thermal monocular

A thermographic weapon sight, thermal imagery scope or thermal weapon sight is a sighting device combining a compact thermographic camera and an aiming reticle. They can be mounted on a variety of small arms as well as some heavier weapons.
As with regular ultraviolet sensors, thermal weapon sights can operate in total darkness. Unlike optical scopes, thermal sights don't rely on visible light, allowing them to function in complete darkness.The thermal scope can be quite useful in places with snow as the extreme difference in temperatures between the snow and any source of heat (such as a human) creates a high visual contrast between the two. This makes it easy to locate any source of heat against its low-temperature background.

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