U.S. Department of Justice Office of Justice Programs National Institute of Justice

National Law Enforcement and Corrections Technology Center March 1996 National Institute of Justice Jeremy Travis, Director Scoping Out Night Vision In the United States today, there are more than 50 companies that either manufacture or distribute night vision equipment. Departments considering a purchase of this equipment will encounter a potentially confusing array of technical specifications and terminology, and mistakes can be costly. To help departments evaluating night vision systems to make informed decisions, this bulletin of the National Law Enforcement and Corrections Technology Center (NLECTC) presents basic information on night vision technology and terminology, factors to consider when evaluating night vision systems, and new developments in night vision.

Background visible light that is available at night— contrast—when a pinpoint source of moonlight, starlight—and to invisible bright light, for example, a car’s head- The most widely used night vision aid in light from the near-infrared range of the lights or the flash of a cigarette lighter, law enforcement is image intensifier (I2) spectrum. The image intensifier tube enters the field of vision. Because such equipment. Developments in I2 technol- multiplies the light it takes in many bright, concentrated sources of light ogy are categorized in terms of “genera- thousands of times, essentially amplify- could induce image degradation/shut tions.” To date, there have been four ing the brightness of the image seen down and even tube damage, later generations of night vision devices, through the device. This process is generations of night vision devices numbered from zero through three. described in more detail below. In incorporated several features to protect Night vision technology was originally situations where there is almost no against bright light. Even with these developed to give the U.S. Armed Forces ambient light, such as on an overcast safety features, care should be taken to the tactical advantage of seeing at night night or inside an unlit building, an avoid such exposures and to keep the or under other conditions of low light infrared light source is required. Many objective (front) lens capped during the without using searchlights that would night vision systems have an integrated day and when the unit is not in use. reveal their position. The first night infrared light-emitting diode (IRLED) The development of the microchannel vision aids—“generation zero” (Gen that can be used in situations where plate (MCP) in the late 1960’s brought 0)—were sniper scopes that came into ambient illumination is low. An auxiliary the second generation (Gen 2) in night use during World War II and the Korean infrared light source, such as a high- vision. (See figure 2.) The MCP elimi- conflict. These were not true image intensity flashlight fitted with an infrared nated the need for three-stage light intensifiers, but rather image converters, filter, can also supply the light required amplification and thereby reduced the which required a source of invisible to operate a passive device. size, weight, and distortion of the image infrared (IR) light mounted on or near The “starlight scopes” developed during intensifier tube. With the MCP, night the device to illuminate the target area. the early 1960’s for use in Vietnam were vision goggles and hand-held viewers The objects in the target area reflected the first generation (Gen 1) of I2 devices. this IR light, which the device converted Some Gen 1 equipment is still in service. to visible light. Because they cannot In Gen 1 devices, three image intensifi- New NIJ Publications function without auxiliary IR light, Gen ers were connected in a series, which 0 devices are referred to as “active.” Available upon request is NLECTC achieved a high level of light amplifica- Bulletin, “Positional Asphyxia—Sud- The development of the image intensifier tion but also made the scopes longer and den Death,” dated June 1995. Cur- tube brought clearer, brighter image heavier than future night vision devices rently in production is a report on the quality to night vision. I2 devices are would be. (See figure 1.) Gen 1 devices Second Annual Law Enforcement Technology for the 21st Century con- called “passive” because they do not produce an image that is clear at the ference, held in June 1995 in Wash- center but distorted around the periphery require an auxiliary source of illumina- ington, D.C. Please contact NLECTC tion. These devices are capable of and also subject to “streaking” and for availability of these publications. responding both to the limited amount of “blooming”—temporary loss of became possible. The MCP also pro- Figure 1. First-generation (Gen 1) image intensifier vided much more robust operation when bright lights were in the field of view.

Third-generation (Gen 3) image intensi- Intensifier Tube fiers were developed in the mid-1970’s Objective Lens Electron Optics Eyepiece and became available during the early 1980’s. Gen 3 introduced two major technological improvements: Available Focused Stage Stage Stage Intensified Light Light 1 2 3 Image n The gallium arsenide (GaAs) photo- Photocathode Photocathode Photocathode cathode, which increases the tube’s sensitivity to registering light from the near-infrared range of the spec- Field Iris Phosphor Phosphor Phosphor Screen Screen Screen trum, enables it to function at greater Fiberoptics detection distances and improves Plates system performance under low-light conditions. (Gen 1 and Gen 2 devices The tube is actually a sequence of three image intensifiers, each comprising a photocath- ode and phosphor screen. use an S–20 multialkali photocathode.) n Application of a metal oxide ion barrier to the MCP, which increases array. When an electron from the conditions will the equipment primarily the life of the image tube. The photocathode enters a given channel, be used? Mobility? Stationary surveil- operational life of Gen 3 image it strikes the channel wall, initiating lance? Hand-held discreet observation? intensifier tubes is in excess of 7,500 an avalanche process that results in Videotaping? Photography? Some night hours; that of Gen 2 tubes is about several hundred electrons exiting the vision equipment can be adapted to more 2,000 to 4,000 hours. other end of the channel. than one application. The best way to make an informed purchase is to begin n The electrons exiting the MCP How Image Intensifiers Work with an analysis of your department’s bombard a phosphor screen that needs. All I2 systems employ an objective converts their energy into a green (front) lens, an image intensification form of visible light. The process is This analysis should also take stock of tube, and an ocular (eyepiece). Available similar to the way images are pro- the equipment you presently have on light enters the objective lens and is duced on a television screen. hand. If you plan to use your night amplified as it passes through the image vision equipment for photography and n intensification tube. The process is as Because this light is in the same your department already has a 35-mm follows: pattern and proportion as the image camera and an assortment of lenses, look formed by the objective lens, the for a night vision device that can be n The light is focused on the photocath- image in the device’s eyepiece equipped with an adapter that will allow ode, the first component of the image corresponds precisely to the image you to use your existing lenses. Video intensifier tube. The photocathode is being viewed. cameras can also be coupled to certain an electron-emitting, photosensitive night vision devices with special relay screen located where the film in a Evaluating Image Intensifiers lenses that are adaptable to most camera would normally be. It absorbs 2 common lens mounts. High-intensity the light’s energy and converts it into Today I night vision equipment is flashlights can be converted to invisible electrons. available in the form of hand-held viewers for use with one eye (monocu- searchlights for use with night vision n Next, these electrons are accelerated lar) or both eyes (biocular or binocular); systems by attaching infrared filters. and multiplied. In Gen 1 tubes, this goggles that allow the user to walk, run, Where will your equipment be used? Gen was accomplished with three stages of or pilot a vehicle; binocular observation 2 equipment is generally a good choice for photocathode amplification. Gen 2 devices that provide magnification; and use in urban environments, where there is and Gen 3 tubes use a single photo- weapon sights. The first question to more ambient light. In rural environments, cathode and a microchannel plate address when considering an investment or in situations where the ambient illumi- comprising more than 2 million in night vision equipment is application: nation is extremely low, Gen 3 equipment microscopic hollow-glass conducting For what purpose and under what is preferable. channels fused into a disc-shaped

2 Performance Factors Signal-to-noise ratio Gain The best means of evaluating whether The signal-to-noise ratio (SNR) is a This is a measure of brightness. The gain the equipment you propose to purchase measurement of the amount of light of a night vision device is the number of will serve your needs is an onsite reaching the eye divided by the amount of times it amplifies the light entering the demonstration under your typical “noise,” or static disturbance, perceived by device. Tube gain, measured in the tens operating conditions. In comparing the the eye, and is considered to be the best of thousands, represents the actual performance specifications of different single indicator of a night vision device’s degree of amplification generated in the night vision systems, the following are low-light performance. The SNR tube. However, because tube gain is the key parameters to consider. indicates the low-light resolution of the reduced by other system components— image intensifier tube, that is, how well lenses, optics, filters—the more impor- Photosensitivity it can distinguish between objects that tant measurement to evaluate is system are close together under low-light gain, which is measured in the thou- This value measures the capacity of a night conditions: The higher the SNR, the sands. vision device to detect light and convert it smoother the image under low-light to electrons. Photosensitivity is the chief conditions. An example of an SNR- Gain should always be evaluated in factor determining the signal-to-noise ratio limited image is reception of a broadcast conjunction with photosensitivity and (SNR), explained below. A higher television station in a fringe area. SNR. If the latter two are poor but gain photosensitivity generally results in a value is high, the image produced by the higher SNR. Photosensitivity should The SNR is dependent on several system will be poor even though it is bright reference a 2854K or 2856K input elements in a night vision device and can due to high “noise” content. A very high blackbody distribution to ensure an input be calculated in various ways to get the tube gain can lower the quality of the spectrum with the appropriate IR compo- results desired. The U.S. military image by creating more tube “noise.” Very nent. generally specifies a minimum SNR of high gain values may also mean that the 4.5 (@1.2 x 10-6 FC input) for Gen 2 tube is driven very hard, which would The critical variable in evaluating tubes and 16.2 (@1.0 x 10-5 FC input) shorten its operational life. U.S. military photosensitivity is the area of the light for Gen 3 tubes. To ensure adequate low- specifications call for a tube gain of 20,000 spectrum in which it is measured. For light performance, the objective lens to 35,000 and a system gain of 2,000 to night vision, performance in the near- should have an f-number not exceeding 3,000. infrared range of the spectrum is crucial. 1.7 and a t-number not exceeding 2.0. Equivalent background input Figure 2. Basic configuration of second-generation (Gen 2) image intensifier Equivalent background input (EBI) is a measure of the tube’s output brightness when there is no light entering the tube. Fiberoptics Excessive EBI tends to reduce contrast at Electron low light levels and high temperatures Objective Lens Optics Eyepiece because EBI doubles for every 3-4 degree centigrade rise in temperature. To help ensure proper low-light perform- ance, it is important to specify military- Available Focused Intensified level EBI, with no more than 2.5 x 10-11 Light Light Image lumen/cm2 at a temperature not less than Photocathode 21 degrees centigrade.

Field Iris MCP Phosphor Screen Resolution Like gain, resolution—the sharpness of The microchannel plate (MCP) eliminated the need for the three-stage light amplification image contrast—is measured both in used in Gen 1 devices. The configuration of the third-generation (Gen 3) image intensifier terms of the image intensifier tube and of is much the same, but the photocathode, MCP, and phosphor screen are much closer the overall system. System resolution together. Two other factors distinguish Gen 3 intensifier tubes from Gen 2 tubes: use of a gallium arsenide (GaAs) photocathode rather than the S-20 multialkali photocathode used takes into account the quality of the in Gen 2 tubes, and the application of a metal oxide film to the MCP to create an ion system’s optics and is the more accurate barrier. measure of what the viewer actually sees. Tube resolution becomes an

3 important criterion in comparing systems Weather resistance electrons leaving the photocathode. with similar optical qualities and filters. The higher the electron energy to the Fogged lenses are useless; therefore, When the resolution of different night MCP, the greater the number of ions system resistance to humidity and vision systems is measured in the same the MCP will generate. Because ion moisture is crucial. Look for the ability way, under the same conditions, and contamination from the MCP is the to float in devices that will be used on or using the same magnification, a higher primary contributor to the “death” of around water. Look, in any case, for resolution value means a sharper picture. the image tube, BSP is an extremely hermetic system seals, which protect the important protective feature. enclosed intensifier tube from moisture. Magnification and field n Metal oxide ion barrier: A metal of view Human Factors oxide film on the microchannel plate The total magnification of a night vision allows electrons from the photocath- Factors affecting ease of use should not device is determined by dividing the ode to pass through the MCP, but be ignored. How easy is the device to focal length of the objective lens by the traps ions, preventing them from operate in the dark, when the operator focal length of the eyepiece. As magnifi- contaminating the photocathode and cannot see the controls? How heavy is cation increases, field of view (FOV) thereby extending tube life. the unit? Can it be carried comfortably decreases, so that complete surveillance for extended periods of time? Does the When purchasing lenses for use with may require movement of the night vision on/power switch need to be depressed night vision systems, ensure that the device over the area of interest. At higher continually to operate the device? What antireflection coatings and imaging magnification, the amount of light captured kind of eyepiece does the device use? characteristics are optimized for near- may also be reduced. Long-range observa- Prolonged observation with a monocular infrared response (i.e., visible wave- tion or weaponsight applications, then, device may cause eye fatigue. Much less lengths up to 900 nanometers), as are require an image tube that performs well at eye fatigue is experienced with biocular some types of lenses for charge-coupled low light levels and/or high-performance or binocular devices. devices (CCDs). This will help ensure lenses. adequate performance in both high- and Consider the versatility of the device in Cost low-illumination situations. situations requiring different magnifica- The purchase price is only the first of the Another element to be aware of when tion. Some night vision devices use a costs of owning night vision equipment. evaluating the cost of operating a night fixed objective lens; others use inter- Maintenance and repair must be factored vision device is the type of battery it uses. changeable lenses, making possible the into the costs of ownership. All image Look for devices that take commercially use of a telephoto lens if needed. Use of intensifier tubes wear out over time and available batteries rather than batteries zoom lenses should be avoided because must be replaced. The life of the tube that must be ordered from a supply their optical quality tends to be poorer should be considered when purchasing a house. than that of fixed focal length lenses. system. The following protective features extend the life of an I2 tube: Distortion Know What You’re Getting n Automatic brightness control (ABC): All systems are subject to some distor- Although there are more than 50 compa- A circuit that automatically reduces tion in the image they produce. Minimal nies distributing or manufacturing night the voltage to the microchannel plate distortion is critical in weaponsights and vision systems in the United States when bright light enters the field of systems used for photography or video. today, only 2 U.S. companies manufac- vision. The ABC helps protect the I2 ture the image intensifier tubes used in Distortion manifests itself as a swim- tube from exposure to bright light that these systems: ITT and Litton. To know ming or swaying image as objects move would otherwise damage it and also what you’re getting: through the field of view, or as the provides limited protection to the user n Request a copy of the factory original system is panned. Degree of distortion is from bright flashes. tube data sheet for the system you usually included in the list of technical n Bright-source protection (BSP): A propose to buy. All I2 tubes made in specifications provided by the manufac- circuit that reduces the voltage the United States have a serial turer. Distortion should not exceed 5 between the photocathode and the number. The tube data sheet will list percent across the total field of view. microchannel plate when the system the manufacturer of the tube, the tube is exposed to a point source of bright serial number, and the operating light. BSP lowers the energy of parameters of the tube. This informa-

4 tion will enable you to verify the systems, making thermal imaging night n They can help see through most fog and salesperson’s claims. vision systems more accessible to the a few layers of foliage. A suspect or a average law enforcement agency. vehicle with a warm engine hidden in n Beware of systems claiming to use brush or woods will stand out more “surplus tubes.” These tubes may How it works clearly. actually have been rejected and removed from inventory because their Everything emits heat energy in the form n They are not subject to image “bloom- quality is suspect. of infrared radiation. Although the human ing,” cannot be damaged by exposure to eye is not sensitive to this energy, it acts bright light, and therefore will not n Avoid reconditioned tubes. The like light, and can be optically focused and automatically cut off when exposed to operational life of these tubes is collected. A thermal imaging system pinpoint sources of bright light. usually short, and their warranty focuses infrared energy on an electronic coverage is seldom comprehensive. transducer with thousands of tiny sensors. Thermal imaging systems offer advan- tages that go beyond seeing in darkness. n Exercise caution in evaluating night These sensors measure the difference in FLIR technology offers the ability to vision devices that use foreign-made temperature among the objects in the scene track suspects in a completely different tubes. The substantially lower cost of to a fraction of a degree and compare them way—by the heat registered by them- these systems makes them attractive, with the background. The thermal contrast selves and their vehicles. Thermal but they may not always adhere to is translated to visual contrast in shades of imaging systems can: U.S. performance standards. As with gray on a black and white monitor, creating a TV-like picture. These systems any equipment, study the warranty n Detect fresh footprints in snow. can be set to register heat as either white carefully and find out where you can Officers in Ottawa, Canada, used a (“white-hot”) or black (“black-hot”). get it repaired if it does fail and how prototype of a new mobile thermal long repairs usually take. Some Previously, FLIR systems required imager to track a suspect leaving a foreign manufacturers of night vision cryogenic cooling, which greatly building through snow. The suspect’s equipment also make extravagant increased their cost. The technological fresh footprints retained his body heat claims regarding “light gain” and breakthrough that has brought the cost of and glowed on the system monitor. amplification, but remember that too these systems down is use of either a n Reveal the presence of a concealed high a gain will actually detract from resistive or a ceramic material that weapon by thermal contrast. the overall image quality and shorten allows them to operate at room tempera- the life of the image intensifier tube. ture. n Link recently discarded evidence to a n suspect by virtue of the residual body Pay careful attention to the specific A relatively new thermal imaging system heat it radiates. In Dallas, Texas, a generation of the intensifier (i.e., Gen available to law enforcement agencies is suspected drug dealer threw away 0, 1, 2, or 3) being offered by the a camera on a panning mechanism that is bags of cocaine he had been holding manufacturer. mounted to the roof of a patrol car just when he heard a patrol car approach- behind the lightbar, allowing 360 ing. Because the officers were using a coverage around the vehicle. Video from New Developments in Night thermal imaging system, they were the camera is displayed on a television Vision: Thermal Imaging able to see the heat trajectory of the monitor inside the car. This system can Until recently, night vision has been bags leaving the suspect’s car also be mounted on boats. Other applica- nearly synonymous with image intensifi- window, thus positively linking the tions, such as rifle sights and hand-held cation. There is another night vision evidence to him. sensors, will soon be available for law technology, forward-looking infrared enforcement use. n (FLIR) or thermal imaging, which was Pick out vehicles that have recently developed for the U.S. military during been driven. In one documented the 1960’s. FLIR has been in use by law Unique capabilities instance, a thermal imager was instrumental in the arrest of a hit-and- enforcement for about 20 years, most Because they measure the heat emitted run suspect: Using a mobile unit commonly on helicopters and light by an object rather than the light re- mounted on their patrol car, officers airplanes. However, the extremely high flected by it, FLIR systems can do some in Dallas, Texas, were able to pick out cost of these systems (in excess of things that image intensifiers cannot: $100,000) was prohibitive for most the suspect’s car from among the police agencies. New developments in n They are effective in situations of others parked on a residential street FLIR technology are bringing the cost total darkness, with no need for by its warm engine, which stood out down to a level compatible with I2 supplemental illumination. among the other “cold” cars.

5 n Spot recently made tire skid marks. a thermal imaging system can detect. used. Room temperature thermal The lower the NET value, the better the imaging systems typically consume less n Pick up the warm water trail of a system performs. Typical NETs for law than 8 watts of power. Power consump- swimmer. enforcement applications are 0.2 degrees tion for cryogenically cooled thermal centigrade. Higher performance military imaging systems is typically more than Limitations systems have NETs of less than 0.05 10 watts. Look for devices that use Although thermal imaging systems offer degrees centigrade. commercially available or rechargeable some capabilities that image intensifier batteries, rather than batteries that must systems do not, they do have limitations: Resolution be ordered from a supply house. n Thermal imaging systems do not The resolution or sharpness of image in a Another feature to consider is the register detailed facial features; thermal imaging system is measured in availability of a video output to display therefore, FLIR video cannot be used terms of its instantaneous field of view images on a remote display, television, to make a positive identification of a (IFOV) in milliradians (mrad). [Note: or a standard format VCR tape. This suspect. I2 systems, on the other hand, 17.5 milliradians is equal to an angle of 1 feature is useful for both training and can delineate facial features in fairly degree in the instantaneous field of creating a permanent record of images good detail. view.) The lower the IFOV value, the viewed with the equipment. sharper the image and the longer the n Because infrared energy does not pass performance range of the sensor. Weight through normal glass, thermal systems Typically IFOVs for law enforcement cannot be used to monitor suspects applications are in the 1.0 to 1.5 mrad Hand-held thermal imaging systems inside vehicles or through building range. Higher performance military usually weigh less than 4 pounds. Long- windows. This is also the reason the applications have IFOVs of less than 1.0 range thermal systems with large optics system camera must be mounted on mrad. can weigh much more and are typically the roof of the patrol car, where it is mounted on a vehicle or tripod. conspicuous and at greater risk of Magnification and field of view being vandalized. Choosing a System The total magnification of thermal n Although FLIR systems can see imaging systems is determined the same The best way for departments to deter- through fog, such high-humidity way that it is for I2 systems: divide the mine whether they will be best served by 2 conditions do minimize thermal focal length of the objective lens by the a thermal or an I system, or both, is to contrast, degrading the quality of the focal length of the eyepiece. evaluate their needs carefully and insist image. on having an onsite demonstration under As the magnification of the thermal realistic operating conditions. sensor increases, the field of view (FOV) Performance factors decreases. Complete surveillance of an 2 To Comment or For As with I equipment, evaluating the area requires movement of the sensor. Further Information: thermal imaging system you propose to NIJ’s National Law Enforcement and purchase is best done in an onsite Cost demonstration under typical operating Corrections Technology Center main- conditions. The following key param- The purchase price of a thermal imaging tains a data base that identifies manufac- eters or performance specifications of the system depends on the performance turers of night vision equipment and thermal imaging systems under consider- (sensitivity and range), operating other law enforcement, corrections, and ation should be compared. temperature (cryogenically cooled or criminal justice products. room temperature), and application configuration. As with I2 equipment, For additional information, please call Sensitivity maintenance and repair must be factored NLECTC at 800–248–2742, or write to The sensitivity of a thermal imaging into the costs of ownership. Box 1160, Rockville, MD 20849–1160. system is typically described as the Noise Equivalent Temperature (NET), If the thermal imaging system requires measured in degrees centigrade for a batteries for operation, power consump- given optical f-number. This value tion should also be considered in the measures the temperature resolution or purchase decision. The higher the power the minimum temperature difference that consumption, the more batteries will be

6 NLECTC Bulletin l Interactive services, including a NIJ Charter criminal justice chat line and topic The NLECTC Bulletin is designed as board. Under NIJ’s charter, relative to its a forum for disseminating to the law l Data and publication services. grants program, the Institute is au- enforcement and criminal justice thorized to: communities the most current infor- JUSTNET can be accessed at the l Sponsor R&D to improve and mation on technologies relevant to following Internet address: strengthen the Nation’s system of your needs. We welcome your com- http://www.nlectc.org justice with a balanced program ments or recommendations for fu- of basic and applied research. ture Bulletins. For a copy of the JUSTNET user's l Evaluate the effectiveness of guide, call NLECTC. criminal justice and law enforce- NLECTC is designing data bases to ment programs and identify those help respond to agencies that want that merit application elsewhere. to know who manufactures a specific Grants Program l Support technological advances product and what other agencies may applicable to criminal justice. be using that product. Your contribu- NIJ’s grants program, operated by l Test and demonstrate new and tions to the Center’s information net- NIJ’s Office of Science and Technol- improved approaches to strength- work are important. What technolo- ogy, has supported research in nu- en the justice system. gies or techniques are you using that merous and diverse issues of impor- l Disseminate information from re- you would like to share with col- tance to law enforcement executives search, development, demonstra- leagues? Please call or write to the as well as to the officer on the street. tions, and evaluations. National Law Enforcement and Cor- Improving fingerprint and trace evi- rections Technology Center, P.O. dence identification and the devel- Box 1160, Rockville, MD 20849– opment of DNA standards are some 1160, 800–248–2742. of the more notable achievements. In the late 1980’s and early 1990’s, a renewed interest in less-than-lethal (LTL) weapons by the criminal jus- National Law tice system led Congress to allocate Enforcement JUSTNET special funding to NIJ to begin an and Corrections R&D program in this area. Contact JUSTNET (Justice Technol- Technology Center ogy Information Network) for online In late 1992 and early 1993, NIJ The National Law Enforcement and access via the Internet and World initiated an expanded program to Corrections Technology Center Wide Web (WWW) to information investigate all aspects of this issue is supported by Cooperative Agree- about new technologies, equipment, and to develop a broad-based re- ment #95–IJ–CX–K002 awarded by and other products and services search program that would lead to the U.S. Department of Justice, available to the law enforcement and new tools and use-of-force options National Institute of Justice. corrections communities. Under the for law enforcement officers. The auspices of the National Institute of program has evolved into one that The National Institute of Justice is a Justice, U.S. Department of Justice, looks not only at weapons but at the component of the Office of Justice JUSTNET is a service of the Na- sociological aspects of the use of Programs, which also includes the tional Law Enforcement and Correc- LTL weapons, e.g., liability and com- Bureau of Justice Assistance, Bu- tions Technology Center (NLECTC). munity acceptance issues. reau of Justice Statistics, Office of By accessing the JUSTNET home Juvenile Justice and Delinquency page on the Internet’s WWW, law It has also become clear, however, Prevention, and Office for Victims of enforcement and corrections repre- that technologies other than weap- Crime. sentatives can take advantage of ons may effectively address the same the following three primary service operational goals of reducing the options, which in turn provide ac- incidence of death and injury to offi- cess to additional criminal justice cers, suspects (or prisoners), and Web sites: the public when force has to be used to effect an arrest or combat violent l News and information services. behavior during transport or other custodial duties.

7 Regional Contacts: National Law Enforcement and Border Research and Technology Corrections Technology Center, Center Office of Law Enforcement Rocky Mountain Region 1250 6th Street Technology Commercialization 2050 East Iliff Avenue Suite 130 316 Washington Avenue Denver, CO 80208 San Diego, CA 92101 Wheeling, WV 26003 Phone: 303–871–2522 Phone: 619–685–1491 Phone: 800–678–6882 Fax: 303–871–2500 Fax: 619–685–1484 Fax: 304–243–2539 POC: James Keller POC: Chris Aldridge POC: Jerome Bortman (interim) Contact information for these offices is National Law Enforcement and Office of Law Enforcement Standards, subject to change. Other sources of Corrections Technology Center, information on law enforcement and National Institute of Standards and West Region Technology corrections technology are also available. The Aerospace Corporation Please call NLECTC at 800–248–2742 Building 225, Room A323 2350 East El Segundo Boulevard Gaithersburg, MD 20899 or write to Box 1160, Rockville, MD El Segundo, CA 90241–4691 20849–1160. Phone: 301–975–2757 Phone: 310–336–2171 Fax: 301–948–0978 Fax: 310–336–2227 POC: Kathleen M. Higgins POC: Robert Pentz Information in this Bulletin is drawn National Law Enforcement and National Law Enforcement and from numerous sources including the Corrections Technology Center, Corrections Technology Center, Marine Aviation Manual and material Southeast Region Northeast Region supplied by manufacturers of night 3725 Peppermill Parkway 26 Electronic Parkway vision equipment. We thank Bob Doms North Charleston, SC 29418 Rome, NY 13441–4514 for his valuable input and technical Phone: 800–292–4385 Phone: 315–338–0584 review. We also thank the U.S. Army Fax: 803–297–7776 Fax: 315–338–6124 Night Vision & Electronic Sensors Directorate and the Department of POC: Steve Bishop POC: John Ritz Defense Advanced Research Projects Agency for their review and comments.

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