Night vision technology today is a familiar and common thing for us. She has become a part of popular culture and even an ordinary housewife. Today, seeing a green glow on the screen, we immediately realize that the film's heroes participate in a night operation.
We all remember with warmth how we played video games in childhood, eliminating terrorists in the night mode. From the legendary Delta Force to Call of Duty and hundreds of other awesome games, we've gotten into the role and enjoyed amazing military technology.
Today, thanks to modern advances in science, we can not only feel in reality the impressions that games teased us within childhood but also become the owner of such an amazing device. The increased opportunities, which today are limited only by our bank account and imagination, still do not answer some questions.
For example, be honest, have you ever wondered why the color of night vision is green? Not red, not blue, not purple, after all? What is this - a conspiracy of the Freemasons, the intrigues of a secret government, or a symbolic attribute? Let's figure this out.
Let's start over. Night vision technology has various uses in both the civilian and military sectors, as it can be used for security, surveillance, and numerous outdoor activities. Nightvision was first developed for military use in the 1940s and was readily utilized during Military conflicts in the Korean and Vietnam wars. These devices were quite large and cumbersome but were cutting edge technology that empowered militaries the first advantage of seeing in the dark. Some of the first images that come to mind when hearing the topic of NightVision are the visual field's green color. This article will provide some backdrop on the development of night vision and the reason for the green field of view.
Invention and progression of night vision
The inability to conduct hostilities at nightfall and the difficulty of observing at night created problems for conducting any active hostilities throughout civilization's history. This not only made it impossible to attack operations in the dark but endangered the troops. A sabotage group in the rear becomes a thousand times more dangerous when you do not see it.
It is only logical that the best minds associated with the military industry worked to expand visual identification possibilities. And in the 20th century, the technological revolution began to bear fruit.
The first practical night vision devices were developed in Germany in the mid-1930s and used by German tanks and infantry during World War II. U.S. Military scientists had simultaneously developed their own night vision devices that first saw use during WWII and the Korean War.
These were devices that can hardly be called devices in their modern sense. Huge, bulky, impractical, and very fragile, they were not so much useful as the very fact of their existence inspired them. Namely, this equipment became the starting point in developing the NV industry and received the name “Generation 0”.
At the heart of the generation was the Holst Glass, the first engineering prototype developed at the Dutch company Philips by Holst and his group in the 1930s. During World War II, German troops began to implement equipment into their tactical arsenal actively.
But even before Holst's experience, work on creating such devices was actively carried out by all developed countries. And because of this, the Hungarian scientist Kalman Tihanyi deserves a special mention.
Working in Great Britain in 1929, he invented the infrared-sensitive electronic television camera, which was intended for air defense. And, given how much the island suffered from the Germans' brutal air raids, any invention that helped to minimize losses and damage from bombing was a real scientific and civilian breakthrough.
The characteristic result of even low-performance night vision equipment is a tremendous advantage on the battlefield. For example, the Nazis defeated the Communist troops in battles in Lake Balaton, Hungary. The losses were enormous, and the Germans' night strikes' accuracy was so impeccable that the Russians threw all their strength into thinking over a strategy of protection from the enemy's absolute sight.
The communists did not come up with anything better than flashing the German army's positions with anti-aircraft searchlights, but, honestly, even such a primitive solution turned into a very effective method. True, the backward Soviet army, supported by the allies, could not technologically withstand the Axis countries, making the communists feel very defective. Therefore, to this day, in Russian historical literature, the use of searchlights is associated with a psychological attack on the Nazisб but not the trying to attempt to resist modern technologies not with the help of science, but with the help of improvised means.
These “Generation 0” devices used active infrared to brighten up a scene. Soldiers carried an IR illuminator to shoot a near-infrared light beam that then reflected off objects and bounced back to the lens of their scope and created a visible image of what they were looking at. The illuminators used by the German Nachtjägers, or "night hunters," were about the size of dinner plates and required a large power supply carried on the soldier’s back.
Sounds incredibly impractical and difficult. But, in those days, it was not just a breakthrough. This was a real and unique advantage on the battlefield.
It must be understood that such a complex technology cannot be compared with other branches of military affairs. For example, the operation and design principles of pistols and revolvers have not changed significantly since the late nineteenth century. That is, the beautiful and shiny Desert Eagle or the compact and lightweight Glock that you can buy today is no different from the models that our ancestors used 150 years ago. With night vision, things are very different, for obvious reasons. The principle of their work, of course, has not changed. In fact, it copies the mechanisms of vision of domestic cats. But it took time and scientific advances to make the elements compact and cheap.
The technology made huge leaps in the following decades. By the time the U.S. entered the Vietnam War, many troops were outfitted with passive "starlight scopes" that used image-intensifying tubes to amplify available ambient light (usually from the moon and stars, hence the name) and produce an electronic image of a dark area.
To understand how far we have gone, we can mention that you can purchase a kit that will allow you and your children to build a primitive night vision device in the store. It will be functional and working, and in its characteristics, it will not be much inferior to the first samples of the zero generation.
Technology behind night vision, why is it green?
Nevertheless, let's return to our main question, "why is the image color of the night vision device green?" And, if you think it's because green, according to popular theory, is preferred by geniuses, you're mistaken.
There are main technologies that are used in the development of night vision. The first type of technology is active illumination technology that couples imaging intensification with a source of illumination in the near-infrared band. The second technology, image intensification, holds the answer as to why night vision is green. Image intensification technology provides us with that famous bright green light in night vision goggles.
If this sounds complicated and confusing, then it’s time to delve into the essence of the process of visualizing objects that are hidden by the darkness of the night. And we are talking about darkness, as your device will become useless if you use it in fog, blizzard, or even heavy rain. Science has other solutions for these conditions.
But what makes the symbiosis of sophisticated equipment in a night vision device? It maximizes the amount of light received from natural sources such as starlight or moonlight and “amplifies” it in night vision devices to get a clear image as possible. Unfortunately, this means that night vision goggles with this technology can’t work in complete darkness, since it actually doesn’t amplify the light. Rather it illuminates it up to a level at which the human eye can detect it. When photons hit the lens at the front of night vision goggles, they are still carrying the light of all colors. But when they are turned into electrons, they lose that information, and incoming color light is turned into black and white. But why is night vision green then?
The main reason is that the image intensification screen inside the device is made of phosphor. This substance is used because of its luminance effect, and when struck by electrons that don’t carry color information, it glows bright green. As the electrons pass through the tube, they flow through a microchannel plate, a disc with millions of microchannels. Striking these microchannels bursts of voltage causes the motion to increase rapidly, forming dense clouds of electrons that intensify the original image. These same electrons then strike a screen coated w / phosphor at the end of the tube. The energy from these electrons creates the greenish image on the screen inside the device. Green phosphor is used because the human eye is most sensitive to the green color pallet and distinguishes more shades of green than any other color.
Everything is so boring and prosaic ... Of course, we would like the answer to this question to be more romantic and mysterious, but like most answers in our life, it is logical and even boring.
The utilitarian meaning of green light is not limited to this. When decoding an image from the black and white spectrum, the flow of electrons is no longer as intense, which means that the device spends less energy to render the image, which leads to an increase in the operating time of your device. And saving energy is sometimes a priority, given the conditions in which the device is usually used and the tasks performed with its help.
Besides, when we talk about the range of perception of green shades in the human eye, we cannot underestimate this factor. Even for the average human eye, this is a huge advantage. And if you work with equipment on an ongoing basis, then over time, you yourself will be surprised how many details you will discover in the mysterious green glow. The human body is an amazing tool, and it is capable of constant surprises. For example, people who constantly work with color, for example, artists, see up to 400 variants of only green.
Also, this color scheme is similar to the effect of a children's night light. In addition to the calm range and the unobtrusive glow for the brain, the eyes will get tired of it much more slowly. This means that you will maintain a reaction and full functionality for a longer time.
We do not advise you to discard the idea of buying a device with a black and white display gamut. Based on the facts above, our pick is a classic. It all depends on the first rule of buying a night vision device - understand the purpose for which you need a device. The chances are good that contrast is more important to you. It is better displayed in a monochrome mode more familiar to the human eye. Therefore, never deprive yourself of choice.
Night vision has made significant advancements in size, clarity, visibility, and price over the last 70 yrs. With continual advancements in technology, there are several breakthroughs in development, and it will be exciting to see where the night vision industry goes.
But, in any case, the main direction for us is clear. Reducing and lightening devices, reducing the cost of its components, and, as a result, increasing the availability of night vision devices. This is great news, as the applications of the devices are growing with their development. And, today they are not limited to military purposes and hunting.
Today everyone can feel like Sam Fisher and plunge into childhood memories created by games and action movies, feeling a mysterious green glow that leaves no chance for the darkness to hide something.