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Speed Measurement Laboratories, Inc., Report SL1097-14Laser Wars

Speed Measurement Laboratories, Inc.

Report SL1097-14, 15 October 1997, Laser Countermeasures

Photos and text by Carl Fors, Speed Labs

Overview - There are some 200,000 radar guns in operation in North America. A recent speed enforcement tool is the use of infrared laser guns operating at a 904 manometer wavelength. Over 30,000 laser guns are presently being used by law enforcement. In Ohio, a laser gun is standard equipment in all 435 state police vehicles. Laser has distinct advantages over traditional radar guns. At five hundred feet the laser's elliptical beam is a mere 18" wide compared to X band radar at one hundred and fifty-five feet. Laser works in a monochromatic format with a narrow spectrum by emitting infrared via a gallium arsenide diode at extremely high power. Infrared light is sent by the laser gun in a series of predetermined pulses, in excess of 300 per second, at the speed of light, 186,000 miles per second. Each emitted pulse is timed when it leaves the laser gun and when it returns. The difference from the time it leaves and returns is then computed in miles per hour. All this takes less than 1/3 of a second. Laser looks for flat, reflective surfaces of the target vehicle such as the front license plate. In the eighteen states and five Canadian provinces with no front plate, the laser is aimed at the headlights. Vehicular shape and color effect the laser gun's ability to target a vehicle. A black Firebird with pop-down headlights and no front plate is extremely difficult, if not impossible, to measure. A white car at 1,000 feet has 10 times the reflectivity of a black car at the same distance. A large eighteen wheeler with chrome bumpers is a sitting duck. Laser's effective range when targeted at the front of a vehicle is approximately 1,000 feet. From the rear up to 4,000 feet. Rear reception is assisted by the reflectors in tail lights and the square back design of most vehicles.

Laser has several advantages over radar and several disadvantages. Laser can target individual vehicles in a group, radar can't. Radar/laser detectors are of little use when confronted with laser. A detector mounted on the windshield at the traditional aiming distance of laser, i.e. 800 feet from the gun, most likely will give no alert when the laser is aimed at the front plate. It is outside of the laser's 30" elliptical beam width. Unlike radar with it's scattering microwave emissions, laser's infrared has no scatter alerting a vehicle trailing the target vehicle with a detector. Laser can not be used in the moving mode, it must be stationary. Most state enforcement agencies have passed on using laser for this 'reason. Laser is most prevalent in metropolitan areas with one officer on an overpass operating the laser and officers lined up on entrance ramps waiting for the radio to I.D. the offender. Similar to radar, laser can not be used in the rain, snow, or high dust environments. Laser takes precise aiming, radar does not. Like radar, laser is susceptible to cosine error. Cosine Error is the angle from O' perpendicular to the target vehicle. The greater the cosine angle the greater the error. However, 9 cosine error is always in favor or of the motorist, i.e. speed readings will be proportionally less than actual speed of the target vehicle. Sweep Error is manifested when the laser is aimed at one part of the vehicle, say the license plate, and due to the motion of the operator, the laser also targets a side mirror during the same trigger pull. Sweep Error adds to the real speed of the target vehicle. Reflection Error is next. On very hot days with low humidity a visible mirage/reflection -E, Engineer Dave Adams uses REPLACE! the target vehicle is created. In many cases, when the laser is aimed at 04 manometer IR camera the target vehicle the infrared beam also receives readings from both the target vehicle and the mirage causing a Sweep Error. Overexposure error is last. When a laser gun receives an extremely powerful reflective signal, such as a sun flare off a vehicle, the computer's timer can't see the return 904 manometer signal it sent. It can't compute a speed reading. In general, the laser gun is looking for the strongest return reflection of its own emitted beam for speed computation.

Countermeasures - Radar/laser detector evaluations have consistently reported detector inability of providing advanced warning to police laser guns. Laser citations are going up. In 1996, the Ohio State Police wrote some 107,000 laser citations. Beginning in 1995, the market saw entry of laser countermeasures from established and new companies. K-40 introduced their Laser Defuser, Rocky Mountain Radar announced the Phazer, Lidatek promoted Laser Echo and license plate covers touted their ability to thwart laser beams. In late 1996 and early 1997, new laser countermeasures emerged, i.e. Laser Blinder, Laser Buster, Rocky Mountain Radar's Phantom, Laser Plate, Laser Light, Laser Sun, T 3 Alpha Plate, Taylor Bell Plate, TeleRadar/Laser. Car and Driver Magazine gave positive reports on Laser Echo and K-40's Laser Defuser as products in evolution. Legalities-Explicit Federal Regulations prohibit the use or sale of devices designed to jam radar under Code Of Federal Regulations CFR, Part 15, Part 90. John Reed, senior engineer, Federal Communications

Commission, Technical Rules Branch, was quoted in the El Paso Times (2/25/97) when he said, "both active and passive radar jammers are illegal and punishable with fines, and in some cases, jail time. Manufacturers as well as jammer owners are culpable. You can not interfere with radio (radar) signals; that's what it comes down to." Operation of a radar jammer is considered to be a federal felony punishable with fines up to $75,000 and one year in jail. Jamming laser is another story. There are no federal laws prohibiting jamming laser. Active laser devices, i.e. those that transmit 904 manometer, are governed by the United States Food and Drug Administration, Center for Devices and Radiological Health under Code of Federal Regulations, CFR 21, subpart 1040. The FDA classifies such devices for safety, especially to the eyes. The highest rating is Class IIIb. If you own a jammer, how can you test it? Surely you wouldn't go to the police. department and say, "Officer I just bought a jammer to break the law. Would you test it for me? This has been the problem. Many unscrupulous companies have introduced products designed to take your money and only jam the truth. Speed Measurement Laboratories, Inc., a.k.a. Speed Labs was asked by several magazines to test these new laser countermeasures for effectiveness and report the findings. Field testing was conducted over a nine month period at three different test sites. Guns were operated by state police officers, retired police officers, radar and laser gun representatives, and Speed Labs staff.

Field Testing - Each laser countermeasure was run at both the LTI 20/20 Marksman and Kustom Pro Laser H laser guns. Test vehicles were driven at 30 mph and 60 mph, with the aiming point at determined distances of 1,000 and 750 feet

from the laser gun. The laser guns were aimed at both the front license plate and the headlights. Drivers counted down, "three, two, one" when they reached the aiming point cone and the laser guns were triggered. Test vehicles were in

two way radio communication with the laser source. Jamming duration was recorded in both distance and time as measured with stop watches. All jamming devices were assessed compared to what the operator's manual of the particular jamming device said the device would do. Activities were covered by the Associated Press, NBC, CBS, ABC national and local affiliates. The test activities were witnessed by more than sixty people including the El Paso Police Department, Fort Worth Police Department, Texas Department of Public Safety and numerous newspaper accounts. The laser guns were operated in accordance with accepted police practices and consistent with operation manuals of the laser gun manufacturer. Each countermeasure was given three runs at each laser gun in each category. In the case of Laser Echo and K-40 Laser Defuser Plus, both devices were tested on two -separate occasions at two different sites in the same categories.

The Players K-40's Laser Defuser Plus consists of a license plate mounted receiver / transmitter and an in-cabin mounted annunciator. The annunciator sounds an alarm of 91 dB when encountering laser. The transmitter is an array of LEDS tuned to 904 manometer under low power which does not require certification by the FDA. The license plate mounting bracket is provided. Defusers may be mounted on both the front and/or rear license plates. K-40 is an established company offering many products including CB radio antennas, remote and dash mounted radar detectors, and laser countermeasures. Laser Defuser's LEDS interfere with the reflected pulse timing of the laser gun's transmissions. K-40's Laser Defuser Plus claims to jam laser guns from targeting to the gun. K-40 is manufactured in the USA. K-40's Defuser Plus comes with a speeding ticket guarantee. Laser Echo comes from Lidatek. It is a high powered using a gallium arsenide laser diode. It's certified to FDA standards as a Class IRb device. Laser Echo claims to jam laser guns for five seconds with an accompanying five second warning from an in-cabin annunciator at 93 dB. The limited, five second duration is necessary to protect the gallium arsenide laser diode from over-heating. Customer testing of operation is possible by strobing a camera flash at the receiver/transmitter. 'ne license plate mounting bracket is provided with anti-theft mounting bolts. Laser Echo may be mounted on front and/or rear plates. Laser Echo is-manufactured in the USA. Laser Echo transmits a stronger signal than the laser gun's own reflected signal. Laser Buster, formally Laser Zapper, comes from Brazil. It is a license plate mounted LED bank with an in-cabin annunciator sounding laser alarms at 90 bB. Since it is low powered it does not require FDA certification. Laser Buster may be mounted to front and/or rear license plates. Laser Buster claims to jam both laser guns from targeting point to the gun and is active only when receiving a laser signal. Laser Buster has no license plate mounting bracket but uses the bolt holes of both front and/or rear plates for attachment. Laser Buster claims to place 904 nanometer pulses between the return laser gun signal.

Laser Blinder is from CTS Electronics AB, Mora, Sweden. CTS has a U.S. marketing office in Houston. Blinder consists of a master and a slave transmitter both mounted in the front grill with one by the passenger headlight and one by the license plate. Blinder constantly transmits high-powered infrared emissions. Blinder has no in-cabin audible warning system. Transmitter mounting em are provided for installation. Horizonal transmitter placement is essential. Blinder may also be rear mounted. Blinder claims to transmit a stronger 904 nm signal than the laser gun's reflected signal.

Rocky Mountain Radar markets two products claiming to jam laser, i.e Phazer and Phantom. These products also claim to jam all bands of radar. Both are classified as passive devices. The manufacturer asserts both the Phazer and Phantom jam laser guns by constantly emitting infrared beams back to the laser gun. Neither device provides audible warning of laser's presence. Both products are powered by the cigarette lighter and made in the USA. Both the Phazer and Phantom _come with a speeding ticket guarantee.

Laser Light consists of two high powered- quartz halogen driving lights covered with 904 manometer infrared filter film. Laser Light is constantly on and with transmissions invisible to the human eye. There is no in-cabin warning system with Laser Light. Laser Light may be mounted behind the grille or attached to the bumper. Installation requires g to establish mounting holes. Laser Light is Canadian in origin. Laser Light's transmissions do not come under restrictions of the FDA.

There are three license plate covers on the market, i.e. T 3 Alpha, Taylor Bell, and Laser Plate. All claim to absorb or to interfere with the laser beams reflection back to the gun's computer. T3 Alpha is slightly green in tint and has its own license plate mounting bracket. The Taylor Bell product is clear while Laser Plate has -a distinctive frosted appearance. All claim to interfere with the laser gun's maximum- targeting ability. All are made in the USA. The plates provide no protection when the laser is aimed at headlights in states and provinces with no front license plate. Laser Plate is brittle and can crack if too much pressure is applied during installation.

Laser Sun is a small (approximately 2" x 4") driving light with an infrared filter covering the light's surface. It must be bolted to the vehicles bumper. Teleradar is a jammer in the shape of a cellular phone claiming to jam all radar bands and laser., Speed Labs was promised by Teleradar two samples almost two months in advance of the most recent, Sept. 97, test but the products did not arrive.

CONCLUSIONS Performance of laser countermeasures is rated on a scale of "O" to "10" with ten being the highest score. This scale subjectively reports each product's performance against by both the LTI 20/20 Marksman and the Kustom Pro Laser II laser guns. Other factors like in-cabin warnings were taken into account in arriving at a numerical score. "JTG" indicates the laser countermeasure totally jammed to the gun the identified laser gun 90% of the time from the various aiming points. This 90% rating of "JTG" considers laser gun operator targeting errors. The score of "0" means the device had no jamming effect on laser guns whatsoever!

ProductLTI 20/20Kustom Pro Laser

K-40 Laser Defuser Plus10 (JTG)9 (JTG)

Laser Echo99

Laser Buster9 (JTG)8

Laser Blinder710 (JTG)

Laser Light53

T3 Alpha Plate22

Taylor Bell Plate01

Rocky Mountain Radar Phazer00

Rocky Mountain Radar Phantom00

Laser Sun00

Laser Plate00

A 45-minute video summary of field testing of all jammers and new radar detectors may be purchased for $19.95.

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