The fact that the image in a night vision device always has a distinctive green hue is known not only to intelligence agency personnel but also to ordinary computer game enthusiasts. Why was this particular color chosen? Let’s try to understand!
Why green?
The green hue was not chosen randomly. Through numerous experiments, it was established that the details of a monochromatic image are best perceived by the human eye in green color. It turned out that we can distinguish many shades of green, making it easier for us to see the picture on the monitor and understand what is happening.
There is another reason. If the image were made white, the eyes would quickly tire from it, reducing perception accuracy. And this cannot be allowed. Night vision devices are used during military operations and other important events where extra risk should be avoided.
Night vision devices of zero and first generations
The first night vision devices appeared quite a long time ago, back in the 1930s, almost a century ago. They were invented by German scientists and were installed on optical sights. Moreover, they could weigh several tens of kilograms (including the battery).
The device emitted an infrared beam, which reflected off objects and hit a special lens. Thanks to this, it became possible to “see” in the dark. Such devices were not popular not only because of their considerable weight. The enemy could detect the infrared beam, putting the “user” of the device at risk of being destroyed.
First-generation devices used optical converters that amplified the incoming signal several tens of times. This made the image distinguishable. The devices picked up the faint reflected light, for example, that emanating from stars or the Moon, and illuminated dark objects with it. That’s why such devices were called “starlight scopes.”
Second and third-generation devices
The most significant improvements occurred in second-generation devices. Their resolution increased, affecting the image quality. Moreover, objects could be seen even if the sky was cloudy, meaning there were no stars or the Moon. Such impressive achievements were made possible by using a special microchannel plate.
Third-generation devices are considered the most advanced. They are used by modern American military personnel during their operations. These devices are almost indistinguishable from second-generation ones. However, more advanced components are used in them, making the image practically perfect.
Moreover, the “picture” will be clear and easily distinguishable even in complete darkness. Fourth-generation devices additionally use amplifiers, which allow excellent visibility under any lighting conditions. In other words, even if there are no photons in the room, the image will still be formed and perfectly discernible to the human eye.
Night vision devices – an invention that has influenced the course of human history. Thanks to them, soldiers gained the ability to see in the dark, carrying out previously unthinkable military operations. If the first devices weighed several tens of kilograms, modern models can be used even by a child! And the green color for the image was chosen for a simple reason: evolutionarily, the human eye distinguishes more shades of this tone, so the brain perceives the image better.