How Does Night Vision Work?



Night-vision seems like a pretty cool idea right. I mean you see it all the time in movies. Some secret agent type straps on a pair of goggles sneaks into a look jury is super villain compound and mows down enemies under the cover of darkness or the Predator. Stocks Arnold Schwarzenegger killing his platoon. One by one by one and as you're watching all this you may occasionally ask yourself. Hey do those goofy looking goggles really work? Well the answer is yes absolutely with a good night vision device or Envy D. You can see a person standing over two hundred yards or one hundred and eighty three meters away on a moonlit cloudy night and whether we're talking goggles scopes or cameras. Most of these devices rely on one or two types of night vision image enhancement. That's the green looking one and thermal imaging. Which is the bluish-gray Stuff. They both produce results but work in different ways. Thermal imaging captures the upper portion of the infrared light spectrum objects amid the as heat rather than reflecting it as light hotter objects such as the bodies of secret agents emit more of this light than cooler objects like buildings trees. Or you know dead bodies. And that's what you're seeing when you use thermal imaging essentially a measure of temperature from negative four degrees Fahrenheit two three thousand six hundred degrees Fahrenheit the magic or well you know. The science starts at the Lens which focuses the infrared light emitted by the objects in view and uses a phased array of infrared detector to create a temperature pattern called a thermographic which is translated first into electric impulses and then into data for the display where it appears as various colors. Depending on the intensity of the infrared. Then there's image enhancement. This collects tiny amounts of light including the lower portion of the infrared light spectrum and amplifies zip devices using this approach rely on an image intensified tube to collect amplify light both the infrared kind and the visible stuff image enhancers us a photo cathode to convert photons into electrons and high voltage to amplify those electrons in a micro channel plate or an MCP before they hit a screen. That's coated with foster's here's the crazy part. These electrons maintain their position. In relation to the micro channel. They passed through which provides a perfect image. Since the electrons stay in the same alignment as the original photons. When they hit the screen they're energy sites. The Fos- fers releasing photons. Those phosphorus create the green image. You see when you look through a night vision scope

Coming up next