Thermal systems are excellent for locating people in wooded areas. Photo: FLIR Systems

Thermal systems are excellent for locating people in wooded areas. Photo: FLIR Systems

If your only tool is a hammer, all your problems will look like nails. That's a huge mistake when it comes to the work we do in law enforcement. Whether it's bullets, protective vests, uniforms, duty firearms, or night vision devices, we need the right tools for a particular job.

Quite a few procurement officers have absolutely no idea what the folks in the field really need when it comes to night vision. Nor do they understand the different uses of thermal imaging versus light amplification and when they should be deployed.

There's a reason for this lack of interest and lack of knowledge. Night vision technology is complicated and at one time it was prohibitively expensive, the stuff that only a few agencies and the military could afford. So let's demystify the stuff, discuss its benefits, and talk about how and where you can get it, and why the price is dropping into your affordability range.

Thermal Imaging

Scientists have been studying thermal energy for hundreds of years. Back in the 1700s astronomer William Herschel started identifying the infrared part of the spectrum, invisible to the human eye, by looking at the sun with his telescope using different colored filters. There wasn't much practical application of this science until shortly after World War II when the U.S. Air Force began using downward-looking infrared cameras for reconnaissance missions.

Thermal energy comes from a combination of sources. Some things, including people, engines, and machinery create their own heat, either biologically or mechanically. Other things such as land, rocks, and vegetation absorb heat from the sun during the day and then radiate it off during the night.

Thermal cameras are actually sensors that see and measure thermal energy emitted from an object. Thermal or infrared energy is light that's not visible because its wavelength is too long to be detected by the human eye; it's the part of the electromagnetic spectrum we perceive as heat. Everything with a temperature above absolute zero (-459.67 degrees Fahrenheit) emits heat. So even ice cubes emit infrared energy.

What we see when we look through a thermal camera or scope is a representation in the visible spectrum of the infrared energy emitted by objects. Some thermal camera systems present this image in black and white while other more expensive systems present it in colors that differentiate between temperatures. The color aspect is critical to the fire services so firefighters can make decisions on entering a structure fire safely and maybe even determining the origin of the burn. But we cops mostly deal with people, so color output isn’t a huge factor; it’s nice to have but not mission critical.

Night Vision

Many people think night vision devices were first developed in the 1960s and were a product of the Vietnam War. Not so. The Allgemeine Elektrizitäts-Gesellschaft or German Electricity Company developed the first usable systems in 1939.

During World War II some German Sturmgewehr 44 assault rifles were equipped with a "Vampyr" active night vision system. These earliest, man-portable, Generation 0 devices consisted of a 30-pound battery in a wooden case for the main light and another smaller battery for the image converter. The light was a 35-watt tungsten spotlight equipped with an infrared filter. The battery system was strapped to a pack frame and the light and scope were attached to the rifle. Imagine having to lug that monstrosity around during your regular patrol shift. Thankfully, you won’t have to do so. Today's night vision systems are passive—not requiring any external light source—and can fit into the palm of your hand.

Those old systems were Generation 0. Gen 1 systems used in Vietnam were true "starlight" systems that required no external IR light because they amplified existing ambient light, hence their nickname "Starlight Scopes."

Later, Gen 2 systems incorporated a micro channel plate consisting of a wafer manufactured from thousands of hollow glass tubes to boost light amplification to 30,000 times. Increasing layers of wafers can achieve 1 million times amplification.[PAGEBREAK]A micro thin layer of aluminum oxide and a gated power supply were added to achieve Gen 3 technology. Gen 4 systems are currently the mostly highly refined Gen 3 tubes. There’s been only one type of a true Gen 4 tube manufactured. It didn't measure up to the failure standards of military specs and was rejected.

Which Do You Need?

Whether you need night vision or thermal imaging or even both is a matter of what mission you wish to accomplish, your training, and your agency's financial resources, including grants.

If your mission requires you to see fine detail at night, then you probably want to use light amplification night vision. The lens and sensor components in these systems have been highly refined and can offer you the ability to recognize faces or even read nametags from a distance.

In contrast, thermal systems are excellent for picking out and locating people who are hiding or lost in woods or other large search areas. They're also great for finding discarded evidence such as a gun that is still warm from handling or telling you which car in a parking lot was just driven. But like night vision it has its weaknesses. Since thermal relies on the differences in radiated infrared energy, facial recognition and super-fine detail suffer.

There are cases where night vision can be defeated where thermal cannot. One such instance involves a technique used by some sophisticated drug dealers. They pull their cars into a circle with the headlights facing the center and during darkness make their deals and exchanges in the center bathed with intense light. Officers using night vision for surveillance are "blinded" by this tactic. But it's ineffective if the officers have thermal imaging on their side. Since thermal relies on reflected IR radiation, it cuts right through the white light.

Patrol Operations

In far too many agencies, night vision equipment and thermal imaging are only available to special units. But if I were king, I would decree that all patrol cars and officers be equipped with light amplification night vision devices.

We need to see at night and a flashlight isn't always the answer. The bad guys can see us coming and see where we’re looking. For the price, there's no beating it when it comes to surveillance, and it puts us "one up" on most crooks.

In my kingdom, Thermal would go to tactical teams, search teams, and supervisor cars. You can’t beat it when searching wooded areas for a suspect, lost child, or tossed evidence.

WHERE TO GET IT

American Technologies Network

American Technologies Network (ATN) is a leading manufacturer of precision optics, including night vision, daytime scopes, thermal imaging, and binoculars. ATN recently moved to a new, larger, and more technologically advanced distribution and manufacturing facility in South San Francisco allowing faster delivery, better quality assurance, and a larger staff. The company also expanded its research and development department. ATN’s 6015WP is a National Tactical Officer’s Association (NTOA)-approved night vision device that renders the display in black, white, and grey. These hues are much easier on the eye than standard night vision green.

Centurion Systems

Centurion Systems makes Yukon and Sellmark night vision and optics products. Its Multitask handheld monocular is a great solution for patrol officers at a price point that won’t make your admin folks blow their lattes through their noses when they get the invoice. The Multitask unit can also be mounted on head gear. It features automatic brightness control with user-friendly controls, an integrated (25mW) IR illuminator, and a weather-resistant housing.[PAGEBREAK]Digital Ally

Digital Ally offers the Thermal Ally imaging system. It's a small handheld unit that has five different color palettes, focus-free lens video recording and output capabilities, and operates on rechargeable batteries.

FLIR

What do you say about the big dog on the thermal imaging porch? FLIR (from the acronym Forward Looking Infrared) has been around since 1978 and makes all sorts of thermal systems for the military, law enforcement, and commercial markets. So if you need a thermal camera for your helicopter, command vehicle, or that M1 tank SWAT has hidden in the back of the armory, these guys are your solution. Fortunately for us patrol guys, they also make smaller stuff. FLIR's H-Series HandHeld Law Enforcement Thermal Imager includes several great features for cops such as onboard video storage with real-time clock, wireless streaming video transmission, over six hours of operation on a single charge, and more than 120 hours of standby battery life. An optional lens extender allows you to see a man from more than 2,800 feet.

ITT Exelis

If you have Gen 3 night vision equipment, chances are its light amplification elements were produced by ITT, regardless of who sold it to you or what name is on the side. The company makes the overwhelming majority of all Gen 3 tubes. Last year ITT split into three separate companies and ITT Exelis is the company that makes its night vision products. This year the company is debuting two potentially groundbreaking products: the iAware night vision system, which lets an operator see video from other sources while maintaining night vision surveillance; and the DGNVG, which combines a Gen 3 tube and thermal imaging micro-bolometer into the same monocular.

L-3 Warrior Systems

L-3 now manufactures just about every system you can put on a gun, in a soldier's hand, or on the transmission hump of your cruiser. Its CNVD-T is a lightweight, multi-platform thermal imager, providing moving man-sized target detection performance over 500 meters. The CNVD-T can be weapon mounted as a standalone sight or in combination with existing day optics. Its small size also increases its versatility and makes it great as a handheld imager.

Night Optics USA

Night Optics USA has been an innovator in the night vision industry for more than 18 years. The company’s NO/TS-640 is a rugged, lightweight, and powerful thermal weapon sight with a quick-release M1913 Picatinny mount. Made for military, law enforcement, and commercial use, the NO/TS-640 is a good mid-to-long-range sight as well as a surveillance tool. The NO/TS-640 has a 640x480 high-resolution display for crisp white hot or black hot images regardless of ambient conditions.

NIVISYS

The motto at NIVISYS is "Don't Fear The Dark." The company produces and distributes a full array of night vision and thermal devices, aiming lasers, and accessories for all of its products. The NIVISYS NSV-80 is a Gen 3 night vision device that clips on in front of an existing daylight optic. The great thing about it is the shooter doesn't need to make any adjustment to the sight. Point of aim and point of impact remain the same.

N-Vision Optics

N-Vision Optics has a customer base that includes the U.S. military as well as state, federal, and international law enforcement agencies. The company specializes in night vision equipment, thermal imaging devices, targeting/illumination systems, and custom optical solutions.

N-Vision Optics' Tactical Night Sight (TaNS) is a high-resolution clip-on night vision device that mounts on any Picatinny rail forward of an existing scope. It adds night vision capabilities to your existing daytime sight. The TaNS features a Gen 3 image intensifier tube, a fast f/0.9 catadioptric lens, and patented permanent boresight alignment technology.

US Night Vision

US Night Vision manufactures and assembles an exclusive line of products at its facility in Roseville, Calif. The company also distributes U.S.-manufactured products from ITT Exelis, FLIR, and L-3.

Dave Douglas retired from the San Diego Police Department as a sergeant and the department’s rangemaster. He has held positions in various law enforcement assignments, including patrol, investigations, bombs and arson, and training. He’s a long-time contributor to POLICE Magazine.

Related:

Night Vision vs. Thermal Imaging (video)

Thermal Imaging (photos)

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