Mention night vision devices and what usually jumps to mind is an action packed military movie. In reality, night vision technology has filtered down to where it is accessible for civilians as well. Improvements since its development with the so-called Generation 0 during World War II have been immense. There are now a wide variety of interesting gadgets available to the public at many price points. You don’t have to be a professional soldier or a survivalist to appreciate how useful and even fun it can be to have a whole new world of nighttime visibility available. If you’ve ever wondered what it’s like for a stealthy nocturnal animal to be able to navigate without a flashlight, a night vision device will give you a pretty good idea of what it’s like not to be restricted by the limited range of human eyesight.
Night vision devices generally fall into two categories, those that “see” by 
using image inhancement to capture low level light rays that are below the scope of normal human vision and those that use thermal imaging to detect heat emitted by higher frequency infrared waves in the environment and turn it into visible images. Thermal imaging (more recent generation) devices can generally detect differences in temperature of less than one half degree fahrenheit, from up to approximately -4 degrees to 3,000 degrees. These are the devices that enable law enforcement personnel to, among other things, detect minute disruptions in ground temperatures that indicate soil has been moved and thus locate hidden graves and illegal caches. Surface disturbances allow air to penetrate, changing the temperature and allowing thermal imaging night vision devices to pick up recent changes that may be invisible to the nake eye.
The ability for humans to see beyond their normal visual range opens up a whole new hidden world. Many security systems now come with night vision technology, complete with cameras that can monitor an area and film would-be intruders in the dead of night. Night vision scopes allow campers and hunters to watch the environment without causing a disturbance and even find that dropped set of car keys at the campsite without being detected. Binocular type can headsets allow the nature lover to observe noturnal wildlife without scaring them into hiding. A decent and reasonably priced night vision device will be able to display a large animal (or human) form from at least 200 yards in the dead of night with no moonlight. The same thermal imaging technology that aids law enforcement in detecting those recent digging sites can even allow detection of recently repaired masonry walls, something that might be of interest to perspective home buyers.
The potential uses of night vision devices are probably infinite. Whether you want to play party pranks on unwitting houseguests, play detective in your neighborhood or simply be able to observe wildlife undetected, night vision devices can affordably enhance your world view and allow you to have some fun as well. With recent generation night vision technology, you are no longer limited to what you can see with a naked eye in the beam of a flashlight. Whether you are just a technology hobbyist who likes to impress their friends with the latest gadget or whether you are seriously looking for an enhanced feeling of safety and security, night vision technology is your answer. The dark need no longer hold any mystery.
The Way Night Vision Works
By Shawn Davis
Most people are familiar with the concept of night vision. After all, it is seen in countless action and spy movies. However, the truth is that night vision is more than a fantastical concept; it is reality. And with goggles, night scopes, binoculars and monoculars, it is possible to see on a moonless, cloudless night. In fact, the technology is so advanced that you can see a person standing more than 200 yards away. That’s twice the length of a football field! The remarkable feat of human sight at night is accomplished one of two ways: image enhancement or thermal imaging.
Image enhancement is a night vision technique that collects tiny amounts of light that may not be perceptible to the human eye. These are the smallest glimmers of light, sometimes even on the lower end of the infrared spectrum, that are discovered by the device in use. The points of light are than amplified by the device to a point that allows the object or person to be seen easily.
The other way night vision works is by thermal imaging. This is technology that works exclusively in the upper portion of infrared light. Rather than gathering reflected light, this is heat that is given off by objects or people. This is known as thermal infrared, and it occupies the largest amount of space as part of the infrared spectrum (which is at the lower end of the light spectrum, below what is detectible by the human eye). This means that there is a great deal of wavelengths that can be detected by the proper devices. Because thermal imaging works by putting the heat coming from objects in visible form, it is to be expected that some objects will appear clearer than others. Humans, for example, emit more heat than a tree, and so a tree will not be as clear.
Night vision products make excellent additions to any surveillance collection, and they can be very helpful in locating objects or people in dark places. You will pay in a price range from under $300 to more than $15,000, depending on features, accuracy, and purpose of the accessories you choose to aid your night vision.
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