Infrared cameras work by detecting the infrared radiation emitted by objects in their field of view. All objects emit infrared radiation as a result of their temperature, with hotter objects emitting more radiation than cooler objects.
Infrared cameras use a special sensor called a focal plane array (FPA) to detect this emitted radiation. The FPA is made up of thousands of tiny infrared detectors, each of which measures the infrared radiation at a specific point in the camera's field of view.
When infrared radiation strikes the FPA, it causes each detector to generate an electrical signal. These signals are then processed by the camera's electronics to create a thermal image of the scene being observed. The intensity of the infrared radiation at each point in the image corresponds to the temperature of the object at that point.
Infrared cameras are often equipped with color palettes that map different temperature ranges to different colors, making it easier for users to interpret the thermal images produced by the camera. These images can be used for a variety of applications, including night vision, security monitoring, medical imaging, and building inspections.