Night vision facts for kids

Night vision is the amazing ability to see in very low light, almost like it's daytime! Some animals, like cats, have natural night vision. This means their eyes are built to see well even when it's nearly dark. Humans, however, don't have great natural night vision. If there isn't enough light for us to see clearly, we might need special tools called night vision devices, like night vision goggles, to help us out.

Night vision devices usually work in two main ways:

This image shows how night vision can make a dark scene much brighter using amplified light.

This picture uses infrared technology to show heat, like the warmth from a floor heating system.

How Night Vision Works

Night vision devices help us see in the dark by either making tiny bits of light much brighter or by seeing heat that our eyes can't normally detect.

Light Amplification

One type of night vision works by amplifying light. This means it takes the very small amount of visible light that's already there and makes it much brighter. It's like turning up the volume on a quiet sound until you can hear it clearly. This type of night vision works well outdoors, where there's usually a little bit of starlight or moonlight. However, it won't work in a place that's completely dark, like inside a cave with no light at all.

Infrared Vision

The other main type of night vision uses infrared light. This is a part of the light spectrum that our eyes can't see. Infrared vision actually "sees" heat energy. Everything that is warm, like animals, people, or even vehicles, gives off heat. Infrared cameras can detect this heat, making warm objects stand out clearly, even in total darkness. This means you can see things that are warm even when it's completely black.

Images for kids

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  Two American soldiers during the 2003 Iraq War, seen through an image intensifier.

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  A USMC M3 Sniperscope on an M1 Carbine. This early infrared night vision gear was used during the Korean War and needed a big battery carried in a backpack.

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  An M60 tank with an infrared searchlight on its cannon.

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  Binocular night vision goggles on a flight helmet. The green color on the lenses is from light filters, not a glow.

See also

In Spanish: Visión nocturna para niños