Night Vision: Eliminating Confusion
By Chief Tom Dugan (ret.)
For decades, night vision equipment has given law enforcement (and military) personnel an undisputed advantage in preventing and responding to crime and protecting citizens in low-light and no-light situations. Night vision has helped them perform their jobs more effectively and safely. While there is no question that the technology is a valuable and potentially life-saving asset that every officer should have, there are several things to know before selecting the night vision equipment that will maximize your agency’s performance and optimize officer safety.
Throughout the years, there have been significant changes in night vision technology. However, there remain two primary types: image intensification and infrared (thermal) imaging. It is important to test both types and know the difference between them, as well as understand the benefits and drawbacks of emerging technologies.
Image intensification, or light amplification, converts a small amount of light energy (moonlight or starlight, for instance) into electrons. Electrons then pass through a thin disk – containing more than 10 million microscopic holes – that multiplies the electrons, converts them to photons and ultimately yields a clear image in seemingly total darkness. This type of night vision technology is categorized by “generation.”
The earliest form of light intensification technology was known as Generation (Gen) 0 and depended on external light to increase the available light energy. This technology has become obsolete. Gen 1, its successor, while improved, is outdated technology that is used primarily in imported night vision products. With the advent of Gen 2 came the development of a microchannel plate, which multiplies the number of electrons by the thousands. Thus, Gen 2 lacks the distortion of Gen 0 and Gen 1, producing a clearer image.
Gen 3, however, is the best and most sophisticated night vision technology in the world. In addition to providing the highest resolution and clearest night vision images available, Gen 3 equipment also can perform effectively for several years, longer than earlier technologies. With ITT Night Vision’s Gen 3 PinnacleTM technology, law enforcement officers can discern critical details such as whether a suspect is holding a weapon or simply has a phone in hand, and whether the person has any notable facial characteristics such as a mustache or other unique features.
There are two essential things buyers must know when it comes to image intensifying night vision technology. Gen 3 is the most advanced technology available. Using Gen 1 or Gen 2 is not a suitable, low-cost replacement for Gen 3, but rather is comparable to using computers that were manufactured more than a decade ago. Equally important is knowing which night vision manufacturers produce Gen 3 technology. An easy way to avoid confusion is to remember that two U.S. manufacturers produce Gen 3 technology, one of which is ITT Night Vision, the leading manufacturer of night vision equipment for U.S. and allied military forces, as well local, state and federal law enforcement officers. Northrop Grumman is the only other manufacturer of Gen 3 technology.
Thermal imaging relies on a lens that focuses infrared light emitted by all objects in view. A phased array of infrared detector elements scans the focused light, quickly obtaining objects’ temperature information and creating a pattern known as a thermogram. Thermograms are then translated into electric impulses that are sent to a signal-processing unit that then creates an image that appears in various colors. (The colors displayed in the image correspond with the amount of heat being radiated by the object in view.)
Thermal imaging is a useful tool for detecting images that might be obstructed by objects or substances such as smoke or fog. However, one significant disadvantage is that thermal imaging does not provide detailed images. With this technology, there is no facial recognition. In addition, smaller objects such as weapons – unless the suspect is carrying a gun that has been fired recently – cannot be easily detected.
A lesser known and unproven – but highly marketed – night vision technology relies on a charged-coupled device (CCD) chip and digital signal processor to transform ambient light that is invisible to the naked eye into an image. Some companies claim their products have “super” abilities that enable them to zoom in on objects to provide greater details of the image from longer distances. Unfortunately, these products also require significantly higher amounts of natural or artificial light to produce such results, limiting their usefulness in low-light and no-light situations. Therefore, it is critical that products that claim to have this sort of ability be tested in all light situations.
What to Know Before Purchasing Night Vision Equipment
As we all know, it is impossible to assign a value or dollar amount to human life. So, when purchasing night vision equipment that could mean the difference between saving a human life – either yours or one you are sworn to protect – or failing to do so, can you afford to go with inferior technology?
To avoid this potential pitfall, take into account the following checklist of things to know before purchasing night vision equipment.
Chief Tom Dugan is retired from the Glen Ridge Police Department in Glen Ridge, N.J., and currently serves as Law Enforcement Projects Coordinator for ITT Night Vision in Roanoke, Va. For more information about night vision, contact Chief Dugan at Tom.Dugan@itt.com or visit ITT’s Web site.
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