The thermogram is converted into electrical impulses that are sent to a signal processing unit, which produces an image for display. This image appears in various colors depending on the heat of the element being scanned; what some refer to as “real night vision” is the result, with hotter images like bodies emitting a greater amount of distinguishing light.
Similar to the human eye, regular visible cameras rely on the reflected light that is blocked by certain visual impediments. Not only can thermal imaging cameras see in complete darkness, they also allow users to clearly see-through obscurants. The same can also be said for surveillance issues involving natural scene camouflage.
Who needs thermal cameras?
If you need round-the-clock advance warning on a remote site that people are approaching your premises, then thermal imaging makes a great deal of sense. Bodies and engines give off more heat, so a thermal camera can detect long before a standard camera could.