DOT/FAA/AM-01/7

Van B. Nakagawara

Ronald W. Montgomery

Civil Aeromedical Institute

Federal Aviation Administration

Oklahoma City, Oklahoma 73125

April 2001

Final Report

This document is available to the public

through the National Technical Information

Service, Springfield, Virginia 22161.

Laser Pointers:

Their Potential Affects on

Vision and Aviation Safety Office of Aviation Medicine

Washington, D.C. 20591

U.S. Department

of Transportation

Federal Aviation

Administration
NOTICE

This document is disseminated under the sponsorship of

the U.S. Department of Transportation in the interest of

information exchange. The United States Government

assumes no liability for the contents thereof.
i

Technical Report Documentation Page

1. Report No. 2. Government Accession No. 3. Recipient's Catalcog No.

DOT/FAA/AM-01/7

4. Title and Subtitle 5. Report Date

Laser Pointers: Their Potential Affects on Vision and Aviation Safety April 2001

6. Performing Organization Code

7. Author(s) 8. Performing Organization Report No.

Nakagawara, V.B., Montgomery, R.W.

9. Performing Organization Name and Address 10. Work Unit No. (TRAIS)

FAA Civil Aeromedical Institute

P.O. Box 25082

Oklahoma City, OK 73125 11. Contract or Grant No.

12. Sponsoring Agency name and Address 13. Type of Report and Period Covered

Office of Aviation Medicine

Federal Aviation Administration

800 Independence Ave., S.W.

Washington, DC 20591 14. Sponsoring Agency Code

15. Supplemental Notes

This work was performed under task AM-B-00-TOX-203

16. Abstract

INTRODUCTION. Laser pointers have been used for years to highlight key areas on charts and screens

during visual presentations. When used in a responsible manner, laser pointers are not considered hazardous.

While momentary ocular exposure to the light emitted by these devices can be startling to the observer and

may result in temporary visual impairment, such exposures are too brief to cause any permanent ocular injury.

However, as the availability of laser pointers has increased, so have reports of their misuse by some children

and adults. In recent years, both the Food and Drug Administration and the American Academy of

Ophthalmology have issued warnings concerning the possibility of eye injury from handheld laser pointers

and recommended keeping these devices away from children. The purpose of this report was to investigate the

illumination of aircraft by laser pointers in the National Airspace System. CASE REPORTS. From January

1996 to July 1999, the FAA’s Western-Pacific Region identified more than 150 incidents in which low-flying

aircraft were illuminated by lasers. Laser pointers were used in the majority of these incidents, and there were

several occurrences of visual impairment to the pilot. Representative examples of documented reports are

presented that involved the illumination of civilian flight crewmembers by these hand-held devices.

CONCLUSIONS. Laser pointers have caused ocular injury and may compromise aviation safety when used

to illuminate aircraft in critical phases of flight. The physiological effects of exposure to laser light and the

regulation and classification of commercial laser products are discussed. The proper selection and use of these

devices can minimize the threat of temporary incapacitation and eye injury.

17. Key Words 18. Distribution Statement

Aviation, Vision, Laser, Aircraft Incident, Aircraft Document is available to the public through

the National Technical Information Service

Springfield, VA 22161

19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price

Unclassified Unclassified 10

Form DOT F 1700.7 (8-72) Reproduction of completed page authorized

1

LASER POINTERS: THEIR POTENTIAL AFFECTS ON VISION AND AVIATION SAFETY

INTRODUCTION

Teachers and lecturers have used laser pointers

for years to highlight key areas on charts and screens

during visual presentations. When used in a responsible manner, laser pointers are not considered

to be hazardous (see Figure 1). However, as the

availability of such devices has increased so have

reports of their misuse. As a result, the Food and

Drug Administration (FDA) issued a warning in

December 1997 on the possibility of eye injury to

children from handheld laser pointers (1). Of particular concern was the promotion of laser products

as children’s toys, such as those that can project

cartoon figures and other images. In the wake of

two reports of eye injuries involving young children

caused by laser pointers, the American Academy of

Ophthalmology (October 1998) upgraded an earlier caution to a warning, stating that laser pointers

can be hazardous and should be kept away from

children (2).

There have been other disturbing reports involving the misuse of laser pointers (3,4). Some of these

include: arrests made by police after a red beam was

interpreted to be that of a laser-sighted weapon,

spectators aiming laser pointers at athletes during

sporting events, the illumination of drivers on

highways, and numerous incidents involving the

illumination of fixed-wing aircraft, and law enforcement and medical evacuation helicopters. The

visible range of a laser pointer can vary considerably

depending on its wavelength, output power, and

environmental factors such as background illumination and air quality. The misuse of laser pointers

involving exposure distances greater than 10 feet is

not likely to cause permanent eye injury. However,

at very close range, the light energy that laser

pointers can deliver into the eye may be more

damaging than staring directly into the sun. This

is due to the refractive properties of the cornea and

crystalline lens, which increases irradiance (W/

cm2

) to the retina by 105. An irradiance of 1 W/cm2

at the cornea would have an irradiance of 10 kW/

cm2

 at the retina (5).

Figure 1: Commercially available laser pointers come

in different styles.

A classmate exposed an 11-year-old girl to a laser

pointer to determine whether the light beam would

cause her pupil to constrict. After staring into the

beam for several seconds and more than once, the

girl immediately noticed her vision was impaired in

her right eye. An initial medical examination found

her best-corrected visual acuity to be 20/60-2 OD,

and an Amsler Grid test revealed a 2° central scotoma. After 11 months, the girl’s best-corrected

visual acuity gradually improved to 20/25+1 OD,

the central scotoma resolved, and only mild irregular pigmentation was evident at the site of the

injury (6).

Momentary exposure from a laser pointer can

cause discomfort and temporary visual impairment

(glare, flashblindness, and afterimages), without

causing permanent physical damage. Glare is the

dazzling sensation induced by a relatively bright

light, which produces unpleasantness, discomfort,

or interferes with optimal vision (7). A typical

example of a glare-producing stimulus would be an

oncoming automobile’s headlights at night. The

visual effects of glare usually cease once the stimulus is removed. However, residual effects, such as

spatial disorientation or loss of situation awareness,

can persist. Flashblindness is defined as visual loss

during and following exposure to a light flash of

extremely high intensity (7). An example is the
2

temporary loss or severe reduction of vision experienced after exposure to a camera flashbulb. This

type of visual impairment may last for several

seconds to a few minutes. Afterimage is a persisting

sensation or image perceived after the correlated

physical stimulus has been removed. Visually, an

afterimage may be the continued perception of the

essential form, motion, brilliance, or color qualities

of the removed stimulus (7). Although temporary,

visual impairment and its associated residual effects can be hazardous if the exposed person is

engaged in a vision-critical activity, such as driving

a car or flying an aircraft.

As a result of a growing number of ground-based

laser illumination of aircraft, several of which resulted in vision impairment to flight crewmembers,

the Federal Aviation Administration (FAA) revised

FAA Order 7400.2D (Procedures for Handling

Airspace Matters; Part 8, Miscellaneous Procedures; Chapter 34, Outdoor Laser Demonstrations), which regulates outdoor laser operations in

the National Airspace System (NAS). This guidance protects the critical airspace around airports

and other sensitive air traffic corridors. In addition,

guidance material is currently being developed to

protect international airspace against the adverse

effects of laser activity on flight operations through

a collborative effort with the International Civil

Aviation Organization (ICAO) Laser Emitters and

Flight Safety Study Group. This report reviews the

incidents of laser pointer illumination of aircraft in

the NAS.

CASE REPORTS

A survey of the FAA’s Western-Pacific Region

found 150-plus laser illumination incidents of

low-flying aircraft for the period, January 1996 to

July 1999. Many of the reported incidents involved

laser pointer illuminations of civilian transport,

medical evacuation, law-enforcement, military, and

private aircraft (8). Several incidents resulted in

visual impairment (glare, flashblindness) of illuminated crewmembers. The survey suggests that helicopters are the most vulnerable to threat of laser

pointer illumination, due to their relatively slow

movement and low-altitude flight.

The following are documented reports that describe typical examples of the rapidly growing list

of aviation incidents involving laser pointers.

• In August 1996, a police helicopter in Seminole County, FL, was illuminated by a red spot of

light the size of a basketball, leading the pilot to

believe a laser-sighted weapon was aimed at the

aircraft. It was determined that the perpetrators

were two local individuals shining a laser pointer

into the trees, not realizing the light beam could

reach the helicopter (9).

• In June 1998, in San Panqual Canyon, CA, an

individual leaving a party used a red laser pointer to

illuminate a San Diego police helicopter while it was

flying at 600 feet above ground level (AGL). The

pilot’s temporary loss of visual reference was made

even more dangerous due to the canyon setting. The

suspect was arrested after the incident (10).

• In June 2000, a 15-year-old boy was booked

into the Youth Service Center, Seattle, WA, for

first-degree unlawful discharge of a laser, a felony,

after reportedly flashing a laser beam at the King

County Sheriff’s helicopter, Guardian One. Shortly

after 11 p.m., Guardian One was about 1,200 feet

AGL just east of Renton when the laser illuminated

the helicopter. The crew was able to direct ground

units to the home where the beam originated. The

teenager was arrested and two laser pointers were

confiscated. This episode was the third in two

weeks in which a laser disrupted the helicopter

crew in flight (11).

DISCUSSION

While there is little or no risk of biological

damage resulting from momentary exposure to

laser pointers, misuse of these devices can and has

resulted in ocular injury (12). Such injuries from

laser pointers are usually the result of prolonged

self-exposure or malicious illumination by another

individual. Visible and near-infrared wavelengths

(400-1400 nm) are focused by the cornea and lens

and absorbed by the retina (see Figure 2). Injury

occurs when the energy level and duration of a laser

exposure are sufficient to damage the eye’s retina.

Since the power output of laser pointers is relatively

low (< 5 milliwatts), an exposure that could cause

injury must be from close range (10 feet or less) and
3

be several seconds to a few minutes in duration.

Retinal injury can result from a delayed photochemical reaction or acute thermal damage caused

by the absorption of laser energy in the retinal

tissue. While these injuries can sometimes result in

permanent visual impairment, exposure from a

laser pointer is not likely to cause biological damage to aircraft pilots due to atmospheric attenuation, extended distance, and low power output.

When selecting a laser pointer, the consumer

should be familiar with the different product labels. The FDA’s Center for Devices and Radiological Health (CDRH) regulates the manufacture of

commercial laser products. Manufacturers are required to classify laser products as Class I, II, IIIA,

IIIB, or IV; certify by means of product labels; and

submit a report demonstrating that requirements

of compliance standards are met (13). Laser classification is based upon the potential of a beam to

cause biological damage from unintentional viewing. The maximum permissible exposure (MPE)

for visible, continuous-wave lasers is 2.5 milliwatts

per centimeter squared (mW/cm2

) for a 0.25 sec.

exposure (13). Table 1 provides a summary of the

different classes of visible lasers, including their

maximum output power (expressed in mW) and

the FDA-required information that can be found

on the product label.

Class I lasers are not considered hazardous and

require no special labeling. Eye injury from unintentional exposure to Class II and Class IIIA lasers

would be prevented by the natural blink response

(i.e., < 0.25 seconds). However, Class IIIA laser

pointers can cause permanent injury from prolonged viewing (12) or when viewed through optical instruments, such as binoculars or telescopes. A

DANGER logo is required on all Class IIIA lasers

manufactured as pointers if the MPE is exceeded

during brief exposures of less than 0.25 seconds

(13). (Note: The American National Standards for

Safe Use of Lasers [ANSI Z136.1] recommends

laser safety training and area warning signs for all

Class IIIA lasers that carry the DANGER logo.)

Although not manufactured for use as “legal” laser

pointers, some Class IIIB devices can cause eye

injury if the beam is momentarily viewed, either

Retina

Optic Nerve

Cornea

Lens

Visible and NearInfrared Beams

Figure 2: Visible and near infrared beams are focused by the cornea and lens onto the retina.
4

directly or off a reflective surface. (Note: There

have been reports of Class IIIB laser pointers imported for sale via the Internet (14).)

The color of a laser beam is directly related to its

wavelength. If two laser pointers are of equal power

but different wavelengths, one may appear brighter

than the other. This is due to the human eye’s

inherent sensitivity to some wavelengths (see Figure 3). Most laser pointers are red or red-orange in

color, with wavelengths ranging from 630 to 680

nanometers (nm). The 650-nm wavelength pointer

is often selected because of its relatively low cost

and increased brightness, about 2 times that of the

670-nm laser pointer. The 635-nm pointer is

generally more expensive, but is very bright (approximately 10 times the brightness of the 670-nm

pointer) and is useful for outdoors or in environments where there is excessive ambient light (15).

Green laser pointers are relatively new devices

that emit a 532-nm beam of light. This wavelength

is near the eye’s peak sensitivity, resulting in exceptional visibility and brilliance. The human eye

perceives a 532-nm beam to be about 35 times

brighter than an equivalent powered 670-nm laser

beam (15). A green laser pointer is considerably

more expensive than a red laser pointer, since the

green laser diode costs much more than standard

red laser diodes. In addition, the high electrical

current required by the green diodes rapidly depletes battery power making them more costly to

operate. It is important to note that individuals

with color deficiency may not see red or green laser

light very well, depending on their particular impairment (16), and could be at increased risk of

overexposure and injury from unknowingly staring

into the laser beam.

Laser pointers can pose a threat to commercial

aviation safety. The most serious recorded aviation

incident occurred on October 29, 1997, when an

Airworld Airbus carrying passengers enroute from

Crete, was illuminated by laser light about two

miles from Manchester Airport (England) at an

altitude of 600 feet AGL. While the plane was on

approach, the captain was forced to look away as a

laser pointer illuminated the cockpit (14). The

Civil Aviation Authority warned the public that

endangering an airline pilot in-flight is a criminal

offense carrying a maximum two-year jail sentence.

As a result of this and other incidents, the British

government subsequently banned the sale of more

powerful laser pointers (i.e., those with a maximum

power output > 1 mW) (see Figure 4).

In the United States, there have been numerous

reports of laser pointers illuminating aircraft inflight. The City of Los Angeles Department of

Airports has reported several laser illuminations

around their airports and is currently documenting

such incidents to quantify the extent of the problem. Reports of laser incidents from the Sacramento, CA, and Tucson, AZ, areas have also been

documented. Authorities have confiscated laser

pointers from perpetrators, counseling some and

arresting others. The danger from laser pointer

illumination is the visible beam hitting an aircraft’s

Class

Max

Power

MW

Logotype Warning Labeling

I 0.0004 None Required None Required

II 1 CAUTION Laser Radiation – Do Not Stare into

Beam

CAUTION

(Irradiance < 2.5 mW/cm2

)

Laser Radiation – Do Not Stare into

Beam or View Directly with Optical

IIIA 5 Instruments

DANGER

(Irradiance ≥ 2.5 mW/cm2

)

Laser Radiation – Avoid Direct Eye

Exposure

IIIB 500 DANGER Laser Radiation – Avoid Direct

Exposure to Beam

Table 1: Laser pointer FDA classification and labeling requirements.
5

Wavelength (nm)

Relative Eye Sensitivity

Luminosity (Lumens/Watt)

300 400 500 600 700 800 530 630 650 670

0.1

0.2

0.5

2.0

5.0

20

50

200

500

10-4

10-3

10-2

10-1

100

Figure 3: The eye’s relative sensitivity as a function of the wavelength of visible light.

windshield, which can scatter light and completely

obliterate a pilot’s forward vision. In low-level

flight, such as that of emergency medical or police

helicopters, this type of exposure can substantially

increase the risk of accidents due to temporary

visual incapacitation, startle effects, spatial disorientation, or the loss of situational awareness. In

response to such incidents, recommendations to

modify the Code of Federal Regulations have been

initiated. This action will help provide a method to

effectively prosecute individuals who use lasers to

illuminate aircraft.

In summary, when used properly, the risk of eye

injury from a laser pointer is extremely low. An

individual who receives a transient exposure may

experience a dazzling effect, resulting in distraction

or temporary visual impairment. The duration and

severity of these effects varies between individuals

and with their state of dark adaptation at the time

of exposure. An eye examination to rule out permanent eye injury from a laser illumination should be

performed if afterimages persist for several hours or

if a loss of clarity is apparent. To reduce the risk of

eye injury, should they fall into the hands of
6

Figure 4: Low-level laser illumination viewed through an aircraft windscreen.

children or irresponsible individuals, Class II laser

pointers (rather than Class IIIA) are recommended

for use by the general public. An increase in the

perceived brightness of red laser pointers can be

achieved without the need for additional power by

selecting those that emit light of wavelengths shorter

than 670 nm. While Class IIIA laser pointers can

continue to be used by responsible adults, they

should be replaced by lower powered pointers

whenever possible. Finally, to minimize the threat

to aviation safety, pilots should be educated on the

dangers of in-flight laser illumination and how to

best compensate for its debilitating effects. Although the FAA has established guidelines to protect flight crewmembers from laser illumination

during terminal operations, additional regulations

may be necessary to defend against the careless or

malicious misuse of these devices.

REFERENCES

1. Department of Health and Human Services,

Public Health Service, Food and Drug Administration. FDA issues warning on misuse of laser

pointers. P97-45. Dec 18, 1997. Available at:

http://www.fda.gov/bbs/topics/NEWS/

NEW00609.html

2. American Academy of Ophthalmology. Ophthalmologists concerned about laser pointers:

Growing number of eye injury cases reported

among children. Oct 6, 1998. Available at:

http://www.eyenet.org/member/comm/

media_relations/98/laser_warning.html

3. Herb M. Laser pointers: A new problem facing

law enforcement officers. J Am Optom Assn. May

1999: 70(5):283-4.
7

4. Yolton RL, Citek K, Schmeisser E, Reichow

AW, Griffith T. Laser pointers: Toys, nuisances,

or significant eye hazards? J Am Optom Assn.

May 1999; 70(5):285-9.

5. Marshall J. The safety of laser pointers: Myths

and realities. Br J Ophthalmol. Nov 1998;

82(11):1335-8.

6. Sell CH, Bryan S. Maculopathy from hand held

diode laser pointer. Arch Ophthalmol. Nov 1999;

117(11):1557-8.

7. Cline D, Hofstetter HW, Griffin JR. Dictionary

of visual science, 4th Ed. Radnor, PA:Chilton

Trade Book Publishing. 1989.

8. Sawyer M. Unauthorized laser sources in the

NAS. Presentation at the Society of Automotive

Engineers G-10(T) Meeting. Phoenix, AZ, Jul

13-17, 1999.

9. Leithauser D. Bad idea: Aiming light at police

helicopter. Orlando Sentinel. Aug 17, 1996.

10. Nguyen DP. Police pilot temporarily blinded

by laser beam. The San Diego Union Tribune.

Crime Watch 16. Jun 1998; pp2:7, 8:B-6:2.

11. Birkland D. Flashing laser at helicopter lands

teen in trouble. Seattle Times. Jul 1, 2000.

12. Luttrull JK, Hallisey J. Laser pointer-induced

macular injury. Am J Ophthalmol. Jan 1999;

127(1):95-6.

13. American National Standards Institute. American national standard for safe use of lasers. New

York, NY. ANSI Z136.1-2000.

14. Rockwell RJ, Jr., Ertle WJ, Moss CE. Safety

recommendations of laser pointers. J Laser Appl.

Aug 1998; 10(4):174-80.

15. American Optometric Association. Recommendations for the use of laser pointers. Dec 1998.

16. Romino PE. Laser pointers and color blindness.

[Letter] Ophthalmol. Oct 1998; 105(10):1797.
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