How night vision goggles achieve night vision

There is a small amount of natural light in the dark environment at night, such as moonlight, starlight, atmospheric glow, etc.,night vision scope， which are collectively referred to as night sky light. Because they are very faint compared to sunlight, they are also called noctilucent.

The human retina is not very sensitive to light and cannot be adequately "exposed" in low light conditions. This is also one of the reasons why people cannot observe normally in a dark environment. In the dark environment at night, in addition to the existence of low light, there is a lot of infrared light.

All objects in the world emit infrared light all the time, so whether it is day or night, space is filled with infrared light. But infrared rays, no matter how strong or weak, cannot be seen by humans.

The night vision device uses both weak light and infrared conditions to convert the invisible light (weak light or infrared light) signal from the target into an electrical signal, and then amplify the electrical signal to convert the electrical signal into the human eye. visible light signal. Photoelectric conversion is a common way for all night vision devices to achieve night vision.

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