Most people like to think about spy movies and war movies, when one considers night-vision goggles, but my love affair with this technology goes back to kreskówkowo large device NVD (night vision devices) used young Tim Murphy in Jurassic Park. Made the coolest toy in a series of vertically integrated products released by Universal but never got a pair from my parents.
Looking back, the toys never wykonałyby tasks that you saw in the film. It was just a giant pair of green glasses, which contributed to the fact that the world around you look a bit like images from a pair of night vision goggles. Why green? Well, we’ll get there. But first, a lesson in light.
People see only part of the available light along what we call a Ghost, is visible. Above this the spectrum is ultraviolet (the substance that gives you a sunburn), and below that is the infrared light (light used remote). NVD respond to infrared light and visible light, so that they can collect light, whose wavelength is too big to our eyes can detect.
When light passes through the lens or lenses on a pair of night vision goggles, meets a number of plates, which increase its power. The first one is called fotokatodą, which is negatively charged disk, which throws the electron further in the tube, in correspondence with each fotonem of light that had struck him.
The next element is called mikrokanaliką or MCP. When electrons pass through MCP fotokatody, electric pulses with a voltage of 5000 volts accelerate them through microscopic channels in the glass. In transit through these channels MCP emits thousands of electrons, which again meet the position and intensity of source photons. This is due to a phenomenon called secondary emission gradually.
At the end of these again multiplied electrons pass through the screen covered luminoforami. The energy of the electrons excites the phosphors, in which the electrons release photon particles when they descend from the state of wzbudzonego. These glowing photons are what catches the green color image night vision camera from which the light passes through the lens frame of a spectacle for the eyes.
In short, these glasses use all the available light from the band via the IR spectrum of visible light, it turns the photons into electrons, exponentially multiply the electrons and restore all these new electrons back to photons, which then focus on the brightness. image in night vision mode.
Two eyes are better than one
The choice of googles night vision from our list will probably lead to the planned for them to use. Although there are many striking similarities from set to set, you should notice at least one or two major differences between them.
For a start the tube matrix or lamps. Some couples from our list of use a single tube that divides the image between two points. The effect is a bit more similar to the view through the telescope of the pirates, than, say, binoculars.
For this last effect need stereo glasses with two lamps unnoticed processors to each eye. This type of glasses provides a much better depth perception, but also requires twice as much equipment for medical imaging compared to the more simple cousin. This means that, as a rule, much more expensive.
Speaking of spyglasses and lornetce, it can be expected that these devices will also increase the image observed. While some of the points in our list can boast some degree of increase, they are not always included, and not all they fit. Imagine a group of Marines in close, dark fight, the enemy only five or ten feet further. An 8-fold increase (relative to the standard improvement of conventional binoculars) the soldiers in question will never see clearly the enemy.
This is an extreme example, of course, but it shows that each increase is built into your chosen glasses should be used for most of your goals, because otherwise, can become a burden.
Let Your Little Light Shine
The first night vision goggles being used in the battlefields of the II II and the Korean war. They used technology called active infrared, which sends a beam of infrared light in the open air for the environment, as well as the flashlight’s beam. In addition to weaker power and clarity compared to modern googles, anyone who has the technology noktowizyjną, can easily see the beam emitted through your points and determine the position.
The first night vision goggles to avoid the active infrared system was based largely on the light rzucanym the stars and the moon to collect data, but on a moonless or cloudy night, this technology has proved very effective.
Tile mikrokanalikowa was another addition to the technology, goggle and all of a sudden these images were clearer and brighter than before, as the number of available electrons has increased dramatically. The army then improved the design and makeup fotokatody at the top of the pipe that marked the beginning of a much cleaner and more accurate transfer of the electron.
The technology currently used by the military are available worldwide, although there are prohibitions of the export of certain brands and styles, because the US is trying to stop some of his remaining cards, technology the nightstand next vests.