Forward looking infrared (FLIR) cameras, typically used on military aircraft, use an imaging technology that senses infrared radiation.
The sensors installed in forward-looking infrared cameras—as well as those of other thermal imaging cameras—use detection of infrared radiation, typically emitted from a heat source, to create a "picture" assembled for video output. They can be used to help pilots and drivers steer their vehicles at night and in fog, or to detect warm objects against a cooler background. The wavelength of infrared that thermal imaging cameras detect differs significantly from that of night vision, which operates in the visible light and near-infrared ranges (0.4 to 1.0 μm).
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