot interviewed said that he had been hit by lasers over 100 times, during a 22 year career. The pilot, Chris Potter, said he had permanent damage from a laser strike: “It literally felt like I got punched in my eye and there was a piece of debris, like a piece of glass in my eye.”
Another pilot quoted, Pima County Sheriff’s Department deputy Chris Janes, said he has has between 12 and 24 laser strikes from 2007 to 2014: “I have not received any eye damage. But I’ve had headaches afterward. I’ve had eye discomfort for several days afterward.”
From Cronkite News, via the Tucson Sentinel
TASC is working on countermeasures such as laser eye protection and the development of procedures for injury assessment. The work is being performed under the Optical Radiation Bioeffects and Safety contract with the Air Force’s 711th Human Performance Wing’s Optical Radiation Bioeffects Branch at Fort Sam Houston in San Antonio, Texas.
From the San Antonio Business Journal
After tests in mid-2013, the Basil Justice and Security Department purchased 1,000 pairs of laser protective eyewear, at 200 Swiss Francs each (USD $224).
All Basel police officers and rescue emergency vehicles are equipped with the glasses, as of December 2013. Other Swiss cantons are in the testing phase.
The Basel anti-laser glasses are demonstrated in this frame from a SRF video.
From a December 16 2013 report by Schweizer Radio und Fernsehen, (original German text and Google-translated into English). Thanks to Basel officer Ruedi Maier for bringing this to our attention. For additional news items from Switzerland, including the 2011 purchase of laser protective eyewear for air rescue helicopter pilots, click here.
A video showing the “AirTerminators Super Combat Helicopters” in January 2014 at the London Toy Fair shows an operator getting a brief laser hit just below his eye. The laser is said to be Class 1; if so, such a brief exposure would not be considered harmful according to safety guidelines.
However, it is not recommended for children to play with lasers. Further, it is unknown if the laser remains operational even if the helicopter is stationary or is handheld instead of free flying.
The helicopter is in the middle top of the photo. A red line can be seen just under the operator’s eye. This is the path of the laser from an opposing helicopter as it went across his face during the video frame. This can be seen at 34 seconds into a YouTube video of the demonstration.
Hawks were originally used to scare pigeons away from the modern building, opened in 2004. When these proved unsuccessful, contractors turned to the laser pens. They are primarily used at dawn and dusk to disturb and disperse roosting pigeons.
A spokesperson for the Pigeon Control Advisory Service said “Laser pens can be lethal and blind animals and birds. They are definitely not something we would ever recommend.” PETA, People for the Ethical Treatment of Animals, also said the animals eyes could be damaged and that other humane, non-harmful methods should be used.
From the Edinburgh News, Jan. 23 2014. Thanks to Paul Bluesky for bringing this to our attention.
UPDATED Jan. 27 2014: The contractors said they must abandon the “no kill” policy in order to further reduce the pigeon population on the Scottish Parliament building. A Parliament spokesperson said there had been no change of policy. From the Edinburgh News
The Tucson Police Department had about 50 lasing incidents in 2013; the perpetrator was caught in most of the cases. But there was little prosecution.
Orr says the bill is needed because “there’s really no punishment. The county prosecutor, because it's not at a felony status, doesn't go after them. And so literally, you get a ticket and nothing happens. But you're endangering lives."
Orr is working with Tucson police pilot Chris Potter, who says he has been hit by a laser pointer about 100 times in his career. Potter says a laser pointer permanently damaged his right eye around 2011.
According to News 4 Tucson, “the FBI will launch a public awareness campaign about the issue next month.” It was not clear if this was an Arizona-area initiative or nationwide.
From News 4 Tucson
UPDATED - February 4 2014: The Arizona House Judiciary Committee voted in favor of increasing the penalty for persons who point lasers at aircraft. HB 2164 would make it a Class 5 felony, with a presumptive sentence of 18 months in prison, to knowingly or intentionally point a laser at an occupied aircraft. And the penalty would go to 30 months if the act disables the pilot or causes serious physical injury to anyone on board. The legislator who introduced the bill, Ethan Orr, is considering reducing the penalty slightly, to a Class 6 felony, when it goes to the full House. Prosecutors could reduce the charge from a felony to a misdemeanor when appropriate. Orr said this might be the case for youths so that a single mistake would not result in a felony record. From KWST.com. A related article at AZCentral.com includes comments from LaserPointerSafety.com’s Patrick Murphy on the issue.
UPDATE 2 - May 1 2014: The bill was eventually amended to make the act of aiming at an aircraft a Class 1 misdemeanor. The act became an assault if the pilot was unable to safely operate the aircraft or if anyone onboard suffered a serious physical injury. The amended version passed both legislative bodies and was sent to Governor Jan Brewer, who signed it on April 30 2014. From the Arizona State Legislature legislative history of HB2164.
UPDATE 3 - September 23 2014: The Arizona Police Association and other law enforcement groups want to increase the penalty to a felony. They hope to introduce a measure when the legislature re-convenes in January 2015.
The regulations were based in part on public submissions made in response to a November 2012 Ministry of Health proposal. Submissions were received from organisations including retailers, government agencies, non-government organisations, professional associations, importers, the aviation industry, members of the public and other organisations with an interest in high-power laser pointers. Their suggestions were compiled in a 20-page document which helped guide the new regulations.
"High-power laser pointers can cause eye injuries, even blindness, and skin burns. ACC accepts around 10 claims a year for these injuries," says Mrs Goodhew.
"They can also cause temporary flash blindness, which poses a serious risk if the person affected is a pilot or in charge of a vehicle or equipment. The Civil Aviation Authority reports around 100 laser strike incidents on planes each year.”
The new controls, under Health and Customs legislation, cover the import, supply and acquisition of high-power laser pointers. They do not currently restrict the possession of high-power laser pointers. A bill is before Parliament which, if passed, would make it illegal to be in a public place with a laser pointer without a reasonable excuse.”
"The new controls have been crafted to only target the high risk hand-held laser pointers with a power output of greater than 1 milliwatt,” Goodhew said. “The regulations are in line with Australia’s restrictions and recommendations by the World Health Organization.”
Click to read more...
“The purpose of this study was to investigate what dose of laser radiation, in terms of intensity and exposure time, may be associated with eye damages. The study has been limited to unwanted exposures of laser radiation from commercially available laser pointers. Of particular interest has been to search for data that clarify the dose-response relationships for functional disabilities that persist more than 6 months.”
“The study shows that long-term vision loss can occur as a result of involuntary exposure from commercially available (strong) laser pointers at close range. The injury may occur before a normal person is able to respond by closing the eyelid, although there are only a few cases reported. A minor such damage is transient within a few days. It is also likely that such a visible injury to the retina becomes functional, i.e. prevents reading skills. What dosage is required for the disability to become permanent is not clear in the literature. Also, the dynamics of evolvement and repair of tissue damages and disabilities are hardly described at all.”
Author: Stefan Löfgren, Jörgen Thaung and Cesar Lopes
Publisher: Strål Säkerhets Myndigheten (SSM - Swedish Radiation Safety Authority)
Publication date: 19 November 2013
No of pages: 50
Price per publication: 100 SEK (incl. VAT)
Download: 2013:30 Laser pointers and Eye injuries - An analysis of reported cases [1385 kb]
A summary by LaserPointerSafety.com of the study’s objectives, major findings, and conclusion is here.
UPDATED January 2016: The SSM released an update, with 47 additional cases worldwide of eye injuries from consumer lasers. A summary by LaserPointerSafety.com is here; the full SSM document is here.
The statement came as hundreds of Arizona law enforcement pilots attended a safety seminar in Tucson focusing on laser beam incidents. In 2012 in Tucson alone, the police department’s air unit had “close to 50 incidents”, according to Potter. As of November 2013, Phoenix was the top U.S. city for laser incidents.
From KVOA News
According to HealthNewsDigest.com, “All injuries occurred during play and involved teenage boys and young males, between the ages of 11 and 30. Some injuries were accidental, but others involved a playmate intentionally pointing the laser beam at the victim's eye. The distance between the victim's eye and the laser beam ranged from 1.7 feet to 20 feet (a half-meter to 6 meters). Those who suffered retinal holes were injured at the closest distance, around half meter, or 1.7 feet. Generally, injury from greater distance resulted in less serious damage, the authors of the report say.”
The report was presented August 24 2013 during a Toronto meeting of the American Society of Retina Specialists by Fernando Arevalo, M.D. He is professor of ophthalmology at the Wilmer Eye Institute, Johns Hopkins School of Medicine, in Baltimore Maryland and is also affiliated with the Saudi hospital. Dr. Arevalo hopes that his findings, which were provided to the Minister of Health, will result in changes to how Saudi Arabia regulates handheld lasers.
Click to read more...
In an August 6 2013 press release and Consumer Health Information article, FDA warned parents that lasers operated unsafely can cause serious eye injuries and even blindness. FDA said injuries from lasers can go unnoticed for days or weeks since there is no pain. But vision can slowly deteriorate over time, eventually causing permanent eye damage.
FDA gave the following as examples of children’s toy laser products:
- Lasers mounted on toy guns that can be used for “aiming”;
• Spinning tops that project laser beams while they spin;
• Hand held lasers used during play as “light sabers”;
• Dancing laser beams projected from a stationary column; and
• Lasers intended for entertainment that create optical effects in an open room.
Interestingly, the FDA’s press release and article gave tips on safe usage, including not aiming at car drivers or sports players -- but did not say that it is unsafe and illegal to aim at aircraft.
On August 7 2013, FDA issued draft guidance for industry on minimizing the risk of lasers in children’s toys. Comments are invited within 90 days of the Federal Register publication of the guidance, or by November 4 2013. The draft guidance is reprinted below.
Click to read more...
The laser injury claim rate has increased from about 5 per year to about 13 per year, over the 2000-to-2013 period. The increase works out to 0.73 additional claim per year. This increase is one reason that New Zealand is taking action in 2013 to restrict higher-power handheld lasers.
Click to read more...
Because the laser pulse wavelength used was in the infrared, and the cells were cultured (not live retinas) there is no current practical use for pilots and others looking for glasses-free resistance to visible laser light. However, this research may open up other avenues as it does indicate that perhaps the retina can be “hardened.”
Click to read more...
The new law will not cover low-power lasers below 1 milliwatt which are used for presentations, surveying or gun sights. It will control importation, and will restrict use of higher-power handhelds to “authorized users who have a legitimate purpose such as astronomers, researchers and the NZ Defence Force”, according to an Associate Health Minister.
Click to read more...
The study found that helicopters were 3.4 times as likely to be illuminated at altitudes below 2,000 feet than fixed-wing aircraft. Helicopter aircrews were twice as likely to report adverse effects such as distraction, vision interference, operational problems, and pain.
The study also broke down adverse effects by the type of flight, such as commercial, law enforcement, medical and military.
One conclusion of the study is that the “results may also justify the expense of equipping rotary-wing aircraft (particularly law enforcement aircraft) with laser detection and tracking devices to improve the possibility of apprehending perpetrators of these offenses.”
A detailed summary is at LaserPointerSafety.com’s 2013 FAA helicopter study webpage. The full 6-page report is available online from the FAA.
The Yahoo Sports story noted that laser pens are often misused by European soccer fans. In late February 2013, two world-famous players, Cristiano Ronaldo and Lionel Messi, were targeted during a pair of games.
Ronaldo (left) and Messi, illuminated by lasers during matches between Real Madrid and Barcelona
Josephburg told Yahoo Sports that athletes could be especially at risk, since lasers could cause serious damage from an exposure of a few seconds. He said “If I was a ball player I would be terrified. I only hope that Congress acts on this before some real harm is done.”
Lasers with powers of over 50 milliwatts are dangerous, Josephburg said, and can have serious effects almost immediately. The only effective deterrent is to punish possession or use of high-powered pointers, according to Josephburg: “There is simply no need for a regular person to have one of these.”
From Yahoo Sports
From Vertical magazine
Click to read more...
The agency states that battery-powered pointers and handhelds “manufactured, advertised, sold, imported or leased should be limited to … Class 3R” which is less than 5 mW visible output. It is unclear whether “should” is advisory or is a regulatory requirement.
The document focuses on eye, skin and fire hazards of lasers and does not discuss the problem of visual interference with pilots’ or drivers’ vision while operating vehicles.
From Newswire. The 2012 Health Canada press release is below (after the Read More… link). The July 2011 press release is here.
Click to read more...
The ALESA card is available in hard copy, and can also be downloaded from CAA’s website. If downloaded, the Amsler Grid on the first page should be printed so it is 10 x 10 cm.
When staring at the dot in the center of the grid, if the lines appear distorted or there are blank or faded areas, there may be a problem. The person is encouraged to remove themselves from aviation-related duties such as flying or air traffic control, and to see an eye specialist.
The second page has a flowchart of exposure conditions leading either to a “1” meaning unlikely eye damage or a “2” meaning eye damage possibility. If the person scores a “2”, the flowchart suggests they see an eye specialist.
From PilotWeb and the CAA ALESA webpage. The CAA press release about ALESA is here.
[NOTE: The amounts above represent about $2,400 per pair of laser protection spectacles. More information about anti-laser glasses for pilots, including non-military versions protecting against one or two visible wavelengths for roughly $100-200, is here.]
From a Teledyne Technologies press release
The answer first noted that laser weapons are large. An anti-missile laser required a Boeing 747, the Navy set fire to a boat with a destroyer-mounted laser, and a dazzler-type laser called the PHaSR is as portable “as a bag of cement.”
Then, Straight Dope purchased a 1 watt blue handheld laser (the same or similar to the Wicked Lasers Spyder III Arctic). They aimed it at room temperature pork chops and bacon. From one foot away, it took 27 seconds of continuous exposure before smoke appeared. Even with matches, it took 11 seconds to light a match from one foot away, and 15 seconds from 32 feet away.
The January 6 2012 column concluded that handheld laser ray guns are not practical: “…the likelihood that this laser would actually change somebody’s mind (other than via intimidation alone) is virtually nil…. no bad guy is going to sit still while you fry him.”
Story and photos are at the Straight Dope website. The column was also printed in the Washington City Paper.
UPDATE: In comments at the Washington City Paper, “dave b” noted that exposure to skin isn’t necessarily the important factor: “The key is to get the laser into someone’s eye.”
Concept of the rifle, from the Daily Mail
The developer is Photonic Security Systems, which also markets the rifle as a pirate deterrent. The Telegraph says that similar devices have been used in Afghanistan by NATO-led International Security Assistance Force troops.
PSS managing director Paul Kerr told the International Business Times "The very purpose of this technology is to be non-damaging … If someone is prepared to just stand there and stare down the barrel at this, which would be incredibly uncomfortable, then they are definitely a threat.” He said that he has often been exposed to the laser: "The quality and safety of the device is paramount and I know that first hand because I have been the guinea pig many times. I know what it is like and I know how effective it can be."
Author and activist Cory Doctorow points out that “the UK is a signatory on the Protocol on Blinding Laser Weapons … this weapon wouldn’t run afoul of international law if it (merely) reduced your vision to the point where you were impaired but not legally blind, permanently.” Doctorow also says “Twitter wags are already predicting a resurgence of mirrorshades [reflective sunglasses] among protesters.”
From the Telegraph, the Daily Mail, the International Business Times and BoingBoing. See related story on BAE Systems anti-pirate dazzler.
Speakers generally agreed on the nature and scope of lasers as a threat to air safety. They also offered similar solutions, including educating the public to not misuse lasers, prosecuting those who do, training pilots on how to "recognize and recover" from incidents, increasing the number of reports from pilots and the public, and restricting laser pointer availability.
The ALPA conference made news primarily for the announcement of a new FAA web page, which can be reached via www.faa.gov/go/laserinfo. FAA Administrator Randy Babbitt told the ALPA attendees that the web page -- erroneously described as a "website" in many media accounts -- would centralize the agency's information on laser/aviation safety. The page includes email addresses where pilots, air traffic control and the public can report laser incidents (see separate story about the FAA web page).
Babbitt also said that the FAA currently has filed 18 civil cases against individuals who aimed lasers at aircraft. There is a maximum $11,000 fine in each case.
Other speakers gave updates and information in their areas of expertise.Click to read more...
The action was taken because laser attacks are on the rise: six in 2009, 11 in 2010 and 16 to mid-October in 2011.
The sale of strong laser pointers was banned in Switzerland in May. The Federal Health Office is currently reviewing the possibility of banning their possession and use. Checks carried out by the Federal Office of Metrology this year showed that more than 95 per cent of the pointers tested were stronger than the permitted limit.
LIA did not give specific recommendations to avoid eye injuries, other than individuals being cautious. They did note that “[t]here is an active debate about what should be done. Is the solution education, regulation or prohibition for this type of hand-held laser device?…. Until the time that these lasers are statutorily banned, regulated through licensing or are widely recognized as a hazard, many more injuries will occur. The public should take note of these dangers immediately and keep these high-power, hand-held devices away from children and the untrained user.”
Full text of the July 26 2011 press release from LIA News is below (click the “Read More…” link).Click to read more...
They caution that laser pointers should be limited to IEC Class 3R (less than 5 milliwatts for visible beams). Health Canada says that higher powered Class 3B and 4 lasers “should not be used as laser pointers or in any other application unless operated by individuals who have been professionally trained in laser safety.”
The full text of the press release, including instructions on how to report suspected laser injuries, is available by clicking the “read more” link below.
From MarketwireClick to read more...
The article listed four injuries to youths. In three of the incidents, a young person deliberately stared into a laser beam, while the fourth was caused by a high-schooler whose friend waved a 50 mW laser in his face. (Besides these anecdotal accounts, the article gave no overall statistics on injuries except to say that an ophthalmologist association is “unaware of any increase in eye injuries caused by lasers.”)
Author Christine Negroni covered a number of topics, including:
- There has been “ninefold increase over five years” in laser illuminations of aircraft
- Eye doctors are “shocked” that high-powered lasers are available on the Internet with no purchase restrictions.
- A U.K. physician says the U.S. limit should be 1 mW, that even at 5 mW laser pointers have “acute” dangers.
- FDA says that noncompliant (“illegal”) lasers are available despite agency seizures.
- Wicked Lasers says that its products are compliant, that they are “extremely clear” about eye and fire hazards on their webpages, and that they will be offering online safety lessons “before checkout”.
- A “large community” of laser enthusiasts wants to keep lasers available.
- An 18-year-old laser hobbyist, who wears goggles and is supervised by his parents, said he was learning about electronics, soldering, physics, light, optics and mechanics.
From the New York Times, online on Feb. 28 2011, in print on March 1 2011 on page D5 of the National edition.
This is said to be the most serious Norwegian case of laser pointer eye damage. There are about 12 known cases although authorities fear there may be more actual cases.
From the Icelandic Radiation Safety Authority. For the original machine-translated version, click the “Read More…” link below. A Norwegian TV report on the case is here.Click to read more...
More than two weeks after the accident, he reports “... there are no identifiable irregularities. I am certain there is permanent damage in the spot, but it is so far out in [my] peripheral vision, that it is just not noticeable. So I have officially ceased worrying about it. Lesson learned.”Click to read more...
The NIST team came up with a simple “home test” so that interested persons can test their own laser pointers. The test requires a digital or cellphone camera, a compact disc used to spread out the wavelengths, a webcam to view infrared light, and an infrared TV remote control.
At top, light from a green laser pointer is diffracted (spread out) by a compact disc and viewed with a digital camera that can see only visible light. At bottom, a webcam with no infrared-blocking filter shows this laser also emits infrared laser light (white dots). For this unit, the invisible infrared light is more powerful than the visible green light. (NIST photo)
The unwanted and potentially hazardous infrared light is due to misaligned or missing filters in laser pointers that use infrared to generate visible green light. Low-cost pointers are at special risk, due to cutting corners in design, materials or manufacture to reduce costs.
The team warns that, whether or not a laser pointer emits dangerous levels of infrared, users should “never point the lasers at the eyes or aim them at surfaces such as windows which can reflect infrared light [as well as visible light] back to the user” or others in the area.
For more information:
- NIST press release summarizing the issue
- NIST technical note A Green Laser Pointer Hazard which includes instructions on how to test to see if a green laser pointer has unwanted or excess infrared light emission (PDF format)
UPDATE - March 2011: A laser expert has privately warned LaserPointerSafety.com that the CD technique requires caution. This is because when the laser light is diffracted, the infrared light is no longer co-linear (same path) as the visible light. Therefore, the viewer cannot know exactly where the IR light is going unless they are looking through an IR-sensitive camera or webcam.
Perpetrators are shining beams onto the faces, “chests and private parts” of passers-by; the latter starting fights with boyfriends according to the chief. One family complained that their child had a seizure after a laser was shone on their eyes. A councilwoman said “a young boy ... shined a green laser directly into her eyes. She said her vision is now hazy and impaired, though a doctor advises her it will eventually return to normal.”
An article from delmarvanow.com quoted 29-year-old Richard Drake of Ocean City, who in 2009 “sustained serious damage to his left eye after having a red laser shone purposefully in the face. Now he sees everything with a pinkish hue.” He is campaigning to have laser pointer sales banned in the resort town.
The town council was poised to ban sales to minors and possession by minors, to make it illegal to aim lasers at people and vehicles, and mandating signs in stores and handouts to buyers that describe the city’s ordinances. (The legislation passed; see story here.)Click to read more...